2 # (C) Copyright 2000 - 2013
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # SPDX-License-Identifier: GPL-2.0+
11 This directory contains the source code for U-Boot, a boot loader for
12 Embedded boards based on PowerPC, ARM, MIPS and several other
13 processors, which can be installed in a boot ROM and used to
14 initialize and test the hardware or to download and run application
17 The development of U-Boot is closely related to Linux: some parts of
18 the source code originate in the Linux source tree, we have some
19 header files in common, and special provision has been made to
20 support booting of Linux images.
22 Some attention has been paid to make this software easily
23 configurable and extendable. For instance, all monitor commands are
24 implemented with the same call interface, so that it's very easy to
25 add new commands. Also, instead of permanently adding rarely used
26 code (for instance hardware test utilities) to the monitor, you can
27 load and run it dynamically.
33 In general, all boards for which a configuration option exists in the
34 Makefile have been tested to some extent and can be considered
35 "working". In fact, many of them are used in production systems.
37 In case of problems see the CHANGELOG file to find out who contributed
38 the specific port. In addition, there are various MAINTAINERS files
39 scattered throughout the U-Boot source identifying the people or
40 companies responsible for various boards and subsystems.
42 Note: As of August, 2010, there is no longer a CHANGELOG file in the
43 actual U-Boot source tree; however, it can be created dynamically
44 from the Git log using:
52 In case you have questions about, problems with or contributions for
53 U-Boot, you should send a message to the U-Boot mailing list at
54 <u-boot@lists.denx.de>. There is also an archive of previous traffic
55 on the mailing list - please search the archive before asking FAQ's.
56 Please see http://lists.denx.de/pipermail/u-boot and
57 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
60 Where to get source code:
61 =========================
63 The U-Boot source code is maintained in the Git repository at
64 git://www.denx.de/git/u-boot.git ; you can browse it online at
65 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
67 The "snapshot" links on this page allow you to download tarballs of
68 any version you might be interested in. Official releases are also
69 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
72 Pre-built (and tested) images are available from
73 ftp://ftp.denx.de/pub/u-boot/images/
79 - start from 8xxrom sources
80 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
82 - make it easier to add custom boards
83 - make it possible to add other [PowerPC] CPUs
84 - extend functions, especially:
85 * Provide extended interface to Linux boot loader
88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
89 - create ARMBoot project (http://sourceforge.net/projects/armboot)
90 - add other CPU families (starting with ARM)
91 - create U-Boot project (http://sourceforge.net/projects/u-boot)
92 - current project page: see http://www.denx.de/wiki/U-Boot
98 The "official" name of this project is "Das U-Boot". The spelling
99 "U-Boot" shall be used in all written text (documentation, comments
100 in source files etc.). Example:
102 This is the README file for the U-Boot project.
104 File names etc. shall be based on the string "u-boot". Examples:
106 include/asm-ppc/u-boot.h
108 #include <asm/u-boot.h>
110 Variable names, preprocessor constants etc. shall be either based on
111 the string "u_boot" or on "U_BOOT". Example:
113 U_BOOT_VERSION u_boot_logo
114 IH_OS_U_BOOT u_boot_hush_start
120 Starting with the release in October 2008, the names of the releases
121 were changed from numerical release numbers without deeper meaning
122 into a time stamp based numbering. Regular releases are identified by
123 names consisting of the calendar year and month of the release date.
124 Additional fields (if present) indicate release candidates or bug fix
125 releases in "stable" maintenance trees.
128 U-Boot v2009.11 - Release November 2009
129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
130 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
136 /arch Architecture specific files
137 /arc Files generic to ARC architecture
138 /arm Files generic to ARM architecture
139 /avr32 Files generic to AVR32 architecture
140 /blackfin Files generic to Analog Devices Blackfin architecture
141 /m68k Files generic to m68k architecture
142 /microblaze Files generic to microblaze architecture
143 /mips Files generic to MIPS architecture
144 /nds32 Files generic to NDS32 architecture
145 /nios2 Files generic to Altera NIOS2 architecture
146 /openrisc Files generic to OpenRISC architecture
147 /powerpc Files generic to PowerPC architecture
148 /sandbox Files generic to HW-independent "sandbox"
149 /sh Files generic to SH architecture
150 /sparc Files generic to SPARC architecture
151 /x86 Files generic to x86 architecture
152 /api Machine/arch independent API for external apps
153 /board Board dependent files
154 /common Misc architecture independent functions
155 /configs Board default configuration files
156 /disk Code for disk drive partition handling
157 /doc Documentation (don't expect too much)
158 /drivers Commonly used device drivers
159 /dts Contains Makefile for building internal U-Boot fdt.
160 /examples Example code for standalone applications, etc.
161 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
162 /include Header Files
163 /lib Library routines generic to all architectures
164 /Licenses Various license files
166 /post Power On Self Test
167 /scripts Various build scripts and Makefiles
168 /test Various unit test files
169 /tools Tools to build S-Record or U-Boot images, etc.
171 Software Configuration:
172 =======================
174 Configuration is usually done using C preprocessor defines; the
175 rationale behind that is to avoid dead code whenever possible.
177 There are two classes of configuration variables:
179 * Configuration _OPTIONS_:
180 These are selectable by the user and have names beginning with
183 * Configuration _SETTINGS_:
184 These depend on the hardware etc. and should not be meddled with if
185 you don't know what you're doing; they have names beginning with
188 Previously, all configuration was done by hand, which involved creating
189 symbolic links and editing configuration files manually. More recently,
190 U-Boot has added the Kbuild infrastructure used by the Linux kernel,
191 allowing you to use the "make menuconfig" command to configure your
195 Selection of Processor Architecture and Board Type:
196 ---------------------------------------------------
198 For all supported boards there are ready-to-use default
199 configurations available; just type "make <board_name>_defconfig".
201 Example: For a TQM823L module type:
204 make TQM823L_defconfig
206 Note: If you're looking for the default configuration file for a board
207 you're sure used to be there but is now missing, check the file
208 doc/README.scrapyard for a list of no longer supported boards.
213 U-Boot can be built natively to run on a Linux host using the 'sandbox'
214 board. This allows feature development which is not board- or architecture-
215 specific to be undertaken on a native platform. The sandbox is also used to
216 run some of U-Boot's tests.
218 See board/sandbox/README.sandbox for more details.
221 Board Initialisation Flow:
222 --------------------------
224 This is the intended start-up flow for boards. This should apply for both
225 SPL and U-Boot proper (i.e. they both follow the same rules).
227 Note: "SPL" stands for "Secondary Program Loader," which is explained in
228 more detail later in this file.
230 At present, SPL mostly uses a separate code path, but the function names
231 and roles of each function are the same. Some boards or architectures
232 may not conform to this. At least most ARM boards which use
233 CONFIG_SPL_FRAMEWORK conform to this.
235 Execution typically starts with an architecture-specific (and possibly
236 CPU-specific) start.S file, such as:
238 - arch/arm/cpu/armv7/start.S
239 - arch/powerpc/cpu/mpc83xx/start.S
240 - arch/mips/cpu/start.S
242 and so on. From there, three functions are called; the purpose and
243 limitations of each of these functions are described below.
246 - purpose: essential init to permit execution to reach board_init_f()
247 - no global_data or BSS
248 - there is no stack (ARMv7 may have one but it will soon be removed)
249 - must not set up SDRAM or use console
250 - must only do the bare minimum to allow execution to continue to
252 - this is almost never needed
253 - return normally from this function
256 - purpose: set up the machine ready for running board_init_r():
257 i.e. SDRAM and serial UART
258 - global_data is available
260 - BSS is not available, so you cannot use global/static variables,
261 only stack variables and global_data
263 Non-SPL-specific notes:
264 - dram_init() is called to set up DRAM. If already done in SPL this
268 - you can override the entire board_init_f() function with your own
270 - preloader_console_init() can be called here in extremis
271 - should set up SDRAM, and anything needed to make the UART work
272 - these is no need to clear BSS, it will be done by crt0.S
273 - must return normally from this function (don't call board_init_r()
276 Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
277 this point the stack and global_data are relocated to below
278 CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
282 - purpose: main execution, common code
283 - global_data is available
285 - BSS is available, all static/global variables can be used
286 - execution eventually continues to main_loop()
288 Non-SPL-specific notes:
289 - U-Boot is relocated to the top of memory and is now running from
293 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
294 CONFIG_SPL_STACK_R_ADDR points into SDRAM
295 - preloader_console_init() can be called here - typically this is
296 done by defining CONFIG_SPL_BOARD_INIT and then supplying a
297 spl_board_init() function containing this call
298 - loads U-Boot or (in falcon mode) Linux
302 Configuration Options:
303 ----------------------
305 Configuration depends on the combination of board and CPU type; all
306 such information is kept in a configuration file
307 "include/configs/<board_name>.h".
309 Example: For a TQM823L module, all configuration settings are in
310 "include/configs/TQM823L.h".
313 Many of the options are named exactly as the corresponding Linux
314 kernel configuration options. The intention is to make it easier to
315 build a config tool - later.
318 The following options need to be configured:
320 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
322 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
324 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
325 Define exactly one, e.g. CONFIG_ATSTK1002
327 - CPU Module Type: (if CONFIG_COGENT is defined)
328 Define exactly one of
330 --- FIXME --- not tested yet:
331 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
332 CONFIG_CMA287_23, CONFIG_CMA287_50
334 - Motherboard Type: (if CONFIG_COGENT is defined)
335 Define exactly one of
336 CONFIG_CMA101, CONFIG_CMA102
338 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
339 Define one or more of
342 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
343 Define one or more of
344 CONFIG_LCD_HEARTBEAT - update a character position on
345 the LCD display every second with
348 - Marvell Family Member
349 CONFIG_SYS_MVFS - define it if you want to enable
350 multiple fs option at one time
351 for marvell soc family
353 - 8xx CPU Options: (if using an MPC8xx CPU)
354 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
355 get_gclk_freq() cannot work
356 e.g. if there is no 32KHz
357 reference PIT/RTC clock
358 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
361 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
362 CONFIG_SYS_8xx_CPUCLK_MIN
363 CONFIG_SYS_8xx_CPUCLK_MAX
364 CONFIG_8xx_CPUCLK_DEFAULT
365 See doc/README.MPC866
367 CONFIG_SYS_MEASURE_CPUCLK
369 Define this to measure the actual CPU clock instead
370 of relying on the correctness of the configured
371 values. Mostly useful for board bringup to make sure
372 the PLL is locked at the intended frequency. Note
373 that this requires a (stable) reference clock (32 kHz
374 RTC clock or CONFIG_SYS_8XX_XIN)
376 CONFIG_SYS_DELAYED_ICACHE
378 Define this option if you want to enable the
379 ICache only when Code runs from RAM.
384 Specifies that the core is a 64-bit PowerPC implementation (implements
385 the "64" category of the Power ISA). This is necessary for ePAPR
386 compliance, among other possible reasons.
388 CONFIG_SYS_FSL_TBCLK_DIV
390 Defines the core time base clock divider ratio compared to the
391 system clock. On most PQ3 devices this is 8, on newer QorIQ
392 devices it can be 16 or 32. The ratio varies from SoC to Soc.
394 CONFIG_SYS_FSL_PCIE_COMPAT
396 Defines the string to utilize when trying to match PCIe device
397 tree nodes for the given platform.
399 CONFIG_SYS_PPC_E500_DEBUG_TLB
401 Enables a temporary TLB entry to be used during boot to work
402 around limitations in e500v1 and e500v2 external debugger
403 support. This reduces the portions of the boot code where
404 breakpoints and single stepping do not work. The value of this
405 symbol should be set to the TLB1 entry to be used for this
408 CONFIG_SYS_FSL_ERRATUM_A004510
410 Enables a workaround for erratum A004510. If set,
411 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
414 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
415 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
417 Defines one or two SoC revisions (low 8 bits of SVR)
418 for which the A004510 workaround should be applied.
420 The rest of SVR is either not relevant to the decision
421 of whether the erratum is present (e.g. p2040 versus
422 p2041) or is implied by the build target, which controls
423 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
425 See Freescale App Note 4493 for more information about
428 CONFIG_A003399_NOR_WORKAROUND
429 Enables a workaround for IFC erratum A003399. It is only
430 required during NOR boot.
432 CONFIG_A008044_WORKAROUND
433 Enables a workaround for T1040/T1042 erratum A008044. It is only
434 required during NAND boot and valid for Rev 1.0 SoC revision
436 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
438 This is the value to write into CCSR offset 0x18600
439 according to the A004510 workaround.
441 CONFIG_SYS_FSL_DSP_DDR_ADDR
442 This value denotes start offset of DDR memory which is
443 connected exclusively to the DSP cores.
445 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
446 This value denotes start offset of M2 memory
447 which is directly connected to the DSP core.
449 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
450 This value denotes start offset of M3 memory which is directly
451 connected to the DSP core.
453 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
454 This value denotes start offset of DSP CCSR space.
456 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
457 Single Source Clock is clocking mode present in some of FSL SoC's.
458 In this mode, a single differential clock is used to supply
459 clocks to the sysclock, ddrclock and usbclock.
461 CONFIG_SYS_CPC_REINIT_F
462 This CONFIG is defined when the CPC is configured as SRAM at the
463 time of U-Boot entry and is required to be re-initialized.
466 Indicates this SoC supports deep sleep feature. If deep sleep is
467 supported, core will start to execute uboot when wakes up.
469 - Generic CPU options:
470 CONFIG_SYS_GENERIC_GLOBAL_DATA
471 Defines global data is initialized in generic board board_init_f().
472 If this macro is defined, global data is created and cleared in
473 generic board board_init_f(). Without this macro, architecture/board
474 should initialize global data before calling board_init_f().
476 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
478 Defines the endianess of the CPU. Implementation of those
479 values is arch specific.
482 Freescale DDR driver in use. This type of DDR controller is
483 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
486 CONFIG_SYS_FSL_DDR_ADDR
487 Freescale DDR memory-mapped register base.
489 CONFIG_SYS_FSL_DDR_EMU
490 Specify emulator support for DDR. Some DDR features such as
491 deskew training are not available.
493 CONFIG_SYS_FSL_DDRC_GEN1
494 Freescale DDR1 controller.
496 CONFIG_SYS_FSL_DDRC_GEN2
497 Freescale DDR2 controller.
499 CONFIG_SYS_FSL_DDRC_GEN3
500 Freescale DDR3 controller.
502 CONFIG_SYS_FSL_DDRC_GEN4
503 Freescale DDR4 controller.
505 CONFIG_SYS_FSL_DDRC_ARM_GEN3
506 Freescale DDR3 controller for ARM-based SoCs.
509 Board config to use DDR1. It can be enabled for SoCs with
510 Freescale DDR1 or DDR2 controllers, depending on the board
514 Board config to use DDR2. It can be enabled for SoCs with
515 Freescale DDR2 or DDR3 controllers, depending on the board
519 Board config to use DDR3. It can be enabled for SoCs with
520 Freescale DDR3 or DDR3L controllers.
523 Board config to use DDR3L. It can be enabled for SoCs with
527 Board config to use DDR4. It can be enabled for SoCs with
530 CONFIG_SYS_FSL_IFC_BE
531 Defines the IFC controller register space as Big Endian
533 CONFIG_SYS_FSL_IFC_LE
534 Defines the IFC controller register space as Little Endian
536 CONFIG_SYS_FSL_PBL_PBI
537 It enables addition of RCW (Power on reset configuration) in built image.
538 Please refer doc/README.pblimage for more details
540 CONFIG_SYS_FSL_PBL_RCW
541 It adds PBI(pre-boot instructions) commands in u-boot build image.
542 PBI commands can be used to configure SoC before it starts the execution.
543 Please refer doc/README.pblimage for more details
546 It adds a target to create boot binary having SPL binary in PBI format
547 concatenated with u-boot binary.
549 CONFIG_SYS_FSL_DDR_BE
550 Defines the DDR controller register space as Big Endian
552 CONFIG_SYS_FSL_DDR_LE
553 Defines the DDR controller register space as Little Endian
555 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
556 Physical address from the view of DDR controllers. It is the
557 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
558 it could be different for ARM SoCs.
560 CONFIG_SYS_FSL_DDR_INTLV_256B
561 DDR controller interleaving on 256-byte. This is a special
562 interleaving mode, handled by Dickens for Freescale layerscape
565 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
566 Number of controllers used as main memory.
568 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
569 Number of controllers used for other than main memory.
571 CONFIG_SYS_FSL_HAS_DP_DDR
572 Defines the SoC has DP-DDR used for DPAA.
574 CONFIG_SYS_FSL_SEC_BE
575 Defines the SEC controller register space as Big Endian
577 CONFIG_SYS_FSL_SEC_LE
578 Defines the SEC controller register space as Little Endian
580 - Intel Monahans options:
581 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
583 Defines the Monahans run mode to oscillator
584 ratio. Valid values are 8, 16, 24, 31. The core
585 frequency is this value multiplied by 13 MHz.
587 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
589 Defines the Monahans turbo mode to oscillator
590 ratio. Valid values are 1 (default if undefined) and
591 2. The core frequency as calculated above is multiplied
595 CONFIG_SYS_INIT_SP_OFFSET
597 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
598 pointer. This is needed for the temporary stack before
601 CONFIG_SYS_MIPS_CACHE_MODE
603 Cache operation mode for the MIPS CPU.
604 See also arch/mips/include/asm/mipsregs.h.
606 CONF_CM_CACHABLE_NO_WA
609 CONF_CM_CACHABLE_NONCOHERENT
613 CONF_CM_CACHABLE_ACCELERATED
615 CONFIG_SYS_XWAY_EBU_BOOTCFG
617 Special option for Lantiq XWAY SoCs for booting from NOR flash.
618 See also arch/mips/cpu/mips32/start.S.
620 CONFIG_XWAY_SWAP_BYTES
622 Enable compilation of tools/xway-swap-bytes needed for Lantiq
623 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
624 be swapped if a flash programmer is used.
627 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
629 Select high exception vectors of the ARM core, e.g., do not
630 clear the V bit of the c1 register of CP15.
632 CONFIG_SYS_THUMB_BUILD
634 Use this flag to build U-Boot using the Thumb instruction
635 set for ARM architectures. Thumb instruction set provides
636 better code density. For ARM architectures that support
637 Thumb2 this flag will result in Thumb2 code generated by
640 CONFIG_ARM_ERRATA_716044
641 CONFIG_ARM_ERRATA_742230
642 CONFIG_ARM_ERRATA_743622
643 CONFIG_ARM_ERRATA_751472
644 CONFIG_ARM_ERRATA_761320
645 CONFIG_ARM_ERRATA_773022
646 CONFIG_ARM_ERRATA_774769
647 CONFIG_ARM_ERRATA_794072
649 If set, the workarounds for these ARM errata are applied early
650 during U-Boot startup. Note that these options force the
651 workarounds to be applied; no CPU-type/version detection
652 exists, unlike the similar options in the Linux kernel. Do not
653 set these options unless they apply!
656 Generic timer clock source frequency.
658 COUNTER_FREQUENCY_REAL
659 Generic timer clock source frequency if the real clock is
660 different from COUNTER_FREQUENCY, and can only be determined
663 NOTE: The following can be machine specific errata. These
664 do have ability to provide rudimentary version and machine
665 specific checks, but expect no product checks.
666 CONFIG_ARM_ERRATA_430973
667 CONFIG_ARM_ERRATA_454179
668 CONFIG_ARM_ERRATA_621766
669 CONFIG_ARM_ERRATA_798870
670 CONFIG_ARM_ERRATA_801819
673 CONFIG_TEGRA_SUPPORT_NON_SECURE
675 Support executing U-Boot in non-secure (NS) mode. Certain
676 impossible actions will be skipped if the CPU is in NS mode,
677 such as ARM architectural timer initialization.
679 - Linux Kernel Interface:
682 U-Boot stores all clock information in Hz
683 internally. For binary compatibility with older Linux
684 kernels (which expect the clocks passed in the
685 bd_info data to be in MHz) the environment variable
686 "clocks_in_mhz" can be defined so that U-Boot
687 converts clock data to MHZ before passing it to the
689 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
690 "clocks_in_mhz=1" is automatically included in the
693 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
695 When transferring memsize parameter to Linux, some versions
696 expect it to be in bytes, others in MB.
697 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
701 New kernel versions are expecting firmware settings to be
702 passed using flattened device trees (based on open firmware
706 * New libfdt-based support
707 * Adds the "fdt" command
708 * The bootm command automatically updates the fdt
710 OF_CPU - The proper name of the cpus node (only required for
711 MPC512X and MPC5xxx based boards).
712 OF_SOC - The proper name of the soc node (only required for
713 MPC512X and MPC5xxx based boards).
714 OF_TBCLK - The timebase frequency.
715 OF_STDOUT_PATH - The path to the console device
717 boards with QUICC Engines require OF_QE to set UCC MAC
720 CONFIG_OF_BOARD_SETUP
722 Board code has addition modification that it wants to make
723 to the flat device tree before handing it off to the kernel
725 CONFIG_OF_SYSTEM_SETUP
727 Other code has addition modification that it wants to make
728 to the flat device tree before handing it off to the kernel.
729 This causes ft_system_setup() to be called before booting
734 This define fills in the correct boot CPU in the boot
735 param header, the default value is zero if undefined.
739 U-Boot can detect if an IDE device is present or not.
740 If not, and this new config option is activated, U-Boot
741 removes the ATA node from the DTS before booting Linux,
742 so the Linux IDE driver does not probe the device and
743 crash. This is needed for buggy hardware (uc101) where
744 no pull down resistor is connected to the signal IDE5V_DD7.
746 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
748 This setting is mandatory for all boards that have only one
749 machine type and must be used to specify the machine type
750 number as it appears in the ARM machine registry
751 (see http://www.arm.linux.org.uk/developer/machines/).
752 Only boards that have multiple machine types supported
753 in a single configuration file and the machine type is
754 runtime discoverable, do not have to use this setting.
756 - vxWorks boot parameters:
758 bootvx constructs a valid bootline using the following
759 environments variables: bootdev, bootfile, ipaddr, netmask,
760 serverip, gatewayip, hostname, othbootargs.
761 It loads the vxWorks image pointed bootfile.
763 Note: If a "bootargs" environment is defined, it will overwride
764 the defaults discussed just above.
766 - Cache Configuration:
767 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
768 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
769 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
771 - Cache Configuration for ARM:
772 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
774 CONFIG_SYS_PL310_BASE - Physical base address of PL310
775 controller register space
780 Define this if you want support for Amba PrimeCell PL010 UARTs.
784 Define this if you want support for Amba PrimeCell PL011 UARTs.
788 If you have Amba PrimeCell PL011 UARTs, set this variable to
789 the clock speed of the UARTs.
793 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
794 define this to a list of base addresses for each (supported)
795 port. See e.g. include/configs/versatile.h
797 CONFIG_SERIAL_HW_FLOW_CONTROL
799 Define this variable to enable hw flow control in serial driver.
800 Current user of this option is drivers/serial/nsl16550.c driver
803 Depending on board, define exactly one serial port
804 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
805 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
806 console by defining CONFIG_8xx_CONS_NONE
808 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
809 port routines must be defined elsewhere
810 (i.e. serial_init(), serial_getc(), ...)
813 Enables console device for a color framebuffer. Needs following
814 defines (cf. smiLynxEM, i8042)
815 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
817 VIDEO_HW_RECTFILL graphic chip supports
820 VIDEO_HW_BITBLT graphic chip supports
821 bit-blit (cf. smiLynxEM)
822 VIDEO_VISIBLE_COLS visible pixel columns
824 VIDEO_VISIBLE_ROWS visible pixel rows
825 VIDEO_PIXEL_SIZE bytes per pixel
826 VIDEO_DATA_FORMAT graphic data format
827 (0-5, cf. cfb_console.c)
828 VIDEO_FB_ADRS framebuffer address
829 VIDEO_KBD_INIT_FCT keyboard int fct
830 (i.e. rx51_kp_init())
831 VIDEO_TSTC_FCT test char fct
833 VIDEO_GETC_FCT get char fct
835 CONFIG_VIDEO_LOGO display Linux logo in
837 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
838 linux_logo.h for logo.
839 Requires CONFIG_VIDEO_LOGO
840 CONFIG_CONSOLE_EXTRA_INFO
841 additional board info beside
844 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
845 a limited number of ANSI escape sequences (cursor control,
846 erase functions and limited graphics rendition control).
848 When CONFIG_CFB_CONSOLE is defined, video console is
849 default i/o. Serial console can be forced with
850 environment 'console=serial'.
852 When CONFIG_SILENT_CONSOLE is defined, all console
853 messages (by U-Boot and Linux!) can be silenced with
854 the "silent" environment variable. See
855 doc/README.silent for more information.
857 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
859 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
863 CONFIG_BAUDRATE - in bps
864 Select one of the baudrates listed in
865 CONFIG_SYS_BAUDRATE_TABLE, see below.
866 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
868 - Console Rx buffer length
869 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
870 the maximum receive buffer length for the SMC.
871 This option is actual only for 82xx and 8xx possible.
872 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
873 must be defined, to setup the maximum idle timeout for
876 - Pre-Console Buffer:
877 Prior to the console being initialised (i.e. serial UART
878 initialised etc) all console output is silently discarded.
879 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
880 buffer any console messages prior to the console being
881 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
882 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
883 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
884 bytes are output before the console is initialised, the
885 earlier bytes are discarded.
887 Note that when printing the buffer a copy is made on the
888 stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack.
890 'Sane' compilers will generate smaller code if
891 CONFIG_PRE_CON_BUF_SZ is a power of 2
895 Only needed when CONFIG_BOOTDELAY is enabled;
896 define a command string that is automatically executed
897 when no character is read on the console interface
898 within "Boot Delay" after reset.
901 This can be used to pass arguments to the bootm
902 command. The value of CONFIG_BOOTARGS goes into the
903 environment value "bootargs".
905 CONFIG_RAMBOOT and CONFIG_NFSBOOT
906 The value of these goes into the environment as
907 "ramboot" and "nfsboot" respectively, and can be used
908 as a convenience, when switching between booting from
912 CONFIG_BOOTCOUNT_LIMIT
913 Implements a mechanism for detecting a repeating reboot
915 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
918 If no softreset save registers are found on the hardware
919 "bootcount" is stored in the environment. To prevent a
920 saveenv on all reboots, the environment variable
921 "upgrade_available" is used. If "upgrade_available" is
922 0, "bootcount" is always 0, if "upgrade_available" is
923 1 "bootcount" is incremented in the environment.
924 So the Userspace Applikation must set the "upgrade_available"
925 and "bootcount" variable to 0, if a boot was successfully.
930 When this option is #defined, the existence of the
931 environment variable "preboot" will be checked
932 immediately before starting the CONFIG_BOOTDELAY
933 countdown and/or running the auto-boot command resp.
934 entering interactive mode.
936 This feature is especially useful when "preboot" is
937 automatically generated or modified. For an example
938 see the LWMON board specific code: here "preboot" is
939 modified when the user holds down a certain
940 combination of keys on the (special) keyboard when
943 - Serial Download Echo Mode:
945 If defined to 1, all characters received during a
946 serial download (using the "loads" command) are
947 echoed back. This might be needed by some terminal
948 emulations (like "cu"), but may as well just take
949 time on others. This setting #define's the initial
950 value of the "loads_echo" environment variable.
952 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
954 Select one of the baudrates listed in
955 CONFIG_SYS_BAUDRATE_TABLE, see below.
958 Monitor commands can be included or excluded
959 from the build by using the #include files
960 <config_cmd_all.h> and #undef'ing unwanted
961 commands, or adding #define's for wanted commands.
963 The default command configuration includes all commands
964 except those marked below with a "*".
966 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
967 CONFIG_CMD_ASKENV * ask for env variable
968 CONFIG_CMD_BDI bdinfo
969 CONFIG_CMD_BEDBUG * Include BedBug Debugger
970 CONFIG_CMD_BMP * BMP support
971 CONFIG_CMD_BSP * Board specific commands
972 CONFIG_CMD_BOOTD bootd
973 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
974 CONFIG_CMD_CACHE * icache, dcache
975 CONFIG_CMD_CLK * clock command support
976 CONFIG_CMD_CONSOLE coninfo
977 CONFIG_CMD_CRC32 * crc32
978 CONFIG_CMD_DATE * support for RTC, date/time...
979 CONFIG_CMD_DHCP * DHCP support
980 CONFIG_CMD_DIAG * Diagnostics
981 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
982 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
983 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
984 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
985 CONFIG_CMD_DTT * Digital Therm and Thermostat
986 CONFIG_CMD_ECHO echo arguments
987 CONFIG_CMD_EDITENV edit env variable
988 CONFIG_CMD_EEPROM * EEPROM read/write support
989 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands
990 CONFIG_CMD_ELF * bootelf, bootvx
991 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
992 CONFIG_CMD_ENV_FLAGS * display details about env flags
993 CONFIG_CMD_ENV_EXISTS * check existence of env variable
994 CONFIG_CMD_EXPORTENV * export the environment
995 CONFIG_CMD_EXT2 * ext2 command support
996 CONFIG_CMD_EXT4 * ext4 command support
997 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
998 that work for multiple fs types
999 CONFIG_CMD_FS_UUID * Look up a filesystem UUID
1000 CONFIG_CMD_SAVEENV saveenv
1001 CONFIG_CMD_FDC * Floppy Disk Support
1002 CONFIG_CMD_FAT * FAT command support
1003 CONFIG_CMD_FLASH flinfo, erase, protect
1004 CONFIG_CMD_FPGA FPGA device initialization support
1005 CONFIG_CMD_FUSE * Device fuse support
1006 CONFIG_CMD_GETTIME * Get time since boot
1007 CONFIG_CMD_GO * the 'go' command (exec code)
1008 CONFIG_CMD_GREPENV * search environment
1009 CONFIG_CMD_HASH * calculate hash / digest
1010 CONFIG_CMD_I2C * I2C serial bus support
1011 CONFIG_CMD_IDE * IDE harddisk support
1012 CONFIG_CMD_IMI iminfo
1013 CONFIG_CMD_IMLS List all images found in NOR flash
1014 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
1015 CONFIG_CMD_IMMAP * IMMR dump support
1016 CONFIG_CMD_IOTRACE * I/O tracing for debugging
1017 CONFIG_CMD_IMPORTENV * import an environment
1018 CONFIG_CMD_INI * import data from an ini file into the env
1019 CONFIG_CMD_IRQ * irqinfo
1020 CONFIG_CMD_ITEST Integer/string test of 2 values
1021 CONFIG_CMD_JFFS2 * JFFS2 Support
1022 CONFIG_CMD_KGDB * kgdb
1023 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
1024 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
1026 CONFIG_CMD_LOADB loadb
1027 CONFIG_CMD_LOADS loads
1028 CONFIG_CMD_MD5SUM * print md5 message digest
1029 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
1030 CONFIG_CMD_MEMINFO * Display detailed memory information
1031 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
1033 CONFIG_CMD_MEMTEST * mtest
1034 CONFIG_CMD_MISC Misc functions like sleep etc
1035 CONFIG_CMD_MMC * MMC memory mapped support
1036 CONFIG_CMD_MII * MII utility commands
1037 CONFIG_CMD_MTDPARTS * MTD partition support
1038 CONFIG_CMD_NAND * NAND support
1039 CONFIG_CMD_NET bootp, tftpboot, rarpboot
1040 CONFIG_CMD_NFS NFS support
1041 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
1042 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
1043 CONFIG_CMD_PCI * pciinfo
1044 CONFIG_CMD_PCMCIA * PCMCIA support
1045 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
1047 CONFIG_CMD_PORTIO * Port I/O
1048 CONFIG_CMD_READ * Read raw data from partition
1049 CONFIG_CMD_REGINFO * Register dump
1050 CONFIG_CMD_RUN run command in env variable
1051 CONFIG_CMD_SANDBOX * sb command to access sandbox features
1052 CONFIG_CMD_SAVES * save S record dump
1053 CONFIG_SCSI * SCSI Support
1054 CONFIG_CMD_SDRAM * print SDRAM configuration information
1055 (requires CONFIG_CMD_I2C)
1056 CONFIG_CMD_SETGETDCR Support for DCR Register access
1058 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
1059 CONFIG_CMD_SHA1SUM * print sha1 memory digest
1060 (requires CONFIG_CMD_MEMORY)
1061 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
1062 CONFIG_CMD_SOURCE "source" command Support
1063 CONFIG_CMD_SPI * SPI serial bus support
1064 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1065 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
1066 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
1067 CONFIG_CMD_TIMER * access to the system tick timer
1068 CONFIG_CMD_USB * USB support
1069 CONFIG_CMD_CDP * Cisco Discover Protocol support
1070 CONFIG_CMD_MFSL * Microblaze FSL support
1071 CONFIG_CMD_XIMG Load part of Multi Image
1072 CONFIG_CMD_UUID * Generate random UUID or GUID string
1074 EXAMPLE: If you want all functions except of network
1075 support you can write:
1077 #include "config_cmd_all.h"
1078 #undef CONFIG_CMD_NET
1081 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
1083 Note: Don't enable the "icache" and "dcache" commands
1084 (configuration option CONFIG_CMD_CACHE) unless you know
1085 what you (and your U-Boot users) are doing. Data
1086 cache cannot be enabled on systems like the 8xx or
1087 8260 (where accesses to the IMMR region must be
1088 uncached), and it cannot be disabled on all other
1089 systems where we (mis-) use the data cache to hold an
1090 initial stack and some data.
1093 XXX - this list needs to get updated!
1095 - Removal of commands
1096 If no commands are needed to boot, you can disable
1097 CONFIG_CMDLINE to remove them. In this case, the command line
1098 will not be available, and when U-Boot wants to execute the
1099 boot command (on start-up) it will call board_run_command()
1100 instead. This can reduce image size significantly for very
1101 simple boot procedures.
1103 - Regular expression support:
1105 If this variable is defined, U-Boot is linked against
1106 the SLRE (Super Light Regular Expression) library,
1107 which adds regex support to some commands, as for
1108 example "env grep" and "setexpr".
1112 If this variable is defined, U-Boot will use a device tree
1113 to configure its devices, instead of relying on statically
1114 compiled #defines in the board file. This option is
1115 experimental and only available on a few boards. The device
1116 tree is available in the global data as gd->fdt_blob.
1118 U-Boot needs to get its device tree from somewhere. This can
1119 be done using one of the two options below:
1122 If this variable is defined, U-Boot will embed a device tree
1123 binary in its image. This device tree file should be in the
1124 board directory and called <soc>-<board>.dts. The binary file
1125 is then picked up in board_init_f() and made available through
1126 the global data structure as gd->blob.
1129 If this variable is defined, U-Boot will build a device tree
1130 binary. It will be called u-boot.dtb. Architecture-specific
1131 code will locate it at run-time. Generally this works by:
1133 cat u-boot.bin u-boot.dtb >image.bin
1135 and in fact, U-Boot does this for you, creating a file called
1136 u-boot-dtb.bin which is useful in the common case. You can
1137 still use the individual files if you need something more
1142 If this variable is defined, it enables watchdog
1143 support for the SoC. There must be support in the SoC
1144 specific code for a watchdog. For the 8xx and 8260
1145 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1146 register. When supported for a specific SoC is
1147 available, then no further board specific code should
1148 be needed to use it.
1151 When using a watchdog circuitry external to the used
1152 SoC, then define this variable and provide board
1153 specific code for the "hw_watchdog_reset" function.
1155 CONFIG_AT91_HW_WDT_TIMEOUT
1156 specify the timeout in seconds. default 2 seconds.
1159 CONFIG_VERSION_VARIABLE
1160 If this variable is defined, an environment variable
1161 named "ver" is created by U-Boot showing the U-Boot
1162 version as printed by the "version" command.
1163 Any change to this variable will be reverted at the
1168 When CONFIG_CMD_DATE is selected, the type of the RTC
1169 has to be selected, too. Define exactly one of the
1172 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1173 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1174 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1175 CONFIG_RTC_MC146818 - use MC146818 RTC
1176 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1177 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1178 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1179 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
1180 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1181 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1182 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1183 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1184 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1187 Note that if the RTC uses I2C, then the I2C interface
1188 must also be configured. See I2C Support, below.
1191 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1193 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1194 chip-ngpio pairs that tell the PCA953X driver the number of
1195 pins supported by a particular chip.
1197 Note that if the GPIO device uses I2C, then the I2C interface
1198 must also be configured. See I2C Support, below.
1201 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
1202 accesses and can checksum them or write a list of them out
1203 to memory. See the 'iotrace' command for details. This is
1204 useful for testing device drivers since it can confirm that
1205 the driver behaves the same way before and after a code
1206 change. Currently this is supported on sandbox and arm. To
1207 add support for your architecture, add '#include <iotrace.h>'
1208 to the bottom of arch/<arch>/include/asm/io.h and test.
1210 Example output from the 'iotrace stats' command is below.
1211 Note that if the trace buffer is exhausted, the checksum will
1212 still continue to operate.
1215 Start: 10000000 (buffer start address)
1216 Size: 00010000 (buffer size)
1217 Offset: 00000120 (current buffer offset)
1218 Output: 10000120 (start + offset)
1219 Count: 00000018 (number of trace records)
1220 CRC32: 9526fb66 (CRC32 of all trace records)
1222 - Timestamp Support:
1224 When CONFIG_TIMESTAMP is selected, the timestamp
1225 (date and time) of an image is printed by image
1226 commands like bootm or iminfo. This option is
1227 automatically enabled when you select CONFIG_CMD_DATE .
1229 - Partition Labels (disklabels) Supported:
1230 Zero or more of the following:
1231 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1232 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1233 Intel architecture, USB sticks, etc.
1234 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1235 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1236 bootloader. Note 2TB partition limit; see
1238 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1240 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1241 CONFIG_SCSI) you must configure support for at
1242 least one non-MTD partition type as well.
1245 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1246 board configurations files but used nowhere!
1248 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1249 be performed by calling the function
1250 ide_set_reset(int reset)
1251 which has to be defined in a board specific file
1256 Set this to enable ATAPI support.
1261 Set this to enable support for disks larger than 137GB
1262 Also look at CONFIG_SYS_64BIT_LBA.
1263 Whithout these , LBA48 support uses 32bit variables and will 'only'
1264 support disks up to 2.1TB.
1266 CONFIG_SYS_64BIT_LBA:
1267 When enabled, makes the IDE subsystem use 64bit sector addresses.
1271 At the moment only there is only support for the
1272 SYM53C8XX SCSI controller; define
1273 CONFIG_SCSI_SYM53C8XX to enable it.
1275 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1276 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1277 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1278 maximum numbers of LUNs, SCSI ID's and target
1280 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1282 The environment variable 'scsidevs' is set to the number of
1283 SCSI devices found during the last scan.
1285 - NETWORK Support (PCI):
1287 Support for Intel 8254x/8257x gigabit chips.
1290 Utility code for direct access to the SPI bus on Intel 8257x.
1291 This does not do anything useful unless you set at least one
1292 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1294 CONFIG_E1000_SPI_GENERIC
1295 Allow generic access to the SPI bus on the Intel 8257x, for
1296 example with the "sspi" command.
1299 Management command for E1000 devices. When used on devices
1300 with SPI support you can reprogram the EEPROM from U-Boot.
1303 Support for Intel 82557/82559/82559ER chips.
1304 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1305 write routine for first time initialisation.
1308 Support for Digital 2114x chips.
1309 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1310 modem chip initialisation (KS8761/QS6611).
1313 Support for National dp83815 chips.
1316 Support for National dp8382[01] gigabit chips.
1318 - NETWORK Support (other):
1320 CONFIG_DRIVER_AT91EMAC
1321 Support for AT91RM9200 EMAC.
1324 Define this to use reduced MII inteface
1326 CONFIG_DRIVER_AT91EMAC_QUIET
1327 If this defined, the driver is quiet.
1328 The driver doen't show link status messages.
1330 CONFIG_CALXEDA_XGMAC
1331 Support for the Calxeda XGMAC device
1334 Support for SMSC's LAN91C96 chips.
1336 CONFIG_LAN91C96_BASE
1337 Define this to hold the physical address
1338 of the LAN91C96's I/O space
1340 CONFIG_LAN91C96_USE_32_BIT
1341 Define this to enable 32 bit addressing
1344 Support for SMSC's LAN91C111 chip
1346 CONFIG_SMC91111_BASE
1347 Define this to hold the physical address
1348 of the device (I/O space)
1350 CONFIG_SMC_USE_32_BIT
1351 Define this if data bus is 32 bits
1353 CONFIG_SMC_USE_IOFUNCS
1354 Define this to use i/o functions instead of macros
1355 (some hardware wont work with macros)
1357 CONFIG_DRIVER_TI_EMAC
1358 Support for davinci emac
1360 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1361 Define this if you have more then 3 PHYs.
1364 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1366 CONFIG_FTGMAC100_EGIGA
1367 Define this to use GE link update with gigabit PHY.
1368 Define this if FTGMAC100 is connected to gigabit PHY.
1369 If your system has 10/100 PHY only, it might not occur
1370 wrong behavior. Because PHY usually return timeout or
1371 useless data when polling gigabit status and gigabit
1372 control registers. This behavior won't affect the
1373 correctnessof 10/100 link speed update.
1376 Support for SMSC's LAN911x and LAN921x chips
1379 Define this to hold the physical address
1380 of the device (I/O space)
1382 CONFIG_SMC911X_32_BIT
1383 Define this if data bus is 32 bits
1385 CONFIG_SMC911X_16_BIT
1386 Define this if data bus is 16 bits. If your processor
1387 automatically converts one 32 bit word to two 16 bit
1388 words you may also try CONFIG_SMC911X_32_BIT.
1391 Support for Renesas on-chip Ethernet controller
1393 CONFIG_SH_ETHER_USE_PORT
1394 Define the number of ports to be used
1396 CONFIG_SH_ETHER_PHY_ADDR
1397 Define the ETH PHY's address
1399 CONFIG_SH_ETHER_CACHE_WRITEBACK
1400 If this option is set, the driver enables cache flush.
1404 Support for PWM modul on the imx6.
1408 Support TPM devices.
1410 CONFIG_TPM_TIS_INFINEON
1411 Support for Infineon i2c bus TPM devices. Only one device
1412 per system is supported at this time.
1414 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1415 Define the burst count bytes upper limit
1418 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
1420 CONFIG_TPM_ST33ZP24_I2C
1421 Support for STMicroelectronics ST33ZP24 I2C devices.
1422 Requires TPM_ST33ZP24 and I2C.
1424 CONFIG_TPM_ST33ZP24_SPI
1425 Support for STMicroelectronics ST33ZP24 SPI devices.
1426 Requires TPM_ST33ZP24 and SPI.
1428 CONFIG_TPM_ATMEL_TWI
1429 Support for Atmel TWI TPM device. Requires I2C support.
1432 Support for generic parallel port TPM devices. Only one device
1433 per system is supported at this time.
1435 CONFIG_TPM_TIS_BASE_ADDRESS
1436 Base address where the generic TPM device is mapped
1437 to. Contemporary x86 systems usually map it at
1441 Add tpm monitor functions.
1442 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1443 provides monitor access to authorized functions.
1446 Define this to enable the TPM support library which provides
1447 functional interfaces to some TPM commands.
1448 Requires support for a TPM device.
1450 CONFIG_TPM_AUTH_SESSIONS
1451 Define this to enable authorized functions in the TPM library.
1452 Requires CONFIG_TPM and CONFIG_SHA1.
1455 At the moment only the UHCI host controller is
1456 supported (PIP405, MIP405, MPC5200); define
1457 CONFIG_USB_UHCI to enable it.
1458 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1459 and define CONFIG_USB_STORAGE to enable the USB
1462 Supported are USB Keyboards and USB Floppy drives
1464 MPC5200 USB requires additional defines:
1466 for 528 MHz Clock: 0x0001bbbb
1470 for differential drivers: 0x00001000
1471 for single ended drivers: 0x00005000
1472 for differential drivers on PSC3: 0x00000100
1473 for single ended drivers on PSC3: 0x00004100
1474 CONFIG_SYS_USB_EVENT_POLL
1475 May be defined to allow interrupt polling
1476 instead of using asynchronous interrupts
1478 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1479 txfilltuning field in the EHCI controller on reset.
1481 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1482 HW module registers.
1485 Define the below if you wish to use the USB console.
1486 Once firmware is rebuilt from a serial console issue the
1487 command "setenv stdin usbtty; setenv stdout usbtty" and
1488 attach your USB cable. The Unix command "dmesg" should print
1489 it has found a new device. The environment variable usbtty
1490 can be set to gserial or cdc_acm to enable your device to
1491 appear to a USB host as a Linux gserial device or a
1492 Common Device Class Abstract Control Model serial device.
1493 If you select usbtty = gserial you should be able to enumerate
1495 # modprobe usbserial vendor=0xVendorID product=0xProductID
1496 else if using cdc_acm, simply setting the environment
1497 variable usbtty to be cdc_acm should suffice. The following
1498 might be defined in YourBoardName.h
1501 Define this to build a UDC device
1504 Define this to have a tty type of device available to
1505 talk to the UDC device
1508 Define this to enable the high speed support for usb
1509 device and usbtty. If this feature is enabled, a routine
1510 int is_usbd_high_speed(void)
1511 also needs to be defined by the driver to dynamically poll
1512 whether the enumeration has succeded at high speed or full
1515 CONFIG_SYS_CONSOLE_IS_IN_ENV
1516 Define this if you want stdin, stdout &/or stderr to
1520 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1521 Derive USB clock from external clock "blah"
1522 - CONFIG_SYS_USB_EXTC_CLK 0x02
1524 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1525 Derive USB clock from brgclk
1526 - CONFIG_SYS_USB_BRG_CLK 0x04
1528 If you have a USB-IF assigned VendorID then you may wish to
1529 define your own vendor specific values either in BoardName.h
1530 or directly in usbd_vendor_info.h. If you don't define
1531 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1532 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1533 should pretend to be a Linux device to it's target host.
1535 CONFIG_USBD_MANUFACTURER
1536 Define this string as the name of your company for
1537 - CONFIG_USBD_MANUFACTURER "my company"
1539 CONFIG_USBD_PRODUCT_NAME
1540 Define this string as the name of your product
1541 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1543 CONFIG_USBD_VENDORID
1544 Define this as your assigned Vendor ID from the USB
1545 Implementors Forum. This *must* be a genuine Vendor ID
1546 to avoid polluting the USB namespace.
1547 - CONFIG_USBD_VENDORID 0xFFFF
1549 CONFIG_USBD_PRODUCTID
1550 Define this as the unique Product ID
1552 - CONFIG_USBD_PRODUCTID 0xFFFF
1554 - ULPI Layer Support:
1555 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1556 the generic ULPI layer. The generic layer accesses the ULPI PHY
1557 via the platform viewport, so you need both the genric layer and
1558 the viewport enabled. Currently only Chipidea/ARC based
1559 viewport is supported.
1560 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1561 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1562 If your ULPI phy needs a different reference clock than the
1563 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1564 the appropriate value in Hz.
1567 The MMC controller on the Intel PXA is supported. To
1568 enable this define CONFIG_MMC. The MMC can be
1569 accessed from the boot prompt by mapping the device
1570 to physical memory similar to flash. Command line is
1571 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1572 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1575 Support for Renesas on-chip MMCIF controller
1577 CONFIG_SH_MMCIF_ADDR
1578 Define the base address of MMCIF registers
1581 Define the clock frequency for MMCIF
1584 Enable the generic MMC driver
1586 CONFIG_SUPPORT_EMMC_BOOT
1587 Enable some additional features of the eMMC boot partitions.
1589 CONFIG_SUPPORT_EMMC_RPMB
1590 Enable the commands for reading, writing and programming the
1591 key for the Replay Protection Memory Block partition in eMMC.
1593 - USB Device Firmware Update (DFU) class support:
1594 CONFIG_USB_FUNCTION_DFU
1595 This enables the USB portion of the DFU USB class
1598 This enables the command "dfu" which is used to have
1599 U-Boot create a DFU class device via USB. This command
1600 requires that the "dfu_alt_info" environment variable be
1601 set and define the alt settings to expose to the host.
1604 This enables support for exposing (e)MMC devices via DFU.
1607 This enables support for exposing NAND devices via DFU.
1610 This enables support for exposing RAM via DFU.
1611 Note: DFU spec refer to non-volatile memory usage, but
1612 allow usages beyond the scope of spec - here RAM usage,
1613 one that would help mostly the developer.
1615 CONFIG_SYS_DFU_DATA_BUF_SIZE
1616 Dfu transfer uses a buffer before writing data to the
1617 raw storage device. Make the size (in bytes) of this buffer
1618 configurable. The size of this buffer is also configurable
1619 through the "dfu_bufsiz" environment variable.
1621 CONFIG_SYS_DFU_MAX_FILE_SIZE
1622 When updating files rather than the raw storage device,
1623 we use a static buffer to copy the file into and then write
1624 the buffer once we've been given the whole file. Define
1625 this to the maximum filesize (in bytes) for the buffer.
1626 Default is 4 MiB if undefined.
1628 DFU_DEFAULT_POLL_TIMEOUT
1629 Poll timeout [ms], is the timeout a device can send to the
1630 host. The host must wait for this timeout before sending
1631 a subsequent DFU_GET_STATUS request to the device.
1633 DFU_MANIFEST_POLL_TIMEOUT
1634 Poll timeout [ms], which the device sends to the host when
1635 entering dfuMANIFEST state. Host waits this timeout, before
1636 sending again an USB request to the device.
1638 - USB Device Android Fastboot support:
1639 CONFIG_USB_FUNCTION_FASTBOOT
1640 This enables the USB part of the fastboot gadget
1643 This enables the command "fastboot" which enables the Android
1644 fastboot mode for the platform's USB device. Fastboot is a USB
1645 protocol for downloading images, flashing and device control
1646 used on Android devices.
1647 See doc/README.android-fastboot for more information.
1649 CONFIG_ANDROID_BOOT_IMAGE
1650 This enables support for booting images which use the Android
1651 image format header.
1653 CONFIG_FASTBOOT_BUF_ADDR
1654 The fastboot protocol requires a large memory buffer for
1655 downloads. Define this to the starting RAM address to use for
1658 CONFIG_FASTBOOT_BUF_SIZE
1659 The fastboot protocol requires a large memory buffer for
1660 downloads. This buffer should be as large as possible for a
1661 platform. Define this to the size available RAM for fastboot.
1663 CONFIG_FASTBOOT_FLASH
1664 The fastboot protocol includes a "flash" command for writing
1665 the downloaded image to a non-volatile storage device. Define
1666 this to enable the "fastboot flash" command.
1668 CONFIG_FASTBOOT_FLASH_MMC_DEV
1669 The fastboot "flash" command requires additional information
1670 regarding the non-volatile storage device. Define this to
1671 the eMMC device that fastboot should use to store the image.
1673 CONFIG_FASTBOOT_GPT_NAME
1674 The fastboot "flash" command supports writing the downloaded
1675 image to the Protective MBR and the Primary GUID Partition
1676 Table. (Additionally, this downloaded image is post-processed
1677 to generate and write the Backup GUID Partition Table.)
1678 This occurs when the specified "partition name" on the
1679 "fastboot flash" command line matches this value.
1680 Default is GPT_ENTRY_NAME (currently "gpt") if undefined.
1682 - Journaling Flash filesystem support:
1683 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1684 CONFIG_JFFS2_NAND_DEV
1685 Define these for a default partition on a NAND device
1687 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1688 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1689 Define these for a default partition on a NOR device
1691 CONFIG_SYS_JFFS_CUSTOM_PART
1692 Define this to create an own partition. You have to provide a
1693 function struct part_info* jffs2_part_info(int part_num)
1695 If you define only one JFFS2 partition you may also want to
1696 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1697 to disable the command chpart. This is the default when you
1698 have not defined a custom partition
1700 - FAT(File Allocation Table) filesystem write function support:
1703 Define this to enable support for saving memory data as a
1704 file in FAT formatted partition.
1706 This will also enable the command "fatwrite" enabling the
1707 user to write files to FAT.
1709 CBFS (Coreboot Filesystem) support
1712 Define this to enable support for reading from a Coreboot
1713 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1716 - FAT(File Allocation Table) filesystem cluster size:
1717 CONFIG_FS_FAT_MAX_CLUSTSIZE
1719 Define the max cluster size for fat operations else
1720 a default value of 65536 will be defined.
1723 See Kconfig help for available keyboard drivers.
1727 Define this to enable a custom keyboard support.
1728 This simply calls drv_keyboard_init() which must be
1729 defined in your board-specific files. This option is deprecated
1730 and is only used by novena. For new boards, use driver model
1736 Define this to enable video support (for output to
1739 CONFIG_VIDEO_CT69000
1741 Enable Chips & Technologies 69000 Video chip
1743 CONFIG_VIDEO_SMI_LYNXEM
1744 Enable Silicon Motion SMI 712/710/810 Video chip. The
1745 video output is selected via environment 'videoout'
1746 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1749 For the CT69000 and SMI_LYNXEM drivers, videomode is
1750 selected via environment 'videomode'. Two different ways
1752 - "videomode=num" 'num' is a standard LiLo mode numbers.
1753 Following standard modes are supported (* is default):
1755 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1756 -------------+---------------------------------------------
1757 8 bits | 0x301* 0x303 0x305 0x161 0x307
1758 15 bits | 0x310 0x313 0x316 0x162 0x319
1759 16 bits | 0x311 0x314 0x317 0x163 0x31A
1760 24 bits | 0x312 0x315 0x318 ? 0x31B
1761 -------------+---------------------------------------------
1762 (i.e. setenv videomode 317; saveenv; reset;)
1764 - "videomode=bootargs" all the video parameters are parsed
1765 from the bootargs. (See drivers/video/videomodes.c)
1768 CONFIG_VIDEO_SED13806
1769 Enable Epson SED13806 driver. This driver supports 8bpp
1770 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1771 or CONFIG_VIDEO_SED13806_16BPP
1774 Enable the Freescale DIU video driver. Reference boards for
1775 SOCs that have a DIU should define this macro to enable DIU
1776 support, and should also define these other macros:
1782 CONFIG_VIDEO_SW_CURSOR
1783 CONFIG_VGA_AS_SINGLE_DEVICE
1785 CONFIG_VIDEO_BMP_LOGO
1787 The DIU driver will look for the 'video-mode' environment
1788 variable, and if defined, enable the DIU as a console during
1789 boot. See the documentation file doc/README.video for a
1790 description of this variable.
1792 - LCD Support: CONFIG_LCD
1794 Define this to enable LCD support (for output to LCD
1795 display); also select one of the supported displays
1796 by defining one of these:
1800 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1802 CONFIG_NEC_NL6448AC33:
1804 NEC NL6448AC33-18. Active, color, single scan.
1806 CONFIG_NEC_NL6448BC20
1808 NEC NL6448BC20-08. 6.5", 640x480.
1809 Active, color, single scan.
1811 CONFIG_NEC_NL6448BC33_54
1813 NEC NL6448BC33-54. 10.4", 640x480.
1814 Active, color, single scan.
1818 Sharp 320x240. Active, color, single scan.
1819 It isn't 16x9, and I am not sure what it is.
1821 CONFIG_SHARP_LQ64D341
1823 Sharp LQ64D341 display, 640x480.
1824 Active, color, single scan.
1828 HLD1045 display, 640x480.
1829 Active, color, single scan.
1833 Optrex CBL50840-2 NF-FW 99 22 M5
1835 Hitachi LMG6912RPFC-00T
1839 320x240. Black & white.
1841 Normally display is black on white background; define
1842 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1844 CONFIG_LCD_ALIGNMENT
1846 Normally the LCD is page-aligned (typically 4KB). If this is
1847 defined then the LCD will be aligned to this value instead.
1848 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1849 here, since it is cheaper to change data cache settings on
1850 a per-section basis.
1852 CONFIG_CONSOLE_SCROLL_LINES
1854 When the console need to be scrolled, this is the number of
1855 lines to scroll by. It defaults to 1. Increasing this makes
1856 the console jump but can help speed up operation when scrolling
1861 Sometimes, for example if the display is mounted in portrait
1862 mode or even if it's mounted landscape but rotated by 180degree,
1863 we need to rotate our content of the display relative to the
1864 framebuffer, so that user can read the messages which are
1866 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1867 initialized with a given rotation from "vl_rot" out of
1868 "vidinfo_t" which is provided by the board specific code.
1869 The value for vl_rot is coded as following (matching to
1870 fbcon=rotate:<n> linux-kernel commandline):
1871 0 = no rotation respectively 0 degree
1872 1 = 90 degree rotation
1873 2 = 180 degree rotation
1874 3 = 270 degree rotation
1876 If CONFIG_LCD_ROTATION is not defined, the console will be
1877 initialized with 0degree rotation.
1881 Support drawing of RLE8-compressed bitmaps on the LCD.
1885 Enables an 'i2c edid' command which can read EDID
1886 information over I2C from an attached LCD display.
1888 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1890 If this option is set, the environment is checked for
1891 a variable "splashimage". If found, the usual display
1892 of logo, copyright and system information on the LCD
1893 is suppressed and the BMP image at the address
1894 specified in "splashimage" is loaded instead. The
1895 console is redirected to the "nulldev", too. This
1896 allows for a "silent" boot where a splash screen is
1897 loaded very quickly after power-on.
1899 CONFIG_SPLASHIMAGE_GUARD
1901 If this option is set, then U-Boot will prevent the environment
1902 variable "splashimage" from being set to a problematic address
1903 (see doc/README.displaying-bmps).
1904 This option is useful for targets where, due to alignment
1905 restrictions, an improperly aligned BMP image will cause a data
1906 abort. If you think you will not have problems with unaligned
1907 accesses (for example because your toolchain prevents them)
1908 there is no need to set this option.
1910 CONFIG_SPLASH_SCREEN_ALIGN
1912 If this option is set the splash image can be freely positioned
1913 on the screen. Environment variable "splashpos" specifies the
1914 position as "x,y". If a positive number is given it is used as
1915 number of pixel from left/top. If a negative number is given it
1916 is used as number of pixel from right/bottom. You can also
1917 specify 'm' for centering the image.
1920 setenv splashpos m,m
1921 => image at center of screen
1923 setenv splashpos 30,20
1924 => image at x = 30 and y = 20
1926 setenv splashpos -10,m
1927 => vertically centered image
1928 at x = dspWidth - bmpWidth - 9
1930 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1932 If this option is set, additionally to standard BMP
1933 images, gzipped BMP images can be displayed via the
1934 splashscreen support or the bmp command.
1936 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1938 If this option is set, 8-bit RLE compressed BMP images
1939 can be displayed via the splashscreen support or the
1942 - Do compressing for memory range:
1945 If this option is set, it would use zlib deflate method
1946 to compress the specified memory at its best effort.
1948 - Compression support:
1951 Enabled by default to support gzip compressed images.
1955 If this option is set, support for bzip2 compressed
1956 images is included. If not, only uncompressed and gzip
1957 compressed images are supported.
1959 NOTE: the bzip2 algorithm requires a lot of RAM, so
1960 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1965 If this option is set, support for lzma compressed
1968 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1969 requires an amount of dynamic memory that is given by the
1972 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1974 Where lc and lp stand for, respectively, Literal context bits
1975 and Literal pos bits.
1977 This value is upper-bounded by 14MB in the worst case. Anyway,
1978 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1979 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1980 a very small buffer.
1982 Use the lzmainfo tool to determinate the lc and lp values and
1983 then calculate the amount of needed dynamic memory (ensuring
1984 the appropriate CONFIG_SYS_MALLOC_LEN value).
1988 If this option is set, support for LZO compressed images
1994 The address of PHY on MII bus.
1996 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1998 The clock frequency of the MII bus
2002 If this option is set, support for speed/duplex
2003 detection of gigabit PHY is included.
2005 CONFIG_PHY_RESET_DELAY
2007 Some PHY like Intel LXT971A need extra delay after
2008 reset before any MII register access is possible.
2009 For such PHY, set this option to the usec delay
2010 required. (minimum 300usec for LXT971A)
2012 CONFIG_PHY_CMD_DELAY (ppc4xx)
2014 Some PHY like Intel LXT971A need extra delay after
2015 command issued before MII status register can be read
2020 Define a default value for the IP address to use for
2021 the default Ethernet interface, in case this is not
2022 determined through e.g. bootp.
2023 (Environment variable "ipaddr")
2025 - Server IP address:
2028 Defines a default value for the IP address of a TFTP
2029 server to contact when using the "tftboot" command.
2030 (Environment variable "serverip")
2032 CONFIG_KEEP_SERVERADDR
2034 Keeps the server's MAC address, in the env 'serveraddr'
2035 for passing to bootargs (like Linux's netconsole option)
2037 - Gateway IP address:
2040 Defines a default value for the IP address of the
2041 default router where packets to other networks are
2043 (Environment variable "gatewayip")
2048 Defines a default value for the subnet mask (or
2049 routing prefix) which is used to determine if an IP
2050 address belongs to the local subnet or needs to be
2051 forwarded through a router.
2052 (Environment variable "netmask")
2054 - Multicast TFTP Mode:
2057 Defines whether you want to support multicast TFTP as per
2058 rfc-2090; for example to work with atftp. Lets lots of targets
2059 tftp down the same boot image concurrently. Note: the Ethernet
2060 driver in use must provide a function: mcast() to join/leave a
2063 - BOOTP Recovery Mode:
2064 CONFIG_BOOTP_RANDOM_DELAY
2066 If you have many targets in a network that try to
2067 boot using BOOTP, you may want to avoid that all
2068 systems send out BOOTP requests at precisely the same
2069 moment (which would happen for instance at recovery
2070 from a power failure, when all systems will try to
2071 boot, thus flooding the BOOTP server. Defining
2072 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
2073 inserted before sending out BOOTP requests. The
2074 following delays are inserted then:
2076 1st BOOTP request: delay 0 ... 1 sec
2077 2nd BOOTP request: delay 0 ... 2 sec
2078 3rd BOOTP request: delay 0 ... 4 sec
2080 BOOTP requests: delay 0 ... 8 sec
2082 CONFIG_BOOTP_ID_CACHE_SIZE
2084 BOOTP packets are uniquely identified using a 32-bit ID. The
2085 server will copy the ID from client requests to responses and
2086 U-Boot will use this to determine if it is the destination of
2087 an incoming response. Some servers will check that addresses
2088 aren't in use before handing them out (usually using an ARP
2089 ping) and therefore take up to a few hundred milliseconds to
2090 respond. Network congestion may also influence the time it
2091 takes for a response to make it back to the client. If that
2092 time is too long, U-Boot will retransmit requests. In order
2093 to allow earlier responses to still be accepted after these
2094 retransmissions, U-Boot's BOOTP client keeps a small cache of
2095 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
2096 cache. The default is to keep IDs for up to four outstanding
2097 requests. Increasing this will allow U-Boot to accept offers
2098 from a BOOTP client in networks with unusually high latency.
2100 - DHCP Advanced Options:
2101 You can fine tune the DHCP functionality by defining
2102 CONFIG_BOOTP_* symbols:
2104 CONFIG_BOOTP_SUBNETMASK
2105 CONFIG_BOOTP_GATEWAY
2106 CONFIG_BOOTP_HOSTNAME
2107 CONFIG_BOOTP_NISDOMAIN
2108 CONFIG_BOOTP_BOOTPATH
2109 CONFIG_BOOTP_BOOTFILESIZE
2112 CONFIG_BOOTP_SEND_HOSTNAME
2113 CONFIG_BOOTP_NTPSERVER
2114 CONFIG_BOOTP_TIMEOFFSET
2115 CONFIG_BOOTP_VENDOREX
2116 CONFIG_BOOTP_MAY_FAIL
2118 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
2119 environment variable, not the BOOTP server.
2121 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
2122 after the configured retry count, the call will fail
2123 instead of starting over. This can be used to fail over
2124 to Link-local IP address configuration if the DHCP server
2127 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
2128 serverip from a DHCP server, it is possible that more
2129 than one DNS serverip is offered to the client.
2130 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
2131 serverip will be stored in the additional environment
2132 variable "dnsip2". The first DNS serverip is always
2133 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
2136 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2137 to do a dynamic update of a DNS server. To do this, they
2138 need the hostname of the DHCP requester.
2139 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2140 of the "hostname" environment variable is passed as
2141 option 12 to the DHCP server.
2143 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2145 A 32bit value in microseconds for a delay between
2146 receiving a "DHCP Offer" and sending the "DHCP Request".
2147 This fixes a problem with certain DHCP servers that don't
2148 respond 100% of the time to a "DHCP request". E.g. On an
2149 AT91RM9200 processor running at 180MHz, this delay needed
2150 to be *at least* 15,000 usec before a Windows Server 2003
2151 DHCP server would reply 100% of the time. I recommend at
2152 least 50,000 usec to be safe. The alternative is to hope
2153 that one of the retries will be successful but note that
2154 the DHCP timeout and retry process takes a longer than
2157 - Link-local IP address negotiation:
2158 Negotiate with other link-local clients on the local network
2159 for an address that doesn't require explicit configuration.
2160 This is especially useful if a DHCP server cannot be guaranteed
2161 to exist in all environments that the device must operate.
2163 See doc/README.link-local for more information.
2166 CONFIG_CDP_DEVICE_ID
2168 The device id used in CDP trigger frames.
2170 CONFIG_CDP_DEVICE_ID_PREFIX
2172 A two character string which is prefixed to the MAC address
2177 A printf format string which contains the ascii name of
2178 the port. Normally is set to "eth%d" which sets
2179 eth0 for the first Ethernet, eth1 for the second etc.
2181 CONFIG_CDP_CAPABILITIES
2183 A 32bit integer which indicates the device capabilities;
2184 0x00000010 for a normal host which does not forwards.
2188 An ascii string containing the version of the software.
2192 An ascii string containing the name of the platform.
2196 A 32bit integer sent on the trigger.
2198 CONFIG_CDP_POWER_CONSUMPTION
2200 A 16bit integer containing the power consumption of the
2201 device in .1 of milliwatts.
2203 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2205 A byte containing the id of the VLAN.
2207 - Status LED: CONFIG_STATUS_LED
2209 Several configurations allow to display the current
2210 status using a LED. For instance, the LED will blink
2211 fast while running U-Boot code, stop blinking as
2212 soon as a reply to a BOOTP request was received, and
2213 start blinking slow once the Linux kernel is running
2214 (supported by a status LED driver in the Linux
2215 kernel). Defining CONFIG_STATUS_LED enables this
2221 The status LED can be connected to a GPIO pin.
2222 In such cases, the gpio_led driver can be used as a
2223 status LED backend implementation. Define CONFIG_GPIO_LED
2224 to include the gpio_led driver in the U-Boot binary.
2226 CONFIG_GPIO_LED_INVERTED_TABLE
2227 Some GPIO connected LEDs may have inverted polarity in which
2228 case the GPIO high value corresponds to LED off state and
2229 GPIO low value corresponds to LED on state.
2230 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2231 with a list of GPIO LEDs that have inverted polarity.
2233 - CAN Support: CONFIG_CAN_DRIVER
2235 Defining CONFIG_CAN_DRIVER enables CAN driver support
2236 on those systems that support this (optional)
2237 feature, like the TQM8xxL modules.
2239 - I2C Support: CONFIG_SYS_I2C
2241 This enable the NEW i2c subsystem, and will allow you to use
2242 i2c commands at the u-boot command line (as long as you set
2243 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2244 based realtime clock chips or other i2c devices. See
2245 common/cmd_i2c.c for a description of the command line
2248 ported i2c driver to the new framework:
2249 - drivers/i2c/soft_i2c.c:
2250 - activate first bus with CONFIG_SYS_I2C_SOFT define
2251 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2252 for defining speed and slave address
2253 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2254 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2255 for defining speed and slave address
2256 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2257 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2258 for defining speed and slave address
2259 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2260 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2261 for defining speed and slave address
2263 - drivers/i2c/fsl_i2c.c:
2264 - activate i2c driver with CONFIG_SYS_I2C_FSL
2265 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2266 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2267 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2269 - If your board supports a second fsl i2c bus, define
2270 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2271 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2272 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2275 - drivers/i2c/tegra_i2c.c:
2276 - activate this driver with CONFIG_SYS_I2C_TEGRA
2277 - This driver adds 4 i2c buses with a fix speed from
2278 100000 and the slave addr 0!
2280 - drivers/i2c/ppc4xx_i2c.c
2281 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2282 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2283 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2285 - drivers/i2c/i2c_mxc.c
2286 - activate this driver with CONFIG_SYS_I2C_MXC
2287 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
2288 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
2289 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
2290 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
2291 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2292 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2293 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2294 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2295 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2296 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2297 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
2298 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
2299 If those defines are not set, default value is 100000
2300 for speed, and 0 for slave.
2302 - drivers/i2c/rcar_i2c.c:
2303 - activate this driver with CONFIG_SYS_I2C_RCAR
2304 - This driver adds 4 i2c buses
2306 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2307 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2308 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2309 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2310 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2311 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2312 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2313 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2314 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2316 - drivers/i2c/sh_i2c.c:
2317 - activate this driver with CONFIG_SYS_I2C_SH
2318 - This driver adds from 2 to 5 i2c buses
2320 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2321 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2322 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2323 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2324 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2325 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2326 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2327 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2328 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2329 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2330 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2331 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2332 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
2334 - drivers/i2c/omap24xx_i2c.c
2335 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2336 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2337 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2338 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2339 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2340 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2341 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2342 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2343 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2344 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2345 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2347 - drivers/i2c/zynq_i2c.c
2348 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2349 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2350 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2352 - drivers/i2c/s3c24x0_i2c.c:
2353 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2354 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2355 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2356 with a fix speed from 100000 and the slave addr 0!
2358 - drivers/i2c/ihs_i2c.c
2359 - activate this driver with CONFIG_SYS_I2C_IHS
2360 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
2361 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
2362 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
2363 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
2364 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
2365 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
2366 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
2367 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
2368 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
2369 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
2370 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
2371 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
2372 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
2373 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
2374 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
2375 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
2376 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
2377 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
2378 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
2379 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
2380 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
2384 CONFIG_SYS_NUM_I2C_BUSES
2385 Hold the number of i2c buses you want to use. If you
2386 don't use/have i2c muxes on your i2c bus, this
2387 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2390 CONFIG_SYS_I2C_DIRECT_BUS
2391 define this, if you don't use i2c muxes on your hardware.
2392 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2395 CONFIG_SYS_I2C_MAX_HOPS
2396 define how many muxes are maximal consecutively connected
2397 on one i2c bus. If you not use i2c muxes, omit this
2400 CONFIG_SYS_I2C_BUSES
2401 hold a list of buses you want to use, only used if
2402 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2403 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2404 CONFIG_SYS_NUM_I2C_BUSES = 9:
2406 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2407 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2408 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2409 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2410 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2411 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2412 {1, {I2C_NULL_HOP}}, \
2413 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2414 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2418 bus 0 on adapter 0 without a mux
2419 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2420 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2421 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2422 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2423 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2424 bus 6 on adapter 1 without a mux
2425 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2426 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2428 If you do not have i2c muxes on your board, omit this define.
2430 - Legacy I2C Support: CONFIG_HARD_I2C
2432 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2433 provides the following compelling advantages:
2435 - more than one i2c adapter is usable
2436 - approved multibus support
2437 - better i2c mux support
2439 ** Please consider updating your I2C driver now. **
2441 These enable legacy I2C serial bus commands. Defining
2442 CONFIG_HARD_I2C will include the appropriate I2C driver
2443 for the selected CPU.
2445 This will allow you to use i2c commands at the u-boot
2446 command line (as long as you set CONFIG_CMD_I2C in
2447 CONFIG_COMMANDS) and communicate with i2c based realtime
2448 clock chips. See common/cmd_i2c.c for a description of the
2449 command line interface.
2451 CONFIG_HARD_I2C selects a hardware I2C controller.
2453 There are several other quantities that must also be
2454 defined when you define CONFIG_HARD_I2C.
2456 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2457 to be the frequency (in Hz) at which you wish your i2c bus
2458 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2459 the CPU's i2c node address).
2461 Now, the u-boot i2c code for the mpc8xx
2462 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2463 and so its address should therefore be cleared to 0 (See,
2464 eg, MPC823e User's Manual p.16-473). So, set
2465 CONFIG_SYS_I2C_SLAVE to 0.
2467 CONFIG_SYS_I2C_INIT_MPC5XXX
2469 When a board is reset during an i2c bus transfer
2470 chips might think that the current transfer is still
2471 in progress. Reset the slave devices by sending start
2472 commands until the slave device responds.
2474 That's all that's required for CONFIG_HARD_I2C.
2476 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2477 then the following macros need to be defined (examples are
2478 from include/configs/lwmon.h):
2482 (Optional). Any commands necessary to enable the I2C
2483 controller or configure ports.
2485 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2489 (Only for MPC8260 CPU). The I/O port to use (the code
2490 assumes both bits are on the same port). Valid values
2491 are 0..3 for ports A..D.
2495 The code necessary to make the I2C data line active
2496 (driven). If the data line is open collector, this
2499 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2503 The code necessary to make the I2C data line tri-stated
2504 (inactive). If the data line is open collector, this
2507 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2511 Code that returns true if the I2C data line is high,
2514 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2518 If <bit> is true, sets the I2C data line high. If it
2519 is false, it clears it (low).
2521 eg: #define I2C_SDA(bit) \
2522 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2523 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2527 If <bit> is true, sets the I2C clock line high. If it
2528 is false, it clears it (low).
2530 eg: #define I2C_SCL(bit) \
2531 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2532 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2536 This delay is invoked four times per clock cycle so this
2537 controls the rate of data transfer. The data rate thus
2538 is 1 / (I2C_DELAY * 4). Often defined to be something
2541 #define I2C_DELAY udelay(2)
2543 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2545 If your arch supports the generic GPIO framework (asm/gpio.h),
2546 then you may alternatively define the two GPIOs that are to be
2547 used as SCL / SDA. Any of the previous I2C_xxx macros will
2548 have GPIO-based defaults assigned to them as appropriate.
2550 You should define these to the GPIO value as given directly to
2551 the generic GPIO functions.
2553 CONFIG_SYS_I2C_INIT_BOARD
2555 When a board is reset during an i2c bus transfer
2556 chips might think that the current transfer is still
2557 in progress. On some boards it is possible to access
2558 the i2c SCLK line directly, either by using the
2559 processor pin as a GPIO or by having a second pin
2560 connected to the bus. If this option is defined a
2561 custom i2c_init_board() routine in boards/xxx/board.c
2562 is run early in the boot sequence.
2564 CONFIG_SYS_I2C_BOARD_LATE_INIT
2566 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2567 defined a custom i2c_board_late_init() routine in
2568 boards/xxx/board.c is run AFTER the operations in i2c_init()
2569 is completed. This callpoint can be used to unreset i2c bus
2570 using CPU i2c controller register accesses for CPUs whose i2c
2571 controller provide such a method. It is called at the end of
2572 i2c_init() to allow i2c_init operations to setup the i2c bus
2573 controller on the CPU (e.g. setting bus speed & slave address).
2575 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2577 This option enables configuration of bi_iic_fast[] flags
2578 in u-boot bd_info structure based on u-boot environment
2579 variable "i2cfast". (see also i2cfast)
2581 CONFIG_I2C_MULTI_BUS
2583 This option allows the use of multiple I2C buses, each of which
2584 must have a controller. At any point in time, only one bus is
2585 active. To switch to a different bus, use the 'i2c dev' command.
2586 Note that bus numbering is zero-based.
2588 CONFIG_SYS_I2C_NOPROBES
2590 This option specifies a list of I2C devices that will be skipped
2591 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2592 is set, specify a list of bus-device pairs. Otherwise, specify
2593 a 1D array of device addresses
2596 #undef CONFIG_I2C_MULTI_BUS
2597 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2599 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2601 #define CONFIG_I2C_MULTI_BUS
2602 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2604 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2606 CONFIG_SYS_SPD_BUS_NUM
2608 If defined, then this indicates the I2C bus number for DDR SPD.
2609 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2611 CONFIG_SYS_RTC_BUS_NUM
2613 If defined, then this indicates the I2C bus number for the RTC.
2614 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2616 CONFIG_SYS_DTT_BUS_NUM
2618 If defined, then this indicates the I2C bus number for the DTT.
2619 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2621 CONFIG_SYS_I2C_DTT_ADDR:
2623 If defined, specifies the I2C address of the DTT device.
2624 If not defined, then U-Boot uses predefined value for
2625 specified DTT device.
2627 CONFIG_SOFT_I2C_READ_REPEATED_START
2629 defining this will force the i2c_read() function in
2630 the soft_i2c driver to perform an I2C repeated start
2631 between writing the address pointer and reading the
2632 data. If this define is omitted the default behaviour
2633 of doing a stop-start sequence will be used. Most I2C
2634 devices can use either method, but some require one or
2637 - SPI Support: CONFIG_SPI
2639 Enables SPI driver (so far only tested with
2640 SPI EEPROM, also an instance works with Crystal A/D and
2641 D/As on the SACSng board)
2645 Enables the driver for SPI controller on SuperH. Currently
2646 only SH7757 is supported.
2650 Enables a software (bit-bang) SPI driver rather than
2651 using hardware support. This is a general purpose
2652 driver that only requires three general I/O port pins
2653 (two outputs, one input) to function. If this is
2654 defined, the board configuration must define several
2655 SPI configuration items (port pins to use, etc). For
2656 an example, see include/configs/sacsng.h.
2660 Enables a hardware SPI driver for general-purpose reads
2661 and writes. As with CONFIG_SOFT_SPI, the board configuration
2662 must define a list of chip-select function pointers.
2663 Currently supported on some MPC8xxx processors. For an
2664 example, see include/configs/mpc8349emds.h.
2668 Enables the driver for the SPI controllers on i.MX and MXC
2669 SoCs. Currently i.MX31/35/51 are supported.
2671 CONFIG_SYS_SPI_MXC_WAIT
2672 Timeout for waiting until spi transfer completed.
2673 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2675 - FPGA Support: CONFIG_FPGA
2677 Enables FPGA subsystem.
2679 CONFIG_FPGA_<vendor>
2681 Enables support for specific chip vendors.
2684 CONFIG_FPGA_<family>
2686 Enables support for FPGA family.
2687 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2691 Specify the number of FPGA devices to support.
2693 CONFIG_CMD_FPGA_LOADMK
2695 Enable support for fpga loadmk command
2697 CONFIG_CMD_FPGA_LOADP
2699 Enable support for fpga loadp command - load partial bitstream
2701 CONFIG_CMD_FPGA_LOADBP
2703 Enable support for fpga loadbp command - load partial bitstream
2706 CONFIG_SYS_FPGA_PROG_FEEDBACK
2708 Enable printing of hash marks during FPGA configuration.
2710 CONFIG_SYS_FPGA_CHECK_BUSY
2712 Enable checks on FPGA configuration interface busy
2713 status by the configuration function. This option
2714 will require a board or device specific function to
2719 If defined, a function that provides delays in the FPGA
2720 configuration driver.
2722 CONFIG_SYS_FPGA_CHECK_CTRLC
2723 Allow Control-C to interrupt FPGA configuration
2725 CONFIG_SYS_FPGA_CHECK_ERROR
2727 Check for configuration errors during FPGA bitfile
2728 loading. For example, abort during Virtex II
2729 configuration if the INIT_B line goes low (which
2730 indicated a CRC error).
2732 CONFIG_SYS_FPGA_WAIT_INIT
2734 Maximum time to wait for the INIT_B line to de-assert
2735 after PROB_B has been de-asserted during a Virtex II
2736 FPGA configuration sequence. The default time is 500
2739 CONFIG_SYS_FPGA_WAIT_BUSY
2741 Maximum time to wait for BUSY to de-assert during
2742 Virtex II FPGA configuration. The default is 5 ms.
2744 CONFIG_SYS_FPGA_WAIT_CONFIG
2746 Time to wait after FPGA configuration. The default is
2749 - Configuration Management:
2752 Some SoCs need special image types (e.g. U-Boot binary
2753 with a special header) as build targets. By defining
2754 CONFIG_BUILD_TARGET in the SoC / board header, this
2755 special image will be automatically built upon calling
2760 If defined, this string will be added to the U-Boot
2761 version information (U_BOOT_VERSION)
2763 - Vendor Parameter Protection:
2765 U-Boot considers the values of the environment
2766 variables "serial#" (Board Serial Number) and
2767 "ethaddr" (Ethernet Address) to be parameters that
2768 are set once by the board vendor / manufacturer, and
2769 protects these variables from casual modification by
2770 the user. Once set, these variables are read-only,
2771 and write or delete attempts are rejected. You can
2772 change this behaviour:
2774 If CONFIG_ENV_OVERWRITE is #defined in your config
2775 file, the write protection for vendor parameters is
2776 completely disabled. Anybody can change or delete
2779 Alternatively, if you define _both_ an ethaddr in the
2780 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2781 Ethernet address is installed in the environment,
2782 which can be changed exactly ONCE by the user. [The
2783 serial# is unaffected by this, i. e. it remains
2786 The same can be accomplished in a more flexible way
2787 for any variable by configuring the type of access
2788 to allow for those variables in the ".flags" variable
2789 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2794 Define this variable to enable the reservation of
2795 "protected RAM", i. e. RAM which is not overwritten
2796 by U-Boot. Define CONFIG_PRAM to hold the number of
2797 kB you want to reserve for pRAM. You can overwrite
2798 this default value by defining an environment
2799 variable "pram" to the number of kB you want to
2800 reserve. Note that the board info structure will
2801 still show the full amount of RAM. If pRAM is
2802 reserved, a new environment variable "mem" will
2803 automatically be defined to hold the amount of
2804 remaining RAM in a form that can be passed as boot
2805 argument to Linux, for instance like that:
2807 setenv bootargs ... mem=\${mem}
2810 This way you can tell Linux not to use this memory,
2811 either, which results in a memory region that will
2812 not be affected by reboots.
2814 *WARNING* If your board configuration uses automatic
2815 detection of the RAM size, you must make sure that
2816 this memory test is non-destructive. So far, the
2817 following board configurations are known to be
2820 IVMS8, IVML24, SPD8xx, TQM8xxL,
2821 HERMES, IP860, RPXlite, LWMON,
2824 - Access to physical memory region (> 4GB)
2825 Some basic support is provided for operations on memory not
2826 normally accessible to U-Boot - e.g. some architectures
2827 support access to more than 4GB of memory on 32-bit
2828 machines using physical address extension or similar.
2829 Define CONFIG_PHYSMEM to access this basic support, which
2830 currently only supports clearing the memory.
2835 Define this variable to stop the system in case of a
2836 fatal error, so that you have to reset it manually.
2837 This is probably NOT a good idea for an embedded
2838 system where you want the system to reboot
2839 automatically as fast as possible, but it may be
2840 useful during development since you can try to debug
2841 the conditions that lead to the situation.
2843 CONFIG_NET_RETRY_COUNT
2845 This variable defines the number of retries for
2846 network operations like ARP, RARP, TFTP, or BOOTP
2847 before giving up the operation. If not defined, a
2848 default value of 5 is used.
2852 Timeout waiting for an ARP reply in milliseconds.
2856 Timeout in milliseconds used in NFS protocol.
2857 If you encounter "ERROR: Cannot umount" in nfs command,
2858 try longer timeout such as
2859 #define CONFIG_NFS_TIMEOUT 10000UL
2861 - Command Interpreter:
2862 CONFIG_AUTO_COMPLETE
2864 Enable auto completion of commands using TAB.
2866 CONFIG_SYS_PROMPT_HUSH_PS2
2868 This defines the secondary prompt string, which is
2869 printed when the command interpreter needs more input
2870 to complete a command. Usually "> ".
2874 In the current implementation, the local variables
2875 space and global environment variables space are
2876 separated. Local variables are those you define by
2877 simply typing `name=value'. To access a local
2878 variable later on, you have write `$name' or
2879 `${name}'; to execute the contents of a variable
2880 directly type `$name' at the command prompt.
2882 Global environment variables are those you use
2883 setenv/printenv to work with. To run a command stored
2884 in such a variable, you need to use the run command,
2885 and you must not use the '$' sign to access them.
2887 To store commands and special characters in a
2888 variable, please use double quotation marks
2889 surrounding the whole text of the variable, instead
2890 of the backslashes before semicolons and special
2893 - Command Line Editing and History:
2894 CONFIG_CMDLINE_EDITING
2896 Enable editing and History functions for interactive
2897 command line input operations
2899 - Command Line PS1/PS2 support:
2900 CONFIG_CMDLINE_PS_SUPPORT
2902 Enable support for changing the command prompt string
2903 at run-time. Only static string is supported so far.
2904 The string is obtained from environment variables PS1
2907 - Default Environment:
2908 CONFIG_EXTRA_ENV_SETTINGS
2910 Define this to contain any number of null terminated
2911 strings (variable = value pairs) that will be part of
2912 the default environment compiled into the boot image.
2914 For example, place something like this in your
2915 board's config file:
2917 #define CONFIG_EXTRA_ENV_SETTINGS \
2921 Warning: This method is based on knowledge about the
2922 internal format how the environment is stored by the
2923 U-Boot code. This is NOT an official, exported
2924 interface! Although it is unlikely that this format
2925 will change soon, there is no guarantee either.
2926 You better know what you are doing here.
2928 Note: overly (ab)use of the default environment is
2929 discouraged. Make sure to check other ways to preset
2930 the environment like the "source" command or the
2933 CONFIG_ENV_VARS_UBOOT_CONFIG
2935 Define this in order to add variables describing the
2936 U-Boot build configuration to the default environment.
2937 These will be named arch, cpu, board, vendor, and soc.
2939 Enabling this option will cause the following to be defined:
2947 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2949 Define this in order to add variables describing certain
2950 run-time determined information about the hardware to the
2951 environment. These will be named board_name, board_rev.
2953 CONFIG_DELAY_ENVIRONMENT
2955 Normally the environment is loaded when the board is
2956 initialised so that it is available to U-Boot. This inhibits
2957 that so that the environment is not available until
2958 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2959 this is instead controlled by the value of
2960 /config/load-environment.
2962 - Parallel Flash support:
2965 Traditionally U-Boot was run on systems with parallel NOR
2966 flash. This option is used to disable support for parallel NOR
2967 flash. This option should be defined if the board does not have
2970 If this option is not defined one of the generic flash drivers
2971 (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be
2972 selected or the board must provide an implementation of the
2973 flash API (see include/flash.h).
2975 - DataFlash Support:
2976 CONFIG_HAS_DATAFLASH
2978 Defining this option enables DataFlash features and
2979 allows to read/write in Dataflash via the standard
2982 - Serial Flash support
2985 Defining this option enables SPI flash commands
2986 'sf probe/read/write/erase/update'.
2988 Usage requires an initial 'probe' to define the serial
2989 flash parameters, followed by read/write/erase/update
2992 The following defaults may be provided by the platform
2993 to handle the common case when only a single serial
2994 flash is present on the system.
2996 CONFIG_SF_DEFAULT_BUS Bus identifier
2997 CONFIG_SF_DEFAULT_CS Chip-select
2998 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2999 CONFIG_SF_DEFAULT_SPEED in Hz
3003 Define this option to include a destructive SPI flash
3006 CONFIG_SF_DUAL_FLASH Dual flash memories
3008 Define this option to use dual flash support where two flash
3009 memories can be connected with a given cs line.
3010 Currently Xilinx Zynq qspi supports these type of connections.
3012 - SystemACE Support:
3015 Adding this option adds support for Xilinx SystemACE
3016 chips attached via some sort of local bus. The address
3017 of the chip must also be defined in the
3018 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
3020 #define CONFIG_SYSTEMACE
3021 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
3023 When SystemACE support is added, the "ace" device type
3024 becomes available to the fat commands, i.e. fatls.
3026 - TFTP Fixed UDP Port:
3029 If this is defined, the environment variable tftpsrcp
3030 is used to supply the TFTP UDP source port value.
3031 If tftpsrcp isn't defined, the normal pseudo-random port
3032 number generator is used.
3034 Also, the environment variable tftpdstp is used to supply
3035 the TFTP UDP destination port value. If tftpdstp isn't
3036 defined, the normal port 69 is used.
3038 The purpose for tftpsrcp is to allow a TFTP server to
3039 blindly start the TFTP transfer using the pre-configured
3040 target IP address and UDP port. This has the effect of
3041 "punching through" the (Windows XP) firewall, allowing
3042 the remainder of the TFTP transfer to proceed normally.
3043 A better solution is to properly configure the firewall,
3044 but sometimes that is not allowed.
3049 This enables a generic 'hash' command which can produce
3050 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
3054 Enable the hash verify command (hash -v). This adds to code
3057 CONFIG_SHA1 - This option enables support of hashing using SHA1
3058 algorithm. The hash is calculated in software.
3059 CONFIG_SHA256 - This option enables support of hashing using
3060 SHA256 algorithm. The hash is calculated in software.
3061 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration
3062 for SHA1/SHA256 hashing.
3063 This affects the 'hash' command and also the
3064 hash_lookup_algo() function.
3065 CONFIG_SHA_PROG_HW_ACCEL - This option enables
3066 hardware-acceleration for SHA1/SHA256 progressive hashing.
3067 Data can be streamed in a block at a time and the hashing
3068 is performed in hardware.
3070 Note: There is also a sha1sum command, which should perhaps
3071 be deprecated in favour of 'hash sha1'.
3073 - Freescale i.MX specific commands:
3074 CONFIG_CMD_HDMIDETECT
3075 This enables 'hdmidet' command which returns true if an
3076 HDMI monitor is detected. This command is i.MX 6 specific.
3079 This enables the 'bmode' (bootmode) command for forcing
3080 a boot from specific media.
3082 This is useful for forcing the ROM's usb downloader to
3083 activate upon a watchdog reset which is nice when iterating
3084 on U-Boot. Using the reset button or running bmode normal
3085 will set it back to normal. This command currently
3086 supports i.MX53 and i.MX6.
3088 - bootcount support:
3089 CONFIG_BOOTCOUNT_LIMIT
3091 This enables the bootcounter support, see:
3092 http://www.denx.de/wiki/DULG/UBootBootCountLimit
3095 enable special bootcounter support on at91sam9xe based boards.
3097 enable special bootcounter support on blackfin based boards.
3099 enable special bootcounter support on da850 based boards.
3100 CONFIG_BOOTCOUNT_RAM
3101 enable support for the bootcounter in RAM
3102 CONFIG_BOOTCOUNT_I2C
3103 enable support for the bootcounter on an i2c (like RTC) device.
3104 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
3105 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
3107 CONFIG_BOOTCOUNT_ALEN = address len
3109 - Show boot progress:
3110 CONFIG_SHOW_BOOT_PROGRESS
3112 Defining this option allows to add some board-
3113 specific code (calling a user-provided function
3114 "show_boot_progress(int)") that enables you to show
3115 the system's boot progress on some display (for
3116 example, some LED's) on your board. At the moment,
3117 the following checkpoints are implemented:
3120 Legacy uImage format:
3123 1 common/cmd_bootm.c before attempting to boot an image
3124 -1 common/cmd_bootm.c Image header has bad magic number
3125 2 common/cmd_bootm.c Image header has correct magic number
3126 -2 common/cmd_bootm.c Image header has bad checksum
3127 3 common/cmd_bootm.c Image header has correct checksum
3128 -3 common/cmd_bootm.c Image data has bad checksum
3129 4 common/cmd_bootm.c Image data has correct checksum
3130 -4 common/cmd_bootm.c Image is for unsupported architecture
3131 5 common/cmd_bootm.c Architecture check OK
3132 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
3133 6 common/cmd_bootm.c Image Type check OK
3134 -6 common/cmd_bootm.c gunzip uncompression error
3135 -7 common/cmd_bootm.c Unimplemented compression type
3136 7 common/cmd_bootm.c Uncompression OK
3137 8 common/cmd_bootm.c No uncompress/copy overwrite error
3138 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3140 9 common/image.c Start initial ramdisk verification
3141 -10 common/image.c Ramdisk header has bad magic number
3142 -11 common/image.c Ramdisk header has bad checksum
3143 10 common/image.c Ramdisk header is OK
3144 -12 common/image.c Ramdisk data has bad checksum
3145 11 common/image.c Ramdisk data has correct checksum
3146 12 common/image.c Ramdisk verification complete, start loading
3147 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3148 13 common/image.c Start multifile image verification
3149 14 common/image.c No initial ramdisk, no multifile, continue.
3151 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3153 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3154 -31 post/post.c POST test failed, detected by post_output_backlog()
3155 -32 post/post.c POST test failed, detected by post_run_single()
3157 34 common/cmd_doc.c before loading a Image from a DOC device
3158 -35 common/cmd_doc.c Bad usage of "doc" command
3159 35 common/cmd_doc.c correct usage of "doc" command
3160 -36 common/cmd_doc.c No boot device
3161 36 common/cmd_doc.c correct boot device
3162 -37 common/cmd_doc.c Unknown Chip ID on boot device
3163 37 common/cmd_doc.c correct chip ID found, device available
3164 -38 common/cmd_doc.c Read Error on boot device
3165 38 common/cmd_doc.c reading Image header from DOC device OK
3166 -39 common/cmd_doc.c Image header has bad magic number
3167 39 common/cmd_doc.c Image header has correct magic number
3168 -40 common/cmd_doc.c Error reading Image from DOC device
3169 40 common/cmd_doc.c Image header has correct magic number
3170 41 common/cmd_ide.c before loading a Image from a IDE device
3171 -42 common/cmd_ide.c Bad usage of "ide" command
3172 42 common/cmd_ide.c correct usage of "ide" command
3173 -43 common/cmd_ide.c No boot device
3174 43 common/cmd_ide.c boot device found
3175 -44 common/cmd_ide.c Device not available
3176 44 common/cmd_ide.c Device available
3177 -45 common/cmd_ide.c wrong partition selected
3178 45 common/cmd_ide.c partition selected
3179 -46 common/cmd_ide.c Unknown partition table
3180 46 common/cmd_ide.c valid partition table found
3181 -47 common/cmd_ide.c Invalid partition type
3182 47 common/cmd_ide.c correct partition type
3183 -48 common/cmd_ide.c Error reading Image Header on boot device
3184 48 common/cmd_ide.c reading Image Header from IDE device OK
3185 -49 common/cmd_ide.c Image header has bad magic number
3186 49 common/cmd_ide.c Image header has correct magic number
3187 -50 common/cmd_ide.c Image header has bad checksum
3188 50 common/cmd_ide.c Image header has correct checksum
3189 -51 common/cmd_ide.c Error reading Image from IDE device
3190 51 common/cmd_ide.c reading Image from IDE device OK
3191 52 common/cmd_nand.c before loading a Image from a NAND device
3192 -53 common/cmd_nand.c Bad usage of "nand" command
3193 53 common/cmd_nand.c correct usage of "nand" command
3194 -54 common/cmd_nand.c No boot device
3195 54 common/cmd_nand.c boot device found
3196 -55 common/cmd_nand.c Unknown Chip ID on boot device
3197 55 common/cmd_nand.c correct chip ID found, device available
3198 -56 common/cmd_nand.c Error reading Image Header on boot device
3199 56 common/cmd_nand.c reading Image Header from NAND device OK
3200 -57 common/cmd_nand.c Image header has bad magic number
3201 57 common/cmd_nand.c Image header has correct magic number
3202 -58 common/cmd_nand.c Error reading Image from NAND device
3203 58 common/cmd_nand.c reading Image from NAND device OK
3205 -60 common/env_common.c Environment has a bad CRC, using default
3207 64 net/eth.c starting with Ethernet configuration.
3208 -64 net/eth.c no Ethernet found.
3209 65 net/eth.c Ethernet found.
3211 -80 common/cmd_net.c usage wrong
3212 80 common/cmd_net.c before calling net_loop()
3213 -81 common/cmd_net.c some error in net_loop() occurred
3214 81 common/cmd_net.c net_loop() back without error
3215 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3216 82 common/cmd_net.c trying automatic boot
3217 83 common/cmd_net.c running "source" command
3218 -83 common/cmd_net.c some error in automatic boot or "source" command
3219 84 common/cmd_net.c end without errors
3224 100 common/cmd_bootm.c Kernel FIT Image has correct format
3225 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3226 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3227 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3228 102 common/cmd_bootm.c Kernel unit name specified
3229 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3230 103 common/cmd_bootm.c Found configuration node
3231 104 common/cmd_bootm.c Got kernel subimage node offset
3232 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3233 105 common/cmd_bootm.c Kernel subimage hash verification OK
3234 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3235 106 common/cmd_bootm.c Architecture check OK
3236 -106 common/cmd_bootm.c Kernel subimage has wrong type
3237 107 common/cmd_bootm.c Kernel subimage type OK
3238 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3239 108 common/cmd_bootm.c Got kernel subimage data/size
3240 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3241 -109 common/cmd_bootm.c Can't get kernel subimage type
3242 -110 common/cmd_bootm.c Can't get kernel subimage comp
3243 -111 common/cmd_bootm.c Can't get kernel subimage os
3244 -112 common/cmd_bootm.c Can't get kernel subimage load address
3245 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3247 120 common/image.c Start initial ramdisk verification
3248 -120 common/image.c Ramdisk FIT image has incorrect format
3249 121 common/image.c Ramdisk FIT image has correct format
3250 122 common/image.c No ramdisk subimage unit name, using configuration
3251 -122 common/image.c Can't get configuration for ramdisk subimage
3252 123 common/image.c Ramdisk unit name specified
3253 -124 common/image.c Can't get ramdisk subimage node offset
3254 125 common/image.c Got ramdisk subimage node offset
3255 -125 common/image.c Ramdisk subimage hash verification failed
3256 126 common/image.c Ramdisk subimage hash verification OK
3257 -126 common/image.c Ramdisk subimage for unsupported architecture
3258 127 common/image.c Architecture check OK
3259 -127 common/image.c Can't get ramdisk subimage data/size
3260 128 common/image.c Got ramdisk subimage data/size
3261 129 common/image.c Can't get ramdisk load address
3262 -129 common/image.c Got ramdisk load address
3264 -130 common/cmd_doc.c Incorrect FIT image format
3265 131 common/cmd_doc.c FIT image format OK
3267 -140 common/cmd_ide.c Incorrect FIT image format
3268 141 common/cmd_ide.c FIT image format OK
3270 -150 common/cmd_nand.c Incorrect FIT image format
3271 151 common/cmd_nand.c FIT image format OK
3273 - legacy image format:
3274 CONFIG_IMAGE_FORMAT_LEGACY
3275 enables the legacy image format support in U-Boot.
3278 enabled if CONFIG_FIT_SIGNATURE is not defined.
3280 CONFIG_DISABLE_IMAGE_LEGACY
3281 disable the legacy image format
3283 This define is introduced, as the legacy image format is
3284 enabled per default for backward compatibility.
3286 - FIT image support:
3287 CONFIG_FIT_DISABLE_SHA256
3288 Supporting SHA256 hashes has quite an impact on binary size.
3289 For constrained systems sha256 hash support can be disabled
3292 TODO(sjg@chromium.org): Adjust this option to be positive,
3293 and move it to Kconfig
3295 - Standalone program support:
3296 CONFIG_STANDALONE_LOAD_ADDR
3298 This option defines a board specific value for the
3299 address where standalone program gets loaded, thus
3300 overwriting the architecture dependent default
3303 - Frame Buffer Address:
3306 Define CONFIG_FB_ADDR if you want to use specific
3307 address for frame buffer. This is typically the case
3308 when using a graphics controller has separate video
3309 memory. U-Boot will then place the frame buffer at
3310 the given address instead of dynamically reserving it
3311 in system RAM by calling lcd_setmem(), which grabs
3312 the memory for the frame buffer depending on the
3313 configured panel size.
3315 Please see board_init_f function.
3317 - Automatic software updates via TFTP server
3319 CONFIG_UPDATE_TFTP_CNT_MAX
3320 CONFIG_UPDATE_TFTP_MSEC_MAX
3322 These options enable and control the auto-update feature;
3323 for a more detailed description refer to doc/README.update.
3325 - MTD Support (mtdparts command, UBI support)
3328 Adds the MTD device infrastructure from the Linux kernel.
3329 Needed for mtdparts command support.
3331 CONFIG_MTD_PARTITIONS
3333 Adds the MTD partitioning infrastructure from the Linux
3334 kernel. Needed for UBI support.
3339 Adds commands for interacting with MTD partitions formatted
3340 with the UBI flash translation layer
3342 Requires also defining CONFIG_RBTREE
3344 CONFIG_UBI_SILENCE_MSG
3346 Make the verbose messages from UBI stop printing. This leaves
3347 warnings and errors enabled.
3350 CONFIG_MTD_UBI_WL_THRESHOLD
3351 This parameter defines the maximum difference between the highest
3352 erase counter value and the lowest erase counter value of eraseblocks
3353 of UBI devices. When this threshold is exceeded, UBI starts performing
3354 wear leveling by means of moving data from eraseblock with low erase
3355 counter to eraseblocks with high erase counter.
3357 The default value should be OK for SLC NAND flashes, NOR flashes and
3358 other flashes which have eraseblock life-cycle 100000 or more.
3359 However, in case of MLC NAND flashes which typically have eraseblock
3360 life-cycle less than 10000, the threshold should be lessened (e.g.,
3361 to 128 or 256, although it does not have to be power of 2).
3365 CONFIG_MTD_UBI_BEB_LIMIT
3366 This option specifies the maximum bad physical eraseblocks UBI
3367 expects on the MTD device (per 1024 eraseblocks). If the
3368 underlying flash does not admit of bad eraseblocks (e.g. NOR
3369 flash), this value is ignored.
3371 NAND datasheets often specify the minimum and maximum NVM
3372 (Number of Valid Blocks) for the flashes' endurance lifetime.
3373 The maximum expected bad eraseblocks per 1024 eraseblocks
3374 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
3375 which gives 20 for most NANDs (MaxNVB is basically the total
3376 count of eraseblocks on the chip).
3378 To put it differently, if this value is 20, UBI will try to
3379 reserve about 1.9% of physical eraseblocks for bad blocks
3380 handling. And that will be 1.9% of eraseblocks on the entire
3381 NAND chip, not just the MTD partition UBI attaches. This means
3382 that if you have, say, a NAND flash chip admits maximum 40 bad
3383 eraseblocks, and it is split on two MTD partitions of the same
3384 size, UBI will reserve 40 eraseblocks when attaching a
3389 CONFIG_MTD_UBI_FASTMAP
3390 Fastmap is a mechanism which allows attaching an UBI device
3391 in nearly constant time. Instead of scanning the whole MTD device it
3392 only has to locate a checkpoint (called fastmap) on the device.
3393 The on-flash fastmap contains all information needed to attach
3394 the device. Using fastmap makes only sense on large devices where
3395 attaching by scanning takes long. UBI will not automatically install
3396 a fastmap on old images, but you can set the UBI parameter
3397 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
3398 that fastmap-enabled images are still usable with UBI implementations
3399 without fastmap support. On typical flash devices the whole fastmap
3400 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
3402 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
3403 Set this parameter to enable fastmap automatically on images
3407 CONFIG_MTD_UBI_FM_DEBUG
3408 Enable UBI fastmap debug
3414 Adds commands for interacting with UBI volumes formatted as
3415 UBIFS. UBIFS is read-only in u-boot.
3417 Requires UBI support as well as CONFIG_LZO
3419 CONFIG_UBIFS_SILENCE_MSG
3421 Make the verbose messages from UBIFS stop printing. This leaves
3422 warnings and errors enabled.
3426 Enable building of SPL globally.
3429 LDSCRIPT for linking the SPL binary.
3431 CONFIG_SPL_MAX_FOOTPRINT
3432 Maximum size in memory allocated to the SPL, BSS included.
3433 When defined, the linker checks that the actual memory
3434 used by SPL from _start to __bss_end does not exceed it.
3435 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3436 must not be both defined at the same time.
3439 Maximum size of the SPL image (text, data, rodata, and
3440 linker lists sections), BSS excluded.
3441 When defined, the linker checks that the actual size does
3444 CONFIG_SPL_TEXT_BASE
3445 TEXT_BASE for linking the SPL binary.
3447 CONFIG_SPL_RELOC_TEXT_BASE
3448 Address to relocate to. If unspecified, this is equal to
3449 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3451 CONFIG_SPL_BSS_START_ADDR
3452 Link address for the BSS within the SPL binary.
3454 CONFIG_SPL_BSS_MAX_SIZE
3455 Maximum size in memory allocated to the SPL BSS.
3456 When defined, the linker checks that the actual memory used
3457 by SPL from __bss_start to __bss_end does not exceed it.
3458 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3459 must not be both defined at the same time.
3462 Adress of the start of the stack SPL will use
3464 CONFIG_SPL_PANIC_ON_RAW_IMAGE
3465 When defined, SPL will panic() if the image it has
3466 loaded does not have a signature.
3467 Defining this is useful when code which loads images
3468 in SPL cannot guarantee that absolutely all read errors
3470 An example is the LPC32XX MLC NAND driver, which will
3471 consider that a completely unreadable NAND block is bad,
3472 and thus should be skipped silently.
3474 CONFIG_SPL_ABORT_ON_RAW_IMAGE
3475 When defined, SPL will proceed to another boot method
3476 if the image it has loaded does not have a signature.
3478 CONFIG_SPL_RELOC_STACK
3479 Adress of the start of the stack SPL will use after
3480 relocation. If unspecified, this is equal to
3483 CONFIG_SYS_SPL_MALLOC_START
3484 Starting address of the malloc pool used in SPL.
3485 When this option is set the full malloc is used in SPL and
3486 it is set up by spl_init() and before that, the simple malloc()
3487 can be used if CONFIG_SYS_MALLOC_F is defined.
3489 CONFIG_SYS_SPL_MALLOC_SIZE
3490 The size of the malloc pool used in SPL.
3492 CONFIG_SPL_FRAMEWORK
3493 Enable the SPL framework under common/. This framework
3494 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3495 NAND loading of the Linux Kernel.
3498 Enable booting directly to an OS from SPL.
3499 See also: doc/README.falcon
3501 CONFIG_SPL_DISPLAY_PRINT
3502 For ARM, enable an optional function to print more information
3503 about the running system.
3505 CONFIG_SPL_INIT_MINIMAL
3506 Arch init code should be built for a very small image
3508 CONFIG_SPL_LIBCOMMON_SUPPORT
3509 Support for common/libcommon.o in SPL binary
3511 CONFIG_SPL_LIBDISK_SUPPORT
3512 Support for disk/libdisk.o in SPL binary
3514 CONFIG_SPL_I2C_SUPPORT
3515 Support for drivers/i2c/libi2c.o in SPL binary
3517 CONFIG_SPL_GPIO_SUPPORT
3518 Support for drivers/gpio/libgpio.o in SPL binary
3520 CONFIG_SPL_MMC_SUPPORT
3521 Support for drivers/mmc/libmmc.o in SPL binary
3523 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3524 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3525 Address and partition on the MMC to load U-Boot from
3526 when the MMC is being used in raw mode.
3528 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
3529 Partition on the MMC to load U-Boot from when the MMC is being
3532 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3533 Sector to load kernel uImage from when MMC is being
3534 used in raw mode (for Falcon mode)
3536 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3537 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3538 Sector and number of sectors to load kernel argument
3539 parameters from when MMC is being used in raw mode
3542 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
3543 Partition on the MMC to load U-Boot from when the MMC is being
3546 CONFIG_SPL_FAT_SUPPORT
3547 Support for fs/fat/libfat.o in SPL binary
3549 CONFIG_SPL_EXT_SUPPORT
3550 Support for EXT filesystem in SPL binary
3552 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
3553 Filename to read to load U-Boot when reading from filesystem
3555 CONFIG_SPL_FS_LOAD_KERNEL_NAME
3556 Filename to read to load kernel uImage when reading
3557 from filesystem (for Falcon mode)
3559 CONFIG_SPL_FS_LOAD_ARGS_NAME
3560 Filename to read to load kernel argument parameters
3561 when reading from filesystem (for Falcon mode)
3563 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3564 Set this for NAND SPL on PPC mpc83xx targets, so that
3565 start.S waits for the rest of the SPL to load before
3566 continuing (the hardware starts execution after just
3567 loading the first page rather than the full 4K).
3569 CONFIG_SPL_SKIP_RELOCATE
3570 Avoid SPL relocation
3572 CONFIG_SPL_NAND_BASE
3573 Include nand_base.c in the SPL. Requires
3574 CONFIG_SPL_NAND_DRIVERS.
3576 CONFIG_SPL_NAND_DRIVERS
3577 SPL uses normal NAND drivers, not minimal drivers.
3580 Include standard software ECC in the SPL
3582 CONFIG_SPL_NAND_SIMPLE
3583 Support for NAND boot using simple NAND drivers that
3584 expose the cmd_ctrl() interface.
3587 Support for a lightweight UBI (fastmap) scanner and
3590 CONFIG_SPL_MTD_SUPPORT
3591 Support for the MTD subsystem within SPL. Useful for
3592 environment on NAND support within SPL.
3594 CONFIG_SPL_NAND_RAW_ONLY
3595 Support to boot only raw u-boot.bin images. Use this only
3596 if you need to save space.
3598 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3599 Set for the SPL on PPC mpc8xxx targets, support for
3600 drivers/ddr/fsl/libddr.o in SPL binary.
3602 CONFIG_SPL_COMMON_INIT_DDR
3603 Set for common ddr init with serial presence detect in
3606 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3607 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3608 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3609 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3610 CONFIG_SYS_NAND_ECCBYTES
3611 Defines the size and behavior of the NAND that SPL uses
3614 CONFIG_SPL_NAND_BOOT
3615 Add support NAND boot
3617 CONFIG_SYS_NAND_U_BOOT_OFFS
3618 Location in NAND to read U-Boot from
3620 CONFIG_SYS_NAND_U_BOOT_DST
3621 Location in memory to load U-Boot to
3623 CONFIG_SYS_NAND_U_BOOT_SIZE
3624 Size of image to load
3626 CONFIG_SYS_NAND_U_BOOT_START
3627 Entry point in loaded image to jump to
3629 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3630 Define this if you need to first read the OOB and then the
3631 data. This is used, for example, on davinci platforms.
3633 CONFIG_SPL_OMAP3_ID_NAND
3634 Support for an OMAP3-specific set of functions to return the
3635 ID and MFR of the first attached NAND chip, if present.
3637 CONFIG_SPL_SERIAL_SUPPORT
3638 Support for drivers/serial/libserial.o in SPL binary
3640 CONFIG_SPL_SPI_FLASH_SUPPORT
3641 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3643 CONFIG_SPL_SPI_SUPPORT
3644 Support for drivers/spi/libspi.o in SPL binary
3646 CONFIG_SPL_RAM_DEVICE
3647 Support for running image already present in ram, in SPL binary
3649 CONFIG_SPL_LIBGENERIC_SUPPORT
3650 Support for lib/libgeneric.o in SPL binary
3652 CONFIG_SPL_ENV_SUPPORT
3653 Support for the environment operating in SPL binary
3655 CONFIG_SPL_NET_SUPPORT
3656 Support for the net/libnet.o in SPL binary.
3657 It conflicts with SPL env from storage medium specified by
3658 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3661 Image offset to which the SPL should be padded before appending
3662 the SPL payload. By default, this is defined as
3663 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3664 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3665 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3668 Final target image containing SPL and payload. Some SPLs
3669 use an arch-specific makefile fragment instead, for
3670 example if more than one image needs to be produced.
3672 CONFIG_FIT_SPL_PRINT
3673 Printing information about a FIT image adds quite a bit of
3674 code to SPL. So this is normally disabled in SPL. Use this
3675 option to re-enable it. This will affect the output of the
3676 bootm command when booting a FIT image.
3680 Enable building of TPL globally.
3683 Image offset to which the TPL should be padded before appending
3684 the TPL payload. By default, this is defined as
3685 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3686 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3687 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3689 - Interrupt support (PPC):
3691 There are common interrupt_init() and timer_interrupt()
3692 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3693 for CPU specific initialization. interrupt_init_cpu()
3694 should set decrementer_count to appropriate value. If
3695 CPU resets decrementer automatically after interrupt
3696 (ppc4xx) it should set decrementer_count to zero.
3697 timer_interrupt() calls timer_interrupt_cpu() for CPU
3698 specific handling. If board has watchdog / status_led
3699 / other_activity_monitor it works automatically from
3700 general timer_interrupt().
3703 Board initialization settings:
3704 ------------------------------
3706 During Initialization u-boot calls a number of board specific functions
3707 to allow the preparation of board specific prerequisites, e.g. pin setup
3708 before drivers are initialized. To enable these callbacks the
3709 following configuration macros have to be defined. Currently this is
3710 architecture specific, so please check arch/your_architecture/lib/board.c
3711 typically in board_init_f() and board_init_r().
3713 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3714 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3715 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3716 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3718 Configuration Settings:
3719 -----------------------
3721 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3722 Optionally it can be defined to support 64-bit memory commands.
3724 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3725 undefine this when you're short of memory.
3727 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3728 width of the commands listed in the 'help' command output.
3730 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3731 prompt for user input.
3733 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3735 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3737 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3739 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3740 the application (usually a Linux kernel) when it is
3743 - CONFIG_SYS_BAUDRATE_TABLE:
3744 List of legal baudrate settings for this board.
3746 - CONFIG_SYS_CONSOLE_INFO_QUIET
3747 Suppress display of console information at boot.
3749 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3750 If the board specific function
3751 extern int overwrite_console (void);
3752 returns 1, the stdin, stderr and stdout are switched to the
3753 serial port, else the settings in the environment are used.
3755 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3756 Enable the call to overwrite_console().
3758 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3759 Enable overwrite of previous console environment settings.
3761 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3762 Begin and End addresses of the area used by the
3765 - CONFIG_SYS_ALT_MEMTEST:
3766 Enable an alternate, more extensive memory test.
3768 - CONFIG_SYS_MEMTEST_SCRATCH:
3769 Scratch address used by the alternate memory test
3770 You only need to set this if address zero isn't writeable
3772 - CONFIG_SYS_MEM_RESERVE_SECURE
3773 Only implemented for ARMv8 for now.
3774 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
3775 is substracted from total RAM and won't be reported to OS.
3776 This memory can be used as secure memory. A variable
3777 gd->arch.secure_ram is used to track the location. In systems
3778 the RAM base is not zero, or RAM is divided into banks,
3779 this variable needs to be recalcuated to get the address.
3781 - CONFIG_SYS_MEM_TOP_HIDE:
3782 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3783 this specified memory area will get subtracted from the top
3784 (end) of RAM and won't get "touched" at all by U-Boot. By
3785 fixing up gd->ram_size the Linux kernel should gets passed
3786 the now "corrected" memory size and won't touch it either.
3787 This should work for arch/ppc and arch/powerpc. Only Linux
3788 board ports in arch/powerpc with bootwrapper support that
3789 recalculate the memory size from the SDRAM controller setup
3790 will have to get fixed in Linux additionally.
3792 This option can be used as a workaround for the 440EPx/GRx
3793 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3796 WARNING: Please make sure that this value is a multiple of
3797 the Linux page size (normally 4k). If this is not the case,
3798 then the end address of the Linux memory will be located at a
3799 non page size aligned address and this could cause major
3802 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3803 Enable temporary baudrate change while serial download
3805 - CONFIG_SYS_SDRAM_BASE:
3806 Physical start address of SDRAM. _Must_ be 0 here.
3808 - CONFIG_SYS_MBIO_BASE:
3809 Physical start address of Motherboard I/O (if using a
3812 - CONFIG_SYS_FLASH_BASE:
3813 Physical start address of Flash memory.
3815 - CONFIG_SYS_MONITOR_BASE:
3816 Physical start address of boot monitor code (set by
3817 make config files to be same as the text base address
3818 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3819 CONFIG_SYS_FLASH_BASE when booting from flash.
3821 - CONFIG_SYS_MONITOR_LEN:
3822 Size of memory reserved for monitor code, used to
3823 determine _at_compile_time_ (!) if the environment is
3824 embedded within the U-Boot image, or in a separate
3827 - CONFIG_SYS_MALLOC_LEN:
3828 Size of DRAM reserved for malloc() use.
3830 - CONFIG_SYS_MALLOC_F_LEN
3831 Size of the malloc() pool for use before relocation. If
3832 this is defined, then a very simple malloc() implementation
3833 will become available before relocation. The address is just
3834 below the global data, and the stack is moved down to make
3837 This feature allocates regions with increasing addresses
3838 within the region. calloc() is supported, but realloc()
3839 is not available. free() is supported but does nothing.
3840 The memory will be freed (or in fact just forgotten) when
3841 U-Boot relocates itself.
3843 - CONFIG_SYS_MALLOC_SIMPLE
3844 Provides a simple and small malloc() and calloc() for those
3845 boards which do not use the full malloc in SPL (which is
3846 enabled with CONFIG_SYS_SPL_MALLOC_START).
3848 - CONFIG_SYS_NONCACHED_MEMORY:
3849 Size of non-cached memory area. This area of memory will be
3850 typically located right below the malloc() area and mapped
3851 uncached in the MMU. This is useful for drivers that would
3852 otherwise require a lot of explicit cache maintenance. For
3853 some drivers it's also impossible to properly maintain the
3854 cache. For example if the regions that need to be flushed
3855 are not a multiple of the cache-line size, *and* padding
3856 cannot be allocated between the regions to align them (i.e.
3857 if the HW requires a contiguous array of regions, and the
3858 size of each region is not cache-aligned), then a flush of
3859 one region may result in overwriting data that hardware has
3860 written to another region in the same cache-line. This can
3861 happen for example in network drivers where descriptors for
3862 buffers are typically smaller than the CPU cache-line (e.g.
3863 16 bytes vs. 32 or 64 bytes).
3865 Non-cached memory is only supported on 32-bit ARM at present.
3867 - CONFIG_SYS_BOOTM_LEN:
3868 Normally compressed uImages are limited to an
3869 uncompressed size of 8 MBytes. If this is not enough,
3870 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3871 to adjust this setting to your needs.
3873 - CONFIG_SYS_BOOTMAPSZ:
3874 Maximum size of memory mapped by the startup code of
3875 the Linux kernel; all data that must be processed by
3876 the Linux kernel (bd_info, boot arguments, FDT blob if
3877 used) must be put below this limit, unless "bootm_low"
3878 environment variable is defined and non-zero. In such case
3879 all data for the Linux kernel must be between "bootm_low"
3880 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3881 variable "bootm_mapsize" will override the value of
3882 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3883 then the value in "bootm_size" will be used instead.
3885 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3886 Enable initrd_high functionality. If defined then the
3887 initrd_high feature is enabled and the bootm ramdisk subcommand
3890 - CONFIG_SYS_BOOT_GET_CMDLINE:
3891 Enables allocating and saving kernel cmdline in space between
3892 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3894 - CONFIG_SYS_BOOT_GET_KBD:
3895 Enables allocating and saving a kernel copy of the bd_info in
3896 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3898 - CONFIG_SYS_MAX_FLASH_BANKS:
3899 Max number of Flash memory banks
3901 - CONFIG_SYS_MAX_FLASH_SECT:
3902 Max number of sectors on a Flash chip
3904 - CONFIG_SYS_FLASH_ERASE_TOUT:
3905 Timeout for Flash erase operations (in ms)
3907 - CONFIG_SYS_FLASH_WRITE_TOUT:
3908 Timeout for Flash write operations (in ms)
3910 - CONFIG_SYS_FLASH_LOCK_TOUT
3911 Timeout for Flash set sector lock bit operation (in ms)
3913 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3914 Timeout for Flash clear lock bits operation (in ms)
3916 - CONFIG_SYS_FLASH_PROTECTION
3917 If defined, hardware flash sectors protection is used
3918 instead of U-Boot software protection.
3920 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3922 Enable TFTP transfers directly to flash memory;
3923 without this option such a download has to be
3924 performed in two steps: (1) download to RAM, and (2)
3925 copy from RAM to flash.
3927 The two-step approach is usually more reliable, since
3928 you can check if the download worked before you erase
3929 the flash, but in some situations (when system RAM is
3930 too limited to allow for a temporary copy of the
3931 downloaded image) this option may be very useful.
3933 - CONFIG_SYS_FLASH_CFI:
3934 Define if the flash driver uses extra elements in the
3935 common flash structure for storing flash geometry.
3937 - CONFIG_FLASH_CFI_DRIVER
3938 This option also enables the building of the cfi_flash driver
3939 in the drivers directory
3941 - CONFIG_FLASH_CFI_MTD
3942 This option enables the building of the cfi_mtd driver
3943 in the drivers directory. The driver exports CFI flash
3946 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3947 Use buffered writes to flash.
3949 - CONFIG_FLASH_SPANSION_S29WS_N
3950 s29ws-n MirrorBit flash has non-standard addresses for buffered
3953 - CONFIG_SYS_FLASH_QUIET_TEST
3954 If this option is defined, the common CFI flash doesn't
3955 print it's warning upon not recognized FLASH banks. This
3956 is useful, if some of the configured banks are only
3957 optionally available.
3959 - CONFIG_FLASH_SHOW_PROGRESS
3960 If defined (must be an integer), print out countdown
3961 digits and dots. Recommended value: 45 (9..1) for 80
3962 column displays, 15 (3..1) for 40 column displays.
3964 - CONFIG_FLASH_VERIFY
3965 If defined, the content of the flash (destination) is compared
3966 against the source after the write operation. An error message
3967 will be printed when the contents are not identical.
3968 Please note that this option is useless in nearly all cases,
3969 since such flash programming errors usually are detected earlier
3970 while unprotecting/erasing/programming. Please only enable
3971 this option if you really know what you are doing.
3973 - CONFIG_SYS_RX_ETH_BUFFER:
3974 Defines the number of Ethernet receive buffers. On some
3975 Ethernet controllers it is recommended to set this value
3976 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3977 buffers can be full shortly after enabling the interface
3978 on high Ethernet traffic.
3979 Defaults to 4 if not defined.
3981 - CONFIG_ENV_MAX_ENTRIES
3983 Maximum number of entries in the hash table that is used
3984 internally to store the environment settings. The default
3985 setting is supposed to be generous and should work in most
3986 cases. This setting can be used to tune behaviour; see
3987 lib/hashtable.c for details.
3989 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3990 - CONFIG_ENV_FLAGS_LIST_STATIC
3991 Enable validation of the values given to environment variables when
3992 calling env set. Variables can be restricted to only decimal,
3993 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3994 the variables can also be restricted to IP address or MAC address.
3996 The format of the list is:
3997 type_attribute = [s|d|x|b|i|m]
3998 access_attribute = [a|r|o|c]
3999 attributes = type_attribute[access_attribute]
4000 entry = variable_name[:attributes]
4003 The type attributes are:
4004 s - String (default)
4007 b - Boolean ([1yYtT|0nNfF])
4011 The access attributes are:
4017 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4018 Define this to a list (string) to define the ".flags"
4019 environment variable in the default or embedded environment.
4021 - CONFIG_ENV_FLAGS_LIST_STATIC
4022 Define this to a list (string) to define validation that
4023 should be done if an entry is not found in the ".flags"
4024 environment variable. To override a setting in the static
4025 list, simply add an entry for the same variable name to the
4028 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
4029 regular expression. This allows multiple variables to define the same
4030 flags without explicitly listing them for each variable.
4032 - CONFIG_ENV_ACCESS_IGNORE_FORCE
4033 If defined, don't allow the -f switch to env set override variable
4036 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
4037 This is set by OMAP boards for the max time that reset should
4038 be asserted. See doc/README.omap-reset-time for details on how
4039 the value can be calculated on a given board.
4042 If stdint.h is available with your toolchain you can define this
4043 option to enable it. You can provide option 'USE_STDINT=1' when
4044 building U-Boot to enable this.
4046 The following definitions that deal with the placement and management
4047 of environment data (variable area); in general, we support the
4048 following configurations:
4050 - CONFIG_BUILD_ENVCRC:
4052 Builds up envcrc with the target environment so that external utils
4053 may easily extract it and embed it in final U-Boot images.
4055 - CONFIG_ENV_IS_IN_FLASH:
4057 Define this if the environment is in flash memory.
4059 a) The environment occupies one whole flash sector, which is
4060 "embedded" in the text segment with the U-Boot code. This
4061 happens usually with "bottom boot sector" or "top boot
4062 sector" type flash chips, which have several smaller
4063 sectors at the start or the end. For instance, such a
4064 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
4065 such a case you would place the environment in one of the
4066 4 kB sectors - with U-Boot code before and after it. With
4067 "top boot sector" type flash chips, you would put the
4068 environment in one of the last sectors, leaving a gap
4069 between U-Boot and the environment.
4071 - CONFIG_ENV_OFFSET:
4073 Offset of environment data (variable area) to the
4074 beginning of flash memory; for instance, with bottom boot
4075 type flash chips the second sector can be used: the offset
4076 for this sector is given here.
4078 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
4082 This is just another way to specify the start address of
4083 the flash sector containing the environment (instead of
4086 - CONFIG_ENV_SECT_SIZE:
4088 Size of the sector containing the environment.
4091 b) Sometimes flash chips have few, equal sized, BIG sectors.
4092 In such a case you don't want to spend a whole sector for
4097 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
4098 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
4099 of this flash sector for the environment. This saves
4100 memory for the RAM copy of the environment.
4102 It may also save flash memory if you decide to use this
4103 when your environment is "embedded" within U-Boot code,
4104 since then the remainder of the flash sector could be used
4105 for U-Boot code. It should be pointed out that this is
4106 STRONGLY DISCOURAGED from a robustness point of view:
4107 updating the environment in flash makes it always
4108 necessary to erase the WHOLE sector. If something goes
4109 wrong before the contents has been restored from a copy in
4110 RAM, your target system will be dead.
4112 - CONFIG_ENV_ADDR_REDUND
4113 CONFIG_ENV_SIZE_REDUND
4115 These settings describe a second storage area used to hold
4116 a redundant copy of the environment data, so that there is
4117 a valid backup copy in case there is a power failure during
4118 a "saveenv" operation.
4120 BE CAREFUL! Any changes to the flash layout, and some changes to the
4121 source code will make it necessary to adapt <board>/u-boot.lds*
4125 - CONFIG_ENV_IS_IN_NVRAM:
4127 Define this if you have some non-volatile memory device
4128 (NVRAM, battery buffered SRAM) which you want to use for the
4134 These two #defines are used to determine the memory area you
4135 want to use for environment. It is assumed that this memory
4136 can just be read and written to, without any special
4139 BE CAREFUL! The first access to the environment happens quite early
4140 in U-Boot initialization (when we try to get the setting of for the
4141 console baudrate). You *MUST* have mapped your NVRAM area then, or
4144 Please note that even with NVRAM we still use a copy of the
4145 environment in RAM: we could work on NVRAM directly, but we want to
4146 keep settings there always unmodified except somebody uses "saveenv"
4147 to save the current settings.
4150 - CONFIG_ENV_IS_IN_EEPROM:
4152 Use this if you have an EEPROM or similar serial access
4153 device and a driver for it.
4155 - CONFIG_ENV_OFFSET:
4158 These two #defines specify the offset and size of the
4159 environment area within the total memory of your EEPROM.
4161 - CONFIG_SYS_I2C_EEPROM_ADDR:
4162 If defined, specified the chip address of the EEPROM device.
4163 The default address is zero.
4165 - CONFIG_SYS_I2C_EEPROM_BUS:
4166 If defined, specified the i2c bus of the EEPROM device.
4168 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
4169 If defined, the number of bits used to address bytes in a
4170 single page in the EEPROM device. A 64 byte page, for example
4171 would require six bits.
4173 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
4174 If defined, the number of milliseconds to delay between
4175 page writes. The default is zero milliseconds.
4177 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
4178 The length in bytes of the EEPROM memory array address. Note
4179 that this is NOT the chip address length!
4181 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
4182 EEPROM chips that implement "address overflow" are ones
4183 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
4184 address and the extra bits end up in the "chip address" bit
4185 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
4188 Note that we consider the length of the address field to
4189 still be one byte because the extra address bits are hidden
4190 in the chip address.
4192 - CONFIG_SYS_EEPROM_SIZE:
4193 The size in bytes of the EEPROM device.
4195 - CONFIG_ENV_EEPROM_IS_ON_I2C
4196 define this, if you have I2C and SPI activated, and your
4197 EEPROM, which holds the environment, is on the I2C bus.
4199 - CONFIG_I2C_ENV_EEPROM_BUS
4200 if you have an Environment on an EEPROM reached over
4201 I2C muxes, you can define here, how to reach this
4202 EEPROM. For example:
4204 #define CONFIG_I2C_ENV_EEPROM_BUS 1
4206 EEPROM which holds the environment, is reached over
4207 a pca9547 i2c mux with address 0x70, channel 3.
4209 - CONFIG_ENV_IS_IN_DATAFLASH:
4211 Define this if you have a DataFlash memory device which you
4212 want to use for the environment.
4214 - CONFIG_ENV_OFFSET:
4218 These three #defines specify the offset and size of the
4219 environment area within the total memory of your DataFlash placed
4220 at the specified address.
4222 - CONFIG_ENV_IS_IN_SPI_FLASH:
4224 Define this if you have a SPI Flash memory device which you
4225 want to use for the environment.
4227 - CONFIG_ENV_OFFSET:
4230 These two #defines specify the offset and size of the
4231 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
4232 aligned to an erase sector boundary.
4234 - CONFIG_ENV_SECT_SIZE:
4236 Define the SPI flash's sector size.
4238 - CONFIG_ENV_OFFSET_REDUND (optional):
4240 This setting describes a second storage area of CONFIG_ENV_SIZE
4241 size used to hold a redundant copy of the environment data, so
4242 that there is a valid backup copy in case there is a power failure
4243 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4244 aligned to an erase sector boundary.
4246 - CONFIG_ENV_SPI_BUS (optional):
4247 - CONFIG_ENV_SPI_CS (optional):
4249 Define the SPI bus and chip select. If not defined they will be 0.
4251 - CONFIG_ENV_SPI_MAX_HZ (optional):
4253 Define the SPI max work clock. If not defined then use 1MHz.
4255 - CONFIG_ENV_SPI_MODE (optional):
4257 Define the SPI work mode. If not defined then use SPI_MODE_3.
4259 - CONFIG_ENV_IS_IN_REMOTE:
4261 Define this if you have a remote memory space which you
4262 want to use for the local device's environment.
4267 These two #defines specify the address and size of the
4268 environment area within the remote memory space. The
4269 local device can get the environment from remote memory
4270 space by SRIO or PCIE links.
4272 BE CAREFUL! For some special cases, the local device can not use
4273 "saveenv" command. For example, the local device will get the
4274 environment stored in a remote NOR flash by SRIO or PCIE link,
4275 but it can not erase, write this NOR flash by SRIO or PCIE interface.
4277 - CONFIG_ENV_IS_IN_NAND:
4279 Define this if you have a NAND device which you want to use
4280 for the environment.
4282 - CONFIG_ENV_OFFSET:
4285 These two #defines specify the offset and size of the environment
4286 area within the first NAND device. CONFIG_ENV_OFFSET must be
4287 aligned to an erase block boundary.
4289 - CONFIG_ENV_OFFSET_REDUND (optional):
4291 This setting describes a second storage area of CONFIG_ENV_SIZE
4292 size used to hold a redundant copy of the environment data, so
4293 that there is a valid backup copy in case there is a power failure
4294 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4295 aligned to an erase block boundary.
4297 - CONFIG_ENV_RANGE (optional):
4299 Specifies the length of the region in which the environment
4300 can be written. This should be a multiple of the NAND device's
4301 block size. Specifying a range with more erase blocks than
4302 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
4303 the range to be avoided.
4305 - CONFIG_ENV_OFFSET_OOB (optional):
4307 Enables support for dynamically retrieving the offset of the
4308 environment from block zero's out-of-band data. The
4309 "nand env.oob" command can be used to record this offset.
4310 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4311 using CONFIG_ENV_OFFSET_OOB.
4313 - CONFIG_NAND_ENV_DST
4315 Defines address in RAM to which the nand_spl code should copy the
4316 environment. If redundant environment is used, it will be copied to
4317 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4319 - CONFIG_ENV_IS_IN_UBI:
4321 Define this if you have an UBI volume that you want to use for the
4322 environment. This has the benefit of wear-leveling the environment
4323 accesses, which is important on NAND.
4325 - CONFIG_ENV_UBI_PART:
4327 Define this to a string that is the mtd partition containing the UBI.
4329 - CONFIG_ENV_UBI_VOLUME:
4331 Define this to the name of the volume that you want to store the
4334 - CONFIG_ENV_UBI_VOLUME_REDUND:
4336 Define this to the name of another volume to store a second copy of
4337 the environment in. This will enable redundant environments in UBI.
4338 It is assumed that both volumes are in the same MTD partition.
4340 - CONFIG_UBI_SILENCE_MSG
4341 - CONFIG_UBIFS_SILENCE_MSG
4343 You will probably want to define these to avoid a really noisy system
4344 when storing the env in UBI.
4346 - CONFIG_ENV_IS_IN_FAT:
4347 Define this if you want to use the FAT file system for the environment.
4349 - FAT_ENV_INTERFACE:
4351 Define this to a string that is the name of the block device.
4353 - FAT_ENV_DEV_AND_PART:
4355 Define this to a string to specify the partition of the device. It can
4358 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
4359 - "D:P": device D partition P. Error occurs if device D has no
4362 - "D" or "D:": device D partition 1 if device D has partition
4363 table, or the whole device D if has no partition
4365 - "D:auto": first partition in device D with bootable flag set.
4366 If none, first valid partition in device D. If no
4367 partition table then means device D.
4371 It's a string of the FAT file name. This file use to store the
4375 This should be defined. Otherwise it cannot save the environment file.
4377 - CONFIG_ENV_IS_IN_MMC:
4379 Define this if you have an MMC device which you want to use for the
4382 - CONFIG_SYS_MMC_ENV_DEV:
4384 Specifies which MMC device the environment is stored in.
4386 - CONFIG_SYS_MMC_ENV_PART (optional):
4388 Specifies which MMC partition the environment is stored in. If not
4389 set, defaults to partition 0, the user area. Common values might be
4390 1 (first MMC boot partition), 2 (second MMC boot partition).
4392 - CONFIG_ENV_OFFSET:
4395 These two #defines specify the offset and size of the environment
4396 area within the specified MMC device.
4398 If offset is positive (the usual case), it is treated as relative to
4399 the start of the MMC partition. If offset is negative, it is treated
4400 as relative to the end of the MMC partition. This can be useful if
4401 your board may be fitted with different MMC devices, which have
4402 different sizes for the MMC partitions, and you always want the
4403 environment placed at the very end of the partition, to leave the
4404 maximum possible space before it, to store other data.
4406 These two values are in units of bytes, but must be aligned to an
4407 MMC sector boundary.
4409 - CONFIG_ENV_OFFSET_REDUND (optional):
4411 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4412 hold a redundant copy of the environment data. This provides a
4413 valid backup copy in case the other copy is corrupted, e.g. due
4414 to a power failure during a "saveenv" operation.
4416 This value may also be positive or negative; this is handled in the
4417 same way as CONFIG_ENV_OFFSET.
4419 This value is also in units of bytes, but must also be aligned to
4420 an MMC sector boundary.
4422 - CONFIG_ENV_SIZE_REDUND (optional):
4424 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4425 set. If this value is set, it must be set to the same value as
4428 - CONFIG_SYS_SPI_INIT_OFFSET
4430 Defines offset to the initial SPI buffer area in DPRAM. The
4431 area is used at an early stage (ROM part) if the environment
4432 is configured to reside in the SPI EEPROM: We need a 520 byte
4433 scratch DPRAM area. It is used between the two initialization
4434 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4435 to be a good choice since it makes it far enough from the
4436 start of the data area as well as from the stack pointer.
4438 Please note that the environment is read-only until the monitor
4439 has been relocated to RAM and a RAM copy of the environment has been
4440 created; also, when using EEPROM you will have to use getenv_f()
4441 until then to read environment variables.
4443 The environment is protected by a CRC32 checksum. Before the monitor
4444 is relocated into RAM, as a result of a bad CRC you will be working
4445 with the compiled-in default environment - *silently*!!! [This is
4446 necessary, because the first environment variable we need is the
4447 "baudrate" setting for the console - if we have a bad CRC, we don't
4448 have any device yet where we could complain.]
4450 Note: once the monitor has been relocated, then it will complain if
4451 the default environment is used; a new CRC is computed as soon as you
4452 use the "saveenv" command to store a valid environment.
4454 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4455 Echo the inverted Ethernet link state to the fault LED.
4457 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4458 also needs to be defined.
4460 - CONFIG_SYS_FAULT_MII_ADDR:
4461 MII address of the PHY to check for the Ethernet link state.
4463 - CONFIG_NS16550_MIN_FUNCTIONS:
4464 Define this if you desire to only have use of the NS16550_init
4465 and NS16550_putc functions for the serial driver located at
4466 drivers/serial/ns16550.c. This option is useful for saving
4467 space for already greatly restricted images, including but not
4468 limited to NAND_SPL configurations.
4470 - CONFIG_DISPLAY_BOARDINFO
4471 Display information about the board that U-Boot is running on
4472 when U-Boot starts up. The board function checkboard() is called
4475 - CONFIG_DISPLAY_BOARDINFO_LATE
4476 Similar to the previous option, but display this information
4477 later, once stdio is running and output goes to the LCD, if
4480 - CONFIG_BOARD_SIZE_LIMIT:
4481 Maximum size of the U-Boot image. When defined, the
4482 build system checks that the actual size does not
4485 Low Level (hardware related) configuration options:
4486 ---------------------------------------------------
4488 - CONFIG_SYS_CACHELINE_SIZE:
4489 Cache Line Size of the CPU.
4491 - CONFIG_SYS_DEFAULT_IMMR:
4492 Default address of the IMMR after system reset.
4494 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4495 and RPXsuper) to be able to adjust the position of
4496 the IMMR register after a reset.
4498 - CONFIG_SYS_CCSRBAR_DEFAULT:
4499 Default (power-on reset) physical address of CCSR on Freescale
4502 - CONFIG_SYS_CCSRBAR:
4503 Virtual address of CCSR. On a 32-bit build, this is typically
4504 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4506 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4507 for cross-platform code that uses that macro instead.
4509 - CONFIG_SYS_CCSRBAR_PHYS:
4510 Physical address of CCSR. CCSR can be relocated to a new
4511 physical address, if desired. In this case, this macro should
4512 be set to that address. Otherwise, it should be set to the
4513 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4514 is typically relocated on 36-bit builds. It is recommended
4515 that this macro be defined via the _HIGH and _LOW macros:
4517 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4518 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4520 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4521 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4522 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4523 used in assembly code, so it must not contain typecasts or
4524 integer size suffixes (e.g. "ULL").
4526 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4527 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4528 used in assembly code, so it must not contain typecasts or
4529 integer size suffixes (e.g. "ULL").
4531 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4532 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4533 forced to a value that ensures that CCSR is not relocated.
4535 - Floppy Disk Support:
4536 CONFIG_SYS_FDC_DRIVE_NUMBER
4538 the default drive number (default value 0)
4540 CONFIG_SYS_ISA_IO_STRIDE
4542 defines the spacing between FDC chipset registers
4545 CONFIG_SYS_ISA_IO_OFFSET
4547 defines the offset of register from address. It
4548 depends on which part of the data bus is connected to
4549 the FDC chipset. (default value 0)
4551 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4552 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4555 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4556 fdc_hw_init() is called at the beginning of the FDC
4557 setup. fdc_hw_init() must be provided by the board
4558 source code. It is used to make hardware-dependent
4562 Most IDE controllers were designed to be connected with PCI
4563 interface. Only few of them were designed for AHB interface.
4564 When software is doing ATA command and data transfer to
4565 IDE devices through IDE-AHB controller, some additional
4566 registers accessing to these kind of IDE-AHB controller
4569 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4570 DO NOT CHANGE unless you know exactly what you're
4571 doing! (11-4) [MPC8xx/82xx systems only]
4573 - CONFIG_SYS_INIT_RAM_ADDR:
4575 Start address of memory area that can be used for
4576 initial data and stack; please note that this must be
4577 writable memory that is working WITHOUT special
4578 initialization, i. e. you CANNOT use normal RAM which
4579 will become available only after programming the
4580 memory controller and running certain initialization
4583 U-Boot uses the following memory types:
4584 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4585 - MPC824X: data cache
4586 - PPC4xx: data cache
4588 - CONFIG_SYS_GBL_DATA_OFFSET:
4590 Offset of the initial data structure in the memory
4591 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4592 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4593 data is located at the end of the available space
4594 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4595 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4596 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4597 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4600 On the MPC824X (or other systems that use the data
4601 cache for initial memory) the address chosen for
4602 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4603 point to an otherwise UNUSED address space between
4604 the top of RAM and the start of the PCI space.
4606 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4608 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4610 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4612 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4614 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4616 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4618 - CONFIG_SYS_OR_TIMING_SDRAM:
4621 - CONFIG_SYS_MAMR_PTA:
4622 periodic timer for refresh
4624 - CONFIG_SYS_DER: Debug Event Register (37-47)
4626 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4627 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4628 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4629 CONFIG_SYS_BR1_PRELIM:
4630 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4632 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4633 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4634 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4635 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4637 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4638 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4639 Machine Mode Register and Memory Periodic Timer
4640 Prescaler definitions (SDRAM timing)
4642 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4643 enable I2C microcode relocation patch (MPC8xx);
4644 define relocation offset in DPRAM [DSP2]
4646 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4647 enable SMC microcode relocation patch (MPC8xx);
4648 define relocation offset in DPRAM [SMC1]
4650 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4651 enable SPI microcode relocation patch (MPC8xx);
4652 define relocation offset in DPRAM [SCC4]
4654 - CONFIG_SYS_USE_OSCCLK:
4655 Use OSCM clock mode on MBX8xx board. Be careful,
4656 wrong setting might damage your board. Read
4657 doc/README.MBX before setting this variable!
4659 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4660 Offset of the bootmode word in DPRAM used by post
4661 (Power On Self Tests). This definition overrides
4662 #define'd default value in commproc.h resp.
4665 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4666 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4667 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4668 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4669 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4670 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4671 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4672 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4673 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4675 - CONFIG_PCI_DISABLE_PCIE:
4676 Disable PCI-Express on systems where it is supported but not
4679 - CONFIG_PCI_ENUM_ONLY
4680 Only scan through and get the devices on the buses.
4681 Don't do any setup work, presumably because someone or
4682 something has already done it, and we don't need to do it
4683 a second time. Useful for platforms that are pre-booted
4684 by coreboot or similar.
4686 - CONFIG_PCI_INDIRECT_BRIDGE:
4687 Enable support for indirect PCI bridges.
4690 Chip has SRIO or not
4693 Board has SRIO 1 port available
4696 Board has SRIO 2 port available
4698 - CONFIG_SRIO_PCIE_BOOT_MASTER
4699 Board can support master function for Boot from SRIO and PCIE
4701 - CONFIG_SYS_SRIOn_MEM_VIRT:
4702 Virtual Address of SRIO port 'n' memory region
4704 - CONFIG_SYS_SRIOn_MEM_PHYS:
4705 Physical Address of SRIO port 'n' memory region
4707 - CONFIG_SYS_SRIOn_MEM_SIZE:
4708 Size of SRIO port 'n' memory region
4710 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4711 Defined to tell the NAND controller that the NAND chip is using
4713 Not all NAND drivers use this symbol.
4714 Example of drivers that use it:
4715 - drivers/mtd/nand/ndfc.c
4716 - drivers/mtd/nand/mxc_nand.c
4718 - CONFIG_SYS_NDFC_EBC0_CFG
4719 Sets the EBC0_CFG register for the NDFC. If not defined
4720 a default value will be used.
4723 Get DDR timing information from an I2C EEPROM. Common
4724 with pluggable memory modules such as SODIMMs
4727 I2C address of the SPD EEPROM
4729 - CONFIG_SYS_SPD_BUS_NUM
4730 If SPD EEPROM is on an I2C bus other than the first
4731 one, specify here. Note that the value must resolve
4732 to something your driver can deal with.
4734 - CONFIG_SYS_DDR_RAW_TIMING
4735 Get DDR timing information from other than SPD. Common with
4736 soldered DDR chips onboard without SPD. DDR raw timing
4737 parameters are extracted from datasheet and hard-coded into
4738 header files or board specific files.
4740 - CONFIG_FSL_DDR_INTERACTIVE
4741 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4743 - CONFIG_FSL_DDR_SYNC_REFRESH
4744 Enable sync of refresh for multiple controllers.
4746 - CONFIG_FSL_DDR_BIST
4747 Enable built-in memory test for Freescale DDR controllers.
4749 - CONFIG_SYS_83XX_DDR_USES_CS0
4750 Only for 83xx systems. If specified, then DDR should
4751 be configured using CS0 and CS1 instead of CS2 and CS3.
4753 - CONFIG_ETHER_ON_FEC[12]
4754 Define to enable FEC[12] on a 8xx series processor.
4756 - CONFIG_FEC[12]_PHY
4757 Define to the hardcoded PHY address which corresponds
4758 to the given FEC; i. e.
4759 #define CONFIG_FEC1_PHY 4
4760 means that the PHY with address 4 is connected to FEC1
4762 When set to -1, means to probe for first available.
4764 - CONFIG_FEC[12]_PHY_NORXERR
4765 The PHY does not have a RXERR line (RMII only).
4766 (so program the FEC to ignore it).
4769 Enable RMII mode for all FECs.
4770 Note that this is a global option, we can't
4771 have one FEC in standard MII mode and another in RMII mode.
4773 - CONFIG_CRC32_VERIFY
4774 Add a verify option to the crc32 command.
4777 => crc32 -v <address> <count> <crc32>
4779 Where address/count indicate a memory area
4780 and crc32 is the correct crc32 which the
4784 Add the "loopw" memory command. This only takes effect if
4785 the memory commands are activated globally (CONFIG_CMD_MEM).
4788 Add the "mdc" and "mwc" memory commands. These are cyclic
4793 This command will print 4 bytes (10,11,12,13) each 500 ms.
4795 => mwc.l 100 12345678 10
4796 This command will write 12345678 to address 100 all 10 ms.
4798 This only takes effect if the memory commands are activated
4799 globally (CONFIG_CMD_MEM).
4801 - CONFIG_SKIP_LOWLEVEL_INIT
4802 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4803 low level initializations (like setting up the memory
4804 controller) are omitted and/or U-Boot does not
4805 relocate itself into RAM.
4807 Normally this variable MUST NOT be defined. The only
4808 exception is when U-Boot is loaded (to RAM) by some
4809 other boot loader or by a debugger which performs
4810 these initializations itself.
4812 - CONFIG_SKIP_LOWLEVEL_INIT_ONLY
4813 [ARM926EJ-S only] This allows just the call to lowlevel_init()
4814 to be skipped. The normal CP15 init (such as enabling the
4815 instruction cache) is still performed.
4818 Modifies the behaviour of start.S when compiling a loader
4819 that is executed before the actual U-Boot. E.g. when
4820 compiling a NAND SPL.
4823 Modifies the behaviour of start.S when compiling a loader
4824 that is executed after the SPL and before the actual U-Boot.
4825 It is loaded by the SPL.
4827 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4828 Only for 85xx systems. If this variable is specified, the section
4829 .resetvec is not kept and the section .bootpg is placed in the
4830 previous 4k of the .text section.
4832 - CONFIG_ARCH_MAP_SYSMEM
4833 Generally U-Boot (and in particular the md command) uses
4834 effective address. It is therefore not necessary to regard
4835 U-Boot address as virtual addresses that need to be translated
4836 to physical addresses. However, sandbox requires this, since
4837 it maintains its own little RAM buffer which contains all
4838 addressable memory. This option causes some memory accesses
4839 to be mapped through map_sysmem() / unmap_sysmem().
4841 - CONFIG_USE_ARCH_MEMCPY
4842 CONFIG_USE_ARCH_MEMSET
4843 If these options are used a optimized version of memcpy/memset will
4844 be used if available. These functions may be faster under some
4845 conditions but may increase the binary size.
4847 - CONFIG_X86_RESET_VECTOR
4848 If defined, the x86 reset vector code is included. This is not
4849 needed when U-Boot is running from Coreboot.
4852 Defines the MPU clock speed (in MHz).
4854 NOTE : currently only supported on AM335x platforms.
4856 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4857 Enables the RTC32K OSC on AM33xx based plattforms
4859 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
4860 Option to disable subpage write in NAND driver
4861 driver that uses this:
4862 drivers/mtd/nand/davinci_nand.c
4864 Freescale QE/FMAN Firmware Support:
4865 -----------------------------------
4867 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4868 loading of "firmware", which is encoded in the QE firmware binary format.
4869 This firmware often needs to be loaded during U-Boot booting, so macros
4870 are used to identify the storage device (NOR flash, SPI, etc) and the address
4873 - CONFIG_SYS_FMAN_FW_ADDR
4874 The address in the storage device where the FMAN microcode is located. The
4875 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4878 - CONFIG_SYS_QE_FW_ADDR
4879 The address in the storage device where the QE microcode is located. The
4880 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4883 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4884 The maximum possible size of the firmware. The firmware binary format
4885 has a field that specifies the actual size of the firmware, but it
4886 might not be possible to read any part of the firmware unless some
4887 local storage is allocated to hold the entire firmware first.
4889 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4890 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4891 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4892 virtual address in NOR flash.
4894 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4895 Specifies that QE/FMAN firmware is located in NAND flash.
4896 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4898 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4899 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4900 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4902 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4903 Specifies that QE/FMAN firmware is located on the primary SPI
4904 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4906 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4907 Specifies that QE/FMAN firmware is located in the remote (master)
4908 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4909 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4910 window->master inbound window->master LAW->the ucode address in
4911 master's memory space.
4913 Freescale Layerscape Management Complex Firmware Support:
4914 ---------------------------------------------------------
4915 The Freescale Layerscape Management Complex (MC) supports the loading of
4917 This firmware often needs to be loaded during U-Boot booting, so macros
4918 are used to identify the storage device (NOR flash, SPI, etc) and the address
4921 - CONFIG_FSL_MC_ENET
4922 Enable the MC driver for Layerscape SoCs.
4924 - CONFIG_SYS_LS_MC_FW_ADDR
4925 The address in the storage device where the firmware is located. The
4926 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
4929 - CONFIG_SYS_LS_MC_FW_LENGTH
4930 The maximum possible size of the firmware. The firmware binary format
4931 has a field that specifies the actual size of the firmware, but it
4932 might not be possible to read any part of the firmware unless some
4933 local storage is allocated to hold the entire firmware first.
4935 - CONFIG_SYS_LS_MC_FW_IN_NOR
4936 Specifies that MC firmware is located in NOR flash, mapped as
4937 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
4938 virtual address in NOR flash.
4940 Freescale Layerscape Debug Server Support:
4941 -------------------------------------------
4942 The Freescale Layerscape Debug Server Support supports the loading of
4943 "Debug Server firmware" and triggering SP boot-rom.
4944 This firmware often needs to be loaded during U-Boot booting.
4946 - CONFIG_FSL_DEBUG_SERVER
4947 Enable the Debug Server for Layerscape SoCs.
4949 - CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE
4950 Define minimum DDR size required for debug server image
4952 - CONFIG_SYS_MC_RSV_MEM_ALIGN
4953 Define alignment of reserved memory MC requires
4958 In order to achieve reproducible builds, timestamps used in the U-Boot build
4959 process have to be set to a fixed value.
4961 This is done using the SOURCE_DATE_EPOCH environment variable.
4962 SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
4963 option for U-Boot or an environment variable in U-Boot.
4965 SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
4967 Building the Software:
4968 ======================
4970 Building U-Boot has been tested in several native build environments
4971 and in many different cross environments. Of course we cannot support
4972 all possibly existing versions of cross development tools in all
4973 (potentially obsolete) versions. In case of tool chain problems we
4974 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4975 which is extensively used to build and test U-Boot.
4977 If you are not using a native environment, it is assumed that you
4978 have GNU cross compiling tools available in your path. In this case,
4979 you must set the environment variable CROSS_COMPILE in your shell.
4980 Note that no changes to the Makefile or any other source files are
4981 necessary. For example using the ELDK on a 4xx CPU, please enter:
4983 $ CROSS_COMPILE=ppc_4xx-
4984 $ export CROSS_COMPILE
4986 Note: If you wish to generate Windows versions of the utilities in
4987 the tools directory you can use the MinGW toolchain
4988 (http://www.mingw.org). Set your HOST tools to the MinGW
4989 toolchain and execute 'make tools'. For example:
4991 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4993 Binaries such as tools/mkimage.exe will be created which can
4994 be executed on computers running Windows.
4996 U-Boot is intended to be simple to build. After installing the
4997 sources you must configure U-Boot for one specific board type. This
5002 where "NAME_defconfig" is the name of one of the existing configu-
5003 rations; see boards.cfg for supported names.
5005 Note: for some board special configuration names may exist; check if
5006 additional information is available from the board vendor; for
5007 instance, the TQM823L systems are available without (standard)
5008 or with LCD support. You can select such additional "features"
5009 when choosing the configuration, i. e.
5011 make TQM823L_defconfig
5012 - will configure for a plain TQM823L, i. e. no LCD support
5014 make TQM823L_LCD_defconfig
5015 - will configure for a TQM823L with U-Boot console on LCD
5020 Finally, type "make all", and you should get some working U-Boot
5021 images ready for download to / installation on your system:
5023 - "u-boot.bin" is a raw binary image
5024 - "u-boot" is an image in ELF binary format
5025 - "u-boot.srec" is in Motorola S-Record format
5027 By default the build is performed locally and the objects are saved
5028 in the source directory. One of the two methods can be used to change
5029 this behavior and build U-Boot to some external directory:
5031 1. Add O= to the make command line invocations:
5033 make O=/tmp/build distclean
5034 make O=/tmp/build NAME_defconfig
5035 make O=/tmp/build all
5037 2. Set environment variable KBUILD_OUTPUT to point to the desired location:
5039 export KBUILD_OUTPUT=/tmp/build
5044 Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
5048 Please be aware that the Makefiles assume you are using GNU make, so
5049 for instance on NetBSD you might need to use "gmake" instead of
5053 If the system board that you have is not listed, then you will need
5054 to port U-Boot to your hardware platform. To do this, follow these
5057 1. Create a new directory to hold your board specific code. Add any
5058 files you need. In your board directory, you will need at least
5059 the "Makefile" and a "<board>.c".
5060 2. Create a new configuration file "include/configs/<board>.h" for
5062 3. If you're porting U-Boot to a new CPU, then also create a new
5063 directory to hold your CPU specific code. Add any files you need.
5064 4. Run "make <board>_defconfig" with your new name.
5065 5. Type "make", and you should get a working "u-boot.srec" file
5066 to be installed on your target system.
5067 6. Debug and solve any problems that might arise.
5068 [Of course, this last step is much harder than it sounds.]
5071 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
5072 ==============================================================
5074 If you have modified U-Boot sources (for instance added a new board
5075 or support for new devices, a new CPU, etc.) you are expected to
5076 provide feedback to the other developers. The feedback normally takes
5077 the form of a "patch", i. e. a context diff against a certain (latest
5078 official or latest in the git repository) version of U-Boot sources.
5080 But before you submit such a patch, please verify that your modifi-
5081 cation did not break existing code. At least make sure that *ALL* of
5082 the supported boards compile WITHOUT ANY compiler warnings. To do so,
5083 just run the "MAKEALL" script, which will configure and build U-Boot
5084 for ALL supported system. Be warned, this will take a while. You can
5085 select which (cross) compiler to use by passing a `CROSS_COMPILE'
5086 environment variable to the script, i. e. to use the ELDK cross tools
5089 CROSS_COMPILE=ppc_8xx- MAKEALL
5091 or to build on a native PowerPC system you can type
5093 CROSS_COMPILE=' ' MAKEALL
5095 When using the MAKEALL script, the default behaviour is to build
5096 U-Boot in the source directory. This location can be changed by
5097 setting the BUILD_DIR environment variable. Also, for each target
5098 built, the MAKEALL script saves two log files (<target>.ERR and
5099 <target>.MAKEALL) in the <source dir>/LOG directory. This default
5100 location can be changed by setting the MAKEALL_LOGDIR environment
5101 variable. For example:
5103 export BUILD_DIR=/tmp/build
5104 export MAKEALL_LOGDIR=/tmp/log
5105 CROSS_COMPILE=ppc_8xx- MAKEALL
5107 With the above settings build objects are saved in the /tmp/build,
5108 log files are saved in the /tmp/log and the source tree remains clean
5109 during the whole build process.
5112 See also "U-Boot Porting Guide" below.
5115 Monitor Commands - Overview:
5116 ============================
5118 go - start application at address 'addr'
5119 run - run commands in an environment variable
5120 bootm - boot application image from memory
5121 bootp - boot image via network using BootP/TFTP protocol
5122 bootz - boot zImage from memory
5123 tftpboot- boot image via network using TFTP protocol
5124 and env variables "ipaddr" and "serverip"
5125 (and eventually "gatewayip")
5126 tftpput - upload a file via network using TFTP protocol
5127 rarpboot- boot image via network using RARP/TFTP protocol
5128 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
5129 loads - load S-Record file over serial line
5130 loadb - load binary file over serial line (kermit mode)
5132 mm - memory modify (auto-incrementing)
5133 nm - memory modify (constant address)
5134 mw - memory write (fill)
5136 cmp - memory compare
5137 crc32 - checksum calculation
5138 i2c - I2C sub-system
5139 sspi - SPI utility commands
5140 base - print or set address offset
5141 printenv- print environment variables
5142 setenv - set environment variables
5143 saveenv - save environment variables to persistent storage
5144 protect - enable or disable FLASH write protection
5145 erase - erase FLASH memory
5146 flinfo - print FLASH memory information
5147 nand - NAND memory operations (see doc/README.nand)
5148 bdinfo - print Board Info structure
5149 iminfo - print header information for application image
5150 coninfo - print console devices and informations
5151 ide - IDE sub-system
5152 loop - infinite loop on address range
5153 loopw - infinite write loop on address range
5154 mtest - simple RAM test
5155 icache - enable or disable instruction cache
5156 dcache - enable or disable data cache
5157 reset - Perform RESET of the CPU
5158 echo - echo args to console
5159 version - print monitor version
5160 help - print online help
5161 ? - alias for 'help'
5164 Monitor Commands - Detailed Description:
5165 ========================================
5169 For now: just type "help <command>".
5172 Environment Variables:
5173 ======================
5175 U-Boot supports user configuration using Environment Variables which
5176 can be made persistent by saving to Flash memory.
5178 Environment Variables are set using "setenv", printed using
5179 "printenv", and saved to Flash using "saveenv". Using "setenv"
5180 without a value can be used to delete a variable from the
5181 environment. As long as you don't save the environment you are
5182 working with an in-memory copy. In case the Flash area containing the
5183 environment is erased by accident, a default environment is provided.
5185 Some configuration options can be set using Environment Variables.
5187 List of environment variables (most likely not complete):
5189 baudrate - see CONFIG_BAUDRATE
5191 bootdelay - see CONFIG_BOOTDELAY
5193 bootcmd - see CONFIG_BOOTCOMMAND
5195 bootargs - Boot arguments when booting an RTOS image
5197 bootfile - Name of the image to load with TFTP
5199 bootm_low - Memory range available for image processing in the bootm
5200 command can be restricted. This variable is given as
5201 a hexadecimal number and defines lowest address allowed
5202 for use by the bootm command. See also "bootm_size"
5203 environment variable. Address defined by "bootm_low" is
5204 also the base of the initial memory mapping for the Linux
5205 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
5208 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
5209 This variable is given as a hexadecimal number and it
5210 defines the size of the memory region starting at base
5211 address bootm_low that is accessible by the Linux kernel
5212 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
5213 as the default value if it is defined, and bootm_size is
5216 bootm_size - Memory range available for image processing in the bootm
5217 command can be restricted. This variable is given as
5218 a hexadecimal number and defines the size of the region
5219 allowed for use by the bootm command. See also "bootm_low"
5220 environment variable.
5222 updatefile - Location of the software update file on a TFTP server, used
5223 by the automatic software update feature. Please refer to
5224 documentation in doc/README.update for more details.
5226 autoload - if set to "no" (any string beginning with 'n'),
5227 "bootp" will just load perform a lookup of the
5228 configuration from the BOOTP server, but not try to
5229 load any image using TFTP
5231 autostart - if set to "yes", an image loaded using the "bootp",
5232 "rarpboot", "tftpboot" or "diskboot" commands will
5233 be automatically started (by internally calling
5236 If set to "no", a standalone image passed to the
5237 "bootm" command will be copied to the load address
5238 (and eventually uncompressed), but NOT be started.
5239 This can be used to load and uncompress arbitrary
5242 fdt_high - if set this restricts the maximum address that the
5243 flattened device tree will be copied into upon boot.
5244 For example, if you have a system with 1 GB memory
5245 at physical address 0x10000000, while Linux kernel
5246 only recognizes the first 704 MB as low memory, you
5247 may need to set fdt_high as 0x3C000000 to have the
5248 device tree blob be copied to the maximum address
5249 of the 704 MB low memory, so that Linux kernel can
5250 access it during the boot procedure.
5252 If this is set to the special value 0xFFFFFFFF then
5253 the fdt will not be copied at all on boot. For this
5254 to work it must reside in writable memory, have
5255 sufficient padding on the end of it for u-boot to
5256 add the information it needs into it, and the memory
5257 must be accessible by the kernel.
5259 fdtcontroladdr- if set this is the address of the control flattened
5260 device tree used by U-Boot when CONFIG_OF_CONTROL is
5263 i2cfast - (PPC405GP|PPC405EP only)
5264 if set to 'y' configures Linux I2C driver for fast
5265 mode (400kHZ). This environment variable is used in
5266 initialization code. So, for changes to be effective
5267 it must be saved and board must be reset.
5269 initrd_high - restrict positioning of initrd images:
5270 If this variable is not set, initrd images will be
5271 copied to the highest possible address in RAM; this
5272 is usually what you want since it allows for
5273 maximum initrd size. If for some reason you want to
5274 make sure that the initrd image is loaded below the
5275 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
5276 variable to a value of "no" or "off" or "0".
5277 Alternatively, you can set it to a maximum upper
5278 address to use (U-Boot will still check that it
5279 does not overwrite the U-Boot stack and data).
5281 For instance, when you have a system with 16 MB
5282 RAM, and want to reserve 4 MB from use by Linux,
5283 you can do this by adding "mem=12M" to the value of
5284 the "bootargs" variable. However, now you must make
5285 sure that the initrd image is placed in the first
5286 12 MB as well - this can be done with
5288 setenv initrd_high 00c00000
5290 If you set initrd_high to 0xFFFFFFFF, this is an
5291 indication to U-Boot that all addresses are legal
5292 for the Linux kernel, including addresses in flash
5293 memory. In this case U-Boot will NOT COPY the
5294 ramdisk at all. This may be useful to reduce the
5295 boot time on your system, but requires that this
5296 feature is supported by your Linux kernel.
5298 ipaddr - IP address; needed for tftpboot command
5300 loadaddr - Default load address for commands like "bootp",
5301 "rarpboot", "tftpboot", "loadb" or "diskboot"
5303 loads_echo - see CONFIG_LOADS_ECHO
5305 serverip - TFTP server IP address; needed for tftpboot command
5307 bootretry - see CONFIG_BOOT_RETRY_TIME
5309 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
5311 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
5313 ethprime - controls which interface is used first.
5315 ethact - controls which interface is currently active.
5316 For example you can do the following
5318 => setenv ethact FEC
5319 => ping 192.168.0.1 # traffic sent on FEC
5320 => setenv ethact SCC
5321 => ping 10.0.0.1 # traffic sent on SCC
5323 ethrotate - When set to "no" U-Boot does not go through all
5324 available network interfaces.
5325 It just stays at the currently selected interface.
5327 netretry - When set to "no" each network operation will
5328 either succeed or fail without retrying.
5329 When set to "once" the network operation will
5330 fail when all the available network interfaces
5331 are tried once without success.
5332 Useful on scripts which control the retry operation
5335 npe_ucode - set load address for the NPE microcode
5337 silent_linux - If set then Linux will be told to boot silently, by
5338 changing the console to be empty. If "yes" it will be
5339 made silent. If "no" it will not be made silent. If
5340 unset, then it will be made silent if the U-Boot console
5343 tftpsrcp - If this is set, the value is used for TFTP's
5346 tftpdstp - If this is set, the value is used for TFTP's UDP
5347 destination port instead of the Well Know Port 69.
5349 tftpblocksize - Block size to use for TFTP transfers; if not set,
5350 we use the TFTP server's default block size
5352 tftptimeout - Retransmission timeout for TFTP packets (in milli-
5353 seconds, minimum value is 1000 = 1 second). Defines
5354 when a packet is considered to be lost so it has to
5355 be retransmitted. The default is 5000 = 5 seconds.
5356 Lowering this value may make downloads succeed
5357 faster in networks with high packet loss rates or
5358 with unreliable TFTP servers.
5360 tftptimeoutcountmax - maximum count of TFTP timeouts (no
5361 unit, minimum value = 0). Defines how many timeouts
5362 can happen during a single file transfer before that
5363 transfer is aborted. The default is 10, and 0 means
5364 'no timeouts allowed'. Increasing this value may help
5365 downloads succeed with high packet loss rates, or with
5366 unreliable TFTP servers or client hardware.
5368 vlan - When set to a value < 4095 the traffic over
5369 Ethernet is encapsulated/received over 802.1q
5372 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
5373 Unsigned value, in milliseconds. If not set, the period will
5374 be either the default (28000), or a value based on
5375 CONFIG_NET_RETRY_COUNT, if defined. This value has
5376 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
5378 The following image location variables contain the location of images
5379 used in booting. The "Image" column gives the role of the image and is
5380 not an environment variable name. The other columns are environment
5381 variable names. "File Name" gives the name of the file on a TFTP
5382 server, "RAM Address" gives the location in RAM the image will be
5383 loaded to, and "Flash Location" gives the image's address in NOR
5384 flash or offset in NAND flash.
5386 *Note* - these variables don't have to be defined for all boards, some
5387 boards currently use other variables for these purposes, and some
5388 boards use these variables for other purposes.
5390 Image File Name RAM Address Flash Location
5391 ----- --------- ----------- --------------
5392 u-boot u-boot u-boot_addr_r u-boot_addr
5393 Linux kernel bootfile kernel_addr_r kernel_addr
5394 device tree blob fdtfile fdt_addr_r fdt_addr
5395 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
5397 The following environment variables may be used and automatically
5398 updated by the network boot commands ("bootp" and "rarpboot"),
5399 depending the information provided by your boot server:
5401 bootfile - see above
5402 dnsip - IP address of your Domain Name Server
5403 dnsip2 - IP address of your secondary Domain Name Server
5404 gatewayip - IP address of the Gateway (Router) to use
5405 hostname - Target hostname
5407 netmask - Subnet Mask
5408 rootpath - Pathname of the root filesystem on the NFS server
5409 serverip - see above
5412 There are two special Environment Variables:
5414 serial# - contains hardware identification information such
5415 as type string and/or serial number
5416 ethaddr - Ethernet address
5418 These variables can be set only once (usually during manufacturing of
5419 the board). U-Boot refuses to delete or overwrite these variables
5420 once they have been set once.
5423 Further special Environment Variables:
5425 ver - Contains the U-Boot version string as printed
5426 with the "version" command. This variable is
5427 readonly (see CONFIG_VERSION_VARIABLE).
5430 Please note that changes to some configuration parameters may take
5431 only effect after the next boot (yes, that's just like Windoze :-).
5434 Callback functions for environment variables:
5435 ---------------------------------------------
5437 For some environment variables, the behavior of u-boot needs to change
5438 when their values are changed. This functionality allows functions to
5439 be associated with arbitrary variables. On creation, overwrite, or
5440 deletion, the callback will provide the opportunity for some side
5441 effect to happen or for the change to be rejected.
5443 The callbacks are named and associated with a function using the
5444 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5446 These callbacks are associated with variables in one of two ways. The
5447 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5448 in the board configuration to a string that defines a list of
5449 associations. The list must be in the following format:
5451 entry = variable_name[:callback_name]
5454 If the callback name is not specified, then the callback is deleted.
5455 Spaces are also allowed anywhere in the list.
5457 Callbacks can also be associated by defining the ".callbacks" variable
5458 with the same list format above. Any association in ".callbacks" will
5459 override any association in the static list. You can define
5460 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5461 ".callbacks" environment variable in the default or embedded environment.
5463 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
5464 regular expression. This allows multiple variables to be connected to
5465 the same callback without explicitly listing them all out.
5468 Command Line Parsing:
5469 =====================
5471 There are two different command line parsers available with U-Boot:
5472 the old "simple" one, and the much more powerful "hush" shell:
5474 Old, simple command line parser:
5475 --------------------------------
5477 - supports environment variables (through setenv / saveenv commands)
5478 - several commands on one line, separated by ';'
5479 - variable substitution using "... ${name} ..." syntax
5480 - special characters ('$', ';') can be escaped by prefixing with '\',
5482 setenv bootcmd bootm \${address}
5483 - You can also escape text by enclosing in single apostrophes, for example:
5484 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5489 - similar to Bourne shell, with control structures like
5490 if...then...else...fi, for...do...done; while...do...done,
5491 until...do...done, ...
5492 - supports environment ("global") variables (through setenv / saveenv
5493 commands) and local shell variables (through standard shell syntax
5494 "name=value"); only environment variables can be used with "run"
5500 (1) If a command line (or an environment variable executed by a "run"
5501 command) contains several commands separated by semicolon, and
5502 one of these commands fails, then the remaining commands will be
5505 (2) If you execute several variables with one call to run (i. e.
5506 calling run with a list of variables as arguments), any failing
5507 command will cause "run" to terminate, i. e. the remaining
5508 variables are not executed.
5510 Note for Redundant Ethernet Interfaces:
5511 =======================================
5513 Some boards come with redundant Ethernet interfaces; U-Boot supports
5514 such configurations and is capable of automatic selection of a
5515 "working" interface when needed. MAC assignment works as follows:
5517 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5518 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5519 "eth1addr" (=>eth1), "eth2addr", ...
5521 If the network interface stores some valid MAC address (for instance
5522 in SROM), this is used as default address if there is NO correspon-
5523 ding setting in the environment; if the corresponding environment
5524 variable is set, this overrides the settings in the card; that means:
5526 o If the SROM has a valid MAC address, and there is no address in the
5527 environment, the SROM's address is used.
5529 o If there is no valid address in the SROM, and a definition in the
5530 environment exists, then the value from the environment variable is
5533 o If both the SROM and the environment contain a MAC address, and
5534 both addresses are the same, this MAC address is used.
5536 o If both the SROM and the environment contain a MAC address, and the
5537 addresses differ, the value from the environment is used and a
5540 o If neither SROM nor the environment contain a MAC address, an error
5541 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
5542 a random, locally-assigned MAC is used.
5544 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5545 will be programmed into hardware as part of the initialization process. This
5546 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5547 The naming convention is as follows:
5548 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5553 U-Boot is capable of booting (and performing other auxiliary operations on)
5554 images in two formats:
5556 New uImage format (FIT)
5557 -----------------------
5559 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5560 to Flattened Device Tree). It allows the use of images with multiple
5561 components (several kernels, ramdisks, etc.), with contents protected by
5562 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5568 Old image format is based on binary files which can be basically anything,
5569 preceded by a special header; see the definitions in include/image.h for
5570 details; basically, the header defines the following image properties:
5572 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5573 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5574 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5575 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5577 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5578 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5579 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5580 * Compression Type (uncompressed, gzip, bzip2)
5586 The header is marked by a special Magic Number, and both the header
5587 and the data portions of the image are secured against corruption by
5594 Although U-Boot should support any OS or standalone application
5595 easily, the main focus has always been on Linux during the design of
5598 U-Boot includes many features that so far have been part of some
5599 special "boot loader" code within the Linux kernel. Also, any
5600 "initrd" images to be used are no longer part of one big Linux image;
5601 instead, kernel and "initrd" are separate images. This implementation
5602 serves several purposes:
5604 - the same features can be used for other OS or standalone
5605 applications (for instance: using compressed images to reduce the
5606 Flash memory footprint)
5608 - it becomes much easier to port new Linux kernel versions because
5609 lots of low-level, hardware dependent stuff are done by U-Boot
5611 - the same Linux kernel image can now be used with different "initrd"
5612 images; of course this also means that different kernel images can
5613 be run with the same "initrd". This makes testing easier (you don't
5614 have to build a new "zImage.initrd" Linux image when you just
5615 change a file in your "initrd"). Also, a field-upgrade of the
5616 software is easier now.
5622 Porting Linux to U-Boot based systems:
5623 ---------------------------------------
5625 U-Boot cannot save you from doing all the necessary modifications to
5626 configure the Linux device drivers for use with your target hardware
5627 (no, we don't intend to provide a full virtual machine interface to
5630 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5632 Just make sure your machine specific header file (for instance
5633 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5634 Information structure as we define in include/asm-<arch>/u-boot.h,
5635 and make sure that your definition of IMAP_ADDR uses the same value
5636 as your U-Boot configuration in CONFIG_SYS_IMMR.
5638 Note that U-Boot now has a driver model, a unified model for drivers.
5639 If you are adding a new driver, plumb it into driver model. If there
5640 is no uclass available, you are encouraged to create one. See
5644 Configuring the Linux kernel:
5645 -----------------------------
5647 No specific requirements for U-Boot. Make sure you have some root
5648 device (initial ramdisk, NFS) for your target system.
5651 Building a Linux Image:
5652 -----------------------
5654 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5655 not used. If you use recent kernel source, a new build target
5656 "uImage" will exist which automatically builds an image usable by
5657 U-Boot. Most older kernels also have support for a "pImage" target,
5658 which was introduced for our predecessor project PPCBoot and uses a
5659 100% compatible format.
5663 make TQM850L_defconfig
5668 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5669 encapsulate a compressed Linux kernel image with header information,
5670 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5672 * build a standard "vmlinux" kernel image (in ELF binary format):
5674 * convert the kernel into a raw binary image:
5676 ${CROSS_COMPILE}-objcopy -O binary \
5677 -R .note -R .comment \
5678 -S vmlinux linux.bin
5680 * compress the binary image:
5684 * package compressed binary image for U-Boot:
5686 mkimage -A ppc -O linux -T kernel -C gzip \
5687 -a 0 -e 0 -n "Linux Kernel Image" \
5688 -d linux.bin.gz uImage
5691 The "mkimage" tool can also be used to create ramdisk images for use
5692 with U-Boot, either separated from the Linux kernel image, or
5693 combined into one file. "mkimage" encapsulates the images with a 64
5694 byte header containing information about target architecture,
5695 operating system, image type, compression method, entry points, time
5696 stamp, CRC32 checksums, etc.
5698 "mkimage" can be called in two ways: to verify existing images and
5699 print the header information, or to build new images.
5701 In the first form (with "-l" option) mkimage lists the information
5702 contained in the header of an existing U-Boot image; this includes
5703 checksum verification:
5705 tools/mkimage -l image
5706 -l ==> list image header information
5708 The second form (with "-d" option) is used to build a U-Boot image
5709 from a "data file" which is used as image payload:
5711 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5712 -n name -d data_file image
5713 -A ==> set architecture to 'arch'
5714 -O ==> set operating system to 'os'
5715 -T ==> set image type to 'type'
5716 -C ==> set compression type 'comp'
5717 -a ==> set load address to 'addr' (hex)
5718 -e ==> set entry point to 'ep' (hex)
5719 -n ==> set image name to 'name'
5720 -d ==> use image data from 'datafile'
5722 Right now, all Linux kernels for PowerPC systems use the same load
5723 address (0x00000000), but the entry point address depends on the
5726 - 2.2.x kernels have the entry point at 0x0000000C,
5727 - 2.3.x and later kernels have the entry point at 0x00000000.
5729 So a typical call to build a U-Boot image would read:
5731 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5732 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5733 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5734 > examples/uImage.TQM850L
5735 Image Name: 2.4.4 kernel for TQM850L
5736 Created: Wed Jul 19 02:34:59 2000
5737 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5738 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5739 Load Address: 0x00000000
5740 Entry Point: 0x00000000
5742 To verify the contents of the image (or check for corruption):
5744 -> tools/mkimage -l examples/uImage.TQM850L
5745 Image Name: 2.4.4 kernel for TQM850L
5746 Created: Wed Jul 19 02:34:59 2000
5747 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5748 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5749 Load Address: 0x00000000
5750 Entry Point: 0x00000000
5752 NOTE: for embedded systems where boot time is critical you can trade
5753 speed for memory and install an UNCOMPRESSED image instead: this
5754 needs more space in Flash, but boots much faster since it does not
5755 need to be uncompressed:
5757 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5758 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5759 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5760 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5761 > examples/uImage.TQM850L-uncompressed
5762 Image Name: 2.4.4 kernel for TQM850L
5763 Created: Wed Jul 19 02:34:59 2000
5764 Image Type: PowerPC Linux Kernel Image (uncompressed)
5765 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5766 Load Address: 0x00000000
5767 Entry Point: 0x00000000
5770 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5771 when your kernel is intended to use an initial ramdisk:
5773 -> tools/mkimage -n 'Simple Ramdisk Image' \
5774 > -A ppc -O linux -T ramdisk -C gzip \
5775 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5776 Image Name: Simple Ramdisk Image
5777 Created: Wed Jan 12 14:01:50 2000
5778 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5779 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5780 Load Address: 0x00000000
5781 Entry Point: 0x00000000
5783 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5784 option performs the converse operation of the mkimage's second form (the "-d"
5785 option). Given an image built by mkimage, the dumpimage extracts a "data file"
5788 tools/dumpimage -i image -T type -p position data_file
5789 -i ==> extract from the 'image' a specific 'data_file'
5790 -T ==> set image type to 'type'
5791 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
5794 Installing a Linux Image:
5795 -------------------------
5797 To downloading a U-Boot image over the serial (console) interface,
5798 you must convert the image to S-Record format:
5800 objcopy -I binary -O srec examples/image examples/image.srec
5802 The 'objcopy' does not understand the information in the U-Boot
5803 image header, so the resulting S-Record file will be relative to
5804 address 0x00000000. To load it to a given address, you need to
5805 specify the target address as 'offset' parameter with the 'loads'
5808 Example: install the image to address 0x40100000 (which on the
5809 TQM8xxL is in the first Flash bank):
5811 => erase 40100000 401FFFFF
5817 ## Ready for S-Record download ...
5818 ~>examples/image.srec
5819 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5821 15989 15990 15991 15992
5822 [file transfer complete]
5824 ## Start Addr = 0x00000000
5827 You can check the success of the download using the 'iminfo' command;
5828 this includes a checksum verification so you can be sure no data
5829 corruption happened:
5833 ## Checking Image at 40100000 ...
5834 Image Name: 2.2.13 for initrd on TQM850L
5835 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5836 Data Size: 335725 Bytes = 327 kB = 0 MB
5837 Load Address: 00000000
5838 Entry Point: 0000000c
5839 Verifying Checksum ... OK
5845 The "bootm" command is used to boot an application that is stored in
5846 memory (RAM or Flash). In case of a Linux kernel image, the contents
5847 of the "bootargs" environment variable is passed to the kernel as
5848 parameters. You can check and modify this variable using the
5849 "printenv" and "setenv" commands:
5852 => printenv bootargs
5853 bootargs=root=/dev/ram
5855 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5857 => printenv bootargs
5858 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5861 ## Booting Linux kernel at 40020000 ...
5862 Image Name: 2.2.13 for NFS on TQM850L
5863 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5864 Data Size: 381681 Bytes = 372 kB = 0 MB
5865 Load Address: 00000000
5866 Entry Point: 0000000c
5867 Verifying Checksum ... OK
5868 Uncompressing Kernel Image ... OK
5869 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
5870 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5871 time_init: decrementer frequency = 187500000/60
5872 Calibrating delay loop... 49.77 BogoMIPS
5873 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5876 If you want to boot a Linux kernel with initial RAM disk, you pass
5877 the memory addresses of both the kernel and the initrd image (PPBCOOT
5878 format!) to the "bootm" command:
5880 => imi 40100000 40200000
5882 ## Checking Image at 40100000 ...
5883 Image Name: 2.2.13 for initrd on TQM850L
5884 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5885 Data Size: 335725 Bytes = 327 kB = 0 MB
5886 Load Address: 00000000
5887 Entry Point: 0000000c
5888 Verifying Checksum ... OK
5890 ## Checking Image at 40200000 ...
5891 Image Name: Simple Ramdisk Image
5892 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5893 Data Size: 566530 Bytes = 553 kB = 0 MB
5894 Load Address: 00000000
5895 Entry Point: 00000000
5896 Verifying Checksum ... OK
5898 => bootm 40100000 40200000
5899 ## Booting Linux kernel at 40100000 ...
5900 Image Name: 2.2.13 for initrd on TQM850L
5901 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5902 Data Size: 335725 Bytes = 327 kB = 0 MB
5903 Load Address: 00000000
5904 Entry Point: 0000000c
5905 Verifying Checksum ... OK
5906 Uncompressing Kernel Image ... OK
5907 ## Loading RAMDisk Image at 40200000 ...
5908 Image Name: Simple Ramdisk Image
5909 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5910 Data Size: 566530 Bytes = 553 kB = 0 MB
5911 Load Address: 00000000
5912 Entry Point: 00000000
5913 Verifying Checksum ... OK
5914 Loading Ramdisk ... OK
5915 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
5916 Boot arguments: root=/dev/ram
5917 time_init: decrementer frequency = 187500000/60
5918 Calibrating delay loop... 49.77 BogoMIPS
5920 RAMDISK: Compressed image found at block 0
5921 VFS: Mounted root (ext2 filesystem).
5925 Boot Linux and pass a flat device tree:
5928 First, U-Boot must be compiled with the appropriate defines. See the section
5929 titled "Linux Kernel Interface" above for a more in depth explanation. The
5930 following is an example of how to start a kernel and pass an updated
5936 oft=oftrees/mpc8540ads.dtb
5937 => tftp $oftaddr $oft
5938 Speed: 1000, full duplex
5940 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5941 Filename 'oftrees/mpc8540ads.dtb'.
5942 Load address: 0x300000
5945 Bytes transferred = 4106 (100a hex)
5946 => tftp $loadaddr $bootfile
5947 Speed: 1000, full duplex
5949 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5951 Load address: 0x200000
5952 Loading:############
5954 Bytes transferred = 1029407 (fb51f hex)
5959 => bootm $loadaddr - $oftaddr
5960 ## Booting image at 00200000 ...
5961 Image Name: Linux-2.6.17-dirty
5962 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5963 Data Size: 1029343 Bytes = 1005.2 kB
5964 Load Address: 00000000
5965 Entry Point: 00000000
5966 Verifying Checksum ... OK
5967 Uncompressing Kernel Image ... OK
5968 Booting using flat device tree at 0x300000
5969 Using MPC85xx ADS machine description
5970 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5974 More About U-Boot Image Types:
5975 ------------------------------
5977 U-Boot supports the following image types:
5979 "Standalone Programs" are directly runnable in the environment
5980 provided by U-Boot; it is expected that (if they behave
5981 well) you can continue to work in U-Boot after return from
5982 the Standalone Program.
5983 "OS Kernel Images" are usually images of some Embedded OS which
5984 will take over control completely. Usually these programs
5985 will install their own set of exception handlers, device
5986 drivers, set up the MMU, etc. - this means, that you cannot
5987 expect to re-enter U-Boot except by resetting the CPU.
5988 "RAMDisk Images" are more or less just data blocks, and their
5989 parameters (address, size) are passed to an OS kernel that is
5991 "Multi-File Images" contain several images, typically an OS
5992 (Linux) kernel image and one or more data images like
5993 RAMDisks. This construct is useful for instance when you want
5994 to boot over the network using BOOTP etc., where the boot
5995 server provides just a single image file, but you want to get
5996 for instance an OS kernel and a RAMDisk image.
5998 "Multi-File Images" start with a list of image sizes, each
5999 image size (in bytes) specified by an "uint32_t" in network
6000 byte order. This list is terminated by an "(uint32_t)0".
6001 Immediately after the terminating 0 follow the images, one by
6002 one, all aligned on "uint32_t" boundaries (size rounded up to
6003 a multiple of 4 bytes).
6005 "Firmware Images" are binary images containing firmware (like
6006 U-Boot or FPGA images) which usually will be programmed to
6009 "Script files" are command sequences that will be executed by
6010 U-Boot's command interpreter; this feature is especially
6011 useful when you configure U-Boot to use a real shell (hush)
6012 as command interpreter.
6014 Booting the Linux zImage:
6015 -------------------------
6017 On some platforms, it's possible to boot Linux zImage. This is done
6018 using the "bootz" command. The syntax of "bootz" command is the same
6019 as the syntax of "bootm" command.
6021 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
6022 kernel with raw initrd images. The syntax is slightly different, the
6023 address of the initrd must be augmented by it's size, in the following
6024 format: "<initrd addres>:<initrd size>".
6030 One of the features of U-Boot is that you can dynamically load and
6031 run "standalone" applications, which can use some resources of
6032 U-Boot like console I/O functions or interrupt services.
6034 Two simple examples are included with the sources:
6039 'examples/hello_world.c' contains a small "Hello World" Demo
6040 application; it is automatically compiled when you build U-Boot.
6041 It's configured to run at address 0x00040004, so you can play with it
6045 ## Ready for S-Record download ...
6046 ~>examples/hello_world.srec
6047 1 2 3 4 5 6 7 8 9 10 11 ...
6048 [file transfer complete]
6050 ## Start Addr = 0x00040004
6052 => go 40004 Hello World! This is a test.
6053 ## Starting application at 0x00040004 ...
6064 Hit any key to exit ...
6066 ## Application terminated, rc = 0x0
6068 Another example, which demonstrates how to register a CPM interrupt
6069 handler with the U-Boot code, can be found in 'examples/timer.c'.
6070 Here, a CPM timer is set up to generate an interrupt every second.
6071 The interrupt service routine is trivial, just printing a '.'
6072 character, but this is just a demo program. The application can be
6073 controlled by the following keys:
6075 ? - print current values og the CPM Timer registers
6076 b - enable interrupts and start timer
6077 e - stop timer and disable interrupts
6078 q - quit application
6081 ## Ready for S-Record download ...
6082 ~>examples/timer.srec
6083 1 2 3 4 5 6 7 8 9 10 11 ...
6084 [file transfer complete]
6086 ## Start Addr = 0x00040004
6089 ## Starting application at 0x00040004 ...
6092 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
6095 [q, b, e, ?] Set interval 1000000 us
6098 [q, b, e, ?] ........
6099 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
6102 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
6105 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
6108 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
6110 [q, b, e, ?] ...Stopping timer
6112 [q, b, e, ?] ## Application terminated, rc = 0x0
6118 Over time, many people have reported problems when trying to use the
6119 "minicom" terminal emulation program for serial download. I (wd)
6120 consider minicom to be broken, and recommend not to use it. Under
6121 Unix, I recommend to use C-Kermit for general purpose use (and
6122 especially for kermit binary protocol download ("loadb" command), and
6123 use "cu" for S-Record download ("loads" command). See
6124 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
6125 for help with kermit.
6128 Nevertheless, if you absolutely want to use it try adding this
6129 configuration to your "File transfer protocols" section:
6131 Name Program Name U/D FullScr IO-Red. Multi
6132 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
6133 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
6139 Starting at version 0.9.2, U-Boot supports NetBSD both as host
6140 (build U-Boot) and target system (boots NetBSD/mpc8xx).
6142 Building requires a cross environment; it is known to work on
6143 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
6144 need gmake since the Makefiles are not compatible with BSD make).
6145 Note that the cross-powerpc package does not install include files;
6146 attempting to build U-Boot will fail because <machine/ansi.h> is
6147 missing. This file has to be installed and patched manually:
6149 # cd /usr/pkg/cross/powerpc-netbsd/include
6151 # ln -s powerpc machine
6152 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
6153 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
6155 Native builds *don't* work due to incompatibilities between native
6156 and U-Boot include files.
6158 Booting assumes that (the first part of) the image booted is a
6159 stage-2 loader which in turn loads and then invokes the kernel
6160 proper. Loader sources will eventually appear in the NetBSD source
6161 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
6162 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
6165 Implementation Internals:
6166 =========================
6168 The following is not intended to be a complete description of every
6169 implementation detail. However, it should help to understand the
6170 inner workings of U-Boot and make it easier to port it to custom
6174 Initial Stack, Global Data:
6175 ---------------------------
6177 The implementation of U-Boot is complicated by the fact that U-Boot
6178 starts running out of ROM (flash memory), usually without access to
6179 system RAM (because the memory controller is not initialized yet).
6180 This means that we don't have writable Data or BSS segments, and BSS
6181 is not initialized as zero. To be able to get a C environment working
6182 at all, we have to allocate at least a minimal stack. Implementation
6183 options for this are defined and restricted by the CPU used: Some CPU
6184 models provide on-chip memory (like the IMMR area on MPC8xx and
6185 MPC826x processors), on others (parts of) the data cache can be
6186 locked as (mis-) used as memory, etc.
6188 Chris Hallinan posted a good summary of these issues to the
6189 U-Boot mailing list:
6191 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
6192 From: "Chris Hallinan" <clh@net1plus.com>
6193 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
6196 Correct me if I'm wrong, folks, but the way I understand it
6197 is this: Using DCACHE as initial RAM for Stack, etc, does not
6198 require any physical RAM backing up the cache. The cleverness
6199 is that the cache is being used as a temporary supply of
6200 necessary storage before the SDRAM controller is setup. It's
6201 beyond the scope of this list to explain the details, but you
6202 can see how this works by studying the cache architecture and
6203 operation in the architecture and processor-specific manuals.
6205 OCM is On Chip Memory, which I believe the 405GP has 4K. It
6206 is another option for the system designer to use as an
6207 initial stack/RAM area prior to SDRAM being available. Either
6208 option should work for you. Using CS 4 should be fine if your
6209 board designers haven't used it for something that would
6210 cause you grief during the initial boot! It is frequently not
6213 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
6214 with your processor/board/system design. The default value
6215 you will find in any recent u-boot distribution in
6216 walnut.h should work for you. I'd set it to a value larger
6217 than your SDRAM module. If you have a 64MB SDRAM module, set
6218 it above 400_0000. Just make sure your board has no resources
6219 that are supposed to respond to that address! That code in
6220 start.S has been around a while and should work as is when
6221 you get the config right.
6226 It is essential to remember this, since it has some impact on the C
6227 code for the initialization procedures:
6229 * Initialized global data (data segment) is read-only. Do not attempt
6232 * Do not use any uninitialized global data (or implicitly initialized
6233 as zero data - BSS segment) at all - this is undefined, initiali-
6234 zation is performed later (when relocating to RAM).
6236 * Stack space is very limited. Avoid big data buffers or things like
6239 Having only the stack as writable memory limits means we cannot use
6240 normal global data to share information between the code. But it
6241 turned out that the implementation of U-Boot can be greatly
6242 simplified by making a global data structure (gd_t) available to all
6243 functions. We could pass a pointer to this data as argument to _all_
6244 functions, but this would bloat the code. Instead we use a feature of
6245 the GCC compiler (Global Register Variables) to share the data: we
6246 place a pointer (gd) to the global data into a register which we
6247 reserve for this purpose.
6249 When choosing a register for such a purpose we are restricted by the
6250 relevant (E)ABI specifications for the current architecture, and by
6251 GCC's implementation.
6253 For PowerPC, the following registers have specific use:
6255 R2: reserved for system use
6256 R3-R4: parameter passing and return values
6257 R5-R10: parameter passing
6258 R13: small data area pointer
6262 (U-Boot also uses R12 as internal GOT pointer. r12
6263 is a volatile register so r12 needs to be reset when
6264 going back and forth between asm and C)
6266 ==> U-Boot will use R2 to hold a pointer to the global data
6268 Note: on PPC, we could use a static initializer (since the
6269 address of the global data structure is known at compile time),
6270 but it turned out that reserving a register results in somewhat
6271 smaller code - although the code savings are not that big (on
6272 average for all boards 752 bytes for the whole U-Boot image,
6273 624 text + 127 data).
6275 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
6276 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
6278 ==> U-Boot will use P3 to hold a pointer to the global data
6280 On ARM, the following registers are used:
6282 R0: function argument word/integer result
6283 R1-R3: function argument word
6284 R9: platform specific
6285 R10: stack limit (used only if stack checking is enabled)
6286 R11: argument (frame) pointer
6287 R12: temporary workspace
6290 R15: program counter
6292 ==> U-Boot will use R9 to hold a pointer to the global data
6294 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
6296 On Nios II, the ABI is documented here:
6297 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
6299 ==> U-Boot will use gp to hold a pointer to the global data
6301 Note: on Nios II, we give "-G0" option to gcc and don't use gp
6302 to access small data sections, so gp is free.
6304 On NDS32, the following registers are used:
6306 R0-R1: argument/return
6308 R15: temporary register for assembler
6309 R16: trampoline register
6310 R28: frame pointer (FP)
6311 R29: global pointer (GP)
6312 R30: link register (LP)
6313 R31: stack pointer (SP)
6314 PC: program counter (PC)
6316 ==> U-Boot will use R10 to hold a pointer to the global data
6318 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
6319 or current versions of GCC may "optimize" the code too much.
6324 U-Boot runs in system state and uses physical addresses, i.e. the
6325 MMU is not used either for address mapping nor for memory protection.
6327 The available memory is mapped to fixed addresses using the memory
6328 controller. In this process, a contiguous block is formed for each
6329 memory type (Flash, SDRAM, SRAM), even when it consists of several
6330 physical memory banks.
6332 U-Boot is installed in the first 128 kB of the first Flash bank (on
6333 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
6334 booting and sizing and initializing DRAM, the code relocates itself
6335 to the upper end of DRAM. Immediately below the U-Boot code some
6336 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
6337 configuration setting]. Below that, a structure with global Board
6338 Info data is placed, followed by the stack (growing downward).
6340 Additionally, some exception handler code is copied to the low 8 kB
6341 of DRAM (0x00000000 ... 0x00001FFF).
6343 So a typical memory configuration with 16 MB of DRAM could look like
6346 0x0000 0000 Exception Vector code
6349 0x0000 2000 Free for Application Use
6355 0x00FB FF20 Monitor Stack (Growing downward)
6356 0x00FB FFAC Board Info Data and permanent copy of global data
6357 0x00FC 0000 Malloc Arena
6360 0x00FE 0000 RAM Copy of Monitor Code
6361 ... eventually: LCD or video framebuffer
6362 ... eventually: pRAM (Protected RAM - unchanged by reset)
6363 0x00FF FFFF [End of RAM]
6366 System Initialization:
6367 ----------------------
6369 In the reset configuration, U-Boot starts at the reset entry point
6370 (on most PowerPC systems at address 0x00000100). Because of the reset
6371 configuration for CS0# this is a mirror of the on board Flash memory.
6372 To be able to re-map memory U-Boot then jumps to its link address.
6373 To be able to implement the initialization code in C, a (small!)
6374 initial stack is set up in the internal Dual Ported RAM (in case CPUs
6375 which provide such a feature like MPC8xx or MPC8260), or in a locked
6376 part of the data cache. After that, U-Boot initializes the CPU core,
6377 the caches and the SIU.
6379 Next, all (potentially) available memory banks are mapped using a
6380 preliminary mapping. For example, we put them on 512 MB boundaries
6381 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
6382 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
6383 programmed for SDRAM access. Using the temporary configuration, a
6384 simple memory test is run that determines the size of the SDRAM
6387 When there is more than one SDRAM bank, and the banks are of
6388 different size, the largest is mapped first. For equal size, the first
6389 bank (CS2#) is mapped first. The first mapping is always for address
6390 0x00000000, with any additional banks following immediately to create
6391 contiguous memory starting from 0.
6393 Then, the monitor installs itself at the upper end of the SDRAM area
6394 and allocates memory for use by malloc() and for the global Board
6395 Info data; also, the exception vector code is copied to the low RAM
6396 pages, and the final stack is set up.
6398 Only after this relocation will you have a "normal" C environment;
6399 until that you are restricted in several ways, mostly because you are
6400 running from ROM, and because the code will have to be relocated to a
6404 U-Boot Porting Guide:
6405 ----------------------
6407 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
6411 int main(int argc, char *argv[])
6413 sighandler_t no_more_time;
6415 signal(SIGALRM, no_more_time);
6416 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
6418 if (available_money > available_manpower) {
6419 Pay consultant to port U-Boot;
6423 Download latest U-Boot source;
6425 Subscribe to u-boot mailing list;
6428 email("Hi, I am new to U-Boot, how do I get started?");
6431 Read the README file in the top level directory;
6432 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6433 Read applicable doc/*.README;
6434 Read the source, Luke;
6435 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6438 if (available_money > toLocalCurrency ($2500))
6441 Add a lot of aggravation and time;
6443 if (a similar board exists) { /* hopefully... */
6444 cp -a board/<similar> board/<myboard>
6445 cp include/configs/<similar>.h include/configs/<myboard>.h
6447 Create your own board support subdirectory;
6448 Create your own board include/configs/<myboard>.h file;
6450 Edit new board/<myboard> files
6451 Edit new include/configs/<myboard>.h
6456 Add / modify source code;
6460 email("Hi, I am having problems...");
6462 Send patch file to the U-Boot email list;
6463 if (reasonable critiques)
6464 Incorporate improvements from email list code review;
6466 Defend code as written;
6472 void no_more_time (int sig)
6481 All contributions to U-Boot should conform to the Linux kernel
6482 coding style; see the file "Documentation/CodingStyle" and the script
6483 "scripts/Lindent" in your Linux kernel source directory.
6485 Source files originating from a different project (for example the
6486 MTD subsystem) are generally exempt from these guidelines and are not
6487 reformatted to ease subsequent migration to newer versions of those
6490 Please note that U-Boot is implemented in C (and to some small parts in
6491 Assembler); no C++ is used, so please do not use C++ style comments (//)
6494 Please also stick to the following formatting rules:
6495 - remove any trailing white space
6496 - use TAB characters for indentation and vertical alignment, not spaces
6497 - make sure NOT to use DOS '\r\n' line feeds
6498 - do not add more than 2 consecutive empty lines to source files
6499 - do not add trailing empty lines to source files
6501 Submissions which do not conform to the standards may be returned
6502 with a request to reformat the changes.
6508 Since the number of patches for U-Boot is growing, we need to
6509 establish some rules. Submissions which do not conform to these rules
6510 may be rejected, even when they contain important and valuable stuff.
6512 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6514 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
6515 see http://lists.denx.de/mailman/listinfo/u-boot
6517 When you send a patch, please include the following information with
6520 * For bug fixes: a description of the bug and how your patch fixes
6521 this bug. Please try to include a way of demonstrating that the
6522 patch actually fixes something.
6524 * For new features: a description of the feature and your
6527 * A CHANGELOG entry as plaintext (separate from the patch)
6529 * For major contributions, add a MAINTAINERS file with your
6530 information and associated file and directory references.
6532 * When you add support for a new board, don't forget to add a
6533 maintainer e-mail address to the boards.cfg file, too.
6535 * If your patch adds new configuration options, don't forget to
6536 document these in the README file.
6538 * The patch itself. If you are using git (which is *strongly*
6539 recommended) you can easily generate the patch using the
6540 "git format-patch". If you then use "git send-email" to send it to
6541 the U-Boot mailing list, you will avoid most of the common problems
6542 with some other mail clients.
6544 If you cannot use git, use "diff -purN OLD NEW". If your version of
6545 diff does not support these options, then get the latest version of
6548 The current directory when running this command shall be the parent
6549 directory of the U-Boot source tree (i. e. please make sure that
6550 your patch includes sufficient directory information for the
6553 We prefer patches as plain text. MIME attachments are discouraged,
6554 and compressed attachments must not be used.
6556 * If one logical set of modifications affects or creates several
6557 files, all these changes shall be submitted in a SINGLE patch file.
6559 * Changesets that contain different, unrelated modifications shall be
6560 submitted as SEPARATE patches, one patch per changeset.
6565 * Before sending the patch, run the MAKEALL script on your patched
6566 source tree and make sure that no errors or warnings are reported
6567 for any of the boards.
6569 * Keep your modifications to the necessary minimum: A patch
6570 containing several unrelated changes or arbitrary reformats will be
6571 returned with a request to re-formatting / split it.
6573 * If you modify existing code, make sure that your new code does not
6574 add to the memory footprint of the code ;-) Small is beautiful!
6575 When adding new features, these should compile conditionally only
6576 (using #ifdef), and the resulting code with the new feature
6577 disabled must not need more memory than the old code without your
6580 * Remember that there is a size limit of 100 kB per message on the
6581 u-boot mailing list. Bigger patches will be moderated. If they are
6582 reasonable and not too big, they will be acknowledged. But patches
6583 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob