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 and CREDITS files to find out
38 who contributed the specific port. The boards.cfg file lists board
41 Note: There is no CHANGELOG file in the actual U-Boot source tree;
42 it can be created dynamically from the Git log using:
50 In case you have questions about, problems with or contributions for
51 U-Boot you should send a message to the U-Boot mailing list at
52 <u-boot@lists.denx.de>. There is also an archive of previous traffic
53 on the mailing list - please search the archive before asking FAQ's.
54 Please see http://lists.denx.de/pipermail/u-boot and
55 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
58 Where to get source code:
59 =========================
61 The U-Boot source code is maintained in the git repository at
62 git://www.denx.de/git/u-boot.git ; you can browse it online at
63 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
65 The "snapshot" links on this page allow you to download tarballs of
66 any version you might be interested in. Official releases are also
67 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
70 Pre-built (and tested) images are available from
71 ftp://ftp.denx.de/pub/u-boot/images/
77 - start from 8xxrom sources
78 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
80 - make it easier to add custom boards
81 - make it possible to add other [PowerPC] CPUs
82 - extend functions, especially:
83 * Provide extended interface to Linux boot loader
86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
87 - create ARMBoot project (http://sourceforge.net/projects/armboot)
88 - add other CPU families (starting with ARM)
89 - create U-Boot project (http://sourceforge.net/projects/u-boot)
90 - current project page: see http://www.denx.de/wiki/U-Boot
96 The "official" name of this project is "Das U-Boot". The spelling
97 "U-Boot" shall be used in all written text (documentation, comments
98 in source files etc.). Example:
100 This is the README file for the U-Boot project.
102 File names etc. shall be based on the string "u-boot". Examples:
104 include/asm-ppc/u-boot.h
106 #include <asm/u-boot.h>
108 Variable names, preprocessor constants etc. shall be either based on
109 the string "u_boot" or on "U_BOOT". Example:
111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
118 Starting with the release in October 2008, the names of the releases
119 were changed from numerical release numbers without deeper meaning
120 into a time stamp based numbering. Regular releases are identified by
121 names consisting of the calendar year and month of the release date.
122 Additional fields (if present) indicate release candidates or bug fix
123 releases in "stable" maintenance trees.
126 U-Boot v2009.11 - Release November 2009
127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
134 /arch Architecture specific files
135 /arc Files generic to ARC architecture
136 /cpu CPU specific files
137 /arc700 Files specific to ARC 700 CPUs
138 /lib Architecture specific library files
139 /arm Files generic to ARM architecture
140 /cpu CPU specific files
141 /arm720t Files specific to ARM 720 CPUs
142 /arm920t Files specific to ARM 920 CPUs
143 /at91 Files specific to Atmel AT91RM9200 CPU
144 /imx Files specific to Freescale MC9328 i.MX CPUs
145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
146 /arm926ejs Files specific to ARM 926 CPUs
147 /arm1136 Files specific to ARM 1136 CPUs
148 /pxa Files specific to Intel XScale PXA CPUs
149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
150 /lib Architecture specific library files
151 /avr32 Files generic to AVR32 architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /blackfin Files generic to Analog Devices Blackfin architecture
155 /cpu CPU specific files
156 /lib Architecture specific library files
157 /m68k Files generic to m68k architecture
158 /cpu CPU specific files
159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 /lib Architecture specific library files
165 /microblaze Files generic to microblaze architecture
166 /cpu CPU specific files
167 /lib Architecture specific library files
168 /mips Files generic to MIPS architecture
169 /cpu CPU specific files
170 /mips32 Files specific to MIPS32 CPUs
171 /mips64 Files specific to MIPS64 CPUs
172 /lib Architecture specific library files
173 /nds32 Files generic to NDS32 architecture
174 /cpu CPU specific files
175 /n1213 Files specific to Andes Technology N1213 CPUs
176 /lib Architecture specific library files
177 /nios2 Files generic to Altera NIOS2 architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /openrisc Files generic to OpenRISC architecture
181 /cpu CPU specific files
182 /lib Architecture specific library files
183 /powerpc Files generic to PowerPC architecture
184 /cpu CPU specific files
185 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
186 /mpc5xx Files specific to Freescale MPC5xx CPUs
187 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
188 /mpc8xx Files specific to Freescale MPC8xx CPUs
189 /mpc824x Files specific to Freescale MPC824x CPUs
190 /mpc8260 Files specific to Freescale MPC8260 CPUs
191 /mpc85xx Files specific to Freescale MPC85xx CPUs
192 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
193 /lib Architecture specific library files
194 /sh Files generic to SH architecture
195 /cpu CPU specific files
196 /sh2 Files specific to sh2 CPUs
197 /sh3 Files specific to sh3 CPUs
198 /sh4 Files specific to sh4 CPUs
199 /lib Architecture specific library files
200 /sparc Files generic to SPARC architecture
201 /cpu CPU specific files
202 /leon2 Files specific to Gaisler LEON2 SPARC CPU
203 /leon3 Files specific to Gaisler LEON3 SPARC CPU
204 /lib Architecture specific library files
205 /x86 Files generic to x86 architecture
206 /cpu CPU specific files
207 /lib Architecture specific library files
208 /api Machine/arch independent API for external apps
209 /board Board dependent files
210 /common Misc architecture independent functions
211 /disk Code for disk drive partition handling
212 /doc Documentation (don't expect too much)
213 /drivers Commonly used device drivers
214 /dts Contains Makefile for building internal U-Boot fdt.
215 /examples Example code for standalone applications, etc.
216 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
217 /include Header Files
218 /lib Files generic to all architectures
219 /libfdt Library files to support flattened device trees
220 /lzma Library files to support LZMA decompression
221 /lzo Library files to support LZO decompression
223 /post Power On Self Test
224 /spl Secondary Program Loader framework
225 /tools Tools to build S-Record or U-Boot images, etc.
227 Software Configuration:
228 =======================
230 Configuration is usually done using C preprocessor defines; the
231 rationale behind that is to avoid dead code whenever possible.
233 There are two classes of configuration variables:
235 * Configuration _OPTIONS_:
236 These are selectable by the user and have names beginning with
239 * Configuration _SETTINGS_:
240 These depend on the hardware etc. and should not be meddled with if
241 you don't know what you're doing; they have names beginning with
244 Later we will add a configuration tool - probably similar to or even
245 identical to what's used for the Linux kernel. Right now, we have to
246 do the configuration by hand, which means creating some symbolic
247 links and editing some configuration files. We use the TQM8xxL boards
251 Selection of Processor Architecture and Board Type:
252 ---------------------------------------------------
254 For all supported boards there are ready-to-use default
255 configurations available; just type "make <board_name>_defconfig".
257 Example: For a TQM823L module type:
260 make TQM823L_defconfig
262 For the Cogent platform, you need to specify the CPU type as well;
263 e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent
264 directory according to the instructions in cogent/README.
270 U-Boot can be built natively to run on a Linux host using the 'sandbox'
271 board. This allows feature development which is not board- or architecture-
272 specific to be undertaken on a native platform. The sandbox is also used to
273 run some of U-Boot's tests.
275 See board/sandbox/README.sandbox for more details.
278 Configuration Options:
279 ----------------------
281 Configuration depends on the combination of board and CPU type; all
282 such information is kept in a configuration file
283 "include/configs/<board_name>.h".
285 Example: For a TQM823L module, all configuration settings are in
286 "include/configs/TQM823L.h".
289 Many of the options are named exactly as the corresponding Linux
290 kernel configuration options. The intention is to make it easier to
291 build a config tool - later.
294 The following options need to be configured:
296 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
298 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
300 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
301 Define exactly one, e.g. CONFIG_ATSTK1002
303 - CPU Module Type: (if CONFIG_COGENT is defined)
304 Define exactly one of
306 --- FIXME --- not tested yet:
307 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
308 CONFIG_CMA287_23, CONFIG_CMA287_50
310 - Motherboard Type: (if CONFIG_COGENT is defined)
311 Define exactly one of
312 CONFIG_CMA101, CONFIG_CMA102
314 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
315 Define one or more of
318 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
319 Define one or more of
320 CONFIG_LCD_HEARTBEAT - update a character position on
321 the LCD display every second with
324 - Marvell Family Member
325 CONFIG_SYS_MVFS - define it if you want to enable
326 multiple fs option at one time
327 for marvell soc family
329 - MPC824X Family Member (if CONFIG_MPC824X is defined)
330 Define exactly one of
331 CONFIG_MPC8240, CONFIG_MPC8245
333 - 8xx CPU Options: (if using an MPC8xx CPU)
334 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
335 get_gclk_freq() cannot work
336 e.g. if there is no 32KHz
337 reference PIT/RTC clock
338 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
341 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
342 CONFIG_SYS_8xx_CPUCLK_MIN
343 CONFIG_SYS_8xx_CPUCLK_MAX
344 CONFIG_8xx_CPUCLK_DEFAULT
345 See doc/README.MPC866
347 CONFIG_SYS_MEASURE_CPUCLK
349 Define this to measure the actual CPU clock instead
350 of relying on the correctness of the configured
351 values. Mostly useful for board bringup to make sure
352 the PLL is locked at the intended frequency. Note
353 that this requires a (stable) reference clock (32 kHz
354 RTC clock or CONFIG_SYS_8XX_XIN)
356 CONFIG_SYS_DELAYED_ICACHE
358 Define this option if you want to enable the
359 ICache only when Code runs from RAM.
364 Specifies that the core is a 64-bit PowerPC implementation (implements
365 the "64" category of the Power ISA). This is necessary for ePAPR
366 compliance, among other possible reasons.
368 CONFIG_SYS_FSL_TBCLK_DIV
370 Defines the core time base clock divider ratio compared to the
371 system clock. On most PQ3 devices this is 8, on newer QorIQ
372 devices it can be 16 or 32. The ratio varies from SoC to Soc.
374 CONFIG_SYS_FSL_PCIE_COMPAT
376 Defines the string to utilize when trying to match PCIe device
377 tree nodes for the given platform.
379 CONFIG_SYS_PPC_E500_DEBUG_TLB
381 Enables a temporary TLB entry to be used during boot to work
382 around limitations in e500v1 and e500v2 external debugger
383 support. This reduces the portions of the boot code where
384 breakpoints and single stepping do not work. The value of this
385 symbol should be set to the TLB1 entry to be used for this
388 CONFIG_SYS_FSL_ERRATUM_A004510
390 Enables a workaround for erratum A004510. If set,
391 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
392 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
394 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
395 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
397 Defines one or two SoC revisions (low 8 bits of SVR)
398 for which the A004510 workaround should be applied.
400 The rest of SVR is either not relevant to the decision
401 of whether the erratum is present (e.g. p2040 versus
402 p2041) or is implied by the build target, which controls
403 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
405 See Freescale App Note 4493 for more information about
408 CONFIG_A003399_NOR_WORKAROUND
409 Enables a workaround for IFC erratum A003399. It is only
410 requred during NOR boot.
412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
414 This is the value to write into CCSR offset 0x18600
415 according to the A004510 workaround.
417 CONFIG_SYS_FSL_DSP_DDR_ADDR
418 This value denotes start offset of DDR memory which is
419 connected exclusively to the DSP cores.
421 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
422 This value denotes start offset of M2 memory
423 which is directly connected to the DSP core.
425 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
426 This value denotes start offset of M3 memory which is directly
427 connected to the DSP core.
429 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
430 This value denotes start offset of DSP CCSR space.
432 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
433 Single Source Clock is clocking mode present in some of FSL SoC's.
434 In this mode, a single differential clock is used to supply
435 clocks to the sysclock, ddrclock and usbclock.
437 CONFIG_SYS_CPC_REINIT_F
438 This CONFIG is defined when the CPC is configured as SRAM at the
439 time of U-boot entry and is required to be re-initialized.
442 Inidcates this SoC supports deep sleep feature. If deep sleep is
443 supported, core will start to execute uboot when wakes up.
445 - Generic CPU options:
446 CONFIG_SYS_GENERIC_GLOBAL_DATA
447 Defines global data is initialized in generic board board_init_f().
448 If this macro is defined, global data is created and cleared in
449 generic board board_init_f(). Without this macro, architecture/board
450 should initialize global data before calling board_init_f().
452 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
454 Defines the endianess of the CPU. Implementation of those
455 values is arch specific.
458 Freescale DDR driver in use. This type of DDR controller is
459 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
462 CONFIG_SYS_FSL_DDR_ADDR
463 Freescale DDR memory-mapped register base.
465 CONFIG_SYS_FSL_DDR_EMU
466 Specify emulator support for DDR. Some DDR features such as
467 deskew training are not available.
469 CONFIG_SYS_FSL_DDRC_GEN1
470 Freescale DDR1 controller.
472 CONFIG_SYS_FSL_DDRC_GEN2
473 Freescale DDR2 controller.
475 CONFIG_SYS_FSL_DDRC_GEN3
476 Freescale DDR3 controller.
478 CONFIG_SYS_FSL_DDRC_GEN4
479 Freescale DDR4 controller.
481 CONFIG_SYS_FSL_DDRC_ARM_GEN3
482 Freescale DDR3 controller for ARM-based SoCs.
485 Board config to use DDR1. It can be enabled for SoCs with
486 Freescale DDR1 or DDR2 controllers, depending on the board
490 Board config to use DDR2. It can be eanbeld for SoCs with
491 Freescale DDR2 or DDR3 controllers, depending on the board
495 Board config to use DDR3. It can be enabled for SoCs with
496 Freescale DDR3 or DDR3L controllers.
499 Board config to use DDR3L. It can be enabled for SoCs with
503 Board config to use DDR4. It can be enabled for SoCs with
506 CONFIG_SYS_FSL_IFC_BE
507 Defines the IFC controller register space as Big Endian
509 CONFIG_SYS_FSL_IFC_LE
510 Defines the IFC controller register space as Little Endian
512 CONFIG_SYS_FSL_PBL_PBI
513 It enables addition of RCW (Power on reset configuration) in built image.
514 Please refer doc/README.pblimage for more details
516 CONFIG_SYS_FSL_PBL_RCW
517 It adds PBI(pre-boot instructions) commands in u-boot build image.
518 PBI commands can be used to configure SoC before it starts the execution.
519 Please refer doc/README.pblimage for more details
522 It adds a target to create boot binary having SPL binary in PBI format
523 concatenated with u-boot binary.
525 CONFIG_SYS_FSL_DDR_BE
526 Defines the DDR controller register space as Big Endian
528 CONFIG_SYS_FSL_DDR_LE
529 Defines the DDR controller register space as Little Endian
531 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
532 Physical address from the view of DDR controllers. It is the
533 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
534 it could be different for ARM SoCs.
536 CONFIG_SYS_FSL_DDR_INTLV_256B
537 DDR controller interleaving on 256-byte. This is a special
538 interleaving mode, handled by Dickens for Freescale layerscape
541 - Intel Monahans options:
542 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
544 Defines the Monahans run mode to oscillator
545 ratio. Valid values are 8, 16, 24, 31. The core
546 frequency is this value multiplied by 13 MHz.
548 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
550 Defines the Monahans turbo mode to oscillator
551 ratio. Valid values are 1 (default if undefined) and
552 2. The core frequency as calculated above is multiplied
556 CONFIG_SYS_INIT_SP_OFFSET
558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
559 pointer. This is needed for the temporary stack before
562 CONFIG_SYS_MIPS_CACHE_MODE
564 Cache operation mode for the MIPS CPU.
565 See also arch/mips/include/asm/mipsregs.h.
567 CONF_CM_CACHABLE_NO_WA
570 CONF_CM_CACHABLE_NONCOHERENT
574 CONF_CM_CACHABLE_ACCELERATED
576 CONFIG_SYS_XWAY_EBU_BOOTCFG
578 Special option for Lantiq XWAY SoCs for booting from NOR flash.
579 See also arch/mips/cpu/mips32/start.S.
581 CONFIG_XWAY_SWAP_BYTES
583 Enable compilation of tools/xway-swap-bytes needed for Lantiq
584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
585 be swapped if a flash programmer is used.
588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
590 Select high exception vectors of the ARM core, e.g., do not
591 clear the V bit of the c1 register of CP15.
593 CONFIG_SYS_THUMB_BUILD
595 Use this flag to build U-Boot using the Thumb instruction
596 set for ARM architectures. Thumb instruction set provides
597 better code density. For ARM architectures that support
598 Thumb2 this flag will result in Thumb2 code generated by
601 CONFIG_ARM_ERRATA_716044
602 CONFIG_ARM_ERRATA_742230
603 CONFIG_ARM_ERRATA_743622
604 CONFIG_ARM_ERRATA_751472
605 CONFIG_ARM_ERRATA_794072
606 CONFIG_ARM_ERRATA_761320
608 If set, the workarounds for these ARM errata are applied early
609 during U-Boot startup. Note that these options force the
610 workarounds to be applied; no CPU-type/version detection
611 exists, unlike the similar options in the Linux kernel. Do not
612 set these options unless they apply!
617 The frequency of the timer returned by get_timer().
618 get_timer() must operate in milliseconds and this CONFIG
619 option must be set to 1000.
621 - Linux Kernel Interface:
624 U-Boot stores all clock information in Hz
625 internally. For binary compatibility with older Linux
626 kernels (which expect the clocks passed in the
627 bd_info data to be in MHz) the environment variable
628 "clocks_in_mhz" can be defined so that U-Boot
629 converts clock data to MHZ before passing it to the
631 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
632 "clocks_in_mhz=1" is automatically included in the
635 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
637 When transferring memsize parameter to linux, some versions
638 expect it to be in bytes, others in MB.
639 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
643 New kernel versions are expecting firmware settings to be
644 passed using flattened device trees (based on open firmware
648 * New libfdt-based support
649 * Adds the "fdt" command
650 * The bootm command automatically updates the fdt
652 OF_CPU - The proper name of the cpus node (only required for
653 MPC512X and MPC5xxx based boards).
654 OF_SOC - The proper name of the soc node (only required for
655 MPC512X and MPC5xxx based boards).
656 OF_TBCLK - The timebase frequency.
657 OF_STDOUT_PATH - The path to the console device
659 boards with QUICC Engines require OF_QE to set UCC MAC
662 CONFIG_OF_BOARD_SETUP
664 Board code has addition modification that it wants to make
665 to the flat device tree before handing it off to the kernel
669 This define fills in the correct boot CPU in the boot
670 param header, the default value is zero if undefined.
674 U-Boot can detect if an IDE device is present or not.
675 If not, and this new config option is activated, U-Boot
676 removes the ATA node from the DTS before booting Linux,
677 so the Linux IDE driver does not probe the device and
678 crash. This is needed for buggy hardware (uc101) where
679 no pull down resistor is connected to the signal IDE5V_DD7.
681 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
683 This setting is mandatory for all boards that have only one
684 machine type and must be used to specify the machine type
685 number as it appears in the ARM machine registry
686 (see http://www.arm.linux.org.uk/developer/machines/).
687 Only boards that have multiple machine types supported
688 in a single configuration file and the machine type is
689 runtime discoverable, do not have to use this setting.
691 - vxWorks boot parameters:
693 bootvx constructs a valid bootline using the following
694 environments variables: bootfile, ipaddr, serverip, hostname.
695 It loads the vxWorks image pointed bootfile.
697 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
698 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
699 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
700 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
702 CONFIG_SYS_VXWORKS_ADD_PARAMS
704 Add it at the end of the bootline. E.g "u=username pw=secret"
706 Note: If a "bootargs" environment is defined, it will overwride
707 the defaults discussed just above.
709 - Cache Configuration:
710 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
711 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
712 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
714 - Cache Configuration for ARM:
715 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
717 CONFIG_SYS_PL310_BASE - Physical base address of PL310
718 controller register space
723 Define this if you want support for Amba PrimeCell PL010 UARTs.
727 Define this if you want support for Amba PrimeCell PL011 UARTs.
731 If you have Amba PrimeCell PL011 UARTs, set this variable to
732 the clock speed of the UARTs.
736 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
737 define this to a list of base addresses for each (supported)
738 port. See e.g. include/configs/versatile.h
740 CONFIG_PL011_SERIAL_RLCR
742 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
743 have separate receive and transmit line control registers. Set
744 this variable to initialize the extra register.
746 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
748 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
749 boot loader that has already initialized the UART. Define this
750 variable to flush the UART at init time.
752 CONFIG_SERIAL_HW_FLOW_CONTROL
754 Define this variable to enable hw flow control in serial driver.
755 Current user of this option is drivers/serial/nsl16550.c driver
758 Depending on board, define exactly one serial port
759 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
760 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
761 console by defining CONFIG_8xx_CONS_NONE
763 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
764 port routines must be defined elsewhere
765 (i.e. serial_init(), serial_getc(), ...)
768 Enables console device for a color framebuffer. Needs following
769 defines (cf. smiLynxEM, i8042)
770 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
772 VIDEO_HW_RECTFILL graphic chip supports
775 VIDEO_HW_BITBLT graphic chip supports
776 bit-blit (cf. smiLynxEM)
777 VIDEO_VISIBLE_COLS visible pixel columns
779 VIDEO_VISIBLE_ROWS visible pixel rows
780 VIDEO_PIXEL_SIZE bytes per pixel
781 VIDEO_DATA_FORMAT graphic data format
782 (0-5, cf. cfb_console.c)
783 VIDEO_FB_ADRS framebuffer address
784 VIDEO_KBD_INIT_FCT keyboard int fct
785 (i.e. i8042_kbd_init())
786 VIDEO_TSTC_FCT test char fct
788 VIDEO_GETC_FCT get char fct
790 CONFIG_CONSOLE_CURSOR cursor drawing on/off
791 (requires blink timer
793 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
794 CONFIG_CONSOLE_TIME display time/date info in
796 (requires CONFIG_CMD_DATE)
797 CONFIG_VIDEO_LOGO display Linux logo in
799 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
800 linux_logo.h for logo.
801 Requires CONFIG_VIDEO_LOGO
802 CONFIG_CONSOLE_EXTRA_INFO
803 additional board info beside
806 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
807 a limited number of ANSI escape sequences (cursor control,
808 erase functions and limited graphics rendition control).
810 When CONFIG_CFB_CONSOLE is defined, video console is
811 default i/o. Serial console can be forced with
812 environment 'console=serial'.
814 When CONFIG_SILENT_CONSOLE is defined, all console
815 messages (by U-Boot and Linux!) can be silenced with
816 the "silent" environment variable. See
817 doc/README.silent for more information.
819 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default
821 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default
825 CONFIG_BAUDRATE - in bps
826 Select one of the baudrates listed in
827 CONFIG_SYS_BAUDRATE_TABLE, see below.
828 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
830 - Console Rx buffer length
831 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
832 the maximum receive buffer length for the SMC.
833 This option is actual only for 82xx and 8xx possible.
834 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
835 must be defined, to setup the maximum idle timeout for
838 - Pre-Console Buffer:
839 Prior to the console being initialised (i.e. serial UART
840 initialised etc) all console output is silently discarded.
841 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
842 buffer any console messages prior to the console being
843 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
844 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
845 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
846 bytes are output before the console is initialised, the
847 earlier bytes are discarded.
849 'Sane' compilers will generate smaller code if
850 CONFIG_PRE_CON_BUF_SZ is a power of 2
852 - Safe printf() functions
853 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
854 the printf() functions. These are defined in
855 include/vsprintf.h and include snprintf(), vsnprintf() and
856 so on. Code size increase is approximately 300-500 bytes.
857 If this option is not given then these functions will
858 silently discard their buffer size argument - this means
859 you are not getting any overflow checking in this case.
861 - Boot Delay: CONFIG_BOOTDELAY - in seconds
862 Delay before automatically booting the default image;
863 set to -1 to disable autoboot.
864 set to -2 to autoboot with no delay and not check for abort
865 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
867 See doc/README.autoboot for these options that
868 work with CONFIG_BOOTDELAY. None are required.
869 CONFIG_BOOT_RETRY_TIME
870 CONFIG_BOOT_RETRY_MIN
871 CONFIG_AUTOBOOT_KEYED
872 CONFIG_AUTOBOOT_PROMPT
873 CONFIG_AUTOBOOT_DELAY_STR
874 CONFIG_AUTOBOOT_STOP_STR
875 CONFIG_AUTOBOOT_DELAY_STR2
876 CONFIG_AUTOBOOT_STOP_STR2
877 CONFIG_ZERO_BOOTDELAY_CHECK
878 CONFIG_RESET_TO_RETRY
882 Only needed when CONFIG_BOOTDELAY is enabled;
883 define a command string that is automatically executed
884 when no character is read on the console interface
885 within "Boot Delay" after reset.
888 This can be used to pass arguments to the bootm
889 command. The value of CONFIG_BOOTARGS goes into the
890 environment value "bootargs".
892 CONFIG_RAMBOOT and CONFIG_NFSBOOT
893 The value of these goes into the environment as
894 "ramboot" and "nfsboot" respectively, and can be used
895 as a convenience, when switching between booting from
899 CONFIG_BOOTCOUNT_LIMIT
900 Implements a mechanism for detecting a repeating reboot
902 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
905 If no softreset save registers are found on the hardware
906 "bootcount" is stored in the environment. To prevent a
907 saveenv on all reboots, the environment variable
908 "upgrade_available" is used. If "upgrade_available" is
909 0, "bootcount" is always 0, if "upgrade_available" is
910 1 "bootcount" is incremented in the environment.
911 So the Userspace Applikation must set the "upgrade_available"
912 and "bootcount" variable to 0, if a boot was successfully.
917 When this option is #defined, the existence of the
918 environment variable "preboot" will be checked
919 immediately before starting the CONFIG_BOOTDELAY
920 countdown and/or running the auto-boot command resp.
921 entering interactive mode.
923 This feature is especially useful when "preboot" is
924 automatically generated or modified. For an example
925 see the LWMON board specific code: here "preboot" is
926 modified when the user holds down a certain
927 combination of keys on the (special) keyboard when
930 - Serial Download Echo Mode:
932 If defined to 1, all characters received during a
933 serial download (using the "loads" command) are
934 echoed back. This might be needed by some terminal
935 emulations (like "cu"), but may as well just take
936 time on others. This setting #define's the initial
937 value of the "loads_echo" environment variable.
939 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
941 Select one of the baudrates listed in
942 CONFIG_SYS_BAUDRATE_TABLE, see below.
945 Monitor commands can be included or excluded
946 from the build by using the #include files
947 <config_cmd_all.h> and #undef'ing unwanted
948 commands, or using <config_cmd_default.h>
949 and augmenting with additional #define's
952 The default command configuration includes all commands
953 except those marked below with a "*".
955 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt
956 CONFIG_CMD_ASKENV * ask for env variable
957 CONFIG_CMD_BDI bdinfo
958 CONFIG_CMD_BEDBUG * Include BedBug Debugger
959 CONFIG_CMD_BMP * BMP support
960 CONFIG_CMD_BSP * Board specific commands
961 CONFIG_CMD_BOOTD bootd
962 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support
963 CONFIG_CMD_CACHE * icache, dcache
964 CONFIG_CMD_CLK * clock command support
965 CONFIG_CMD_CONSOLE coninfo
966 CONFIG_CMD_CRC32 * crc32
967 CONFIG_CMD_DATE * support for RTC, date/time...
968 CONFIG_CMD_DHCP * DHCP support
969 CONFIG_CMD_DIAG * Diagnostics
970 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
971 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
972 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
973 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
974 CONFIG_CMD_DTT * Digital Therm and Thermostat
975 CONFIG_CMD_ECHO echo arguments
976 CONFIG_CMD_EDITENV edit env variable
977 CONFIG_CMD_EEPROM * EEPROM read/write support
978 CONFIG_CMD_ELF * bootelf, bootvx
979 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
980 CONFIG_CMD_ENV_FLAGS * display details about env flags
981 CONFIG_CMD_ENV_EXISTS * check existence of env variable
982 CONFIG_CMD_EXPORTENV * export the environment
983 CONFIG_CMD_EXT2 * ext2 command support
984 CONFIG_CMD_EXT4 * ext4 command support
985 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls)
986 that work for multiple fs types
987 CONFIG_CMD_SAVEENV saveenv
988 CONFIG_CMD_FDC * Floppy Disk Support
989 CONFIG_CMD_FAT * FAT command support
990 CONFIG_CMD_FLASH flinfo, erase, protect
991 CONFIG_CMD_FPGA FPGA device initialization support
992 CONFIG_CMD_FUSE * Device fuse support
993 CONFIG_CMD_GETTIME * Get time since boot
994 CONFIG_CMD_GO * the 'go' command (exec code)
995 CONFIG_CMD_GREPENV * search environment
996 CONFIG_CMD_HASH * calculate hash / digest
997 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
998 CONFIG_CMD_I2C * I2C serial bus support
999 CONFIG_CMD_IDE * IDE harddisk support
1000 CONFIG_CMD_IMI iminfo
1001 CONFIG_CMD_IMLS List all images found in NOR flash
1002 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
1003 CONFIG_CMD_IMMAP * IMMR dump support
1004 CONFIG_CMD_IOTRACE * I/O tracing for debugging
1005 CONFIG_CMD_IMPORTENV * import an environment
1006 CONFIG_CMD_INI * import data from an ini file into the env
1007 CONFIG_CMD_IRQ * irqinfo
1008 CONFIG_CMD_ITEST Integer/string test of 2 values
1009 CONFIG_CMD_JFFS2 * JFFS2 Support
1010 CONFIG_CMD_KGDB * kgdb
1011 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
1012 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
1014 CONFIG_CMD_LOADB loadb
1015 CONFIG_CMD_LOADS loads
1016 CONFIG_CMD_MD5SUM * print md5 message digest
1017 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
1018 CONFIG_CMD_MEMINFO * Display detailed memory information
1019 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
1021 CONFIG_CMD_MEMTEST * mtest
1022 CONFIG_CMD_MISC Misc functions like sleep etc
1023 CONFIG_CMD_MMC * MMC memory mapped support
1024 CONFIG_CMD_MII * MII utility commands
1025 CONFIG_CMD_MTDPARTS * MTD partition support
1026 CONFIG_CMD_NAND * NAND support
1027 CONFIG_CMD_NET bootp, tftpboot, rarpboot
1028 CONFIG_CMD_NFS NFS support
1029 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
1030 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
1031 CONFIG_CMD_PCI * pciinfo
1032 CONFIG_CMD_PCMCIA * PCMCIA support
1033 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
1035 CONFIG_CMD_PORTIO * Port I/O
1036 CONFIG_CMD_READ * Read raw data from partition
1037 CONFIG_CMD_REGINFO * Register dump
1038 CONFIG_CMD_RUN run command in env variable
1039 CONFIG_CMD_SANDBOX * sb command to access sandbox features
1040 CONFIG_CMD_SAVES * save S record dump
1041 CONFIG_CMD_SCSI * SCSI Support
1042 CONFIG_CMD_SDRAM * print SDRAM configuration information
1043 (requires CONFIG_CMD_I2C)
1044 CONFIG_CMD_SETGETDCR Support for DCR Register access
1046 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
1047 CONFIG_CMD_SHA1SUM * print sha1 memory digest
1048 (requires CONFIG_CMD_MEMORY)
1049 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
1050 CONFIG_CMD_SOURCE "source" command Support
1051 CONFIG_CMD_SPI * SPI serial bus support
1052 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
1053 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
1054 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
1055 CONFIG_CMD_TIMER * access to the system tick timer
1056 CONFIG_CMD_USB * USB support
1057 CONFIG_CMD_CDP * Cisco Discover Protocol support
1058 CONFIG_CMD_MFSL * Microblaze FSL support
1059 CONFIG_CMD_XIMG Load part of Multi Image
1060 CONFIG_CMD_UUID * Generate random UUID or GUID string
1062 EXAMPLE: If you want all functions except of network
1063 support you can write:
1065 #include "config_cmd_all.h"
1066 #undef CONFIG_CMD_NET
1069 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
1071 Note: Don't enable the "icache" and "dcache" commands
1072 (configuration option CONFIG_CMD_CACHE) unless you know
1073 what you (and your U-Boot users) are doing. Data
1074 cache cannot be enabled on systems like the 8xx or
1075 8260 (where accesses to the IMMR region must be
1076 uncached), and it cannot be disabled on all other
1077 systems where we (mis-) use the data cache to hold an
1078 initial stack and some data.
1081 XXX - this list needs to get updated!
1083 - Regular expression support:
1085 If this variable is defined, U-Boot is linked against
1086 the SLRE (Super Light Regular Expression) library,
1087 which adds regex support to some commands, as for
1088 example "env grep" and "setexpr".
1092 If this variable is defined, U-Boot will use a device tree
1093 to configure its devices, instead of relying on statically
1094 compiled #defines in the board file. This option is
1095 experimental and only available on a few boards. The device
1096 tree is available in the global data as gd->fdt_blob.
1098 U-Boot needs to get its device tree from somewhere. This can
1099 be done using one of the two options below:
1102 If this variable is defined, U-Boot will embed a device tree
1103 binary in its image. This device tree file should be in the
1104 board directory and called <soc>-<board>.dts. The binary file
1105 is then picked up in board_init_f() and made available through
1106 the global data structure as gd->blob.
1109 If this variable is defined, U-Boot will build a device tree
1110 binary. It will be called u-boot.dtb. Architecture-specific
1111 code will locate it at run-time. Generally this works by:
1113 cat u-boot.bin u-boot.dtb >image.bin
1115 and in fact, U-Boot does this for you, creating a file called
1116 u-boot-dtb.bin which is useful in the common case. You can
1117 still use the individual files if you need something more
1122 If this variable is defined, it enables watchdog
1123 support for the SoC. There must be support in the SoC
1124 specific code for a watchdog. For the 8xx and 8260
1125 CPUs, the SIU Watchdog feature is enabled in the SYPCR
1126 register. When supported for a specific SoC is
1127 available, then no further board specific code should
1128 be needed to use it.
1131 When using a watchdog circuitry external to the used
1132 SoC, then define this variable and provide board
1133 specific code for the "hw_watchdog_reset" function.
1136 CONFIG_VERSION_VARIABLE
1137 If this variable is defined, an environment variable
1138 named "ver" is created by U-Boot showing the U-Boot
1139 version as printed by the "version" command.
1140 Any change to this variable will be reverted at the
1145 When CONFIG_CMD_DATE is selected, the type of the RTC
1146 has to be selected, too. Define exactly one of the
1149 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1150 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1151 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1152 CONFIG_RTC_MC146818 - use MC146818 RTC
1153 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1154 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1155 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1156 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
1157 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1158 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1159 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1160 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1161 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1164 Note that if the RTC uses I2C, then the I2C interface
1165 must also be configured. See I2C Support, below.
1168 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1170 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1171 chip-ngpio pairs that tell the PCA953X driver the number of
1172 pins supported by a particular chip.
1174 Note that if the GPIO device uses I2C, then the I2C interface
1175 must also be configured. See I2C Support, below.
1178 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
1179 accesses and can checksum them or write a list of them out
1180 to memory. See the 'iotrace' command for details. This is
1181 useful for testing device drivers since it can confirm that
1182 the driver behaves the same way before and after a code
1183 change. Currently this is supported on sandbox and arm. To
1184 add support for your architecture, add '#include <iotrace.h>'
1185 to the bottom of arch/<arch>/include/asm/io.h and test.
1187 Example output from the 'iotrace stats' command is below.
1188 Note that if the trace buffer is exhausted, the checksum will
1189 still continue to operate.
1192 Start: 10000000 (buffer start address)
1193 Size: 00010000 (buffer size)
1194 Offset: 00000120 (current buffer offset)
1195 Output: 10000120 (start + offset)
1196 Count: 00000018 (number of trace records)
1197 CRC32: 9526fb66 (CRC32 of all trace records)
1199 - Timestamp Support:
1201 When CONFIG_TIMESTAMP is selected, the timestamp
1202 (date and time) of an image is printed by image
1203 commands like bootm or iminfo. This option is
1204 automatically enabled when you select CONFIG_CMD_DATE .
1206 - Partition Labels (disklabels) Supported:
1207 Zero or more of the following:
1208 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1209 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1210 Intel architecture, USB sticks, etc.
1211 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1212 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1213 bootloader. Note 2TB partition limit; see
1215 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1217 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1218 CONFIG_CMD_SCSI) you must configure support for at
1219 least one non-MTD partition type as well.
1222 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1223 board configurations files but used nowhere!
1225 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1226 be performed by calling the function
1227 ide_set_reset(int reset)
1228 which has to be defined in a board specific file
1233 Set this to enable ATAPI support.
1238 Set this to enable support for disks larger than 137GB
1239 Also look at CONFIG_SYS_64BIT_LBA.
1240 Whithout these , LBA48 support uses 32bit variables and will 'only'
1241 support disks up to 2.1TB.
1243 CONFIG_SYS_64BIT_LBA:
1244 When enabled, makes the IDE subsystem use 64bit sector addresses.
1248 At the moment only there is only support for the
1249 SYM53C8XX SCSI controller; define
1250 CONFIG_SCSI_SYM53C8XX to enable it.
1252 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1253 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1254 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1255 maximum numbers of LUNs, SCSI ID's and target
1257 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1259 The environment variable 'scsidevs' is set to the number of
1260 SCSI devices found during the last scan.
1262 - NETWORK Support (PCI):
1264 Support for Intel 8254x/8257x gigabit chips.
1267 Utility code for direct access to the SPI bus on Intel 8257x.
1268 This does not do anything useful unless you set at least one
1269 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1271 CONFIG_E1000_SPI_GENERIC
1272 Allow generic access to the SPI bus on the Intel 8257x, for
1273 example with the "sspi" command.
1276 Management command for E1000 devices. When used on devices
1277 with SPI support you can reprogram the EEPROM from U-Boot.
1279 CONFIG_E1000_FALLBACK_MAC
1280 default MAC for empty EEPROM after production.
1283 Support for Intel 82557/82559/82559ER chips.
1284 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1285 write routine for first time initialisation.
1288 Support for Digital 2114x chips.
1289 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1290 modem chip initialisation (KS8761/QS6611).
1293 Support for National dp83815 chips.
1296 Support for National dp8382[01] gigabit chips.
1298 - NETWORK Support (other):
1300 CONFIG_DRIVER_AT91EMAC
1301 Support for AT91RM9200 EMAC.
1304 Define this to use reduced MII inteface
1306 CONFIG_DRIVER_AT91EMAC_QUIET
1307 If this defined, the driver is quiet.
1308 The driver doen't show link status messages.
1310 CONFIG_CALXEDA_XGMAC
1311 Support for the Calxeda XGMAC device
1314 Support for SMSC's LAN91C96 chips.
1316 CONFIG_LAN91C96_BASE
1317 Define this to hold the physical address
1318 of the LAN91C96's I/O space
1320 CONFIG_LAN91C96_USE_32_BIT
1321 Define this to enable 32 bit addressing
1324 Support for SMSC's LAN91C111 chip
1326 CONFIG_SMC91111_BASE
1327 Define this to hold the physical address
1328 of the device (I/O space)
1330 CONFIG_SMC_USE_32_BIT
1331 Define this if data bus is 32 bits
1333 CONFIG_SMC_USE_IOFUNCS
1334 Define this to use i/o functions instead of macros
1335 (some hardware wont work with macros)
1337 CONFIG_DRIVER_TI_EMAC
1338 Support for davinci emac
1340 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1341 Define this if you have more then 3 PHYs.
1344 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1346 CONFIG_FTGMAC100_EGIGA
1347 Define this to use GE link update with gigabit PHY.
1348 Define this if FTGMAC100 is connected to gigabit PHY.
1349 If your system has 10/100 PHY only, it might not occur
1350 wrong behavior. Because PHY usually return timeout or
1351 useless data when polling gigabit status and gigabit
1352 control registers. This behavior won't affect the
1353 correctnessof 10/100 link speed update.
1356 Support for SMSC's LAN911x and LAN921x chips
1359 Define this to hold the physical address
1360 of the device (I/O space)
1362 CONFIG_SMC911X_32_BIT
1363 Define this if data bus is 32 bits
1365 CONFIG_SMC911X_16_BIT
1366 Define this if data bus is 16 bits. If your processor
1367 automatically converts one 32 bit word to two 16 bit
1368 words you may also try CONFIG_SMC911X_32_BIT.
1371 Support for Renesas on-chip Ethernet controller
1373 CONFIG_SH_ETHER_USE_PORT
1374 Define the number of ports to be used
1376 CONFIG_SH_ETHER_PHY_ADDR
1377 Define the ETH PHY's address
1379 CONFIG_SH_ETHER_CACHE_WRITEBACK
1380 If this option is set, the driver enables cache flush.
1384 Support for PWM modul on the imx6.
1388 Support TPM devices.
1391 Support for i2c bus TPM devices. Only one device
1392 per system is supported at this time.
1394 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1395 Define the the i2c bus number for the TPM device
1397 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1398 Define the TPM's address on the i2c bus
1400 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1401 Define the burst count bytes upper limit
1403 CONFIG_TPM_ATMEL_TWI
1404 Support for Atmel TWI TPM device. Requires I2C support.
1407 Support for generic parallel port TPM devices. Only one device
1408 per system is supported at this time.
1410 CONFIG_TPM_TIS_BASE_ADDRESS
1411 Base address where the generic TPM device is mapped
1412 to. Contemporary x86 systems usually map it at
1416 Add tpm monitor functions.
1417 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1418 provides monitor access to authorized functions.
1421 Define this to enable the TPM support library which provides
1422 functional interfaces to some TPM commands.
1423 Requires support for a TPM device.
1425 CONFIG_TPM_AUTH_SESSIONS
1426 Define this to enable authorized functions in the TPM library.
1427 Requires CONFIG_TPM and CONFIG_SHA1.
1430 At the moment only the UHCI host controller is
1431 supported (PIP405, MIP405, MPC5200); define
1432 CONFIG_USB_UHCI to enable it.
1433 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1434 and define CONFIG_USB_STORAGE to enable the USB
1437 Supported are USB Keyboards and USB Floppy drives
1439 MPC5200 USB requires additional defines:
1441 for 528 MHz Clock: 0x0001bbbb
1445 for differential drivers: 0x00001000
1446 for single ended drivers: 0x00005000
1447 for differential drivers on PSC3: 0x00000100
1448 for single ended drivers on PSC3: 0x00004100
1449 CONFIG_SYS_USB_EVENT_POLL
1450 May be defined to allow interrupt polling
1451 instead of using asynchronous interrupts
1453 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1454 txfilltuning field in the EHCI controller on reset.
1457 Define the below if you wish to use the USB console.
1458 Once firmware is rebuilt from a serial console issue the
1459 command "setenv stdin usbtty; setenv stdout usbtty" and
1460 attach your USB cable. The Unix command "dmesg" should print
1461 it has found a new device. The environment variable usbtty
1462 can be set to gserial or cdc_acm to enable your device to
1463 appear to a USB host as a Linux gserial device or a
1464 Common Device Class Abstract Control Model serial device.
1465 If you select usbtty = gserial you should be able to enumerate
1467 # modprobe usbserial vendor=0xVendorID product=0xProductID
1468 else if using cdc_acm, simply setting the environment
1469 variable usbtty to be cdc_acm should suffice. The following
1470 might be defined in YourBoardName.h
1473 Define this to build a UDC device
1476 Define this to have a tty type of device available to
1477 talk to the UDC device
1480 Define this to enable the high speed support for usb
1481 device and usbtty. If this feature is enabled, a routine
1482 int is_usbd_high_speed(void)
1483 also needs to be defined by the driver to dynamically poll
1484 whether the enumeration has succeded at high speed or full
1487 CONFIG_SYS_CONSOLE_IS_IN_ENV
1488 Define this if you want stdin, stdout &/or stderr to
1492 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1493 Derive USB clock from external clock "blah"
1494 - CONFIG_SYS_USB_EXTC_CLK 0x02
1496 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1497 Derive USB clock from brgclk
1498 - CONFIG_SYS_USB_BRG_CLK 0x04
1500 If you have a USB-IF assigned VendorID then you may wish to
1501 define your own vendor specific values either in BoardName.h
1502 or directly in usbd_vendor_info.h. If you don't define
1503 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1504 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1505 should pretend to be a Linux device to it's target host.
1507 CONFIG_USBD_MANUFACTURER
1508 Define this string as the name of your company for
1509 - CONFIG_USBD_MANUFACTURER "my company"
1511 CONFIG_USBD_PRODUCT_NAME
1512 Define this string as the name of your product
1513 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1515 CONFIG_USBD_VENDORID
1516 Define this as your assigned Vendor ID from the USB
1517 Implementors Forum. This *must* be a genuine Vendor ID
1518 to avoid polluting the USB namespace.
1519 - CONFIG_USBD_VENDORID 0xFFFF
1521 CONFIG_USBD_PRODUCTID
1522 Define this as the unique Product ID
1524 - CONFIG_USBD_PRODUCTID 0xFFFF
1526 - ULPI Layer Support:
1527 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1528 the generic ULPI layer. The generic layer accesses the ULPI PHY
1529 via the platform viewport, so you need both the genric layer and
1530 the viewport enabled. Currently only Chipidea/ARC based
1531 viewport is supported.
1532 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1533 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1534 If your ULPI phy needs a different reference clock than the
1535 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1536 the appropriate value in Hz.
1539 The MMC controller on the Intel PXA is supported. To
1540 enable this define CONFIG_MMC. The MMC can be
1541 accessed from the boot prompt by mapping the device
1542 to physical memory similar to flash. Command line is
1543 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1544 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1547 Support for Renesas on-chip MMCIF controller
1549 CONFIG_SH_MMCIF_ADDR
1550 Define the base address of MMCIF registers
1553 Define the clock frequency for MMCIF
1556 Enable the generic MMC driver
1558 CONFIG_SUPPORT_EMMC_BOOT
1559 Enable some additional features of the eMMC boot partitions.
1561 CONFIG_SUPPORT_EMMC_RPMB
1562 Enable the commands for reading, writing and programming the
1563 key for the Replay Protection Memory Block partition in eMMC.
1565 - USB Device Firmware Update (DFU) class support:
1567 This enables the USB portion of the DFU USB class
1570 This enables the command "dfu" which is used to have
1571 U-Boot create a DFU class device via USB. This command
1572 requires that the "dfu_alt_info" environment variable be
1573 set and define the alt settings to expose to the host.
1576 This enables support for exposing (e)MMC devices via DFU.
1579 This enables support for exposing NAND devices via DFU.
1582 This enables support for exposing RAM via DFU.
1583 Note: DFU spec refer to non-volatile memory usage, but
1584 allow usages beyond the scope of spec - here RAM usage,
1585 one that would help mostly the developer.
1587 CONFIG_SYS_DFU_DATA_BUF_SIZE
1588 Dfu transfer uses a buffer before writing data to the
1589 raw storage device. Make the size (in bytes) of this buffer
1590 configurable. The size of this buffer is also configurable
1591 through the "dfu_bufsiz" environment variable.
1593 CONFIG_SYS_DFU_MAX_FILE_SIZE
1594 When updating files rather than the raw storage device,
1595 we use a static buffer to copy the file into and then write
1596 the buffer once we've been given the whole file. Define
1597 this to the maximum filesize (in bytes) for the buffer.
1598 Default is 4 MiB if undefined.
1600 DFU_DEFAULT_POLL_TIMEOUT
1601 Poll timeout [ms], is the timeout a device can send to the
1602 host. The host must wait for this timeout before sending
1603 a subsequent DFU_GET_STATUS request to the device.
1605 DFU_MANIFEST_POLL_TIMEOUT
1606 Poll timeout [ms], which the device sends to the host when
1607 entering dfuMANIFEST state. Host waits this timeout, before
1608 sending again an USB request to the device.
1610 - USB Device Android Fastboot support:
1612 This enables the command "fastboot" which enables the Android
1613 fastboot mode for the platform's USB device. Fastboot is a USB
1614 protocol for downloading images, flashing and device control
1615 used on Android devices.
1616 See doc/README.android-fastboot for more information.
1618 CONFIG_ANDROID_BOOT_IMAGE
1619 This enables support for booting images which use the Android
1620 image format header.
1622 CONFIG_USB_FASTBOOT_BUF_ADDR
1623 The fastboot protocol requires a large memory buffer for
1624 downloads. Define this to the starting RAM address to use for
1627 CONFIG_USB_FASTBOOT_BUF_SIZE
1628 The fastboot protocol requires a large memory buffer for
1629 downloads. This buffer should be as large as possible for a
1630 platform. Define this to the size available RAM for fastboot.
1632 CONFIG_FASTBOOT_FLASH
1633 The fastboot protocol includes a "flash" command for writing
1634 the downloaded image to a non-volatile storage device. Define
1635 this to enable the "fastboot flash" command.
1637 CONFIG_FASTBOOT_FLASH_MMC_DEV
1638 The fastboot "flash" command requires additional information
1639 regarding the non-volatile storage device. Define this to
1640 the eMMC device that fastboot should use to store the image.
1642 - Journaling Flash filesystem support:
1643 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1644 CONFIG_JFFS2_NAND_DEV
1645 Define these for a default partition on a NAND device
1647 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1648 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1649 Define these for a default partition on a NOR device
1651 CONFIG_SYS_JFFS_CUSTOM_PART
1652 Define this to create an own partition. You have to provide a
1653 function struct part_info* jffs2_part_info(int part_num)
1655 If you define only one JFFS2 partition you may also want to
1656 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1657 to disable the command chpart. This is the default when you
1658 have not defined a custom partition
1660 - FAT(File Allocation Table) filesystem write function support:
1663 Define this to enable support for saving memory data as a
1664 file in FAT formatted partition.
1666 This will also enable the command "fatwrite" enabling the
1667 user to write files to FAT.
1669 CBFS (Coreboot Filesystem) support
1672 Define this to enable support for reading from a Coreboot
1673 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1676 - FAT(File Allocation Table) filesystem cluster size:
1677 CONFIG_FS_FAT_MAX_CLUSTSIZE
1679 Define the max cluster size for fat operations else
1680 a default value of 65536 will be defined.
1685 Define this to enable standard (PC-Style) keyboard
1689 Standard PC keyboard driver with US (is default) and
1690 GERMAN key layout (switch via environment 'keymap=de') support.
1691 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1692 for cfb_console. Supports cursor blinking.
1695 Enables a Chrome OS keyboard using the CROS_EC interface.
1696 This uses CROS_EC to communicate with a second microcontroller
1697 which provides key scans on request.
1702 Define this to enable video support (for output to
1705 CONFIG_VIDEO_CT69000
1707 Enable Chips & Technologies 69000 Video chip
1709 CONFIG_VIDEO_SMI_LYNXEM
1710 Enable Silicon Motion SMI 712/710/810 Video chip. The
1711 video output is selected via environment 'videoout'
1712 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1715 For the CT69000 and SMI_LYNXEM drivers, videomode is
1716 selected via environment 'videomode'. Two different ways
1718 - "videomode=num" 'num' is a standard LiLo mode numbers.
1719 Following standard modes are supported (* is default):
1721 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1722 -------------+---------------------------------------------
1723 8 bits | 0x301* 0x303 0x305 0x161 0x307
1724 15 bits | 0x310 0x313 0x316 0x162 0x319
1725 16 bits | 0x311 0x314 0x317 0x163 0x31A
1726 24 bits | 0x312 0x315 0x318 ? 0x31B
1727 -------------+---------------------------------------------
1728 (i.e. setenv videomode 317; saveenv; reset;)
1730 - "videomode=bootargs" all the video parameters are parsed
1731 from the bootargs. (See drivers/video/videomodes.c)
1734 CONFIG_VIDEO_SED13806
1735 Enable Epson SED13806 driver. This driver supports 8bpp
1736 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1737 or CONFIG_VIDEO_SED13806_16BPP
1740 Enable the Freescale DIU video driver. Reference boards for
1741 SOCs that have a DIU should define this macro to enable DIU
1742 support, and should also define these other macros:
1748 CONFIG_VIDEO_SW_CURSOR
1749 CONFIG_VGA_AS_SINGLE_DEVICE
1751 CONFIG_VIDEO_BMP_LOGO
1753 The DIU driver will look for the 'video-mode' environment
1754 variable, and if defined, enable the DIU as a console during
1755 boot. See the documentation file README.video for a
1756 description of this variable.
1760 Enable the VGA video / BIOS for x86. The alternative if you
1761 are using coreboot is to use the coreboot frame buffer
1768 Define this to enable a custom keyboard support.
1769 This simply calls drv_keyboard_init() which must be
1770 defined in your board-specific files.
1771 The only board using this so far is RBC823.
1773 - LCD Support: CONFIG_LCD
1775 Define this to enable LCD support (for output to LCD
1776 display); also select one of the supported displays
1777 by defining one of these:
1781 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1783 CONFIG_NEC_NL6448AC33:
1785 NEC NL6448AC33-18. Active, color, single scan.
1787 CONFIG_NEC_NL6448BC20
1789 NEC NL6448BC20-08. 6.5", 640x480.
1790 Active, color, single scan.
1792 CONFIG_NEC_NL6448BC33_54
1794 NEC NL6448BC33-54. 10.4", 640x480.
1795 Active, color, single scan.
1799 Sharp 320x240. Active, color, single scan.
1800 It isn't 16x9, and I am not sure what it is.
1802 CONFIG_SHARP_LQ64D341
1804 Sharp LQ64D341 display, 640x480.
1805 Active, color, single scan.
1809 HLD1045 display, 640x480.
1810 Active, color, single scan.
1814 Optrex CBL50840-2 NF-FW 99 22 M5
1816 Hitachi LMG6912RPFC-00T
1820 320x240. Black & white.
1822 Normally display is black on white background; define
1823 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1825 CONFIG_LCD_ALIGNMENT
1827 Normally the LCD is page-aligned (tyically 4KB). If this is
1828 defined then the LCD will be aligned to this value instead.
1829 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1830 here, since it is cheaper to change data cache settings on
1831 a per-section basis.
1833 CONFIG_CONSOLE_SCROLL_LINES
1835 When the console need to be scrolled, this is the number of
1836 lines to scroll by. It defaults to 1. Increasing this makes
1837 the console jump but can help speed up operation when scrolling
1842 Support drawing of RLE8-compressed bitmaps on the LCD.
1846 Enables an 'i2c edid' command which can read EDID
1847 information over I2C from an attached LCD display.
1849 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1851 If this option is set, the environment is checked for
1852 a variable "splashimage". If found, the usual display
1853 of logo, copyright and system information on the LCD
1854 is suppressed and the BMP image at the address
1855 specified in "splashimage" is loaded instead. The
1856 console is redirected to the "nulldev", too. This
1857 allows for a "silent" boot where a splash screen is
1858 loaded very quickly after power-on.
1860 CONFIG_SPLASHIMAGE_GUARD
1862 If this option is set, then U-Boot will prevent the environment
1863 variable "splashimage" from being set to a problematic address
1864 (see README.displaying-bmps).
1865 This option is useful for targets where, due to alignment
1866 restrictions, an improperly aligned BMP image will cause a data
1867 abort. If you think you will not have problems with unaligned
1868 accesses (for example because your toolchain prevents them)
1869 there is no need to set this option.
1871 CONFIG_SPLASH_SCREEN_ALIGN
1873 If this option is set the splash image can be freely positioned
1874 on the screen. Environment variable "splashpos" specifies the
1875 position as "x,y". If a positive number is given it is used as
1876 number of pixel from left/top. If a negative number is given it
1877 is used as number of pixel from right/bottom. You can also
1878 specify 'm' for centering the image.
1881 setenv splashpos m,m
1882 => image at center of screen
1884 setenv splashpos 30,20
1885 => image at x = 30 and y = 20
1887 setenv splashpos -10,m
1888 => vertically centered image
1889 at x = dspWidth - bmpWidth - 9
1891 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1893 If this option is set, additionally to standard BMP
1894 images, gzipped BMP images can be displayed via the
1895 splashscreen support or the bmp command.
1897 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1899 If this option is set, 8-bit RLE compressed BMP images
1900 can be displayed via the splashscreen support or the
1903 - Do compresssing for memory range:
1906 If this option is set, it would use zlib deflate method
1907 to compress the specified memory at its best effort.
1909 - Compression support:
1912 Enabled by default to support gzip compressed images.
1916 If this option is set, support for bzip2 compressed
1917 images is included. If not, only uncompressed and gzip
1918 compressed images are supported.
1920 NOTE: the bzip2 algorithm requires a lot of RAM, so
1921 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1926 If this option is set, support for lzma compressed
1929 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1930 requires an amount of dynamic memory that is given by the
1933 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1935 Where lc and lp stand for, respectively, Literal context bits
1936 and Literal pos bits.
1938 This value is upper-bounded by 14MB in the worst case. Anyway,
1939 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1940 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1941 a very small buffer.
1943 Use the lzmainfo tool to determinate the lc and lp values and
1944 then calculate the amount of needed dynamic memory (ensuring
1945 the appropriate CONFIG_SYS_MALLOC_LEN value).
1949 If this option is set, support for LZO compressed images
1955 The address of PHY on MII bus.
1957 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1959 The clock frequency of the MII bus
1963 If this option is set, support for speed/duplex
1964 detection of gigabit PHY is included.
1966 CONFIG_PHY_RESET_DELAY
1968 Some PHY like Intel LXT971A need extra delay after
1969 reset before any MII register access is possible.
1970 For such PHY, set this option to the usec delay
1971 required. (minimum 300usec for LXT971A)
1973 CONFIG_PHY_CMD_DELAY (ppc4xx)
1975 Some PHY like Intel LXT971A need extra delay after
1976 command issued before MII status register can be read
1986 Define a default value for Ethernet address to use
1987 for the respective Ethernet interface, in case this
1988 is not determined automatically.
1993 Define a default value for the IP address to use for
1994 the default Ethernet interface, in case this is not
1995 determined through e.g. bootp.
1996 (Environment variable "ipaddr")
1998 - Server IP address:
2001 Defines a default value for the IP address of a TFTP
2002 server to contact when using the "tftboot" command.
2003 (Environment variable "serverip")
2005 CONFIG_KEEP_SERVERADDR
2007 Keeps the server's MAC address, in the env 'serveraddr'
2008 for passing to bootargs (like Linux's netconsole option)
2010 - Gateway IP address:
2013 Defines a default value for the IP address of the
2014 default router where packets to other networks are
2016 (Environment variable "gatewayip")
2021 Defines a default value for the subnet mask (or
2022 routing prefix) which is used to determine if an IP
2023 address belongs to the local subnet or needs to be
2024 forwarded through a router.
2025 (Environment variable "netmask")
2027 - Multicast TFTP Mode:
2030 Defines whether you want to support multicast TFTP as per
2031 rfc-2090; for example to work with atftp. Lets lots of targets
2032 tftp down the same boot image concurrently. Note: the Ethernet
2033 driver in use must provide a function: mcast() to join/leave a
2036 - BOOTP Recovery Mode:
2037 CONFIG_BOOTP_RANDOM_DELAY
2039 If you have many targets in a network that try to
2040 boot using BOOTP, you may want to avoid that all
2041 systems send out BOOTP requests at precisely the same
2042 moment (which would happen for instance at recovery
2043 from a power failure, when all systems will try to
2044 boot, thus flooding the BOOTP server. Defining
2045 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
2046 inserted before sending out BOOTP requests. The
2047 following delays are inserted then:
2049 1st BOOTP request: delay 0 ... 1 sec
2050 2nd BOOTP request: delay 0 ... 2 sec
2051 3rd BOOTP request: delay 0 ... 4 sec
2053 BOOTP requests: delay 0 ... 8 sec
2055 CONFIG_BOOTP_ID_CACHE_SIZE
2057 BOOTP packets are uniquely identified using a 32-bit ID. The
2058 server will copy the ID from client requests to responses and
2059 U-Boot will use this to determine if it is the destination of
2060 an incoming response. Some servers will check that addresses
2061 aren't in use before handing them out (usually using an ARP
2062 ping) and therefore take up to a few hundred milliseconds to
2063 respond. Network congestion may also influence the time it
2064 takes for a response to make it back to the client. If that
2065 time is too long, U-Boot will retransmit requests. In order
2066 to allow earlier responses to still be accepted after these
2067 retransmissions, U-Boot's BOOTP client keeps a small cache of
2068 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
2069 cache. The default is to keep IDs for up to four outstanding
2070 requests. Increasing this will allow U-Boot to accept offers
2071 from a BOOTP client in networks with unusually high latency.
2073 - DHCP Advanced Options:
2074 You can fine tune the DHCP functionality by defining
2075 CONFIG_BOOTP_* symbols:
2077 CONFIG_BOOTP_SUBNETMASK
2078 CONFIG_BOOTP_GATEWAY
2079 CONFIG_BOOTP_HOSTNAME
2080 CONFIG_BOOTP_NISDOMAIN
2081 CONFIG_BOOTP_BOOTPATH
2082 CONFIG_BOOTP_BOOTFILESIZE
2085 CONFIG_BOOTP_SEND_HOSTNAME
2086 CONFIG_BOOTP_NTPSERVER
2087 CONFIG_BOOTP_TIMEOFFSET
2088 CONFIG_BOOTP_VENDOREX
2089 CONFIG_BOOTP_MAY_FAIL
2091 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
2092 environment variable, not the BOOTP server.
2094 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
2095 after the configured retry count, the call will fail
2096 instead of starting over. This can be used to fail over
2097 to Link-local IP address configuration if the DHCP server
2100 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
2101 serverip from a DHCP server, it is possible that more
2102 than one DNS serverip is offered to the client.
2103 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
2104 serverip will be stored in the additional environment
2105 variable "dnsip2". The first DNS serverip is always
2106 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
2109 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2110 to do a dynamic update of a DNS server. To do this, they
2111 need the hostname of the DHCP requester.
2112 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2113 of the "hostname" environment variable is passed as
2114 option 12 to the DHCP server.
2116 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2118 A 32bit value in microseconds for a delay between
2119 receiving a "DHCP Offer" and sending the "DHCP Request".
2120 This fixes a problem with certain DHCP servers that don't
2121 respond 100% of the time to a "DHCP request". E.g. On an
2122 AT91RM9200 processor running at 180MHz, this delay needed
2123 to be *at least* 15,000 usec before a Windows Server 2003
2124 DHCP server would reply 100% of the time. I recommend at
2125 least 50,000 usec to be safe. The alternative is to hope
2126 that one of the retries will be successful but note that
2127 the DHCP timeout and retry process takes a longer than
2130 - Link-local IP address negotiation:
2131 Negotiate with other link-local clients on the local network
2132 for an address that doesn't require explicit configuration.
2133 This is especially useful if a DHCP server cannot be guaranteed
2134 to exist in all environments that the device must operate.
2136 See doc/README.link-local for more information.
2139 CONFIG_CDP_DEVICE_ID
2141 The device id used in CDP trigger frames.
2143 CONFIG_CDP_DEVICE_ID_PREFIX
2145 A two character string which is prefixed to the MAC address
2150 A printf format string which contains the ascii name of
2151 the port. Normally is set to "eth%d" which sets
2152 eth0 for the first Ethernet, eth1 for the second etc.
2154 CONFIG_CDP_CAPABILITIES
2156 A 32bit integer which indicates the device capabilities;
2157 0x00000010 for a normal host which does not forwards.
2161 An ascii string containing the version of the software.
2165 An ascii string containing the name of the platform.
2169 A 32bit integer sent on the trigger.
2171 CONFIG_CDP_POWER_CONSUMPTION
2173 A 16bit integer containing the power consumption of the
2174 device in .1 of milliwatts.
2176 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2178 A byte containing the id of the VLAN.
2180 - Status LED: CONFIG_STATUS_LED
2182 Several configurations allow to display the current
2183 status using a LED. For instance, the LED will blink
2184 fast while running U-Boot code, stop blinking as
2185 soon as a reply to a BOOTP request was received, and
2186 start blinking slow once the Linux kernel is running
2187 (supported by a status LED driver in the Linux
2188 kernel). Defining CONFIG_STATUS_LED enables this
2194 The status LED can be connected to a GPIO pin.
2195 In such cases, the gpio_led driver can be used as a
2196 status LED backend implementation. Define CONFIG_GPIO_LED
2197 to include the gpio_led driver in the U-Boot binary.
2199 CONFIG_GPIO_LED_INVERTED_TABLE
2200 Some GPIO connected LEDs may have inverted polarity in which
2201 case the GPIO high value corresponds to LED off state and
2202 GPIO low value corresponds to LED on state.
2203 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2204 with a list of GPIO LEDs that have inverted polarity.
2206 - CAN Support: CONFIG_CAN_DRIVER
2208 Defining CONFIG_CAN_DRIVER enables CAN driver support
2209 on those systems that support this (optional)
2210 feature, like the TQM8xxL modules.
2212 - I2C Support: CONFIG_SYS_I2C
2214 This enable the NEW i2c subsystem, and will allow you to use
2215 i2c commands at the u-boot command line (as long as you set
2216 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2217 based realtime clock chips or other i2c devices. See
2218 common/cmd_i2c.c for a description of the command line
2221 ported i2c driver to the new framework:
2222 - drivers/i2c/soft_i2c.c:
2223 - activate first bus with CONFIG_SYS_I2C_SOFT define
2224 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2225 for defining speed and slave address
2226 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2227 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2228 for defining speed and slave address
2229 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2230 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2231 for defining speed and slave address
2232 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2233 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2234 for defining speed and slave address
2236 - drivers/i2c/fsl_i2c.c:
2237 - activate i2c driver with CONFIG_SYS_I2C_FSL
2238 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2239 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2240 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2242 - If your board supports a second fsl i2c bus, define
2243 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2244 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2245 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2248 - drivers/i2c/tegra_i2c.c:
2249 - activate this driver with CONFIG_SYS_I2C_TEGRA
2250 - This driver adds 4 i2c buses with a fix speed from
2251 100000 and the slave addr 0!
2253 - drivers/i2c/ppc4xx_i2c.c
2254 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2255 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2256 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2258 - drivers/i2c/i2c_mxc.c
2259 - activate this driver with CONFIG_SYS_I2C_MXC
2260 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2261 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2262 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2263 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2264 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2265 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2266 If thoses defines are not set, default value is 100000
2267 for speed, and 0 for slave.
2269 - drivers/i2c/rcar_i2c.c:
2270 - activate this driver with CONFIG_SYS_I2C_RCAR
2271 - This driver adds 4 i2c buses
2273 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2274 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2275 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2276 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2277 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2278 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2279 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2280 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2281 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2283 - drivers/i2c/sh_i2c.c:
2284 - activate this driver with CONFIG_SYS_I2C_SH
2285 - This driver adds from 2 to 5 i2c buses
2287 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2288 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2289 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2290 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2291 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2292 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2293 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2294 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2295 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2296 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2297 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2298 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2299 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
2301 - drivers/i2c/omap24xx_i2c.c
2302 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2303 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2304 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2305 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2306 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2307 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2308 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2309 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2310 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2311 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2312 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2314 - drivers/i2c/zynq_i2c.c
2315 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2316 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2317 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2319 - drivers/i2c/s3c24x0_i2c.c:
2320 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2321 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2322 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2323 with a fix speed from 100000 and the slave addr 0!
2325 - drivers/i2c/ihs_i2c.c
2326 - activate this driver with CONFIG_SYS_I2C_IHS
2327 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
2328 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
2329 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
2330 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
2331 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
2332 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
2333 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
2334 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
2335 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
2336 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
2337 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
2338 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
2342 CONFIG_SYS_NUM_I2C_BUSES
2343 Hold the number of i2c busses you want to use. If you
2344 don't use/have i2c muxes on your i2c bus, this
2345 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2348 CONFIG_SYS_I2C_DIRECT_BUS
2349 define this, if you don't use i2c muxes on your hardware.
2350 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2353 CONFIG_SYS_I2C_MAX_HOPS
2354 define how many muxes are maximal consecutively connected
2355 on one i2c bus. If you not use i2c muxes, omit this
2358 CONFIG_SYS_I2C_BUSES
2359 hold a list of busses you want to use, only used if
2360 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2361 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2362 CONFIG_SYS_NUM_I2C_BUSES = 9:
2364 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2365 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2366 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2367 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2368 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2369 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2370 {1, {I2C_NULL_HOP}}, \
2371 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2372 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2376 bus 0 on adapter 0 without a mux
2377 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2378 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2379 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2380 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2381 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2382 bus 6 on adapter 1 without a mux
2383 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2384 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2386 If you do not have i2c muxes on your board, omit this define.
2388 - Legacy I2C Support: CONFIG_HARD_I2C
2390 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2391 provides the following compelling advantages:
2393 - more than one i2c adapter is usable
2394 - approved multibus support
2395 - better i2c mux support
2397 ** Please consider updating your I2C driver now. **
2399 These enable legacy I2C serial bus commands. Defining
2400 CONFIG_HARD_I2C will include the appropriate I2C driver
2401 for the selected CPU.
2403 This will allow you to use i2c commands at the u-boot
2404 command line (as long as you set CONFIG_CMD_I2C in
2405 CONFIG_COMMANDS) and communicate with i2c based realtime
2406 clock chips. See common/cmd_i2c.c for a description of the
2407 command line interface.
2409 CONFIG_HARD_I2C selects a hardware I2C controller.
2411 There are several other quantities that must also be
2412 defined when you define CONFIG_HARD_I2C.
2414 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2415 to be the frequency (in Hz) at which you wish your i2c bus
2416 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2417 the CPU's i2c node address).
2419 Now, the u-boot i2c code for the mpc8xx
2420 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2421 and so its address should therefore be cleared to 0 (See,
2422 eg, MPC823e User's Manual p.16-473). So, set
2423 CONFIG_SYS_I2C_SLAVE to 0.
2425 CONFIG_SYS_I2C_INIT_MPC5XXX
2427 When a board is reset during an i2c bus transfer
2428 chips might think that the current transfer is still
2429 in progress. Reset the slave devices by sending start
2430 commands until the slave device responds.
2432 That's all that's required for CONFIG_HARD_I2C.
2434 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2435 then the following macros need to be defined (examples are
2436 from include/configs/lwmon.h):
2440 (Optional). Any commands necessary to enable the I2C
2441 controller or configure ports.
2443 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2447 (Only for MPC8260 CPU). The I/O port to use (the code
2448 assumes both bits are on the same port). Valid values
2449 are 0..3 for ports A..D.
2453 The code necessary to make the I2C data line active
2454 (driven). If the data line is open collector, this
2457 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2461 The code necessary to make the I2C data line tri-stated
2462 (inactive). If the data line is open collector, this
2465 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2469 Code that returns true if the I2C data line is high,
2472 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2476 If <bit> is true, sets the I2C data line high. If it
2477 is false, it clears it (low).
2479 eg: #define I2C_SDA(bit) \
2480 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2481 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2485 If <bit> is true, sets the I2C clock line high. If it
2486 is false, it clears it (low).
2488 eg: #define I2C_SCL(bit) \
2489 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2490 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2494 This delay is invoked four times per clock cycle so this
2495 controls the rate of data transfer. The data rate thus
2496 is 1 / (I2C_DELAY * 4). Often defined to be something
2499 #define I2C_DELAY udelay(2)
2501 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2503 If your arch supports the generic GPIO framework (asm/gpio.h),
2504 then you may alternatively define the two GPIOs that are to be
2505 used as SCL / SDA. Any of the previous I2C_xxx macros will
2506 have GPIO-based defaults assigned to them as appropriate.
2508 You should define these to the GPIO value as given directly to
2509 the generic GPIO functions.
2511 CONFIG_SYS_I2C_INIT_BOARD
2513 When a board is reset during an i2c bus transfer
2514 chips might think that the current transfer is still
2515 in progress. On some boards it is possible to access
2516 the i2c SCLK line directly, either by using the
2517 processor pin as a GPIO or by having a second pin
2518 connected to the bus. If this option is defined a
2519 custom i2c_init_board() routine in boards/xxx/board.c
2520 is run early in the boot sequence.
2522 CONFIG_SYS_I2C_BOARD_LATE_INIT
2524 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2525 defined a custom i2c_board_late_init() routine in
2526 boards/xxx/board.c is run AFTER the operations in i2c_init()
2527 is completed. This callpoint can be used to unreset i2c bus
2528 using CPU i2c controller register accesses for CPUs whose i2c
2529 controller provide such a method. It is called at the end of
2530 i2c_init() to allow i2c_init operations to setup the i2c bus
2531 controller on the CPU (e.g. setting bus speed & slave address).
2533 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2535 This option enables configuration of bi_iic_fast[] flags
2536 in u-boot bd_info structure based on u-boot environment
2537 variable "i2cfast". (see also i2cfast)
2539 CONFIG_I2C_MULTI_BUS
2541 This option allows the use of multiple I2C buses, each of which
2542 must have a controller. At any point in time, only one bus is
2543 active. To switch to a different bus, use the 'i2c dev' command.
2544 Note that bus numbering is zero-based.
2546 CONFIG_SYS_I2C_NOPROBES
2548 This option specifies a list of I2C devices that will be skipped
2549 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2550 is set, specify a list of bus-device pairs. Otherwise, specify
2551 a 1D array of device addresses
2554 #undef CONFIG_I2C_MULTI_BUS
2555 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2557 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2559 #define CONFIG_I2C_MULTI_BUS
2560 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2562 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2564 CONFIG_SYS_SPD_BUS_NUM
2566 If defined, then this indicates the I2C bus number for DDR SPD.
2567 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2569 CONFIG_SYS_RTC_BUS_NUM
2571 If defined, then this indicates the I2C bus number for the RTC.
2572 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2574 CONFIG_SYS_DTT_BUS_NUM
2576 If defined, then this indicates the I2C bus number for the DTT.
2577 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2579 CONFIG_SYS_I2C_DTT_ADDR:
2581 If defined, specifies the I2C address of the DTT device.
2582 If not defined, then U-Boot uses predefined value for
2583 specified DTT device.
2585 CONFIG_SOFT_I2C_READ_REPEATED_START
2587 defining this will force the i2c_read() function in
2588 the soft_i2c driver to perform an I2C repeated start
2589 between writing the address pointer and reading the
2590 data. If this define is omitted the default behaviour
2591 of doing a stop-start sequence will be used. Most I2C
2592 devices can use either method, but some require one or
2595 - SPI Support: CONFIG_SPI
2597 Enables SPI driver (so far only tested with
2598 SPI EEPROM, also an instance works with Crystal A/D and
2599 D/As on the SACSng board)
2603 Enables the driver for SPI controller on SuperH. Currently
2604 only SH7757 is supported.
2608 Enables extended (16-bit) SPI EEPROM addressing.
2609 (symmetrical to CONFIG_I2C_X)
2613 Enables a software (bit-bang) SPI driver rather than
2614 using hardware support. This is a general purpose
2615 driver that only requires three general I/O port pins
2616 (two outputs, one input) to function. If this is
2617 defined, the board configuration must define several
2618 SPI configuration items (port pins to use, etc). For
2619 an example, see include/configs/sacsng.h.
2623 Enables a hardware SPI driver for general-purpose reads
2624 and writes. As with CONFIG_SOFT_SPI, the board configuration
2625 must define a list of chip-select function pointers.
2626 Currently supported on some MPC8xxx processors. For an
2627 example, see include/configs/mpc8349emds.h.
2631 Enables the driver for the SPI controllers on i.MX and MXC
2632 SoCs. Currently i.MX31/35/51 are supported.
2634 CONFIG_SYS_SPI_MXC_WAIT
2635 Timeout for waiting until spi transfer completed.
2636 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2638 - FPGA Support: CONFIG_FPGA
2640 Enables FPGA subsystem.
2642 CONFIG_FPGA_<vendor>
2644 Enables support for specific chip vendors.
2647 CONFIG_FPGA_<family>
2649 Enables support for FPGA family.
2650 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2654 Specify the number of FPGA devices to support.
2656 CONFIG_CMD_FPGA_LOADMK
2658 Enable support for fpga loadmk command
2660 CONFIG_CMD_FPGA_LOADP
2662 Enable support for fpga loadp command - load partial bitstream
2664 CONFIG_CMD_FPGA_LOADBP
2666 Enable support for fpga loadbp command - load partial bitstream
2669 CONFIG_SYS_FPGA_PROG_FEEDBACK
2671 Enable printing of hash marks during FPGA configuration.
2673 CONFIG_SYS_FPGA_CHECK_BUSY
2675 Enable checks on FPGA configuration interface busy
2676 status by the configuration function. This option
2677 will require a board or device specific function to
2682 If defined, a function that provides delays in the FPGA
2683 configuration driver.
2685 CONFIG_SYS_FPGA_CHECK_CTRLC
2686 Allow Control-C to interrupt FPGA configuration
2688 CONFIG_SYS_FPGA_CHECK_ERROR
2690 Check for configuration errors during FPGA bitfile
2691 loading. For example, abort during Virtex II
2692 configuration if the INIT_B line goes low (which
2693 indicated a CRC error).
2695 CONFIG_SYS_FPGA_WAIT_INIT
2697 Maximum time to wait for the INIT_B line to deassert
2698 after PROB_B has been deasserted during a Virtex II
2699 FPGA configuration sequence. The default time is 500
2702 CONFIG_SYS_FPGA_WAIT_BUSY
2704 Maximum time to wait for BUSY to deassert during
2705 Virtex II FPGA configuration. The default is 5 ms.
2707 CONFIG_SYS_FPGA_WAIT_CONFIG
2709 Time to wait after FPGA configuration. The default is
2712 - Configuration Management:
2715 If defined, this string will be added to the U-Boot
2716 version information (U_BOOT_VERSION)
2718 - Vendor Parameter Protection:
2720 U-Boot considers the values of the environment
2721 variables "serial#" (Board Serial Number) and
2722 "ethaddr" (Ethernet Address) to be parameters that
2723 are set once by the board vendor / manufacturer, and
2724 protects these variables from casual modification by
2725 the user. Once set, these variables are read-only,
2726 and write or delete attempts are rejected. You can
2727 change this behaviour:
2729 If CONFIG_ENV_OVERWRITE is #defined in your config
2730 file, the write protection for vendor parameters is
2731 completely disabled. Anybody can change or delete
2734 Alternatively, if you #define _both_ CONFIG_ETHADDR
2735 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2736 Ethernet address is installed in the environment,
2737 which can be changed exactly ONCE by the user. [The
2738 serial# is unaffected by this, i. e. it remains
2741 The same can be accomplished in a more flexible way
2742 for any variable by configuring the type of access
2743 to allow for those variables in the ".flags" variable
2744 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2749 Define this variable to enable the reservation of
2750 "protected RAM", i. e. RAM which is not overwritten
2751 by U-Boot. Define CONFIG_PRAM to hold the number of
2752 kB you want to reserve for pRAM. You can overwrite
2753 this default value by defining an environment
2754 variable "pram" to the number of kB you want to
2755 reserve. Note that the board info structure will
2756 still show the full amount of RAM. If pRAM is
2757 reserved, a new environment variable "mem" will
2758 automatically be defined to hold the amount of
2759 remaining RAM in a form that can be passed as boot
2760 argument to Linux, for instance like that:
2762 setenv bootargs ... mem=\${mem}
2765 This way you can tell Linux not to use this memory,
2766 either, which results in a memory region that will
2767 not be affected by reboots.
2769 *WARNING* If your board configuration uses automatic
2770 detection of the RAM size, you must make sure that
2771 this memory test is non-destructive. So far, the
2772 following board configurations are known to be
2775 IVMS8, IVML24, SPD8xx, TQM8xxL,
2776 HERMES, IP860, RPXlite, LWMON,
2779 - Access to physical memory region (> 4GB)
2780 Some basic support is provided for operations on memory not
2781 normally accessible to U-Boot - e.g. some architectures
2782 support access to more than 4GB of memory on 32-bit
2783 machines using physical address extension or similar.
2784 Define CONFIG_PHYSMEM to access this basic support, which
2785 currently only supports clearing the memory.
2790 Define this variable to stop the system in case of a
2791 fatal error, so that you have to reset it manually.
2792 This is probably NOT a good idea for an embedded
2793 system where you want the system to reboot
2794 automatically as fast as possible, but it may be
2795 useful during development since you can try to debug
2796 the conditions that lead to the situation.
2798 CONFIG_NET_RETRY_COUNT
2800 This variable defines the number of retries for
2801 network operations like ARP, RARP, TFTP, or BOOTP
2802 before giving up the operation. If not defined, a
2803 default value of 5 is used.
2807 Timeout waiting for an ARP reply in milliseconds.
2811 Timeout in milliseconds used in NFS protocol.
2812 If you encounter "ERROR: Cannot umount" in nfs command,
2813 try longer timeout such as
2814 #define CONFIG_NFS_TIMEOUT 10000UL
2816 - Command Interpreter:
2817 CONFIG_AUTO_COMPLETE
2819 Enable auto completion of commands using TAB.
2821 Note that this feature has NOT been implemented yet
2822 for the "hush" shell.
2825 CONFIG_SYS_HUSH_PARSER
2827 Define this variable to enable the "hush" shell (from
2828 Busybox) as command line interpreter, thus enabling
2829 powerful command line syntax like
2830 if...then...else...fi conditionals or `&&' and '||'
2831 constructs ("shell scripts").
2833 If undefined, you get the old, much simpler behaviour
2834 with a somewhat smaller memory footprint.
2837 CONFIG_SYS_PROMPT_HUSH_PS2
2839 This defines the secondary prompt string, which is
2840 printed when the command interpreter needs more input
2841 to complete a command. Usually "> ".
2845 In the current implementation, the local variables
2846 space and global environment variables space are
2847 separated. Local variables are those you define by
2848 simply typing `name=value'. To access a local
2849 variable later on, you have write `$name' or
2850 `${name}'; to execute the contents of a variable
2851 directly type `$name' at the command prompt.
2853 Global environment variables are those you use
2854 setenv/printenv to work with. To run a command stored
2855 in such a variable, you need to use the run command,
2856 and you must not use the '$' sign to access them.
2858 To store commands and special characters in a
2859 variable, please use double quotation marks
2860 surrounding the whole text of the variable, instead
2861 of the backslashes before semicolons and special
2864 - Commandline Editing and History:
2865 CONFIG_CMDLINE_EDITING
2867 Enable editing and History functions for interactive
2868 commandline input operations
2870 - Default Environment:
2871 CONFIG_EXTRA_ENV_SETTINGS
2873 Define this to contain any number of null terminated
2874 strings (variable = value pairs) that will be part of
2875 the default environment compiled into the boot image.
2877 For example, place something like this in your
2878 board's config file:
2880 #define CONFIG_EXTRA_ENV_SETTINGS \
2884 Warning: This method is based on knowledge about the
2885 internal format how the environment is stored by the
2886 U-Boot code. This is NOT an official, exported
2887 interface! Although it is unlikely that this format
2888 will change soon, there is no guarantee either.
2889 You better know what you are doing here.
2891 Note: overly (ab)use of the default environment is
2892 discouraged. Make sure to check other ways to preset
2893 the environment like the "source" command or the
2896 CONFIG_ENV_VARS_UBOOT_CONFIG
2898 Define this in order to add variables describing the
2899 U-Boot build configuration to the default environment.
2900 These will be named arch, cpu, board, vendor, and soc.
2902 Enabling this option will cause the following to be defined:
2910 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2912 Define this in order to add variables describing certain
2913 run-time determined information about the hardware to the
2914 environment. These will be named board_name, board_rev.
2916 CONFIG_DELAY_ENVIRONMENT
2918 Normally the environment is loaded when the board is
2919 intialised so that it is available to U-Boot. This inhibits
2920 that so that the environment is not available until
2921 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2922 this is instead controlled by the value of
2923 /config/load-environment.
2925 - DataFlash Support:
2926 CONFIG_HAS_DATAFLASH
2928 Defining this option enables DataFlash features and
2929 allows to read/write in Dataflash via the standard
2932 - Serial Flash support
2935 Defining this option enables SPI flash commands
2936 'sf probe/read/write/erase/update'.
2938 Usage requires an initial 'probe' to define the serial
2939 flash parameters, followed by read/write/erase/update
2942 The following defaults may be provided by the platform
2943 to handle the common case when only a single serial
2944 flash is present on the system.
2946 CONFIG_SF_DEFAULT_BUS Bus identifier
2947 CONFIG_SF_DEFAULT_CS Chip-select
2948 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2949 CONFIG_SF_DEFAULT_SPEED in Hz
2953 Define this option to include a destructive SPI flash
2956 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2958 Define this option to use the Bank addr/Extended addr
2959 support on SPI flashes which has size > 16Mbytes.
2961 CONFIG_SF_DUAL_FLASH Dual flash memories
2963 Define this option to use dual flash support where two flash
2964 memories can be connected with a given cs line.
2965 currently Xilinx Zynq qspi support these type of connections.
2967 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
2968 enable the W#/Vpp signal to disable writing to the status
2969 register on ST MICRON flashes like the N25Q128.
2970 The status register write enable/disable bit, combined with
2971 the W#/VPP signal provides hardware data protection for the
2972 device as follows: When the enable/disable bit is set to 1,
2973 and the W#/VPP signal is driven LOW, the status register
2974 nonvolatile bits become read-only and the WRITE STATUS REGISTER
2975 operation will not execute. The only way to exit this
2976 hardware-protected mode is to drive W#/VPP HIGH.
2978 - SystemACE Support:
2981 Adding this option adds support for Xilinx SystemACE
2982 chips attached via some sort of local bus. The address
2983 of the chip must also be defined in the
2984 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2986 #define CONFIG_SYSTEMACE
2987 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2989 When SystemACE support is added, the "ace" device type
2990 becomes available to the fat commands, i.e. fatls.
2992 - TFTP Fixed UDP Port:
2995 If this is defined, the environment variable tftpsrcp
2996 is used to supply the TFTP UDP source port value.
2997 If tftpsrcp isn't defined, the normal pseudo-random port
2998 number generator is used.
3000 Also, the environment variable tftpdstp is used to supply
3001 the TFTP UDP destination port value. If tftpdstp isn't
3002 defined, the normal port 69 is used.
3004 The purpose for tftpsrcp is to allow a TFTP server to
3005 blindly start the TFTP transfer using the pre-configured
3006 target IP address and UDP port. This has the effect of
3007 "punching through" the (Windows XP) firewall, allowing
3008 the remainder of the TFTP transfer to proceed normally.
3009 A better solution is to properly configure the firewall,
3010 but sometimes that is not allowed.
3015 This enables a generic 'hash' command which can produce
3016 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
3020 Enable the hash verify command (hash -v). This adds to code
3023 CONFIG_SHA1 - support SHA1 hashing
3024 CONFIG_SHA256 - support SHA256 hashing
3026 Note: There is also a sha1sum command, which should perhaps
3027 be deprecated in favour of 'hash sha1'.
3029 - Freescale i.MX specific commands:
3030 CONFIG_CMD_HDMIDETECT
3031 This enables 'hdmidet' command which returns true if an
3032 HDMI monitor is detected. This command is i.MX 6 specific.
3035 This enables the 'bmode' (bootmode) command for forcing
3036 a boot from specific media.
3038 This is useful for forcing the ROM's usb downloader to
3039 activate upon a watchdog reset which is nice when iterating
3040 on U-Boot. Using the reset button or running bmode normal
3041 will set it back to normal. This command currently
3042 supports i.MX53 and i.MX6.
3047 This enables the RSA algorithm used for FIT image verification
3048 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
3050 The signing part is build into mkimage regardless of this
3053 - bootcount support:
3054 CONFIG_BOOTCOUNT_LIMIT
3056 This enables the bootcounter support, see:
3057 http://www.denx.de/wiki/DULG/UBootBootCountLimit
3060 enable special bootcounter support on at91sam9xe based boards.
3062 enable special bootcounter support on blackfin based boards.
3064 enable special bootcounter support on da850 based boards.
3065 CONFIG_BOOTCOUNT_RAM
3066 enable support for the bootcounter in RAM
3067 CONFIG_BOOTCOUNT_I2C
3068 enable support for the bootcounter on an i2c (like RTC) device.
3069 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
3070 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
3072 CONFIG_BOOTCOUNT_ALEN = address len
3074 - Show boot progress:
3075 CONFIG_SHOW_BOOT_PROGRESS
3077 Defining this option allows to add some board-
3078 specific code (calling a user-provided function
3079 "show_boot_progress(int)") that enables you to show
3080 the system's boot progress on some display (for
3081 example, some LED's) on your board. At the moment,
3082 the following checkpoints are implemented:
3084 - Detailed boot stage timing
3086 Define this option to get detailed timing of each stage
3087 of the boot process.
3089 CONFIG_BOOTSTAGE_USER_COUNT
3090 This is the number of available user bootstage records.
3091 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
3092 a new ID will be allocated from this stash. If you exceed
3093 the limit, recording will stop.
3095 CONFIG_BOOTSTAGE_REPORT
3096 Define this to print a report before boot, similar to this:
3098 Timer summary in microseconds:
3101 3,575,678 3,575,678 board_init_f start
3102 3,575,695 17 arch_cpu_init A9
3103 3,575,777 82 arch_cpu_init done
3104 3,659,598 83,821 board_init_r start
3105 3,910,375 250,777 main_loop
3106 29,916,167 26,005,792 bootm_start
3107 30,361,327 445,160 start_kernel
3109 CONFIG_CMD_BOOTSTAGE
3110 Add a 'bootstage' command which supports printing a report
3111 and un/stashing of bootstage data.
3113 CONFIG_BOOTSTAGE_FDT
3114 Stash the bootstage information in the FDT. A root 'bootstage'
3115 node is created with each bootstage id as a child. Each child
3116 has a 'name' property and either 'mark' containing the
3117 mark time in microsecond, or 'accum' containing the
3118 accumulated time for that bootstage id in microseconds.
3123 name = "board_init_f";
3132 Code in the Linux kernel can find this in /proc/devicetree.
3134 Legacy uImage format:
3137 1 common/cmd_bootm.c before attempting to boot an image
3138 -1 common/cmd_bootm.c Image header has bad magic number
3139 2 common/cmd_bootm.c Image header has correct magic number
3140 -2 common/cmd_bootm.c Image header has bad checksum
3141 3 common/cmd_bootm.c Image header has correct checksum
3142 -3 common/cmd_bootm.c Image data has bad checksum
3143 4 common/cmd_bootm.c Image data has correct checksum
3144 -4 common/cmd_bootm.c Image is for unsupported architecture
3145 5 common/cmd_bootm.c Architecture check OK
3146 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
3147 6 common/cmd_bootm.c Image Type check OK
3148 -6 common/cmd_bootm.c gunzip uncompression error
3149 -7 common/cmd_bootm.c Unimplemented compression type
3150 7 common/cmd_bootm.c Uncompression OK
3151 8 common/cmd_bootm.c No uncompress/copy overwrite error
3152 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3154 9 common/image.c Start initial ramdisk verification
3155 -10 common/image.c Ramdisk header has bad magic number
3156 -11 common/image.c Ramdisk header has bad checksum
3157 10 common/image.c Ramdisk header is OK
3158 -12 common/image.c Ramdisk data has bad checksum
3159 11 common/image.c Ramdisk data has correct checksum
3160 12 common/image.c Ramdisk verification complete, start loading
3161 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3162 13 common/image.c Start multifile image verification
3163 14 common/image.c No initial ramdisk, no multifile, continue.
3165 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3167 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3168 -31 post/post.c POST test failed, detected by post_output_backlog()
3169 -32 post/post.c POST test failed, detected by post_run_single()
3171 34 common/cmd_doc.c before loading a Image from a DOC device
3172 -35 common/cmd_doc.c Bad usage of "doc" command
3173 35 common/cmd_doc.c correct usage of "doc" command
3174 -36 common/cmd_doc.c No boot device
3175 36 common/cmd_doc.c correct boot device
3176 -37 common/cmd_doc.c Unknown Chip ID on boot device
3177 37 common/cmd_doc.c correct chip ID found, device available
3178 -38 common/cmd_doc.c Read Error on boot device
3179 38 common/cmd_doc.c reading Image header from DOC device OK
3180 -39 common/cmd_doc.c Image header has bad magic number
3181 39 common/cmd_doc.c Image header has correct magic number
3182 -40 common/cmd_doc.c Error reading Image from DOC device
3183 40 common/cmd_doc.c Image header has correct magic number
3184 41 common/cmd_ide.c before loading a Image from a IDE device
3185 -42 common/cmd_ide.c Bad usage of "ide" command
3186 42 common/cmd_ide.c correct usage of "ide" command
3187 -43 common/cmd_ide.c No boot device
3188 43 common/cmd_ide.c boot device found
3189 -44 common/cmd_ide.c Device not available
3190 44 common/cmd_ide.c Device available
3191 -45 common/cmd_ide.c wrong partition selected
3192 45 common/cmd_ide.c partition selected
3193 -46 common/cmd_ide.c Unknown partition table
3194 46 common/cmd_ide.c valid partition table found
3195 -47 common/cmd_ide.c Invalid partition type
3196 47 common/cmd_ide.c correct partition type
3197 -48 common/cmd_ide.c Error reading Image Header on boot device
3198 48 common/cmd_ide.c reading Image Header from IDE device OK
3199 -49 common/cmd_ide.c Image header has bad magic number
3200 49 common/cmd_ide.c Image header has correct magic number
3201 -50 common/cmd_ide.c Image header has bad checksum
3202 50 common/cmd_ide.c Image header has correct checksum
3203 -51 common/cmd_ide.c Error reading Image from IDE device
3204 51 common/cmd_ide.c reading Image from IDE device OK
3205 52 common/cmd_nand.c before loading a Image from a NAND device
3206 -53 common/cmd_nand.c Bad usage of "nand" command
3207 53 common/cmd_nand.c correct usage of "nand" command
3208 -54 common/cmd_nand.c No boot device
3209 54 common/cmd_nand.c boot device found
3210 -55 common/cmd_nand.c Unknown Chip ID on boot device
3211 55 common/cmd_nand.c correct chip ID found, device available
3212 -56 common/cmd_nand.c Error reading Image Header on boot device
3213 56 common/cmd_nand.c reading Image Header from NAND device OK
3214 -57 common/cmd_nand.c Image header has bad magic number
3215 57 common/cmd_nand.c Image header has correct magic number
3216 -58 common/cmd_nand.c Error reading Image from NAND device
3217 58 common/cmd_nand.c reading Image from NAND device OK
3219 -60 common/env_common.c Environment has a bad CRC, using default
3221 64 net/eth.c starting with Ethernet configuration.
3222 -64 net/eth.c no Ethernet found.
3223 65 net/eth.c Ethernet found.
3225 -80 common/cmd_net.c usage wrong
3226 80 common/cmd_net.c before calling NetLoop()
3227 -81 common/cmd_net.c some error in NetLoop() occurred
3228 81 common/cmd_net.c NetLoop() back without error
3229 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3230 82 common/cmd_net.c trying automatic boot
3231 83 common/cmd_net.c running "source" command
3232 -83 common/cmd_net.c some error in automatic boot or "source" command
3233 84 common/cmd_net.c end without errors
3238 100 common/cmd_bootm.c Kernel FIT Image has correct format
3239 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3240 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3241 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3242 102 common/cmd_bootm.c Kernel unit name specified
3243 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3244 103 common/cmd_bootm.c Found configuration node
3245 104 common/cmd_bootm.c Got kernel subimage node offset
3246 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3247 105 common/cmd_bootm.c Kernel subimage hash verification OK
3248 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3249 106 common/cmd_bootm.c Architecture check OK
3250 -106 common/cmd_bootm.c Kernel subimage has wrong type
3251 107 common/cmd_bootm.c Kernel subimage type OK
3252 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3253 108 common/cmd_bootm.c Got kernel subimage data/size
3254 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3255 -109 common/cmd_bootm.c Can't get kernel subimage type
3256 -110 common/cmd_bootm.c Can't get kernel subimage comp
3257 -111 common/cmd_bootm.c Can't get kernel subimage os
3258 -112 common/cmd_bootm.c Can't get kernel subimage load address
3259 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3261 120 common/image.c Start initial ramdisk verification
3262 -120 common/image.c Ramdisk FIT image has incorrect format
3263 121 common/image.c Ramdisk FIT image has correct format
3264 122 common/image.c No ramdisk subimage unit name, using configuration
3265 -122 common/image.c Can't get configuration for ramdisk subimage
3266 123 common/image.c Ramdisk unit name specified
3267 -124 common/image.c Can't get ramdisk subimage node offset
3268 125 common/image.c Got ramdisk subimage node offset
3269 -125 common/image.c Ramdisk subimage hash verification failed
3270 126 common/image.c Ramdisk subimage hash verification OK
3271 -126 common/image.c Ramdisk subimage for unsupported architecture
3272 127 common/image.c Architecture check OK
3273 -127 common/image.c Can't get ramdisk subimage data/size
3274 128 common/image.c Got ramdisk subimage data/size
3275 129 common/image.c Can't get ramdisk load address
3276 -129 common/image.c Got ramdisk load address
3278 -130 common/cmd_doc.c Incorrect FIT image format
3279 131 common/cmd_doc.c FIT image format OK
3281 -140 common/cmd_ide.c Incorrect FIT image format
3282 141 common/cmd_ide.c FIT image format OK
3284 -150 common/cmd_nand.c Incorrect FIT image format
3285 151 common/cmd_nand.c FIT image format OK
3287 - legacy image format:
3288 CONFIG_IMAGE_FORMAT_LEGACY
3289 enables the legacy image format support in U-Boot.
3292 enabled if CONFIG_FIT_SIGNATURE is not defined.
3294 CONFIG_DISABLE_IMAGE_LEGACY
3295 disable the legacy image format
3297 This define is introduced, as the legacy image format is
3298 enabled per default for backward compatibility.
3300 - FIT image support:
3302 Enable support for the FIT uImage format.
3304 CONFIG_FIT_BEST_MATCH
3305 When no configuration is explicitly selected, default to the
3306 one whose fdt's compatibility field best matches that of
3307 U-Boot itself. A match is considered "best" if it matches the
3308 most specific compatibility entry of U-Boot's fdt's root node.
3309 The order of entries in the configuration's fdt is ignored.
3311 CONFIG_FIT_SIGNATURE
3312 This option enables signature verification of FIT uImages,
3313 using a hash signed and verified using RSA. See
3314 doc/uImage.FIT/signature.txt for more details.
3316 WARNING: When relying on signed FIT images with required
3317 signature check the legacy image format is default
3318 disabled. If a board need legacy image format support
3319 enable this through CONFIG_IMAGE_FORMAT_LEGACY
3321 CONFIG_FIT_DISABLE_SHA256
3322 Supporting SHA256 hashes has quite an impact on binary size.
3323 For constrained systems sha256 hash support can be disabled
3326 - Standalone program support:
3327 CONFIG_STANDALONE_LOAD_ADDR
3329 This option defines a board specific value for the
3330 address where standalone program gets loaded, thus
3331 overwriting the architecture dependent default
3334 - Frame Buffer Address:
3337 Define CONFIG_FB_ADDR if you want to use specific
3338 address for frame buffer. This is typically the case
3339 when using a graphics controller has separate video
3340 memory. U-Boot will then place the frame buffer at
3341 the given address instead of dynamically reserving it
3342 in system RAM by calling lcd_setmem(), which grabs
3343 the memory for the frame buffer depending on the
3344 configured panel size.
3346 Please see board_init_f function.
3348 - Automatic software updates via TFTP server
3350 CONFIG_UPDATE_TFTP_CNT_MAX
3351 CONFIG_UPDATE_TFTP_MSEC_MAX
3353 These options enable and control the auto-update feature;
3354 for a more detailed description refer to doc/README.update.
3356 - MTD Support (mtdparts command, UBI support)
3359 Adds the MTD device infrastructure from the Linux kernel.
3360 Needed for mtdparts command support.
3362 CONFIG_MTD_PARTITIONS
3364 Adds the MTD partitioning infrastructure from the Linux
3365 kernel. Needed for UBI support.
3367 CONFIG_MTD_NAND_VERIFY_WRITE
3368 verify if the written data is correct reread.
3373 Adds commands for interacting with MTD partitions formatted
3374 with the UBI flash translation layer
3376 Requires also defining CONFIG_RBTREE
3378 CONFIG_UBI_SILENCE_MSG
3380 Make the verbose messages from UBI stop printing. This leaves
3381 warnings and errors enabled.
3384 CONFIG_MTD_UBI_WL_THRESHOLD
3385 This parameter defines the maximum difference between the highest
3386 erase counter value and the lowest erase counter value of eraseblocks
3387 of UBI devices. When this threshold is exceeded, UBI starts performing
3388 wear leveling by means of moving data from eraseblock with low erase
3389 counter to eraseblocks with high erase counter.
3391 The default value should be OK for SLC NAND flashes, NOR flashes and
3392 other flashes which have eraseblock life-cycle 100000 or more.
3393 However, in case of MLC NAND flashes which typically have eraseblock
3394 life-cycle less than 10000, the threshold should be lessened (e.g.,
3395 to 128 or 256, although it does not have to be power of 2).
3399 CONFIG_MTD_UBI_BEB_LIMIT
3400 This option specifies the maximum bad physical eraseblocks UBI
3401 expects on the MTD device (per 1024 eraseblocks). If the
3402 underlying flash does not admit of bad eraseblocks (e.g. NOR
3403 flash), this value is ignored.
3405 NAND datasheets often specify the minimum and maximum NVM
3406 (Number of Valid Blocks) for the flashes' endurance lifetime.
3407 The maximum expected bad eraseblocks per 1024 eraseblocks
3408 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
3409 which gives 20 for most NANDs (MaxNVB is basically the total
3410 count of eraseblocks on the chip).
3412 To put it differently, if this value is 20, UBI will try to
3413 reserve about 1.9% of physical eraseblocks for bad blocks
3414 handling. And that will be 1.9% of eraseblocks on the entire
3415 NAND chip, not just the MTD partition UBI attaches. This means
3416 that if you have, say, a NAND flash chip admits maximum 40 bad
3417 eraseblocks, and it is split on two MTD partitions of the same
3418 size, UBI will reserve 40 eraseblocks when attaching a
3423 CONFIG_MTD_UBI_FASTMAP
3424 Fastmap is a mechanism which allows attaching an UBI device
3425 in nearly constant time. Instead of scanning the whole MTD device it
3426 only has to locate a checkpoint (called fastmap) on the device.
3427 The on-flash fastmap contains all information needed to attach
3428 the device. Using fastmap makes only sense on large devices where
3429 attaching by scanning takes long. UBI will not automatically install
3430 a fastmap on old images, but you can set the UBI parameter
3431 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
3432 that fastmap-enabled images are still usable with UBI implementations
3433 without fastmap support. On typical flash devices the whole fastmap
3434 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
3436 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
3437 Set this parameter to enable fastmap automatically on images
3444 Adds commands for interacting with UBI volumes formatted as
3445 UBIFS. UBIFS is read-only in u-boot.
3447 Requires UBI support as well as CONFIG_LZO
3449 CONFIG_UBIFS_SILENCE_MSG
3451 Make the verbose messages from UBIFS stop printing. This leaves
3452 warnings and errors enabled.
3456 Enable building of SPL globally.
3459 LDSCRIPT for linking the SPL binary.
3461 CONFIG_SPL_MAX_FOOTPRINT
3462 Maximum size in memory allocated to the SPL, BSS included.
3463 When defined, the linker checks that the actual memory
3464 used by SPL from _start to __bss_end does not exceed it.
3465 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3466 must not be both defined at the same time.
3469 Maximum size of the SPL image (text, data, rodata, and
3470 linker lists sections), BSS excluded.
3471 When defined, the linker checks that the actual size does
3474 CONFIG_SPL_TEXT_BASE
3475 TEXT_BASE for linking the SPL binary.
3477 CONFIG_SPL_RELOC_TEXT_BASE
3478 Address to relocate to. If unspecified, this is equal to
3479 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3481 CONFIG_SPL_BSS_START_ADDR
3482 Link address for the BSS within the SPL binary.
3484 CONFIG_SPL_BSS_MAX_SIZE
3485 Maximum size in memory allocated to the SPL BSS.
3486 When defined, the linker checks that the actual memory used
3487 by SPL from __bss_start to __bss_end does not exceed it.
3488 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3489 must not be both defined at the same time.
3492 Adress of the start of the stack SPL will use
3494 CONFIG_SPL_RELOC_STACK
3495 Adress of the start of the stack SPL will use after
3496 relocation. If unspecified, this is equal to
3499 CONFIG_SYS_SPL_MALLOC_START
3500 Starting address of the malloc pool used in SPL.
3502 CONFIG_SYS_SPL_MALLOC_SIZE
3503 The size of the malloc pool used in SPL.
3505 CONFIG_SPL_FRAMEWORK
3506 Enable the SPL framework under common/. This framework
3507 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3508 NAND loading of the Linux Kernel.
3511 Enable booting directly to an OS from SPL.
3512 See also: doc/README.falcon
3514 CONFIG_SPL_DISPLAY_PRINT
3515 For ARM, enable an optional function to print more information
3516 about the running system.
3518 CONFIG_SPL_INIT_MINIMAL
3519 Arch init code should be built for a very small image
3521 CONFIG_SPL_LIBCOMMON_SUPPORT
3522 Support for common/libcommon.o in SPL binary
3524 CONFIG_SPL_LIBDISK_SUPPORT
3525 Support for disk/libdisk.o in SPL binary
3527 CONFIG_SPL_I2C_SUPPORT
3528 Support for drivers/i2c/libi2c.o in SPL binary
3530 CONFIG_SPL_GPIO_SUPPORT
3531 Support for drivers/gpio/libgpio.o in SPL binary
3533 CONFIG_SPL_MMC_SUPPORT
3534 Support for drivers/mmc/libmmc.o in SPL binary
3536 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3537 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3538 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3539 Address, size and partition on the MMC to load U-Boot from
3540 when the MMC is being used in raw mode.
3542 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3543 Sector to load kernel uImage from when MMC is being
3544 used in raw mode (for Falcon mode)
3546 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3547 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3548 Sector and number of sectors to load kernel argument
3549 parameters from when MMC is being used in raw mode
3552 CONFIG_SPL_FAT_SUPPORT
3553 Support for fs/fat/libfat.o in SPL binary
3555 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3556 Filename to read to load U-Boot when reading from FAT
3558 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3559 Filename to read to load kernel uImage when reading
3560 from FAT (for Falcon mode)
3562 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3563 Filename to read to load kernel argument parameters
3564 when reading from FAT (for Falcon mode)
3566 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3567 Set this for NAND SPL on PPC mpc83xx targets, so that
3568 start.S waits for the rest of the SPL to load before
3569 continuing (the hardware starts execution after just
3570 loading the first page rather than the full 4K).
3572 CONFIG_SPL_SKIP_RELOCATE
3573 Avoid SPL relocation
3575 CONFIG_SPL_NAND_BASE
3576 Include nand_base.c in the SPL. Requires
3577 CONFIG_SPL_NAND_DRIVERS.
3579 CONFIG_SPL_NAND_DRIVERS
3580 SPL uses normal NAND drivers, not minimal drivers.
3583 Include standard software ECC in the SPL
3585 CONFIG_SPL_NAND_SIMPLE
3586 Support for NAND boot using simple NAND drivers that
3587 expose the cmd_ctrl() interface.
3589 CONFIG_SPL_MTD_SUPPORT
3590 Support for the MTD subsystem within SPL. Useful for
3591 environment on NAND support within SPL.
3593 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3594 Set for the SPL on PPC mpc8xxx targets, support for
3595 drivers/ddr/fsl/libddr.o in SPL binary.
3597 CONFIG_SPL_COMMON_INIT_DDR
3598 Set for common ddr init with serial presence detect in
3601 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3602 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3603 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3604 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3605 CONFIG_SYS_NAND_ECCBYTES
3606 Defines the size and behavior of the NAND that SPL uses
3609 CONFIG_SPL_NAND_BOOT
3610 Add support NAND boot
3612 CONFIG_SYS_NAND_U_BOOT_OFFS
3613 Location in NAND to read U-Boot from
3615 CONFIG_SYS_NAND_U_BOOT_DST
3616 Location in memory to load U-Boot to
3618 CONFIG_SYS_NAND_U_BOOT_SIZE
3619 Size of image to load
3621 CONFIG_SYS_NAND_U_BOOT_START
3622 Entry point in loaded image to jump to
3624 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3625 Define this if you need to first read the OOB and then the
3626 data. This is used for example on davinci plattforms.
3628 CONFIG_SPL_OMAP3_ID_NAND
3629 Support for an OMAP3-specific set of functions to return the
3630 ID and MFR of the first attached NAND chip, if present.
3632 CONFIG_SPL_SERIAL_SUPPORT
3633 Support for drivers/serial/libserial.o in SPL binary
3635 CONFIG_SPL_SPI_FLASH_SUPPORT
3636 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3638 CONFIG_SPL_SPI_SUPPORT
3639 Support for drivers/spi/libspi.o in SPL binary
3641 CONFIG_SPL_RAM_DEVICE
3642 Support for running image already present in ram, in SPL binary
3644 CONFIG_SPL_LIBGENERIC_SUPPORT
3645 Support for lib/libgeneric.o in SPL binary
3647 CONFIG_SPL_ENV_SUPPORT
3648 Support for the environment operating in SPL binary
3650 CONFIG_SPL_NET_SUPPORT
3651 Support for the net/libnet.o in SPL binary.
3652 It conflicts with SPL env from storage medium specified by
3653 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3656 Image offset to which the SPL should be padded before appending
3657 the SPL payload. By default, this is defined as
3658 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3659 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3660 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3663 Final target image containing SPL and payload. Some SPLs
3664 use an arch-specific makefile fragment instead, for
3665 example if more than one image needs to be produced.
3667 CONFIG_FIT_SPL_PRINT
3668 Printing information about a FIT image adds quite a bit of
3669 code to SPL. So this is normally disabled in SPL. Use this
3670 option to re-enable it. This will affect the output of the
3671 bootm command when booting a FIT image.
3675 Enable building of TPL globally.
3678 Image offset to which the TPL should be padded before appending
3679 the TPL payload. By default, this is defined as
3680 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3681 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3682 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3687 [so far only for SMDK2400 boards]
3689 - Modem support enable:
3690 CONFIG_MODEM_SUPPORT
3692 - RTS/CTS Flow control enable:
3695 - Modem debug support:
3696 CONFIG_MODEM_SUPPORT_DEBUG
3698 Enables debugging stuff (char screen[1024], dbg())
3699 for modem support. Useful only with BDI2000.
3701 - Interrupt support (PPC):
3703 There are common interrupt_init() and timer_interrupt()
3704 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3705 for CPU specific initialization. interrupt_init_cpu()
3706 should set decrementer_count to appropriate value. If
3707 CPU resets decrementer automatically after interrupt
3708 (ppc4xx) it should set decrementer_count to zero.
3709 timer_interrupt() calls timer_interrupt_cpu() for CPU
3710 specific handling. If board has watchdog / status_led
3711 / other_activity_monitor it works automatically from
3712 general timer_interrupt().
3716 In the target system modem support is enabled when a
3717 specific key (key combination) is pressed during
3718 power-on. Otherwise U-Boot will boot normally
3719 (autoboot). The key_pressed() function is called from
3720 board_init(). Currently key_pressed() is a dummy
3721 function, returning 1 and thus enabling modem
3724 If there are no modem init strings in the
3725 environment, U-Boot proceed to autoboot; the
3726 previous output (banner, info printfs) will be
3729 See also: doc/README.Modem
3731 Board initialization settings:
3732 ------------------------------
3734 During Initialization u-boot calls a number of board specific functions
3735 to allow the preparation of board specific prerequisites, e.g. pin setup
3736 before drivers are initialized. To enable these callbacks the
3737 following configuration macros have to be defined. Currently this is
3738 architecture specific, so please check arch/your_architecture/lib/board.c
3739 typically in board_init_f() and board_init_r().
3741 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3742 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3743 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3744 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3746 Configuration Settings:
3747 -----------------------
3749 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3750 Optionally it can be defined to support 64-bit memory commands.
3752 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3753 undefine this when you're short of memory.
3755 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3756 width of the commands listed in the 'help' command output.
3758 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3759 prompt for user input.
3761 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3763 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3765 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3767 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3768 the application (usually a Linux kernel) when it is
3771 - CONFIG_SYS_BAUDRATE_TABLE:
3772 List of legal baudrate settings for this board.
3774 - CONFIG_SYS_CONSOLE_INFO_QUIET
3775 Suppress display of console information at boot.
3777 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3778 If the board specific function
3779 extern int overwrite_console (void);
3780 returns 1, the stdin, stderr and stdout are switched to the
3781 serial port, else the settings in the environment are used.
3783 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3784 Enable the call to overwrite_console().
3786 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3787 Enable overwrite of previous console environment settings.
3789 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3790 Begin and End addresses of the area used by the
3793 - CONFIG_SYS_ALT_MEMTEST:
3794 Enable an alternate, more extensive memory test.
3796 - CONFIG_SYS_MEMTEST_SCRATCH:
3797 Scratch address used by the alternate memory test
3798 You only need to set this if address zero isn't writeable
3800 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3801 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3802 this specified memory area will get subtracted from the top
3803 (end) of RAM and won't get "touched" at all by U-Boot. By
3804 fixing up gd->ram_size the Linux kernel should gets passed
3805 the now "corrected" memory size and won't touch it either.
3806 This should work for arch/ppc and arch/powerpc. Only Linux
3807 board ports in arch/powerpc with bootwrapper support that
3808 recalculate the memory size from the SDRAM controller setup
3809 will have to get fixed in Linux additionally.
3811 This option can be used as a workaround for the 440EPx/GRx
3812 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3815 WARNING: Please make sure that this value is a multiple of
3816 the Linux page size (normally 4k). If this is not the case,
3817 then the end address of the Linux memory will be located at a
3818 non page size aligned address and this could cause major
3821 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3822 Enable temporary baudrate change while serial download
3824 - CONFIG_SYS_SDRAM_BASE:
3825 Physical start address of SDRAM. _Must_ be 0 here.
3827 - CONFIG_SYS_MBIO_BASE:
3828 Physical start address of Motherboard I/O (if using a
3831 - CONFIG_SYS_FLASH_BASE:
3832 Physical start address of Flash memory.
3834 - CONFIG_SYS_MONITOR_BASE:
3835 Physical start address of boot monitor code (set by
3836 make config files to be same as the text base address
3837 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3838 CONFIG_SYS_FLASH_BASE when booting from flash.
3840 - CONFIG_SYS_MONITOR_LEN:
3841 Size of memory reserved for monitor code, used to
3842 determine _at_compile_time_ (!) if the environment is
3843 embedded within the U-Boot image, or in a separate
3846 - CONFIG_SYS_MALLOC_LEN:
3847 Size of DRAM reserved for malloc() use.
3849 - CONFIG_SYS_MALLOC_F_LEN
3850 Size of the malloc() pool for use before relocation. If
3851 this is defined, then a very simple malloc() implementation
3852 will become available before relocation. The address is just
3853 below the global data, and the stack is moved down to make
3856 This feature allocates regions with increasing addresses
3857 within the region. calloc() is supported, but realloc()
3858 is not available. free() is supported but does nothing.
3859 The memory will be freed (or in fact just forgotton) when
3860 U-Boot relocates itself.
3862 Pre-relocation malloc() is only supported on ARM and sandbox
3863 at present but is fairly easy to enable for other archs.
3865 - CONFIG_SYS_BOOTM_LEN:
3866 Normally compressed uImages are limited to an
3867 uncompressed size of 8 MBytes. If this is not enough,
3868 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3869 to adjust this setting to your needs.
3871 - CONFIG_SYS_BOOTMAPSZ:
3872 Maximum size of memory mapped by the startup code of
3873 the Linux kernel; all data that must be processed by
3874 the Linux kernel (bd_info, boot arguments, FDT blob if
3875 used) must be put below this limit, unless "bootm_low"
3876 environment variable is defined and non-zero. In such case
3877 all data for the Linux kernel must be between "bootm_low"
3878 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3879 variable "bootm_mapsize" will override the value of
3880 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3881 then the value in "bootm_size" will be used instead.
3883 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3884 Enable initrd_high functionality. If defined then the
3885 initrd_high feature is enabled and the bootm ramdisk subcommand
3888 - CONFIG_SYS_BOOT_GET_CMDLINE:
3889 Enables allocating and saving kernel cmdline in space between
3890 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3892 - CONFIG_SYS_BOOT_GET_KBD:
3893 Enables allocating and saving a kernel copy of the bd_info in
3894 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3896 - CONFIG_SYS_MAX_FLASH_BANKS:
3897 Max number of Flash memory banks
3899 - CONFIG_SYS_MAX_FLASH_SECT:
3900 Max number of sectors on a Flash chip
3902 - CONFIG_SYS_FLASH_ERASE_TOUT:
3903 Timeout for Flash erase operations (in ms)
3905 - CONFIG_SYS_FLASH_WRITE_TOUT:
3906 Timeout for Flash write operations (in ms)
3908 - CONFIG_SYS_FLASH_LOCK_TOUT
3909 Timeout for Flash set sector lock bit operation (in ms)
3911 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3912 Timeout for Flash clear lock bits operation (in ms)
3914 - CONFIG_SYS_FLASH_PROTECTION
3915 If defined, hardware flash sectors protection is used
3916 instead of U-Boot software protection.
3918 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3920 Enable TFTP transfers directly to flash memory;
3921 without this option such a download has to be
3922 performed in two steps: (1) download to RAM, and (2)
3923 copy from RAM to flash.
3925 The two-step approach is usually more reliable, since
3926 you can check if the download worked before you erase
3927 the flash, but in some situations (when system RAM is
3928 too limited to allow for a temporary copy of the
3929 downloaded image) this option may be very useful.
3931 - CONFIG_SYS_FLASH_CFI:
3932 Define if the flash driver uses extra elements in the
3933 common flash structure for storing flash geometry.
3935 - CONFIG_FLASH_CFI_DRIVER
3936 This option also enables the building of the cfi_flash driver
3937 in the drivers directory
3939 - CONFIG_FLASH_CFI_MTD
3940 This option enables the building of the cfi_mtd driver
3941 in the drivers directory. The driver exports CFI flash
3944 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3945 Use buffered writes to flash.
3947 - CONFIG_FLASH_SPANSION_S29WS_N
3948 s29ws-n MirrorBit flash has non-standard addresses for buffered
3951 - CONFIG_SYS_FLASH_QUIET_TEST
3952 If this option is defined, the common CFI flash doesn't
3953 print it's warning upon not recognized FLASH banks. This
3954 is useful, if some of the configured banks are only
3955 optionally available.
3957 - CONFIG_FLASH_SHOW_PROGRESS
3958 If defined (must be an integer), print out countdown
3959 digits and dots. Recommended value: 45 (9..1) for 80
3960 column displays, 15 (3..1) for 40 column displays.
3962 - CONFIG_FLASH_VERIFY
3963 If defined, the content of the flash (destination) is compared
3964 against the source after the write operation. An error message
3965 will be printed when the contents are not identical.
3966 Please note that this option is useless in nearly all cases,
3967 since such flash programming errors usually are detected earlier
3968 while unprotecting/erasing/programming. Please only enable
3969 this option if you really know what you are doing.
3971 - CONFIG_SYS_RX_ETH_BUFFER:
3972 Defines the number of Ethernet receive buffers. On some
3973 Ethernet controllers it is recommended to set this value
3974 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3975 buffers can be full shortly after enabling the interface
3976 on high Ethernet traffic.
3977 Defaults to 4 if not defined.
3979 - CONFIG_ENV_MAX_ENTRIES
3981 Maximum number of entries in the hash table that is used
3982 internally to store the environment settings. The default
3983 setting is supposed to be generous and should work in most
3984 cases. This setting can be used to tune behaviour; see
3985 lib/hashtable.c for details.
3987 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3988 - CONFIG_ENV_FLAGS_LIST_STATIC
3989 Enable validation of the values given to environment variables when
3990 calling env set. Variables can be restricted to only decimal,
3991 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3992 the variables can also be restricted to IP address or MAC address.
3994 The format of the list is:
3995 type_attribute = [s|d|x|b|i|m]
3996 access_atribute = [a|r|o|c]
3997 attributes = type_attribute[access_atribute]
3998 entry = variable_name[:attributes]
4001 The type attributes are:
4002 s - String (default)
4005 b - Boolean ([1yYtT|0nNfF])
4009 The access attributes are:
4015 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4016 Define this to a list (string) to define the ".flags"
4017 envirnoment variable in the default or embedded environment.
4019 - CONFIG_ENV_FLAGS_LIST_STATIC
4020 Define this to a list (string) to define validation that
4021 should be done if an entry is not found in the ".flags"
4022 environment variable. To override a setting in the static
4023 list, simply add an entry for the same variable name to the
4026 - CONFIG_ENV_ACCESS_IGNORE_FORCE
4027 If defined, don't allow the -f switch to env set override variable
4030 - CONFIG_SYS_GENERIC_BOARD
4031 This selects the architecture-generic board system instead of the
4032 architecture-specific board files. It is intended to move boards
4033 to this new framework over time. Defining this will disable the
4034 arch/foo/lib/board.c file and use common/board_f.c and
4035 common/board_r.c instead. To use this option your architecture
4036 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
4037 its config.mk file). If you find problems enabling this option on
4038 your board please report the problem and send patches!
4040 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
4041 This is set by OMAP boards for the max time that reset should
4042 be asserted. See doc/README.omap-reset-time for details on how
4043 the value can be calulated on a given board.
4045 The following definitions that deal with the placement and management
4046 of environment data (variable area); in general, we support the
4047 following configurations:
4049 - CONFIG_BUILD_ENVCRC:
4051 Builds up envcrc with the target environment so that external utils
4052 may easily extract it and embed it in final U-Boot images.
4054 - CONFIG_ENV_IS_IN_FLASH:
4056 Define this if the environment is in flash memory.
4058 a) The environment occupies one whole flash sector, which is
4059 "embedded" in the text segment with the U-Boot code. This
4060 happens usually with "bottom boot sector" or "top boot
4061 sector" type flash chips, which have several smaller
4062 sectors at the start or the end. For instance, such a
4063 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
4064 such a case you would place the environment in one of the
4065 4 kB sectors - with U-Boot code before and after it. With
4066 "top boot sector" type flash chips, you would put the
4067 environment in one of the last sectors, leaving a gap
4068 between U-Boot and the environment.
4070 - CONFIG_ENV_OFFSET:
4072 Offset of environment data (variable area) to the
4073 beginning of flash memory; for instance, with bottom boot
4074 type flash chips the second sector can be used: the offset
4075 for this sector is given here.
4077 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
4081 This is just another way to specify the start address of
4082 the flash sector containing the environment (instead of
4085 - CONFIG_ENV_SECT_SIZE:
4087 Size of the sector containing the environment.
4090 b) Sometimes flash chips have few, equal sized, BIG sectors.
4091 In such a case you don't want to spend a whole sector for
4096 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
4097 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
4098 of this flash sector for the environment. This saves
4099 memory for the RAM copy of the environment.
4101 It may also save flash memory if you decide to use this
4102 when your environment is "embedded" within U-Boot code,
4103 since then the remainder of the flash sector could be used
4104 for U-Boot code. It should be pointed out that this is
4105 STRONGLY DISCOURAGED from a robustness point of view:
4106 updating the environment in flash makes it always
4107 necessary to erase the WHOLE sector. If something goes
4108 wrong before the contents has been restored from a copy in
4109 RAM, your target system will be dead.
4111 - CONFIG_ENV_ADDR_REDUND
4112 CONFIG_ENV_SIZE_REDUND
4114 These settings describe a second storage area used to hold
4115 a redundant copy of the environment data, so that there is
4116 a valid backup copy in case there is a power failure during
4117 a "saveenv" operation.
4119 BE CAREFUL! Any changes to the flash layout, and some changes to the
4120 source code will make it necessary to adapt <board>/u-boot.lds*
4124 - CONFIG_ENV_IS_IN_NVRAM:
4126 Define this if you have some non-volatile memory device
4127 (NVRAM, battery buffered SRAM) which you want to use for the
4133 These two #defines are used to determine the memory area you
4134 want to use for environment. It is assumed that this memory
4135 can just be read and written to, without any special
4138 BE CAREFUL! The first access to the environment happens quite early
4139 in U-Boot initalization (when we try to get the setting of for the
4140 console baudrate). You *MUST* have mapped your NVRAM area then, or
4143 Please note that even with NVRAM we still use a copy of the
4144 environment in RAM: we could work on NVRAM directly, but we want to
4145 keep settings there always unmodified except somebody uses "saveenv"
4146 to save the current settings.
4149 - CONFIG_ENV_IS_IN_EEPROM:
4151 Use this if you have an EEPROM or similar serial access
4152 device and a driver for it.
4154 - CONFIG_ENV_OFFSET:
4157 These two #defines specify the offset and size of the
4158 environment area within the total memory of your EEPROM.
4160 - CONFIG_SYS_I2C_EEPROM_ADDR:
4161 If defined, specified the chip address of the EEPROM device.
4162 The default address is zero.
4164 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
4165 If defined, the number of bits used to address bytes in a
4166 single page in the EEPROM device. A 64 byte page, for example
4167 would require six bits.
4169 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
4170 If defined, the number of milliseconds to delay between
4171 page writes. The default is zero milliseconds.
4173 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
4174 The length in bytes of the EEPROM memory array address. Note
4175 that this is NOT the chip address length!
4177 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
4178 EEPROM chips that implement "address overflow" are ones
4179 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
4180 address and the extra bits end up in the "chip address" bit
4181 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
4184 Note that we consider the length of the address field to
4185 still be one byte because the extra address bits are hidden
4186 in the chip address.
4188 - CONFIG_SYS_EEPROM_SIZE:
4189 The size in bytes of the EEPROM device.
4191 - CONFIG_ENV_EEPROM_IS_ON_I2C
4192 define this, if you have I2C and SPI activated, and your
4193 EEPROM, which holds the environment, is on the I2C bus.
4195 - CONFIG_I2C_ENV_EEPROM_BUS
4196 if you have an Environment on an EEPROM reached over
4197 I2C muxes, you can define here, how to reach this
4198 EEPROM. For example:
4200 #define CONFIG_I2C_ENV_EEPROM_BUS 1
4202 EEPROM which holds the environment, is reached over
4203 a pca9547 i2c mux with address 0x70, channel 3.
4205 - CONFIG_ENV_IS_IN_DATAFLASH:
4207 Define this if you have a DataFlash memory device which you
4208 want to use for the environment.
4210 - CONFIG_ENV_OFFSET:
4214 These three #defines specify the offset and size of the
4215 environment area within the total memory of your DataFlash placed
4216 at the specified address.
4218 - CONFIG_ENV_IS_IN_SPI_FLASH:
4220 Define this if you have a SPI Flash memory device which you
4221 want to use for the environment.
4223 - CONFIG_ENV_OFFSET:
4226 These two #defines specify the offset and size of the
4227 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
4228 aligned to an erase sector boundary.
4230 - CONFIG_ENV_SECT_SIZE:
4232 Define the SPI flash's sector size.
4234 - CONFIG_ENV_OFFSET_REDUND (optional):
4236 This setting describes a second storage area of CONFIG_ENV_SIZE
4237 size used to hold a redundant copy of the environment data, so
4238 that there is a valid backup copy in case there is a power failure
4239 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4240 aligned to an erase sector boundary.
4242 - CONFIG_ENV_SPI_BUS (optional):
4243 - CONFIG_ENV_SPI_CS (optional):
4245 Define the SPI bus and chip select. If not defined they will be 0.
4247 - CONFIG_ENV_SPI_MAX_HZ (optional):
4249 Define the SPI max work clock. If not defined then use 1MHz.
4251 - CONFIG_ENV_SPI_MODE (optional):
4253 Define the SPI work mode. If not defined then use SPI_MODE_3.
4255 - CONFIG_ENV_IS_IN_REMOTE:
4257 Define this if you have a remote memory space which you
4258 want to use for the local device's environment.
4263 These two #defines specify the address and size of the
4264 environment area within the remote memory space. The
4265 local device can get the environment from remote memory
4266 space by SRIO or PCIE links.
4268 BE CAREFUL! For some special cases, the local device can not use
4269 "saveenv" command. For example, the local device will get the
4270 environment stored in a remote NOR flash by SRIO or PCIE link,
4271 but it can not erase, write this NOR flash by SRIO or PCIE interface.
4273 - CONFIG_ENV_IS_IN_NAND:
4275 Define this if you have a NAND device which you want to use
4276 for the environment.
4278 - CONFIG_ENV_OFFSET:
4281 These two #defines specify the offset and size of the environment
4282 area within the first NAND device. CONFIG_ENV_OFFSET must be
4283 aligned to an erase block boundary.
4285 - CONFIG_ENV_OFFSET_REDUND (optional):
4287 This setting describes a second storage area of CONFIG_ENV_SIZE
4288 size used to hold a redundant copy of the environment data, so
4289 that there is a valid backup copy in case there is a power failure
4290 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4291 aligned to an erase block boundary.
4293 - CONFIG_ENV_RANGE (optional):
4295 Specifies the length of the region in which the environment
4296 can be written. This should be a multiple of the NAND device's
4297 block size. Specifying a range with more erase blocks than
4298 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
4299 the range to be avoided.
4301 - CONFIG_ENV_OFFSET_OOB (optional):
4303 Enables support for dynamically retrieving the offset of the
4304 environment from block zero's out-of-band data. The
4305 "nand env.oob" command can be used to record this offset.
4306 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4307 using CONFIG_ENV_OFFSET_OOB.
4309 - CONFIG_NAND_ENV_DST
4311 Defines address in RAM to which the nand_spl code should copy the
4312 environment. If redundant environment is used, it will be copied to
4313 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4315 - CONFIG_ENV_IS_IN_UBI:
4317 Define this if you have an UBI volume that you want to use for the
4318 environment. This has the benefit of wear-leveling the environment
4319 accesses, which is important on NAND.
4321 - CONFIG_ENV_UBI_PART:
4323 Define this to a string that is the mtd partition containing the UBI.
4325 - CONFIG_ENV_UBI_VOLUME:
4327 Define this to the name of the volume that you want to store the
4330 - CONFIG_ENV_UBI_VOLUME_REDUND:
4332 Define this to the name of another volume to store a second copy of
4333 the environment in. This will enable redundant environments in UBI.
4334 It is assumed that both volumes are in the same MTD partition.
4336 - CONFIG_UBI_SILENCE_MSG
4337 - CONFIG_UBIFS_SILENCE_MSG
4339 You will probably want to define these to avoid a really noisy system
4340 when storing the env in UBI.
4342 - CONFIG_ENV_IS_IN_FAT:
4343 Define this if you want to use the FAT file system for the environment.
4345 - FAT_ENV_INTERFACE:
4347 Define this to a string that is the name of the block device.
4349 - FAT_ENV_DEV_AND_PART:
4351 Define this to a string to specify the partition of the device. It can
4354 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
4355 - "D:P": device D partition P. Error occurs if device D has no
4358 - "D" or "D:": device D partition 1 if device D has partition
4359 table, or the whole device D if has no partition
4361 - "D:auto": first partition in device D with bootable flag set.
4362 If none, first valid paratition in device D. If no
4363 partition table then means device D.
4367 It's a string of the FAT file name. This file use to store the
4371 This should be defined. Otherwise it cannot save the envrionment file.
4373 - CONFIG_ENV_IS_IN_MMC:
4375 Define this if you have an MMC device which you want to use for the
4378 - CONFIG_SYS_MMC_ENV_DEV:
4380 Specifies which MMC device the environment is stored in.
4382 - CONFIG_SYS_MMC_ENV_PART (optional):
4384 Specifies which MMC partition the environment is stored in. If not
4385 set, defaults to partition 0, the user area. Common values might be
4386 1 (first MMC boot partition), 2 (second MMC boot partition).
4388 - CONFIG_ENV_OFFSET:
4391 These two #defines specify the offset and size of the environment
4392 area within the specified MMC device.
4394 If offset is positive (the usual case), it is treated as relative to
4395 the start of the MMC partition. If offset is negative, it is treated
4396 as relative to the end of the MMC partition. This can be useful if
4397 your board may be fitted with different MMC devices, which have
4398 different sizes for the MMC partitions, and you always want the
4399 environment placed at the very end of the partition, to leave the
4400 maximum possible space before it, to store other data.
4402 These two values are in units of bytes, but must be aligned to an
4403 MMC sector boundary.
4405 - CONFIG_ENV_OFFSET_REDUND (optional):
4407 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4408 hold a redundant copy of the environment data. This provides a
4409 valid backup copy in case the other copy is corrupted, e.g. due
4410 to a power failure during a "saveenv" operation.
4412 This value may also be positive or negative; this is handled in the
4413 same way as CONFIG_ENV_OFFSET.
4415 This value is also in units of bytes, but must also be aligned to
4416 an MMC sector boundary.
4418 - CONFIG_ENV_SIZE_REDUND (optional):
4420 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4421 set. If this value is set, it must be set to the same value as
4424 - CONFIG_SYS_SPI_INIT_OFFSET
4426 Defines offset to the initial SPI buffer area in DPRAM. The
4427 area is used at an early stage (ROM part) if the environment
4428 is configured to reside in the SPI EEPROM: We need a 520 byte
4429 scratch DPRAM area. It is used between the two initialization
4430 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4431 to be a good choice since it makes it far enough from the
4432 start of the data area as well as from the stack pointer.
4434 Please note that the environment is read-only until the monitor
4435 has been relocated to RAM and a RAM copy of the environment has been
4436 created; also, when using EEPROM you will have to use getenv_f()
4437 until then to read environment variables.
4439 The environment is protected by a CRC32 checksum. Before the monitor
4440 is relocated into RAM, as a result of a bad CRC you will be working
4441 with the compiled-in default environment - *silently*!!! [This is
4442 necessary, because the first environment variable we need is the
4443 "baudrate" setting for the console - if we have a bad CRC, we don't
4444 have any device yet where we could complain.]
4446 Note: once the monitor has been relocated, then it will complain if
4447 the default environment is used; a new CRC is computed as soon as you
4448 use the "saveenv" command to store a valid environment.
4450 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4451 Echo the inverted Ethernet link state to the fault LED.
4453 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4454 also needs to be defined.
4456 - CONFIG_SYS_FAULT_MII_ADDR:
4457 MII address of the PHY to check for the Ethernet link state.
4459 - CONFIG_NS16550_MIN_FUNCTIONS:
4460 Define this if you desire to only have use of the NS16550_init
4461 and NS16550_putc functions for the serial driver located at
4462 drivers/serial/ns16550.c. This option is useful for saving
4463 space for already greatly restricted images, including but not
4464 limited to NAND_SPL configurations.
4466 - CONFIG_DISPLAY_BOARDINFO
4467 Display information about the board that U-Boot is running on
4468 when U-Boot starts up. The board function checkboard() is called
4471 - CONFIG_DISPLAY_BOARDINFO_LATE
4472 Similar to the previous option, but display this information
4473 later, once stdio is running and output goes to the LCD, if
4476 - CONFIG_BOARD_SIZE_LIMIT:
4477 Maximum size of the U-Boot image. When defined, the
4478 build system checks that the actual size does not
4481 Low Level (hardware related) configuration options:
4482 ---------------------------------------------------
4484 - CONFIG_SYS_CACHELINE_SIZE:
4485 Cache Line Size of the CPU.
4487 - CONFIG_SYS_DEFAULT_IMMR:
4488 Default address of the IMMR after system reset.
4490 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4491 and RPXsuper) to be able to adjust the position of
4492 the IMMR register after a reset.
4494 - CONFIG_SYS_CCSRBAR_DEFAULT:
4495 Default (power-on reset) physical address of CCSR on Freescale
4498 - CONFIG_SYS_CCSRBAR:
4499 Virtual address of CCSR. On a 32-bit build, this is typically
4500 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4502 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4503 for cross-platform code that uses that macro instead.
4505 - CONFIG_SYS_CCSRBAR_PHYS:
4506 Physical address of CCSR. CCSR can be relocated to a new
4507 physical address, if desired. In this case, this macro should
4508 be set to that address. Otherwise, it should be set to the
4509 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4510 is typically relocated on 36-bit builds. It is recommended
4511 that this macro be defined via the _HIGH and _LOW macros:
4513 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4514 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4516 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4517 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4518 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4519 used in assembly code, so it must not contain typecasts or
4520 integer size suffixes (e.g. "ULL").
4522 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4523 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4524 used in assembly code, so it must not contain typecasts or
4525 integer size suffixes (e.g. "ULL").
4527 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4528 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4529 forced to a value that ensures that CCSR is not relocated.
4531 - Floppy Disk Support:
4532 CONFIG_SYS_FDC_DRIVE_NUMBER
4534 the default drive number (default value 0)
4536 CONFIG_SYS_ISA_IO_STRIDE
4538 defines the spacing between FDC chipset registers
4541 CONFIG_SYS_ISA_IO_OFFSET
4543 defines the offset of register from address. It
4544 depends on which part of the data bus is connected to
4545 the FDC chipset. (default value 0)
4547 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4548 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4551 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4552 fdc_hw_init() is called at the beginning of the FDC
4553 setup. fdc_hw_init() must be provided by the board
4554 source code. It is used to make hardware dependant
4558 Most IDE controllers were designed to be connected with PCI
4559 interface. Only few of them were designed for AHB interface.
4560 When software is doing ATA command and data transfer to
4561 IDE devices through IDE-AHB controller, some additional
4562 registers accessing to these kind of IDE-AHB controller
4565 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4566 DO NOT CHANGE unless you know exactly what you're
4567 doing! (11-4) [MPC8xx/82xx systems only]
4569 - CONFIG_SYS_INIT_RAM_ADDR:
4571 Start address of memory area that can be used for
4572 initial data and stack; please note that this must be
4573 writable memory that is working WITHOUT special
4574 initialization, i. e. you CANNOT use normal RAM which
4575 will become available only after programming the
4576 memory controller and running certain initialization
4579 U-Boot uses the following memory types:
4580 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4581 - MPC824X: data cache
4582 - PPC4xx: data cache
4584 - CONFIG_SYS_GBL_DATA_OFFSET:
4586 Offset of the initial data structure in the memory
4587 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4588 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4589 data is located at the end of the available space
4590 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4591 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4592 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4593 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4596 On the MPC824X (or other systems that use the data
4597 cache for initial memory) the address chosen for
4598 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4599 point to an otherwise UNUSED address space between
4600 the top of RAM and the start of the PCI space.
4602 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4604 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4606 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4608 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4610 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4612 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4614 - CONFIG_SYS_OR_TIMING_SDRAM:
4617 - CONFIG_SYS_MAMR_PTA:
4618 periodic timer for refresh
4620 - CONFIG_SYS_DER: Debug Event Register (37-47)
4622 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4623 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4624 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4625 CONFIG_SYS_BR1_PRELIM:
4626 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4628 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4629 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4630 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4631 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4633 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4634 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4635 Machine Mode Register and Memory Periodic Timer
4636 Prescaler definitions (SDRAM timing)
4638 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4639 enable I2C microcode relocation patch (MPC8xx);
4640 define relocation offset in DPRAM [DSP2]
4642 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4643 enable SMC microcode relocation patch (MPC8xx);
4644 define relocation offset in DPRAM [SMC1]
4646 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4647 enable SPI microcode relocation patch (MPC8xx);
4648 define relocation offset in DPRAM [SCC4]
4650 - CONFIG_SYS_USE_OSCCLK:
4651 Use OSCM clock mode on MBX8xx board. Be careful,
4652 wrong setting might damage your board. Read
4653 doc/README.MBX before setting this variable!
4655 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4656 Offset of the bootmode word in DPRAM used by post
4657 (Power On Self Tests). This definition overrides
4658 #define'd default value in commproc.h resp.
4661 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4662 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4663 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4664 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4665 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4666 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4667 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4668 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4669 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4671 - CONFIG_PCI_DISABLE_PCIE:
4672 Disable PCI-Express on systems where it is supported but not
4675 - CONFIG_PCI_ENUM_ONLY
4676 Only scan through and get the devices on the busses.
4677 Don't do any setup work, presumably because someone or
4678 something has already done it, and we don't need to do it
4679 a second time. Useful for platforms that are pre-booted
4680 by coreboot or similar.
4682 - CONFIG_PCI_INDIRECT_BRIDGE:
4683 Enable support for indirect PCI bridges.
4686 Chip has SRIO or not
4689 Board has SRIO 1 port available
4692 Board has SRIO 2 port available
4694 - CONFIG_SRIO_PCIE_BOOT_MASTER
4695 Board can support master function for Boot from SRIO and PCIE
4697 - CONFIG_SYS_SRIOn_MEM_VIRT:
4698 Virtual Address of SRIO port 'n' memory region
4700 - CONFIG_SYS_SRIOn_MEM_PHYS:
4701 Physical Address of SRIO port 'n' memory region
4703 - CONFIG_SYS_SRIOn_MEM_SIZE:
4704 Size of SRIO port 'n' memory region
4706 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4707 Defined to tell the NAND controller that the NAND chip is using
4709 Not all NAND drivers use this symbol.
4710 Example of drivers that use it:
4711 - drivers/mtd/nand/ndfc.c
4712 - drivers/mtd/nand/mxc_nand.c
4714 - CONFIG_SYS_NDFC_EBC0_CFG
4715 Sets the EBC0_CFG register for the NDFC. If not defined
4716 a default value will be used.
4719 Get DDR timing information from an I2C EEPROM. Common
4720 with pluggable memory modules such as SODIMMs
4723 I2C address of the SPD EEPROM
4725 - CONFIG_SYS_SPD_BUS_NUM
4726 If SPD EEPROM is on an I2C bus other than the first
4727 one, specify here. Note that the value must resolve
4728 to something your driver can deal with.
4730 - CONFIG_SYS_DDR_RAW_TIMING
4731 Get DDR timing information from other than SPD. Common with
4732 soldered DDR chips onboard without SPD. DDR raw timing
4733 parameters are extracted from datasheet and hard-coded into
4734 header files or board specific files.
4736 - CONFIG_FSL_DDR_INTERACTIVE
4737 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4739 - CONFIG_SYS_83XX_DDR_USES_CS0
4740 Only for 83xx systems. If specified, then DDR should
4741 be configured using CS0 and CS1 instead of CS2 and CS3.
4743 - CONFIG_ETHER_ON_FEC[12]
4744 Define to enable FEC[12] on a 8xx series processor.
4746 - CONFIG_FEC[12]_PHY
4747 Define to the hardcoded PHY address which corresponds
4748 to the given FEC; i. e.
4749 #define CONFIG_FEC1_PHY 4
4750 means that the PHY with address 4 is connected to FEC1
4752 When set to -1, means to probe for first available.
4754 - CONFIG_FEC[12]_PHY_NORXERR
4755 The PHY does not have a RXERR line (RMII only).
4756 (so program the FEC to ignore it).
4759 Enable RMII mode for all FECs.
4760 Note that this is a global option, we can't
4761 have one FEC in standard MII mode and another in RMII mode.
4763 - CONFIG_CRC32_VERIFY
4764 Add a verify option to the crc32 command.
4767 => crc32 -v <address> <count> <crc32>
4769 Where address/count indicate a memory area
4770 and crc32 is the correct crc32 which the
4774 Add the "loopw" memory command. This only takes effect if
4775 the memory commands are activated globally (CONFIG_CMD_MEM).
4778 Add the "mdc" and "mwc" memory commands. These are cyclic
4783 This command will print 4 bytes (10,11,12,13) each 500 ms.
4785 => mwc.l 100 12345678 10
4786 This command will write 12345678 to address 100 all 10 ms.
4788 This only takes effect if the memory commands are activated
4789 globally (CONFIG_CMD_MEM).
4791 - CONFIG_SKIP_LOWLEVEL_INIT
4792 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4793 low level initializations (like setting up the memory
4794 controller) are omitted and/or U-Boot does not
4795 relocate itself into RAM.
4797 Normally this variable MUST NOT be defined. The only
4798 exception is when U-Boot is loaded (to RAM) by some
4799 other boot loader or by a debugger which performs
4800 these initializations itself.
4803 Modifies the behaviour of start.S when compiling a loader
4804 that is executed before the actual U-Boot. E.g. when
4805 compiling a NAND SPL.
4808 Modifies the behaviour of start.S when compiling a loader
4809 that is executed after the SPL and before the actual U-Boot.
4810 It is loaded by the SPL.
4812 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4813 Only for 85xx systems. If this variable is specified, the section
4814 .resetvec is not kept and the section .bootpg is placed in the
4815 previous 4k of the .text section.
4817 - CONFIG_ARCH_MAP_SYSMEM
4818 Generally U-Boot (and in particular the md command) uses
4819 effective address. It is therefore not necessary to regard
4820 U-Boot address as virtual addresses that need to be translated
4821 to physical addresses. However, sandbox requires this, since
4822 it maintains its own little RAM buffer which contains all
4823 addressable memory. This option causes some memory accesses
4824 to be mapped through map_sysmem() / unmap_sysmem().
4826 - CONFIG_USE_ARCH_MEMCPY
4827 CONFIG_USE_ARCH_MEMSET
4828 If these options are used a optimized version of memcpy/memset will
4829 be used if available. These functions may be faster under some
4830 conditions but may increase the binary size.
4832 - CONFIG_X86_RESET_VECTOR
4833 If defined, the x86 reset vector code is included. This is not
4834 needed when U-Boot is running from Coreboot.
4837 Defines the MPU clock speed (in MHz).
4839 NOTE : currently only supported on AM335x platforms.
4841 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4842 Enables the RTC32K OSC on AM33xx based plattforms
4844 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
4845 Option to disable subpage write in NAND driver
4846 driver that uses this:
4847 drivers/mtd/nand/davinci_nand.c
4849 Freescale QE/FMAN Firmware Support:
4850 -----------------------------------
4852 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4853 loading of "firmware", which is encoded in the QE firmware binary format.
4854 This firmware often needs to be loaded during U-Boot booting, so macros
4855 are used to identify the storage device (NOR flash, SPI, etc) and the address
4858 - CONFIG_SYS_FMAN_FW_ADDR
4859 The address in the storage device where the FMAN microcode is located. The
4860 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4863 - CONFIG_SYS_QE_FW_ADDR
4864 The address in the storage device where the QE microcode is located. The
4865 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4868 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4869 The maximum possible size of the firmware. The firmware binary format
4870 has a field that specifies the actual size of the firmware, but it
4871 might not be possible to read any part of the firmware unless some
4872 local storage is allocated to hold the entire firmware first.
4874 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4875 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4876 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4877 virtual address in NOR flash.
4879 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4880 Specifies that QE/FMAN firmware is located in NAND flash.
4881 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4883 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4884 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4885 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4887 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4888 Specifies that QE/FMAN firmware is located on the primary SPI
4889 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4891 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4892 Specifies that QE/FMAN firmware is located in the remote (master)
4893 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4894 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4895 window->master inbound window->master LAW->the ucode address in
4896 master's memory space.
4898 Freescale Layerscape Management Complex Firmware Support:
4899 ---------------------------------------------------------
4900 The Freescale Layerscape Management Complex (MC) supports the loading of
4902 This firmware often needs to be loaded during U-Boot booting, so macros
4903 are used to identify the storage device (NOR flash, SPI, etc) and the address
4906 - CONFIG_FSL_MC_ENET
4907 Enable the MC driver for Layerscape SoCs.
4909 - CONFIG_SYS_LS_MC_FW_ADDR
4910 The address in the storage device where the firmware is located. The
4911 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
4914 - CONFIG_SYS_LS_MC_FW_LENGTH
4915 The maximum possible size of the firmware. The firmware binary format
4916 has a field that specifies the actual size of the firmware, but it
4917 might not be possible to read any part of the firmware unless some
4918 local storage is allocated to hold the entire firmware first.
4920 - CONFIG_SYS_LS_MC_FW_IN_NOR
4921 Specifies that MC firmware is located in NOR flash, mapped as
4922 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
4923 virtual address in NOR flash.
4925 Building the Software:
4926 ======================
4928 Building U-Boot has been tested in several native build environments
4929 and in many different cross environments. Of course we cannot support
4930 all possibly existing versions of cross development tools in all
4931 (potentially obsolete) versions. In case of tool chain problems we
4932 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4933 which is extensively used to build and test U-Boot.
4935 If you are not using a native environment, it is assumed that you
4936 have GNU cross compiling tools available in your path. In this case,
4937 you must set the environment variable CROSS_COMPILE in your shell.
4938 Note that no changes to the Makefile or any other source files are
4939 necessary. For example using the ELDK on a 4xx CPU, please enter:
4941 $ CROSS_COMPILE=ppc_4xx-
4942 $ export CROSS_COMPILE
4944 Note: If you wish to generate Windows versions of the utilities in
4945 the tools directory you can use the MinGW toolchain
4946 (http://www.mingw.org). Set your HOST tools to the MinGW
4947 toolchain and execute 'make tools'. For example:
4949 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4951 Binaries such as tools/mkimage.exe will be created which can
4952 be executed on computers running Windows.
4954 U-Boot is intended to be simple to build. After installing the
4955 sources you must configure U-Boot for one specific board type. This
4960 where "NAME_defconfig" is the name of one of the existing configu-
4961 rations; see boards.cfg for supported names.
4963 Note: for some board special configuration names may exist; check if
4964 additional information is available from the board vendor; for
4965 instance, the TQM823L systems are available without (standard)
4966 or with LCD support. You can select such additional "features"
4967 when choosing the configuration, i. e.
4969 make TQM823L_defconfig
4970 - will configure for a plain TQM823L, i. e. no LCD support
4972 make TQM823L_LCD_defconfig
4973 - will configure for a TQM823L with U-Boot console on LCD
4978 Finally, type "make all", and you should get some working U-Boot
4979 images ready for download to / installation on your system:
4981 - "u-boot.bin" is a raw binary image
4982 - "u-boot" is an image in ELF binary format
4983 - "u-boot.srec" is in Motorola S-Record format
4985 By default the build is performed locally and the objects are saved
4986 in the source directory. One of the two methods can be used to change
4987 this behavior and build U-Boot to some external directory:
4989 1. Add O= to the make command line invocations:
4991 make O=/tmp/build distclean
4992 make O=/tmp/build NAME_defconfig
4993 make O=/tmp/build all
4995 2. Set environment variable BUILD_DIR to point to the desired location:
4997 export BUILD_DIR=/tmp/build
5002 Note that the command line "O=" setting overrides the BUILD_DIR environment
5006 Please be aware that the Makefiles assume you are using GNU make, so
5007 for instance on NetBSD you might need to use "gmake" instead of
5011 If the system board that you have is not listed, then you will need
5012 to port U-Boot to your hardware platform. To do this, follow these
5015 1. Add a new configuration option for your board to the toplevel
5016 "boards.cfg" file, using the existing entries as examples.
5017 Follow the instructions there to keep the boards in order.
5018 2. Create a new directory to hold your board specific code. Add any
5019 files you need. In your board directory, you will need at least
5020 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
5021 3. Create a new configuration file "include/configs/<board>.h" for
5023 3. If you're porting U-Boot to a new CPU, then also create a new
5024 directory to hold your CPU specific code. Add any files you need.
5025 4. Run "make <board>_defconfig" with your new name.
5026 5. Type "make", and you should get a working "u-boot.srec" file
5027 to be installed on your target system.
5028 6. Debug and solve any problems that might arise.
5029 [Of course, this last step is much harder than it sounds.]
5032 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
5033 ==============================================================
5035 If you have modified U-Boot sources (for instance added a new board
5036 or support for new devices, a new CPU, etc.) you are expected to
5037 provide feedback to the other developers. The feedback normally takes
5038 the form of a "patch", i. e. a context diff against a certain (latest
5039 official or latest in the git repository) version of U-Boot sources.
5041 But before you submit such a patch, please verify that your modifi-
5042 cation did not break existing code. At least make sure that *ALL* of
5043 the supported boards compile WITHOUT ANY compiler warnings. To do so,
5044 just run the "MAKEALL" script, which will configure and build U-Boot
5045 for ALL supported system. Be warned, this will take a while. You can
5046 select which (cross) compiler to use by passing a `CROSS_COMPILE'
5047 environment variable to the script, i. e. to use the ELDK cross tools
5050 CROSS_COMPILE=ppc_8xx- MAKEALL
5052 or to build on a native PowerPC system you can type
5054 CROSS_COMPILE=' ' MAKEALL
5056 When using the MAKEALL script, the default behaviour is to build
5057 U-Boot in the source directory. This location can be changed by
5058 setting the BUILD_DIR environment variable. Also, for each target
5059 built, the MAKEALL script saves two log files (<target>.ERR and
5060 <target>.MAKEALL) in the <source dir>/LOG directory. This default
5061 location can be changed by setting the MAKEALL_LOGDIR environment
5062 variable. For example:
5064 export BUILD_DIR=/tmp/build
5065 export MAKEALL_LOGDIR=/tmp/log
5066 CROSS_COMPILE=ppc_8xx- MAKEALL
5068 With the above settings build objects are saved in the /tmp/build,
5069 log files are saved in the /tmp/log and the source tree remains clean
5070 during the whole build process.
5073 See also "U-Boot Porting Guide" below.
5076 Monitor Commands - Overview:
5077 ============================
5079 go - start application at address 'addr'
5080 run - run commands in an environment variable
5081 bootm - boot application image from memory
5082 bootp - boot image via network using BootP/TFTP protocol
5083 bootz - boot zImage from memory
5084 tftpboot- boot image via network using TFTP protocol
5085 and env variables "ipaddr" and "serverip"
5086 (and eventually "gatewayip")
5087 tftpput - upload a file via network using TFTP protocol
5088 rarpboot- boot image via network using RARP/TFTP protocol
5089 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
5090 loads - load S-Record file over serial line
5091 loadb - load binary file over serial line (kermit mode)
5093 mm - memory modify (auto-incrementing)
5094 nm - memory modify (constant address)
5095 mw - memory write (fill)
5097 cmp - memory compare
5098 crc32 - checksum calculation
5099 i2c - I2C sub-system
5100 sspi - SPI utility commands
5101 base - print or set address offset
5102 printenv- print environment variables
5103 setenv - set environment variables
5104 saveenv - save environment variables to persistent storage
5105 protect - enable or disable FLASH write protection
5106 erase - erase FLASH memory
5107 flinfo - print FLASH memory information
5108 nand - NAND memory operations (see doc/README.nand)
5109 bdinfo - print Board Info structure
5110 iminfo - print header information for application image
5111 coninfo - print console devices and informations
5112 ide - IDE sub-system
5113 loop - infinite loop on address range
5114 loopw - infinite write loop on address range
5115 mtest - simple RAM test
5116 icache - enable or disable instruction cache
5117 dcache - enable or disable data cache
5118 reset - Perform RESET of the CPU
5119 echo - echo args to console
5120 version - print monitor version
5121 help - print online help
5122 ? - alias for 'help'
5125 Monitor Commands - Detailed Description:
5126 ========================================
5130 For now: just type "help <command>".
5133 Environment Variables:
5134 ======================
5136 U-Boot supports user configuration using Environment Variables which
5137 can be made persistent by saving to Flash memory.
5139 Environment Variables are set using "setenv", printed using
5140 "printenv", and saved to Flash using "saveenv". Using "setenv"
5141 without a value can be used to delete a variable from the
5142 environment. As long as you don't save the environment you are
5143 working with an in-memory copy. In case the Flash area containing the
5144 environment is erased by accident, a default environment is provided.
5146 Some configuration options can be set using Environment Variables.
5148 List of environment variables (most likely not complete):
5150 baudrate - see CONFIG_BAUDRATE
5152 bootdelay - see CONFIG_BOOTDELAY
5154 bootcmd - see CONFIG_BOOTCOMMAND
5156 bootargs - Boot arguments when booting an RTOS image
5158 bootfile - Name of the image to load with TFTP
5160 bootm_low - Memory range available for image processing in the bootm
5161 command can be restricted. This variable is given as
5162 a hexadecimal number and defines lowest address allowed
5163 for use by the bootm command. See also "bootm_size"
5164 environment variable. Address defined by "bootm_low" is
5165 also the base of the initial memory mapping for the Linux
5166 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
5169 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
5170 This variable is given as a hexadecimal number and it
5171 defines the size of the memory region starting at base
5172 address bootm_low that is accessible by the Linux kernel
5173 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
5174 as the default value if it is defined, and bootm_size is
5177 bootm_size - Memory range available for image processing in the bootm
5178 command can be restricted. This variable is given as
5179 a hexadecimal number and defines the size of the region
5180 allowed for use by the bootm command. See also "bootm_low"
5181 environment variable.
5183 updatefile - Location of the software update file on a TFTP server, used
5184 by the automatic software update feature. Please refer to
5185 documentation in doc/README.update for more details.
5187 autoload - if set to "no" (any string beginning with 'n'),
5188 "bootp" will just load perform a lookup of the
5189 configuration from the BOOTP server, but not try to
5190 load any image using TFTP
5192 autostart - if set to "yes", an image loaded using the "bootp",
5193 "rarpboot", "tftpboot" or "diskboot" commands will
5194 be automatically started (by internally calling
5197 If set to "no", a standalone image passed to the
5198 "bootm" command will be copied to the load address
5199 (and eventually uncompressed), but NOT be started.
5200 This can be used to load and uncompress arbitrary
5203 fdt_high - if set this restricts the maximum address that the
5204 flattened device tree will be copied into upon boot.
5205 For example, if you have a system with 1 GB memory
5206 at physical address 0x10000000, while Linux kernel
5207 only recognizes the first 704 MB as low memory, you
5208 may need to set fdt_high as 0x3C000000 to have the
5209 device tree blob be copied to the maximum address
5210 of the 704 MB low memory, so that Linux kernel can
5211 access it during the boot procedure.
5213 If this is set to the special value 0xFFFFFFFF then
5214 the fdt will not be copied at all on boot. For this
5215 to work it must reside in writable memory, have
5216 sufficient padding on the end of it for u-boot to
5217 add the information it needs into it, and the memory
5218 must be accessible by the kernel.
5220 fdtcontroladdr- if set this is the address of the control flattened
5221 device tree used by U-Boot when CONFIG_OF_CONTROL is
5224 i2cfast - (PPC405GP|PPC405EP only)
5225 if set to 'y' configures Linux I2C driver for fast
5226 mode (400kHZ). This environment variable is used in
5227 initialization code. So, for changes to be effective
5228 it must be saved and board must be reset.
5230 initrd_high - restrict positioning of initrd images:
5231 If this variable is not set, initrd images will be
5232 copied to the highest possible address in RAM; this
5233 is usually what you want since it allows for
5234 maximum initrd size. If for some reason you want to
5235 make sure that the initrd image is loaded below the
5236 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
5237 variable to a value of "no" or "off" or "0".
5238 Alternatively, you can set it to a maximum upper
5239 address to use (U-Boot will still check that it
5240 does not overwrite the U-Boot stack and data).
5242 For instance, when you have a system with 16 MB
5243 RAM, and want to reserve 4 MB from use by Linux,
5244 you can do this by adding "mem=12M" to the value of
5245 the "bootargs" variable. However, now you must make
5246 sure that the initrd image is placed in the first
5247 12 MB as well - this can be done with
5249 setenv initrd_high 00c00000
5251 If you set initrd_high to 0xFFFFFFFF, this is an
5252 indication to U-Boot that all addresses are legal
5253 for the Linux kernel, including addresses in flash
5254 memory. In this case U-Boot will NOT COPY the
5255 ramdisk at all. This may be useful to reduce the
5256 boot time on your system, but requires that this
5257 feature is supported by your Linux kernel.
5259 ipaddr - IP address; needed for tftpboot command
5261 loadaddr - Default load address for commands like "bootp",
5262 "rarpboot", "tftpboot", "loadb" or "diskboot"
5264 loads_echo - see CONFIG_LOADS_ECHO
5266 serverip - TFTP server IP address; needed for tftpboot command
5268 bootretry - see CONFIG_BOOT_RETRY_TIME
5270 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
5272 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
5274 ethprime - controls which interface is used first.
5276 ethact - controls which interface is currently active.
5277 For example you can do the following
5279 => setenv ethact FEC
5280 => ping 192.168.0.1 # traffic sent on FEC
5281 => setenv ethact SCC
5282 => ping 10.0.0.1 # traffic sent on SCC
5284 ethrotate - When set to "no" U-Boot does not go through all
5285 available network interfaces.
5286 It just stays at the currently selected interface.
5288 netretry - When set to "no" each network operation will
5289 either succeed or fail without retrying.
5290 When set to "once" the network operation will
5291 fail when all the available network interfaces
5292 are tried once without success.
5293 Useful on scripts which control the retry operation
5296 npe_ucode - set load address for the NPE microcode
5298 silent_linux - If set then linux will be told to boot silently, by
5299 changing the console to be empty. If "yes" it will be
5300 made silent. If "no" it will not be made silent. If
5301 unset, then it will be made silent if the U-Boot console
5304 tftpsrcport - If this is set, the value is used for TFTP's
5307 tftpdstport - If this is set, the value is used for TFTP's UDP
5308 destination port instead of the Well Know Port 69.
5310 tftpblocksize - Block size to use for TFTP transfers; if not set,
5311 we use the TFTP server's default block size
5313 tftptimeout - Retransmission timeout for TFTP packets (in milli-
5314 seconds, minimum value is 1000 = 1 second). Defines
5315 when a packet is considered to be lost so it has to
5316 be retransmitted. The default is 5000 = 5 seconds.
5317 Lowering this value may make downloads succeed
5318 faster in networks with high packet loss rates or
5319 with unreliable TFTP servers.
5321 vlan - When set to a value < 4095 the traffic over
5322 Ethernet is encapsulated/received over 802.1q
5325 The following image location variables contain the location of images
5326 used in booting. The "Image" column gives the role of the image and is
5327 not an environment variable name. The other columns are environment
5328 variable names. "File Name" gives the name of the file on a TFTP
5329 server, "RAM Address" gives the location in RAM the image will be
5330 loaded to, and "Flash Location" gives the image's address in NOR
5331 flash or offset in NAND flash.
5333 *Note* - these variables don't have to be defined for all boards, some
5334 boards currenlty use other variables for these purposes, and some
5335 boards use these variables for other purposes.
5337 Image File Name RAM Address Flash Location
5338 ----- --------- ----------- --------------
5339 u-boot u-boot u-boot_addr_r u-boot_addr
5340 Linux kernel bootfile kernel_addr_r kernel_addr
5341 device tree blob fdtfile fdt_addr_r fdt_addr
5342 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
5344 The following environment variables may be used and automatically
5345 updated by the network boot commands ("bootp" and "rarpboot"),
5346 depending the information provided by your boot server:
5348 bootfile - see above
5349 dnsip - IP address of your Domain Name Server
5350 dnsip2 - IP address of your secondary Domain Name Server
5351 gatewayip - IP address of the Gateway (Router) to use
5352 hostname - Target hostname
5354 netmask - Subnet Mask
5355 rootpath - Pathname of the root filesystem on the NFS server
5356 serverip - see above
5359 There are two special Environment Variables:
5361 serial# - contains hardware identification information such
5362 as type string and/or serial number
5363 ethaddr - Ethernet address
5365 These variables can be set only once (usually during manufacturing of
5366 the board). U-Boot refuses to delete or overwrite these variables
5367 once they have been set once.
5370 Further special Environment Variables:
5372 ver - Contains the U-Boot version string as printed
5373 with the "version" command. This variable is
5374 readonly (see CONFIG_VERSION_VARIABLE).
5377 Please note that changes to some configuration parameters may take
5378 only effect after the next boot (yes, that's just like Windoze :-).
5381 Callback functions for environment variables:
5382 ---------------------------------------------
5384 For some environment variables, the behavior of u-boot needs to change
5385 when their values are changed. This functionailty allows functions to
5386 be associated with arbitrary variables. On creation, overwrite, or
5387 deletion, the callback will provide the opportunity for some side
5388 effect to happen or for the change to be rejected.
5390 The callbacks are named and associated with a function using the
5391 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5393 These callbacks are associated with variables in one of two ways. The
5394 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5395 in the board configuration to a string that defines a list of
5396 associations. The list must be in the following format:
5398 entry = variable_name[:callback_name]
5401 If the callback name is not specified, then the callback is deleted.
5402 Spaces are also allowed anywhere in the list.
5404 Callbacks can also be associated by defining the ".callbacks" variable
5405 with the same list format above. Any association in ".callbacks" will
5406 override any association in the static list. You can define
5407 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5408 ".callbacks" envirnoment variable in the default or embedded environment.
5411 Command Line Parsing:
5412 =====================
5414 There are two different command line parsers available with U-Boot:
5415 the old "simple" one, and the much more powerful "hush" shell:
5417 Old, simple command line parser:
5418 --------------------------------
5420 - supports environment variables (through setenv / saveenv commands)
5421 - several commands on one line, separated by ';'
5422 - variable substitution using "... ${name} ..." syntax
5423 - special characters ('$', ';') can be escaped by prefixing with '\',
5425 setenv bootcmd bootm \${address}
5426 - You can also escape text by enclosing in single apostrophes, for example:
5427 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5432 - similar to Bourne shell, with control structures like
5433 if...then...else...fi, for...do...done; while...do...done,
5434 until...do...done, ...
5435 - supports environment ("global") variables (through setenv / saveenv
5436 commands) and local shell variables (through standard shell syntax
5437 "name=value"); only environment variables can be used with "run"
5443 (1) If a command line (or an environment variable executed by a "run"
5444 command) contains several commands separated by semicolon, and
5445 one of these commands fails, then the remaining commands will be
5448 (2) If you execute several variables with one call to run (i. e.
5449 calling run with a list of variables as arguments), any failing
5450 command will cause "run" to terminate, i. e. the remaining
5451 variables are not executed.
5453 Note for Redundant Ethernet Interfaces:
5454 =======================================
5456 Some boards come with redundant Ethernet interfaces; U-Boot supports
5457 such configurations and is capable of automatic selection of a
5458 "working" interface when needed. MAC assignment works as follows:
5460 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5461 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5462 "eth1addr" (=>eth1), "eth2addr", ...
5464 If the network interface stores some valid MAC address (for instance
5465 in SROM), this is used as default address if there is NO correspon-
5466 ding setting in the environment; if the corresponding environment
5467 variable is set, this overrides the settings in the card; that means:
5469 o If the SROM has a valid MAC address, and there is no address in the
5470 environment, the SROM's address is used.
5472 o If there is no valid address in the SROM, and a definition in the
5473 environment exists, then the value from the environment variable is
5476 o If both the SROM and the environment contain a MAC address, and
5477 both addresses are the same, this MAC address is used.
5479 o If both the SROM and the environment contain a MAC address, and the
5480 addresses differ, the value from the environment is used and a
5483 o If neither SROM nor the environment contain a MAC address, an error
5486 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5487 will be programmed into hardware as part of the initialization process. This
5488 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5489 The naming convention is as follows:
5490 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5495 U-Boot is capable of booting (and performing other auxiliary operations on)
5496 images in two formats:
5498 New uImage format (FIT)
5499 -----------------------
5501 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5502 to Flattened Device Tree). It allows the use of images with multiple
5503 components (several kernels, ramdisks, etc.), with contents protected by
5504 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5510 Old image format is based on binary files which can be basically anything,
5511 preceded by a special header; see the definitions in include/image.h for
5512 details; basically, the header defines the following image properties:
5514 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5515 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5516 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5517 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5519 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5520 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5521 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5522 * Compression Type (uncompressed, gzip, bzip2)
5528 The header is marked by a special Magic Number, and both the header
5529 and the data portions of the image are secured against corruption by
5536 Although U-Boot should support any OS or standalone application
5537 easily, the main focus has always been on Linux during the design of
5540 U-Boot includes many features that so far have been part of some
5541 special "boot loader" code within the Linux kernel. Also, any
5542 "initrd" images to be used are no longer part of one big Linux image;
5543 instead, kernel and "initrd" are separate images. This implementation
5544 serves several purposes:
5546 - the same features can be used for other OS or standalone
5547 applications (for instance: using compressed images to reduce the
5548 Flash memory footprint)
5550 - it becomes much easier to port new Linux kernel versions because
5551 lots of low-level, hardware dependent stuff are done by U-Boot
5553 - the same Linux kernel image can now be used with different "initrd"
5554 images; of course this also means that different kernel images can
5555 be run with the same "initrd". This makes testing easier (you don't
5556 have to build a new "zImage.initrd" Linux image when you just
5557 change a file in your "initrd"). Also, a field-upgrade of the
5558 software is easier now.
5564 Porting Linux to U-Boot based systems:
5565 ---------------------------------------
5567 U-Boot cannot save you from doing all the necessary modifications to
5568 configure the Linux device drivers for use with your target hardware
5569 (no, we don't intend to provide a full virtual machine interface to
5572 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5574 Just make sure your machine specific header file (for instance
5575 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5576 Information structure as we define in include/asm-<arch>/u-boot.h,
5577 and make sure that your definition of IMAP_ADDR uses the same value
5578 as your U-Boot configuration in CONFIG_SYS_IMMR.
5580 Note that U-Boot now has a driver model, a unified model for drivers.
5581 If you are adding a new driver, plumb it into driver model. If there
5582 is no uclass available, you are encouraged to create one. See
5586 Configuring the Linux kernel:
5587 -----------------------------
5589 No specific requirements for U-Boot. Make sure you have some root
5590 device (initial ramdisk, NFS) for your target system.
5593 Building a Linux Image:
5594 -----------------------
5596 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5597 not used. If you use recent kernel source, a new build target
5598 "uImage" will exist which automatically builds an image usable by
5599 U-Boot. Most older kernels also have support for a "pImage" target,
5600 which was introduced for our predecessor project PPCBoot and uses a
5601 100% compatible format.
5605 make TQM850L_defconfig
5610 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5611 encapsulate a compressed Linux kernel image with header information,
5612 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5614 * build a standard "vmlinux" kernel image (in ELF binary format):
5616 * convert the kernel into a raw binary image:
5618 ${CROSS_COMPILE}-objcopy -O binary \
5619 -R .note -R .comment \
5620 -S vmlinux linux.bin
5622 * compress the binary image:
5626 * package compressed binary image for U-Boot:
5628 mkimage -A ppc -O linux -T kernel -C gzip \
5629 -a 0 -e 0 -n "Linux Kernel Image" \
5630 -d linux.bin.gz uImage
5633 The "mkimage" tool can also be used to create ramdisk images for use
5634 with U-Boot, either separated from the Linux kernel image, or
5635 combined into one file. "mkimage" encapsulates the images with a 64
5636 byte header containing information about target architecture,
5637 operating system, image type, compression method, entry points, time
5638 stamp, CRC32 checksums, etc.
5640 "mkimage" can be called in two ways: to verify existing images and
5641 print the header information, or to build new images.
5643 In the first form (with "-l" option) mkimage lists the information
5644 contained in the header of an existing U-Boot image; this includes
5645 checksum verification:
5647 tools/mkimage -l image
5648 -l ==> list image header information
5650 The second form (with "-d" option) is used to build a U-Boot image
5651 from a "data file" which is used as image payload:
5653 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5654 -n name -d data_file image
5655 -A ==> set architecture to 'arch'
5656 -O ==> set operating system to 'os'
5657 -T ==> set image type to 'type'
5658 -C ==> set compression type 'comp'
5659 -a ==> set load address to 'addr' (hex)
5660 -e ==> set entry point to 'ep' (hex)
5661 -n ==> set image name to 'name'
5662 -d ==> use image data from 'datafile'
5664 Right now, all Linux kernels for PowerPC systems use the same load
5665 address (0x00000000), but the entry point address depends on the
5668 - 2.2.x kernels have the entry point at 0x0000000C,
5669 - 2.3.x and later kernels have the entry point at 0x00000000.
5671 So a typical call to build a U-Boot image would read:
5673 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5674 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5675 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5676 > examples/uImage.TQM850L
5677 Image Name: 2.4.4 kernel for TQM850L
5678 Created: Wed Jul 19 02:34:59 2000
5679 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5680 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5681 Load Address: 0x00000000
5682 Entry Point: 0x00000000
5684 To verify the contents of the image (or check for corruption):
5686 -> tools/mkimage -l examples/uImage.TQM850L
5687 Image Name: 2.4.4 kernel for TQM850L
5688 Created: Wed Jul 19 02:34:59 2000
5689 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5690 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5691 Load Address: 0x00000000
5692 Entry Point: 0x00000000
5694 NOTE: for embedded systems where boot time is critical you can trade
5695 speed for memory and install an UNCOMPRESSED image instead: this
5696 needs more space in Flash, but boots much faster since it does not
5697 need to be uncompressed:
5699 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5700 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5701 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5702 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5703 > examples/uImage.TQM850L-uncompressed
5704 Image Name: 2.4.4 kernel for TQM850L
5705 Created: Wed Jul 19 02:34:59 2000
5706 Image Type: PowerPC Linux Kernel Image (uncompressed)
5707 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5708 Load Address: 0x00000000
5709 Entry Point: 0x00000000
5712 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5713 when your kernel is intended to use an initial ramdisk:
5715 -> tools/mkimage -n 'Simple Ramdisk Image' \
5716 > -A ppc -O linux -T ramdisk -C gzip \
5717 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5718 Image Name: Simple Ramdisk Image
5719 Created: Wed Jan 12 14:01:50 2000
5720 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5721 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5722 Load Address: 0x00000000
5723 Entry Point: 0x00000000
5725 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5726 option performs the converse operation of the mkimage's second form (the "-d"
5727 option). Given an image built by mkimage, the dumpimage extracts a "data file"
5730 tools/dumpimage -i image -p position data_file
5731 -i ==> extract from the 'image' a specific 'data_file', \
5732 indexed by 'position'
5735 Installing a Linux Image:
5736 -------------------------
5738 To downloading a U-Boot image over the serial (console) interface,
5739 you must convert the image to S-Record format:
5741 objcopy -I binary -O srec examples/image examples/image.srec
5743 The 'objcopy' does not understand the information in the U-Boot
5744 image header, so the resulting S-Record file will be relative to
5745 address 0x00000000. To load it to a given address, you need to
5746 specify the target address as 'offset' parameter with the 'loads'
5749 Example: install the image to address 0x40100000 (which on the
5750 TQM8xxL is in the first Flash bank):
5752 => erase 40100000 401FFFFF
5758 ## Ready for S-Record download ...
5759 ~>examples/image.srec
5760 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5762 15989 15990 15991 15992
5763 [file transfer complete]
5765 ## Start Addr = 0x00000000
5768 You can check the success of the download using the 'iminfo' command;
5769 this includes a checksum verification so you can be sure no data
5770 corruption happened:
5774 ## Checking Image at 40100000 ...
5775 Image Name: 2.2.13 for initrd on TQM850L
5776 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5777 Data Size: 335725 Bytes = 327 kB = 0 MB
5778 Load Address: 00000000
5779 Entry Point: 0000000c
5780 Verifying Checksum ... OK
5786 The "bootm" command is used to boot an application that is stored in
5787 memory (RAM or Flash). In case of a Linux kernel image, the contents
5788 of the "bootargs" environment variable is passed to the kernel as
5789 parameters. You can check and modify this variable using the
5790 "printenv" and "setenv" commands:
5793 => printenv bootargs
5794 bootargs=root=/dev/ram
5796 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5798 => printenv bootargs
5799 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5802 ## Booting Linux kernel at 40020000 ...
5803 Image Name: 2.2.13 for NFS on TQM850L
5804 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5805 Data Size: 381681 Bytes = 372 kB = 0 MB
5806 Load Address: 00000000
5807 Entry Point: 0000000c
5808 Verifying Checksum ... OK
5809 Uncompressing Kernel Image ... OK
5810 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
5811 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5812 time_init: decrementer frequency = 187500000/60
5813 Calibrating delay loop... 49.77 BogoMIPS
5814 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5817 If you want to boot a Linux kernel with initial RAM disk, you pass
5818 the memory addresses of both the kernel and the initrd image (PPBCOOT
5819 format!) to the "bootm" command:
5821 => imi 40100000 40200000
5823 ## Checking Image at 40100000 ...
5824 Image Name: 2.2.13 for initrd on TQM850L
5825 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5826 Data Size: 335725 Bytes = 327 kB = 0 MB
5827 Load Address: 00000000
5828 Entry Point: 0000000c
5829 Verifying Checksum ... OK
5831 ## Checking Image at 40200000 ...
5832 Image Name: Simple Ramdisk Image
5833 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5834 Data Size: 566530 Bytes = 553 kB = 0 MB
5835 Load Address: 00000000
5836 Entry Point: 00000000
5837 Verifying Checksum ... OK
5839 => bootm 40100000 40200000
5840 ## Booting Linux kernel at 40100000 ...
5841 Image Name: 2.2.13 for initrd on TQM850L
5842 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5843 Data Size: 335725 Bytes = 327 kB = 0 MB
5844 Load Address: 00000000
5845 Entry Point: 0000000c
5846 Verifying Checksum ... OK
5847 Uncompressing Kernel Image ... OK
5848 ## Loading RAMDisk Image at 40200000 ...
5849 Image Name: Simple Ramdisk Image
5850 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5851 Data Size: 566530 Bytes = 553 kB = 0 MB
5852 Load Address: 00000000
5853 Entry Point: 00000000
5854 Verifying Checksum ... OK
5855 Loading Ramdisk ... OK
5856 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
5857 Boot arguments: root=/dev/ram
5858 time_init: decrementer frequency = 187500000/60
5859 Calibrating delay loop... 49.77 BogoMIPS
5861 RAMDISK: Compressed image found at block 0
5862 VFS: Mounted root (ext2 filesystem).
5866 Boot Linux and pass a flat device tree:
5869 First, U-Boot must be compiled with the appropriate defines. See the section
5870 titled "Linux Kernel Interface" above for a more in depth explanation. The
5871 following is an example of how to start a kernel and pass an updated
5877 oft=oftrees/mpc8540ads.dtb
5878 => tftp $oftaddr $oft
5879 Speed: 1000, full duplex
5881 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5882 Filename 'oftrees/mpc8540ads.dtb'.
5883 Load address: 0x300000
5886 Bytes transferred = 4106 (100a hex)
5887 => tftp $loadaddr $bootfile
5888 Speed: 1000, full duplex
5890 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5892 Load address: 0x200000
5893 Loading:############
5895 Bytes transferred = 1029407 (fb51f hex)
5900 => bootm $loadaddr - $oftaddr
5901 ## Booting image at 00200000 ...
5902 Image Name: Linux-2.6.17-dirty
5903 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5904 Data Size: 1029343 Bytes = 1005.2 kB
5905 Load Address: 00000000
5906 Entry Point: 00000000
5907 Verifying Checksum ... OK
5908 Uncompressing Kernel Image ... OK
5909 Booting using flat device tree at 0x300000
5910 Using MPC85xx ADS machine description
5911 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5915 More About U-Boot Image Types:
5916 ------------------------------
5918 U-Boot supports the following image types:
5920 "Standalone Programs" are directly runnable in the environment
5921 provided by U-Boot; it is expected that (if they behave
5922 well) you can continue to work in U-Boot after return from
5923 the Standalone Program.
5924 "OS Kernel Images" are usually images of some Embedded OS which
5925 will take over control completely. Usually these programs
5926 will install their own set of exception handlers, device
5927 drivers, set up the MMU, etc. - this means, that you cannot
5928 expect to re-enter U-Boot except by resetting the CPU.
5929 "RAMDisk Images" are more or less just data blocks, and their
5930 parameters (address, size) are passed to an OS kernel that is
5932 "Multi-File Images" contain several images, typically an OS
5933 (Linux) kernel image and one or more data images like
5934 RAMDisks. This construct is useful for instance when you want
5935 to boot over the network using BOOTP etc., where the boot
5936 server provides just a single image file, but you want to get
5937 for instance an OS kernel and a RAMDisk image.
5939 "Multi-File Images" start with a list of image sizes, each
5940 image size (in bytes) specified by an "uint32_t" in network
5941 byte order. This list is terminated by an "(uint32_t)0".
5942 Immediately after the terminating 0 follow the images, one by
5943 one, all aligned on "uint32_t" boundaries (size rounded up to
5944 a multiple of 4 bytes).
5946 "Firmware Images" are binary images containing firmware (like
5947 U-Boot or FPGA images) which usually will be programmed to
5950 "Script files" are command sequences that will be executed by
5951 U-Boot's command interpreter; this feature is especially
5952 useful when you configure U-Boot to use a real shell (hush)
5953 as command interpreter.
5955 Booting the Linux zImage:
5956 -------------------------
5958 On some platforms, it's possible to boot Linux zImage. This is done
5959 using the "bootz" command. The syntax of "bootz" command is the same
5960 as the syntax of "bootm" command.
5962 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5963 kernel with raw initrd images. The syntax is slightly different, the
5964 address of the initrd must be augmented by it's size, in the following
5965 format: "<initrd addres>:<initrd size>".
5971 One of the features of U-Boot is that you can dynamically load and
5972 run "standalone" applications, which can use some resources of
5973 U-Boot like console I/O functions or interrupt services.
5975 Two simple examples are included with the sources:
5980 'examples/hello_world.c' contains a small "Hello World" Demo
5981 application; it is automatically compiled when you build U-Boot.
5982 It's configured to run at address 0x00040004, so you can play with it
5986 ## Ready for S-Record download ...
5987 ~>examples/hello_world.srec
5988 1 2 3 4 5 6 7 8 9 10 11 ...
5989 [file transfer complete]
5991 ## Start Addr = 0x00040004
5993 => go 40004 Hello World! This is a test.
5994 ## Starting application at 0x00040004 ...
6005 Hit any key to exit ...
6007 ## Application terminated, rc = 0x0
6009 Another example, which demonstrates how to register a CPM interrupt
6010 handler with the U-Boot code, can be found in 'examples/timer.c'.
6011 Here, a CPM timer is set up to generate an interrupt every second.
6012 The interrupt service routine is trivial, just printing a '.'
6013 character, but this is just a demo program. The application can be
6014 controlled by the following keys:
6016 ? - print current values og the CPM Timer registers
6017 b - enable interrupts and start timer
6018 e - stop timer and disable interrupts
6019 q - quit application
6022 ## Ready for S-Record download ...
6023 ~>examples/timer.srec
6024 1 2 3 4 5 6 7 8 9 10 11 ...
6025 [file transfer complete]
6027 ## Start Addr = 0x00040004
6030 ## Starting application at 0x00040004 ...
6033 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
6036 [q, b, e, ?] Set interval 1000000 us
6039 [q, b, e, ?] ........
6040 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
6043 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
6046 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
6049 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
6051 [q, b, e, ?] ...Stopping timer
6053 [q, b, e, ?] ## Application terminated, rc = 0x0
6059 Over time, many people have reported problems when trying to use the
6060 "minicom" terminal emulation program for serial download. I (wd)
6061 consider minicom to be broken, and recommend not to use it. Under
6062 Unix, I recommend to use C-Kermit for general purpose use (and
6063 especially for kermit binary protocol download ("loadb" command), and
6064 use "cu" for S-Record download ("loads" command). See
6065 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
6066 for help with kermit.
6069 Nevertheless, if you absolutely want to use it try adding this
6070 configuration to your "File transfer protocols" section:
6072 Name Program Name U/D FullScr IO-Red. Multi
6073 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
6074 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
6080 Starting at version 0.9.2, U-Boot supports NetBSD both as host
6081 (build U-Boot) and target system (boots NetBSD/mpc8xx).
6083 Building requires a cross environment; it is known to work on
6084 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
6085 need gmake since the Makefiles are not compatible with BSD make).
6086 Note that the cross-powerpc package does not install include files;
6087 attempting to build U-Boot will fail because <machine/ansi.h> is
6088 missing. This file has to be installed and patched manually:
6090 # cd /usr/pkg/cross/powerpc-netbsd/include
6092 # ln -s powerpc machine
6093 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
6094 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
6096 Native builds *don't* work due to incompatibilities between native
6097 and U-Boot include files.
6099 Booting assumes that (the first part of) the image booted is a
6100 stage-2 loader which in turn loads and then invokes the kernel
6101 proper. Loader sources will eventually appear in the NetBSD source
6102 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
6103 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
6106 Implementation Internals:
6107 =========================
6109 The following is not intended to be a complete description of every
6110 implementation detail. However, it should help to understand the
6111 inner workings of U-Boot and make it easier to port it to custom
6115 Initial Stack, Global Data:
6116 ---------------------------
6118 The implementation of U-Boot is complicated by the fact that U-Boot
6119 starts running out of ROM (flash memory), usually without access to
6120 system RAM (because the memory controller is not initialized yet).
6121 This means that we don't have writable Data or BSS segments, and BSS
6122 is not initialized as zero. To be able to get a C environment working
6123 at all, we have to allocate at least a minimal stack. Implementation
6124 options for this are defined and restricted by the CPU used: Some CPU
6125 models provide on-chip memory (like the IMMR area on MPC8xx and
6126 MPC826x processors), on others (parts of) the data cache can be
6127 locked as (mis-) used as memory, etc.
6129 Chris Hallinan posted a good summary of these issues to the
6130 U-Boot mailing list:
6132 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
6133 From: "Chris Hallinan" <clh@net1plus.com>
6134 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
6137 Correct me if I'm wrong, folks, but the way I understand it
6138 is this: Using DCACHE as initial RAM for Stack, etc, does not
6139 require any physical RAM backing up the cache. The cleverness
6140 is that the cache is being used as a temporary supply of
6141 necessary storage before the SDRAM controller is setup. It's
6142 beyond the scope of this list to explain the details, but you
6143 can see how this works by studying the cache architecture and
6144 operation in the architecture and processor-specific manuals.
6146 OCM is On Chip Memory, which I believe the 405GP has 4K. It
6147 is another option for the system designer to use as an
6148 initial stack/RAM area prior to SDRAM being available. Either
6149 option should work for you. Using CS 4 should be fine if your
6150 board designers haven't used it for something that would
6151 cause you grief during the initial boot! It is frequently not
6154 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
6155 with your processor/board/system design. The default value
6156 you will find in any recent u-boot distribution in
6157 walnut.h should work for you. I'd set it to a value larger
6158 than your SDRAM module. If you have a 64MB SDRAM module, set
6159 it above 400_0000. Just make sure your board has no resources
6160 that are supposed to respond to that address! That code in
6161 start.S has been around a while and should work as is when
6162 you get the config right.
6167 It is essential to remember this, since it has some impact on the C
6168 code for the initialization procedures:
6170 * Initialized global data (data segment) is read-only. Do not attempt
6173 * Do not use any uninitialized global data (or implicitely initialized
6174 as zero data - BSS segment) at all - this is undefined, initiali-
6175 zation is performed later (when relocating to RAM).
6177 * Stack space is very limited. Avoid big data buffers or things like
6180 Having only the stack as writable memory limits means we cannot use
6181 normal global data to share information beween the code. But it
6182 turned out that the implementation of U-Boot can be greatly
6183 simplified by making a global data structure (gd_t) available to all
6184 functions. We could pass a pointer to this data as argument to _all_
6185 functions, but this would bloat the code. Instead we use a feature of
6186 the GCC compiler (Global Register Variables) to share the data: we
6187 place a pointer (gd) to the global data into a register which we
6188 reserve for this purpose.
6190 When choosing a register for such a purpose we are restricted by the
6191 relevant (E)ABI specifications for the current architecture, and by
6192 GCC's implementation.
6194 For PowerPC, the following registers have specific use:
6196 R2: reserved for system use
6197 R3-R4: parameter passing and return values
6198 R5-R10: parameter passing
6199 R13: small data area pointer
6203 (U-Boot also uses R12 as internal GOT pointer. r12
6204 is a volatile register so r12 needs to be reset when
6205 going back and forth between asm and C)
6207 ==> U-Boot will use R2 to hold a pointer to the global data
6209 Note: on PPC, we could use a static initializer (since the
6210 address of the global data structure is known at compile time),
6211 but it turned out that reserving a register results in somewhat
6212 smaller code - although the code savings are not that big (on
6213 average for all boards 752 bytes for the whole U-Boot image,
6214 624 text + 127 data).
6216 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
6217 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
6219 ==> U-Boot will use P3 to hold a pointer to the global data
6221 On ARM, the following registers are used:
6223 R0: function argument word/integer result
6224 R1-R3: function argument word
6225 R9: platform specific
6226 R10: stack limit (used only if stack checking is enabled)
6227 R11: argument (frame) pointer
6228 R12: temporary workspace
6231 R15: program counter
6233 ==> U-Boot will use R9 to hold a pointer to the global data
6235 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
6237 On Nios II, the ABI is documented here:
6238 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
6240 ==> U-Boot will use gp to hold a pointer to the global data
6242 Note: on Nios II, we give "-G0" option to gcc and don't use gp
6243 to access small data sections, so gp is free.
6245 On NDS32, the following registers are used:
6247 R0-R1: argument/return
6249 R15: temporary register for assembler
6250 R16: trampoline register
6251 R28: frame pointer (FP)
6252 R29: global pointer (GP)
6253 R30: link register (LP)
6254 R31: stack pointer (SP)
6255 PC: program counter (PC)
6257 ==> U-Boot will use R10 to hold a pointer to the global data
6259 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
6260 or current versions of GCC may "optimize" the code too much.
6265 U-Boot runs in system state and uses physical addresses, i.e. the
6266 MMU is not used either for address mapping nor for memory protection.
6268 The available memory is mapped to fixed addresses using the memory
6269 controller. In this process, a contiguous block is formed for each
6270 memory type (Flash, SDRAM, SRAM), even when it consists of several
6271 physical memory banks.
6273 U-Boot is installed in the first 128 kB of the first Flash bank (on
6274 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
6275 booting and sizing and initializing DRAM, the code relocates itself
6276 to the upper end of DRAM. Immediately below the U-Boot code some
6277 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
6278 configuration setting]. Below that, a structure with global Board
6279 Info data is placed, followed by the stack (growing downward).
6281 Additionally, some exception handler code is copied to the low 8 kB
6282 of DRAM (0x00000000 ... 0x00001FFF).
6284 So a typical memory configuration with 16 MB of DRAM could look like
6287 0x0000 0000 Exception Vector code
6290 0x0000 2000 Free for Application Use
6296 0x00FB FF20 Monitor Stack (Growing downward)
6297 0x00FB FFAC Board Info Data and permanent copy of global data
6298 0x00FC 0000 Malloc Arena
6301 0x00FE 0000 RAM Copy of Monitor Code
6302 ... eventually: LCD or video framebuffer
6303 ... eventually: pRAM (Protected RAM - unchanged by reset)
6304 0x00FF FFFF [End of RAM]
6307 System Initialization:
6308 ----------------------
6310 In the reset configuration, U-Boot starts at the reset entry point
6311 (on most PowerPC systems at address 0x00000100). Because of the reset
6312 configuration for CS0# this is a mirror of the onboard Flash memory.
6313 To be able to re-map memory U-Boot then jumps to its link address.
6314 To be able to implement the initialization code in C, a (small!)
6315 initial stack is set up in the internal Dual Ported RAM (in case CPUs
6316 which provide such a feature like MPC8xx or MPC8260), or in a locked
6317 part of the data cache. After that, U-Boot initializes the CPU core,
6318 the caches and the SIU.
6320 Next, all (potentially) available memory banks are mapped using a
6321 preliminary mapping. For example, we put them on 512 MB boundaries
6322 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
6323 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
6324 programmed for SDRAM access. Using the temporary configuration, a
6325 simple memory test is run that determines the size of the SDRAM
6328 When there is more than one SDRAM bank, and the banks are of
6329 different size, the largest is mapped first. For equal size, the first
6330 bank (CS2#) is mapped first. The first mapping is always for address
6331 0x00000000, with any additional banks following immediately to create
6332 contiguous memory starting from 0.
6334 Then, the monitor installs itself at the upper end of the SDRAM area
6335 and allocates memory for use by malloc() and for the global Board
6336 Info data; also, the exception vector code is copied to the low RAM
6337 pages, and the final stack is set up.
6339 Only after this relocation will you have a "normal" C environment;
6340 until that you are restricted in several ways, mostly because you are
6341 running from ROM, and because the code will have to be relocated to a
6345 U-Boot Porting Guide:
6346 ----------------------
6348 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
6352 int main(int argc, char *argv[])
6354 sighandler_t no_more_time;
6356 signal(SIGALRM, no_more_time);
6357 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
6359 if (available_money > available_manpower) {
6360 Pay consultant to port U-Boot;
6364 Download latest U-Boot source;
6366 Subscribe to u-boot mailing list;
6369 email("Hi, I am new to U-Boot, how do I get started?");
6372 Read the README file in the top level directory;
6373 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6374 Read applicable doc/*.README;
6375 Read the source, Luke;
6376 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6379 if (available_money > toLocalCurrency ($2500))
6382 Add a lot of aggravation and time;
6384 if (a similar board exists) { /* hopefully... */
6385 cp -a board/<similar> board/<myboard>
6386 cp include/configs/<similar>.h include/configs/<myboard>.h
6388 Create your own board support subdirectory;
6389 Create your own board include/configs/<myboard>.h file;
6391 Edit new board/<myboard> files
6392 Edit new include/configs/<myboard>.h
6397 Add / modify source code;
6401 email("Hi, I am having problems...");
6403 Send patch file to the U-Boot email list;
6404 if (reasonable critiques)
6405 Incorporate improvements from email list code review;
6407 Defend code as written;
6413 void no_more_time (int sig)
6422 All contributions to U-Boot should conform to the Linux kernel
6423 coding style; see the file "Documentation/CodingStyle" and the script
6424 "scripts/Lindent" in your Linux kernel source directory.
6426 Source files originating from a different project (for example the
6427 MTD subsystem) are generally exempt from these guidelines and are not
6428 reformated to ease subsequent migration to newer versions of those
6431 Please note that U-Boot is implemented in C (and to some small parts in
6432 Assembler); no C++ is used, so please do not use C++ style comments (//)
6435 Please also stick to the following formatting rules:
6436 - remove any trailing white space
6437 - use TAB characters for indentation and vertical alignment, not spaces
6438 - make sure NOT to use DOS '\r\n' line feeds
6439 - do not add more than 2 consecutive empty lines to source files
6440 - do not add trailing empty lines to source files
6442 Submissions which do not conform to the standards may be returned
6443 with a request to reformat the changes.
6449 Since the number of patches for U-Boot is growing, we need to
6450 establish some rules. Submissions which do not conform to these rules
6451 may be rejected, even when they contain important and valuable stuff.
6453 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6455 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
6456 see http://lists.denx.de/mailman/listinfo/u-boot
6458 When you send a patch, please include the following information with
6461 * For bug fixes: a description of the bug and how your patch fixes
6462 this bug. Please try to include a way of demonstrating that the
6463 patch actually fixes something.
6465 * For new features: a description of the feature and your
6468 * A CHANGELOG entry as plaintext (separate from the patch)
6470 * For major contributions, your entry to the CREDITS file
6472 * When you add support for a new board, don't forget to add a
6473 maintainer e-mail address to the boards.cfg file, too.
6475 * If your patch adds new configuration options, don't forget to
6476 document these in the README file.
6478 * The patch itself. If you are using git (which is *strongly*
6479 recommended) you can easily generate the patch using the
6480 "git format-patch". If you then use "git send-email" to send it to
6481 the U-Boot mailing list, you will avoid most of the common problems
6482 with some other mail clients.
6484 If you cannot use git, use "diff -purN OLD NEW". If your version of
6485 diff does not support these options, then get the latest version of
6488 The current directory when running this command shall be the parent
6489 directory of the U-Boot source tree (i. e. please make sure that
6490 your patch includes sufficient directory information for the
6493 We prefer patches as plain text. MIME attachments are discouraged,
6494 and compressed attachments must not be used.
6496 * If one logical set of modifications affects or creates several
6497 files, all these changes shall be submitted in a SINGLE patch file.
6499 * Changesets that contain different, unrelated modifications shall be
6500 submitted as SEPARATE patches, one patch per changeset.
6505 * Before sending the patch, run the MAKEALL script on your patched
6506 source tree and make sure that no errors or warnings are reported
6507 for any of the boards.
6509 * Keep your modifications to the necessary minimum: A patch
6510 containing several unrelated changes or arbitrary reformats will be
6511 returned with a request to re-formatting / split it.
6513 * If you modify existing code, make sure that your new code does not
6514 add to the memory footprint of the code ;-) Small is beautiful!
6515 When adding new features, these should compile conditionally only
6516 (using #ifdef), and the resulting code with the new feature
6517 disabled must not need more memory than the old code without your
6520 * Remember that there is a size limit of 100 kB per message on the
6521 u-boot mailing list. Bigger patches will be moderated. If they are
6522 reasonable and not too big, they will be acknowledged. But patches
6523 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob