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/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 - Journaling Flash filesystem support:
1633 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1634 CONFIG_JFFS2_NAND_DEV
1635 Define these for a default partition on a NAND device
1637 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1638 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1639 Define these for a default partition on a NOR device
1641 CONFIG_SYS_JFFS_CUSTOM_PART
1642 Define this to create an own partition. You have to provide a
1643 function struct part_info* jffs2_part_info(int part_num)
1645 If you define only one JFFS2 partition you may also want to
1646 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1647 to disable the command chpart. This is the default when you
1648 have not defined a custom partition
1650 - FAT(File Allocation Table) filesystem write function support:
1653 Define this to enable support for saving memory data as a
1654 file in FAT formatted partition.
1656 This will also enable the command "fatwrite" enabling the
1657 user to write files to FAT.
1659 CBFS (Coreboot Filesystem) support
1662 Define this to enable support for reading from a Coreboot
1663 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1666 - FAT(File Allocation Table) filesystem cluster size:
1667 CONFIG_FS_FAT_MAX_CLUSTSIZE
1669 Define the max cluster size for fat operations else
1670 a default value of 65536 will be defined.
1675 Define this to enable standard (PC-Style) keyboard
1679 Standard PC keyboard driver with US (is default) and
1680 GERMAN key layout (switch via environment 'keymap=de') support.
1681 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1682 for cfb_console. Supports cursor blinking.
1685 Enables a Chrome OS keyboard using the CROS_EC interface.
1686 This uses CROS_EC to communicate with a second microcontroller
1687 which provides key scans on request.
1692 Define this to enable video support (for output to
1695 CONFIG_VIDEO_CT69000
1697 Enable Chips & Technologies 69000 Video chip
1699 CONFIG_VIDEO_SMI_LYNXEM
1700 Enable Silicon Motion SMI 712/710/810 Video chip. The
1701 video output is selected via environment 'videoout'
1702 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1705 For the CT69000 and SMI_LYNXEM drivers, videomode is
1706 selected via environment 'videomode'. Two different ways
1708 - "videomode=num" 'num' is a standard LiLo mode numbers.
1709 Following standard modes are supported (* is default):
1711 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1712 -------------+---------------------------------------------
1713 8 bits | 0x301* 0x303 0x305 0x161 0x307
1714 15 bits | 0x310 0x313 0x316 0x162 0x319
1715 16 bits | 0x311 0x314 0x317 0x163 0x31A
1716 24 bits | 0x312 0x315 0x318 ? 0x31B
1717 -------------+---------------------------------------------
1718 (i.e. setenv videomode 317; saveenv; reset;)
1720 - "videomode=bootargs" all the video parameters are parsed
1721 from the bootargs. (See drivers/video/videomodes.c)
1724 CONFIG_VIDEO_SED13806
1725 Enable Epson SED13806 driver. This driver supports 8bpp
1726 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1727 or CONFIG_VIDEO_SED13806_16BPP
1730 Enable the Freescale DIU video driver. Reference boards for
1731 SOCs that have a DIU should define this macro to enable DIU
1732 support, and should also define these other macros:
1738 CONFIG_VIDEO_SW_CURSOR
1739 CONFIG_VGA_AS_SINGLE_DEVICE
1741 CONFIG_VIDEO_BMP_LOGO
1743 The DIU driver will look for the 'video-mode' environment
1744 variable, and if defined, enable the DIU as a console during
1745 boot. See the documentation file README.video for a
1746 description of this variable.
1750 Enable the VGA video / BIOS for x86. The alternative if you
1751 are using coreboot is to use the coreboot frame buffer
1758 Define this to enable a custom keyboard support.
1759 This simply calls drv_keyboard_init() which must be
1760 defined in your board-specific files.
1761 The only board using this so far is RBC823.
1763 - LCD Support: CONFIG_LCD
1765 Define this to enable LCD support (for output to LCD
1766 display); also select one of the supported displays
1767 by defining one of these:
1771 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1773 CONFIG_NEC_NL6448AC33:
1775 NEC NL6448AC33-18. Active, color, single scan.
1777 CONFIG_NEC_NL6448BC20
1779 NEC NL6448BC20-08. 6.5", 640x480.
1780 Active, color, single scan.
1782 CONFIG_NEC_NL6448BC33_54
1784 NEC NL6448BC33-54. 10.4", 640x480.
1785 Active, color, single scan.
1789 Sharp 320x240. Active, color, single scan.
1790 It isn't 16x9, and I am not sure what it is.
1792 CONFIG_SHARP_LQ64D341
1794 Sharp LQ64D341 display, 640x480.
1795 Active, color, single scan.
1799 HLD1045 display, 640x480.
1800 Active, color, single scan.
1804 Optrex CBL50840-2 NF-FW 99 22 M5
1806 Hitachi LMG6912RPFC-00T
1810 320x240. Black & white.
1812 Normally display is black on white background; define
1813 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1815 CONFIG_LCD_ALIGNMENT
1817 Normally the LCD is page-aligned (tyically 4KB). If this is
1818 defined then the LCD will be aligned to this value instead.
1819 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1820 here, since it is cheaper to change data cache settings on
1821 a per-section basis.
1823 CONFIG_CONSOLE_SCROLL_LINES
1825 When the console need to be scrolled, this is the number of
1826 lines to scroll by. It defaults to 1. Increasing this makes
1827 the console jump but can help speed up operation when scrolling
1832 Support drawing of RLE8-compressed bitmaps on the LCD.
1836 Enables an 'i2c edid' command which can read EDID
1837 information over I2C from an attached LCD display.
1839 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1841 If this option is set, the environment is checked for
1842 a variable "splashimage". If found, the usual display
1843 of logo, copyright and system information on the LCD
1844 is suppressed and the BMP image at the address
1845 specified in "splashimage" is loaded instead. The
1846 console is redirected to the "nulldev", too. This
1847 allows for a "silent" boot where a splash screen is
1848 loaded very quickly after power-on.
1850 CONFIG_SPLASHIMAGE_GUARD
1852 If this option is set, then U-Boot will prevent the environment
1853 variable "splashimage" from being set to a problematic address
1854 (see README.displaying-bmps).
1855 This option is useful for targets where, due to alignment
1856 restrictions, an improperly aligned BMP image will cause a data
1857 abort. If you think you will not have problems with unaligned
1858 accesses (for example because your toolchain prevents them)
1859 there is no need to set this option.
1861 CONFIG_SPLASH_SCREEN_ALIGN
1863 If this option is set the splash image can be freely positioned
1864 on the screen. Environment variable "splashpos" specifies the
1865 position as "x,y". If a positive number is given it is used as
1866 number of pixel from left/top. If a negative number is given it
1867 is used as number of pixel from right/bottom. You can also
1868 specify 'm' for centering the image.
1871 setenv splashpos m,m
1872 => image at center of screen
1874 setenv splashpos 30,20
1875 => image at x = 30 and y = 20
1877 setenv splashpos -10,m
1878 => vertically centered image
1879 at x = dspWidth - bmpWidth - 9
1881 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1883 If this option is set, additionally to standard BMP
1884 images, gzipped BMP images can be displayed via the
1885 splashscreen support or the bmp command.
1887 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1889 If this option is set, 8-bit RLE compressed BMP images
1890 can be displayed via the splashscreen support or the
1893 - Do compresssing for memory range:
1896 If this option is set, it would use zlib deflate method
1897 to compress the specified memory at its best effort.
1899 - Compression support:
1902 Enabled by default to support gzip compressed images.
1906 If this option is set, support for bzip2 compressed
1907 images is included. If not, only uncompressed and gzip
1908 compressed images are supported.
1910 NOTE: the bzip2 algorithm requires a lot of RAM, so
1911 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1916 If this option is set, support for lzma compressed
1919 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1920 requires an amount of dynamic memory that is given by the
1923 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1925 Where lc and lp stand for, respectively, Literal context bits
1926 and Literal pos bits.
1928 This value is upper-bounded by 14MB in the worst case. Anyway,
1929 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1930 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1931 a very small buffer.
1933 Use the lzmainfo tool to determinate the lc and lp values and
1934 then calculate the amount of needed dynamic memory (ensuring
1935 the appropriate CONFIG_SYS_MALLOC_LEN value).
1939 If this option is set, support for LZO compressed images
1945 The address of PHY on MII bus.
1947 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1949 The clock frequency of the MII bus
1953 If this option is set, support for speed/duplex
1954 detection of gigabit PHY is included.
1956 CONFIG_PHY_RESET_DELAY
1958 Some PHY like Intel LXT971A need extra delay after
1959 reset before any MII register access is possible.
1960 For such PHY, set this option to the usec delay
1961 required. (minimum 300usec for LXT971A)
1963 CONFIG_PHY_CMD_DELAY (ppc4xx)
1965 Some PHY like Intel LXT971A need extra delay after
1966 command issued before MII status register can be read
1976 Define a default value for Ethernet address to use
1977 for the respective Ethernet interface, in case this
1978 is not determined automatically.
1983 Define a default value for the IP address to use for
1984 the default Ethernet interface, in case this is not
1985 determined through e.g. bootp.
1986 (Environment variable "ipaddr")
1988 - Server IP address:
1991 Defines a default value for the IP address of a TFTP
1992 server to contact when using the "tftboot" command.
1993 (Environment variable "serverip")
1995 CONFIG_KEEP_SERVERADDR
1997 Keeps the server's MAC address, in the env 'serveraddr'
1998 for passing to bootargs (like Linux's netconsole option)
2000 - Gateway IP address:
2003 Defines a default value for the IP address of the
2004 default router where packets to other networks are
2006 (Environment variable "gatewayip")
2011 Defines a default value for the subnet mask (or
2012 routing prefix) which is used to determine if an IP
2013 address belongs to the local subnet or needs to be
2014 forwarded through a router.
2015 (Environment variable "netmask")
2017 - Multicast TFTP Mode:
2020 Defines whether you want to support multicast TFTP as per
2021 rfc-2090; for example to work with atftp. Lets lots of targets
2022 tftp down the same boot image concurrently. Note: the Ethernet
2023 driver in use must provide a function: mcast() to join/leave a
2026 - BOOTP Recovery Mode:
2027 CONFIG_BOOTP_RANDOM_DELAY
2029 If you have many targets in a network that try to
2030 boot using BOOTP, you may want to avoid that all
2031 systems send out BOOTP requests at precisely the same
2032 moment (which would happen for instance at recovery
2033 from a power failure, when all systems will try to
2034 boot, thus flooding the BOOTP server. Defining
2035 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
2036 inserted before sending out BOOTP requests. The
2037 following delays are inserted then:
2039 1st BOOTP request: delay 0 ... 1 sec
2040 2nd BOOTP request: delay 0 ... 2 sec
2041 3rd BOOTP request: delay 0 ... 4 sec
2043 BOOTP requests: delay 0 ... 8 sec
2045 CONFIG_BOOTP_ID_CACHE_SIZE
2047 BOOTP packets are uniquely identified using a 32-bit ID. The
2048 server will copy the ID from client requests to responses and
2049 U-Boot will use this to determine if it is the destination of
2050 an incoming response. Some servers will check that addresses
2051 aren't in use before handing them out (usually using an ARP
2052 ping) and therefore take up to a few hundred milliseconds to
2053 respond. Network congestion may also influence the time it
2054 takes for a response to make it back to the client. If that
2055 time is too long, U-Boot will retransmit requests. In order
2056 to allow earlier responses to still be accepted after these
2057 retransmissions, U-Boot's BOOTP client keeps a small cache of
2058 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
2059 cache. The default is to keep IDs for up to four outstanding
2060 requests. Increasing this will allow U-Boot to accept offers
2061 from a BOOTP client in networks with unusually high latency.
2063 - DHCP Advanced Options:
2064 You can fine tune the DHCP functionality by defining
2065 CONFIG_BOOTP_* symbols:
2067 CONFIG_BOOTP_SUBNETMASK
2068 CONFIG_BOOTP_GATEWAY
2069 CONFIG_BOOTP_HOSTNAME
2070 CONFIG_BOOTP_NISDOMAIN
2071 CONFIG_BOOTP_BOOTPATH
2072 CONFIG_BOOTP_BOOTFILESIZE
2075 CONFIG_BOOTP_SEND_HOSTNAME
2076 CONFIG_BOOTP_NTPSERVER
2077 CONFIG_BOOTP_TIMEOFFSET
2078 CONFIG_BOOTP_VENDOREX
2079 CONFIG_BOOTP_MAY_FAIL
2081 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
2082 environment variable, not the BOOTP server.
2084 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
2085 after the configured retry count, the call will fail
2086 instead of starting over. This can be used to fail over
2087 to Link-local IP address configuration if the DHCP server
2090 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
2091 serverip from a DHCP server, it is possible that more
2092 than one DNS serverip is offered to the client.
2093 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
2094 serverip will be stored in the additional environment
2095 variable "dnsip2". The first DNS serverip is always
2096 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
2099 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
2100 to do a dynamic update of a DNS server. To do this, they
2101 need the hostname of the DHCP requester.
2102 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
2103 of the "hostname" environment variable is passed as
2104 option 12 to the DHCP server.
2106 CONFIG_BOOTP_DHCP_REQUEST_DELAY
2108 A 32bit value in microseconds for a delay between
2109 receiving a "DHCP Offer" and sending the "DHCP Request".
2110 This fixes a problem with certain DHCP servers that don't
2111 respond 100% of the time to a "DHCP request". E.g. On an
2112 AT91RM9200 processor running at 180MHz, this delay needed
2113 to be *at least* 15,000 usec before a Windows Server 2003
2114 DHCP server would reply 100% of the time. I recommend at
2115 least 50,000 usec to be safe. The alternative is to hope
2116 that one of the retries will be successful but note that
2117 the DHCP timeout and retry process takes a longer than
2120 - Link-local IP address negotiation:
2121 Negotiate with other link-local clients on the local network
2122 for an address that doesn't require explicit configuration.
2123 This is especially useful if a DHCP server cannot be guaranteed
2124 to exist in all environments that the device must operate.
2126 See doc/README.link-local for more information.
2129 CONFIG_CDP_DEVICE_ID
2131 The device id used in CDP trigger frames.
2133 CONFIG_CDP_DEVICE_ID_PREFIX
2135 A two character string which is prefixed to the MAC address
2140 A printf format string which contains the ascii name of
2141 the port. Normally is set to "eth%d" which sets
2142 eth0 for the first Ethernet, eth1 for the second etc.
2144 CONFIG_CDP_CAPABILITIES
2146 A 32bit integer which indicates the device capabilities;
2147 0x00000010 for a normal host which does not forwards.
2151 An ascii string containing the version of the software.
2155 An ascii string containing the name of the platform.
2159 A 32bit integer sent on the trigger.
2161 CONFIG_CDP_POWER_CONSUMPTION
2163 A 16bit integer containing the power consumption of the
2164 device in .1 of milliwatts.
2166 CONFIG_CDP_APPLIANCE_VLAN_TYPE
2168 A byte containing the id of the VLAN.
2170 - Status LED: CONFIG_STATUS_LED
2172 Several configurations allow to display the current
2173 status using a LED. For instance, the LED will blink
2174 fast while running U-Boot code, stop blinking as
2175 soon as a reply to a BOOTP request was received, and
2176 start blinking slow once the Linux kernel is running
2177 (supported by a status LED driver in the Linux
2178 kernel). Defining CONFIG_STATUS_LED enables this
2184 The status LED can be connected to a GPIO pin.
2185 In such cases, the gpio_led driver can be used as a
2186 status LED backend implementation. Define CONFIG_GPIO_LED
2187 to include the gpio_led driver in the U-Boot binary.
2189 CONFIG_GPIO_LED_INVERTED_TABLE
2190 Some GPIO connected LEDs may have inverted polarity in which
2191 case the GPIO high value corresponds to LED off state and
2192 GPIO low value corresponds to LED on state.
2193 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
2194 with a list of GPIO LEDs that have inverted polarity.
2196 - CAN Support: CONFIG_CAN_DRIVER
2198 Defining CONFIG_CAN_DRIVER enables CAN driver support
2199 on those systems that support this (optional)
2200 feature, like the TQM8xxL modules.
2202 - I2C Support: CONFIG_SYS_I2C
2204 This enable the NEW i2c subsystem, and will allow you to use
2205 i2c commands at the u-boot command line (as long as you set
2206 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
2207 based realtime clock chips or other i2c devices. See
2208 common/cmd_i2c.c for a description of the command line
2211 ported i2c driver to the new framework:
2212 - drivers/i2c/soft_i2c.c:
2213 - activate first bus with CONFIG_SYS_I2C_SOFT define
2214 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
2215 for defining speed and slave address
2216 - activate second bus with I2C_SOFT_DECLARATIONS2 define
2217 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
2218 for defining speed and slave address
2219 - activate third bus with I2C_SOFT_DECLARATIONS3 define
2220 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
2221 for defining speed and slave address
2222 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
2223 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
2224 for defining speed and slave address
2226 - drivers/i2c/fsl_i2c.c:
2227 - activate i2c driver with CONFIG_SYS_I2C_FSL
2228 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
2229 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
2230 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
2232 - If your board supports a second fsl i2c bus, define
2233 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
2234 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
2235 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
2238 - drivers/i2c/tegra_i2c.c:
2239 - activate this driver with CONFIG_SYS_I2C_TEGRA
2240 - This driver adds 4 i2c buses with a fix speed from
2241 100000 and the slave addr 0!
2243 - drivers/i2c/ppc4xx_i2c.c
2244 - activate this driver with CONFIG_SYS_I2C_PPC4XX
2245 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
2246 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
2248 - drivers/i2c/i2c_mxc.c
2249 - activate this driver with CONFIG_SYS_I2C_MXC
2250 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
2251 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
2252 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
2253 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
2254 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
2255 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
2256 If thoses defines are not set, default value is 100000
2257 for speed, and 0 for slave.
2259 - drivers/i2c/rcar_i2c.c:
2260 - activate this driver with CONFIG_SYS_I2C_RCAR
2261 - This driver adds 4 i2c buses
2263 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
2264 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
2265 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
2266 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
2267 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
2268 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
2269 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
2270 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
2271 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
2273 - drivers/i2c/sh_i2c.c:
2274 - activate this driver with CONFIG_SYS_I2C_SH
2275 - This driver adds from 2 to 5 i2c buses
2277 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
2278 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
2279 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
2280 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
2281 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
2282 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
2283 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
2284 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
2285 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
2286 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
2287 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5
2288 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5
2289 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses
2291 - drivers/i2c/omap24xx_i2c.c
2292 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
2293 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
2294 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
2295 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
2296 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
2297 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
2298 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
2299 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
2300 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
2301 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
2302 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
2304 - drivers/i2c/zynq_i2c.c
2305 - activate this driver with CONFIG_SYS_I2C_ZYNQ
2306 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
2307 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
2309 - drivers/i2c/s3c24x0_i2c.c:
2310 - activate this driver with CONFIG_SYS_I2C_S3C24X0
2311 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
2312 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
2313 with a fix speed from 100000 and the slave addr 0!
2315 - drivers/i2c/ihs_i2c.c
2316 - activate this driver with CONFIG_SYS_I2C_IHS
2317 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
2318 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
2319 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
2320 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
2321 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
2322 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
2323 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
2324 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
2325 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
2326 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
2327 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
2328 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
2332 CONFIG_SYS_NUM_I2C_BUSES
2333 Hold the number of i2c busses you want to use. If you
2334 don't use/have i2c muxes on your i2c bus, this
2335 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2338 CONFIG_SYS_I2C_DIRECT_BUS
2339 define this, if you don't use i2c muxes on your hardware.
2340 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2343 CONFIG_SYS_I2C_MAX_HOPS
2344 define how many muxes are maximal consecutively connected
2345 on one i2c bus. If you not use i2c muxes, omit this
2348 CONFIG_SYS_I2C_BUSES
2349 hold a list of busses you want to use, only used if
2350 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2351 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2352 CONFIG_SYS_NUM_I2C_BUSES = 9:
2354 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2355 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2356 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2357 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2358 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2359 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2360 {1, {I2C_NULL_HOP}}, \
2361 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2362 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2366 bus 0 on adapter 0 without a mux
2367 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2368 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2369 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2370 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2371 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2372 bus 6 on adapter 1 without a mux
2373 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2374 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2376 If you do not have i2c muxes on your board, omit this define.
2378 - Legacy I2C Support: CONFIG_HARD_I2C
2380 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2381 provides the following compelling advantages:
2383 - more than one i2c adapter is usable
2384 - approved multibus support
2385 - better i2c mux support
2387 ** Please consider updating your I2C driver now. **
2389 These enable legacy I2C serial bus commands. Defining
2390 CONFIG_HARD_I2C will include the appropriate I2C driver
2391 for the selected CPU.
2393 This will allow you to use i2c commands at the u-boot
2394 command line (as long as you set CONFIG_CMD_I2C in
2395 CONFIG_COMMANDS) and communicate with i2c based realtime
2396 clock chips. See common/cmd_i2c.c for a description of the
2397 command line interface.
2399 CONFIG_HARD_I2C selects a hardware I2C controller.
2401 There are several other quantities that must also be
2402 defined when you define CONFIG_HARD_I2C.
2404 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2405 to be the frequency (in Hz) at which you wish your i2c bus
2406 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2407 the CPU's i2c node address).
2409 Now, the u-boot i2c code for the mpc8xx
2410 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2411 and so its address should therefore be cleared to 0 (See,
2412 eg, MPC823e User's Manual p.16-473). So, set
2413 CONFIG_SYS_I2C_SLAVE to 0.
2415 CONFIG_SYS_I2C_INIT_MPC5XXX
2417 When a board is reset during an i2c bus transfer
2418 chips might think that the current transfer is still
2419 in progress. Reset the slave devices by sending start
2420 commands until the slave device responds.
2422 That's all that's required for CONFIG_HARD_I2C.
2424 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2425 then the following macros need to be defined (examples are
2426 from include/configs/lwmon.h):
2430 (Optional). Any commands necessary to enable the I2C
2431 controller or configure ports.
2433 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2437 (Only for MPC8260 CPU). The I/O port to use (the code
2438 assumes both bits are on the same port). Valid values
2439 are 0..3 for ports A..D.
2443 The code necessary to make the I2C data line active
2444 (driven). If the data line is open collector, this
2447 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2451 The code necessary to make the I2C data line tri-stated
2452 (inactive). If the data line is open collector, this
2455 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2459 Code that returns true if the I2C data line is high,
2462 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2466 If <bit> is true, sets the I2C data line high. If it
2467 is false, it clears it (low).
2469 eg: #define I2C_SDA(bit) \
2470 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2471 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2475 If <bit> is true, sets the I2C clock line high. If it
2476 is false, it clears it (low).
2478 eg: #define I2C_SCL(bit) \
2479 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2480 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2484 This delay is invoked four times per clock cycle so this
2485 controls the rate of data transfer. The data rate thus
2486 is 1 / (I2C_DELAY * 4). Often defined to be something
2489 #define I2C_DELAY udelay(2)
2491 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2493 If your arch supports the generic GPIO framework (asm/gpio.h),
2494 then you may alternatively define the two GPIOs that are to be
2495 used as SCL / SDA. Any of the previous I2C_xxx macros will
2496 have GPIO-based defaults assigned to them as appropriate.
2498 You should define these to the GPIO value as given directly to
2499 the generic GPIO functions.
2501 CONFIG_SYS_I2C_INIT_BOARD
2503 When a board is reset during an i2c bus transfer
2504 chips might think that the current transfer is still
2505 in progress. On some boards it is possible to access
2506 the i2c SCLK line directly, either by using the
2507 processor pin as a GPIO or by having a second pin
2508 connected to the bus. If this option is defined a
2509 custom i2c_init_board() routine in boards/xxx/board.c
2510 is run early in the boot sequence.
2512 CONFIG_SYS_I2C_BOARD_LATE_INIT
2514 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2515 defined a custom i2c_board_late_init() routine in
2516 boards/xxx/board.c is run AFTER the operations in i2c_init()
2517 is completed. This callpoint can be used to unreset i2c bus
2518 using CPU i2c controller register accesses for CPUs whose i2c
2519 controller provide such a method. It is called at the end of
2520 i2c_init() to allow i2c_init operations to setup the i2c bus
2521 controller on the CPU (e.g. setting bus speed & slave address).
2523 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2525 This option enables configuration of bi_iic_fast[] flags
2526 in u-boot bd_info structure based on u-boot environment
2527 variable "i2cfast". (see also i2cfast)
2529 CONFIG_I2C_MULTI_BUS
2531 This option allows the use of multiple I2C buses, each of which
2532 must have a controller. At any point in time, only one bus is
2533 active. To switch to a different bus, use the 'i2c dev' command.
2534 Note that bus numbering is zero-based.
2536 CONFIG_SYS_I2C_NOPROBES
2538 This option specifies a list of I2C devices that will be skipped
2539 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2540 is set, specify a list of bus-device pairs. Otherwise, specify
2541 a 1D array of device addresses
2544 #undef CONFIG_I2C_MULTI_BUS
2545 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2547 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2549 #define CONFIG_I2C_MULTI_BUS
2550 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2552 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2554 CONFIG_SYS_SPD_BUS_NUM
2556 If defined, then this indicates the I2C bus number for DDR SPD.
2557 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2559 CONFIG_SYS_RTC_BUS_NUM
2561 If defined, then this indicates the I2C bus number for the RTC.
2562 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2564 CONFIG_SYS_DTT_BUS_NUM
2566 If defined, then this indicates the I2C bus number for the DTT.
2567 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2569 CONFIG_SYS_I2C_DTT_ADDR:
2571 If defined, specifies the I2C address of the DTT device.
2572 If not defined, then U-Boot uses predefined value for
2573 specified DTT device.
2575 CONFIG_SOFT_I2C_READ_REPEATED_START
2577 defining this will force the i2c_read() function in
2578 the soft_i2c driver to perform an I2C repeated start
2579 between writing the address pointer and reading the
2580 data. If this define is omitted the default behaviour
2581 of doing a stop-start sequence will be used. Most I2C
2582 devices can use either method, but some require one or
2585 - SPI Support: CONFIG_SPI
2587 Enables SPI driver (so far only tested with
2588 SPI EEPROM, also an instance works with Crystal A/D and
2589 D/As on the SACSng board)
2593 Enables the driver for SPI controller on SuperH. Currently
2594 only SH7757 is supported.
2598 Enables extended (16-bit) SPI EEPROM addressing.
2599 (symmetrical to CONFIG_I2C_X)
2603 Enables a software (bit-bang) SPI driver rather than
2604 using hardware support. This is a general purpose
2605 driver that only requires three general I/O port pins
2606 (two outputs, one input) to function. If this is
2607 defined, the board configuration must define several
2608 SPI configuration items (port pins to use, etc). For
2609 an example, see include/configs/sacsng.h.
2613 Enables a hardware SPI driver for general-purpose reads
2614 and writes. As with CONFIG_SOFT_SPI, the board configuration
2615 must define a list of chip-select function pointers.
2616 Currently supported on some MPC8xxx processors. For an
2617 example, see include/configs/mpc8349emds.h.
2621 Enables the driver for the SPI controllers on i.MX and MXC
2622 SoCs. Currently i.MX31/35/51 are supported.
2624 CONFIG_SYS_SPI_MXC_WAIT
2625 Timeout for waiting until spi transfer completed.
2626 default: (CONFIG_SYS_HZ/100) /* 10 ms */
2628 - FPGA Support: CONFIG_FPGA
2630 Enables FPGA subsystem.
2632 CONFIG_FPGA_<vendor>
2634 Enables support for specific chip vendors.
2637 CONFIG_FPGA_<family>
2639 Enables support for FPGA family.
2640 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2644 Specify the number of FPGA devices to support.
2646 CONFIG_CMD_FPGA_LOADMK
2648 Enable support for fpga loadmk command
2650 CONFIG_CMD_FPGA_LOADP
2652 Enable support for fpga loadp command - load partial bitstream
2654 CONFIG_CMD_FPGA_LOADBP
2656 Enable support for fpga loadbp command - load partial bitstream
2659 CONFIG_SYS_FPGA_PROG_FEEDBACK
2661 Enable printing of hash marks during FPGA configuration.
2663 CONFIG_SYS_FPGA_CHECK_BUSY
2665 Enable checks on FPGA configuration interface busy
2666 status by the configuration function. This option
2667 will require a board or device specific function to
2672 If defined, a function that provides delays in the FPGA
2673 configuration driver.
2675 CONFIG_SYS_FPGA_CHECK_CTRLC
2676 Allow Control-C to interrupt FPGA configuration
2678 CONFIG_SYS_FPGA_CHECK_ERROR
2680 Check for configuration errors during FPGA bitfile
2681 loading. For example, abort during Virtex II
2682 configuration if the INIT_B line goes low (which
2683 indicated a CRC error).
2685 CONFIG_SYS_FPGA_WAIT_INIT
2687 Maximum time to wait for the INIT_B line to deassert
2688 after PROB_B has been deasserted during a Virtex II
2689 FPGA configuration sequence. The default time is 500
2692 CONFIG_SYS_FPGA_WAIT_BUSY
2694 Maximum time to wait for BUSY to deassert during
2695 Virtex II FPGA configuration. The default is 5 ms.
2697 CONFIG_SYS_FPGA_WAIT_CONFIG
2699 Time to wait after FPGA configuration. The default is
2702 - Configuration Management:
2705 If defined, this string will be added to the U-Boot
2706 version information (U_BOOT_VERSION)
2708 - Vendor Parameter Protection:
2710 U-Boot considers the values of the environment
2711 variables "serial#" (Board Serial Number) and
2712 "ethaddr" (Ethernet Address) to be parameters that
2713 are set once by the board vendor / manufacturer, and
2714 protects these variables from casual modification by
2715 the user. Once set, these variables are read-only,
2716 and write or delete attempts are rejected. You can
2717 change this behaviour:
2719 If CONFIG_ENV_OVERWRITE is #defined in your config
2720 file, the write protection for vendor parameters is
2721 completely disabled. Anybody can change or delete
2724 Alternatively, if you #define _both_ CONFIG_ETHADDR
2725 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2726 Ethernet address is installed in the environment,
2727 which can be changed exactly ONCE by the user. [The
2728 serial# is unaffected by this, i. e. it remains
2731 The same can be accomplished in a more flexible way
2732 for any variable by configuring the type of access
2733 to allow for those variables in the ".flags" variable
2734 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2739 Define this variable to enable the reservation of
2740 "protected RAM", i. e. RAM which is not overwritten
2741 by U-Boot. Define CONFIG_PRAM to hold the number of
2742 kB you want to reserve for pRAM. You can overwrite
2743 this default value by defining an environment
2744 variable "pram" to the number of kB you want to
2745 reserve. Note that the board info structure will
2746 still show the full amount of RAM. If pRAM is
2747 reserved, a new environment variable "mem" will
2748 automatically be defined to hold the amount of
2749 remaining RAM in a form that can be passed as boot
2750 argument to Linux, for instance like that:
2752 setenv bootargs ... mem=\${mem}
2755 This way you can tell Linux not to use this memory,
2756 either, which results in a memory region that will
2757 not be affected by reboots.
2759 *WARNING* If your board configuration uses automatic
2760 detection of the RAM size, you must make sure that
2761 this memory test is non-destructive. So far, the
2762 following board configurations are known to be
2765 IVMS8, IVML24, SPD8xx, TQM8xxL,
2766 HERMES, IP860, RPXlite, LWMON,
2769 - Access to physical memory region (> 4GB)
2770 Some basic support is provided for operations on memory not
2771 normally accessible to U-Boot - e.g. some architectures
2772 support access to more than 4GB of memory on 32-bit
2773 machines using physical address extension or similar.
2774 Define CONFIG_PHYSMEM to access this basic support, which
2775 currently only supports clearing the memory.
2780 Define this variable to stop the system in case of a
2781 fatal error, so that you have to reset it manually.
2782 This is probably NOT a good idea for an embedded
2783 system where you want the system to reboot
2784 automatically as fast as possible, but it may be
2785 useful during development since you can try to debug
2786 the conditions that lead to the situation.
2788 CONFIG_NET_RETRY_COUNT
2790 This variable defines the number of retries for
2791 network operations like ARP, RARP, TFTP, or BOOTP
2792 before giving up the operation. If not defined, a
2793 default value of 5 is used.
2797 Timeout waiting for an ARP reply in milliseconds.
2801 Timeout in milliseconds used in NFS protocol.
2802 If you encounter "ERROR: Cannot umount" in nfs command,
2803 try longer timeout such as
2804 #define CONFIG_NFS_TIMEOUT 10000UL
2806 - Command Interpreter:
2807 CONFIG_AUTO_COMPLETE
2809 Enable auto completion of commands using TAB.
2811 Note that this feature has NOT been implemented yet
2812 for the "hush" shell.
2815 CONFIG_SYS_HUSH_PARSER
2817 Define this variable to enable the "hush" shell (from
2818 Busybox) as command line interpreter, thus enabling
2819 powerful command line syntax like
2820 if...then...else...fi conditionals or `&&' and '||'
2821 constructs ("shell scripts").
2823 If undefined, you get the old, much simpler behaviour
2824 with a somewhat smaller memory footprint.
2827 CONFIG_SYS_PROMPT_HUSH_PS2
2829 This defines the secondary prompt string, which is
2830 printed when the command interpreter needs more input
2831 to complete a command. Usually "> ".
2835 In the current implementation, the local variables
2836 space and global environment variables space are
2837 separated. Local variables are those you define by
2838 simply typing `name=value'. To access a local
2839 variable later on, you have write `$name' or
2840 `${name}'; to execute the contents of a variable
2841 directly type `$name' at the command prompt.
2843 Global environment variables are those you use
2844 setenv/printenv to work with. To run a command stored
2845 in such a variable, you need to use the run command,
2846 and you must not use the '$' sign to access them.
2848 To store commands and special characters in a
2849 variable, please use double quotation marks
2850 surrounding the whole text of the variable, instead
2851 of the backslashes before semicolons and special
2854 - Commandline Editing and History:
2855 CONFIG_CMDLINE_EDITING
2857 Enable editing and History functions for interactive
2858 commandline input operations
2860 - Default Environment:
2861 CONFIG_EXTRA_ENV_SETTINGS
2863 Define this to contain any number of null terminated
2864 strings (variable = value pairs) that will be part of
2865 the default environment compiled into the boot image.
2867 For example, place something like this in your
2868 board's config file:
2870 #define CONFIG_EXTRA_ENV_SETTINGS \
2874 Warning: This method is based on knowledge about the
2875 internal format how the environment is stored by the
2876 U-Boot code. This is NOT an official, exported
2877 interface! Although it is unlikely that this format
2878 will change soon, there is no guarantee either.
2879 You better know what you are doing here.
2881 Note: overly (ab)use of the default environment is
2882 discouraged. Make sure to check other ways to preset
2883 the environment like the "source" command or the
2886 CONFIG_ENV_VARS_UBOOT_CONFIG
2888 Define this in order to add variables describing the
2889 U-Boot build configuration to the default environment.
2890 These will be named arch, cpu, board, vendor, and soc.
2892 Enabling this option will cause the following to be defined:
2900 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2902 Define this in order to add variables describing certain
2903 run-time determined information about the hardware to the
2904 environment. These will be named board_name, board_rev.
2906 CONFIG_DELAY_ENVIRONMENT
2908 Normally the environment is loaded when the board is
2909 intialised so that it is available to U-Boot. This inhibits
2910 that so that the environment is not available until
2911 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2912 this is instead controlled by the value of
2913 /config/load-environment.
2915 - DataFlash Support:
2916 CONFIG_HAS_DATAFLASH
2918 Defining this option enables DataFlash features and
2919 allows to read/write in Dataflash via the standard
2922 - Serial Flash support
2925 Defining this option enables SPI flash commands
2926 'sf probe/read/write/erase/update'.
2928 Usage requires an initial 'probe' to define the serial
2929 flash parameters, followed by read/write/erase/update
2932 The following defaults may be provided by the platform
2933 to handle the common case when only a single serial
2934 flash is present on the system.
2936 CONFIG_SF_DEFAULT_BUS Bus identifier
2937 CONFIG_SF_DEFAULT_CS Chip-select
2938 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2939 CONFIG_SF_DEFAULT_SPEED in Hz
2943 Define this option to include a destructive SPI flash
2946 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2948 Define this option to use the Bank addr/Extended addr
2949 support on SPI flashes which has size > 16Mbytes.
2951 CONFIG_SF_DUAL_FLASH Dual flash memories
2953 Define this option to use dual flash support where two flash
2954 memories can be connected with a given cs line.
2955 currently Xilinx Zynq qspi support these type of connections.
2957 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN
2958 enable the W#/Vpp signal to disable writing to the status
2959 register on ST MICRON flashes like the N25Q128.
2960 The status register write enable/disable bit, combined with
2961 the W#/VPP signal provides hardware data protection for the
2962 device as follows: When the enable/disable bit is set to 1,
2963 and the W#/VPP signal is driven LOW, the status register
2964 nonvolatile bits become read-only and the WRITE STATUS REGISTER
2965 operation will not execute. The only way to exit this
2966 hardware-protected mode is to drive W#/VPP HIGH.
2968 - SystemACE Support:
2971 Adding this option adds support for Xilinx SystemACE
2972 chips attached via some sort of local bus. The address
2973 of the chip must also be defined in the
2974 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2976 #define CONFIG_SYSTEMACE
2977 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2979 When SystemACE support is added, the "ace" device type
2980 becomes available to the fat commands, i.e. fatls.
2982 - TFTP Fixed UDP Port:
2985 If this is defined, the environment variable tftpsrcp
2986 is used to supply the TFTP UDP source port value.
2987 If tftpsrcp isn't defined, the normal pseudo-random port
2988 number generator is used.
2990 Also, the environment variable tftpdstp is used to supply
2991 the TFTP UDP destination port value. If tftpdstp isn't
2992 defined, the normal port 69 is used.
2994 The purpose for tftpsrcp is to allow a TFTP server to
2995 blindly start the TFTP transfer using the pre-configured
2996 target IP address and UDP port. This has the effect of
2997 "punching through" the (Windows XP) firewall, allowing
2998 the remainder of the TFTP transfer to proceed normally.
2999 A better solution is to properly configure the firewall,
3000 but sometimes that is not allowed.
3005 This enables a generic 'hash' command which can produce
3006 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
3010 Enable the hash verify command (hash -v). This adds to code
3013 CONFIG_SHA1 - support SHA1 hashing
3014 CONFIG_SHA256 - support SHA256 hashing
3016 Note: There is also a sha1sum command, which should perhaps
3017 be deprecated in favour of 'hash sha1'.
3019 - Freescale i.MX specific commands:
3020 CONFIG_CMD_HDMIDETECT
3021 This enables 'hdmidet' command which returns true if an
3022 HDMI monitor is detected. This command is i.MX 6 specific.
3025 This enables the 'bmode' (bootmode) command for forcing
3026 a boot from specific media.
3028 This is useful for forcing the ROM's usb downloader to
3029 activate upon a watchdog reset which is nice when iterating
3030 on U-Boot. Using the reset button or running bmode normal
3031 will set it back to normal. This command currently
3032 supports i.MX53 and i.MX6.
3037 This enables the RSA algorithm used for FIT image verification
3038 in U-Boot. See doc/uImage.FIT/signature.txt for more information.
3040 The signing part is build into mkimage regardless of this
3043 - bootcount support:
3044 CONFIG_BOOTCOUNT_LIMIT
3046 This enables the bootcounter support, see:
3047 http://www.denx.de/wiki/DULG/UBootBootCountLimit
3050 enable special bootcounter support on at91sam9xe based boards.
3052 enable special bootcounter support on blackfin based boards.
3054 enable special bootcounter support on da850 based boards.
3055 CONFIG_BOOTCOUNT_RAM
3056 enable support for the bootcounter in RAM
3057 CONFIG_BOOTCOUNT_I2C
3058 enable support for the bootcounter on an i2c (like RTC) device.
3059 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
3060 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
3062 CONFIG_BOOTCOUNT_ALEN = address len
3064 - Show boot progress:
3065 CONFIG_SHOW_BOOT_PROGRESS
3067 Defining this option allows to add some board-
3068 specific code (calling a user-provided function
3069 "show_boot_progress(int)") that enables you to show
3070 the system's boot progress on some display (for
3071 example, some LED's) on your board. At the moment,
3072 the following checkpoints are implemented:
3074 - Detailed boot stage timing
3076 Define this option to get detailed timing of each stage
3077 of the boot process.
3079 CONFIG_BOOTSTAGE_USER_COUNT
3080 This is the number of available user bootstage records.
3081 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
3082 a new ID will be allocated from this stash. If you exceed
3083 the limit, recording will stop.
3085 CONFIG_BOOTSTAGE_REPORT
3086 Define this to print a report before boot, similar to this:
3088 Timer summary in microseconds:
3091 3,575,678 3,575,678 board_init_f start
3092 3,575,695 17 arch_cpu_init A9
3093 3,575,777 82 arch_cpu_init done
3094 3,659,598 83,821 board_init_r start
3095 3,910,375 250,777 main_loop
3096 29,916,167 26,005,792 bootm_start
3097 30,361,327 445,160 start_kernel
3099 CONFIG_CMD_BOOTSTAGE
3100 Add a 'bootstage' command which supports printing a report
3101 and un/stashing of bootstage data.
3103 CONFIG_BOOTSTAGE_FDT
3104 Stash the bootstage information in the FDT. A root 'bootstage'
3105 node is created with each bootstage id as a child. Each child
3106 has a 'name' property and either 'mark' containing the
3107 mark time in microsecond, or 'accum' containing the
3108 accumulated time for that bootstage id in microseconds.
3113 name = "board_init_f";
3122 Code in the Linux kernel can find this in /proc/devicetree.
3124 Legacy uImage format:
3127 1 common/cmd_bootm.c before attempting to boot an image
3128 -1 common/cmd_bootm.c Image header has bad magic number
3129 2 common/cmd_bootm.c Image header has correct magic number
3130 -2 common/cmd_bootm.c Image header has bad checksum
3131 3 common/cmd_bootm.c Image header has correct checksum
3132 -3 common/cmd_bootm.c Image data has bad checksum
3133 4 common/cmd_bootm.c Image data has correct checksum
3134 -4 common/cmd_bootm.c Image is for unsupported architecture
3135 5 common/cmd_bootm.c Architecture check OK
3136 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
3137 6 common/cmd_bootm.c Image Type check OK
3138 -6 common/cmd_bootm.c gunzip uncompression error
3139 -7 common/cmd_bootm.c Unimplemented compression type
3140 7 common/cmd_bootm.c Uncompression OK
3141 8 common/cmd_bootm.c No uncompress/copy overwrite error
3142 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
3144 9 common/image.c Start initial ramdisk verification
3145 -10 common/image.c Ramdisk header has bad magic number
3146 -11 common/image.c Ramdisk header has bad checksum
3147 10 common/image.c Ramdisk header is OK
3148 -12 common/image.c Ramdisk data has bad checksum
3149 11 common/image.c Ramdisk data has correct checksum
3150 12 common/image.c Ramdisk verification complete, start loading
3151 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
3152 13 common/image.c Start multifile image verification
3153 14 common/image.c No initial ramdisk, no multifile, continue.
3155 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
3157 -30 arch/powerpc/lib/board.c Fatal error, hang the system
3158 -31 post/post.c POST test failed, detected by post_output_backlog()
3159 -32 post/post.c POST test failed, detected by post_run_single()
3161 34 common/cmd_doc.c before loading a Image from a DOC device
3162 -35 common/cmd_doc.c Bad usage of "doc" command
3163 35 common/cmd_doc.c correct usage of "doc" command
3164 -36 common/cmd_doc.c No boot device
3165 36 common/cmd_doc.c correct boot device
3166 -37 common/cmd_doc.c Unknown Chip ID on boot device
3167 37 common/cmd_doc.c correct chip ID found, device available
3168 -38 common/cmd_doc.c Read Error on boot device
3169 38 common/cmd_doc.c reading Image header from DOC device OK
3170 -39 common/cmd_doc.c Image header has bad magic number
3171 39 common/cmd_doc.c Image header has correct magic number
3172 -40 common/cmd_doc.c Error reading Image from DOC device
3173 40 common/cmd_doc.c Image header has correct magic number
3174 41 common/cmd_ide.c before loading a Image from a IDE device
3175 -42 common/cmd_ide.c Bad usage of "ide" command
3176 42 common/cmd_ide.c correct usage of "ide" command
3177 -43 common/cmd_ide.c No boot device
3178 43 common/cmd_ide.c boot device found
3179 -44 common/cmd_ide.c Device not available
3180 44 common/cmd_ide.c Device available
3181 -45 common/cmd_ide.c wrong partition selected
3182 45 common/cmd_ide.c partition selected
3183 -46 common/cmd_ide.c Unknown partition table
3184 46 common/cmd_ide.c valid partition table found
3185 -47 common/cmd_ide.c Invalid partition type
3186 47 common/cmd_ide.c correct partition type
3187 -48 common/cmd_ide.c Error reading Image Header on boot device
3188 48 common/cmd_ide.c reading Image Header from IDE device OK
3189 -49 common/cmd_ide.c Image header has bad magic number
3190 49 common/cmd_ide.c Image header has correct magic number
3191 -50 common/cmd_ide.c Image header has bad checksum
3192 50 common/cmd_ide.c Image header has correct checksum
3193 -51 common/cmd_ide.c Error reading Image from IDE device
3194 51 common/cmd_ide.c reading Image from IDE device OK
3195 52 common/cmd_nand.c before loading a Image from a NAND device
3196 -53 common/cmd_nand.c Bad usage of "nand" command
3197 53 common/cmd_nand.c correct usage of "nand" command
3198 -54 common/cmd_nand.c No boot device
3199 54 common/cmd_nand.c boot device found
3200 -55 common/cmd_nand.c Unknown Chip ID on boot device
3201 55 common/cmd_nand.c correct chip ID found, device available
3202 -56 common/cmd_nand.c Error reading Image Header on boot device
3203 56 common/cmd_nand.c reading Image Header from NAND device OK
3204 -57 common/cmd_nand.c Image header has bad magic number
3205 57 common/cmd_nand.c Image header has correct magic number
3206 -58 common/cmd_nand.c Error reading Image from NAND device
3207 58 common/cmd_nand.c reading Image from NAND device OK
3209 -60 common/env_common.c Environment has a bad CRC, using default
3211 64 net/eth.c starting with Ethernet configuration.
3212 -64 net/eth.c no Ethernet found.
3213 65 net/eth.c Ethernet found.
3215 -80 common/cmd_net.c usage wrong
3216 80 common/cmd_net.c before calling NetLoop()
3217 -81 common/cmd_net.c some error in NetLoop() occurred
3218 81 common/cmd_net.c NetLoop() back without error
3219 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
3220 82 common/cmd_net.c trying automatic boot
3221 83 common/cmd_net.c running "source" command
3222 -83 common/cmd_net.c some error in automatic boot or "source" command
3223 84 common/cmd_net.c end without errors
3228 100 common/cmd_bootm.c Kernel FIT Image has correct format
3229 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
3230 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
3231 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
3232 102 common/cmd_bootm.c Kernel unit name specified
3233 -103 common/cmd_bootm.c Can't get kernel subimage node offset
3234 103 common/cmd_bootm.c Found configuration node
3235 104 common/cmd_bootm.c Got kernel subimage node offset
3236 -104 common/cmd_bootm.c Kernel subimage hash verification failed
3237 105 common/cmd_bootm.c Kernel subimage hash verification OK
3238 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
3239 106 common/cmd_bootm.c Architecture check OK
3240 -106 common/cmd_bootm.c Kernel subimage has wrong type
3241 107 common/cmd_bootm.c Kernel subimage type OK
3242 -107 common/cmd_bootm.c Can't get kernel subimage data/size
3243 108 common/cmd_bootm.c Got kernel subimage data/size
3244 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
3245 -109 common/cmd_bootm.c Can't get kernel subimage type
3246 -110 common/cmd_bootm.c Can't get kernel subimage comp
3247 -111 common/cmd_bootm.c Can't get kernel subimage os
3248 -112 common/cmd_bootm.c Can't get kernel subimage load address
3249 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
3251 120 common/image.c Start initial ramdisk verification
3252 -120 common/image.c Ramdisk FIT image has incorrect format
3253 121 common/image.c Ramdisk FIT image has correct format
3254 122 common/image.c No ramdisk subimage unit name, using configuration
3255 -122 common/image.c Can't get configuration for ramdisk subimage
3256 123 common/image.c Ramdisk unit name specified
3257 -124 common/image.c Can't get ramdisk subimage node offset
3258 125 common/image.c Got ramdisk subimage node offset
3259 -125 common/image.c Ramdisk subimage hash verification failed
3260 126 common/image.c Ramdisk subimage hash verification OK
3261 -126 common/image.c Ramdisk subimage for unsupported architecture
3262 127 common/image.c Architecture check OK
3263 -127 common/image.c Can't get ramdisk subimage data/size
3264 128 common/image.c Got ramdisk subimage data/size
3265 129 common/image.c Can't get ramdisk load address
3266 -129 common/image.c Got ramdisk load address
3268 -130 common/cmd_doc.c Incorrect FIT image format
3269 131 common/cmd_doc.c FIT image format OK
3271 -140 common/cmd_ide.c Incorrect FIT image format
3272 141 common/cmd_ide.c FIT image format OK
3274 -150 common/cmd_nand.c Incorrect FIT image format
3275 151 common/cmd_nand.c FIT image format OK
3277 - legacy image format:
3278 CONFIG_IMAGE_FORMAT_LEGACY
3279 enables the legacy image format support in U-Boot.
3282 enabled if CONFIG_FIT_SIGNATURE is not defined.
3284 CONFIG_DISABLE_IMAGE_LEGACY
3285 disable the legacy image format
3287 This define is introduced, as the legacy image format is
3288 enabled per default for backward compatibility.
3290 - FIT image support:
3292 Enable support for the FIT uImage format.
3294 CONFIG_FIT_BEST_MATCH
3295 When no configuration is explicitly selected, default to the
3296 one whose fdt's compatibility field best matches that of
3297 U-Boot itself. A match is considered "best" if it matches the
3298 most specific compatibility entry of U-Boot's fdt's root node.
3299 The order of entries in the configuration's fdt is ignored.
3301 CONFIG_FIT_SIGNATURE
3302 This option enables signature verification of FIT uImages,
3303 using a hash signed and verified using RSA. See
3304 doc/uImage.FIT/signature.txt for more details.
3306 WARNING: When relying on signed FIT images with required
3307 signature check the legacy image format is default
3308 disabled. If a board need legacy image format support
3309 enable this through CONFIG_IMAGE_FORMAT_LEGACY
3311 CONFIG_FIT_DISABLE_SHA256
3312 Supporting SHA256 hashes has quite an impact on binary size.
3313 For constrained systems sha256 hash support can be disabled
3316 - Standalone program support:
3317 CONFIG_STANDALONE_LOAD_ADDR
3319 This option defines a board specific value for the
3320 address where standalone program gets loaded, thus
3321 overwriting the architecture dependent default
3324 - Frame Buffer Address:
3327 Define CONFIG_FB_ADDR if you want to use specific
3328 address for frame buffer. This is typically the case
3329 when using a graphics controller has separate video
3330 memory. U-Boot will then place the frame buffer at
3331 the given address instead of dynamically reserving it
3332 in system RAM by calling lcd_setmem(), which grabs
3333 the memory for the frame buffer depending on the
3334 configured panel size.
3336 Please see board_init_f function.
3338 - Automatic software updates via TFTP server
3340 CONFIG_UPDATE_TFTP_CNT_MAX
3341 CONFIG_UPDATE_TFTP_MSEC_MAX
3343 These options enable and control the auto-update feature;
3344 for a more detailed description refer to doc/README.update.
3346 - MTD Support (mtdparts command, UBI support)
3349 Adds the MTD device infrastructure from the Linux kernel.
3350 Needed for mtdparts command support.
3352 CONFIG_MTD_PARTITIONS
3354 Adds the MTD partitioning infrastructure from the Linux
3355 kernel. Needed for UBI support.
3357 CONFIG_MTD_NAND_VERIFY_WRITE
3358 verify if the written data is correct reread.
3363 Adds commands for interacting with MTD partitions formatted
3364 with the UBI flash translation layer
3366 Requires also defining CONFIG_RBTREE
3368 CONFIG_UBI_SILENCE_MSG
3370 Make the verbose messages from UBI stop printing. This leaves
3371 warnings and errors enabled.
3374 CONFIG_MTD_UBI_WL_THRESHOLD
3375 This parameter defines the maximum difference between the highest
3376 erase counter value and the lowest erase counter value of eraseblocks
3377 of UBI devices. When this threshold is exceeded, UBI starts performing
3378 wear leveling by means of moving data from eraseblock with low erase
3379 counter to eraseblocks with high erase counter.
3381 The default value should be OK for SLC NAND flashes, NOR flashes and
3382 other flashes which have eraseblock life-cycle 100000 or more.
3383 However, in case of MLC NAND flashes which typically have eraseblock
3384 life-cycle less than 10000, the threshold should be lessened (e.g.,
3385 to 128 or 256, although it does not have to be power of 2).
3389 CONFIG_MTD_UBI_BEB_LIMIT
3390 This option specifies the maximum bad physical eraseblocks UBI
3391 expects on the MTD device (per 1024 eraseblocks). If the
3392 underlying flash does not admit of bad eraseblocks (e.g. NOR
3393 flash), this value is ignored.
3395 NAND datasheets often specify the minimum and maximum NVM
3396 (Number of Valid Blocks) for the flashes' endurance lifetime.
3397 The maximum expected bad eraseblocks per 1024 eraseblocks
3398 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
3399 which gives 20 for most NANDs (MaxNVB is basically the total
3400 count of eraseblocks on the chip).
3402 To put it differently, if this value is 20, UBI will try to
3403 reserve about 1.9% of physical eraseblocks for bad blocks
3404 handling. And that will be 1.9% of eraseblocks on the entire
3405 NAND chip, not just the MTD partition UBI attaches. This means
3406 that if you have, say, a NAND flash chip admits maximum 40 bad
3407 eraseblocks, and it is split on two MTD partitions of the same
3408 size, UBI will reserve 40 eraseblocks when attaching a
3413 CONFIG_MTD_UBI_FASTMAP
3414 Fastmap is a mechanism which allows attaching an UBI device
3415 in nearly constant time. Instead of scanning the whole MTD device it
3416 only has to locate a checkpoint (called fastmap) on the device.
3417 The on-flash fastmap contains all information needed to attach
3418 the device. Using fastmap makes only sense on large devices where
3419 attaching by scanning takes long. UBI will not automatically install
3420 a fastmap on old images, but you can set the UBI parameter
3421 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
3422 that fastmap-enabled images are still usable with UBI implementations
3423 without fastmap support. On typical flash devices the whole fastmap
3424 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
3426 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
3427 Set this parameter to enable fastmap automatically on images
3434 Adds commands for interacting with UBI volumes formatted as
3435 UBIFS. UBIFS is read-only in u-boot.
3437 Requires UBI support as well as CONFIG_LZO
3439 CONFIG_UBIFS_SILENCE_MSG
3441 Make the verbose messages from UBIFS stop printing. This leaves
3442 warnings and errors enabled.
3446 Enable building of SPL globally.
3449 LDSCRIPT for linking the SPL binary.
3451 CONFIG_SPL_MAX_FOOTPRINT
3452 Maximum size in memory allocated to the SPL, BSS included.
3453 When defined, the linker checks that the actual memory
3454 used by SPL from _start to __bss_end does not exceed it.
3455 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3456 must not be both defined at the same time.
3459 Maximum size of the SPL image (text, data, rodata, and
3460 linker lists sections), BSS excluded.
3461 When defined, the linker checks that the actual size does
3464 CONFIG_SPL_TEXT_BASE
3465 TEXT_BASE for linking the SPL binary.
3467 CONFIG_SPL_RELOC_TEXT_BASE
3468 Address to relocate to. If unspecified, this is equal to
3469 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3471 CONFIG_SPL_BSS_START_ADDR
3472 Link address for the BSS within the SPL binary.
3474 CONFIG_SPL_BSS_MAX_SIZE
3475 Maximum size in memory allocated to the SPL BSS.
3476 When defined, the linker checks that the actual memory used
3477 by SPL from __bss_start to __bss_end does not exceed it.
3478 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3479 must not be both defined at the same time.
3482 Adress of the start of the stack SPL will use
3484 CONFIG_SPL_RELOC_STACK
3485 Adress of the start of the stack SPL will use after
3486 relocation. If unspecified, this is equal to
3489 CONFIG_SYS_SPL_MALLOC_START
3490 Starting address of the malloc pool used in SPL.
3492 CONFIG_SYS_SPL_MALLOC_SIZE
3493 The size of the malloc pool used in SPL.
3495 CONFIG_SPL_FRAMEWORK
3496 Enable the SPL framework under common/. This framework
3497 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3498 NAND loading of the Linux Kernel.
3501 Enable booting directly to an OS from SPL.
3502 See also: doc/README.falcon
3504 CONFIG_SPL_DISPLAY_PRINT
3505 For ARM, enable an optional function to print more information
3506 about the running system.
3508 CONFIG_SPL_INIT_MINIMAL
3509 Arch init code should be built for a very small image
3511 CONFIG_SPL_LIBCOMMON_SUPPORT
3512 Support for common/libcommon.o in SPL binary
3514 CONFIG_SPL_LIBDISK_SUPPORT
3515 Support for disk/libdisk.o in SPL binary
3517 CONFIG_SPL_I2C_SUPPORT
3518 Support for drivers/i2c/libi2c.o in SPL binary
3520 CONFIG_SPL_GPIO_SUPPORT
3521 Support for drivers/gpio/libgpio.o in SPL binary
3523 CONFIG_SPL_MMC_SUPPORT
3524 Support for drivers/mmc/libmmc.o in SPL binary
3526 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3527 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3528 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3529 Address, size and partition on the MMC to load U-Boot from
3530 when the MMC is being used in raw mode.
3532 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3533 Sector to load kernel uImage from when MMC is being
3534 used in raw mode (for Falcon mode)
3536 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3537 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3538 Sector and number of sectors to load kernel argument
3539 parameters from when MMC is being used in raw mode
3542 CONFIG_SPL_FAT_SUPPORT
3543 Support for fs/fat/libfat.o in SPL binary
3545 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3546 Filename to read to load U-Boot when reading from FAT
3548 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3549 Filename to read to load kernel uImage when reading
3550 from FAT (for Falcon mode)
3552 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3553 Filename to read to load kernel argument parameters
3554 when reading from FAT (for Falcon mode)
3556 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3557 Set this for NAND SPL on PPC mpc83xx targets, so that
3558 start.S waits for the rest of the SPL to load before
3559 continuing (the hardware starts execution after just
3560 loading the first page rather than the full 4K).
3562 CONFIG_SPL_SKIP_RELOCATE
3563 Avoid SPL relocation
3565 CONFIG_SPL_NAND_BASE
3566 Include nand_base.c in the SPL. Requires
3567 CONFIG_SPL_NAND_DRIVERS.
3569 CONFIG_SPL_NAND_DRIVERS
3570 SPL uses normal NAND drivers, not minimal drivers.
3573 Include standard software ECC in the SPL
3575 CONFIG_SPL_NAND_SIMPLE
3576 Support for NAND boot using simple NAND drivers that
3577 expose the cmd_ctrl() interface.
3579 CONFIG_SPL_MTD_SUPPORT
3580 Support for the MTD subsystem within SPL. Useful for
3581 environment on NAND support within SPL.
3583 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3584 Set for the SPL on PPC mpc8xxx targets, support for
3585 drivers/ddr/fsl/libddr.o in SPL binary.
3587 CONFIG_SPL_COMMON_INIT_DDR
3588 Set for common ddr init with serial presence detect in
3591 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3592 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3593 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3594 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3595 CONFIG_SYS_NAND_ECCBYTES
3596 Defines the size and behavior of the NAND that SPL uses
3599 CONFIG_SPL_NAND_BOOT
3600 Add support NAND boot
3602 CONFIG_SYS_NAND_U_BOOT_OFFS
3603 Location in NAND to read U-Boot from
3605 CONFIG_SYS_NAND_U_BOOT_DST
3606 Location in memory to load U-Boot to
3608 CONFIG_SYS_NAND_U_BOOT_SIZE
3609 Size of image to load
3611 CONFIG_SYS_NAND_U_BOOT_START
3612 Entry point in loaded image to jump to
3614 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3615 Define this if you need to first read the OOB and then the
3616 data. This is used for example on davinci plattforms.
3618 CONFIG_SPL_OMAP3_ID_NAND
3619 Support for an OMAP3-specific set of functions to return the
3620 ID and MFR of the first attached NAND chip, if present.
3622 CONFIG_SPL_SERIAL_SUPPORT
3623 Support for drivers/serial/libserial.o in SPL binary
3625 CONFIG_SPL_SPI_FLASH_SUPPORT
3626 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3628 CONFIG_SPL_SPI_SUPPORT
3629 Support for drivers/spi/libspi.o in SPL binary
3631 CONFIG_SPL_RAM_DEVICE
3632 Support for running image already present in ram, in SPL binary
3634 CONFIG_SPL_LIBGENERIC_SUPPORT
3635 Support for lib/libgeneric.o in SPL binary
3637 CONFIG_SPL_ENV_SUPPORT
3638 Support for the environment operating in SPL binary
3640 CONFIG_SPL_NET_SUPPORT
3641 Support for the net/libnet.o in SPL binary.
3642 It conflicts with SPL env from storage medium specified by
3643 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3646 Image offset to which the SPL should be padded before appending
3647 the SPL payload. By default, this is defined as
3648 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3649 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3650 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3653 Final target image containing SPL and payload. Some SPLs
3654 use an arch-specific makefile fragment instead, for
3655 example if more than one image needs to be produced.
3657 CONFIG_FIT_SPL_PRINT
3658 Printing information about a FIT image adds quite a bit of
3659 code to SPL. So this is normally disabled in SPL. Use this
3660 option to re-enable it. This will affect the output of the
3661 bootm command when booting a FIT image.
3665 Enable building of TPL globally.
3668 Image offset to which the TPL should be padded before appending
3669 the TPL payload. By default, this is defined as
3670 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3671 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3672 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3677 [so far only for SMDK2400 boards]
3679 - Modem support enable:
3680 CONFIG_MODEM_SUPPORT
3682 - RTS/CTS Flow control enable:
3685 - Modem debug support:
3686 CONFIG_MODEM_SUPPORT_DEBUG
3688 Enables debugging stuff (char screen[1024], dbg())
3689 for modem support. Useful only with BDI2000.
3691 - Interrupt support (PPC):
3693 There are common interrupt_init() and timer_interrupt()
3694 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3695 for CPU specific initialization. interrupt_init_cpu()
3696 should set decrementer_count to appropriate value. If
3697 CPU resets decrementer automatically after interrupt
3698 (ppc4xx) it should set decrementer_count to zero.
3699 timer_interrupt() calls timer_interrupt_cpu() for CPU
3700 specific handling. If board has watchdog / status_led
3701 / other_activity_monitor it works automatically from
3702 general timer_interrupt().
3706 In the target system modem support is enabled when a
3707 specific key (key combination) is pressed during
3708 power-on. Otherwise U-Boot will boot normally
3709 (autoboot). The key_pressed() function is called from
3710 board_init(). Currently key_pressed() is a dummy
3711 function, returning 1 and thus enabling modem
3714 If there are no modem init strings in the
3715 environment, U-Boot proceed to autoboot; the
3716 previous output (banner, info printfs) will be
3719 See also: doc/README.Modem
3721 Board initialization settings:
3722 ------------------------------
3724 During Initialization u-boot calls a number of board specific functions
3725 to allow the preparation of board specific prerequisites, e.g. pin setup
3726 before drivers are initialized. To enable these callbacks the
3727 following configuration macros have to be defined. Currently this is
3728 architecture specific, so please check arch/your_architecture/lib/board.c
3729 typically in board_init_f() and board_init_r().
3731 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3732 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3733 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3734 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3736 Configuration Settings:
3737 -----------------------
3739 - CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
3740 Optionally it can be defined to support 64-bit memory commands.
3742 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3743 undefine this when you're short of memory.
3745 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3746 width of the commands listed in the 'help' command output.
3748 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3749 prompt for user input.
3751 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3753 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3755 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3757 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3758 the application (usually a Linux kernel) when it is
3761 - CONFIG_SYS_BAUDRATE_TABLE:
3762 List of legal baudrate settings for this board.
3764 - CONFIG_SYS_CONSOLE_INFO_QUIET
3765 Suppress display of console information at boot.
3767 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3768 If the board specific function
3769 extern int overwrite_console (void);
3770 returns 1, the stdin, stderr and stdout are switched to the
3771 serial port, else the settings in the environment are used.
3773 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3774 Enable the call to overwrite_console().
3776 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3777 Enable overwrite of previous console environment settings.
3779 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3780 Begin and End addresses of the area used by the
3783 - CONFIG_SYS_ALT_MEMTEST:
3784 Enable an alternate, more extensive memory test.
3786 - CONFIG_SYS_MEMTEST_SCRATCH:
3787 Scratch address used by the alternate memory test
3788 You only need to set this if address zero isn't writeable
3790 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3791 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3792 this specified memory area will get subtracted from the top
3793 (end) of RAM and won't get "touched" at all by U-Boot. By
3794 fixing up gd->ram_size the Linux kernel should gets passed
3795 the now "corrected" memory size and won't touch it either.
3796 This should work for arch/ppc and arch/powerpc. Only Linux
3797 board ports in arch/powerpc with bootwrapper support that
3798 recalculate the memory size from the SDRAM controller setup
3799 will have to get fixed in Linux additionally.
3801 This option can be used as a workaround for the 440EPx/GRx
3802 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3805 WARNING: Please make sure that this value is a multiple of
3806 the Linux page size (normally 4k). If this is not the case,
3807 then the end address of the Linux memory will be located at a
3808 non page size aligned address and this could cause major
3811 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3812 Enable temporary baudrate change while serial download
3814 - CONFIG_SYS_SDRAM_BASE:
3815 Physical start address of SDRAM. _Must_ be 0 here.
3817 - CONFIG_SYS_MBIO_BASE:
3818 Physical start address of Motherboard I/O (if using a
3821 - CONFIG_SYS_FLASH_BASE:
3822 Physical start address of Flash memory.
3824 - CONFIG_SYS_MONITOR_BASE:
3825 Physical start address of boot monitor code (set by
3826 make config files to be same as the text base address
3827 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3828 CONFIG_SYS_FLASH_BASE when booting from flash.
3830 - CONFIG_SYS_MONITOR_LEN:
3831 Size of memory reserved for monitor code, used to
3832 determine _at_compile_time_ (!) if the environment is
3833 embedded within the U-Boot image, or in a separate
3836 - CONFIG_SYS_MALLOC_LEN:
3837 Size of DRAM reserved for malloc() use.
3839 - CONFIG_SYS_MALLOC_F_LEN
3840 Size of the malloc() pool for use before relocation. If
3841 this is defined, then a very simple malloc() implementation
3842 will become available before relocation. The address is just
3843 below the global data, and the stack is moved down to make
3846 This feature allocates regions with increasing addresses
3847 within the region. calloc() is supported, but realloc()
3848 is not available. free() is supported but does nothing.
3849 The memory will be freed (or in fact just forgotton) when
3850 U-Boot relocates itself.
3852 Pre-relocation malloc() is only supported on sandbox
3853 at present but is fairly easy to enable for other archs.
3855 Pre-relocation malloc() is only supported on ARM at present
3856 but is fairly easy to enable for other archs.
3858 - CONFIG_SYS_BOOTM_LEN:
3859 Normally compressed uImages are limited to an
3860 uncompressed size of 8 MBytes. If this is not enough,
3861 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3862 to adjust this setting to your needs.
3864 - CONFIG_SYS_BOOTMAPSZ:
3865 Maximum size of memory mapped by the startup code of
3866 the Linux kernel; all data that must be processed by
3867 the Linux kernel (bd_info, boot arguments, FDT blob if
3868 used) must be put below this limit, unless "bootm_low"
3869 environment variable is defined and non-zero. In such case
3870 all data for the Linux kernel must be between "bootm_low"
3871 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3872 variable "bootm_mapsize" will override the value of
3873 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3874 then the value in "bootm_size" will be used instead.
3876 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3877 Enable initrd_high functionality. If defined then the
3878 initrd_high feature is enabled and the bootm ramdisk subcommand
3881 - CONFIG_SYS_BOOT_GET_CMDLINE:
3882 Enables allocating and saving kernel cmdline in space between
3883 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3885 - CONFIG_SYS_BOOT_GET_KBD:
3886 Enables allocating and saving a kernel copy of the bd_info in
3887 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3889 - CONFIG_SYS_MAX_FLASH_BANKS:
3890 Max number of Flash memory banks
3892 - CONFIG_SYS_MAX_FLASH_SECT:
3893 Max number of sectors on a Flash chip
3895 - CONFIG_SYS_FLASH_ERASE_TOUT:
3896 Timeout for Flash erase operations (in ms)
3898 - CONFIG_SYS_FLASH_WRITE_TOUT:
3899 Timeout for Flash write operations (in ms)
3901 - CONFIG_SYS_FLASH_LOCK_TOUT
3902 Timeout for Flash set sector lock bit operation (in ms)
3904 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3905 Timeout for Flash clear lock bits operation (in ms)
3907 - CONFIG_SYS_FLASH_PROTECTION
3908 If defined, hardware flash sectors protection is used
3909 instead of U-Boot software protection.
3911 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3913 Enable TFTP transfers directly to flash memory;
3914 without this option such a download has to be
3915 performed in two steps: (1) download to RAM, and (2)
3916 copy from RAM to flash.
3918 The two-step approach is usually more reliable, since
3919 you can check if the download worked before you erase
3920 the flash, but in some situations (when system RAM is
3921 too limited to allow for a temporary copy of the
3922 downloaded image) this option may be very useful.
3924 - CONFIG_SYS_FLASH_CFI:
3925 Define if the flash driver uses extra elements in the
3926 common flash structure for storing flash geometry.
3928 - CONFIG_FLASH_CFI_DRIVER
3929 This option also enables the building of the cfi_flash driver
3930 in the drivers directory
3932 - CONFIG_FLASH_CFI_MTD
3933 This option enables the building of the cfi_mtd driver
3934 in the drivers directory. The driver exports CFI flash
3937 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3938 Use buffered writes to flash.
3940 - CONFIG_FLASH_SPANSION_S29WS_N
3941 s29ws-n MirrorBit flash has non-standard addresses for buffered
3944 - CONFIG_SYS_FLASH_QUIET_TEST
3945 If this option is defined, the common CFI flash doesn't
3946 print it's warning upon not recognized FLASH banks. This
3947 is useful, if some of the configured banks are only
3948 optionally available.
3950 - CONFIG_FLASH_SHOW_PROGRESS
3951 If defined (must be an integer), print out countdown
3952 digits and dots. Recommended value: 45 (9..1) for 80
3953 column displays, 15 (3..1) for 40 column displays.
3955 - CONFIG_FLASH_VERIFY
3956 If defined, the content of the flash (destination) is compared
3957 against the source after the write operation. An error message
3958 will be printed when the contents are not identical.
3959 Please note that this option is useless in nearly all cases,
3960 since such flash programming errors usually are detected earlier
3961 while unprotecting/erasing/programming. Please only enable
3962 this option if you really know what you are doing.
3964 - CONFIG_SYS_RX_ETH_BUFFER:
3965 Defines the number of Ethernet receive buffers. On some
3966 Ethernet controllers it is recommended to set this value
3967 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3968 buffers can be full shortly after enabling the interface
3969 on high Ethernet traffic.
3970 Defaults to 4 if not defined.
3972 - CONFIG_ENV_MAX_ENTRIES
3974 Maximum number of entries in the hash table that is used
3975 internally to store the environment settings. The default
3976 setting is supposed to be generous and should work in most
3977 cases. This setting can be used to tune behaviour; see
3978 lib/hashtable.c for details.
3980 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3981 - CONFIG_ENV_FLAGS_LIST_STATIC
3982 Enable validation of the values given to environment variables when
3983 calling env set. Variables can be restricted to only decimal,
3984 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3985 the variables can also be restricted to IP address or MAC address.
3987 The format of the list is:
3988 type_attribute = [s|d|x|b|i|m]
3989 access_atribute = [a|r|o|c]
3990 attributes = type_attribute[access_atribute]
3991 entry = variable_name[:attributes]
3994 The type attributes are:
3995 s - String (default)
3998 b - Boolean ([1yYtT|0nNfF])
4002 The access attributes are:
4008 - CONFIG_ENV_FLAGS_LIST_DEFAULT
4009 Define this to a list (string) to define the ".flags"
4010 envirnoment variable in the default or embedded environment.
4012 - CONFIG_ENV_FLAGS_LIST_STATIC
4013 Define this to a list (string) to define validation that
4014 should be done if an entry is not found in the ".flags"
4015 environment variable. To override a setting in the static
4016 list, simply add an entry for the same variable name to the
4019 - CONFIG_ENV_ACCESS_IGNORE_FORCE
4020 If defined, don't allow the -f switch to env set override variable
4023 - CONFIG_SYS_GENERIC_BOARD
4024 This selects the architecture-generic board system instead of the
4025 architecture-specific board files. It is intended to move boards
4026 to this new framework over time. Defining this will disable the
4027 arch/foo/lib/board.c file and use common/board_f.c and
4028 common/board_r.c instead. To use this option your architecture
4029 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
4030 its config.mk file). If you find problems enabling this option on
4031 your board please report the problem and send patches!
4033 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
4034 This is set by OMAP boards for the max time that reset should
4035 be asserted. See doc/README.omap-reset-time for details on how
4036 the value can be calulated on a given board.
4038 The following definitions that deal with the placement and management
4039 of environment data (variable area); in general, we support the
4040 following configurations:
4042 - CONFIG_BUILD_ENVCRC:
4044 Builds up envcrc with the target environment so that external utils
4045 may easily extract it and embed it in final U-Boot images.
4047 - CONFIG_ENV_IS_IN_FLASH:
4049 Define this if the environment is in flash memory.
4051 a) The environment occupies one whole flash sector, which is
4052 "embedded" in the text segment with the U-Boot code. This
4053 happens usually with "bottom boot sector" or "top boot
4054 sector" type flash chips, which have several smaller
4055 sectors at the start or the end. For instance, such a
4056 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
4057 such a case you would place the environment in one of the
4058 4 kB sectors - with U-Boot code before and after it. With
4059 "top boot sector" type flash chips, you would put the
4060 environment in one of the last sectors, leaving a gap
4061 between U-Boot and the environment.
4063 - CONFIG_ENV_OFFSET:
4065 Offset of environment data (variable area) to the
4066 beginning of flash memory; for instance, with bottom boot
4067 type flash chips the second sector can be used: the offset
4068 for this sector is given here.
4070 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
4074 This is just another way to specify the start address of
4075 the flash sector containing the environment (instead of
4078 - CONFIG_ENV_SECT_SIZE:
4080 Size of the sector containing the environment.
4083 b) Sometimes flash chips have few, equal sized, BIG sectors.
4084 In such a case you don't want to spend a whole sector for
4089 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
4090 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
4091 of this flash sector for the environment. This saves
4092 memory for the RAM copy of the environment.
4094 It may also save flash memory if you decide to use this
4095 when your environment is "embedded" within U-Boot code,
4096 since then the remainder of the flash sector could be used
4097 for U-Boot code. It should be pointed out that this is
4098 STRONGLY DISCOURAGED from a robustness point of view:
4099 updating the environment in flash makes it always
4100 necessary to erase the WHOLE sector. If something goes
4101 wrong before the contents has been restored from a copy in
4102 RAM, your target system will be dead.
4104 - CONFIG_ENV_ADDR_REDUND
4105 CONFIG_ENV_SIZE_REDUND
4107 These settings describe a second storage area used to hold
4108 a redundant copy of the environment data, so that there is
4109 a valid backup copy in case there is a power failure during
4110 a "saveenv" operation.
4112 BE CAREFUL! Any changes to the flash layout, and some changes to the
4113 source code will make it necessary to adapt <board>/u-boot.lds*
4117 - CONFIG_ENV_IS_IN_NVRAM:
4119 Define this if you have some non-volatile memory device
4120 (NVRAM, battery buffered SRAM) which you want to use for the
4126 These two #defines are used to determine the memory area you
4127 want to use for environment. It is assumed that this memory
4128 can just be read and written to, without any special
4131 BE CAREFUL! The first access to the environment happens quite early
4132 in U-Boot initalization (when we try to get the setting of for the
4133 console baudrate). You *MUST* have mapped your NVRAM area then, or
4136 Please note that even with NVRAM we still use a copy of the
4137 environment in RAM: we could work on NVRAM directly, but we want to
4138 keep settings there always unmodified except somebody uses "saveenv"
4139 to save the current settings.
4142 - CONFIG_ENV_IS_IN_EEPROM:
4144 Use this if you have an EEPROM or similar serial access
4145 device and a driver for it.
4147 - CONFIG_ENV_OFFSET:
4150 These two #defines specify the offset and size of the
4151 environment area within the total memory of your EEPROM.
4153 - CONFIG_SYS_I2C_EEPROM_ADDR:
4154 If defined, specified the chip address of the EEPROM device.
4155 The default address is zero.
4157 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
4158 If defined, the number of bits used to address bytes in a
4159 single page in the EEPROM device. A 64 byte page, for example
4160 would require six bits.
4162 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
4163 If defined, the number of milliseconds to delay between
4164 page writes. The default is zero milliseconds.
4166 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
4167 The length in bytes of the EEPROM memory array address. Note
4168 that this is NOT the chip address length!
4170 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
4171 EEPROM chips that implement "address overflow" are ones
4172 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
4173 address and the extra bits end up in the "chip address" bit
4174 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
4177 Note that we consider the length of the address field to
4178 still be one byte because the extra address bits are hidden
4179 in the chip address.
4181 - CONFIG_SYS_EEPROM_SIZE:
4182 The size in bytes of the EEPROM device.
4184 - CONFIG_ENV_EEPROM_IS_ON_I2C
4185 define this, if you have I2C and SPI activated, and your
4186 EEPROM, which holds the environment, is on the I2C bus.
4188 - CONFIG_I2C_ENV_EEPROM_BUS
4189 if you have an Environment on an EEPROM reached over
4190 I2C muxes, you can define here, how to reach this
4191 EEPROM. For example:
4193 #define CONFIG_I2C_ENV_EEPROM_BUS 1
4195 EEPROM which holds the environment, is reached over
4196 a pca9547 i2c mux with address 0x70, channel 3.
4198 - CONFIG_ENV_IS_IN_DATAFLASH:
4200 Define this if you have a DataFlash memory device which you
4201 want to use for the environment.
4203 - CONFIG_ENV_OFFSET:
4207 These three #defines specify the offset and size of the
4208 environment area within the total memory of your DataFlash placed
4209 at the specified address.
4211 - CONFIG_ENV_IS_IN_SPI_FLASH:
4213 Define this if you have a SPI Flash memory device which you
4214 want to use for the environment.
4216 - CONFIG_ENV_OFFSET:
4219 These two #defines specify the offset and size of the
4220 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
4221 aligned to an erase sector boundary.
4223 - CONFIG_ENV_SECT_SIZE:
4225 Define the SPI flash's sector size.
4227 - CONFIG_ENV_OFFSET_REDUND (optional):
4229 This setting describes a second storage area of CONFIG_ENV_SIZE
4230 size used to hold a redundant copy of the environment data, so
4231 that there is a valid backup copy in case there is a power failure
4232 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4233 aligned to an erase sector boundary.
4235 - CONFIG_ENV_SPI_BUS (optional):
4236 - CONFIG_ENV_SPI_CS (optional):
4238 Define the SPI bus and chip select. If not defined they will be 0.
4240 - CONFIG_ENV_SPI_MAX_HZ (optional):
4242 Define the SPI max work clock. If not defined then use 1MHz.
4244 - CONFIG_ENV_SPI_MODE (optional):
4246 Define the SPI work mode. If not defined then use SPI_MODE_3.
4248 - CONFIG_ENV_IS_IN_REMOTE:
4250 Define this if you have a remote memory space which you
4251 want to use for the local device's environment.
4256 These two #defines specify the address and size of the
4257 environment area within the remote memory space. The
4258 local device can get the environment from remote memory
4259 space by SRIO or PCIE links.
4261 BE CAREFUL! For some special cases, the local device can not use
4262 "saveenv" command. For example, the local device will get the
4263 environment stored in a remote NOR flash by SRIO or PCIE link,
4264 but it can not erase, write this NOR flash by SRIO or PCIE interface.
4266 - CONFIG_ENV_IS_IN_NAND:
4268 Define this if you have a NAND device which you want to use
4269 for the environment.
4271 - CONFIG_ENV_OFFSET:
4274 These two #defines specify the offset and size of the environment
4275 area within the first NAND device. CONFIG_ENV_OFFSET must be
4276 aligned to an erase block boundary.
4278 - CONFIG_ENV_OFFSET_REDUND (optional):
4280 This setting describes a second storage area of CONFIG_ENV_SIZE
4281 size used to hold a redundant copy of the environment data, so
4282 that there is a valid backup copy in case there is a power failure
4283 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
4284 aligned to an erase block boundary.
4286 - CONFIG_ENV_RANGE (optional):
4288 Specifies the length of the region in which the environment
4289 can be written. This should be a multiple of the NAND device's
4290 block size. Specifying a range with more erase blocks than
4291 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
4292 the range to be avoided.
4294 - CONFIG_ENV_OFFSET_OOB (optional):
4296 Enables support for dynamically retrieving the offset of the
4297 environment from block zero's out-of-band data. The
4298 "nand env.oob" command can be used to record this offset.
4299 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
4300 using CONFIG_ENV_OFFSET_OOB.
4302 - CONFIG_NAND_ENV_DST
4304 Defines address in RAM to which the nand_spl code should copy the
4305 environment. If redundant environment is used, it will be copied to
4306 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
4308 - CONFIG_ENV_IS_IN_UBI:
4310 Define this if you have an UBI volume that you want to use for the
4311 environment. This has the benefit of wear-leveling the environment
4312 accesses, which is important on NAND.
4314 - CONFIG_ENV_UBI_PART:
4316 Define this to a string that is the mtd partition containing the UBI.
4318 - CONFIG_ENV_UBI_VOLUME:
4320 Define this to the name of the volume that you want to store the
4323 - CONFIG_ENV_UBI_VOLUME_REDUND:
4325 Define this to the name of another volume to store a second copy of
4326 the environment in. This will enable redundant environments in UBI.
4327 It is assumed that both volumes are in the same MTD partition.
4329 - CONFIG_UBI_SILENCE_MSG
4330 - CONFIG_UBIFS_SILENCE_MSG
4332 You will probably want to define these to avoid a really noisy system
4333 when storing the env in UBI.
4335 - CONFIG_ENV_IS_IN_FAT:
4336 Define this if you want to use the FAT file system for the environment.
4338 - FAT_ENV_INTERFACE:
4340 Define this to a string that is the name of the block device.
4342 - FAT_ENV_DEV_AND_PART:
4344 Define this to a string to specify the partition of the device. It can
4347 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
4348 - "D:P": device D partition P. Error occurs if device D has no
4351 - "D" or "D:": device D partition 1 if device D has partition
4352 table, or the whole device D if has no partition
4354 - "D:auto": first partition in device D with bootable flag set.
4355 If none, first valid paratition in device D. If no
4356 partition table then means device D.
4360 It's a string of the FAT file name. This file use to store the
4364 This should be defined. Otherwise it cannot save the envrionment file.
4366 - CONFIG_ENV_IS_IN_MMC:
4368 Define this if you have an MMC device which you want to use for the
4371 - CONFIG_SYS_MMC_ENV_DEV:
4373 Specifies which MMC device the environment is stored in.
4375 - CONFIG_SYS_MMC_ENV_PART (optional):
4377 Specifies which MMC partition the environment is stored in. If not
4378 set, defaults to partition 0, the user area. Common values might be
4379 1 (first MMC boot partition), 2 (second MMC boot partition).
4381 - CONFIG_ENV_OFFSET:
4384 These two #defines specify the offset and size of the environment
4385 area within the specified MMC device.
4387 If offset is positive (the usual case), it is treated as relative to
4388 the start of the MMC partition. If offset is negative, it is treated
4389 as relative to the end of the MMC partition. This can be useful if
4390 your board may be fitted with different MMC devices, which have
4391 different sizes for the MMC partitions, and you always want the
4392 environment placed at the very end of the partition, to leave the
4393 maximum possible space before it, to store other data.
4395 These two values are in units of bytes, but must be aligned to an
4396 MMC sector boundary.
4398 - CONFIG_ENV_OFFSET_REDUND (optional):
4400 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
4401 hold a redundant copy of the environment data. This provides a
4402 valid backup copy in case the other copy is corrupted, e.g. due
4403 to a power failure during a "saveenv" operation.
4405 This value may also be positive or negative; this is handled in the
4406 same way as CONFIG_ENV_OFFSET.
4408 This value is also in units of bytes, but must also be aligned to
4409 an MMC sector boundary.
4411 - CONFIG_ENV_SIZE_REDUND (optional):
4413 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
4414 set. If this value is set, it must be set to the same value as
4417 - CONFIG_SYS_SPI_INIT_OFFSET
4419 Defines offset to the initial SPI buffer area in DPRAM. The
4420 area is used at an early stage (ROM part) if the environment
4421 is configured to reside in the SPI EEPROM: We need a 520 byte
4422 scratch DPRAM area. It is used between the two initialization
4423 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
4424 to be a good choice since it makes it far enough from the
4425 start of the data area as well as from the stack pointer.
4427 Please note that the environment is read-only until the monitor
4428 has been relocated to RAM and a RAM copy of the environment has been
4429 created; also, when using EEPROM you will have to use getenv_f()
4430 until then to read environment variables.
4432 The environment is protected by a CRC32 checksum. Before the monitor
4433 is relocated into RAM, as a result of a bad CRC you will be working
4434 with the compiled-in default environment - *silently*!!! [This is
4435 necessary, because the first environment variable we need is the
4436 "baudrate" setting for the console - if we have a bad CRC, we don't
4437 have any device yet where we could complain.]
4439 Note: once the monitor has been relocated, then it will complain if
4440 the default environment is used; a new CRC is computed as soon as you
4441 use the "saveenv" command to store a valid environment.
4443 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
4444 Echo the inverted Ethernet link state to the fault LED.
4446 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
4447 also needs to be defined.
4449 - CONFIG_SYS_FAULT_MII_ADDR:
4450 MII address of the PHY to check for the Ethernet link state.
4452 - CONFIG_NS16550_MIN_FUNCTIONS:
4453 Define this if you desire to only have use of the NS16550_init
4454 and NS16550_putc functions for the serial driver located at
4455 drivers/serial/ns16550.c. This option is useful for saving
4456 space for already greatly restricted images, including but not
4457 limited to NAND_SPL configurations.
4459 - CONFIG_DISPLAY_BOARDINFO
4460 Display information about the board that U-Boot is running on
4461 when U-Boot starts up. The board function checkboard() is called
4464 - CONFIG_DISPLAY_BOARDINFO_LATE
4465 Similar to the previous option, but display this information
4466 later, once stdio is running and output goes to the LCD, if
4469 - CONFIG_BOARD_SIZE_LIMIT:
4470 Maximum size of the U-Boot image. When defined, the
4471 build system checks that the actual size does not
4474 Low Level (hardware related) configuration options:
4475 ---------------------------------------------------
4477 - CONFIG_SYS_CACHELINE_SIZE:
4478 Cache Line Size of the CPU.
4480 - CONFIG_SYS_DEFAULT_IMMR:
4481 Default address of the IMMR after system reset.
4483 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
4484 and RPXsuper) to be able to adjust the position of
4485 the IMMR register after a reset.
4487 - CONFIG_SYS_CCSRBAR_DEFAULT:
4488 Default (power-on reset) physical address of CCSR on Freescale
4491 - CONFIG_SYS_CCSRBAR:
4492 Virtual address of CCSR. On a 32-bit build, this is typically
4493 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
4495 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
4496 for cross-platform code that uses that macro instead.
4498 - CONFIG_SYS_CCSRBAR_PHYS:
4499 Physical address of CCSR. CCSR can be relocated to a new
4500 physical address, if desired. In this case, this macro should
4501 be set to that address. Otherwise, it should be set to the
4502 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
4503 is typically relocated on 36-bit builds. It is recommended
4504 that this macro be defined via the _HIGH and _LOW macros:
4506 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
4507 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
4509 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
4510 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
4511 either 0 (32-bit build) or 0xF (36-bit build). This macro is
4512 used in assembly code, so it must not contain typecasts or
4513 integer size suffixes (e.g. "ULL").
4515 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
4516 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
4517 used in assembly code, so it must not contain typecasts or
4518 integer size suffixes (e.g. "ULL").
4520 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
4521 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
4522 forced to a value that ensures that CCSR is not relocated.
4524 - Floppy Disk Support:
4525 CONFIG_SYS_FDC_DRIVE_NUMBER
4527 the default drive number (default value 0)
4529 CONFIG_SYS_ISA_IO_STRIDE
4531 defines the spacing between FDC chipset registers
4534 CONFIG_SYS_ISA_IO_OFFSET
4536 defines the offset of register from address. It
4537 depends on which part of the data bus is connected to
4538 the FDC chipset. (default value 0)
4540 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
4541 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
4544 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
4545 fdc_hw_init() is called at the beginning of the FDC
4546 setup. fdc_hw_init() must be provided by the board
4547 source code. It is used to make hardware dependant
4551 Most IDE controllers were designed to be connected with PCI
4552 interface. Only few of them were designed for AHB interface.
4553 When software is doing ATA command and data transfer to
4554 IDE devices through IDE-AHB controller, some additional
4555 registers accessing to these kind of IDE-AHB controller
4558 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
4559 DO NOT CHANGE unless you know exactly what you're
4560 doing! (11-4) [MPC8xx/82xx systems only]
4562 - CONFIG_SYS_INIT_RAM_ADDR:
4564 Start address of memory area that can be used for
4565 initial data and stack; please note that this must be
4566 writable memory that is working WITHOUT special
4567 initialization, i. e. you CANNOT use normal RAM which
4568 will become available only after programming the
4569 memory controller and running certain initialization
4572 U-Boot uses the following memory types:
4573 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4574 - MPC824X: data cache
4575 - PPC4xx: data cache
4577 - CONFIG_SYS_GBL_DATA_OFFSET:
4579 Offset of the initial data structure in the memory
4580 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4581 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4582 data is located at the end of the available space
4583 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4584 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4585 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4586 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4589 On the MPC824X (or other systems that use the data
4590 cache for initial memory) the address chosen for
4591 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4592 point to an otherwise UNUSED address space between
4593 the top of RAM and the start of the PCI space.
4595 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4597 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4599 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4601 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4603 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4605 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4607 - CONFIG_SYS_OR_TIMING_SDRAM:
4610 - CONFIG_SYS_MAMR_PTA:
4611 periodic timer for refresh
4613 - CONFIG_SYS_DER: Debug Event Register (37-47)
4615 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4616 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4617 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4618 CONFIG_SYS_BR1_PRELIM:
4619 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4621 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4622 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4623 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4624 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4626 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4627 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4628 Machine Mode Register and Memory Periodic Timer
4629 Prescaler definitions (SDRAM timing)
4631 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4632 enable I2C microcode relocation patch (MPC8xx);
4633 define relocation offset in DPRAM [DSP2]
4635 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4636 enable SMC microcode relocation patch (MPC8xx);
4637 define relocation offset in DPRAM [SMC1]
4639 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4640 enable SPI microcode relocation patch (MPC8xx);
4641 define relocation offset in DPRAM [SCC4]
4643 - CONFIG_SYS_USE_OSCCLK:
4644 Use OSCM clock mode on MBX8xx board. Be careful,
4645 wrong setting might damage your board. Read
4646 doc/README.MBX before setting this variable!
4648 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4649 Offset of the bootmode word in DPRAM used by post
4650 (Power On Self Tests). This definition overrides
4651 #define'd default value in commproc.h resp.
4654 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4655 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4656 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4657 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4658 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4659 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4660 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4661 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4662 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4664 - CONFIG_PCI_DISABLE_PCIE:
4665 Disable PCI-Express on systems where it is supported but not
4668 - CONFIG_PCI_ENUM_ONLY
4669 Only scan through and get the devices on the busses.
4670 Don't do any setup work, presumably because someone or
4671 something has already done it, and we don't need to do it
4672 a second time. Useful for platforms that are pre-booted
4673 by coreboot or similar.
4675 - CONFIG_PCI_INDIRECT_BRIDGE:
4676 Enable support for indirect PCI bridges.
4679 Chip has SRIO or not
4682 Board has SRIO 1 port available
4685 Board has SRIO 2 port available
4687 - CONFIG_SRIO_PCIE_BOOT_MASTER
4688 Board can support master function for Boot from SRIO and PCIE
4690 - CONFIG_SYS_SRIOn_MEM_VIRT:
4691 Virtual Address of SRIO port 'n' memory region
4693 - CONFIG_SYS_SRIOn_MEM_PHYS:
4694 Physical Address of SRIO port 'n' memory region
4696 - CONFIG_SYS_SRIOn_MEM_SIZE:
4697 Size of SRIO port 'n' memory region
4699 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4700 Defined to tell the NAND controller that the NAND chip is using
4702 Not all NAND drivers use this symbol.
4703 Example of drivers that use it:
4704 - drivers/mtd/nand/ndfc.c
4705 - drivers/mtd/nand/mxc_nand.c
4707 - CONFIG_SYS_NDFC_EBC0_CFG
4708 Sets the EBC0_CFG register for the NDFC. If not defined
4709 a default value will be used.
4712 Get DDR timing information from an I2C EEPROM. Common
4713 with pluggable memory modules such as SODIMMs
4716 I2C address of the SPD EEPROM
4718 - CONFIG_SYS_SPD_BUS_NUM
4719 If SPD EEPROM is on an I2C bus other than the first
4720 one, specify here. Note that the value must resolve
4721 to something your driver can deal with.
4723 - CONFIG_SYS_DDR_RAW_TIMING
4724 Get DDR timing information from other than SPD. Common with
4725 soldered DDR chips onboard without SPD. DDR raw timing
4726 parameters are extracted from datasheet and hard-coded into
4727 header files or board specific files.
4729 - CONFIG_FSL_DDR_INTERACTIVE
4730 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4732 - CONFIG_SYS_83XX_DDR_USES_CS0
4733 Only for 83xx systems. If specified, then DDR should
4734 be configured using CS0 and CS1 instead of CS2 and CS3.
4736 - CONFIG_ETHER_ON_FEC[12]
4737 Define to enable FEC[12] on a 8xx series processor.
4739 - CONFIG_FEC[12]_PHY
4740 Define to the hardcoded PHY address which corresponds
4741 to the given FEC; i. e.
4742 #define CONFIG_FEC1_PHY 4
4743 means that the PHY with address 4 is connected to FEC1
4745 When set to -1, means to probe for first available.
4747 - CONFIG_FEC[12]_PHY_NORXERR
4748 The PHY does not have a RXERR line (RMII only).
4749 (so program the FEC to ignore it).
4752 Enable RMII mode for all FECs.
4753 Note that this is a global option, we can't
4754 have one FEC in standard MII mode and another in RMII mode.
4756 - CONFIG_CRC32_VERIFY
4757 Add a verify option to the crc32 command.
4760 => crc32 -v <address> <count> <crc32>
4762 Where address/count indicate a memory area
4763 and crc32 is the correct crc32 which the
4767 Add the "loopw" memory command. This only takes effect if
4768 the memory commands are activated globally (CONFIG_CMD_MEM).
4771 Add the "mdc" and "mwc" memory commands. These are cyclic
4776 This command will print 4 bytes (10,11,12,13) each 500 ms.
4778 => mwc.l 100 12345678 10
4779 This command will write 12345678 to address 100 all 10 ms.
4781 This only takes effect if the memory commands are activated
4782 globally (CONFIG_CMD_MEM).
4784 - CONFIG_SKIP_LOWLEVEL_INIT
4785 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4786 low level initializations (like setting up the memory
4787 controller) are omitted and/or U-Boot does not
4788 relocate itself into RAM.
4790 Normally this variable MUST NOT be defined. The only
4791 exception is when U-Boot is loaded (to RAM) by some
4792 other boot loader or by a debugger which performs
4793 these initializations itself.
4796 Modifies the behaviour of start.S when compiling a loader
4797 that is executed before the actual U-Boot. E.g. when
4798 compiling a NAND SPL.
4801 Modifies the behaviour of start.S when compiling a loader
4802 that is executed after the SPL and before the actual U-Boot.
4803 It is loaded by the SPL.
4805 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4806 Only for 85xx systems. If this variable is specified, the section
4807 .resetvec is not kept and the section .bootpg is placed in the
4808 previous 4k of the .text section.
4810 - CONFIG_ARCH_MAP_SYSMEM
4811 Generally U-Boot (and in particular the md command) uses
4812 effective address. It is therefore not necessary to regard
4813 U-Boot address as virtual addresses that need to be translated
4814 to physical addresses. However, sandbox requires this, since
4815 it maintains its own little RAM buffer which contains all
4816 addressable memory. This option causes some memory accesses
4817 to be mapped through map_sysmem() / unmap_sysmem().
4819 - CONFIG_USE_ARCH_MEMCPY
4820 CONFIG_USE_ARCH_MEMSET
4821 If these options are used a optimized version of memcpy/memset will
4822 be used if available. These functions may be faster under some
4823 conditions but may increase the binary size.
4825 - CONFIG_X86_RESET_VECTOR
4826 If defined, the x86 reset vector code is included. This is not
4827 needed when U-Boot is running from Coreboot.
4830 Defines the MPU clock speed (in MHz).
4832 NOTE : currently only supported on AM335x platforms.
4834 - CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
4835 Enables the RTC32K OSC on AM33xx based plattforms
4837 - CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
4838 Option to disable subpage write in NAND driver
4839 driver that uses this:
4840 drivers/mtd/nand/davinci_nand.c
4842 Freescale QE/FMAN Firmware Support:
4843 -----------------------------------
4845 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4846 loading of "firmware", which is encoded in the QE firmware binary format.
4847 This firmware often needs to be loaded during U-Boot booting, so macros
4848 are used to identify the storage device (NOR flash, SPI, etc) and the address
4851 - CONFIG_SYS_FMAN_FW_ADDR
4852 The address in the storage device where the FMAN microcode is located. The
4853 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4856 - CONFIG_SYS_QE_FW_ADDR
4857 The address in the storage device where the QE microcode is located. The
4858 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4861 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4862 The maximum possible size of the firmware. The firmware binary format
4863 has a field that specifies the actual size of the firmware, but it
4864 might not be possible to read any part of the firmware unless some
4865 local storage is allocated to hold the entire firmware first.
4867 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4868 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4869 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4870 virtual address in NOR flash.
4872 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4873 Specifies that QE/FMAN firmware is located in NAND flash.
4874 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4876 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4877 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4878 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4880 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4881 Specifies that QE/FMAN firmware is located on the primary SPI
4882 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4884 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4885 Specifies that QE/FMAN firmware is located in the remote (master)
4886 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4887 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4888 window->master inbound window->master LAW->the ucode address in
4889 master's memory space.
4891 Freescale Layerscape Management Complex Firmware Support:
4892 ---------------------------------------------------------
4893 The Freescale Layerscape Management Complex (MC) supports the loading of
4895 This firmware often needs to be loaded during U-Boot booting, so macros
4896 are used to identify the storage device (NOR flash, SPI, etc) and the address
4899 - CONFIG_FSL_MC_ENET
4900 Enable the MC driver for Layerscape SoCs.
4902 - CONFIG_SYS_LS_MC_FW_ADDR
4903 The address in the storage device where the firmware is located. The
4904 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro
4907 - CONFIG_SYS_LS_MC_FW_LENGTH
4908 The maximum possible size of the firmware. The firmware binary format
4909 has a field that specifies the actual size of the firmware, but it
4910 might not be possible to read any part of the firmware unless some
4911 local storage is allocated to hold the entire firmware first.
4913 - CONFIG_SYS_LS_MC_FW_IN_NOR
4914 Specifies that MC firmware is located in NOR flash, mapped as
4915 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the
4916 virtual address in NOR flash.
4918 Building the Software:
4919 ======================
4921 Building U-Boot has been tested in several native build environments
4922 and in many different cross environments. Of course we cannot support
4923 all possibly existing versions of cross development tools in all
4924 (potentially obsolete) versions. In case of tool chain problems we
4925 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4926 which is extensively used to build and test U-Boot.
4928 If you are not using a native environment, it is assumed that you
4929 have GNU cross compiling tools available in your path. In this case,
4930 you must set the environment variable CROSS_COMPILE in your shell.
4931 Note that no changes to the Makefile or any other source files are
4932 necessary. For example using the ELDK on a 4xx CPU, please enter:
4934 $ CROSS_COMPILE=ppc_4xx-
4935 $ export CROSS_COMPILE
4937 Note: If you wish to generate Windows versions of the utilities in
4938 the tools directory you can use the MinGW toolchain
4939 (http://www.mingw.org). Set your HOST tools to the MinGW
4940 toolchain and execute 'make tools'. For example:
4942 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4944 Binaries such as tools/mkimage.exe will be created which can
4945 be executed on computers running Windows.
4947 U-Boot is intended to be simple to build. After installing the
4948 sources you must configure U-Boot for one specific board type. This
4953 where "NAME_defconfig" is the name of one of the existing configu-
4954 rations; see boards.cfg for supported names.
4956 Note: for some board special configuration names may exist; check if
4957 additional information is available from the board vendor; for
4958 instance, the TQM823L systems are available without (standard)
4959 or with LCD support. You can select such additional "features"
4960 when choosing the configuration, i. e.
4962 make TQM823L_defconfig
4963 - will configure for a plain TQM823L, i. e. no LCD support
4965 make TQM823L_LCD_defconfig
4966 - will configure for a TQM823L with U-Boot console on LCD
4971 Finally, type "make all", and you should get some working U-Boot
4972 images ready for download to / installation on your system:
4974 - "u-boot.bin" is a raw binary image
4975 - "u-boot" is an image in ELF binary format
4976 - "u-boot.srec" is in Motorola S-Record format
4978 By default the build is performed locally and the objects are saved
4979 in the source directory. One of the two methods can be used to change
4980 this behavior and build U-Boot to some external directory:
4982 1. Add O= to the make command line invocations:
4984 make O=/tmp/build distclean
4985 make O=/tmp/build NAME_defconfig
4986 make O=/tmp/build all
4988 2. Set environment variable BUILD_DIR to point to the desired location:
4990 export BUILD_DIR=/tmp/build
4995 Note that the command line "O=" setting overrides the BUILD_DIR environment
4999 Please be aware that the Makefiles assume you are using GNU make, so
5000 for instance on NetBSD you might need to use "gmake" instead of
5004 If the system board that you have is not listed, then you will need
5005 to port U-Boot to your hardware platform. To do this, follow these
5008 1. Add a new configuration option for your board to the toplevel
5009 "boards.cfg" file, using the existing entries as examples.
5010 Follow the instructions there to keep the boards in order.
5011 2. Create a new directory to hold your board specific code. Add any
5012 files you need. In your board directory, you will need at least
5013 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
5014 3. Create a new configuration file "include/configs/<board>.h" for
5016 3. If you're porting U-Boot to a new CPU, then also create a new
5017 directory to hold your CPU specific code. Add any files you need.
5018 4. Run "make <board>_defconfig" with your new name.
5019 5. Type "make", and you should get a working "u-boot.srec" file
5020 to be installed on your target system.
5021 6. Debug and solve any problems that might arise.
5022 [Of course, this last step is much harder than it sounds.]
5025 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
5026 ==============================================================
5028 If you have modified U-Boot sources (for instance added a new board
5029 or support for new devices, a new CPU, etc.) you are expected to
5030 provide feedback to the other developers. The feedback normally takes
5031 the form of a "patch", i. e. a context diff against a certain (latest
5032 official or latest in the git repository) version of U-Boot sources.
5034 But before you submit such a patch, please verify that your modifi-
5035 cation did not break existing code. At least make sure that *ALL* of
5036 the supported boards compile WITHOUT ANY compiler warnings. To do so,
5037 just run the "MAKEALL" script, which will configure and build U-Boot
5038 for ALL supported system. Be warned, this will take a while. You can
5039 select which (cross) compiler to use by passing a `CROSS_COMPILE'
5040 environment variable to the script, i. e. to use the ELDK cross tools
5043 CROSS_COMPILE=ppc_8xx- MAKEALL
5045 or to build on a native PowerPC system you can type
5047 CROSS_COMPILE=' ' MAKEALL
5049 When using the MAKEALL script, the default behaviour is to build
5050 U-Boot in the source directory. This location can be changed by
5051 setting the BUILD_DIR environment variable. Also, for each target
5052 built, the MAKEALL script saves two log files (<target>.ERR and
5053 <target>.MAKEALL) in the <source dir>/LOG directory. This default
5054 location can be changed by setting the MAKEALL_LOGDIR environment
5055 variable. For example:
5057 export BUILD_DIR=/tmp/build
5058 export MAKEALL_LOGDIR=/tmp/log
5059 CROSS_COMPILE=ppc_8xx- MAKEALL
5061 With the above settings build objects are saved in the /tmp/build,
5062 log files are saved in the /tmp/log and the source tree remains clean
5063 during the whole build process.
5066 See also "U-Boot Porting Guide" below.
5069 Monitor Commands - Overview:
5070 ============================
5072 go - start application at address 'addr'
5073 run - run commands in an environment variable
5074 bootm - boot application image from memory
5075 bootp - boot image via network using BootP/TFTP protocol
5076 bootz - boot zImage from memory
5077 tftpboot- boot image via network using TFTP protocol
5078 and env variables "ipaddr" and "serverip"
5079 (and eventually "gatewayip")
5080 tftpput - upload a file via network using TFTP protocol
5081 rarpboot- boot image via network using RARP/TFTP protocol
5082 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
5083 loads - load S-Record file over serial line
5084 loadb - load binary file over serial line (kermit mode)
5086 mm - memory modify (auto-incrementing)
5087 nm - memory modify (constant address)
5088 mw - memory write (fill)
5090 cmp - memory compare
5091 crc32 - checksum calculation
5092 i2c - I2C sub-system
5093 sspi - SPI utility commands
5094 base - print or set address offset
5095 printenv- print environment variables
5096 setenv - set environment variables
5097 saveenv - save environment variables to persistent storage
5098 protect - enable or disable FLASH write protection
5099 erase - erase FLASH memory
5100 flinfo - print FLASH memory information
5101 nand - NAND memory operations (see doc/README.nand)
5102 bdinfo - print Board Info structure
5103 iminfo - print header information for application image
5104 coninfo - print console devices and informations
5105 ide - IDE sub-system
5106 loop - infinite loop on address range
5107 loopw - infinite write loop on address range
5108 mtest - simple RAM test
5109 icache - enable or disable instruction cache
5110 dcache - enable or disable data cache
5111 reset - Perform RESET of the CPU
5112 echo - echo args to console
5113 version - print monitor version
5114 help - print online help
5115 ? - alias for 'help'
5118 Monitor Commands - Detailed Description:
5119 ========================================
5123 For now: just type "help <command>".
5126 Environment Variables:
5127 ======================
5129 U-Boot supports user configuration using Environment Variables which
5130 can be made persistent by saving to Flash memory.
5132 Environment Variables are set using "setenv", printed using
5133 "printenv", and saved to Flash using "saveenv". Using "setenv"
5134 without a value can be used to delete a variable from the
5135 environment. As long as you don't save the environment you are
5136 working with an in-memory copy. In case the Flash area containing the
5137 environment is erased by accident, a default environment is provided.
5139 Some configuration options can be set using Environment Variables.
5141 List of environment variables (most likely not complete):
5143 baudrate - see CONFIG_BAUDRATE
5145 bootdelay - see CONFIG_BOOTDELAY
5147 bootcmd - see CONFIG_BOOTCOMMAND
5149 bootargs - Boot arguments when booting an RTOS image
5151 bootfile - Name of the image to load with TFTP
5153 bootm_low - Memory range available for image processing in the bootm
5154 command can be restricted. This variable is given as
5155 a hexadecimal number and defines lowest address allowed
5156 for use by the bootm command. See also "bootm_size"
5157 environment variable. Address defined by "bootm_low" is
5158 also the base of the initial memory mapping for the Linux
5159 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
5162 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
5163 This variable is given as a hexadecimal number and it
5164 defines the size of the memory region starting at base
5165 address bootm_low that is accessible by the Linux kernel
5166 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
5167 as the default value if it is defined, and bootm_size is
5170 bootm_size - Memory range available for image processing in the bootm
5171 command can be restricted. This variable is given as
5172 a hexadecimal number and defines the size of the region
5173 allowed for use by the bootm command. See also "bootm_low"
5174 environment variable.
5176 updatefile - Location of the software update file on a TFTP server, used
5177 by the automatic software update feature. Please refer to
5178 documentation in doc/README.update for more details.
5180 autoload - if set to "no" (any string beginning with 'n'),
5181 "bootp" will just load perform a lookup of the
5182 configuration from the BOOTP server, but not try to
5183 load any image using TFTP
5185 autostart - if set to "yes", an image loaded using the "bootp",
5186 "rarpboot", "tftpboot" or "diskboot" commands will
5187 be automatically started (by internally calling
5190 If set to "no", a standalone image passed to the
5191 "bootm" command will be copied to the load address
5192 (and eventually uncompressed), but NOT be started.
5193 This can be used to load and uncompress arbitrary
5196 fdt_high - if set this restricts the maximum address that the
5197 flattened device tree will be copied into upon boot.
5198 For example, if you have a system with 1 GB memory
5199 at physical address 0x10000000, while Linux kernel
5200 only recognizes the first 704 MB as low memory, you
5201 may need to set fdt_high as 0x3C000000 to have the
5202 device tree blob be copied to the maximum address
5203 of the 704 MB low memory, so that Linux kernel can
5204 access it during the boot procedure.
5206 If this is set to the special value 0xFFFFFFFF then
5207 the fdt will not be copied at all on boot. For this
5208 to work it must reside in writable memory, have
5209 sufficient padding on the end of it for u-boot to
5210 add the information it needs into it, and the memory
5211 must be accessible by the kernel.
5213 fdtcontroladdr- if set this is the address of the control flattened
5214 device tree used by U-Boot when CONFIG_OF_CONTROL is
5217 i2cfast - (PPC405GP|PPC405EP only)
5218 if set to 'y' configures Linux I2C driver for fast
5219 mode (400kHZ). This environment variable is used in
5220 initialization code. So, for changes to be effective
5221 it must be saved and board must be reset.
5223 initrd_high - restrict positioning of initrd images:
5224 If this variable is not set, initrd images will be
5225 copied to the highest possible address in RAM; this
5226 is usually what you want since it allows for
5227 maximum initrd size. If for some reason you want to
5228 make sure that the initrd image is loaded below the
5229 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
5230 variable to a value of "no" or "off" or "0".
5231 Alternatively, you can set it to a maximum upper
5232 address to use (U-Boot will still check that it
5233 does not overwrite the U-Boot stack and data).
5235 For instance, when you have a system with 16 MB
5236 RAM, and want to reserve 4 MB from use by Linux,
5237 you can do this by adding "mem=12M" to the value of
5238 the "bootargs" variable. However, now you must make
5239 sure that the initrd image is placed in the first
5240 12 MB as well - this can be done with
5242 setenv initrd_high 00c00000
5244 If you set initrd_high to 0xFFFFFFFF, this is an
5245 indication to U-Boot that all addresses are legal
5246 for the Linux kernel, including addresses in flash
5247 memory. In this case U-Boot will NOT COPY the
5248 ramdisk at all. This may be useful to reduce the
5249 boot time on your system, but requires that this
5250 feature is supported by your Linux kernel.
5252 ipaddr - IP address; needed for tftpboot command
5254 loadaddr - Default load address for commands like "bootp",
5255 "rarpboot", "tftpboot", "loadb" or "diskboot"
5257 loads_echo - see CONFIG_LOADS_ECHO
5259 serverip - TFTP server IP address; needed for tftpboot command
5261 bootretry - see CONFIG_BOOT_RETRY_TIME
5263 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
5265 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
5267 ethprime - controls which interface is used first.
5269 ethact - controls which interface is currently active.
5270 For example you can do the following
5272 => setenv ethact FEC
5273 => ping 192.168.0.1 # traffic sent on FEC
5274 => setenv ethact SCC
5275 => ping 10.0.0.1 # traffic sent on SCC
5277 ethrotate - When set to "no" U-Boot does not go through all
5278 available network interfaces.
5279 It just stays at the currently selected interface.
5281 netretry - When set to "no" each network operation will
5282 either succeed or fail without retrying.
5283 When set to "once" the network operation will
5284 fail when all the available network interfaces
5285 are tried once without success.
5286 Useful on scripts which control the retry operation
5289 npe_ucode - set load address for the NPE microcode
5291 silent_linux - If set then linux will be told to boot silently, by
5292 changing the console to be empty. If "yes" it will be
5293 made silent. If "no" it will not be made silent. If
5294 unset, then it will be made silent if the U-Boot console
5297 tftpsrcport - If this is set, the value is used for TFTP's
5300 tftpdstport - If this is set, the value is used for TFTP's UDP
5301 destination port instead of the Well Know Port 69.
5303 tftpblocksize - Block size to use for TFTP transfers; if not set,
5304 we use the TFTP server's default block size
5306 tftptimeout - Retransmission timeout for TFTP packets (in milli-
5307 seconds, minimum value is 1000 = 1 second). Defines
5308 when a packet is considered to be lost so it has to
5309 be retransmitted. The default is 5000 = 5 seconds.
5310 Lowering this value may make downloads succeed
5311 faster in networks with high packet loss rates or
5312 with unreliable TFTP servers.
5314 vlan - When set to a value < 4095 the traffic over
5315 Ethernet is encapsulated/received over 802.1q
5318 The following image location variables contain the location of images
5319 used in booting. The "Image" column gives the role of the image and is
5320 not an environment variable name. The other columns are environment
5321 variable names. "File Name" gives the name of the file on a TFTP
5322 server, "RAM Address" gives the location in RAM the image will be
5323 loaded to, and "Flash Location" gives the image's address in NOR
5324 flash or offset in NAND flash.
5326 *Note* - these variables don't have to be defined for all boards, some
5327 boards currenlty use other variables for these purposes, and some
5328 boards use these variables for other purposes.
5330 Image File Name RAM Address Flash Location
5331 ----- --------- ----------- --------------
5332 u-boot u-boot u-boot_addr_r u-boot_addr
5333 Linux kernel bootfile kernel_addr_r kernel_addr
5334 device tree blob fdtfile fdt_addr_r fdt_addr
5335 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
5337 The following environment variables may be used and automatically
5338 updated by the network boot commands ("bootp" and "rarpboot"),
5339 depending the information provided by your boot server:
5341 bootfile - see above
5342 dnsip - IP address of your Domain Name Server
5343 dnsip2 - IP address of your secondary Domain Name Server
5344 gatewayip - IP address of the Gateway (Router) to use
5345 hostname - Target hostname
5347 netmask - Subnet Mask
5348 rootpath - Pathname of the root filesystem on the NFS server
5349 serverip - see above
5352 There are two special Environment Variables:
5354 serial# - contains hardware identification information such
5355 as type string and/or serial number
5356 ethaddr - Ethernet address
5358 These variables can be set only once (usually during manufacturing of
5359 the board). U-Boot refuses to delete or overwrite these variables
5360 once they have been set once.
5363 Further special Environment Variables:
5365 ver - Contains the U-Boot version string as printed
5366 with the "version" command. This variable is
5367 readonly (see CONFIG_VERSION_VARIABLE).
5370 Please note that changes to some configuration parameters may take
5371 only effect after the next boot (yes, that's just like Windoze :-).
5374 Callback functions for environment variables:
5375 ---------------------------------------------
5377 For some environment variables, the behavior of u-boot needs to change
5378 when their values are changed. This functionailty allows functions to
5379 be associated with arbitrary variables. On creation, overwrite, or
5380 deletion, the callback will provide the opportunity for some side
5381 effect to happen or for the change to be rejected.
5383 The callbacks are named and associated with a function using the
5384 U_BOOT_ENV_CALLBACK macro in your board or driver code.
5386 These callbacks are associated with variables in one of two ways. The
5387 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
5388 in the board configuration to a string that defines a list of
5389 associations. The list must be in the following format:
5391 entry = variable_name[:callback_name]
5394 If the callback name is not specified, then the callback is deleted.
5395 Spaces are also allowed anywhere in the list.
5397 Callbacks can also be associated by defining the ".callbacks" variable
5398 with the same list format above. Any association in ".callbacks" will
5399 override any association in the static list. You can define
5400 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
5401 ".callbacks" envirnoment variable in the default or embedded environment.
5404 Command Line Parsing:
5405 =====================
5407 There are two different command line parsers available with U-Boot:
5408 the old "simple" one, and the much more powerful "hush" shell:
5410 Old, simple command line parser:
5411 --------------------------------
5413 - supports environment variables (through setenv / saveenv commands)
5414 - several commands on one line, separated by ';'
5415 - variable substitution using "... ${name} ..." syntax
5416 - special characters ('$', ';') can be escaped by prefixing with '\',
5418 setenv bootcmd bootm \${address}
5419 - You can also escape text by enclosing in single apostrophes, for example:
5420 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
5425 - similar to Bourne shell, with control structures like
5426 if...then...else...fi, for...do...done; while...do...done,
5427 until...do...done, ...
5428 - supports environment ("global") variables (through setenv / saveenv
5429 commands) and local shell variables (through standard shell syntax
5430 "name=value"); only environment variables can be used with "run"
5436 (1) If a command line (or an environment variable executed by a "run"
5437 command) contains several commands separated by semicolon, and
5438 one of these commands fails, then the remaining commands will be
5441 (2) If you execute several variables with one call to run (i. e.
5442 calling run with a list of variables as arguments), any failing
5443 command will cause "run" to terminate, i. e. the remaining
5444 variables are not executed.
5446 Note for Redundant Ethernet Interfaces:
5447 =======================================
5449 Some boards come with redundant Ethernet interfaces; U-Boot supports
5450 such configurations and is capable of automatic selection of a
5451 "working" interface when needed. MAC assignment works as follows:
5453 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
5454 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
5455 "eth1addr" (=>eth1), "eth2addr", ...
5457 If the network interface stores some valid MAC address (for instance
5458 in SROM), this is used as default address if there is NO correspon-
5459 ding setting in the environment; if the corresponding environment
5460 variable is set, this overrides the settings in the card; that means:
5462 o If the SROM has a valid MAC address, and there is no address in the
5463 environment, the SROM's address is used.
5465 o If there is no valid address in the SROM, and a definition in the
5466 environment exists, then the value from the environment variable is
5469 o If both the SROM and the environment contain a MAC address, and
5470 both addresses are the same, this MAC address is used.
5472 o If both the SROM and the environment contain a MAC address, and the
5473 addresses differ, the value from the environment is used and a
5476 o If neither SROM nor the environment contain a MAC address, an error
5479 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
5480 will be programmed into hardware as part of the initialization process. This
5481 may be skipped by setting the appropriate 'ethmacskip' environment variable.
5482 The naming convention is as follows:
5483 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
5488 U-Boot is capable of booting (and performing other auxiliary operations on)
5489 images in two formats:
5491 New uImage format (FIT)
5492 -----------------------
5494 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
5495 to Flattened Device Tree). It allows the use of images with multiple
5496 components (several kernels, ramdisks, etc.), with contents protected by
5497 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
5503 Old image format is based on binary files which can be basically anything,
5504 preceded by a special header; see the definitions in include/image.h for
5505 details; basically, the header defines the following image properties:
5507 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
5508 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
5509 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
5510 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
5512 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
5513 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
5514 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
5515 * Compression Type (uncompressed, gzip, bzip2)
5521 The header is marked by a special Magic Number, and both the header
5522 and the data portions of the image are secured against corruption by
5529 Although U-Boot should support any OS or standalone application
5530 easily, the main focus has always been on Linux during the design of
5533 U-Boot includes many features that so far have been part of some
5534 special "boot loader" code within the Linux kernel. Also, any
5535 "initrd" images to be used are no longer part of one big Linux image;
5536 instead, kernel and "initrd" are separate images. This implementation
5537 serves several purposes:
5539 - the same features can be used for other OS or standalone
5540 applications (for instance: using compressed images to reduce the
5541 Flash memory footprint)
5543 - it becomes much easier to port new Linux kernel versions because
5544 lots of low-level, hardware dependent stuff are done by U-Boot
5546 - the same Linux kernel image can now be used with different "initrd"
5547 images; of course this also means that different kernel images can
5548 be run with the same "initrd". This makes testing easier (you don't
5549 have to build a new "zImage.initrd" Linux image when you just
5550 change a file in your "initrd"). Also, a field-upgrade of the
5551 software is easier now.
5557 Porting Linux to U-Boot based systems:
5558 ---------------------------------------
5560 U-Boot cannot save you from doing all the necessary modifications to
5561 configure the Linux device drivers for use with your target hardware
5562 (no, we don't intend to provide a full virtual machine interface to
5565 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
5567 Just make sure your machine specific header file (for instance
5568 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
5569 Information structure as we define in include/asm-<arch>/u-boot.h,
5570 and make sure that your definition of IMAP_ADDR uses the same value
5571 as your U-Boot configuration in CONFIG_SYS_IMMR.
5573 Note that U-Boot now has a driver model, a unified model for drivers.
5574 If you are adding a new driver, plumb it into driver model. If there
5575 is no uclass available, you are encouraged to create one. See
5579 Configuring the Linux kernel:
5580 -----------------------------
5582 No specific requirements for U-Boot. Make sure you have some root
5583 device (initial ramdisk, NFS) for your target system.
5586 Building a Linux Image:
5587 -----------------------
5589 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
5590 not used. If you use recent kernel source, a new build target
5591 "uImage" will exist which automatically builds an image usable by
5592 U-Boot. Most older kernels also have support for a "pImage" target,
5593 which was introduced for our predecessor project PPCBoot and uses a
5594 100% compatible format.
5598 make TQM850L_defconfig
5603 The "uImage" build target uses a special tool (in 'tools/mkimage') to
5604 encapsulate a compressed Linux kernel image with header information,
5605 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
5607 * build a standard "vmlinux" kernel image (in ELF binary format):
5609 * convert the kernel into a raw binary image:
5611 ${CROSS_COMPILE}-objcopy -O binary \
5612 -R .note -R .comment \
5613 -S vmlinux linux.bin
5615 * compress the binary image:
5619 * package compressed binary image for U-Boot:
5621 mkimage -A ppc -O linux -T kernel -C gzip \
5622 -a 0 -e 0 -n "Linux Kernel Image" \
5623 -d linux.bin.gz uImage
5626 The "mkimage" tool can also be used to create ramdisk images for use
5627 with U-Boot, either separated from the Linux kernel image, or
5628 combined into one file. "mkimage" encapsulates the images with a 64
5629 byte header containing information about target architecture,
5630 operating system, image type, compression method, entry points, time
5631 stamp, CRC32 checksums, etc.
5633 "mkimage" can be called in two ways: to verify existing images and
5634 print the header information, or to build new images.
5636 In the first form (with "-l" option) mkimage lists the information
5637 contained in the header of an existing U-Boot image; this includes
5638 checksum verification:
5640 tools/mkimage -l image
5641 -l ==> list image header information
5643 The second form (with "-d" option) is used to build a U-Boot image
5644 from a "data file" which is used as image payload:
5646 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5647 -n name -d data_file image
5648 -A ==> set architecture to 'arch'
5649 -O ==> set operating system to 'os'
5650 -T ==> set image type to 'type'
5651 -C ==> set compression type 'comp'
5652 -a ==> set load address to 'addr' (hex)
5653 -e ==> set entry point to 'ep' (hex)
5654 -n ==> set image name to 'name'
5655 -d ==> use image data from 'datafile'
5657 Right now, all Linux kernels for PowerPC systems use the same load
5658 address (0x00000000), but the entry point address depends on the
5661 - 2.2.x kernels have the entry point at 0x0000000C,
5662 - 2.3.x and later kernels have the entry point at 0x00000000.
5664 So a typical call to build a U-Boot image would read:
5666 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5667 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5668 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5669 > examples/uImage.TQM850L
5670 Image Name: 2.4.4 kernel for TQM850L
5671 Created: Wed Jul 19 02:34:59 2000
5672 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5673 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5674 Load Address: 0x00000000
5675 Entry Point: 0x00000000
5677 To verify the contents of the image (or check for corruption):
5679 -> tools/mkimage -l examples/uImage.TQM850L
5680 Image Name: 2.4.4 kernel for TQM850L
5681 Created: Wed Jul 19 02:34:59 2000
5682 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5683 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5684 Load Address: 0x00000000
5685 Entry Point: 0x00000000
5687 NOTE: for embedded systems where boot time is critical you can trade
5688 speed for memory and install an UNCOMPRESSED image instead: this
5689 needs more space in Flash, but boots much faster since it does not
5690 need to be uncompressed:
5692 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5693 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5694 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5695 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5696 > examples/uImage.TQM850L-uncompressed
5697 Image Name: 2.4.4 kernel for TQM850L
5698 Created: Wed Jul 19 02:34:59 2000
5699 Image Type: PowerPC Linux Kernel Image (uncompressed)
5700 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5701 Load Address: 0x00000000
5702 Entry Point: 0x00000000
5705 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5706 when your kernel is intended to use an initial ramdisk:
5708 -> tools/mkimage -n 'Simple Ramdisk Image' \
5709 > -A ppc -O linux -T ramdisk -C gzip \
5710 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5711 Image Name: Simple Ramdisk Image
5712 Created: Wed Jan 12 14:01:50 2000
5713 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5714 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5715 Load Address: 0x00000000
5716 Entry Point: 0x00000000
5718 The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
5719 option performs the converse operation of the mkimage's second form (the "-d"
5720 option). Given an image built by mkimage, the dumpimage extracts a "data file"
5723 tools/dumpimage -i image -p position data_file
5724 -i ==> extract from the 'image' a specific 'data_file', \
5725 indexed by 'position'
5728 Installing a Linux Image:
5729 -------------------------
5731 To downloading a U-Boot image over the serial (console) interface,
5732 you must convert the image to S-Record format:
5734 objcopy -I binary -O srec examples/image examples/image.srec
5736 The 'objcopy' does not understand the information in the U-Boot
5737 image header, so the resulting S-Record file will be relative to
5738 address 0x00000000. To load it to a given address, you need to
5739 specify the target address as 'offset' parameter with the 'loads'
5742 Example: install the image to address 0x40100000 (which on the
5743 TQM8xxL is in the first Flash bank):
5745 => erase 40100000 401FFFFF
5751 ## Ready for S-Record download ...
5752 ~>examples/image.srec
5753 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5755 15989 15990 15991 15992
5756 [file transfer complete]
5758 ## Start Addr = 0x00000000
5761 You can check the success of the download using the 'iminfo' command;
5762 this includes a checksum verification so you can be sure no data
5763 corruption happened:
5767 ## Checking Image at 40100000 ...
5768 Image Name: 2.2.13 for initrd on TQM850L
5769 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5770 Data Size: 335725 Bytes = 327 kB = 0 MB
5771 Load Address: 00000000
5772 Entry Point: 0000000c
5773 Verifying Checksum ... OK
5779 The "bootm" command is used to boot an application that is stored in
5780 memory (RAM or Flash). In case of a Linux kernel image, the contents
5781 of the "bootargs" environment variable is passed to the kernel as
5782 parameters. You can check and modify this variable using the
5783 "printenv" and "setenv" commands:
5786 => printenv bootargs
5787 bootargs=root=/dev/ram
5789 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5791 => printenv bootargs
5792 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5795 ## Booting Linux kernel at 40020000 ...
5796 Image Name: 2.2.13 for NFS on TQM850L
5797 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5798 Data Size: 381681 Bytes = 372 kB = 0 MB
5799 Load Address: 00000000
5800 Entry Point: 0000000c
5801 Verifying Checksum ... OK
5802 Uncompressing Kernel Image ... OK
5803 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
5804 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5805 time_init: decrementer frequency = 187500000/60
5806 Calibrating delay loop... 49.77 BogoMIPS
5807 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5810 If you want to boot a Linux kernel with initial RAM disk, you pass
5811 the memory addresses of both the kernel and the initrd image (PPBCOOT
5812 format!) to the "bootm" command:
5814 => imi 40100000 40200000
5816 ## Checking Image at 40100000 ...
5817 Image Name: 2.2.13 for initrd on TQM850L
5818 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5819 Data Size: 335725 Bytes = 327 kB = 0 MB
5820 Load Address: 00000000
5821 Entry Point: 0000000c
5822 Verifying Checksum ... OK
5824 ## Checking Image at 40200000 ...
5825 Image Name: Simple Ramdisk Image
5826 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5827 Data Size: 566530 Bytes = 553 kB = 0 MB
5828 Load Address: 00000000
5829 Entry Point: 00000000
5830 Verifying Checksum ... OK
5832 => bootm 40100000 40200000
5833 ## Booting Linux kernel at 40100000 ...
5834 Image Name: 2.2.13 for initrd on TQM850L
5835 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5836 Data Size: 335725 Bytes = 327 kB = 0 MB
5837 Load Address: 00000000
5838 Entry Point: 0000000c
5839 Verifying Checksum ... OK
5840 Uncompressing Kernel Image ... OK
5841 ## Loading RAMDisk Image at 40200000 ...
5842 Image Name: Simple Ramdisk Image
5843 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5844 Data Size: 566530 Bytes = 553 kB = 0 MB
5845 Load Address: 00000000
5846 Entry Point: 00000000
5847 Verifying Checksum ... OK
5848 Loading Ramdisk ... OK
5849 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
5850 Boot arguments: root=/dev/ram
5851 time_init: decrementer frequency = 187500000/60
5852 Calibrating delay loop... 49.77 BogoMIPS
5854 RAMDISK: Compressed image found at block 0
5855 VFS: Mounted root (ext2 filesystem).
5859 Boot Linux and pass a flat device tree:
5862 First, U-Boot must be compiled with the appropriate defines. See the section
5863 titled "Linux Kernel Interface" above for a more in depth explanation. The
5864 following is an example of how to start a kernel and pass an updated
5870 oft=oftrees/mpc8540ads.dtb
5871 => tftp $oftaddr $oft
5872 Speed: 1000, full duplex
5874 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5875 Filename 'oftrees/mpc8540ads.dtb'.
5876 Load address: 0x300000
5879 Bytes transferred = 4106 (100a hex)
5880 => tftp $loadaddr $bootfile
5881 Speed: 1000, full duplex
5883 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5885 Load address: 0x200000
5886 Loading:############
5888 Bytes transferred = 1029407 (fb51f hex)
5893 => bootm $loadaddr - $oftaddr
5894 ## Booting image at 00200000 ...
5895 Image Name: Linux-2.6.17-dirty
5896 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5897 Data Size: 1029343 Bytes = 1005.2 kB
5898 Load Address: 00000000
5899 Entry Point: 00000000
5900 Verifying Checksum ... OK
5901 Uncompressing Kernel Image ... OK
5902 Booting using flat device tree at 0x300000
5903 Using MPC85xx ADS machine description
5904 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5908 More About U-Boot Image Types:
5909 ------------------------------
5911 U-Boot supports the following image types:
5913 "Standalone Programs" are directly runnable in the environment
5914 provided by U-Boot; it is expected that (if they behave
5915 well) you can continue to work in U-Boot after return from
5916 the Standalone Program.
5917 "OS Kernel Images" are usually images of some Embedded OS which
5918 will take over control completely. Usually these programs
5919 will install their own set of exception handlers, device
5920 drivers, set up the MMU, etc. - this means, that you cannot
5921 expect to re-enter U-Boot except by resetting the CPU.
5922 "RAMDisk Images" are more or less just data blocks, and their
5923 parameters (address, size) are passed to an OS kernel that is
5925 "Multi-File Images" contain several images, typically an OS
5926 (Linux) kernel image and one or more data images like
5927 RAMDisks. This construct is useful for instance when you want
5928 to boot over the network using BOOTP etc., where the boot
5929 server provides just a single image file, but you want to get
5930 for instance an OS kernel and a RAMDisk image.
5932 "Multi-File Images" start with a list of image sizes, each
5933 image size (in bytes) specified by an "uint32_t" in network
5934 byte order. This list is terminated by an "(uint32_t)0".
5935 Immediately after the terminating 0 follow the images, one by
5936 one, all aligned on "uint32_t" boundaries (size rounded up to
5937 a multiple of 4 bytes).
5939 "Firmware Images" are binary images containing firmware (like
5940 U-Boot or FPGA images) which usually will be programmed to
5943 "Script files" are command sequences that will be executed by
5944 U-Boot's command interpreter; this feature is especially
5945 useful when you configure U-Boot to use a real shell (hush)
5946 as command interpreter.
5948 Booting the Linux zImage:
5949 -------------------------
5951 On some platforms, it's possible to boot Linux zImage. This is done
5952 using the "bootz" command. The syntax of "bootz" command is the same
5953 as the syntax of "bootm" command.
5955 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5956 kernel with raw initrd images. The syntax is slightly different, the
5957 address of the initrd must be augmented by it's size, in the following
5958 format: "<initrd addres>:<initrd size>".
5964 One of the features of U-Boot is that you can dynamically load and
5965 run "standalone" applications, which can use some resources of
5966 U-Boot like console I/O functions or interrupt services.
5968 Two simple examples are included with the sources:
5973 'examples/hello_world.c' contains a small "Hello World" Demo
5974 application; it is automatically compiled when you build U-Boot.
5975 It's configured to run at address 0x00040004, so you can play with it
5979 ## Ready for S-Record download ...
5980 ~>examples/hello_world.srec
5981 1 2 3 4 5 6 7 8 9 10 11 ...
5982 [file transfer complete]
5984 ## Start Addr = 0x00040004
5986 => go 40004 Hello World! This is a test.
5987 ## Starting application at 0x00040004 ...
5998 Hit any key to exit ...
6000 ## Application terminated, rc = 0x0
6002 Another example, which demonstrates how to register a CPM interrupt
6003 handler with the U-Boot code, can be found in 'examples/timer.c'.
6004 Here, a CPM timer is set up to generate an interrupt every second.
6005 The interrupt service routine is trivial, just printing a '.'
6006 character, but this is just a demo program. The application can be
6007 controlled by the following keys:
6009 ? - print current values og the CPM Timer registers
6010 b - enable interrupts and start timer
6011 e - stop timer and disable interrupts
6012 q - quit application
6015 ## Ready for S-Record download ...
6016 ~>examples/timer.srec
6017 1 2 3 4 5 6 7 8 9 10 11 ...
6018 [file transfer complete]
6020 ## Start Addr = 0x00040004
6023 ## Starting application at 0x00040004 ...
6026 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
6029 [q, b, e, ?] Set interval 1000000 us
6032 [q, b, e, ?] ........
6033 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
6036 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
6039 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
6042 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
6044 [q, b, e, ?] ...Stopping timer
6046 [q, b, e, ?] ## Application terminated, rc = 0x0
6052 Over time, many people have reported problems when trying to use the
6053 "minicom" terminal emulation program for serial download. I (wd)
6054 consider minicom to be broken, and recommend not to use it. Under
6055 Unix, I recommend to use C-Kermit for general purpose use (and
6056 especially for kermit binary protocol download ("loadb" command), and
6057 use "cu" for S-Record download ("loads" command). See
6058 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
6059 for help with kermit.
6062 Nevertheless, if you absolutely want to use it try adding this
6063 configuration to your "File transfer protocols" section:
6065 Name Program Name U/D FullScr IO-Red. Multi
6066 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
6067 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
6073 Starting at version 0.9.2, U-Boot supports NetBSD both as host
6074 (build U-Boot) and target system (boots NetBSD/mpc8xx).
6076 Building requires a cross environment; it is known to work on
6077 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
6078 need gmake since the Makefiles are not compatible with BSD make).
6079 Note that the cross-powerpc package does not install include files;
6080 attempting to build U-Boot will fail because <machine/ansi.h> is
6081 missing. This file has to be installed and patched manually:
6083 # cd /usr/pkg/cross/powerpc-netbsd/include
6085 # ln -s powerpc machine
6086 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
6087 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
6089 Native builds *don't* work due to incompatibilities between native
6090 and U-Boot include files.
6092 Booting assumes that (the first part of) the image booted is a
6093 stage-2 loader which in turn loads and then invokes the kernel
6094 proper. Loader sources will eventually appear in the NetBSD source
6095 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
6096 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
6099 Implementation Internals:
6100 =========================
6102 The following is not intended to be a complete description of every
6103 implementation detail. However, it should help to understand the
6104 inner workings of U-Boot and make it easier to port it to custom
6108 Initial Stack, Global Data:
6109 ---------------------------
6111 The implementation of U-Boot is complicated by the fact that U-Boot
6112 starts running out of ROM (flash memory), usually without access to
6113 system RAM (because the memory controller is not initialized yet).
6114 This means that we don't have writable Data or BSS segments, and BSS
6115 is not initialized as zero. To be able to get a C environment working
6116 at all, we have to allocate at least a minimal stack. Implementation
6117 options for this are defined and restricted by the CPU used: Some CPU
6118 models provide on-chip memory (like the IMMR area on MPC8xx and
6119 MPC826x processors), on others (parts of) the data cache can be
6120 locked as (mis-) used as memory, etc.
6122 Chris Hallinan posted a good summary of these issues to the
6123 U-Boot mailing list:
6125 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
6126 From: "Chris Hallinan" <clh@net1plus.com>
6127 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
6130 Correct me if I'm wrong, folks, but the way I understand it
6131 is this: Using DCACHE as initial RAM for Stack, etc, does not
6132 require any physical RAM backing up the cache. The cleverness
6133 is that the cache is being used as a temporary supply of
6134 necessary storage before the SDRAM controller is setup. It's
6135 beyond the scope of this list to explain the details, but you
6136 can see how this works by studying the cache architecture and
6137 operation in the architecture and processor-specific manuals.
6139 OCM is On Chip Memory, which I believe the 405GP has 4K. It
6140 is another option for the system designer to use as an
6141 initial stack/RAM area prior to SDRAM being available. Either
6142 option should work for you. Using CS 4 should be fine if your
6143 board designers haven't used it for something that would
6144 cause you grief during the initial boot! It is frequently not
6147 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
6148 with your processor/board/system design. The default value
6149 you will find in any recent u-boot distribution in
6150 walnut.h should work for you. I'd set it to a value larger
6151 than your SDRAM module. If you have a 64MB SDRAM module, set
6152 it above 400_0000. Just make sure your board has no resources
6153 that are supposed to respond to that address! That code in
6154 start.S has been around a while and should work as is when
6155 you get the config right.
6160 It is essential to remember this, since it has some impact on the C
6161 code for the initialization procedures:
6163 * Initialized global data (data segment) is read-only. Do not attempt
6166 * Do not use any uninitialized global data (or implicitely initialized
6167 as zero data - BSS segment) at all - this is undefined, initiali-
6168 zation is performed later (when relocating to RAM).
6170 * Stack space is very limited. Avoid big data buffers or things like
6173 Having only the stack as writable memory limits means we cannot use
6174 normal global data to share information beween the code. But it
6175 turned out that the implementation of U-Boot can be greatly
6176 simplified by making a global data structure (gd_t) available to all
6177 functions. We could pass a pointer to this data as argument to _all_
6178 functions, but this would bloat the code. Instead we use a feature of
6179 the GCC compiler (Global Register Variables) to share the data: we
6180 place a pointer (gd) to the global data into a register which we
6181 reserve for this purpose.
6183 When choosing a register for such a purpose we are restricted by the
6184 relevant (E)ABI specifications for the current architecture, and by
6185 GCC's implementation.
6187 For PowerPC, the following registers have specific use:
6189 R2: reserved for system use
6190 R3-R4: parameter passing and return values
6191 R5-R10: parameter passing
6192 R13: small data area pointer
6196 (U-Boot also uses R12 as internal GOT pointer. r12
6197 is a volatile register so r12 needs to be reset when
6198 going back and forth between asm and C)
6200 ==> U-Boot will use R2 to hold a pointer to the global data
6202 Note: on PPC, we could use a static initializer (since the
6203 address of the global data structure is known at compile time),
6204 but it turned out that reserving a register results in somewhat
6205 smaller code - although the code savings are not that big (on
6206 average for all boards 752 bytes for the whole U-Boot image,
6207 624 text + 127 data).
6209 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
6210 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
6212 ==> U-Boot will use P3 to hold a pointer to the global data
6214 On ARM, the following registers are used:
6216 R0: function argument word/integer result
6217 R1-R3: function argument word
6218 R9: platform specific
6219 R10: stack limit (used only if stack checking is enabled)
6220 R11: argument (frame) pointer
6221 R12: temporary workspace
6224 R15: program counter
6226 ==> U-Boot will use R9 to hold a pointer to the global data
6228 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
6230 On Nios II, the ABI is documented here:
6231 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
6233 ==> U-Boot will use gp to hold a pointer to the global data
6235 Note: on Nios II, we give "-G0" option to gcc and don't use gp
6236 to access small data sections, so gp is free.
6238 On NDS32, the following registers are used:
6240 R0-R1: argument/return
6242 R15: temporary register for assembler
6243 R16: trampoline register
6244 R28: frame pointer (FP)
6245 R29: global pointer (GP)
6246 R30: link register (LP)
6247 R31: stack pointer (SP)
6248 PC: program counter (PC)
6250 ==> U-Boot will use R10 to hold a pointer to the global data
6252 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
6253 or current versions of GCC may "optimize" the code too much.
6258 U-Boot runs in system state and uses physical addresses, i.e. the
6259 MMU is not used either for address mapping nor for memory protection.
6261 The available memory is mapped to fixed addresses using the memory
6262 controller. In this process, a contiguous block is formed for each
6263 memory type (Flash, SDRAM, SRAM), even when it consists of several
6264 physical memory banks.
6266 U-Boot is installed in the first 128 kB of the first Flash bank (on
6267 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
6268 booting and sizing and initializing DRAM, the code relocates itself
6269 to the upper end of DRAM. Immediately below the U-Boot code some
6270 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
6271 configuration setting]. Below that, a structure with global Board
6272 Info data is placed, followed by the stack (growing downward).
6274 Additionally, some exception handler code is copied to the low 8 kB
6275 of DRAM (0x00000000 ... 0x00001FFF).
6277 So a typical memory configuration with 16 MB of DRAM could look like
6280 0x0000 0000 Exception Vector code
6283 0x0000 2000 Free for Application Use
6289 0x00FB FF20 Monitor Stack (Growing downward)
6290 0x00FB FFAC Board Info Data and permanent copy of global data
6291 0x00FC 0000 Malloc Arena
6294 0x00FE 0000 RAM Copy of Monitor Code
6295 ... eventually: LCD or video framebuffer
6296 ... eventually: pRAM (Protected RAM - unchanged by reset)
6297 0x00FF FFFF [End of RAM]
6300 System Initialization:
6301 ----------------------
6303 In the reset configuration, U-Boot starts at the reset entry point
6304 (on most PowerPC systems at address 0x00000100). Because of the reset
6305 configuration for CS0# this is a mirror of the onboard Flash memory.
6306 To be able to re-map memory U-Boot then jumps to its link address.
6307 To be able to implement the initialization code in C, a (small!)
6308 initial stack is set up in the internal Dual Ported RAM (in case CPUs
6309 which provide such a feature like MPC8xx or MPC8260), or in a locked
6310 part of the data cache. After that, U-Boot initializes the CPU core,
6311 the caches and the SIU.
6313 Next, all (potentially) available memory banks are mapped using a
6314 preliminary mapping. For example, we put them on 512 MB boundaries
6315 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
6316 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
6317 programmed for SDRAM access. Using the temporary configuration, a
6318 simple memory test is run that determines the size of the SDRAM
6321 When there is more than one SDRAM bank, and the banks are of
6322 different size, the largest is mapped first. For equal size, the first
6323 bank (CS2#) is mapped first. The first mapping is always for address
6324 0x00000000, with any additional banks following immediately to create
6325 contiguous memory starting from 0.
6327 Then, the monitor installs itself at the upper end of the SDRAM area
6328 and allocates memory for use by malloc() and for the global Board
6329 Info data; also, the exception vector code is copied to the low RAM
6330 pages, and the final stack is set up.
6332 Only after this relocation will you have a "normal" C environment;
6333 until that you are restricted in several ways, mostly because you are
6334 running from ROM, and because the code will have to be relocated to a
6338 U-Boot Porting Guide:
6339 ----------------------
6341 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
6345 int main(int argc, char *argv[])
6347 sighandler_t no_more_time;
6349 signal(SIGALRM, no_more_time);
6350 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
6352 if (available_money > available_manpower) {
6353 Pay consultant to port U-Boot;
6357 Download latest U-Boot source;
6359 Subscribe to u-boot mailing list;
6362 email("Hi, I am new to U-Boot, how do I get started?");
6365 Read the README file in the top level directory;
6366 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
6367 Read applicable doc/*.README;
6368 Read the source, Luke;
6369 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
6372 if (available_money > toLocalCurrency ($2500))
6375 Add a lot of aggravation and time;
6377 if (a similar board exists) { /* hopefully... */
6378 cp -a board/<similar> board/<myboard>
6379 cp include/configs/<similar>.h include/configs/<myboard>.h
6381 Create your own board support subdirectory;
6382 Create your own board include/configs/<myboard>.h file;
6384 Edit new board/<myboard> files
6385 Edit new include/configs/<myboard>.h
6390 Add / modify source code;
6394 email("Hi, I am having problems...");
6396 Send patch file to the U-Boot email list;
6397 if (reasonable critiques)
6398 Incorporate improvements from email list code review;
6400 Defend code as written;
6406 void no_more_time (int sig)
6415 All contributions to U-Boot should conform to the Linux kernel
6416 coding style; see the file "Documentation/CodingStyle" and the script
6417 "scripts/Lindent" in your Linux kernel source directory.
6419 Source files originating from a different project (for example the
6420 MTD subsystem) are generally exempt from these guidelines and are not
6421 reformated to ease subsequent migration to newer versions of those
6424 Please note that U-Boot is implemented in C (and to some small parts in
6425 Assembler); no C++ is used, so please do not use C++ style comments (//)
6428 Please also stick to the following formatting rules:
6429 - remove any trailing white space
6430 - use TAB characters for indentation and vertical alignment, not spaces
6431 - make sure NOT to use DOS '\r\n' line feeds
6432 - do not add more than 2 consecutive empty lines to source files
6433 - do not add trailing empty lines to source files
6435 Submissions which do not conform to the standards may be returned
6436 with a request to reformat the changes.
6442 Since the number of patches for U-Boot is growing, we need to
6443 establish some rules. Submissions which do not conform to these rules
6444 may be rejected, even when they contain important and valuable stuff.
6446 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
6448 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
6449 see http://lists.denx.de/mailman/listinfo/u-boot
6451 When you send a patch, please include the following information with
6454 * For bug fixes: a description of the bug and how your patch fixes
6455 this bug. Please try to include a way of demonstrating that the
6456 patch actually fixes something.
6458 * For new features: a description of the feature and your
6461 * A CHANGELOG entry as plaintext (separate from the patch)
6463 * For major contributions, your entry to the CREDITS file
6465 * When you add support for a new board, don't forget to add a
6466 maintainer e-mail address to the boards.cfg file, too.
6468 * If your patch adds new configuration options, don't forget to
6469 document these in the README file.
6471 * The patch itself. If you are using git (which is *strongly*
6472 recommended) you can easily generate the patch using the
6473 "git format-patch". If you then use "git send-email" to send it to
6474 the U-Boot mailing list, you will avoid most of the common problems
6475 with some other mail clients.
6477 If you cannot use git, use "diff -purN OLD NEW". If your version of
6478 diff does not support these options, then get the latest version of
6481 The current directory when running this command shall be the parent
6482 directory of the U-Boot source tree (i. e. please make sure that
6483 your patch includes sufficient directory information for the
6486 We prefer patches as plain text. MIME attachments are discouraged,
6487 and compressed attachments must not be used.
6489 * If one logical set of modifications affects or creates several
6490 files, all these changes shall be submitted in a SINGLE patch file.
6492 * Changesets that contain different, unrelated modifications shall be
6493 submitted as SEPARATE patches, one patch per changeset.
6498 * Before sending the patch, run the MAKEALL script on your patched
6499 source tree and make sure that no errors or warnings are reported
6500 for any of the boards.
6502 * Keep your modifications to the necessary minimum: A patch
6503 containing several unrelated changes or arbitrary reformats will be
6504 returned with a request to re-formatting / split it.
6506 * If you modify existing code, make sure that your new code does not
6507 add to the memory footprint of the code ;-) Small is beautiful!
6508 When adding new features, these should compile conditionally only
6509 (using #ifdef), and the resulting code with the new feature
6510 disabled must not need more memory than the old code without your
6513 * Remember that there is a size limit of 100 kB per message on the
6514 u-boot mailing list. Bigger patches will be moderated. If they are
6515 reasonable and not too big, they will be acknowledged. But patches
6516 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob