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 /arm Files generic to ARM architecture
136 /cpu CPU specific files
137 /arm720t Files specific to ARM 720 CPUs
138 /arm920t Files specific to ARM 920 CPUs
139 /at91 Files specific to Atmel AT91RM9200 CPU
140 /imx Files specific to Freescale MC9328 i.MX CPUs
141 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
142 /arm925t Files specific to ARM 925 CPUs
143 /arm926ejs Files specific to ARM 926 CPUs
144 /arm1136 Files specific to ARM 1136 CPUs
145 /ixp Files specific to Intel XScale IXP CPUs
146 /pxa Files specific to Intel XScale PXA CPUs
147 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
148 /lib Architecture specific library files
149 /avr32 Files generic to AVR32 architecture
150 /cpu CPU specific files
151 /lib Architecture specific library files
152 /blackfin Files generic to Analog Devices Blackfin architecture
153 /cpu CPU specific files
154 /lib Architecture specific library files
155 /x86 Files generic to x86 architecture
156 /cpu CPU specific files
157 /lib Architecture specific library files
158 /m68k Files generic to m68k architecture
159 /cpu CPU specific files
160 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
161 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
162 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
163 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
164 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
165 /lib Architecture specific library files
166 /microblaze Files generic to microblaze architecture
167 /cpu CPU specific files
168 /lib Architecture specific library files
169 /mips Files generic to MIPS architecture
170 /cpu CPU specific files
171 /mips32 Files specific to MIPS32 CPUs
172 /xburst Files specific to Ingenic XBurst CPUs
173 /lib Architecture specific library files
174 /nds32 Files generic to NDS32 architecture
175 /cpu CPU specific files
176 /n1213 Files specific to Andes Technology N1213 CPUs
177 /lib Architecture specific library files
178 /nios2 Files generic to Altera NIOS2 architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /powerpc Files generic to PowerPC architecture
182 /cpu CPU specific files
183 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
184 /mpc5xx Files specific to Freescale MPC5xx CPUs
185 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
186 /mpc8xx Files specific to Freescale MPC8xx CPUs
187 /mpc824x Files specific to Freescale MPC824x CPUs
188 /mpc8260 Files specific to Freescale MPC8260 CPUs
189 /mpc85xx Files specific to Freescale MPC85xx CPUs
190 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
191 /lib Architecture specific library files
192 /sh Files generic to SH architecture
193 /cpu CPU specific files
194 /sh2 Files specific to sh2 CPUs
195 /sh3 Files specific to sh3 CPUs
196 /sh4 Files specific to sh4 CPUs
197 /lib Architecture specific library files
198 /sparc Files generic to SPARC architecture
199 /cpu CPU specific files
200 /leon2 Files specific to Gaisler LEON2 SPARC CPU
201 /leon3 Files specific to Gaisler LEON3 SPARC CPU
202 /lib Architecture specific library files
203 /api Machine/arch independent API for external apps
204 /board Board dependent files
205 /common Misc architecture independent functions
206 /disk Code for disk drive partition handling
207 /doc Documentation (don't expect too much)
208 /drivers Commonly used device drivers
209 /examples Example code for standalone applications, etc.
210 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
211 /include Header Files
212 /lib Files generic to all architectures
213 /libfdt Library files to support flattened device trees
214 /lzma Library files to support LZMA decompression
215 /lzo Library files to support LZO decompression
217 /post Power On Self Test
218 /rtc Real Time Clock drivers
219 /tools Tools to build S-Record or U-Boot images, etc.
221 Software Configuration:
222 =======================
224 Configuration is usually done using C preprocessor defines; the
225 rationale behind that is to avoid dead code whenever possible.
227 There are two classes of configuration variables:
229 * Configuration _OPTIONS_:
230 These are selectable by the user and have names beginning with
233 * Configuration _SETTINGS_:
234 These depend on the hardware etc. and should not be meddled with if
235 you don't know what you're doing; they have names beginning with
238 Later we will add a configuration tool - probably similar to or even
239 identical to what's used for the Linux kernel. Right now, we have to
240 do the configuration by hand, which means creating some symbolic
241 links and editing some configuration files. We use the TQM8xxL boards
245 Selection of Processor Architecture and Board Type:
246 ---------------------------------------------------
248 For all supported boards there are ready-to-use default
249 configurations available; just type "make <board_name>_config".
251 Example: For a TQM823L module type:
256 For the Cogent platform, you need to specify the CPU type as well;
257 e.g. "make cogent_mpc8xx_config". And also configure the cogent
258 directory according to the instructions in cogent/README.
261 Configuration Options:
262 ----------------------
264 Configuration depends on the combination of board and CPU type; all
265 such information is kept in a configuration file
266 "include/configs/<board_name>.h".
268 Example: For a TQM823L module, all configuration settings are in
269 "include/configs/TQM823L.h".
272 Many of the options are named exactly as the corresponding Linux
273 kernel configuration options. The intention is to make it easier to
274 build a config tool - later.
277 The following options need to be configured:
279 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
281 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
283 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
284 Define exactly one, e.g. CONFIG_ATSTK1002
286 - CPU Module Type: (if CONFIG_COGENT is defined)
287 Define exactly one of
289 --- FIXME --- not tested yet:
290 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
291 CONFIG_CMA287_23, CONFIG_CMA287_50
293 - Motherboard Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
295 CONFIG_CMA101, CONFIG_CMA102
297 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
298 Define one or more of
301 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
302 Define one or more of
303 CONFIG_LCD_HEARTBEAT - update a character position on
304 the LCD display every second with
307 - Board flavour: (if CONFIG_MPC8260ADS is defined)
310 CONFIG_SYS_8260ADS - original MPC8260ADS
311 CONFIG_SYS_8266ADS - MPC8266ADS
312 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
313 CONFIG_SYS_8272ADS - MPC8272ADS
315 - Marvell Family Member
316 CONFIG_SYS_MVFS - define it if you want to enable
317 multiple fs option at one time
318 for marvell soc family
320 - MPC824X Family Member (if CONFIG_MPC824X is defined)
321 Define exactly one of
322 CONFIG_MPC8240, CONFIG_MPC8245
324 - 8xx CPU Options: (if using an MPC8xx CPU)
325 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
326 get_gclk_freq() cannot work
327 e.g. if there is no 32KHz
328 reference PIT/RTC clock
329 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
332 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
333 CONFIG_SYS_8xx_CPUCLK_MIN
334 CONFIG_SYS_8xx_CPUCLK_MAX
335 CONFIG_8xx_CPUCLK_DEFAULT
336 See doc/README.MPC866
338 CONFIG_SYS_MEASURE_CPUCLK
340 Define this to measure the actual CPU clock instead
341 of relying on the correctness of the configured
342 values. Mostly useful for board bringup to make sure
343 the PLL is locked at the intended frequency. Note
344 that this requires a (stable) reference clock (32 kHz
345 RTC clock or CONFIG_SYS_8XX_XIN)
347 CONFIG_SYS_DELAYED_ICACHE
349 Define this option if you want to enable the
350 ICache only when Code runs from RAM.
355 Specifies that the core is a 64-bit PowerPC implementation (implements
356 the "64" category of the Power ISA). This is necessary for ePAPR
357 compliance, among other possible reasons.
359 CONFIG_SYS_FSL_TBCLK_DIV
361 Defines the core time base clock divider ratio compared to the
362 system clock. On most PQ3 devices this is 8, on newer QorIQ
363 devices it can be 16 or 32. The ratio varies from SoC to Soc.
365 CONFIG_SYS_FSL_PCIE_COMPAT
367 Defines the string to utilize when trying to match PCIe device
368 tree nodes for the given platform.
370 CONFIG_SYS_PPC_E500_DEBUG_TLB
372 Enables a temporary TLB entry to be used during boot to work
373 around limitations in e500v1 and e500v2 external debugger
374 support. This reduces the portions of the boot code where
375 breakpoints and single stepping do not work. The value of this
376 symbol should be set to the TLB1 entry to be used for this
379 CONFIG_SYS_FSL_ERRATUM_A004510
381 Enables a workaround for erratum A004510. If set,
382 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
383 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
385 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
386 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
388 Defines one or two SoC revisions (low 8 bits of SVR)
389 for which the A004510 workaround should be applied.
391 The rest of SVR is either not relevant to the decision
392 of whether the erratum is present (e.g. p2040 versus
393 p2041) or is implied by the build target, which controls
394 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
396 See Freescale App Note 4493 for more information about
399 CONFIG_A003399_NOR_WORKAROUND
400 Enables a workaround for IFC erratum A003399. It is only
401 requred during NOR boot.
403 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
405 This is the value to write into CCSR offset 0x18600
406 according to the A004510 workaround.
408 CONFIG_SYS_FSL_DSP_DDR_ADDR
409 This value denotes start offset of DDR memory which is
410 connected exclusively to the DSP cores.
412 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
413 This value denotes start offset of M2 memory
414 which is directly connected to the DSP core.
416 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
417 This value denotes start offset of M3 memory which is directly
418 connected to the DSP core.
420 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
421 This value denotes start offset of DSP CCSR space.
423 CONFIG_SYS_FSL_DDR_EMU
424 Specify emulator support for DDR. Some DDR features such as
425 deskew training are not available.
427 - Generic CPU options:
428 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
430 Defines the endianess of the CPU. Implementation of those
431 values is arch specific.
433 - Intel Monahans options:
434 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
436 Defines the Monahans run mode to oscillator
437 ratio. Valid values are 8, 16, 24, 31. The core
438 frequency is this value multiplied by 13 MHz.
440 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
442 Defines the Monahans turbo mode to oscillator
443 ratio. Valid values are 1 (default if undefined) and
444 2. The core frequency as calculated above is multiplied
448 CONFIG_SYS_INIT_SP_OFFSET
450 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
451 pointer. This is needed for the temporary stack before
454 CONFIG_SYS_MIPS_CACHE_MODE
456 Cache operation mode for the MIPS CPU.
457 See also arch/mips/include/asm/mipsregs.h.
459 CONF_CM_CACHABLE_NO_WA
462 CONF_CM_CACHABLE_NONCOHERENT
466 CONF_CM_CACHABLE_ACCELERATED
468 CONFIG_SYS_XWAY_EBU_BOOTCFG
470 Special option for Lantiq XWAY SoCs for booting from NOR flash.
471 See also arch/mips/cpu/mips32/start.S.
473 CONFIG_XWAY_SWAP_BYTES
475 Enable compilation of tools/xway-swap-bytes needed for Lantiq
476 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
477 be swapped if a flash programmer is used.
480 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
482 Select high exception vectors of the ARM core, e.g., do not
483 clear the V bit of the c1 register of CP15.
485 CONFIG_SYS_THUMB_BUILD
487 Use this flag to build U-Boot using the Thumb instruction
488 set for ARM architectures. Thumb instruction set provides
489 better code density. For ARM architectures that support
490 Thumb2 this flag will result in Thumb2 code generated by
493 CONFIG_ARM_ERRATA_716044
494 CONFIG_ARM_ERRATA_742230
495 CONFIG_ARM_ERRATA_743622
496 CONFIG_ARM_ERRATA_751472
498 If set, the workarounds for these ARM errata are applied early
499 during U-Boot startup. Note that these options force the
500 workarounds to be applied; no CPU-type/version detection
501 exists, unlike the similar options in the Linux kernel. Do not
502 set these options unless they apply!
507 The frequency of the timer returned by get_timer().
508 get_timer() must operate in milliseconds and this CONFIG
509 option must be set to 1000.
511 - Linux Kernel Interface:
514 U-Boot stores all clock information in Hz
515 internally. For binary compatibility with older Linux
516 kernels (which expect the clocks passed in the
517 bd_info data to be in MHz) the environment variable
518 "clocks_in_mhz" can be defined so that U-Boot
519 converts clock data to MHZ before passing it to the
521 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
522 "clocks_in_mhz=1" is automatically included in the
525 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
527 When transferring memsize parameter to linux, some versions
528 expect it to be in bytes, others in MB.
529 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
533 New kernel versions are expecting firmware settings to be
534 passed using flattened device trees (based on open firmware
538 * New libfdt-based support
539 * Adds the "fdt" command
540 * The bootm command automatically updates the fdt
542 OF_CPU - The proper name of the cpus node (only required for
543 MPC512X and MPC5xxx based boards).
544 OF_SOC - The proper name of the soc node (only required for
545 MPC512X and MPC5xxx based boards).
546 OF_TBCLK - The timebase frequency.
547 OF_STDOUT_PATH - The path to the console device
549 boards with QUICC Engines require OF_QE to set UCC MAC
552 CONFIG_OF_BOARD_SETUP
554 Board code has addition modification that it wants to make
555 to the flat device tree before handing it off to the kernel
559 This define fills in the correct boot CPU in the boot
560 param header, the default value is zero if undefined.
564 U-Boot can detect if an IDE device is present or not.
565 If not, and this new config option is activated, U-Boot
566 removes the ATA node from the DTS before booting Linux,
567 so the Linux IDE driver does not probe the device and
568 crash. This is needed for buggy hardware (uc101) where
569 no pull down resistor is connected to the signal IDE5V_DD7.
571 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
573 This setting is mandatory for all boards that have only one
574 machine type and must be used to specify the machine type
575 number as it appears in the ARM machine registry
576 (see http://www.arm.linux.org.uk/developer/machines/).
577 Only boards that have multiple machine types supported
578 in a single configuration file and the machine type is
579 runtime discoverable, do not have to use this setting.
581 - vxWorks boot parameters:
583 bootvx constructs a valid bootline using the following
584 environments variables: bootfile, ipaddr, serverip, hostname.
585 It loads the vxWorks image pointed bootfile.
587 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
588 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
589 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
590 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
592 CONFIG_SYS_VXWORKS_ADD_PARAMS
594 Add it at the end of the bootline. E.g "u=username pw=secret"
596 Note: If a "bootargs" environment is defined, it will overwride
597 the defaults discussed just above.
599 - Cache Configuration:
600 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
601 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
602 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
604 - Cache Configuration for ARM:
605 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
607 CONFIG_SYS_PL310_BASE - Physical base address of PL310
608 controller register space
613 Define this if you want support for Amba PrimeCell PL010 UARTs.
617 Define this if you want support for Amba PrimeCell PL011 UARTs.
621 If you have Amba PrimeCell PL011 UARTs, set this variable to
622 the clock speed of the UARTs.
626 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
627 define this to a list of base addresses for each (supported)
628 port. See e.g. include/configs/versatile.h
630 CONFIG_PL011_SERIAL_RLCR
632 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
633 have separate receive and transmit line control registers. Set
634 this variable to initialize the extra register.
636 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
638 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
639 boot loader that has already initialized the UART. Define this
640 variable to flush the UART at init time.
644 Depending on board, define exactly one serial port
645 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
646 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
647 console by defining CONFIG_8xx_CONS_NONE
649 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
650 port routines must be defined elsewhere
651 (i.e. serial_init(), serial_getc(), ...)
654 Enables console device for a color framebuffer. Needs following
655 defines (cf. smiLynxEM, i8042)
656 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
658 VIDEO_HW_RECTFILL graphic chip supports
661 VIDEO_HW_BITBLT graphic chip supports
662 bit-blit (cf. smiLynxEM)
663 VIDEO_VISIBLE_COLS visible pixel columns
665 VIDEO_VISIBLE_ROWS visible pixel rows
666 VIDEO_PIXEL_SIZE bytes per pixel
667 VIDEO_DATA_FORMAT graphic data format
668 (0-5, cf. cfb_console.c)
669 VIDEO_FB_ADRS framebuffer address
670 VIDEO_KBD_INIT_FCT keyboard int fct
671 (i.e. i8042_kbd_init())
672 VIDEO_TSTC_FCT test char fct
674 VIDEO_GETC_FCT get char fct
676 CONFIG_CONSOLE_CURSOR cursor drawing on/off
677 (requires blink timer
679 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
680 CONFIG_CONSOLE_TIME display time/date info in
682 (requires CONFIG_CMD_DATE)
683 CONFIG_VIDEO_LOGO display Linux logo in
685 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
686 linux_logo.h for logo.
687 Requires CONFIG_VIDEO_LOGO
688 CONFIG_CONSOLE_EXTRA_INFO
689 additional board info beside
692 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
693 a limited number of ANSI escape sequences (cursor control,
694 erase functions and limited graphics rendition control).
696 When CONFIG_CFB_CONSOLE is defined, video console is
697 default i/o. Serial console can be forced with
698 environment 'console=serial'.
700 When CONFIG_SILENT_CONSOLE is defined, all console
701 messages (by U-Boot and Linux!) can be silenced with
702 the "silent" environment variable. See
703 doc/README.silent for more information.
706 CONFIG_BAUDRATE - in bps
707 Select one of the baudrates listed in
708 CONFIG_SYS_BAUDRATE_TABLE, see below.
709 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
711 - Console Rx buffer length
712 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
713 the maximum receive buffer length for the SMC.
714 This option is actual only for 82xx and 8xx possible.
715 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
716 must be defined, to setup the maximum idle timeout for
719 - Pre-Console Buffer:
720 Prior to the console being initialised (i.e. serial UART
721 initialised etc) all console output is silently discarded.
722 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
723 buffer any console messages prior to the console being
724 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
725 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
726 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
727 bytes are output before the console is initialised, the
728 earlier bytes are discarded.
730 'Sane' compilers will generate smaller code if
731 CONFIG_PRE_CON_BUF_SZ is a power of 2
733 - Safe printf() functions
734 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
735 the printf() functions. These are defined in
736 include/vsprintf.h and include snprintf(), vsnprintf() and
737 so on. Code size increase is approximately 300-500 bytes.
738 If this option is not given then these functions will
739 silently discard their buffer size argument - this means
740 you are not getting any overflow checking in this case.
742 - Boot Delay: CONFIG_BOOTDELAY - in seconds
743 Delay before automatically booting the default image;
744 set to -1 to disable autoboot.
745 set to -2 to autoboot with no delay and not check for abort
746 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
748 See doc/README.autoboot for these options that
749 work with CONFIG_BOOTDELAY. None are required.
750 CONFIG_BOOT_RETRY_TIME
751 CONFIG_BOOT_RETRY_MIN
752 CONFIG_AUTOBOOT_KEYED
753 CONFIG_AUTOBOOT_PROMPT
754 CONFIG_AUTOBOOT_DELAY_STR
755 CONFIG_AUTOBOOT_STOP_STR
756 CONFIG_AUTOBOOT_DELAY_STR2
757 CONFIG_AUTOBOOT_STOP_STR2
758 CONFIG_ZERO_BOOTDELAY_CHECK
759 CONFIG_RESET_TO_RETRY
763 Only needed when CONFIG_BOOTDELAY is enabled;
764 define a command string that is automatically executed
765 when no character is read on the console interface
766 within "Boot Delay" after reset.
769 This can be used to pass arguments to the bootm
770 command. The value of CONFIG_BOOTARGS goes into the
771 environment value "bootargs".
773 CONFIG_RAMBOOT and CONFIG_NFSBOOT
774 The value of these goes into the environment as
775 "ramboot" and "nfsboot" respectively, and can be used
776 as a convenience, when switching between booting from
782 When this option is #defined, the existence of the
783 environment variable "preboot" will be checked
784 immediately before starting the CONFIG_BOOTDELAY
785 countdown and/or running the auto-boot command resp.
786 entering interactive mode.
788 This feature is especially useful when "preboot" is
789 automatically generated or modified. For an example
790 see the LWMON board specific code: here "preboot" is
791 modified when the user holds down a certain
792 combination of keys on the (special) keyboard when
795 - Serial Download Echo Mode:
797 If defined to 1, all characters received during a
798 serial download (using the "loads" command) are
799 echoed back. This might be needed by some terminal
800 emulations (like "cu"), but may as well just take
801 time on others. This setting #define's the initial
802 value of the "loads_echo" environment variable.
804 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
806 Select one of the baudrates listed in
807 CONFIG_SYS_BAUDRATE_TABLE, see below.
810 Monitor commands can be included or excluded
811 from the build by using the #include files
812 <config_cmd_all.h> and #undef'ing unwanted
813 commands, or using <config_cmd_default.h>
814 and augmenting with additional #define's
817 The default command configuration includes all commands
818 except those marked below with a "*".
820 CONFIG_CMD_ASKENV * ask for env variable
821 CONFIG_CMD_BDI bdinfo
822 CONFIG_CMD_BEDBUG * Include BedBug Debugger
823 CONFIG_CMD_BMP * BMP support
824 CONFIG_CMD_BSP * Board specific commands
825 CONFIG_CMD_BOOTD bootd
826 CONFIG_CMD_CACHE * icache, dcache
827 CONFIG_CMD_CONSOLE coninfo
828 CONFIG_CMD_CRC32 * crc32
829 CONFIG_CMD_DATE * support for RTC, date/time...
830 CONFIG_CMD_DHCP * DHCP support
831 CONFIG_CMD_DIAG * Diagnostics
832 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
833 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
834 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
835 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
836 CONFIG_CMD_DTT * Digital Therm and Thermostat
837 CONFIG_CMD_ECHO echo arguments
838 CONFIG_CMD_EDITENV edit env variable
839 CONFIG_CMD_EEPROM * EEPROM read/write support
840 CONFIG_CMD_ELF * bootelf, bootvx
841 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
842 CONFIG_CMD_ENV_FLAGS * display details about env flags
843 CONFIG_CMD_EXPORTENV * export the environment
844 CONFIG_CMD_EXT2 * ext2 command support
845 CONFIG_CMD_EXT4 * ext4 command support
846 CONFIG_CMD_SAVEENV saveenv
847 CONFIG_CMD_FDC * Floppy Disk Support
848 CONFIG_CMD_FAT * FAT command support
849 CONFIG_CMD_FDOS * Dos diskette Support
850 CONFIG_CMD_FLASH flinfo, erase, protect
851 CONFIG_CMD_FPGA FPGA device initialization support
852 CONFIG_CMD_FUSE * Device fuse support
853 CONFIG_CMD_GETTIME * Get time since boot
854 CONFIG_CMD_GO * the 'go' command (exec code)
855 CONFIG_CMD_GREPENV * search environment
856 CONFIG_CMD_HASH * calculate hash / digest
857 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
858 CONFIG_CMD_I2C * I2C serial bus support
859 CONFIG_CMD_IDE * IDE harddisk support
860 CONFIG_CMD_IMI iminfo
861 CONFIG_CMD_IMLS List all images found in NOR flash
862 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
863 CONFIG_CMD_IMMAP * IMMR dump support
864 CONFIG_CMD_IMPORTENV * import an environment
865 CONFIG_CMD_INI * import data from an ini file into the env
866 CONFIG_CMD_IRQ * irqinfo
867 CONFIG_CMD_ITEST Integer/string test of 2 values
868 CONFIG_CMD_JFFS2 * JFFS2 Support
869 CONFIG_CMD_KGDB * kgdb
870 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
871 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
873 CONFIG_CMD_LOADB loadb
874 CONFIG_CMD_LOADS loads
875 CONFIG_CMD_MD5SUM * print md5 message digest
876 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
877 CONFIG_CMD_MEMINFO * Display detailed memory information
878 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
880 CONFIG_CMD_MEMTEST * mtest
881 CONFIG_CMD_MISC Misc functions like sleep etc
882 CONFIG_CMD_MMC * MMC memory mapped support
883 CONFIG_CMD_MII * MII utility commands
884 CONFIG_CMD_MTDPARTS * MTD partition support
885 CONFIG_CMD_NAND * NAND support
886 CONFIG_CMD_NET bootp, tftpboot, rarpboot
887 CONFIG_CMD_NFS NFS support
888 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
889 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
890 CONFIG_CMD_PCI * pciinfo
891 CONFIG_CMD_PCMCIA * PCMCIA support
892 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
894 CONFIG_CMD_PORTIO * Port I/O
895 CONFIG_CMD_READ * Read raw data from partition
896 CONFIG_CMD_REGINFO * Register dump
897 CONFIG_CMD_RUN run command in env variable
898 CONFIG_CMD_SANDBOX * sb command to access sandbox features
899 CONFIG_CMD_SAVES * save S record dump
900 CONFIG_CMD_SCSI * SCSI Support
901 CONFIG_CMD_SDRAM * print SDRAM configuration information
902 (requires CONFIG_CMD_I2C)
903 CONFIG_CMD_SETGETDCR Support for DCR Register access
905 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
906 CONFIG_CMD_SHA1SUM * print sha1 memory digest
907 (requires CONFIG_CMD_MEMORY)
908 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
909 CONFIG_CMD_SOURCE "source" command Support
910 CONFIG_CMD_SPI * SPI serial bus support
911 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
912 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
913 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
914 CONFIG_CMD_TIMER * access to the system tick timer
915 CONFIG_CMD_USB * USB support
916 CONFIG_CMD_CDP * Cisco Discover Protocol support
917 CONFIG_CMD_MFSL * Microblaze FSL support
918 CONFIG_CMD_XIMG Load part of Multi Image
921 EXAMPLE: If you want all functions except of network
922 support you can write:
924 #include "config_cmd_all.h"
925 #undef CONFIG_CMD_NET
928 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
930 Note: Don't enable the "icache" and "dcache" commands
931 (configuration option CONFIG_CMD_CACHE) unless you know
932 what you (and your U-Boot users) are doing. Data
933 cache cannot be enabled on systems like the 8xx or
934 8260 (where accesses to the IMMR region must be
935 uncached), and it cannot be disabled on all other
936 systems where we (mis-) use the data cache to hold an
937 initial stack and some data.
940 XXX - this list needs to get updated!
942 - Regular expression support:
944 If this variable is defined, U-Boot is linked against
945 the SLRE (Super Light Regular Expression) library,
946 which adds regex support to some commands, as for
947 example "env grep" and "setexpr".
951 If this variable is defined, U-Boot will use a device tree
952 to configure its devices, instead of relying on statically
953 compiled #defines in the board file. This option is
954 experimental and only available on a few boards. The device
955 tree is available in the global data as gd->fdt_blob.
957 U-Boot needs to get its device tree from somewhere. This can
958 be done using one of the two options below:
961 If this variable is defined, U-Boot will embed a device tree
962 binary in its image. This device tree file should be in the
963 board directory and called <soc>-<board>.dts. The binary file
964 is then picked up in board_init_f() and made available through
965 the global data structure as gd->blob.
968 If this variable is defined, U-Boot will build a device tree
969 binary. It will be called u-boot.dtb. Architecture-specific
970 code will locate it at run-time. Generally this works by:
972 cat u-boot.bin u-boot.dtb >image.bin
974 and in fact, U-Boot does this for you, creating a file called
975 u-boot-dtb.bin which is useful in the common case. You can
976 still use the individual files if you need something more
981 If this variable is defined, it enables watchdog
982 support for the SoC. There must be support in the SoC
983 specific code for a watchdog. For the 8xx and 8260
984 CPUs, the SIU Watchdog feature is enabled in the SYPCR
985 register. When supported for a specific SoC is
986 available, then no further board specific code should
990 When using a watchdog circuitry external to the used
991 SoC, then define this variable and provide board
992 specific code for the "hw_watchdog_reset" function.
995 CONFIG_VERSION_VARIABLE
996 If this variable is defined, an environment variable
997 named "ver" is created by U-Boot showing the U-Boot
998 version as printed by the "version" command.
999 Any change to this variable will be reverted at the
1004 When CONFIG_CMD_DATE is selected, the type of the RTC
1005 has to be selected, too. Define exactly one of the
1008 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1009 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1010 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1011 CONFIG_RTC_MC146818 - use MC146818 RTC
1012 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1013 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1014 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1015 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1016 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1017 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1018 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1019 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1022 Note that if the RTC uses I2C, then the I2C interface
1023 must also be configured. See I2C Support, below.
1026 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1027 CONFIG_PCA953X_INFO - enable pca953x info command
1029 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1030 chip-ngpio pairs that tell the PCA953X driver the number of
1031 pins supported by a particular chip.
1033 Note that if the GPIO device uses I2C, then the I2C interface
1034 must also be configured. See I2C Support, below.
1036 - Timestamp Support:
1038 When CONFIG_TIMESTAMP is selected, the timestamp
1039 (date and time) of an image is printed by image
1040 commands like bootm or iminfo. This option is
1041 automatically enabled when you select CONFIG_CMD_DATE .
1043 - Partition Labels (disklabels) Supported:
1044 Zero or more of the following:
1045 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1046 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1047 Intel architecture, USB sticks, etc.
1048 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1049 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1050 bootloader. Note 2TB partition limit; see
1052 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1054 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1055 CONFIG_CMD_SCSI) you must configure support for at
1056 least one non-MTD partition type as well.
1059 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1060 board configurations files but used nowhere!
1062 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1063 be performed by calling the function
1064 ide_set_reset(int reset)
1065 which has to be defined in a board specific file
1070 Set this to enable ATAPI support.
1075 Set this to enable support for disks larger than 137GB
1076 Also look at CONFIG_SYS_64BIT_LBA.
1077 Whithout these , LBA48 support uses 32bit variables and will 'only'
1078 support disks up to 2.1TB.
1080 CONFIG_SYS_64BIT_LBA:
1081 When enabled, makes the IDE subsystem use 64bit sector addresses.
1085 At the moment only there is only support for the
1086 SYM53C8XX SCSI controller; define
1087 CONFIG_SCSI_SYM53C8XX to enable it.
1089 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1090 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1091 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1092 maximum numbers of LUNs, SCSI ID's and target
1094 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1096 The environment variable 'scsidevs' is set to the number of
1097 SCSI devices found during the last scan.
1099 - NETWORK Support (PCI):
1101 Support for Intel 8254x/8257x gigabit chips.
1104 Utility code for direct access to the SPI bus on Intel 8257x.
1105 This does not do anything useful unless you set at least one
1106 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1108 CONFIG_E1000_SPI_GENERIC
1109 Allow generic access to the SPI bus on the Intel 8257x, for
1110 example with the "sspi" command.
1113 Management command for E1000 devices. When used on devices
1114 with SPI support you can reprogram the EEPROM from U-Boot.
1116 CONFIG_E1000_FALLBACK_MAC
1117 default MAC for empty EEPROM after production.
1120 Support for Intel 82557/82559/82559ER chips.
1121 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1122 write routine for first time initialisation.
1125 Support for Digital 2114x chips.
1126 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1127 modem chip initialisation (KS8761/QS6611).
1130 Support for National dp83815 chips.
1133 Support for National dp8382[01] gigabit chips.
1135 - NETWORK Support (other):
1137 CONFIG_DRIVER_AT91EMAC
1138 Support for AT91RM9200 EMAC.
1141 Define this to use reduced MII inteface
1143 CONFIG_DRIVER_AT91EMAC_QUIET
1144 If this defined, the driver is quiet.
1145 The driver doen't show link status messages.
1147 CONFIG_CALXEDA_XGMAC
1148 Support for the Calxeda XGMAC device
1151 Support for SMSC's LAN91C96 chips.
1153 CONFIG_LAN91C96_BASE
1154 Define this to hold the physical address
1155 of the LAN91C96's I/O space
1157 CONFIG_LAN91C96_USE_32_BIT
1158 Define this to enable 32 bit addressing
1161 Support for SMSC's LAN91C111 chip
1163 CONFIG_SMC91111_BASE
1164 Define this to hold the physical address
1165 of the device (I/O space)
1167 CONFIG_SMC_USE_32_BIT
1168 Define this if data bus is 32 bits
1170 CONFIG_SMC_USE_IOFUNCS
1171 Define this to use i/o functions instead of macros
1172 (some hardware wont work with macros)
1174 CONFIG_DRIVER_TI_EMAC
1175 Support for davinci emac
1177 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1178 Define this if you have more then 3 PHYs.
1181 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1183 CONFIG_FTGMAC100_EGIGA
1184 Define this to use GE link update with gigabit PHY.
1185 Define this if FTGMAC100 is connected to gigabit PHY.
1186 If your system has 10/100 PHY only, it might not occur
1187 wrong behavior. Because PHY usually return timeout or
1188 useless data when polling gigabit status and gigabit
1189 control registers. This behavior won't affect the
1190 correctnessof 10/100 link speed update.
1193 Support for SMSC's LAN911x and LAN921x chips
1196 Define this to hold the physical address
1197 of the device (I/O space)
1199 CONFIG_SMC911X_32_BIT
1200 Define this if data bus is 32 bits
1202 CONFIG_SMC911X_16_BIT
1203 Define this if data bus is 16 bits. If your processor
1204 automatically converts one 32 bit word to two 16 bit
1205 words you may also try CONFIG_SMC911X_32_BIT.
1208 Support for Renesas on-chip Ethernet controller
1210 CONFIG_SH_ETHER_USE_PORT
1211 Define the number of ports to be used
1213 CONFIG_SH_ETHER_PHY_ADDR
1214 Define the ETH PHY's address
1216 CONFIG_SH_ETHER_CACHE_WRITEBACK
1217 If this option is set, the driver enables cache flush.
1221 Support TPM devices.
1224 Support for i2c bus TPM devices. Only one device
1225 per system is supported at this time.
1227 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1228 Define the the i2c bus number for the TPM device
1230 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1231 Define the TPM's address on the i2c bus
1233 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1234 Define the burst count bytes upper limit
1236 CONFIG_TPM_ATMEL_TWI
1237 Support for Atmel TWI TPM device. Requires I2C support.
1240 Support for generic parallel port TPM devices. Only one device
1241 per system is supported at this time.
1243 CONFIG_TPM_TIS_BASE_ADDRESS
1244 Base address where the generic TPM device is mapped
1245 to. Contemporary x86 systems usually map it at
1249 Add tpm monitor functions.
1250 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1251 provides monitor access to authorized functions.
1254 Define this to enable the TPM support library which provides
1255 functional interfaces to some TPM commands.
1256 Requires support for a TPM device.
1258 CONFIG_TPM_AUTH_SESSIONS
1259 Define this to enable authorized functions in the TPM library.
1260 Requires CONFIG_TPM and CONFIG_SHA1.
1263 At the moment only the UHCI host controller is
1264 supported (PIP405, MIP405, MPC5200); define
1265 CONFIG_USB_UHCI to enable it.
1266 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1267 and define CONFIG_USB_STORAGE to enable the USB
1270 Supported are USB Keyboards and USB Floppy drives
1272 MPC5200 USB requires additional defines:
1274 for 528 MHz Clock: 0x0001bbbb
1278 for differential drivers: 0x00001000
1279 for single ended drivers: 0x00005000
1280 for differential drivers on PSC3: 0x00000100
1281 for single ended drivers on PSC3: 0x00004100
1282 CONFIG_SYS_USB_EVENT_POLL
1283 May be defined to allow interrupt polling
1284 instead of using asynchronous interrupts
1286 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1287 txfilltuning field in the EHCI controller on reset.
1289 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1290 interval for usb hub power-on delay.(minimum 100msec)
1293 Define the below if you wish to use the USB console.
1294 Once firmware is rebuilt from a serial console issue the
1295 command "setenv stdin usbtty; setenv stdout usbtty" and
1296 attach your USB cable. The Unix command "dmesg" should print
1297 it has found a new device. The environment variable usbtty
1298 can be set to gserial or cdc_acm to enable your device to
1299 appear to a USB host as a Linux gserial device or a
1300 Common Device Class Abstract Control Model serial device.
1301 If you select usbtty = gserial you should be able to enumerate
1303 # modprobe usbserial vendor=0xVendorID product=0xProductID
1304 else if using cdc_acm, simply setting the environment
1305 variable usbtty to be cdc_acm should suffice. The following
1306 might be defined in YourBoardName.h
1309 Define this to build a UDC device
1312 Define this to have a tty type of device available to
1313 talk to the UDC device
1316 Define this to enable the high speed support for usb
1317 device and usbtty. If this feature is enabled, a routine
1318 int is_usbd_high_speed(void)
1319 also needs to be defined by the driver to dynamically poll
1320 whether the enumeration has succeded at high speed or full
1323 CONFIG_SYS_CONSOLE_IS_IN_ENV
1324 Define this if you want stdin, stdout &/or stderr to
1328 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1329 Derive USB clock from external clock "blah"
1330 - CONFIG_SYS_USB_EXTC_CLK 0x02
1332 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1333 Derive USB clock from brgclk
1334 - CONFIG_SYS_USB_BRG_CLK 0x04
1336 If you have a USB-IF assigned VendorID then you may wish to
1337 define your own vendor specific values either in BoardName.h
1338 or directly in usbd_vendor_info.h. If you don't define
1339 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1340 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1341 should pretend to be a Linux device to it's target host.
1343 CONFIG_USBD_MANUFACTURER
1344 Define this string as the name of your company for
1345 - CONFIG_USBD_MANUFACTURER "my company"
1347 CONFIG_USBD_PRODUCT_NAME
1348 Define this string as the name of your product
1349 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1351 CONFIG_USBD_VENDORID
1352 Define this as your assigned Vendor ID from the USB
1353 Implementors Forum. This *must* be a genuine Vendor ID
1354 to avoid polluting the USB namespace.
1355 - CONFIG_USBD_VENDORID 0xFFFF
1357 CONFIG_USBD_PRODUCTID
1358 Define this as the unique Product ID
1360 - CONFIG_USBD_PRODUCTID 0xFFFF
1362 - ULPI Layer Support:
1363 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1364 the generic ULPI layer. The generic layer accesses the ULPI PHY
1365 via the platform viewport, so you need both the genric layer and
1366 the viewport enabled. Currently only Chipidea/ARC based
1367 viewport is supported.
1368 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1369 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1370 If your ULPI phy needs a different reference clock than the
1371 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1372 the appropriate value in Hz.
1375 The MMC controller on the Intel PXA is supported. To
1376 enable this define CONFIG_MMC. The MMC can be
1377 accessed from the boot prompt by mapping the device
1378 to physical memory similar to flash. Command line is
1379 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1380 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1383 Support for Renesas on-chip MMCIF controller
1385 CONFIG_SH_MMCIF_ADDR
1386 Define the base address of MMCIF registers
1389 Define the clock frequency for MMCIF
1391 - USB Device Firmware Update (DFU) class support:
1393 This enables the USB portion of the DFU USB class
1396 This enables the command "dfu" which is used to have
1397 U-Boot create a DFU class device via USB. This command
1398 requires that the "dfu_alt_info" environment variable be
1399 set and define the alt settings to expose to the host.
1402 This enables support for exposing (e)MMC devices via DFU.
1405 This enables support for exposing NAND devices via DFU.
1407 CONFIG_SYS_DFU_DATA_BUF_SIZE
1408 Dfu transfer uses a buffer before writing data to the
1409 raw storage device. Make the size (in bytes) of this buffer
1410 configurable. The size of this buffer is also configurable
1411 through the "dfu_bufsiz" environment variable.
1413 CONFIG_SYS_DFU_MAX_FILE_SIZE
1414 When updating files rather than the raw storage device,
1415 we use a static buffer to copy the file into and then write
1416 the buffer once we've been given the whole file. Define
1417 this to the maximum filesize (in bytes) for the buffer.
1418 Default is 4 MiB if undefined.
1420 - Journaling Flash filesystem support:
1421 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1422 CONFIG_JFFS2_NAND_DEV
1423 Define these for a default partition on a NAND device
1425 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1426 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1427 Define these for a default partition on a NOR device
1429 CONFIG_SYS_JFFS_CUSTOM_PART
1430 Define this to create an own partition. You have to provide a
1431 function struct part_info* jffs2_part_info(int part_num)
1433 If you define only one JFFS2 partition you may also want to
1434 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1435 to disable the command chpart. This is the default when you
1436 have not defined a custom partition
1438 - FAT(File Allocation Table) filesystem write function support:
1441 Define this to enable support for saving memory data as a
1442 file in FAT formatted partition.
1444 This will also enable the command "fatwrite" enabling the
1445 user to write files to FAT.
1447 CBFS (Coreboot Filesystem) support
1450 Define this to enable support for reading from a Coreboot
1451 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1457 Define this to enable standard (PC-Style) keyboard
1461 Standard PC keyboard driver with US (is default) and
1462 GERMAN key layout (switch via environment 'keymap=de') support.
1463 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1464 for cfb_console. Supports cursor blinking.
1467 Enables a Chrome OS keyboard using the CROS_EC interface.
1468 This uses CROS_EC to communicate with a second microcontroller
1469 which provides key scans on request.
1474 Define this to enable video support (for output to
1477 CONFIG_VIDEO_CT69000
1479 Enable Chips & Technologies 69000 Video chip
1481 CONFIG_VIDEO_SMI_LYNXEM
1482 Enable Silicon Motion SMI 712/710/810 Video chip. The
1483 video output is selected via environment 'videoout'
1484 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1487 For the CT69000 and SMI_LYNXEM drivers, videomode is
1488 selected via environment 'videomode'. Two different ways
1490 - "videomode=num" 'num' is a standard LiLo mode numbers.
1491 Following standard modes are supported (* is default):
1493 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1494 -------------+---------------------------------------------
1495 8 bits | 0x301* 0x303 0x305 0x161 0x307
1496 15 bits | 0x310 0x313 0x316 0x162 0x319
1497 16 bits | 0x311 0x314 0x317 0x163 0x31A
1498 24 bits | 0x312 0x315 0x318 ? 0x31B
1499 -------------+---------------------------------------------
1500 (i.e. setenv videomode 317; saveenv; reset;)
1502 - "videomode=bootargs" all the video parameters are parsed
1503 from the bootargs. (See drivers/video/videomodes.c)
1506 CONFIG_VIDEO_SED13806
1507 Enable Epson SED13806 driver. This driver supports 8bpp
1508 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1509 or CONFIG_VIDEO_SED13806_16BPP
1512 Enable the Freescale DIU video driver. Reference boards for
1513 SOCs that have a DIU should define this macro to enable DIU
1514 support, and should also define these other macros:
1520 CONFIG_VIDEO_SW_CURSOR
1521 CONFIG_VGA_AS_SINGLE_DEVICE
1523 CONFIG_VIDEO_BMP_LOGO
1525 The DIU driver will look for the 'video-mode' environment
1526 variable, and if defined, enable the DIU as a console during
1527 boot. See the documentation file README.video for a
1528 description of this variable.
1532 Enable the VGA video / BIOS for x86. The alternative if you
1533 are using coreboot is to use the coreboot frame buffer
1540 Define this to enable a custom keyboard support.
1541 This simply calls drv_keyboard_init() which must be
1542 defined in your board-specific files.
1543 The only board using this so far is RBC823.
1545 - LCD Support: CONFIG_LCD
1547 Define this to enable LCD support (for output to LCD
1548 display); also select one of the supported displays
1549 by defining one of these:
1553 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1555 CONFIG_NEC_NL6448AC33:
1557 NEC NL6448AC33-18. Active, color, single scan.
1559 CONFIG_NEC_NL6448BC20
1561 NEC NL6448BC20-08. 6.5", 640x480.
1562 Active, color, single scan.
1564 CONFIG_NEC_NL6448BC33_54
1566 NEC NL6448BC33-54. 10.4", 640x480.
1567 Active, color, single scan.
1571 Sharp 320x240. Active, color, single scan.
1572 It isn't 16x9, and I am not sure what it is.
1574 CONFIG_SHARP_LQ64D341
1576 Sharp LQ64D341 display, 640x480.
1577 Active, color, single scan.
1581 HLD1045 display, 640x480.
1582 Active, color, single scan.
1586 Optrex CBL50840-2 NF-FW 99 22 M5
1588 Hitachi LMG6912RPFC-00T
1592 320x240. Black & white.
1594 Normally display is black on white background; define
1595 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1597 CONFIG_LCD_ALIGNMENT
1599 Normally the LCD is page-aligned (tyically 4KB). If this is
1600 defined then the LCD will be aligned to this value instead.
1601 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1602 here, since it is cheaper to change data cache settings on
1603 a per-section basis.
1605 CONFIG_CONSOLE_SCROLL_LINES
1607 When the console need to be scrolled, this is the number of
1608 lines to scroll by. It defaults to 1. Increasing this makes
1609 the console jump but can help speed up operation when scrolling
1614 Support drawing of RLE8-compressed bitmaps on the LCD.
1618 Enables an 'i2c edid' command which can read EDID
1619 information over I2C from an attached LCD display.
1621 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1623 If this option is set, the environment is checked for
1624 a variable "splashimage". If found, the usual display
1625 of logo, copyright and system information on the LCD
1626 is suppressed and the BMP image at the address
1627 specified in "splashimage" is loaded instead. The
1628 console is redirected to the "nulldev", too. This
1629 allows for a "silent" boot where a splash screen is
1630 loaded very quickly after power-on.
1632 CONFIG_SPLASHIMAGE_GUARD
1634 If this option is set, then U-Boot will prevent the environment
1635 variable "splashimage" from being set to a problematic address
1636 (see README.displaying-bmps and README.arm-unaligned-accesses).
1637 This option is useful for targets where, due to alignment
1638 restrictions, an improperly aligned BMP image will cause a data
1639 abort. If you think you will not have problems with unaligned
1640 accesses (for example because your toolchain prevents them)
1641 there is no need to set this option.
1643 CONFIG_SPLASH_SCREEN_ALIGN
1645 If this option is set the splash image can be freely positioned
1646 on the screen. Environment variable "splashpos" specifies the
1647 position as "x,y". If a positive number is given it is used as
1648 number of pixel from left/top. If a negative number is given it
1649 is used as number of pixel from right/bottom. You can also
1650 specify 'm' for centering the image.
1653 setenv splashpos m,m
1654 => image at center of screen
1656 setenv splashpos 30,20
1657 => image at x = 30 and y = 20
1659 setenv splashpos -10,m
1660 => vertically centered image
1661 at x = dspWidth - bmpWidth - 9
1663 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1665 If this option is set, additionally to standard BMP
1666 images, gzipped BMP images can be displayed via the
1667 splashscreen support or the bmp command.
1669 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1671 If this option is set, 8-bit RLE compressed BMP images
1672 can be displayed via the splashscreen support or the
1675 - Do compresssing for memory range:
1678 If this option is set, it would use zlib deflate method
1679 to compress the specified memory at its best effort.
1681 - Compression support:
1684 Enabled by default to support gzip compressed images.
1688 If this option is set, support for bzip2 compressed
1689 images is included. If not, only uncompressed and gzip
1690 compressed images are supported.
1692 NOTE: the bzip2 algorithm requires a lot of RAM, so
1693 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1698 If this option is set, support for lzma compressed
1701 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1702 requires an amount of dynamic memory that is given by the
1705 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1707 Where lc and lp stand for, respectively, Literal context bits
1708 and Literal pos bits.
1710 This value is upper-bounded by 14MB in the worst case. Anyway,
1711 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1712 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1713 a very small buffer.
1715 Use the lzmainfo tool to determinate the lc and lp values and
1716 then calculate the amount of needed dynamic memory (ensuring
1717 the appropriate CONFIG_SYS_MALLOC_LEN value).
1721 If this option is set, support for LZO compressed images
1727 The address of PHY on MII bus.
1729 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1731 The clock frequency of the MII bus
1735 If this option is set, support for speed/duplex
1736 detection of gigabit PHY is included.
1738 CONFIG_PHY_RESET_DELAY
1740 Some PHY like Intel LXT971A need extra delay after
1741 reset before any MII register access is possible.
1742 For such PHY, set this option to the usec delay
1743 required. (minimum 300usec for LXT971A)
1745 CONFIG_PHY_CMD_DELAY (ppc4xx)
1747 Some PHY like Intel LXT971A need extra delay after
1748 command issued before MII status register can be read
1758 Define a default value for Ethernet address to use
1759 for the respective Ethernet interface, in case this
1760 is not determined automatically.
1765 Define a default value for the IP address to use for
1766 the default Ethernet interface, in case this is not
1767 determined through e.g. bootp.
1768 (Environment variable "ipaddr")
1770 - Server IP address:
1773 Defines a default value for the IP address of a TFTP
1774 server to contact when using the "tftboot" command.
1775 (Environment variable "serverip")
1777 CONFIG_KEEP_SERVERADDR
1779 Keeps the server's MAC address, in the env 'serveraddr'
1780 for passing to bootargs (like Linux's netconsole option)
1782 - Gateway IP address:
1785 Defines a default value for the IP address of the
1786 default router where packets to other networks are
1788 (Environment variable "gatewayip")
1793 Defines a default value for the subnet mask (or
1794 routing prefix) which is used to determine if an IP
1795 address belongs to the local subnet or needs to be
1796 forwarded through a router.
1797 (Environment variable "netmask")
1799 - Multicast TFTP Mode:
1802 Defines whether you want to support multicast TFTP as per
1803 rfc-2090; for example to work with atftp. Lets lots of targets
1804 tftp down the same boot image concurrently. Note: the Ethernet
1805 driver in use must provide a function: mcast() to join/leave a
1808 - BOOTP Recovery Mode:
1809 CONFIG_BOOTP_RANDOM_DELAY
1811 If you have many targets in a network that try to
1812 boot using BOOTP, you may want to avoid that all
1813 systems send out BOOTP requests at precisely the same
1814 moment (which would happen for instance at recovery
1815 from a power failure, when all systems will try to
1816 boot, thus flooding the BOOTP server. Defining
1817 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1818 inserted before sending out BOOTP requests. The
1819 following delays are inserted then:
1821 1st BOOTP request: delay 0 ... 1 sec
1822 2nd BOOTP request: delay 0 ... 2 sec
1823 3rd BOOTP request: delay 0 ... 4 sec
1825 BOOTP requests: delay 0 ... 8 sec
1827 - DHCP Advanced Options:
1828 You can fine tune the DHCP functionality by defining
1829 CONFIG_BOOTP_* symbols:
1831 CONFIG_BOOTP_SUBNETMASK
1832 CONFIG_BOOTP_GATEWAY
1833 CONFIG_BOOTP_HOSTNAME
1834 CONFIG_BOOTP_NISDOMAIN
1835 CONFIG_BOOTP_BOOTPATH
1836 CONFIG_BOOTP_BOOTFILESIZE
1839 CONFIG_BOOTP_SEND_HOSTNAME
1840 CONFIG_BOOTP_NTPSERVER
1841 CONFIG_BOOTP_TIMEOFFSET
1842 CONFIG_BOOTP_VENDOREX
1843 CONFIG_BOOTP_MAY_FAIL
1845 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1846 environment variable, not the BOOTP server.
1848 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1849 after the configured retry count, the call will fail
1850 instead of starting over. This can be used to fail over
1851 to Link-local IP address configuration if the DHCP server
1854 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1855 serverip from a DHCP server, it is possible that more
1856 than one DNS serverip is offered to the client.
1857 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1858 serverip will be stored in the additional environment
1859 variable "dnsip2". The first DNS serverip is always
1860 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1863 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1864 to do a dynamic update of a DNS server. To do this, they
1865 need the hostname of the DHCP requester.
1866 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1867 of the "hostname" environment variable is passed as
1868 option 12 to the DHCP server.
1870 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1872 A 32bit value in microseconds for a delay between
1873 receiving a "DHCP Offer" and sending the "DHCP Request".
1874 This fixes a problem with certain DHCP servers that don't
1875 respond 100% of the time to a "DHCP request". E.g. On an
1876 AT91RM9200 processor running at 180MHz, this delay needed
1877 to be *at least* 15,000 usec before a Windows Server 2003
1878 DHCP server would reply 100% of the time. I recommend at
1879 least 50,000 usec to be safe. The alternative is to hope
1880 that one of the retries will be successful but note that
1881 the DHCP timeout and retry process takes a longer than
1884 - Link-local IP address negotiation:
1885 Negotiate with other link-local clients on the local network
1886 for an address that doesn't require explicit configuration.
1887 This is especially useful if a DHCP server cannot be guaranteed
1888 to exist in all environments that the device must operate.
1890 See doc/README.link-local for more information.
1893 CONFIG_CDP_DEVICE_ID
1895 The device id used in CDP trigger frames.
1897 CONFIG_CDP_DEVICE_ID_PREFIX
1899 A two character string which is prefixed to the MAC address
1904 A printf format string which contains the ascii name of
1905 the port. Normally is set to "eth%d" which sets
1906 eth0 for the first Ethernet, eth1 for the second etc.
1908 CONFIG_CDP_CAPABILITIES
1910 A 32bit integer which indicates the device capabilities;
1911 0x00000010 for a normal host which does not forwards.
1915 An ascii string containing the version of the software.
1919 An ascii string containing the name of the platform.
1923 A 32bit integer sent on the trigger.
1925 CONFIG_CDP_POWER_CONSUMPTION
1927 A 16bit integer containing the power consumption of the
1928 device in .1 of milliwatts.
1930 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1932 A byte containing the id of the VLAN.
1934 - Status LED: CONFIG_STATUS_LED
1936 Several configurations allow to display the current
1937 status using a LED. For instance, the LED will blink
1938 fast while running U-Boot code, stop blinking as
1939 soon as a reply to a BOOTP request was received, and
1940 start blinking slow once the Linux kernel is running
1941 (supported by a status LED driver in the Linux
1942 kernel). Defining CONFIG_STATUS_LED enables this
1945 - CAN Support: CONFIG_CAN_DRIVER
1947 Defining CONFIG_CAN_DRIVER enables CAN driver support
1948 on those systems that support this (optional)
1949 feature, like the TQM8xxL modules.
1951 - I2C Support: CONFIG_SYS_I2C
1953 This enable the NEW i2c subsystem, and will allow you to use
1954 i2c commands at the u-boot command line (as long as you set
1955 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1956 based realtime clock chips or other i2c devices. See
1957 common/cmd_i2c.c for a description of the command line
1960 ported i2c driver to the new framework:
1961 - drivers/i2c/soft_i2c.c:
1962 - activate first bus with CONFIG_SYS_I2C_SOFT define
1963 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1964 for defining speed and slave address
1965 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1966 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1967 for defining speed and slave address
1968 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1969 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1970 for defining speed and slave address
1971 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1972 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1973 for defining speed and slave address
1975 - drivers/i2c/fsl_i2c.c:
1976 - activate i2c driver with CONFIG_SYS_I2C_FSL
1977 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1978 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1979 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1981 - If your board supports a second fsl i2c bus, define
1982 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1983 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1984 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1987 - drivers/i2c/tegra_i2c.c:
1988 - activate this driver with CONFIG_SYS_I2C_TEGRA
1989 - This driver adds 4 i2c buses with a fix speed from
1990 100000 and the slave addr 0!
1992 - drivers/i2c/ppc4xx_i2c.c
1993 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1994 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1995 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1999 CONFIG_SYS_NUM_I2C_BUSES
2000 Hold the number of i2c busses you want to use. If you
2001 don't use/have i2c muxes on your i2c bus, this
2002 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2005 CONFIG_SYS_I2C_DIRECT_BUS
2006 define this, if you don't use i2c muxes on your hardware.
2007 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2010 CONFIG_SYS_I2C_MAX_HOPS
2011 define how many muxes are maximal consecutively connected
2012 on one i2c bus. If you not use i2c muxes, omit this
2015 CONFIG_SYS_I2C_BUSES
2016 hold a list of busses you want to use, only used if
2017 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2018 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2019 CONFIG_SYS_NUM_I2C_BUSES = 9:
2021 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2022 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2023 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2024 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2025 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2026 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2027 {1, {I2C_NULL_HOP}}, \
2028 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2029 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2033 bus 0 on adapter 0 without a mux
2034 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2035 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2036 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2037 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2038 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2039 bus 6 on adapter 1 without a mux
2040 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2041 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2043 If you do not have i2c muxes on your board, omit this define.
2045 - Legacy I2C Support: CONFIG_HARD_I2C
2047 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2048 provides the following compelling advantages:
2050 - more than one i2c adapter is usable
2051 - approved multibus support
2052 - better i2c mux support
2054 ** Please consider updating your I2C driver now. **
2056 These enable legacy I2C serial bus commands. Defining
2057 CONFIG_HARD_I2C will include the appropriate I2C driver
2058 for the selected CPU.
2060 This will allow you to use i2c commands at the u-boot
2061 command line (as long as you set CONFIG_CMD_I2C in
2062 CONFIG_COMMANDS) and communicate with i2c based realtime
2063 clock chips. See common/cmd_i2c.c for a description of the
2064 command line interface.
2066 CONFIG_HARD_I2C selects a hardware I2C controller.
2068 There are several other quantities that must also be
2069 defined when you define CONFIG_HARD_I2C.
2071 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2072 to be the frequency (in Hz) at which you wish your i2c bus
2073 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2074 the CPU's i2c node address).
2076 Now, the u-boot i2c code for the mpc8xx
2077 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2078 and so its address should therefore be cleared to 0 (See,
2079 eg, MPC823e User's Manual p.16-473). So, set
2080 CONFIG_SYS_I2C_SLAVE to 0.
2082 CONFIG_SYS_I2C_INIT_MPC5XXX
2084 When a board is reset during an i2c bus transfer
2085 chips might think that the current transfer is still
2086 in progress. Reset the slave devices by sending start
2087 commands until the slave device responds.
2089 That's all that's required for CONFIG_HARD_I2C.
2091 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2092 then the following macros need to be defined (examples are
2093 from include/configs/lwmon.h):
2097 (Optional). Any commands necessary to enable the I2C
2098 controller or configure ports.
2100 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2104 (Only for MPC8260 CPU). The I/O port to use (the code
2105 assumes both bits are on the same port). Valid values
2106 are 0..3 for ports A..D.
2110 The code necessary to make the I2C data line active
2111 (driven). If the data line is open collector, this
2114 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2118 The code necessary to make the I2C data line tri-stated
2119 (inactive). If the data line is open collector, this
2122 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2126 Code that returns true if the I2C data line is high,
2129 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2133 If <bit> is true, sets the I2C data line high. If it
2134 is false, it clears it (low).
2136 eg: #define I2C_SDA(bit) \
2137 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2138 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2142 If <bit> is true, sets the I2C clock line high. If it
2143 is false, it clears it (low).
2145 eg: #define I2C_SCL(bit) \
2146 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2147 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2151 This delay is invoked four times per clock cycle so this
2152 controls the rate of data transfer. The data rate thus
2153 is 1 / (I2C_DELAY * 4). Often defined to be something
2156 #define I2C_DELAY udelay(2)
2158 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2160 If your arch supports the generic GPIO framework (asm/gpio.h),
2161 then you may alternatively define the two GPIOs that are to be
2162 used as SCL / SDA. Any of the previous I2C_xxx macros will
2163 have GPIO-based defaults assigned to them as appropriate.
2165 You should define these to the GPIO value as given directly to
2166 the generic GPIO functions.
2168 CONFIG_SYS_I2C_INIT_BOARD
2170 When a board is reset during an i2c bus transfer
2171 chips might think that the current transfer is still
2172 in progress. On some boards it is possible to access
2173 the i2c SCLK line directly, either by using the
2174 processor pin as a GPIO or by having a second pin
2175 connected to the bus. If this option is defined a
2176 custom i2c_init_board() routine in boards/xxx/board.c
2177 is run early in the boot sequence.
2179 CONFIG_SYS_I2C_BOARD_LATE_INIT
2181 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2182 defined a custom i2c_board_late_init() routine in
2183 boards/xxx/board.c is run AFTER the operations in i2c_init()
2184 is completed. This callpoint can be used to unreset i2c bus
2185 using CPU i2c controller register accesses for CPUs whose i2c
2186 controller provide such a method. It is called at the end of
2187 i2c_init() to allow i2c_init operations to setup the i2c bus
2188 controller on the CPU (e.g. setting bus speed & slave address).
2190 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2192 This option enables configuration of bi_iic_fast[] flags
2193 in u-boot bd_info structure based on u-boot environment
2194 variable "i2cfast". (see also i2cfast)
2196 CONFIG_I2C_MULTI_BUS
2198 This option allows the use of multiple I2C buses, each of which
2199 must have a controller. At any point in time, only one bus is
2200 active. To switch to a different bus, use the 'i2c dev' command.
2201 Note that bus numbering is zero-based.
2203 CONFIG_SYS_I2C_NOPROBES
2205 This option specifies a list of I2C devices that will be skipped
2206 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2207 is set, specify a list of bus-device pairs. Otherwise, specify
2208 a 1D array of device addresses
2211 #undef CONFIG_I2C_MULTI_BUS
2212 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2214 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2216 #define CONFIG_I2C_MULTI_BUS
2217 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2219 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2221 CONFIG_SYS_SPD_BUS_NUM
2223 If defined, then this indicates the I2C bus number for DDR SPD.
2224 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2226 CONFIG_SYS_RTC_BUS_NUM
2228 If defined, then this indicates the I2C bus number for the RTC.
2229 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2231 CONFIG_SYS_DTT_BUS_NUM
2233 If defined, then this indicates the I2C bus number for the DTT.
2234 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2236 CONFIG_SYS_I2C_DTT_ADDR:
2238 If defined, specifies the I2C address of the DTT device.
2239 If not defined, then U-Boot uses predefined value for
2240 specified DTT device.
2242 CONFIG_SOFT_I2C_READ_REPEATED_START
2244 defining this will force the i2c_read() function in
2245 the soft_i2c driver to perform an I2C repeated start
2246 between writing the address pointer and reading the
2247 data. If this define is omitted the default behaviour
2248 of doing a stop-start sequence will be used. Most I2C
2249 devices can use either method, but some require one or
2252 - SPI Support: CONFIG_SPI
2254 Enables SPI driver (so far only tested with
2255 SPI EEPROM, also an instance works with Crystal A/D and
2256 D/As on the SACSng board)
2260 Enables the driver for SPI controller on SuperH. Currently
2261 only SH7757 is supported.
2265 Enables extended (16-bit) SPI EEPROM addressing.
2266 (symmetrical to CONFIG_I2C_X)
2270 Enables a software (bit-bang) SPI driver rather than
2271 using hardware support. This is a general purpose
2272 driver that only requires three general I/O port pins
2273 (two outputs, one input) to function. If this is
2274 defined, the board configuration must define several
2275 SPI configuration items (port pins to use, etc). For
2276 an example, see include/configs/sacsng.h.
2280 Enables a hardware SPI driver for general-purpose reads
2281 and writes. As with CONFIG_SOFT_SPI, the board configuration
2282 must define a list of chip-select function pointers.
2283 Currently supported on some MPC8xxx processors. For an
2284 example, see include/configs/mpc8349emds.h.
2288 Enables the driver for the SPI controllers on i.MX and MXC
2289 SoCs. Currently i.MX31/35/51 are supported.
2291 - FPGA Support: CONFIG_FPGA
2293 Enables FPGA subsystem.
2295 CONFIG_FPGA_<vendor>
2297 Enables support for specific chip vendors.
2300 CONFIG_FPGA_<family>
2302 Enables support for FPGA family.
2303 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2307 Specify the number of FPGA devices to support.
2309 CONFIG_SYS_FPGA_PROG_FEEDBACK
2311 Enable printing of hash marks during FPGA configuration.
2313 CONFIG_SYS_FPGA_CHECK_BUSY
2315 Enable checks on FPGA configuration interface busy
2316 status by the configuration function. This option
2317 will require a board or device specific function to
2322 If defined, a function that provides delays in the FPGA
2323 configuration driver.
2325 CONFIG_SYS_FPGA_CHECK_CTRLC
2326 Allow Control-C to interrupt FPGA configuration
2328 CONFIG_SYS_FPGA_CHECK_ERROR
2330 Check for configuration errors during FPGA bitfile
2331 loading. For example, abort during Virtex II
2332 configuration if the INIT_B line goes low (which
2333 indicated a CRC error).
2335 CONFIG_SYS_FPGA_WAIT_INIT
2337 Maximum time to wait for the INIT_B line to deassert
2338 after PROB_B has been deasserted during a Virtex II
2339 FPGA configuration sequence. The default time is 500
2342 CONFIG_SYS_FPGA_WAIT_BUSY
2344 Maximum time to wait for BUSY to deassert during
2345 Virtex II FPGA configuration. The default is 5 ms.
2347 CONFIG_SYS_FPGA_WAIT_CONFIG
2349 Time to wait after FPGA configuration. The default is
2352 - Configuration Management:
2355 If defined, this string will be added to the U-Boot
2356 version information (U_BOOT_VERSION)
2358 - Vendor Parameter Protection:
2360 U-Boot considers the values of the environment
2361 variables "serial#" (Board Serial Number) and
2362 "ethaddr" (Ethernet Address) to be parameters that
2363 are set once by the board vendor / manufacturer, and
2364 protects these variables from casual modification by
2365 the user. Once set, these variables are read-only,
2366 and write or delete attempts are rejected. You can
2367 change this behaviour:
2369 If CONFIG_ENV_OVERWRITE is #defined in your config
2370 file, the write protection for vendor parameters is
2371 completely disabled. Anybody can change or delete
2374 Alternatively, if you #define _both_ CONFIG_ETHADDR
2375 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2376 Ethernet address is installed in the environment,
2377 which can be changed exactly ONCE by the user. [The
2378 serial# is unaffected by this, i. e. it remains
2381 The same can be accomplished in a more flexible way
2382 for any variable by configuring the type of access
2383 to allow for those variables in the ".flags" variable
2384 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2389 Define this variable to enable the reservation of
2390 "protected RAM", i. e. RAM which is not overwritten
2391 by U-Boot. Define CONFIG_PRAM to hold the number of
2392 kB you want to reserve for pRAM. You can overwrite
2393 this default value by defining an environment
2394 variable "pram" to the number of kB you want to
2395 reserve. Note that the board info structure will
2396 still show the full amount of RAM. If pRAM is
2397 reserved, a new environment variable "mem" will
2398 automatically be defined to hold the amount of
2399 remaining RAM in a form that can be passed as boot
2400 argument to Linux, for instance like that:
2402 setenv bootargs ... mem=\${mem}
2405 This way you can tell Linux not to use this memory,
2406 either, which results in a memory region that will
2407 not be affected by reboots.
2409 *WARNING* If your board configuration uses automatic
2410 detection of the RAM size, you must make sure that
2411 this memory test is non-destructive. So far, the
2412 following board configurations are known to be
2415 IVMS8, IVML24, SPD8xx, TQM8xxL,
2416 HERMES, IP860, RPXlite, LWMON,
2419 - Access to physical memory region (> 4GB)
2420 Some basic support is provided for operations on memory not
2421 normally accessible to U-Boot - e.g. some architectures
2422 support access to more than 4GB of memory on 32-bit
2423 machines using physical address extension or similar.
2424 Define CONFIG_PHYSMEM to access this basic support, which
2425 currently only supports clearing the memory.
2430 Define this variable to stop the system in case of a
2431 fatal error, so that you have to reset it manually.
2432 This is probably NOT a good idea for an embedded
2433 system where you want the system to reboot
2434 automatically as fast as possible, but it may be
2435 useful during development since you can try to debug
2436 the conditions that lead to the situation.
2438 CONFIG_NET_RETRY_COUNT
2440 This variable defines the number of retries for
2441 network operations like ARP, RARP, TFTP, or BOOTP
2442 before giving up the operation. If not defined, a
2443 default value of 5 is used.
2447 Timeout waiting for an ARP reply in milliseconds.
2451 Timeout in milliseconds used in NFS protocol.
2452 If you encounter "ERROR: Cannot umount" in nfs command,
2453 try longer timeout such as
2454 #define CONFIG_NFS_TIMEOUT 10000UL
2456 - Command Interpreter:
2457 CONFIG_AUTO_COMPLETE
2459 Enable auto completion of commands using TAB.
2461 Note that this feature has NOT been implemented yet
2462 for the "hush" shell.
2465 CONFIG_SYS_HUSH_PARSER
2467 Define this variable to enable the "hush" shell (from
2468 Busybox) as command line interpreter, thus enabling
2469 powerful command line syntax like
2470 if...then...else...fi conditionals or `&&' and '||'
2471 constructs ("shell scripts").
2473 If undefined, you get the old, much simpler behaviour
2474 with a somewhat smaller memory footprint.
2477 CONFIG_SYS_PROMPT_HUSH_PS2
2479 This defines the secondary prompt string, which is
2480 printed when the command interpreter needs more input
2481 to complete a command. Usually "> ".
2485 In the current implementation, the local variables
2486 space and global environment variables space are
2487 separated. Local variables are those you define by
2488 simply typing `name=value'. To access a local
2489 variable later on, you have write `$name' or
2490 `${name}'; to execute the contents of a variable
2491 directly type `$name' at the command prompt.
2493 Global environment variables are those you use
2494 setenv/printenv to work with. To run a command stored
2495 in such a variable, you need to use the run command,
2496 and you must not use the '$' sign to access them.
2498 To store commands and special characters in a
2499 variable, please use double quotation marks
2500 surrounding the whole text of the variable, instead
2501 of the backslashes before semicolons and special
2504 - Commandline Editing and History:
2505 CONFIG_CMDLINE_EDITING
2507 Enable editing and History functions for interactive
2508 commandline input operations
2510 - Default Environment:
2511 CONFIG_EXTRA_ENV_SETTINGS
2513 Define this to contain any number of null terminated
2514 strings (variable = value pairs) that will be part of
2515 the default environment compiled into the boot image.
2517 For example, place something like this in your
2518 board's config file:
2520 #define CONFIG_EXTRA_ENV_SETTINGS \
2524 Warning: This method is based on knowledge about the
2525 internal format how the environment is stored by the
2526 U-Boot code. This is NOT an official, exported
2527 interface! Although it is unlikely that this format
2528 will change soon, there is no guarantee either.
2529 You better know what you are doing here.
2531 Note: overly (ab)use of the default environment is
2532 discouraged. Make sure to check other ways to preset
2533 the environment like the "source" command or the
2536 CONFIG_ENV_VARS_UBOOT_CONFIG
2538 Define this in order to add variables describing the
2539 U-Boot build configuration to the default environment.
2540 These will be named arch, cpu, board, vendor, and soc.
2542 Enabling this option will cause the following to be defined:
2550 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2552 Define this in order to add variables describing certain
2553 run-time determined information about the hardware to the
2554 environment. These will be named board_name, board_rev.
2556 CONFIG_DELAY_ENVIRONMENT
2558 Normally the environment is loaded when the board is
2559 intialised so that it is available to U-Boot. This inhibits
2560 that so that the environment is not available until
2561 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2562 this is instead controlled by the value of
2563 /config/load-environment.
2565 - DataFlash Support:
2566 CONFIG_HAS_DATAFLASH
2568 Defining this option enables DataFlash features and
2569 allows to read/write in Dataflash via the standard
2572 - Serial Flash support
2575 Defining this option enables SPI flash commands
2576 'sf probe/read/write/erase/update'.
2578 Usage requires an initial 'probe' to define the serial
2579 flash parameters, followed by read/write/erase/update
2582 The following defaults may be provided by the platform
2583 to handle the common case when only a single serial
2584 flash is present on the system.
2586 CONFIG_SF_DEFAULT_BUS Bus identifier
2587 CONFIG_SF_DEFAULT_CS Chip-select
2588 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2589 CONFIG_SF_DEFAULT_SPEED in Hz
2593 Define this option to include a destructive SPI flash
2596 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2598 Define this option to use the Bank addr/Extended addr
2599 support on SPI flashes which has size > 16Mbytes.
2601 - SystemACE Support:
2604 Adding this option adds support for Xilinx SystemACE
2605 chips attached via some sort of local bus. The address
2606 of the chip must also be defined in the
2607 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2609 #define CONFIG_SYSTEMACE
2610 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2612 When SystemACE support is added, the "ace" device type
2613 becomes available to the fat commands, i.e. fatls.
2615 - TFTP Fixed UDP Port:
2618 If this is defined, the environment variable tftpsrcp
2619 is used to supply the TFTP UDP source port value.
2620 If tftpsrcp isn't defined, the normal pseudo-random port
2621 number generator is used.
2623 Also, the environment variable tftpdstp is used to supply
2624 the TFTP UDP destination port value. If tftpdstp isn't
2625 defined, the normal port 69 is used.
2627 The purpose for tftpsrcp is to allow a TFTP server to
2628 blindly start the TFTP transfer using the pre-configured
2629 target IP address and UDP port. This has the effect of
2630 "punching through" the (Windows XP) firewall, allowing
2631 the remainder of the TFTP transfer to proceed normally.
2632 A better solution is to properly configure the firewall,
2633 but sometimes that is not allowed.
2638 This enables a generic 'hash' command which can produce
2639 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2643 Enable the hash verify command (hash -v). This adds to code
2646 CONFIG_SHA1 - support SHA1 hashing
2647 CONFIG_SHA256 - support SHA256 hashing
2649 Note: There is also a sha1sum command, which should perhaps
2650 be deprecated in favour of 'hash sha1'.
2652 - Freescale i.MX specific commands:
2653 CONFIG_CMD_HDMIDETECT
2654 This enables 'hdmidet' command which returns true if an
2655 HDMI monitor is detected. This command is i.MX 6 specific.
2658 This enables the 'bmode' (bootmode) command for forcing
2659 a boot from specific media.
2661 This is useful for forcing the ROM's usb downloader to
2662 activate upon a watchdog reset which is nice when iterating
2663 on U-Boot. Using the reset button or running bmode normal
2664 will set it back to normal. This command currently
2665 supports i.MX53 and i.MX6.
2670 This enables the RSA algorithm used for FIT image verification
2671 in U-Boot. See doc/uImage/signature for more information.
2673 The signing part is build into mkimage regardless of this
2677 - Show boot progress:
2678 CONFIG_SHOW_BOOT_PROGRESS
2680 Defining this option allows to add some board-
2681 specific code (calling a user-provided function
2682 "show_boot_progress(int)") that enables you to show
2683 the system's boot progress on some display (for
2684 example, some LED's) on your board. At the moment,
2685 the following checkpoints are implemented:
2687 - Detailed boot stage timing
2689 Define this option to get detailed timing of each stage
2690 of the boot process.
2692 CONFIG_BOOTSTAGE_USER_COUNT
2693 This is the number of available user bootstage records.
2694 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2695 a new ID will be allocated from this stash. If you exceed
2696 the limit, recording will stop.
2698 CONFIG_BOOTSTAGE_REPORT
2699 Define this to print a report before boot, similar to this:
2701 Timer summary in microseconds:
2704 3,575,678 3,575,678 board_init_f start
2705 3,575,695 17 arch_cpu_init A9
2706 3,575,777 82 arch_cpu_init done
2707 3,659,598 83,821 board_init_r start
2708 3,910,375 250,777 main_loop
2709 29,916,167 26,005,792 bootm_start
2710 30,361,327 445,160 start_kernel
2712 CONFIG_CMD_BOOTSTAGE
2713 Add a 'bootstage' command which supports printing a report
2714 and un/stashing of bootstage data.
2716 CONFIG_BOOTSTAGE_FDT
2717 Stash the bootstage information in the FDT. A root 'bootstage'
2718 node is created with each bootstage id as a child. Each child
2719 has a 'name' property and either 'mark' containing the
2720 mark time in microsecond, or 'accum' containing the
2721 accumulated time for that bootstage id in microseconds.
2726 name = "board_init_f";
2735 Code in the Linux kernel can find this in /proc/devicetree.
2737 Legacy uImage format:
2740 1 common/cmd_bootm.c before attempting to boot an image
2741 -1 common/cmd_bootm.c Image header has bad magic number
2742 2 common/cmd_bootm.c Image header has correct magic number
2743 -2 common/cmd_bootm.c Image header has bad checksum
2744 3 common/cmd_bootm.c Image header has correct checksum
2745 -3 common/cmd_bootm.c Image data has bad checksum
2746 4 common/cmd_bootm.c Image data has correct checksum
2747 -4 common/cmd_bootm.c Image is for unsupported architecture
2748 5 common/cmd_bootm.c Architecture check OK
2749 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2750 6 common/cmd_bootm.c Image Type check OK
2751 -6 common/cmd_bootm.c gunzip uncompression error
2752 -7 common/cmd_bootm.c Unimplemented compression type
2753 7 common/cmd_bootm.c Uncompression OK
2754 8 common/cmd_bootm.c No uncompress/copy overwrite error
2755 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2757 9 common/image.c Start initial ramdisk verification
2758 -10 common/image.c Ramdisk header has bad magic number
2759 -11 common/image.c Ramdisk header has bad checksum
2760 10 common/image.c Ramdisk header is OK
2761 -12 common/image.c Ramdisk data has bad checksum
2762 11 common/image.c Ramdisk data has correct checksum
2763 12 common/image.c Ramdisk verification complete, start loading
2764 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2765 13 common/image.c Start multifile image verification
2766 14 common/image.c No initial ramdisk, no multifile, continue.
2768 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2770 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2771 -31 post/post.c POST test failed, detected by post_output_backlog()
2772 -32 post/post.c POST test failed, detected by post_run_single()
2774 34 common/cmd_doc.c before loading a Image from a DOC device
2775 -35 common/cmd_doc.c Bad usage of "doc" command
2776 35 common/cmd_doc.c correct usage of "doc" command
2777 -36 common/cmd_doc.c No boot device
2778 36 common/cmd_doc.c correct boot device
2779 -37 common/cmd_doc.c Unknown Chip ID on boot device
2780 37 common/cmd_doc.c correct chip ID found, device available
2781 -38 common/cmd_doc.c Read Error on boot device
2782 38 common/cmd_doc.c reading Image header from DOC device OK
2783 -39 common/cmd_doc.c Image header has bad magic number
2784 39 common/cmd_doc.c Image header has correct magic number
2785 -40 common/cmd_doc.c Error reading Image from DOC device
2786 40 common/cmd_doc.c Image header has correct magic number
2787 41 common/cmd_ide.c before loading a Image from a IDE device
2788 -42 common/cmd_ide.c Bad usage of "ide" command
2789 42 common/cmd_ide.c correct usage of "ide" command
2790 -43 common/cmd_ide.c No boot device
2791 43 common/cmd_ide.c boot device found
2792 -44 common/cmd_ide.c Device not available
2793 44 common/cmd_ide.c Device available
2794 -45 common/cmd_ide.c wrong partition selected
2795 45 common/cmd_ide.c partition selected
2796 -46 common/cmd_ide.c Unknown partition table
2797 46 common/cmd_ide.c valid partition table found
2798 -47 common/cmd_ide.c Invalid partition type
2799 47 common/cmd_ide.c correct partition type
2800 -48 common/cmd_ide.c Error reading Image Header on boot device
2801 48 common/cmd_ide.c reading Image Header from IDE device OK
2802 -49 common/cmd_ide.c Image header has bad magic number
2803 49 common/cmd_ide.c Image header has correct magic number
2804 -50 common/cmd_ide.c Image header has bad checksum
2805 50 common/cmd_ide.c Image header has correct checksum
2806 -51 common/cmd_ide.c Error reading Image from IDE device
2807 51 common/cmd_ide.c reading Image from IDE device OK
2808 52 common/cmd_nand.c before loading a Image from a NAND device
2809 -53 common/cmd_nand.c Bad usage of "nand" command
2810 53 common/cmd_nand.c correct usage of "nand" command
2811 -54 common/cmd_nand.c No boot device
2812 54 common/cmd_nand.c boot device found
2813 -55 common/cmd_nand.c Unknown Chip ID on boot device
2814 55 common/cmd_nand.c correct chip ID found, device available
2815 -56 common/cmd_nand.c Error reading Image Header on boot device
2816 56 common/cmd_nand.c reading Image Header from NAND device OK
2817 -57 common/cmd_nand.c Image header has bad magic number
2818 57 common/cmd_nand.c Image header has correct magic number
2819 -58 common/cmd_nand.c Error reading Image from NAND device
2820 58 common/cmd_nand.c reading Image from NAND device OK
2822 -60 common/env_common.c Environment has a bad CRC, using default
2824 64 net/eth.c starting with Ethernet configuration.
2825 -64 net/eth.c no Ethernet found.
2826 65 net/eth.c Ethernet found.
2828 -80 common/cmd_net.c usage wrong
2829 80 common/cmd_net.c before calling NetLoop()
2830 -81 common/cmd_net.c some error in NetLoop() occurred
2831 81 common/cmd_net.c NetLoop() back without error
2832 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2833 82 common/cmd_net.c trying automatic boot
2834 83 common/cmd_net.c running "source" command
2835 -83 common/cmd_net.c some error in automatic boot or "source" command
2836 84 common/cmd_net.c end without errors
2841 100 common/cmd_bootm.c Kernel FIT Image has correct format
2842 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2843 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2844 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2845 102 common/cmd_bootm.c Kernel unit name specified
2846 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2847 103 common/cmd_bootm.c Found configuration node
2848 104 common/cmd_bootm.c Got kernel subimage node offset
2849 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2850 105 common/cmd_bootm.c Kernel subimage hash verification OK
2851 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2852 106 common/cmd_bootm.c Architecture check OK
2853 -106 common/cmd_bootm.c Kernel subimage has wrong type
2854 107 common/cmd_bootm.c Kernel subimage type OK
2855 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2856 108 common/cmd_bootm.c Got kernel subimage data/size
2857 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2858 -109 common/cmd_bootm.c Can't get kernel subimage type
2859 -110 common/cmd_bootm.c Can't get kernel subimage comp
2860 -111 common/cmd_bootm.c Can't get kernel subimage os
2861 -112 common/cmd_bootm.c Can't get kernel subimage load address
2862 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2864 120 common/image.c Start initial ramdisk verification
2865 -120 common/image.c Ramdisk FIT image has incorrect format
2866 121 common/image.c Ramdisk FIT image has correct format
2867 122 common/image.c No ramdisk subimage unit name, using configuration
2868 -122 common/image.c Can't get configuration for ramdisk subimage
2869 123 common/image.c Ramdisk unit name specified
2870 -124 common/image.c Can't get ramdisk subimage node offset
2871 125 common/image.c Got ramdisk subimage node offset
2872 -125 common/image.c Ramdisk subimage hash verification failed
2873 126 common/image.c Ramdisk subimage hash verification OK
2874 -126 common/image.c Ramdisk subimage for unsupported architecture
2875 127 common/image.c Architecture check OK
2876 -127 common/image.c Can't get ramdisk subimage data/size
2877 128 common/image.c Got ramdisk subimage data/size
2878 129 common/image.c Can't get ramdisk load address
2879 -129 common/image.c Got ramdisk load address
2881 -130 common/cmd_doc.c Incorrect FIT image format
2882 131 common/cmd_doc.c FIT image format OK
2884 -140 common/cmd_ide.c Incorrect FIT image format
2885 141 common/cmd_ide.c FIT image format OK
2887 -150 common/cmd_nand.c Incorrect FIT image format
2888 151 common/cmd_nand.c FIT image format OK
2890 - FIT image support:
2892 Enable support for the FIT uImage format.
2894 CONFIG_FIT_BEST_MATCH
2895 When no configuration is explicitly selected, default to the
2896 one whose fdt's compatibility field best matches that of
2897 U-Boot itself. A match is considered "best" if it matches the
2898 most specific compatibility entry of U-Boot's fdt's root node.
2899 The order of entries in the configuration's fdt is ignored.
2901 CONFIG_FIT_SIGNATURE
2902 This option enables signature verification of FIT uImages,
2903 using a hash signed and verified using RSA. See
2904 doc/uImage.FIT/signature.txt for more details.
2906 - Standalone program support:
2907 CONFIG_STANDALONE_LOAD_ADDR
2909 This option defines a board specific value for the
2910 address where standalone program gets loaded, thus
2911 overwriting the architecture dependent default
2914 - Frame Buffer Address:
2917 Define CONFIG_FB_ADDR if you want to use specific
2918 address for frame buffer. This is typically the case
2919 when using a graphics controller has separate video
2920 memory. U-Boot will then place the frame buffer at
2921 the given address instead of dynamically reserving it
2922 in system RAM by calling lcd_setmem(), which grabs
2923 the memory for the frame buffer depending on the
2924 configured panel size.
2926 Please see board_init_f function.
2928 - Automatic software updates via TFTP server
2930 CONFIG_UPDATE_TFTP_CNT_MAX
2931 CONFIG_UPDATE_TFTP_MSEC_MAX
2933 These options enable and control the auto-update feature;
2934 for a more detailed description refer to doc/README.update.
2936 - MTD Support (mtdparts command, UBI support)
2939 Adds the MTD device infrastructure from the Linux kernel.
2940 Needed for mtdparts command support.
2942 CONFIG_MTD_PARTITIONS
2944 Adds the MTD partitioning infrastructure from the Linux
2945 kernel. Needed for UBI support.
2950 Adds commands for interacting with MTD partitions formatted
2951 with the UBI flash translation layer
2953 Requires also defining CONFIG_RBTREE
2955 CONFIG_UBI_SILENCE_MSG
2957 Make the verbose messages from UBI stop printing. This leaves
2958 warnings and errors enabled.
2963 Adds commands for interacting with UBI volumes formatted as
2964 UBIFS. UBIFS is read-only in u-boot.
2966 Requires UBI support as well as CONFIG_LZO
2968 CONFIG_UBIFS_SILENCE_MSG
2970 Make the verbose messages from UBIFS stop printing. This leaves
2971 warnings and errors enabled.
2975 Enable building of SPL globally.
2978 LDSCRIPT for linking the SPL binary.
2980 CONFIG_SPL_MAX_FOOTPRINT
2981 Maximum size in memory allocated to the SPL, BSS included.
2982 When defined, the linker checks that the actual memory
2983 used by SPL from _start to __bss_end does not exceed it.
2984 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2985 must not be both defined at the same time.
2988 Maximum size of the SPL image (text, data, rodata, and
2989 linker lists sections), BSS excluded.
2990 When defined, the linker checks that the actual size does
2993 CONFIG_SPL_TEXT_BASE
2994 TEXT_BASE for linking the SPL binary.
2996 CONFIG_SPL_RELOC_TEXT_BASE
2997 Address to relocate to. If unspecified, this is equal to
2998 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
3000 CONFIG_SPL_BSS_START_ADDR
3001 Link address for the BSS within the SPL binary.
3003 CONFIG_SPL_BSS_MAX_SIZE
3004 Maximum size in memory allocated to the SPL BSS.
3005 When defined, the linker checks that the actual memory used
3006 by SPL from __bss_start to __bss_end does not exceed it.
3007 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3008 must not be both defined at the same time.
3011 Adress of the start of the stack SPL will use
3013 CONFIG_SPL_RELOC_STACK
3014 Adress of the start of the stack SPL will use after
3015 relocation. If unspecified, this is equal to
3018 CONFIG_SYS_SPL_MALLOC_START
3019 Starting address of the malloc pool used in SPL.
3021 CONFIG_SYS_SPL_MALLOC_SIZE
3022 The size of the malloc pool used in SPL.
3024 CONFIG_SPL_FRAMEWORK
3025 Enable the SPL framework under common/. This framework
3026 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3027 NAND loading of the Linux Kernel.
3029 CONFIG_SPL_DISPLAY_PRINT
3030 For ARM, enable an optional function to print more information
3031 about the running system.
3033 CONFIG_SPL_INIT_MINIMAL
3034 Arch init code should be built for a very small image
3036 CONFIG_SPL_LIBCOMMON_SUPPORT
3037 Support for common/libcommon.o in SPL binary
3039 CONFIG_SPL_LIBDISK_SUPPORT
3040 Support for disk/libdisk.o in SPL binary
3042 CONFIG_SPL_I2C_SUPPORT
3043 Support for drivers/i2c/libi2c.o in SPL binary
3045 CONFIG_SPL_GPIO_SUPPORT
3046 Support for drivers/gpio/libgpio.o in SPL binary
3048 CONFIG_SPL_MMC_SUPPORT
3049 Support for drivers/mmc/libmmc.o in SPL binary
3051 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3052 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3053 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3054 Address, size and partition on the MMC to load U-Boot from
3055 when the MMC is being used in raw mode.
3057 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3058 Sector to load kernel uImage from when MMC is being
3059 used in raw mode (for Falcon mode)
3061 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3062 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3063 Sector and number of sectors to load kernel argument
3064 parameters from when MMC is being used in raw mode
3067 CONFIG_SPL_FAT_SUPPORT
3068 Support for fs/fat/libfat.o in SPL binary
3070 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3071 Filename to read to load U-Boot when reading from FAT
3073 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3074 Filename to read to load kernel uImage when reading
3075 from FAT (for Falcon mode)
3077 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3078 Filename to read to load kernel argument parameters
3079 when reading from FAT (for Falcon mode)
3081 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3082 Set this for NAND SPL on PPC mpc83xx targets, so that
3083 start.S waits for the rest of the SPL to load before
3084 continuing (the hardware starts execution after just
3085 loading the first page rather than the full 4K).
3087 CONFIG_SPL_NAND_BASE
3088 Include nand_base.c in the SPL. Requires
3089 CONFIG_SPL_NAND_DRIVERS.
3091 CONFIG_SPL_NAND_DRIVERS
3092 SPL uses normal NAND drivers, not minimal drivers.
3095 Include standard software ECC in the SPL
3097 CONFIG_SPL_NAND_SIMPLE
3098 Support for NAND boot using simple NAND drivers that
3099 expose the cmd_ctrl() interface.
3101 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3102 Set for the SPL on PPC mpc8xxx targets, support for
3103 arch/powerpc/cpu/mpc8xxx/ddr/libddr.o in SPL binary.
3105 CONFIG_SPL_COMMON_INIT_DDR
3106 Set for common ddr init with serial presence detect in
3109 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3110 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3111 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3112 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3113 CONFIG_SYS_NAND_ECCBYTES
3114 Defines the size and behavior of the NAND that SPL uses
3117 CONFIG_SYS_NAND_U_BOOT_OFFS
3118 Location in NAND to read U-Boot from
3120 CONFIG_SYS_NAND_U_BOOT_DST
3121 Location in memory to load U-Boot to
3123 CONFIG_SYS_NAND_U_BOOT_SIZE
3124 Size of image to load
3126 CONFIG_SYS_NAND_U_BOOT_START
3127 Entry point in loaded image to jump to
3129 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3130 Define this if you need to first read the OOB and then the
3131 data. This is used for example on davinci plattforms.
3133 CONFIG_SPL_OMAP3_ID_NAND
3134 Support for an OMAP3-specific set of functions to return the
3135 ID and MFR of the first attached NAND chip, if present.
3137 CONFIG_SPL_SERIAL_SUPPORT
3138 Support for drivers/serial/libserial.o in SPL binary
3140 CONFIG_SPL_SPI_FLASH_SUPPORT
3141 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3143 CONFIG_SPL_SPI_SUPPORT
3144 Support for drivers/spi/libspi.o in SPL binary
3146 CONFIG_SPL_RAM_DEVICE
3147 Support for running image already present in ram, in SPL binary
3149 CONFIG_SPL_LIBGENERIC_SUPPORT
3150 Support for lib/libgeneric.o in SPL binary
3152 CONFIG_SPL_ENV_SUPPORT
3153 Support for the environment operating in SPL binary
3155 CONFIG_SPL_NET_SUPPORT
3156 Support for the net/libnet.o in SPL binary.
3157 It conflicts with SPL env from storage medium specified by
3158 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3161 Image offset to which the SPL should be padded before appending
3162 the SPL payload. By default, this is defined as
3163 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3164 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3165 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3168 Final target image containing SPL and payload. Some SPLs
3169 use an arch-specific makefile fragment instead, for
3170 example if more than one image needs to be produced.
3172 CONFIG_FIT_SPL_PRINT
3173 Printing information about a FIT image adds quite a bit of
3174 code to SPL. So this is normally disabled in SPL. Use this
3175 option to re-enable it. This will affect the output of the
3176 bootm command when booting a FIT image.
3180 Enable building of TPL globally.
3183 Image offset to which the TPL should be padded before appending
3184 the TPL payload. By default, this is defined as
3185 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3186 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3187 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3192 [so far only for SMDK2400 boards]
3194 - Modem support enable:
3195 CONFIG_MODEM_SUPPORT
3197 - RTS/CTS Flow control enable:
3200 - Modem debug support:
3201 CONFIG_MODEM_SUPPORT_DEBUG
3203 Enables debugging stuff (char screen[1024], dbg())
3204 for modem support. Useful only with BDI2000.
3206 - Interrupt support (PPC):
3208 There are common interrupt_init() and timer_interrupt()
3209 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3210 for CPU specific initialization. interrupt_init_cpu()
3211 should set decrementer_count to appropriate value. If
3212 CPU resets decrementer automatically after interrupt
3213 (ppc4xx) it should set decrementer_count to zero.
3214 timer_interrupt() calls timer_interrupt_cpu() for CPU
3215 specific handling. If board has watchdog / status_led
3216 / other_activity_monitor it works automatically from
3217 general timer_interrupt().
3221 In the target system modem support is enabled when a
3222 specific key (key combination) is pressed during
3223 power-on. Otherwise U-Boot will boot normally
3224 (autoboot). The key_pressed() function is called from
3225 board_init(). Currently key_pressed() is a dummy
3226 function, returning 1 and thus enabling modem
3229 If there are no modem init strings in the
3230 environment, U-Boot proceed to autoboot; the
3231 previous output (banner, info printfs) will be
3234 See also: doc/README.Modem
3236 Board initialization settings:
3237 ------------------------------
3239 During Initialization u-boot calls a number of board specific functions
3240 to allow the preparation of board specific prerequisites, e.g. pin setup
3241 before drivers are initialized. To enable these callbacks the
3242 following configuration macros have to be defined. Currently this is
3243 architecture specific, so please check arch/your_architecture/lib/board.c
3244 typically in board_init_f() and board_init_r().
3246 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3247 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3248 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3249 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3251 Configuration Settings:
3252 -----------------------
3254 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3255 undefine this when you're short of memory.
3257 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3258 width of the commands listed in the 'help' command output.
3260 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3261 prompt for user input.
3263 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3265 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3267 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3269 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3270 the application (usually a Linux kernel) when it is
3273 - CONFIG_SYS_BAUDRATE_TABLE:
3274 List of legal baudrate settings for this board.
3276 - CONFIG_SYS_CONSOLE_INFO_QUIET
3277 Suppress display of console information at boot.
3279 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3280 If the board specific function
3281 extern int overwrite_console (void);
3282 returns 1, the stdin, stderr and stdout are switched to the
3283 serial port, else the settings in the environment are used.
3285 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3286 Enable the call to overwrite_console().
3288 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3289 Enable overwrite of previous console environment settings.
3291 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3292 Begin and End addresses of the area used by the
3295 - CONFIG_SYS_ALT_MEMTEST:
3296 Enable an alternate, more extensive memory test.
3298 - CONFIG_SYS_MEMTEST_SCRATCH:
3299 Scratch address used by the alternate memory test
3300 You only need to set this if address zero isn't writeable
3302 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3303 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3304 this specified memory area will get subtracted from the top
3305 (end) of RAM and won't get "touched" at all by U-Boot. By
3306 fixing up gd->ram_size the Linux kernel should gets passed
3307 the now "corrected" memory size and won't touch it either.
3308 This should work for arch/ppc and arch/powerpc. Only Linux
3309 board ports in arch/powerpc with bootwrapper support that
3310 recalculate the memory size from the SDRAM controller setup
3311 will have to get fixed in Linux additionally.
3313 This option can be used as a workaround for the 440EPx/GRx
3314 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3317 WARNING: Please make sure that this value is a multiple of
3318 the Linux page size (normally 4k). If this is not the case,
3319 then the end address of the Linux memory will be located at a
3320 non page size aligned address and this could cause major
3323 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3324 Enable temporary baudrate change while serial download
3326 - CONFIG_SYS_SDRAM_BASE:
3327 Physical start address of SDRAM. _Must_ be 0 here.
3329 - CONFIG_SYS_MBIO_BASE:
3330 Physical start address of Motherboard I/O (if using a
3333 - CONFIG_SYS_FLASH_BASE:
3334 Physical start address of Flash memory.
3336 - CONFIG_SYS_MONITOR_BASE:
3337 Physical start address of boot monitor code (set by
3338 make config files to be same as the text base address
3339 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3340 CONFIG_SYS_FLASH_BASE when booting from flash.
3342 - CONFIG_SYS_MONITOR_LEN:
3343 Size of memory reserved for monitor code, used to
3344 determine _at_compile_time_ (!) if the environment is
3345 embedded within the U-Boot image, or in a separate
3348 - CONFIG_SYS_MALLOC_LEN:
3349 Size of DRAM reserved for malloc() use.
3351 - CONFIG_SYS_BOOTM_LEN:
3352 Normally compressed uImages are limited to an
3353 uncompressed size of 8 MBytes. If this is not enough,
3354 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3355 to adjust this setting to your needs.
3357 - CONFIG_SYS_BOOTMAPSZ:
3358 Maximum size of memory mapped by the startup code of
3359 the Linux kernel; all data that must be processed by
3360 the Linux kernel (bd_info, boot arguments, FDT blob if
3361 used) must be put below this limit, unless "bootm_low"
3362 enviroment variable is defined and non-zero. In such case
3363 all data for the Linux kernel must be between "bootm_low"
3364 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3365 variable "bootm_mapsize" will override the value of
3366 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3367 then the value in "bootm_size" will be used instead.
3369 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3370 Enable initrd_high functionality. If defined then the
3371 initrd_high feature is enabled and the bootm ramdisk subcommand
3374 - CONFIG_SYS_BOOT_GET_CMDLINE:
3375 Enables allocating and saving kernel cmdline in space between
3376 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3378 - CONFIG_SYS_BOOT_GET_KBD:
3379 Enables allocating and saving a kernel copy of the bd_info in
3380 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3382 - CONFIG_SYS_MAX_FLASH_BANKS:
3383 Max number of Flash memory banks
3385 - CONFIG_SYS_MAX_FLASH_SECT:
3386 Max number of sectors on a Flash chip
3388 - CONFIG_SYS_FLASH_ERASE_TOUT:
3389 Timeout for Flash erase operations (in ms)
3391 - CONFIG_SYS_FLASH_WRITE_TOUT:
3392 Timeout for Flash write operations (in ms)
3394 - CONFIG_SYS_FLASH_LOCK_TOUT
3395 Timeout for Flash set sector lock bit operation (in ms)
3397 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3398 Timeout for Flash clear lock bits operation (in ms)
3400 - CONFIG_SYS_FLASH_PROTECTION
3401 If defined, hardware flash sectors protection is used
3402 instead of U-Boot software protection.
3404 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3406 Enable TFTP transfers directly to flash memory;
3407 without this option such a download has to be
3408 performed in two steps: (1) download to RAM, and (2)
3409 copy from RAM to flash.
3411 The two-step approach is usually more reliable, since
3412 you can check if the download worked before you erase
3413 the flash, but in some situations (when system RAM is
3414 too limited to allow for a temporary copy of the
3415 downloaded image) this option may be very useful.
3417 - CONFIG_SYS_FLASH_CFI:
3418 Define if the flash driver uses extra elements in the
3419 common flash structure for storing flash geometry.
3421 - CONFIG_FLASH_CFI_DRIVER
3422 This option also enables the building of the cfi_flash driver
3423 in the drivers directory
3425 - CONFIG_FLASH_CFI_MTD
3426 This option enables the building of the cfi_mtd driver
3427 in the drivers directory. The driver exports CFI flash
3430 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3431 Use buffered writes to flash.
3433 - CONFIG_FLASH_SPANSION_S29WS_N
3434 s29ws-n MirrorBit flash has non-standard addresses for buffered
3437 - CONFIG_SYS_FLASH_QUIET_TEST
3438 If this option is defined, the common CFI flash doesn't
3439 print it's warning upon not recognized FLASH banks. This
3440 is useful, if some of the configured banks are only
3441 optionally available.
3443 - CONFIG_FLASH_SHOW_PROGRESS
3444 If defined (must be an integer), print out countdown
3445 digits and dots. Recommended value: 45 (9..1) for 80
3446 column displays, 15 (3..1) for 40 column displays.
3448 - CONFIG_FLASH_VERIFY
3449 If defined, the content of the flash (destination) is compared
3450 against the source after the write operation. An error message
3451 will be printed when the contents are not identical.
3452 Please note that this option is useless in nearly all cases,
3453 since such flash programming errors usually are detected earlier
3454 while unprotecting/erasing/programming. Please only enable
3455 this option if you really know what you are doing.
3457 - CONFIG_SYS_RX_ETH_BUFFER:
3458 Defines the number of Ethernet receive buffers. On some
3459 Ethernet controllers it is recommended to set this value
3460 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3461 buffers can be full shortly after enabling the interface
3462 on high Ethernet traffic.
3463 Defaults to 4 if not defined.
3465 - CONFIG_ENV_MAX_ENTRIES
3467 Maximum number of entries in the hash table that is used
3468 internally to store the environment settings. The default
3469 setting is supposed to be generous and should work in most
3470 cases. This setting can be used to tune behaviour; see
3471 lib/hashtable.c for details.
3473 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3474 - CONFIG_ENV_FLAGS_LIST_STATIC
3475 Enable validation of the values given to enviroment variables when
3476 calling env set. Variables can be restricted to only decimal,
3477 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3478 the variables can also be restricted to IP address or MAC address.
3480 The format of the list is:
3481 type_attribute = [s|d|x|b|i|m]
3482 access_atribute = [a|r|o|c]
3483 attributes = type_attribute[access_atribute]
3484 entry = variable_name[:attributes]
3487 The type attributes are:
3488 s - String (default)
3491 b - Boolean ([1yYtT|0nNfF])
3495 The access attributes are:
3501 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3502 Define this to a list (string) to define the ".flags"
3503 envirnoment variable in the default or embedded environment.
3505 - CONFIG_ENV_FLAGS_LIST_STATIC
3506 Define this to a list (string) to define validation that
3507 should be done if an entry is not found in the ".flags"
3508 environment variable. To override a setting in the static
3509 list, simply add an entry for the same variable name to the
3512 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3513 If defined, don't allow the -f switch to env set override variable
3516 - CONFIG_SYS_GENERIC_BOARD
3517 This selects the architecture-generic board system instead of the
3518 architecture-specific board files. It is intended to move boards
3519 to this new framework over time. Defining this will disable the
3520 arch/foo/lib/board.c file and use common/board_f.c and
3521 common/board_r.c instead. To use this option your architecture
3522 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3523 its config.mk file). If you find problems enabling this option on
3524 your board please report the problem and send patches!
3526 - CONFIG_SYS_SYM_OFFSETS
3527 This is set by architectures that use offsets for link symbols
3528 instead of absolute values. So bss_start is obtained using an
3529 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3530 directly. You should not need to touch this setting.
3532 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3533 This is set by OMAP boards for the max time that reset should
3534 be asserted. See doc/README.omap-reset-time for details on how
3535 the value can be calulated on a given board.
3537 The following definitions that deal with the placement and management
3538 of environment data (variable area); in general, we support the
3539 following configurations:
3541 - CONFIG_BUILD_ENVCRC:
3543 Builds up envcrc with the target environment so that external utils
3544 may easily extract it and embed it in final U-Boot images.
3546 - CONFIG_ENV_IS_IN_FLASH:
3548 Define this if the environment is in flash memory.
3550 a) The environment occupies one whole flash sector, which is
3551 "embedded" in the text segment with the U-Boot code. This
3552 happens usually with "bottom boot sector" or "top boot
3553 sector" type flash chips, which have several smaller
3554 sectors at the start or the end. For instance, such a
3555 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3556 such a case you would place the environment in one of the
3557 4 kB sectors - with U-Boot code before and after it. With
3558 "top boot sector" type flash chips, you would put the
3559 environment in one of the last sectors, leaving a gap
3560 between U-Boot and the environment.
3562 - CONFIG_ENV_OFFSET:
3564 Offset of environment data (variable area) to the
3565 beginning of flash memory; for instance, with bottom boot
3566 type flash chips the second sector can be used: the offset
3567 for this sector is given here.
3569 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3573 This is just another way to specify the start address of
3574 the flash sector containing the environment (instead of
3577 - CONFIG_ENV_SECT_SIZE:
3579 Size of the sector containing the environment.
3582 b) Sometimes flash chips have few, equal sized, BIG sectors.
3583 In such a case you don't want to spend a whole sector for
3588 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3589 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3590 of this flash sector for the environment. This saves
3591 memory for the RAM copy of the environment.
3593 It may also save flash memory if you decide to use this
3594 when your environment is "embedded" within U-Boot code,
3595 since then the remainder of the flash sector could be used
3596 for U-Boot code. It should be pointed out that this is
3597 STRONGLY DISCOURAGED from a robustness point of view:
3598 updating the environment in flash makes it always
3599 necessary to erase the WHOLE sector. If something goes
3600 wrong before the contents has been restored from a copy in
3601 RAM, your target system will be dead.
3603 - CONFIG_ENV_ADDR_REDUND
3604 CONFIG_ENV_SIZE_REDUND
3606 These settings describe a second storage area used to hold
3607 a redundant copy of the environment data, so that there is
3608 a valid backup copy in case there is a power failure during
3609 a "saveenv" operation.
3611 BE CAREFUL! Any changes to the flash layout, and some changes to the
3612 source code will make it necessary to adapt <board>/u-boot.lds*
3616 - CONFIG_ENV_IS_IN_NVRAM:
3618 Define this if you have some non-volatile memory device
3619 (NVRAM, battery buffered SRAM) which you want to use for the
3625 These two #defines are used to determine the memory area you
3626 want to use for environment. It is assumed that this memory
3627 can just be read and written to, without any special
3630 BE CAREFUL! The first access to the environment happens quite early
3631 in U-Boot initalization (when we try to get the setting of for the
3632 console baudrate). You *MUST* have mapped your NVRAM area then, or
3635 Please note that even with NVRAM we still use a copy of the
3636 environment in RAM: we could work on NVRAM directly, but we want to
3637 keep settings there always unmodified except somebody uses "saveenv"
3638 to save the current settings.
3641 - CONFIG_ENV_IS_IN_EEPROM:
3643 Use this if you have an EEPROM or similar serial access
3644 device and a driver for it.
3646 - CONFIG_ENV_OFFSET:
3649 These two #defines specify the offset and size of the
3650 environment area within the total memory of your EEPROM.
3652 - CONFIG_SYS_I2C_EEPROM_ADDR:
3653 If defined, specified the chip address of the EEPROM device.
3654 The default address is zero.
3656 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3657 If defined, the number of bits used to address bytes in a
3658 single page in the EEPROM device. A 64 byte page, for example
3659 would require six bits.
3661 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3662 If defined, the number of milliseconds to delay between
3663 page writes. The default is zero milliseconds.
3665 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3666 The length in bytes of the EEPROM memory array address. Note
3667 that this is NOT the chip address length!
3669 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3670 EEPROM chips that implement "address overflow" are ones
3671 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3672 address and the extra bits end up in the "chip address" bit
3673 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3676 Note that we consider the length of the address field to
3677 still be one byte because the extra address bits are hidden
3678 in the chip address.
3680 - CONFIG_SYS_EEPROM_SIZE:
3681 The size in bytes of the EEPROM device.
3683 - CONFIG_ENV_EEPROM_IS_ON_I2C
3684 define this, if you have I2C and SPI activated, and your
3685 EEPROM, which holds the environment, is on the I2C bus.
3687 - CONFIG_I2C_ENV_EEPROM_BUS
3688 if you have an Environment on an EEPROM reached over
3689 I2C muxes, you can define here, how to reach this
3690 EEPROM. For example:
3692 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3694 EEPROM which holds the environment, is reached over
3695 a pca9547 i2c mux with address 0x70, channel 3.
3697 - CONFIG_ENV_IS_IN_DATAFLASH:
3699 Define this if you have a DataFlash memory device which you
3700 want to use for the environment.
3702 - CONFIG_ENV_OFFSET:
3706 These three #defines specify the offset and size of the
3707 environment area within the total memory of your DataFlash placed
3708 at the specified address.
3710 - CONFIG_ENV_IS_IN_REMOTE:
3712 Define this if you have a remote memory space which you
3713 want to use for the local device's environment.
3718 These two #defines specify the address and size of the
3719 environment area within the remote memory space. The
3720 local device can get the environment from remote memory
3721 space by SRIO or PCIE links.
3723 BE CAREFUL! For some special cases, the local device can not use
3724 "saveenv" command. For example, the local device will get the
3725 environment stored in a remote NOR flash by SRIO or PCIE link,
3726 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3728 - CONFIG_ENV_IS_IN_NAND:
3730 Define this if you have a NAND device which you want to use
3731 for the environment.
3733 - CONFIG_ENV_OFFSET:
3736 These two #defines specify the offset and size of the environment
3737 area within the first NAND device. CONFIG_ENV_OFFSET must be
3738 aligned to an erase block boundary.
3740 - CONFIG_ENV_OFFSET_REDUND (optional):
3742 This setting describes a second storage area of CONFIG_ENV_SIZE
3743 size used to hold a redundant copy of the environment data, so
3744 that there is a valid backup copy in case there is a power failure
3745 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3746 aligned to an erase block boundary.
3748 - CONFIG_ENV_RANGE (optional):
3750 Specifies the length of the region in which the environment
3751 can be written. This should be a multiple of the NAND device's
3752 block size. Specifying a range with more erase blocks than
3753 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3754 the range to be avoided.
3756 - CONFIG_ENV_OFFSET_OOB (optional):
3758 Enables support for dynamically retrieving the offset of the
3759 environment from block zero's out-of-band data. The
3760 "nand env.oob" command can be used to record this offset.
3761 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3762 using CONFIG_ENV_OFFSET_OOB.
3764 - CONFIG_NAND_ENV_DST
3766 Defines address in RAM to which the nand_spl code should copy the
3767 environment. If redundant environment is used, it will be copied to
3768 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3770 - CONFIG_ENV_IS_IN_UBI:
3772 Define this if you have an UBI volume that you want to use for the
3773 environment. This has the benefit of wear-leveling the environment
3774 accesses, which is important on NAND.
3776 - CONFIG_ENV_UBI_PART:
3778 Define this to a string that is the mtd partition containing the UBI.
3780 - CONFIG_ENV_UBI_VOLUME:
3782 Define this to the name of the volume that you want to store the
3785 - CONFIG_ENV_UBI_VOLUME_REDUND:
3787 Define this to the name of another volume to store a second copy of
3788 the environment in. This will enable redundant environments in UBI.
3789 It is assumed that both volumes are in the same MTD partition.
3791 - CONFIG_UBI_SILENCE_MSG
3792 - CONFIG_UBIFS_SILENCE_MSG
3794 You will probably want to define these to avoid a really noisy system
3795 when storing the env in UBI.
3797 - CONFIG_ENV_IS_IN_MMC:
3799 Define this if you have an MMC device which you want to use for the
3802 - CONFIG_SYS_MMC_ENV_DEV:
3804 Specifies which MMC device the environment is stored in.
3806 - CONFIG_SYS_MMC_ENV_PART (optional):
3808 Specifies which MMC partition the environment is stored in. If not
3809 set, defaults to partition 0, the user area. Common values might be
3810 1 (first MMC boot partition), 2 (second MMC boot partition).
3812 - CONFIG_ENV_OFFSET:
3815 These two #defines specify the offset and size of the environment
3816 area within the specified MMC device.
3818 If offset is positive (the usual case), it is treated as relative to
3819 the start of the MMC partition. If offset is negative, it is treated
3820 as relative to the end of the MMC partition. This can be useful if
3821 your board may be fitted with different MMC devices, which have
3822 different sizes for the MMC partitions, and you always want the
3823 environment placed at the very end of the partition, to leave the
3824 maximum possible space before it, to store other data.
3826 These two values are in units of bytes, but must be aligned to an
3827 MMC sector boundary.
3829 - CONFIG_ENV_OFFSET_REDUND (optional):
3831 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3832 hold a redundant copy of the environment data. This provides a
3833 valid backup copy in case the other copy is corrupted, e.g. due
3834 to a power failure during a "saveenv" operation.
3836 This value may also be positive or negative; this is handled in the
3837 same way as CONFIG_ENV_OFFSET.
3839 This value is also in units of bytes, but must also be aligned to
3840 an MMC sector boundary.
3842 - CONFIG_ENV_SIZE_REDUND (optional):
3844 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3845 set. If this value is set, it must be set to the same value as
3848 - CONFIG_SYS_SPI_INIT_OFFSET
3850 Defines offset to the initial SPI buffer area in DPRAM. The
3851 area is used at an early stage (ROM part) if the environment
3852 is configured to reside in the SPI EEPROM: We need a 520 byte
3853 scratch DPRAM area. It is used between the two initialization
3854 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3855 to be a good choice since it makes it far enough from the
3856 start of the data area as well as from the stack pointer.
3858 Please note that the environment is read-only until the monitor
3859 has been relocated to RAM and a RAM copy of the environment has been
3860 created; also, when using EEPROM you will have to use getenv_f()
3861 until then to read environment variables.
3863 The environment is protected by a CRC32 checksum. Before the monitor
3864 is relocated into RAM, as a result of a bad CRC you will be working
3865 with the compiled-in default environment - *silently*!!! [This is
3866 necessary, because the first environment variable we need is the
3867 "baudrate" setting for the console - if we have a bad CRC, we don't
3868 have any device yet where we could complain.]
3870 Note: once the monitor has been relocated, then it will complain if
3871 the default environment is used; a new CRC is computed as soon as you
3872 use the "saveenv" command to store a valid environment.
3874 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3875 Echo the inverted Ethernet link state to the fault LED.
3877 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3878 also needs to be defined.
3880 - CONFIG_SYS_FAULT_MII_ADDR:
3881 MII address of the PHY to check for the Ethernet link state.
3883 - CONFIG_NS16550_MIN_FUNCTIONS:
3884 Define this if you desire to only have use of the NS16550_init
3885 and NS16550_putc functions for the serial driver located at
3886 drivers/serial/ns16550.c. This option is useful for saving
3887 space for already greatly restricted images, including but not
3888 limited to NAND_SPL configurations.
3890 - CONFIG_DISPLAY_BOARDINFO
3891 Display information about the board that U-Boot is running on
3892 when U-Boot starts up. The board function checkboard() is called
3895 - CONFIG_DISPLAY_BOARDINFO_LATE
3896 Similar to the previous option, but display this information
3897 later, once stdio is running and output goes to the LCD, if
3900 Low Level (hardware related) configuration options:
3901 ---------------------------------------------------
3903 - CONFIG_SYS_CACHELINE_SIZE:
3904 Cache Line Size of the CPU.
3906 - CONFIG_SYS_DEFAULT_IMMR:
3907 Default address of the IMMR after system reset.
3909 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3910 and RPXsuper) to be able to adjust the position of
3911 the IMMR register after a reset.
3913 - CONFIG_SYS_CCSRBAR_DEFAULT:
3914 Default (power-on reset) physical address of CCSR on Freescale
3917 - CONFIG_SYS_CCSRBAR:
3918 Virtual address of CCSR. On a 32-bit build, this is typically
3919 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3921 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3922 for cross-platform code that uses that macro instead.
3924 - CONFIG_SYS_CCSRBAR_PHYS:
3925 Physical address of CCSR. CCSR can be relocated to a new
3926 physical address, if desired. In this case, this macro should
3927 be set to that address. Otherwise, it should be set to the
3928 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3929 is typically relocated on 36-bit builds. It is recommended
3930 that this macro be defined via the _HIGH and _LOW macros:
3932 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3933 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3935 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3936 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3937 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3938 used in assembly code, so it must not contain typecasts or
3939 integer size suffixes (e.g. "ULL").
3941 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3942 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3943 used in assembly code, so it must not contain typecasts or
3944 integer size suffixes (e.g. "ULL").
3946 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3947 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3948 forced to a value that ensures that CCSR is not relocated.
3950 - Floppy Disk Support:
3951 CONFIG_SYS_FDC_DRIVE_NUMBER
3953 the default drive number (default value 0)
3955 CONFIG_SYS_ISA_IO_STRIDE
3957 defines the spacing between FDC chipset registers
3960 CONFIG_SYS_ISA_IO_OFFSET
3962 defines the offset of register from address. It
3963 depends on which part of the data bus is connected to
3964 the FDC chipset. (default value 0)
3966 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3967 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3970 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3971 fdc_hw_init() is called at the beginning of the FDC
3972 setup. fdc_hw_init() must be provided by the board
3973 source code. It is used to make hardware dependant
3977 Most IDE controllers were designed to be connected with PCI
3978 interface. Only few of them were designed for AHB interface.
3979 When software is doing ATA command and data transfer to
3980 IDE devices through IDE-AHB controller, some additional
3981 registers accessing to these kind of IDE-AHB controller
3984 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3985 DO NOT CHANGE unless you know exactly what you're
3986 doing! (11-4) [MPC8xx/82xx systems only]
3988 - CONFIG_SYS_INIT_RAM_ADDR:
3990 Start address of memory area that can be used for
3991 initial data and stack; please note that this must be
3992 writable memory that is working WITHOUT special
3993 initialization, i. e. you CANNOT use normal RAM which
3994 will become available only after programming the
3995 memory controller and running certain initialization
3998 U-Boot uses the following memory types:
3999 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
4000 - MPC824X: data cache
4001 - PPC4xx: data cache
4003 - CONFIG_SYS_GBL_DATA_OFFSET:
4005 Offset of the initial data structure in the memory
4006 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4007 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4008 data is located at the end of the available space
4009 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4010 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4011 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4012 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4015 On the MPC824X (or other systems that use the data
4016 cache for initial memory) the address chosen for
4017 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4018 point to an otherwise UNUSED address space between
4019 the top of RAM and the start of the PCI space.
4021 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4023 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4025 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4027 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4029 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4031 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4033 - CONFIG_SYS_OR_TIMING_SDRAM:
4036 - CONFIG_SYS_MAMR_PTA:
4037 periodic timer for refresh
4039 - CONFIG_SYS_DER: Debug Event Register (37-47)
4041 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4042 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4043 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4044 CONFIG_SYS_BR1_PRELIM:
4045 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4047 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4048 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4049 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4050 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4052 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4053 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4054 Machine Mode Register and Memory Periodic Timer
4055 Prescaler definitions (SDRAM timing)
4057 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4058 enable I2C microcode relocation patch (MPC8xx);
4059 define relocation offset in DPRAM [DSP2]
4061 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4062 enable SMC microcode relocation patch (MPC8xx);
4063 define relocation offset in DPRAM [SMC1]
4065 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4066 enable SPI microcode relocation patch (MPC8xx);
4067 define relocation offset in DPRAM [SCC4]
4069 - CONFIG_SYS_USE_OSCCLK:
4070 Use OSCM clock mode on MBX8xx board. Be careful,
4071 wrong setting might damage your board. Read
4072 doc/README.MBX before setting this variable!
4074 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4075 Offset of the bootmode word in DPRAM used by post
4076 (Power On Self Tests). This definition overrides
4077 #define'd default value in commproc.h resp.
4080 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4081 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4082 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4083 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4084 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4085 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4086 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4087 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4088 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4090 - CONFIG_PCI_DISABLE_PCIE:
4091 Disable PCI-Express on systems where it is supported but not
4094 - CONFIG_PCI_ENUM_ONLY
4095 Only scan through and get the devices on the busses.
4096 Don't do any setup work, presumably because someone or
4097 something has already done it, and we don't need to do it
4098 a second time. Useful for platforms that are pre-booted
4099 by coreboot or similar.
4101 - CONFIG_PCI_INDIRECT_BRIDGE:
4102 Enable support for indirect PCI bridges.
4105 Chip has SRIO or not
4108 Board has SRIO 1 port available
4111 Board has SRIO 2 port available
4113 - CONFIG_SRIO_PCIE_BOOT_MASTER
4114 Board can support master function for Boot from SRIO and PCIE
4116 - CONFIG_SYS_SRIOn_MEM_VIRT:
4117 Virtual Address of SRIO port 'n' memory region
4119 - CONFIG_SYS_SRIOn_MEM_PHYS:
4120 Physical Address of SRIO port 'n' memory region
4122 - CONFIG_SYS_SRIOn_MEM_SIZE:
4123 Size of SRIO port 'n' memory region
4125 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4126 Defined to tell the NAND controller that the NAND chip is using
4128 Not all NAND drivers use this symbol.
4129 Example of drivers that use it:
4130 - drivers/mtd/nand/ndfc.c
4131 - drivers/mtd/nand/mxc_nand.c
4133 - CONFIG_SYS_NDFC_EBC0_CFG
4134 Sets the EBC0_CFG register for the NDFC. If not defined
4135 a default value will be used.
4138 Get DDR timing information from an I2C EEPROM. Common
4139 with pluggable memory modules such as SODIMMs
4142 I2C address of the SPD EEPROM
4144 - CONFIG_SYS_SPD_BUS_NUM
4145 If SPD EEPROM is on an I2C bus other than the first
4146 one, specify here. Note that the value must resolve
4147 to something your driver can deal with.
4149 - CONFIG_SYS_DDR_RAW_TIMING
4150 Get DDR timing information from other than SPD. Common with
4151 soldered DDR chips onboard without SPD. DDR raw timing
4152 parameters are extracted from datasheet and hard-coded into
4153 header files or board specific files.
4155 - CONFIG_FSL_DDR_INTERACTIVE
4156 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4158 - CONFIG_SYS_83XX_DDR_USES_CS0
4159 Only for 83xx systems. If specified, then DDR should
4160 be configured using CS0 and CS1 instead of CS2 and CS3.
4162 - CONFIG_ETHER_ON_FEC[12]
4163 Define to enable FEC[12] on a 8xx series processor.
4165 - CONFIG_FEC[12]_PHY
4166 Define to the hardcoded PHY address which corresponds
4167 to the given FEC; i. e.
4168 #define CONFIG_FEC1_PHY 4
4169 means that the PHY with address 4 is connected to FEC1
4171 When set to -1, means to probe for first available.
4173 - CONFIG_FEC[12]_PHY_NORXERR
4174 The PHY does not have a RXERR line (RMII only).
4175 (so program the FEC to ignore it).
4178 Enable RMII mode for all FECs.
4179 Note that this is a global option, we can't
4180 have one FEC in standard MII mode and another in RMII mode.
4182 - CONFIG_CRC32_VERIFY
4183 Add a verify option to the crc32 command.
4186 => crc32 -v <address> <count> <crc32>
4188 Where address/count indicate a memory area
4189 and crc32 is the correct crc32 which the
4193 Add the "loopw" memory command. This only takes effect if
4194 the memory commands are activated globally (CONFIG_CMD_MEM).
4197 Add the "mdc" and "mwc" memory commands. These are cyclic
4202 This command will print 4 bytes (10,11,12,13) each 500 ms.
4204 => mwc.l 100 12345678 10
4205 This command will write 12345678 to address 100 all 10 ms.
4207 This only takes effect if the memory commands are activated
4208 globally (CONFIG_CMD_MEM).
4210 - CONFIG_SKIP_LOWLEVEL_INIT
4211 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4212 low level initializations (like setting up the memory
4213 controller) are omitted and/or U-Boot does not
4214 relocate itself into RAM.
4216 Normally this variable MUST NOT be defined. The only
4217 exception is when U-Boot is loaded (to RAM) by some
4218 other boot loader or by a debugger which performs
4219 these initializations itself.
4222 Modifies the behaviour of start.S when compiling a loader
4223 that is executed before the actual U-Boot. E.g. when
4224 compiling a NAND SPL.
4227 Modifies the behaviour of start.S when compiling a loader
4228 that is executed after the SPL and before the actual U-Boot.
4229 It is loaded by the SPL.
4231 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4232 Only for 85xx systems. If this variable is specified, the section
4233 .resetvec is not kept and the section .bootpg is placed in the
4234 previous 4k of the .text section.
4236 - CONFIG_ARCH_MAP_SYSMEM
4237 Generally U-Boot (and in particular the md command) uses
4238 effective address. It is therefore not necessary to regard
4239 U-Boot address as virtual addresses that need to be translated
4240 to physical addresses. However, sandbox requires this, since
4241 it maintains its own little RAM buffer which contains all
4242 addressable memory. This option causes some memory accesses
4243 to be mapped through map_sysmem() / unmap_sysmem().
4245 - CONFIG_USE_ARCH_MEMCPY
4246 CONFIG_USE_ARCH_MEMSET
4247 If these options are used a optimized version of memcpy/memset will
4248 be used if available. These functions may be faster under some
4249 conditions but may increase the binary size.
4251 - CONFIG_X86_RESET_VECTOR
4252 If defined, the x86 reset vector code is included. This is not
4253 needed when U-Boot is running from Coreboot.
4256 Defines the MPU clock speed (in MHz).
4258 NOTE : currently only supported on AM335x platforms.
4260 Freescale QE/FMAN Firmware Support:
4261 -----------------------------------
4263 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4264 loading of "firmware", which is encoded in the QE firmware binary format.
4265 This firmware often needs to be loaded during U-Boot booting, so macros
4266 are used to identify the storage device (NOR flash, SPI, etc) and the address
4269 - CONFIG_SYS_QE_FMAN_FW_ADDR
4270 The address in the storage device where the firmware is located. The
4271 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4274 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4275 The maximum possible size of the firmware. The firmware binary format
4276 has a field that specifies the actual size of the firmware, but it
4277 might not be possible to read any part of the firmware unless some
4278 local storage is allocated to hold the entire firmware first.
4280 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4281 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4282 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4283 virtual address in NOR flash.
4285 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4286 Specifies that QE/FMAN firmware is located in NAND flash.
4287 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4289 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4290 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4291 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4293 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4294 Specifies that QE/FMAN firmware is located on the primary SPI
4295 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4297 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4298 Specifies that QE/FMAN firmware is located in the remote (master)
4299 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4300 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4301 window->master inbound window->master LAW->the ucode address in
4302 master's memory space.
4304 Building the Software:
4305 ======================
4307 Building U-Boot has been tested in several native build environments
4308 and in many different cross environments. Of course we cannot support
4309 all possibly existing versions of cross development tools in all
4310 (potentially obsolete) versions. In case of tool chain problems we
4311 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4312 which is extensively used to build and test U-Boot.
4314 If you are not using a native environment, it is assumed that you
4315 have GNU cross compiling tools available in your path. In this case,
4316 you must set the environment variable CROSS_COMPILE in your shell.
4317 Note that no changes to the Makefile or any other source files are
4318 necessary. For example using the ELDK on a 4xx CPU, please enter:
4320 $ CROSS_COMPILE=ppc_4xx-
4321 $ export CROSS_COMPILE
4323 Note: If you wish to generate Windows versions of the utilities in
4324 the tools directory you can use the MinGW toolchain
4325 (http://www.mingw.org). Set your HOST tools to the MinGW
4326 toolchain and execute 'make tools'. For example:
4328 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4330 Binaries such as tools/mkimage.exe will be created which can
4331 be executed on computers running Windows.
4333 U-Boot is intended to be simple to build. After installing the
4334 sources you must configure U-Boot for one specific board type. This
4339 where "NAME_config" is the name of one of the existing configu-
4340 rations; see boards.cfg for supported names.
4342 Note: for some board special configuration names may exist; check if
4343 additional information is available from the board vendor; for
4344 instance, the TQM823L systems are available without (standard)
4345 or with LCD support. You can select such additional "features"
4346 when choosing the configuration, i. e.
4349 - will configure for a plain TQM823L, i. e. no LCD support
4351 make TQM823L_LCD_config
4352 - will configure for a TQM823L with U-Boot console on LCD
4357 Finally, type "make all", and you should get some working U-Boot
4358 images ready for download to / installation on your system:
4360 - "u-boot.bin" is a raw binary image
4361 - "u-boot" is an image in ELF binary format
4362 - "u-boot.srec" is in Motorola S-Record format
4364 By default the build is performed locally and the objects are saved
4365 in the source directory. One of the two methods can be used to change
4366 this behavior and build U-Boot to some external directory:
4368 1. Add O= to the make command line invocations:
4370 make O=/tmp/build distclean
4371 make O=/tmp/build NAME_config
4372 make O=/tmp/build all
4374 2. Set environment variable BUILD_DIR to point to the desired location:
4376 export BUILD_DIR=/tmp/build
4381 Note that the command line "O=" setting overrides the BUILD_DIR environment
4385 Please be aware that the Makefiles assume you are using GNU make, so
4386 for instance on NetBSD you might need to use "gmake" instead of
4390 If the system board that you have is not listed, then you will need
4391 to port U-Boot to your hardware platform. To do this, follow these
4394 1. Add a new configuration option for your board to the toplevel
4395 "boards.cfg" file, using the existing entries as examples.
4396 Follow the instructions there to keep the boards in order.
4397 2. Create a new directory to hold your board specific code. Add any
4398 files you need. In your board directory, you will need at least
4399 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4400 3. Create a new configuration file "include/configs/<board>.h" for
4402 3. If you're porting U-Boot to a new CPU, then also create a new
4403 directory to hold your CPU specific code. Add any files you need.
4404 4. Run "make <board>_config" with your new name.
4405 5. Type "make", and you should get a working "u-boot.srec" file
4406 to be installed on your target system.
4407 6. Debug and solve any problems that might arise.
4408 [Of course, this last step is much harder than it sounds.]
4411 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4412 ==============================================================
4414 If you have modified U-Boot sources (for instance added a new board
4415 or support for new devices, a new CPU, etc.) you are expected to
4416 provide feedback to the other developers. The feedback normally takes
4417 the form of a "patch", i. e. a context diff against a certain (latest
4418 official or latest in the git repository) version of U-Boot sources.
4420 But before you submit such a patch, please verify that your modifi-
4421 cation did not break existing code. At least make sure that *ALL* of
4422 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4423 just run the "MAKEALL" script, which will configure and build U-Boot
4424 for ALL supported system. Be warned, this will take a while. You can
4425 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4426 environment variable to the script, i. e. to use the ELDK cross tools
4429 CROSS_COMPILE=ppc_8xx- MAKEALL
4431 or to build on a native PowerPC system you can type
4433 CROSS_COMPILE=' ' MAKEALL
4435 When using the MAKEALL script, the default behaviour is to build
4436 U-Boot in the source directory. This location can be changed by
4437 setting the BUILD_DIR environment variable. Also, for each target
4438 built, the MAKEALL script saves two log files (<target>.ERR and
4439 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4440 location can be changed by setting the MAKEALL_LOGDIR environment
4441 variable. For example:
4443 export BUILD_DIR=/tmp/build
4444 export MAKEALL_LOGDIR=/tmp/log
4445 CROSS_COMPILE=ppc_8xx- MAKEALL
4447 With the above settings build objects are saved in the /tmp/build,
4448 log files are saved in the /tmp/log and the source tree remains clean
4449 during the whole build process.
4452 See also "U-Boot Porting Guide" below.
4455 Monitor Commands - Overview:
4456 ============================
4458 go - start application at address 'addr'
4459 run - run commands in an environment variable
4460 bootm - boot application image from memory
4461 bootp - boot image via network using BootP/TFTP protocol
4462 bootz - boot zImage from memory
4463 tftpboot- boot image via network using TFTP protocol
4464 and env variables "ipaddr" and "serverip"
4465 (and eventually "gatewayip")
4466 tftpput - upload a file via network using TFTP protocol
4467 rarpboot- boot image via network using RARP/TFTP protocol
4468 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4469 loads - load S-Record file over serial line
4470 loadb - load binary file over serial line (kermit mode)
4472 mm - memory modify (auto-incrementing)
4473 nm - memory modify (constant address)
4474 mw - memory write (fill)
4476 cmp - memory compare
4477 crc32 - checksum calculation
4478 i2c - I2C sub-system
4479 sspi - SPI utility commands
4480 base - print or set address offset
4481 printenv- print environment variables
4482 setenv - set environment variables
4483 saveenv - save environment variables to persistent storage
4484 protect - enable or disable FLASH write protection
4485 erase - erase FLASH memory
4486 flinfo - print FLASH memory information
4487 nand - NAND memory operations (see doc/README.nand)
4488 bdinfo - print Board Info structure
4489 iminfo - print header information for application image
4490 coninfo - print console devices and informations
4491 ide - IDE sub-system
4492 loop - infinite loop on address range
4493 loopw - infinite write loop on address range
4494 mtest - simple RAM test
4495 icache - enable or disable instruction cache
4496 dcache - enable or disable data cache
4497 reset - Perform RESET of the CPU
4498 echo - echo args to console
4499 version - print monitor version
4500 help - print online help
4501 ? - alias for 'help'
4504 Monitor Commands - Detailed Description:
4505 ========================================
4509 For now: just type "help <command>".
4512 Environment Variables:
4513 ======================
4515 U-Boot supports user configuration using Environment Variables which
4516 can be made persistent by saving to Flash memory.
4518 Environment Variables are set using "setenv", printed using
4519 "printenv", and saved to Flash using "saveenv". Using "setenv"
4520 without a value can be used to delete a variable from the
4521 environment. As long as you don't save the environment you are
4522 working with an in-memory copy. In case the Flash area containing the
4523 environment is erased by accident, a default environment is provided.
4525 Some configuration options can be set using Environment Variables.
4527 List of environment variables (most likely not complete):
4529 baudrate - see CONFIG_BAUDRATE
4531 bootdelay - see CONFIG_BOOTDELAY
4533 bootcmd - see CONFIG_BOOTCOMMAND
4535 bootargs - Boot arguments when booting an RTOS image
4537 bootfile - Name of the image to load with TFTP
4539 bootm_low - Memory range available for image processing in the bootm
4540 command can be restricted. This variable is given as
4541 a hexadecimal number and defines lowest address allowed
4542 for use by the bootm command. See also "bootm_size"
4543 environment variable. Address defined by "bootm_low" is
4544 also the base of the initial memory mapping for the Linux
4545 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4548 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4549 This variable is given as a hexadecimal number and it
4550 defines the size of the memory region starting at base
4551 address bootm_low that is accessible by the Linux kernel
4552 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4553 as the default value if it is defined, and bootm_size is
4556 bootm_size - Memory range available for image processing in the bootm
4557 command can be restricted. This variable is given as
4558 a hexadecimal number and defines the size of the region
4559 allowed for use by the bootm command. See also "bootm_low"
4560 environment variable.
4562 updatefile - Location of the software update file on a TFTP server, used
4563 by the automatic software update feature. Please refer to
4564 documentation in doc/README.update for more details.
4566 autoload - if set to "no" (any string beginning with 'n'),
4567 "bootp" will just load perform a lookup of the
4568 configuration from the BOOTP server, but not try to
4569 load any image using TFTP
4571 autostart - if set to "yes", an image loaded using the "bootp",
4572 "rarpboot", "tftpboot" or "diskboot" commands will
4573 be automatically started (by internally calling
4576 If set to "no", a standalone image passed to the
4577 "bootm" command will be copied to the load address
4578 (and eventually uncompressed), but NOT be started.
4579 This can be used to load and uncompress arbitrary
4582 fdt_high - if set this restricts the maximum address that the
4583 flattened device tree will be copied into upon boot.
4584 For example, if you have a system with 1 GB memory
4585 at physical address 0x10000000, while Linux kernel
4586 only recognizes the first 704 MB as low memory, you
4587 may need to set fdt_high as 0x3C000000 to have the
4588 device tree blob be copied to the maximum address
4589 of the 704 MB low memory, so that Linux kernel can
4590 access it during the boot procedure.
4592 If this is set to the special value 0xFFFFFFFF then
4593 the fdt will not be copied at all on boot. For this
4594 to work it must reside in writable memory, have
4595 sufficient padding on the end of it for u-boot to
4596 add the information it needs into it, and the memory
4597 must be accessible by the kernel.
4599 fdtcontroladdr- if set this is the address of the control flattened
4600 device tree used by U-Boot when CONFIG_OF_CONTROL is
4603 i2cfast - (PPC405GP|PPC405EP only)
4604 if set to 'y' configures Linux I2C driver for fast
4605 mode (400kHZ). This environment variable is used in
4606 initialization code. So, for changes to be effective
4607 it must be saved and board must be reset.
4609 initrd_high - restrict positioning of initrd images:
4610 If this variable is not set, initrd images will be
4611 copied to the highest possible address in RAM; this
4612 is usually what you want since it allows for
4613 maximum initrd size. If for some reason you want to
4614 make sure that the initrd image is loaded below the
4615 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4616 variable to a value of "no" or "off" or "0".
4617 Alternatively, you can set it to a maximum upper
4618 address to use (U-Boot will still check that it
4619 does not overwrite the U-Boot stack and data).
4621 For instance, when you have a system with 16 MB
4622 RAM, and want to reserve 4 MB from use by Linux,
4623 you can do this by adding "mem=12M" to the value of
4624 the "bootargs" variable. However, now you must make
4625 sure that the initrd image is placed in the first
4626 12 MB as well - this can be done with
4628 setenv initrd_high 00c00000
4630 If you set initrd_high to 0xFFFFFFFF, this is an
4631 indication to U-Boot that all addresses are legal
4632 for the Linux kernel, including addresses in flash
4633 memory. In this case U-Boot will NOT COPY the
4634 ramdisk at all. This may be useful to reduce the
4635 boot time on your system, but requires that this
4636 feature is supported by your Linux kernel.
4638 ipaddr - IP address; needed for tftpboot command
4640 loadaddr - Default load address for commands like "bootp",
4641 "rarpboot", "tftpboot", "loadb" or "diskboot"
4643 loads_echo - see CONFIG_LOADS_ECHO
4645 serverip - TFTP server IP address; needed for tftpboot command
4647 bootretry - see CONFIG_BOOT_RETRY_TIME
4649 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4651 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4653 ethprime - controls which interface is used first.
4655 ethact - controls which interface is currently active.
4656 For example you can do the following
4658 => setenv ethact FEC
4659 => ping 192.168.0.1 # traffic sent on FEC
4660 => setenv ethact SCC
4661 => ping 10.0.0.1 # traffic sent on SCC
4663 ethrotate - When set to "no" U-Boot does not go through all
4664 available network interfaces.
4665 It just stays at the currently selected interface.
4667 netretry - When set to "no" each network operation will
4668 either succeed or fail without retrying.
4669 When set to "once" the network operation will
4670 fail when all the available network interfaces
4671 are tried once without success.
4672 Useful on scripts which control the retry operation
4675 npe_ucode - set load address for the NPE microcode
4677 silent_linux - If set then linux will be told to boot silently, by
4678 changing the console to be empty. If "yes" it will be
4679 made silent. If "no" it will not be made silent. If
4680 unset, then it will be made silent if the U-Boot console
4683 tftpsrcport - If this is set, the value is used for TFTP's
4686 tftpdstport - If this is set, the value is used for TFTP's UDP
4687 destination port instead of the Well Know Port 69.
4689 tftpblocksize - Block size to use for TFTP transfers; if not set,
4690 we use the TFTP server's default block size
4692 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4693 seconds, minimum value is 1000 = 1 second). Defines
4694 when a packet is considered to be lost so it has to
4695 be retransmitted. The default is 5000 = 5 seconds.
4696 Lowering this value may make downloads succeed
4697 faster in networks with high packet loss rates or
4698 with unreliable TFTP servers.
4700 vlan - When set to a value < 4095 the traffic over
4701 Ethernet is encapsulated/received over 802.1q
4704 The following image location variables contain the location of images
4705 used in booting. The "Image" column gives the role of the image and is
4706 not an environment variable name. The other columns are environment
4707 variable names. "File Name" gives the name of the file on a TFTP
4708 server, "RAM Address" gives the location in RAM the image will be
4709 loaded to, and "Flash Location" gives the image's address in NOR
4710 flash or offset in NAND flash.
4712 *Note* - these variables don't have to be defined for all boards, some
4713 boards currenlty use other variables for these purposes, and some
4714 boards use these variables for other purposes.
4716 Image File Name RAM Address Flash Location
4717 ----- --------- ----------- --------------
4718 u-boot u-boot u-boot_addr_r u-boot_addr
4719 Linux kernel bootfile kernel_addr_r kernel_addr
4720 device tree blob fdtfile fdt_addr_r fdt_addr
4721 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4723 The following environment variables may be used and automatically
4724 updated by the network boot commands ("bootp" and "rarpboot"),
4725 depending the information provided by your boot server:
4727 bootfile - see above
4728 dnsip - IP address of your Domain Name Server
4729 dnsip2 - IP address of your secondary Domain Name Server
4730 gatewayip - IP address of the Gateway (Router) to use
4731 hostname - Target hostname
4733 netmask - Subnet Mask
4734 rootpath - Pathname of the root filesystem on the NFS server
4735 serverip - see above
4738 There are two special Environment Variables:
4740 serial# - contains hardware identification information such
4741 as type string and/or serial number
4742 ethaddr - Ethernet address
4744 These variables can be set only once (usually during manufacturing of
4745 the board). U-Boot refuses to delete or overwrite these variables
4746 once they have been set once.
4749 Further special Environment Variables:
4751 ver - Contains the U-Boot version string as printed
4752 with the "version" command. This variable is
4753 readonly (see CONFIG_VERSION_VARIABLE).
4756 Please note that changes to some configuration parameters may take
4757 only effect after the next boot (yes, that's just like Windoze :-).
4760 Callback functions for environment variables:
4761 ---------------------------------------------
4763 For some environment variables, the behavior of u-boot needs to change
4764 when their values are changed. This functionailty allows functions to
4765 be associated with arbitrary variables. On creation, overwrite, or
4766 deletion, the callback will provide the opportunity for some side
4767 effect to happen or for the change to be rejected.
4769 The callbacks are named and associated with a function using the
4770 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4772 These callbacks are associated with variables in one of two ways. The
4773 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4774 in the board configuration to a string that defines a list of
4775 associations. The list must be in the following format:
4777 entry = variable_name[:callback_name]
4780 If the callback name is not specified, then the callback is deleted.
4781 Spaces are also allowed anywhere in the list.
4783 Callbacks can also be associated by defining the ".callbacks" variable
4784 with the same list format above. Any association in ".callbacks" will
4785 override any association in the static list. You can define
4786 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4787 ".callbacks" envirnoment variable in the default or embedded environment.
4790 Command Line Parsing:
4791 =====================
4793 There are two different command line parsers available with U-Boot:
4794 the old "simple" one, and the much more powerful "hush" shell:
4796 Old, simple command line parser:
4797 --------------------------------
4799 - supports environment variables (through setenv / saveenv commands)
4800 - several commands on one line, separated by ';'
4801 - variable substitution using "... ${name} ..." syntax
4802 - special characters ('$', ';') can be escaped by prefixing with '\',
4804 setenv bootcmd bootm \${address}
4805 - You can also escape text by enclosing in single apostrophes, for example:
4806 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4811 - similar to Bourne shell, with control structures like
4812 if...then...else...fi, for...do...done; while...do...done,
4813 until...do...done, ...
4814 - supports environment ("global") variables (through setenv / saveenv
4815 commands) and local shell variables (through standard shell syntax
4816 "name=value"); only environment variables can be used with "run"
4822 (1) If a command line (or an environment variable executed by a "run"
4823 command) contains several commands separated by semicolon, and
4824 one of these commands fails, then the remaining commands will be
4827 (2) If you execute several variables with one call to run (i. e.
4828 calling run with a list of variables as arguments), any failing
4829 command will cause "run" to terminate, i. e. the remaining
4830 variables are not executed.
4832 Note for Redundant Ethernet Interfaces:
4833 =======================================
4835 Some boards come with redundant Ethernet interfaces; U-Boot supports
4836 such configurations and is capable of automatic selection of a
4837 "working" interface when needed. MAC assignment works as follows:
4839 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4840 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4841 "eth1addr" (=>eth1), "eth2addr", ...
4843 If the network interface stores some valid MAC address (for instance
4844 in SROM), this is used as default address if there is NO correspon-
4845 ding setting in the environment; if the corresponding environment
4846 variable is set, this overrides the settings in the card; that means:
4848 o If the SROM has a valid MAC address, and there is no address in the
4849 environment, the SROM's address is used.
4851 o If there is no valid address in the SROM, and a definition in the
4852 environment exists, then the value from the environment variable is
4855 o If both the SROM and the environment contain a MAC address, and
4856 both addresses are the same, this MAC address is used.
4858 o If both the SROM and the environment contain a MAC address, and the
4859 addresses differ, the value from the environment is used and a
4862 o If neither SROM nor the environment contain a MAC address, an error
4865 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4866 will be programmed into hardware as part of the initialization process. This
4867 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4868 The naming convention is as follows:
4869 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4874 U-Boot is capable of booting (and performing other auxiliary operations on)
4875 images in two formats:
4877 New uImage format (FIT)
4878 -----------------------
4880 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4881 to Flattened Device Tree). It allows the use of images with multiple
4882 components (several kernels, ramdisks, etc.), with contents protected by
4883 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4889 Old image format is based on binary files which can be basically anything,
4890 preceded by a special header; see the definitions in include/image.h for
4891 details; basically, the header defines the following image properties:
4893 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4894 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4895 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4896 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4898 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4899 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4900 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4901 * Compression Type (uncompressed, gzip, bzip2)
4907 The header is marked by a special Magic Number, and both the header
4908 and the data portions of the image are secured against corruption by
4915 Although U-Boot should support any OS or standalone application
4916 easily, the main focus has always been on Linux during the design of
4919 U-Boot includes many features that so far have been part of some
4920 special "boot loader" code within the Linux kernel. Also, any
4921 "initrd" images to be used are no longer part of one big Linux image;
4922 instead, kernel and "initrd" are separate images. This implementation
4923 serves several purposes:
4925 - the same features can be used for other OS or standalone
4926 applications (for instance: using compressed images to reduce the
4927 Flash memory footprint)
4929 - it becomes much easier to port new Linux kernel versions because
4930 lots of low-level, hardware dependent stuff are done by U-Boot
4932 - the same Linux kernel image can now be used with different "initrd"
4933 images; of course this also means that different kernel images can
4934 be run with the same "initrd". This makes testing easier (you don't
4935 have to build a new "zImage.initrd" Linux image when you just
4936 change a file in your "initrd"). Also, a field-upgrade of the
4937 software is easier now.
4943 Porting Linux to U-Boot based systems:
4944 ---------------------------------------
4946 U-Boot cannot save you from doing all the necessary modifications to
4947 configure the Linux device drivers for use with your target hardware
4948 (no, we don't intend to provide a full virtual machine interface to
4951 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4953 Just make sure your machine specific header file (for instance
4954 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4955 Information structure as we define in include/asm-<arch>/u-boot.h,
4956 and make sure that your definition of IMAP_ADDR uses the same value
4957 as your U-Boot configuration in CONFIG_SYS_IMMR.
4960 Configuring the Linux kernel:
4961 -----------------------------
4963 No specific requirements for U-Boot. Make sure you have some root
4964 device (initial ramdisk, NFS) for your target system.
4967 Building a Linux Image:
4968 -----------------------
4970 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4971 not used. If you use recent kernel source, a new build target
4972 "uImage" will exist which automatically builds an image usable by
4973 U-Boot. Most older kernels also have support for a "pImage" target,
4974 which was introduced for our predecessor project PPCBoot and uses a
4975 100% compatible format.
4984 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4985 encapsulate a compressed Linux kernel image with header information,
4986 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4988 * build a standard "vmlinux" kernel image (in ELF binary format):
4990 * convert the kernel into a raw binary image:
4992 ${CROSS_COMPILE}-objcopy -O binary \
4993 -R .note -R .comment \
4994 -S vmlinux linux.bin
4996 * compress the binary image:
5000 * package compressed binary image for U-Boot:
5002 mkimage -A ppc -O linux -T kernel -C gzip \
5003 -a 0 -e 0 -n "Linux Kernel Image" \
5004 -d linux.bin.gz uImage
5007 The "mkimage" tool can also be used to create ramdisk images for use
5008 with U-Boot, either separated from the Linux kernel image, or
5009 combined into one file. "mkimage" encapsulates the images with a 64
5010 byte header containing information about target architecture,
5011 operating system, image type, compression method, entry points, time
5012 stamp, CRC32 checksums, etc.
5014 "mkimage" can be called in two ways: to verify existing images and
5015 print the header information, or to build new images.
5017 In the first form (with "-l" option) mkimage lists the information
5018 contained in the header of an existing U-Boot image; this includes
5019 checksum verification:
5021 tools/mkimage -l image
5022 -l ==> list image header information
5024 The second form (with "-d" option) is used to build a U-Boot image
5025 from a "data file" which is used as image payload:
5027 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5028 -n name -d data_file image
5029 -A ==> set architecture to 'arch'
5030 -O ==> set operating system to 'os'
5031 -T ==> set image type to 'type'
5032 -C ==> set compression type 'comp'
5033 -a ==> set load address to 'addr' (hex)
5034 -e ==> set entry point to 'ep' (hex)
5035 -n ==> set image name to 'name'
5036 -d ==> use image data from 'datafile'
5038 Right now, all Linux kernels for PowerPC systems use the same load
5039 address (0x00000000), but the entry point address depends on the
5042 - 2.2.x kernels have the entry point at 0x0000000C,
5043 - 2.3.x and later kernels have the entry point at 0x00000000.
5045 So a typical call to build a U-Boot image would read:
5047 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5048 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5049 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5050 > examples/uImage.TQM850L
5051 Image Name: 2.4.4 kernel for TQM850L
5052 Created: Wed Jul 19 02:34:59 2000
5053 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5054 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5055 Load Address: 0x00000000
5056 Entry Point: 0x00000000
5058 To verify the contents of the image (or check for corruption):
5060 -> tools/mkimage -l examples/uImage.TQM850L
5061 Image Name: 2.4.4 kernel for TQM850L
5062 Created: Wed Jul 19 02:34:59 2000
5063 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5064 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5065 Load Address: 0x00000000
5066 Entry Point: 0x00000000
5068 NOTE: for embedded systems where boot time is critical you can trade
5069 speed for memory and install an UNCOMPRESSED image instead: this
5070 needs more space in Flash, but boots much faster since it does not
5071 need to be uncompressed:
5073 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5074 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5075 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5076 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5077 > examples/uImage.TQM850L-uncompressed
5078 Image Name: 2.4.4 kernel for TQM850L
5079 Created: Wed Jul 19 02:34:59 2000
5080 Image Type: PowerPC Linux Kernel Image (uncompressed)
5081 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5082 Load Address: 0x00000000
5083 Entry Point: 0x00000000
5086 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5087 when your kernel is intended to use an initial ramdisk:
5089 -> tools/mkimage -n 'Simple Ramdisk Image' \
5090 > -A ppc -O linux -T ramdisk -C gzip \
5091 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5092 Image Name: Simple Ramdisk Image
5093 Created: Wed Jan 12 14:01:50 2000
5094 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5095 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5096 Load Address: 0x00000000
5097 Entry Point: 0x00000000
5100 Installing a Linux Image:
5101 -------------------------
5103 To downloading a U-Boot image over the serial (console) interface,
5104 you must convert the image to S-Record format:
5106 objcopy -I binary -O srec examples/image examples/image.srec
5108 The 'objcopy' does not understand the information in the U-Boot
5109 image header, so the resulting S-Record file will be relative to
5110 address 0x00000000. To load it to a given address, you need to
5111 specify the target address as 'offset' parameter with the 'loads'
5114 Example: install the image to address 0x40100000 (which on the
5115 TQM8xxL is in the first Flash bank):
5117 => erase 40100000 401FFFFF
5123 ## Ready for S-Record download ...
5124 ~>examples/image.srec
5125 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5127 15989 15990 15991 15992
5128 [file transfer complete]
5130 ## Start Addr = 0x00000000
5133 You can check the success of the download using the 'iminfo' command;
5134 this includes a checksum verification so you can be sure no data
5135 corruption happened:
5139 ## Checking Image at 40100000 ...
5140 Image Name: 2.2.13 for initrd on TQM850L
5141 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5142 Data Size: 335725 Bytes = 327 kB = 0 MB
5143 Load Address: 00000000
5144 Entry Point: 0000000c
5145 Verifying Checksum ... OK
5151 The "bootm" command is used to boot an application that is stored in
5152 memory (RAM or Flash). In case of a Linux kernel image, the contents
5153 of the "bootargs" environment variable is passed to the kernel as
5154 parameters. You can check and modify this variable using the
5155 "printenv" and "setenv" commands:
5158 => printenv bootargs
5159 bootargs=root=/dev/ram
5161 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5163 => printenv bootargs
5164 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5167 ## Booting Linux kernel at 40020000 ...
5168 Image Name: 2.2.13 for NFS on TQM850L
5169 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5170 Data Size: 381681 Bytes = 372 kB = 0 MB
5171 Load Address: 00000000
5172 Entry Point: 0000000c
5173 Verifying Checksum ... OK
5174 Uncompressing Kernel Image ... OK
5175 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
5176 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5177 time_init: decrementer frequency = 187500000/60
5178 Calibrating delay loop... 49.77 BogoMIPS
5179 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5182 If you want to boot a Linux kernel with initial RAM disk, you pass
5183 the memory addresses of both the kernel and the initrd image (PPBCOOT
5184 format!) to the "bootm" command:
5186 => imi 40100000 40200000
5188 ## Checking Image at 40100000 ...
5189 Image Name: 2.2.13 for initrd on TQM850L
5190 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5191 Data Size: 335725 Bytes = 327 kB = 0 MB
5192 Load Address: 00000000
5193 Entry Point: 0000000c
5194 Verifying Checksum ... OK
5196 ## Checking Image at 40200000 ...
5197 Image Name: Simple Ramdisk Image
5198 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5199 Data Size: 566530 Bytes = 553 kB = 0 MB
5200 Load Address: 00000000
5201 Entry Point: 00000000
5202 Verifying Checksum ... OK
5204 => bootm 40100000 40200000
5205 ## Booting Linux kernel at 40100000 ...
5206 Image Name: 2.2.13 for initrd on TQM850L
5207 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5208 Data Size: 335725 Bytes = 327 kB = 0 MB
5209 Load Address: 00000000
5210 Entry Point: 0000000c
5211 Verifying Checksum ... OK
5212 Uncompressing Kernel Image ... OK
5213 ## Loading RAMDisk Image at 40200000 ...
5214 Image Name: Simple Ramdisk Image
5215 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5216 Data Size: 566530 Bytes = 553 kB = 0 MB
5217 Load Address: 00000000
5218 Entry Point: 00000000
5219 Verifying Checksum ... OK
5220 Loading Ramdisk ... OK
5221 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
5222 Boot arguments: root=/dev/ram
5223 time_init: decrementer frequency = 187500000/60
5224 Calibrating delay loop... 49.77 BogoMIPS
5226 RAMDISK: Compressed image found at block 0
5227 VFS: Mounted root (ext2 filesystem).
5231 Boot Linux and pass a flat device tree:
5234 First, U-Boot must be compiled with the appropriate defines. See the section
5235 titled "Linux Kernel Interface" above for a more in depth explanation. The
5236 following is an example of how to start a kernel and pass an updated
5242 oft=oftrees/mpc8540ads.dtb
5243 => tftp $oftaddr $oft
5244 Speed: 1000, full duplex
5246 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5247 Filename 'oftrees/mpc8540ads.dtb'.
5248 Load address: 0x300000
5251 Bytes transferred = 4106 (100a hex)
5252 => tftp $loadaddr $bootfile
5253 Speed: 1000, full duplex
5255 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5257 Load address: 0x200000
5258 Loading:############
5260 Bytes transferred = 1029407 (fb51f hex)
5265 => bootm $loadaddr - $oftaddr
5266 ## Booting image at 00200000 ...
5267 Image Name: Linux-2.6.17-dirty
5268 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5269 Data Size: 1029343 Bytes = 1005.2 kB
5270 Load Address: 00000000
5271 Entry Point: 00000000
5272 Verifying Checksum ... OK
5273 Uncompressing Kernel Image ... OK
5274 Booting using flat device tree at 0x300000
5275 Using MPC85xx ADS machine description
5276 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5280 More About U-Boot Image Types:
5281 ------------------------------
5283 U-Boot supports the following image types:
5285 "Standalone Programs" are directly runnable in the environment
5286 provided by U-Boot; it is expected that (if they behave
5287 well) you can continue to work in U-Boot after return from
5288 the Standalone Program.
5289 "OS Kernel Images" are usually images of some Embedded OS which
5290 will take over control completely. Usually these programs
5291 will install their own set of exception handlers, device
5292 drivers, set up the MMU, etc. - this means, that you cannot
5293 expect to re-enter U-Boot except by resetting the CPU.
5294 "RAMDisk Images" are more or less just data blocks, and their
5295 parameters (address, size) are passed to an OS kernel that is
5297 "Multi-File Images" contain several images, typically an OS
5298 (Linux) kernel image and one or more data images like
5299 RAMDisks. This construct is useful for instance when you want
5300 to boot over the network using BOOTP etc., where the boot
5301 server provides just a single image file, but you want to get
5302 for instance an OS kernel and a RAMDisk image.
5304 "Multi-File Images" start with a list of image sizes, each
5305 image size (in bytes) specified by an "uint32_t" in network
5306 byte order. This list is terminated by an "(uint32_t)0".
5307 Immediately after the terminating 0 follow the images, one by
5308 one, all aligned on "uint32_t" boundaries (size rounded up to
5309 a multiple of 4 bytes).
5311 "Firmware Images" are binary images containing firmware (like
5312 U-Boot or FPGA images) which usually will be programmed to
5315 "Script files" are command sequences that will be executed by
5316 U-Boot's command interpreter; this feature is especially
5317 useful when you configure U-Boot to use a real shell (hush)
5318 as command interpreter.
5320 Booting the Linux zImage:
5321 -------------------------
5323 On some platforms, it's possible to boot Linux zImage. This is done
5324 using the "bootz" command. The syntax of "bootz" command is the same
5325 as the syntax of "bootm" command.
5327 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5328 kernel with raw initrd images. The syntax is slightly different, the
5329 address of the initrd must be augmented by it's size, in the following
5330 format: "<initrd addres>:<initrd size>".
5336 One of the features of U-Boot is that you can dynamically load and
5337 run "standalone" applications, which can use some resources of
5338 U-Boot like console I/O functions or interrupt services.
5340 Two simple examples are included with the sources:
5345 'examples/hello_world.c' contains a small "Hello World" Demo
5346 application; it is automatically compiled when you build U-Boot.
5347 It's configured to run at address 0x00040004, so you can play with it
5351 ## Ready for S-Record download ...
5352 ~>examples/hello_world.srec
5353 1 2 3 4 5 6 7 8 9 10 11 ...
5354 [file transfer complete]
5356 ## Start Addr = 0x00040004
5358 => go 40004 Hello World! This is a test.
5359 ## Starting application at 0x00040004 ...
5370 Hit any key to exit ...
5372 ## Application terminated, rc = 0x0
5374 Another example, which demonstrates how to register a CPM interrupt
5375 handler with the U-Boot code, can be found in 'examples/timer.c'.
5376 Here, a CPM timer is set up to generate an interrupt every second.
5377 The interrupt service routine is trivial, just printing a '.'
5378 character, but this is just a demo program. The application can be
5379 controlled by the following keys:
5381 ? - print current values og the CPM Timer registers
5382 b - enable interrupts and start timer
5383 e - stop timer and disable interrupts
5384 q - quit application
5387 ## Ready for S-Record download ...
5388 ~>examples/timer.srec
5389 1 2 3 4 5 6 7 8 9 10 11 ...
5390 [file transfer complete]
5392 ## Start Addr = 0x00040004
5395 ## Starting application at 0x00040004 ...
5398 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5401 [q, b, e, ?] Set interval 1000000 us
5404 [q, b, e, ?] ........
5405 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5408 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5411 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5414 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5416 [q, b, e, ?] ...Stopping timer
5418 [q, b, e, ?] ## Application terminated, rc = 0x0
5424 Over time, many people have reported problems when trying to use the
5425 "minicom" terminal emulation program for serial download. I (wd)
5426 consider minicom to be broken, and recommend not to use it. Under
5427 Unix, I recommend to use C-Kermit for general purpose use (and
5428 especially for kermit binary protocol download ("loadb" command), and
5429 use "cu" for S-Record download ("loads" command). See
5430 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5431 for help with kermit.
5434 Nevertheless, if you absolutely want to use it try adding this
5435 configuration to your "File transfer protocols" section:
5437 Name Program Name U/D FullScr IO-Red. Multi
5438 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5439 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5445 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5446 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5448 Building requires a cross environment; it is known to work on
5449 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5450 need gmake since the Makefiles are not compatible with BSD make).
5451 Note that the cross-powerpc package does not install include files;
5452 attempting to build U-Boot will fail because <machine/ansi.h> is
5453 missing. This file has to be installed and patched manually:
5455 # cd /usr/pkg/cross/powerpc-netbsd/include
5457 # ln -s powerpc machine
5458 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5459 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5461 Native builds *don't* work due to incompatibilities between native
5462 and U-Boot include files.
5464 Booting assumes that (the first part of) the image booted is a
5465 stage-2 loader which in turn loads and then invokes the kernel
5466 proper. Loader sources will eventually appear in the NetBSD source
5467 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5468 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5471 Implementation Internals:
5472 =========================
5474 The following is not intended to be a complete description of every
5475 implementation detail. However, it should help to understand the
5476 inner workings of U-Boot and make it easier to port it to custom
5480 Initial Stack, Global Data:
5481 ---------------------------
5483 The implementation of U-Boot is complicated by the fact that U-Boot
5484 starts running out of ROM (flash memory), usually without access to
5485 system RAM (because the memory controller is not initialized yet).
5486 This means that we don't have writable Data or BSS segments, and BSS
5487 is not initialized as zero. To be able to get a C environment working
5488 at all, we have to allocate at least a minimal stack. Implementation
5489 options for this are defined and restricted by the CPU used: Some CPU
5490 models provide on-chip memory (like the IMMR area on MPC8xx and
5491 MPC826x processors), on others (parts of) the data cache can be
5492 locked as (mis-) used as memory, etc.
5494 Chris Hallinan posted a good summary of these issues to the
5495 U-Boot mailing list:
5497 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5498 From: "Chris Hallinan" <clh@net1plus.com>
5499 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5502 Correct me if I'm wrong, folks, but the way I understand it
5503 is this: Using DCACHE as initial RAM for Stack, etc, does not
5504 require any physical RAM backing up the cache. The cleverness
5505 is that the cache is being used as a temporary supply of
5506 necessary storage before the SDRAM controller is setup. It's
5507 beyond the scope of this list to explain the details, but you
5508 can see how this works by studying the cache architecture and
5509 operation in the architecture and processor-specific manuals.
5511 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5512 is another option for the system designer to use as an
5513 initial stack/RAM area prior to SDRAM being available. Either
5514 option should work for you. Using CS 4 should be fine if your
5515 board designers haven't used it for something that would
5516 cause you grief during the initial boot! It is frequently not
5519 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5520 with your processor/board/system design. The default value
5521 you will find in any recent u-boot distribution in
5522 walnut.h should work for you. I'd set it to a value larger
5523 than your SDRAM module. If you have a 64MB SDRAM module, set
5524 it above 400_0000. Just make sure your board has no resources
5525 that are supposed to respond to that address! That code in
5526 start.S has been around a while and should work as is when
5527 you get the config right.
5532 It is essential to remember this, since it has some impact on the C
5533 code for the initialization procedures:
5535 * Initialized global data (data segment) is read-only. Do not attempt
5538 * Do not use any uninitialized global data (or implicitely initialized
5539 as zero data - BSS segment) at all - this is undefined, initiali-
5540 zation is performed later (when relocating to RAM).
5542 * Stack space is very limited. Avoid big data buffers or things like
5545 Having only the stack as writable memory limits means we cannot use
5546 normal global data to share information beween the code. But it
5547 turned out that the implementation of U-Boot can be greatly
5548 simplified by making a global data structure (gd_t) available to all
5549 functions. We could pass a pointer to this data as argument to _all_
5550 functions, but this would bloat the code. Instead we use a feature of
5551 the GCC compiler (Global Register Variables) to share the data: we
5552 place a pointer (gd) to the global data into a register which we
5553 reserve for this purpose.
5555 When choosing a register for such a purpose we are restricted by the
5556 relevant (E)ABI specifications for the current architecture, and by
5557 GCC's implementation.
5559 For PowerPC, the following registers have specific use:
5561 R2: reserved for system use
5562 R3-R4: parameter passing and return values
5563 R5-R10: parameter passing
5564 R13: small data area pointer
5568 (U-Boot also uses R12 as internal GOT pointer. r12
5569 is a volatile register so r12 needs to be reset when
5570 going back and forth between asm and C)
5572 ==> U-Boot will use R2 to hold a pointer to the global data
5574 Note: on PPC, we could use a static initializer (since the
5575 address of the global data structure is known at compile time),
5576 but it turned out that reserving a register results in somewhat
5577 smaller code - although the code savings are not that big (on
5578 average for all boards 752 bytes for the whole U-Boot image,
5579 624 text + 127 data).
5581 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5582 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5584 ==> U-Boot will use P3 to hold a pointer to the global data
5586 On ARM, the following registers are used:
5588 R0: function argument word/integer result
5589 R1-R3: function argument word
5590 R9: platform specific
5591 R10: stack limit (used only if stack checking is enabled)
5592 R11: argument (frame) pointer
5593 R12: temporary workspace
5596 R15: program counter
5598 ==> U-Boot will use R9 to hold a pointer to the global data
5600 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
5602 On Nios II, the ABI is documented here:
5603 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5605 ==> U-Boot will use gp to hold a pointer to the global data
5607 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5608 to access small data sections, so gp is free.
5610 On NDS32, the following registers are used:
5612 R0-R1: argument/return
5614 R15: temporary register for assembler
5615 R16: trampoline register
5616 R28: frame pointer (FP)
5617 R29: global pointer (GP)
5618 R30: link register (LP)
5619 R31: stack pointer (SP)
5620 PC: program counter (PC)
5622 ==> U-Boot will use R10 to hold a pointer to the global data
5624 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5625 or current versions of GCC may "optimize" the code too much.
5630 U-Boot runs in system state and uses physical addresses, i.e. the
5631 MMU is not used either for address mapping nor for memory protection.
5633 The available memory is mapped to fixed addresses using the memory
5634 controller. In this process, a contiguous block is formed for each
5635 memory type (Flash, SDRAM, SRAM), even when it consists of several
5636 physical memory banks.
5638 U-Boot is installed in the first 128 kB of the first Flash bank (on
5639 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5640 booting and sizing and initializing DRAM, the code relocates itself
5641 to the upper end of DRAM. Immediately below the U-Boot code some
5642 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5643 configuration setting]. Below that, a structure with global Board
5644 Info data is placed, followed by the stack (growing downward).
5646 Additionally, some exception handler code is copied to the low 8 kB
5647 of DRAM (0x00000000 ... 0x00001FFF).
5649 So a typical memory configuration with 16 MB of DRAM could look like
5652 0x0000 0000 Exception Vector code
5655 0x0000 2000 Free for Application Use
5661 0x00FB FF20 Monitor Stack (Growing downward)
5662 0x00FB FFAC Board Info Data and permanent copy of global data
5663 0x00FC 0000 Malloc Arena
5666 0x00FE 0000 RAM Copy of Monitor Code
5667 ... eventually: LCD or video framebuffer
5668 ... eventually: pRAM (Protected RAM - unchanged by reset)
5669 0x00FF FFFF [End of RAM]
5672 System Initialization:
5673 ----------------------
5675 In the reset configuration, U-Boot starts at the reset entry point
5676 (on most PowerPC systems at address 0x00000100). Because of the reset
5677 configuration for CS0# this is a mirror of the onboard Flash memory.
5678 To be able to re-map memory U-Boot then jumps to its link address.
5679 To be able to implement the initialization code in C, a (small!)
5680 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5681 which provide such a feature like MPC8xx or MPC8260), or in a locked
5682 part of the data cache. After that, U-Boot initializes the CPU core,
5683 the caches and the SIU.
5685 Next, all (potentially) available memory banks are mapped using a
5686 preliminary mapping. For example, we put them on 512 MB boundaries
5687 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5688 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5689 programmed for SDRAM access. Using the temporary configuration, a
5690 simple memory test is run that determines the size of the SDRAM
5693 When there is more than one SDRAM bank, and the banks are of
5694 different size, the largest is mapped first. For equal size, the first
5695 bank (CS2#) is mapped first. The first mapping is always for address
5696 0x00000000, with any additional banks following immediately to create
5697 contiguous memory starting from 0.
5699 Then, the monitor installs itself at the upper end of the SDRAM area
5700 and allocates memory for use by malloc() and for the global Board
5701 Info data; also, the exception vector code is copied to the low RAM
5702 pages, and the final stack is set up.
5704 Only after this relocation will you have a "normal" C environment;
5705 until that you are restricted in several ways, mostly because you are
5706 running from ROM, and because the code will have to be relocated to a
5710 U-Boot Porting Guide:
5711 ----------------------
5713 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5717 int main(int argc, char *argv[])
5719 sighandler_t no_more_time;
5721 signal(SIGALRM, no_more_time);
5722 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5724 if (available_money > available_manpower) {
5725 Pay consultant to port U-Boot;
5729 Download latest U-Boot source;
5731 Subscribe to u-boot mailing list;
5734 email("Hi, I am new to U-Boot, how do I get started?");
5737 Read the README file in the top level directory;
5738 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5739 Read applicable doc/*.README;
5740 Read the source, Luke;
5741 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5744 if (available_money > toLocalCurrency ($2500))
5747 Add a lot of aggravation and time;
5749 if (a similar board exists) { /* hopefully... */
5750 cp -a board/<similar> board/<myboard>
5751 cp include/configs/<similar>.h include/configs/<myboard>.h
5753 Create your own board support subdirectory;
5754 Create your own board include/configs/<myboard>.h file;
5756 Edit new board/<myboard> files
5757 Edit new include/configs/<myboard>.h
5762 Add / modify source code;
5766 email("Hi, I am having problems...");
5768 Send patch file to the U-Boot email list;
5769 if (reasonable critiques)
5770 Incorporate improvements from email list code review;
5772 Defend code as written;
5778 void no_more_time (int sig)
5787 All contributions to U-Boot should conform to the Linux kernel
5788 coding style; see the file "Documentation/CodingStyle" and the script
5789 "scripts/Lindent" in your Linux kernel source directory.
5791 Source files originating from a different project (for example the
5792 MTD subsystem) are generally exempt from these guidelines and are not
5793 reformated to ease subsequent migration to newer versions of those
5796 Please note that U-Boot is implemented in C (and to some small parts in
5797 Assembler); no C++ is used, so please do not use C++ style comments (//)
5800 Please also stick to the following formatting rules:
5801 - remove any trailing white space
5802 - use TAB characters for indentation and vertical alignment, not spaces
5803 - make sure NOT to use DOS '\r\n' line feeds
5804 - do not add more than 2 consecutive empty lines to source files
5805 - do not add trailing empty lines to source files
5807 Submissions which do not conform to the standards may be returned
5808 with a request to reformat the changes.
5814 Since the number of patches for U-Boot is growing, we need to
5815 establish some rules. Submissions which do not conform to these rules
5816 may be rejected, even when they contain important and valuable stuff.
5818 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5820 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5821 see http://lists.denx.de/mailman/listinfo/u-boot
5823 When you send a patch, please include the following information with
5826 * For bug fixes: a description of the bug and how your patch fixes
5827 this bug. Please try to include a way of demonstrating that the
5828 patch actually fixes something.
5830 * For new features: a description of the feature and your
5833 * A CHANGELOG entry as plaintext (separate from the patch)
5835 * For major contributions, your entry to the CREDITS file
5837 * When you add support for a new board, don't forget to add a
5838 maintainer e-mail address to the boards.cfg file, too.
5840 * If your patch adds new configuration options, don't forget to
5841 document these in the README file.
5843 * The patch itself. If you are using git (which is *strongly*
5844 recommended) you can easily generate the patch using the
5845 "git format-patch". If you then use "git send-email" to send it to
5846 the U-Boot mailing list, you will avoid most of the common problems
5847 with some other mail clients.
5849 If you cannot use git, use "diff -purN OLD NEW". If your version of
5850 diff does not support these options, then get the latest version of
5853 The current directory when running this command shall be the parent
5854 directory of the U-Boot source tree (i. e. please make sure that
5855 your patch includes sufficient directory information for the
5858 We prefer patches as plain text. MIME attachments are discouraged,
5859 and compressed attachments must not be used.
5861 * If one logical set of modifications affects or creates several
5862 files, all these changes shall be submitted in a SINGLE patch file.
5864 * Changesets that contain different, unrelated modifications shall be
5865 submitted as SEPARATE patches, one patch per changeset.
5870 * Before sending the patch, run the MAKEALL script on your patched
5871 source tree and make sure that no errors or warnings are reported
5872 for any of the boards.
5874 * Keep your modifications to the necessary minimum: A patch
5875 containing several unrelated changes or arbitrary reformats will be
5876 returned with a request to re-formatting / split it.
5878 * If you modify existing code, make sure that your new code does not
5879 add to the memory footprint of the code ;-) Small is beautiful!
5880 When adding new features, these should compile conditionally only
5881 (using #ifdef), and the resulting code with the new feature
5882 disabled must not need more memory than the old code without your
5885 * Remember that there is a size limit of 100 kB per message on the
5886 u-boot mailing list. Bigger patches will be moderated. If they are
5887 reasonable and not too big, they will be acknowledged. But patches
5888 bigger than the size limit should be avoided.
projects / platform / kernel / u-boot.git / blob