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 /arm926ejs Files specific to ARM 926 CPUs
143 /arm1136 Files specific to ARM 1136 CPUs
144 /ixp Files specific to Intel XScale IXP CPUs
145 /pxa Files specific to Intel XScale PXA CPUs
146 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
147 /lib Architecture specific library files
148 /avr32 Files generic to AVR32 architecture
149 /cpu CPU specific files
150 /lib Architecture specific library files
151 /blackfin Files generic to Analog Devices Blackfin architecture
152 /cpu CPU specific files
153 /lib Architecture specific library files
154 /x86 Files generic to x86 architecture
155 /cpu CPU specific files
156 /lib Architecture specific library files
157 /m68k Files generic to m68k architecture
158 /cpu CPU specific files
159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
164 /lib Architecture specific library files
165 /microblaze Files generic to microblaze architecture
166 /cpu CPU specific files
167 /lib Architecture specific library files
168 /mips Files generic to MIPS architecture
169 /cpu CPU specific files
170 /mips32 Files specific to MIPS32 CPUs
171 /xburst Files specific to Ingenic XBurst CPUs
172 /lib Architecture specific library files
173 /nds32 Files generic to NDS32 architecture
174 /cpu CPU specific files
175 /n1213 Files specific to Andes Technology N1213 CPUs
176 /lib Architecture specific library files
177 /nios2 Files generic to Altera NIOS2 architecture
178 /cpu CPU specific files
179 /lib Architecture specific library files
180 /powerpc Files generic to PowerPC architecture
181 /cpu CPU specific files
182 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
183 /mpc5xx Files specific to Freescale MPC5xx CPUs
184 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
185 /mpc8xx Files specific to Freescale MPC8xx CPUs
186 /mpc824x Files specific to Freescale MPC824x CPUs
187 /mpc8260 Files specific to Freescale MPC8260 CPUs
188 /mpc85xx Files specific to Freescale MPC85xx CPUs
189 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
190 /lib Architecture specific library files
191 /sh Files generic to SH architecture
192 /cpu CPU specific files
193 /sh2 Files specific to sh2 CPUs
194 /sh3 Files specific to sh3 CPUs
195 /sh4 Files specific to sh4 CPUs
196 /lib Architecture specific library files
197 /sparc Files generic to SPARC architecture
198 /cpu CPU specific files
199 /leon2 Files specific to Gaisler LEON2 SPARC CPU
200 /leon3 Files specific to Gaisler LEON3 SPARC CPU
201 /lib Architecture specific library files
202 /api Machine/arch independent API for external apps
203 /board Board dependent files
204 /common Misc architecture independent functions
205 /disk Code for disk drive partition handling
206 /doc Documentation (don't expect too much)
207 /drivers Commonly used device drivers
208 /examples Example code for standalone applications, etc.
209 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
210 /include Header Files
211 /lib Files generic to all architectures
212 /libfdt Library files to support flattened device trees
213 /lzma Library files to support LZMA decompression
214 /lzo Library files to support LZO decompression
216 /post Power On Self Test
217 /rtc Real Time Clock drivers
218 /tools Tools to build S-Record or U-Boot images, etc.
220 Software Configuration:
221 =======================
223 Configuration is usually done using C preprocessor defines; the
224 rationale behind that is to avoid dead code whenever possible.
226 There are two classes of configuration variables:
228 * Configuration _OPTIONS_:
229 These are selectable by the user and have names beginning with
232 * Configuration _SETTINGS_:
233 These depend on the hardware etc. and should not be meddled with if
234 you don't know what you're doing; they have names beginning with
237 Later we will add a configuration tool - probably similar to or even
238 identical to what's used for the Linux kernel. Right now, we have to
239 do the configuration by hand, which means creating some symbolic
240 links and editing some configuration files. We use the TQM8xxL boards
244 Selection of Processor Architecture and Board Type:
245 ---------------------------------------------------
247 For all supported boards there are ready-to-use default
248 configurations available; just type "make <board_name>_config".
250 Example: For a TQM823L module type:
255 For the Cogent platform, you need to specify the CPU type as well;
256 e.g. "make cogent_mpc8xx_config". And also configure the cogent
257 directory according to the instructions in cogent/README.
260 Configuration Options:
261 ----------------------
263 Configuration depends on the combination of board and CPU type; all
264 such information is kept in a configuration file
265 "include/configs/<board_name>.h".
267 Example: For a TQM823L module, all configuration settings are in
268 "include/configs/TQM823L.h".
271 Many of the options are named exactly as the corresponding Linux
272 kernel configuration options. The intention is to make it easier to
273 build a config tool - later.
276 The following options need to be configured:
278 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
280 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
282 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
283 Define exactly one, e.g. CONFIG_ATSTK1002
285 - CPU Module Type: (if CONFIG_COGENT is defined)
286 Define exactly one of
288 --- FIXME --- not tested yet:
289 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
290 CONFIG_CMA287_23, CONFIG_CMA287_50
292 - Motherboard Type: (if CONFIG_COGENT is defined)
293 Define exactly one of
294 CONFIG_CMA101, CONFIG_CMA102
296 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
297 Define one or more of
300 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
301 Define one or more of
302 CONFIG_LCD_HEARTBEAT - update a character position on
303 the LCD display every second with
306 - Board flavour: (if CONFIG_MPC8260ADS is defined)
309 CONFIG_SYS_8260ADS - original MPC8260ADS
310 CONFIG_SYS_8266ADS - MPC8266ADS
311 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
312 CONFIG_SYS_8272ADS - MPC8272ADS
314 - Marvell Family Member
315 CONFIG_SYS_MVFS - define it if you want to enable
316 multiple fs option at one time
317 for marvell soc family
319 - MPC824X Family Member (if CONFIG_MPC824X is defined)
320 Define exactly one of
321 CONFIG_MPC8240, CONFIG_MPC8245
323 - 8xx CPU Options: (if using an MPC8xx CPU)
324 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
325 get_gclk_freq() cannot work
326 e.g. if there is no 32KHz
327 reference PIT/RTC clock
328 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
331 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
332 CONFIG_SYS_8xx_CPUCLK_MIN
333 CONFIG_SYS_8xx_CPUCLK_MAX
334 CONFIG_8xx_CPUCLK_DEFAULT
335 See doc/README.MPC866
337 CONFIG_SYS_MEASURE_CPUCLK
339 Define this to measure the actual CPU clock instead
340 of relying on the correctness of the configured
341 values. Mostly useful for board bringup to make sure
342 the PLL is locked at the intended frequency. Note
343 that this requires a (stable) reference clock (32 kHz
344 RTC clock or CONFIG_SYS_8XX_XIN)
346 CONFIG_SYS_DELAYED_ICACHE
348 Define this option if you want to enable the
349 ICache only when Code runs from RAM.
354 Specifies that the core is a 64-bit PowerPC implementation (implements
355 the "64" category of the Power ISA). This is necessary for ePAPR
356 compliance, among other possible reasons.
358 CONFIG_SYS_FSL_TBCLK_DIV
360 Defines the core time base clock divider ratio compared to the
361 system clock. On most PQ3 devices this is 8, on newer QorIQ
362 devices it can be 16 or 32. The ratio varies from SoC to Soc.
364 CONFIG_SYS_FSL_PCIE_COMPAT
366 Defines the string to utilize when trying to match PCIe device
367 tree nodes for the given platform.
369 CONFIG_SYS_PPC_E500_DEBUG_TLB
371 Enables a temporary TLB entry to be used during boot to work
372 around limitations in e500v1 and e500v2 external debugger
373 support. This reduces the portions of the boot code where
374 breakpoints and single stepping do not work. The value of this
375 symbol should be set to the TLB1 entry to be used for this
378 CONFIG_SYS_FSL_ERRATUM_A004510
380 Enables a workaround for erratum A004510. If set,
381 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
382 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
385 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
387 Defines one or two SoC revisions (low 8 bits of SVR)
388 for which the A004510 workaround should be applied.
390 The rest of SVR is either not relevant to the decision
391 of whether the erratum is present (e.g. p2040 versus
392 p2041) or is implied by the build target, which controls
393 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
395 See Freescale App Note 4493 for more information about
398 CONFIG_A003399_NOR_WORKAROUND
399 Enables a workaround for IFC erratum A003399. It is only
400 requred during NOR boot.
402 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
404 This is the value to write into CCSR offset 0x18600
405 according to the A004510 workaround.
407 CONFIG_SYS_FSL_DSP_DDR_ADDR
408 This value denotes start offset of DDR memory which is
409 connected exclusively to the DSP cores.
411 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
412 This value denotes start offset of M2 memory
413 which is directly connected to the DSP core.
415 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
416 This value denotes start offset of M3 memory which is directly
417 connected to the DSP core.
419 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
420 This value denotes start offset of DSP CCSR space.
422 CONFIG_SYS_FSL_DDR_EMU
423 Specify emulator support for DDR. Some DDR features such as
424 deskew training are not available.
426 - Generic CPU options:
427 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
429 Defines the endianess of the CPU. Implementation of those
430 values is arch specific.
432 - Intel Monahans options:
433 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
435 Defines the Monahans run mode to oscillator
436 ratio. Valid values are 8, 16, 24, 31. The core
437 frequency is this value multiplied by 13 MHz.
439 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
441 Defines the Monahans turbo mode to oscillator
442 ratio. Valid values are 1 (default if undefined) and
443 2. The core frequency as calculated above is multiplied
447 CONFIG_SYS_INIT_SP_OFFSET
449 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
450 pointer. This is needed for the temporary stack before
453 CONFIG_SYS_MIPS_CACHE_MODE
455 Cache operation mode for the MIPS CPU.
456 See also arch/mips/include/asm/mipsregs.h.
458 CONF_CM_CACHABLE_NO_WA
461 CONF_CM_CACHABLE_NONCOHERENT
465 CONF_CM_CACHABLE_ACCELERATED
467 CONFIG_SYS_XWAY_EBU_BOOTCFG
469 Special option for Lantiq XWAY SoCs for booting from NOR flash.
470 See also arch/mips/cpu/mips32/start.S.
472 CONFIG_XWAY_SWAP_BYTES
474 Enable compilation of tools/xway-swap-bytes needed for Lantiq
475 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
476 be swapped if a flash programmer is used.
479 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
481 Select high exception vectors of the ARM core, e.g., do not
482 clear the V bit of the c1 register of CP15.
484 CONFIG_SYS_THUMB_BUILD
486 Use this flag to build U-Boot using the Thumb instruction
487 set for ARM architectures. Thumb instruction set provides
488 better code density. For ARM architectures that support
489 Thumb2 this flag will result in Thumb2 code generated by
492 CONFIG_ARM_ERRATA_716044
493 CONFIG_ARM_ERRATA_742230
494 CONFIG_ARM_ERRATA_743622
495 CONFIG_ARM_ERRATA_751472
497 If set, the workarounds for these ARM errata are applied early
498 during U-Boot startup. Note that these options force the
499 workarounds to be applied; no CPU-type/version detection
500 exists, unlike the similar options in the Linux kernel. Do not
501 set these options unless they apply!
506 The frequency of the timer returned by get_timer().
507 get_timer() must operate in milliseconds and this CONFIG
508 option must be set to 1000.
510 - Linux Kernel Interface:
513 U-Boot stores all clock information in Hz
514 internally. For binary compatibility with older Linux
515 kernels (which expect the clocks passed in the
516 bd_info data to be in MHz) the environment variable
517 "clocks_in_mhz" can be defined so that U-Boot
518 converts clock data to MHZ before passing it to the
520 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
521 "clocks_in_mhz=1" is automatically included in the
524 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
526 When transferring memsize parameter to linux, some versions
527 expect it to be in bytes, others in MB.
528 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
532 New kernel versions are expecting firmware settings to be
533 passed using flattened device trees (based on open firmware
537 * New libfdt-based support
538 * Adds the "fdt" command
539 * The bootm command automatically updates the fdt
541 OF_CPU - The proper name of the cpus node (only required for
542 MPC512X and MPC5xxx based boards).
543 OF_SOC - The proper name of the soc node (only required for
544 MPC512X and MPC5xxx based boards).
545 OF_TBCLK - The timebase frequency.
546 OF_STDOUT_PATH - The path to the console device
548 boards with QUICC Engines require OF_QE to set UCC MAC
551 CONFIG_OF_BOARD_SETUP
553 Board code has addition modification that it wants to make
554 to the flat device tree before handing it off to the kernel
558 This define fills in the correct boot CPU in the boot
559 param header, the default value is zero if undefined.
563 U-Boot can detect if an IDE device is present or not.
564 If not, and this new config option is activated, U-Boot
565 removes the ATA node from the DTS before booting Linux,
566 so the Linux IDE driver does not probe the device and
567 crash. This is needed for buggy hardware (uc101) where
568 no pull down resistor is connected to the signal IDE5V_DD7.
570 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
572 This setting is mandatory for all boards that have only one
573 machine type and must be used to specify the machine type
574 number as it appears in the ARM machine registry
575 (see http://www.arm.linux.org.uk/developer/machines/).
576 Only boards that have multiple machine types supported
577 in a single configuration file and the machine type is
578 runtime discoverable, do not have to use this setting.
580 - vxWorks boot parameters:
582 bootvx constructs a valid bootline using the following
583 environments variables: bootfile, ipaddr, serverip, hostname.
584 It loads the vxWorks image pointed bootfile.
586 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
587 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
588 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
589 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
591 CONFIG_SYS_VXWORKS_ADD_PARAMS
593 Add it at the end of the bootline. E.g "u=username pw=secret"
595 Note: If a "bootargs" environment is defined, it will overwride
596 the defaults discussed just above.
598 - Cache Configuration:
599 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
600 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
601 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
603 - Cache Configuration for ARM:
604 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
606 CONFIG_SYS_PL310_BASE - Physical base address of PL310
607 controller register space
612 Define this if you want support for Amba PrimeCell PL010 UARTs.
616 Define this if you want support for Amba PrimeCell PL011 UARTs.
620 If you have Amba PrimeCell PL011 UARTs, set this variable to
621 the clock speed of the UARTs.
625 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
626 define this to a list of base addresses for each (supported)
627 port. See e.g. include/configs/versatile.h
629 CONFIG_PL011_SERIAL_RLCR
631 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
632 have separate receive and transmit line control registers. Set
633 this variable to initialize the extra register.
635 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
637 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
638 boot loader that has already initialized the UART. Define this
639 variable to flush the UART at init time.
643 Depending on board, define exactly one serial port
644 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
645 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
646 console by defining CONFIG_8xx_CONS_NONE
648 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
649 port routines must be defined elsewhere
650 (i.e. serial_init(), serial_getc(), ...)
653 Enables console device for a color framebuffer. Needs following
654 defines (cf. smiLynxEM, i8042)
655 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
657 VIDEO_HW_RECTFILL graphic chip supports
660 VIDEO_HW_BITBLT graphic chip supports
661 bit-blit (cf. smiLynxEM)
662 VIDEO_VISIBLE_COLS visible pixel columns
664 VIDEO_VISIBLE_ROWS visible pixel rows
665 VIDEO_PIXEL_SIZE bytes per pixel
666 VIDEO_DATA_FORMAT graphic data format
667 (0-5, cf. cfb_console.c)
668 VIDEO_FB_ADRS framebuffer address
669 VIDEO_KBD_INIT_FCT keyboard int fct
670 (i.e. i8042_kbd_init())
671 VIDEO_TSTC_FCT test char fct
673 VIDEO_GETC_FCT get char fct
675 CONFIG_CONSOLE_CURSOR cursor drawing on/off
676 (requires blink timer
678 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
679 CONFIG_CONSOLE_TIME display time/date info in
681 (requires CONFIG_CMD_DATE)
682 CONFIG_VIDEO_LOGO display Linux logo in
684 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
685 linux_logo.h for logo.
686 Requires CONFIG_VIDEO_LOGO
687 CONFIG_CONSOLE_EXTRA_INFO
688 additional board info beside
691 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
692 a limited number of ANSI escape sequences (cursor control,
693 erase functions and limited graphics rendition control).
695 When CONFIG_CFB_CONSOLE is defined, video console is
696 default i/o. Serial console can be forced with
697 environment 'console=serial'.
699 When CONFIG_SILENT_CONSOLE is defined, all console
700 messages (by U-Boot and Linux!) can be silenced with
701 the "silent" environment variable. See
702 doc/README.silent for more information.
705 CONFIG_BAUDRATE - in bps
706 Select one of the baudrates listed in
707 CONFIG_SYS_BAUDRATE_TABLE, see below.
708 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
710 - Console Rx buffer length
711 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
712 the maximum receive buffer length for the SMC.
713 This option is actual only for 82xx and 8xx possible.
714 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
715 must be defined, to setup the maximum idle timeout for
718 - Pre-Console Buffer:
719 Prior to the console being initialised (i.e. serial UART
720 initialised etc) all console output is silently discarded.
721 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
722 buffer any console messages prior to the console being
723 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
724 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
725 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
726 bytes are output before the console is initialised, the
727 earlier bytes are discarded.
729 'Sane' compilers will generate smaller code if
730 CONFIG_PRE_CON_BUF_SZ is a power of 2
732 - Safe printf() functions
733 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
734 the printf() functions. These are defined in
735 include/vsprintf.h and include snprintf(), vsnprintf() and
736 so on. Code size increase is approximately 300-500 bytes.
737 If this option is not given then these functions will
738 silently discard their buffer size argument - this means
739 you are not getting any overflow checking in this case.
741 - Boot Delay: CONFIG_BOOTDELAY - in seconds
742 Delay before automatically booting the default image;
743 set to -1 to disable autoboot.
744 set to -2 to autoboot with no delay and not check for abort
745 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
747 See doc/README.autoboot for these options that
748 work with CONFIG_BOOTDELAY. None are required.
749 CONFIG_BOOT_RETRY_TIME
750 CONFIG_BOOT_RETRY_MIN
751 CONFIG_AUTOBOOT_KEYED
752 CONFIG_AUTOBOOT_PROMPT
753 CONFIG_AUTOBOOT_DELAY_STR
754 CONFIG_AUTOBOOT_STOP_STR
755 CONFIG_AUTOBOOT_DELAY_STR2
756 CONFIG_AUTOBOOT_STOP_STR2
757 CONFIG_ZERO_BOOTDELAY_CHECK
758 CONFIG_RESET_TO_RETRY
762 Only needed when CONFIG_BOOTDELAY is enabled;
763 define a command string that is automatically executed
764 when no character is read on the console interface
765 within "Boot Delay" after reset.
768 This can be used to pass arguments to the bootm
769 command. The value of CONFIG_BOOTARGS goes into the
770 environment value "bootargs".
772 CONFIG_RAMBOOT and CONFIG_NFSBOOT
773 The value of these goes into the environment as
774 "ramboot" and "nfsboot" respectively, and can be used
775 as a convenience, when switching between booting from
781 When this option is #defined, the existence of the
782 environment variable "preboot" will be checked
783 immediately before starting the CONFIG_BOOTDELAY
784 countdown and/or running the auto-boot command resp.
785 entering interactive mode.
787 This feature is especially useful when "preboot" is
788 automatically generated or modified. For an example
789 see the LWMON board specific code: here "preboot" is
790 modified when the user holds down a certain
791 combination of keys on the (special) keyboard when
794 - Serial Download Echo Mode:
796 If defined to 1, all characters received during a
797 serial download (using the "loads" command) are
798 echoed back. This might be needed by some terminal
799 emulations (like "cu"), but may as well just take
800 time on others. This setting #define's the initial
801 value of the "loads_echo" environment variable.
803 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
805 Select one of the baudrates listed in
806 CONFIG_SYS_BAUDRATE_TABLE, see below.
809 Monitor commands can be included or excluded
810 from the build by using the #include files
811 <config_cmd_all.h> and #undef'ing unwanted
812 commands, or using <config_cmd_default.h>
813 and augmenting with additional #define's
816 The default command configuration includes all commands
817 except those marked below with a "*".
819 CONFIG_CMD_ASKENV * ask for env variable
820 CONFIG_CMD_BDI bdinfo
821 CONFIG_CMD_BEDBUG * Include BedBug Debugger
822 CONFIG_CMD_BMP * BMP support
823 CONFIG_CMD_BSP * Board specific commands
824 CONFIG_CMD_BOOTD bootd
825 CONFIG_CMD_CACHE * icache, dcache
826 CONFIG_CMD_CONSOLE coninfo
827 CONFIG_CMD_CRC32 * crc32
828 CONFIG_CMD_DATE * support for RTC, date/time...
829 CONFIG_CMD_DHCP * DHCP support
830 CONFIG_CMD_DIAG * Diagnostics
831 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
832 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
833 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
834 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
835 CONFIG_CMD_DTT * Digital Therm and Thermostat
836 CONFIG_CMD_ECHO echo arguments
837 CONFIG_CMD_EDITENV edit env variable
838 CONFIG_CMD_EEPROM * EEPROM read/write support
839 CONFIG_CMD_ELF * bootelf, bootvx
840 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
841 CONFIG_CMD_ENV_FLAGS * display details about env flags
842 CONFIG_CMD_EXPORTENV * export the environment
843 CONFIG_CMD_EXT2 * ext2 command support
844 CONFIG_CMD_EXT4 * ext4 command support
845 CONFIG_CMD_SAVEENV saveenv
846 CONFIG_CMD_FDC * Floppy Disk Support
847 CONFIG_CMD_FAT * FAT command support
848 CONFIG_CMD_FDOS * Dos diskette Support
849 CONFIG_CMD_FLASH flinfo, erase, protect
850 CONFIG_CMD_FPGA FPGA device initialization support
851 CONFIG_CMD_FUSE * Device fuse support
852 CONFIG_CMD_GETTIME * Get time since boot
853 CONFIG_CMD_GO * the 'go' command (exec code)
854 CONFIG_CMD_GREPENV * search environment
855 CONFIG_CMD_HASH * calculate hash / digest
856 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
857 CONFIG_CMD_I2C * I2C serial bus support
858 CONFIG_CMD_IDE * IDE harddisk support
859 CONFIG_CMD_IMI iminfo
860 CONFIG_CMD_IMLS List all images found in NOR flash
861 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
862 CONFIG_CMD_IMMAP * IMMR dump support
863 CONFIG_CMD_IMPORTENV * import an environment
864 CONFIG_CMD_INI * import data from an ini file into the env
865 CONFIG_CMD_IRQ * irqinfo
866 CONFIG_CMD_ITEST Integer/string test of 2 values
867 CONFIG_CMD_JFFS2 * JFFS2 Support
868 CONFIG_CMD_KGDB * kgdb
869 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
870 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
872 CONFIG_CMD_LOADB loadb
873 CONFIG_CMD_LOADS loads
874 CONFIG_CMD_MD5SUM * print md5 message digest
875 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
876 CONFIG_CMD_MEMINFO * Display detailed memory information
877 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
879 CONFIG_CMD_MEMTEST * mtest
880 CONFIG_CMD_MISC Misc functions like sleep etc
881 CONFIG_CMD_MMC * MMC memory mapped support
882 CONFIG_CMD_MII * MII utility commands
883 CONFIG_CMD_MTDPARTS * MTD partition support
884 CONFIG_CMD_NAND * NAND support
885 CONFIG_CMD_NET bootp, tftpboot, rarpboot
886 CONFIG_CMD_NFS NFS support
887 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
888 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
889 CONFIG_CMD_PCI * pciinfo
890 CONFIG_CMD_PCMCIA * PCMCIA support
891 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
893 CONFIG_CMD_PORTIO * Port I/O
894 CONFIG_CMD_READ * Read raw data from partition
895 CONFIG_CMD_REGINFO * Register dump
896 CONFIG_CMD_RUN run command in env variable
897 CONFIG_CMD_SANDBOX * sb command to access sandbox features
898 CONFIG_CMD_SAVES * save S record dump
899 CONFIG_CMD_SCSI * SCSI Support
900 CONFIG_CMD_SDRAM * print SDRAM configuration information
901 (requires CONFIG_CMD_I2C)
902 CONFIG_CMD_SETGETDCR Support for DCR Register access
904 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
905 CONFIG_CMD_SHA1SUM * print sha1 memory digest
906 (requires CONFIG_CMD_MEMORY)
907 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
908 CONFIG_CMD_SOURCE "source" command Support
909 CONFIG_CMD_SPI * SPI serial bus support
910 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
911 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
912 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
913 CONFIG_CMD_TIMER * access to the system tick timer
914 CONFIG_CMD_USB * USB support
915 CONFIG_CMD_CDP * Cisco Discover Protocol support
916 CONFIG_CMD_MFSL * Microblaze FSL support
917 CONFIG_CMD_XIMG Load part of Multi Image
920 EXAMPLE: If you want all functions except of network
921 support you can write:
923 #include "config_cmd_all.h"
924 #undef CONFIG_CMD_NET
927 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
929 Note: Don't enable the "icache" and "dcache" commands
930 (configuration option CONFIG_CMD_CACHE) unless you know
931 what you (and your U-Boot users) are doing. Data
932 cache cannot be enabled on systems like the 8xx or
933 8260 (where accesses to the IMMR region must be
934 uncached), and it cannot be disabled on all other
935 systems where we (mis-) use the data cache to hold an
936 initial stack and some data.
939 XXX - this list needs to get updated!
941 - Regular expression support:
943 If this variable is defined, U-Boot is linked against
944 the SLRE (Super Light Regular Expression) library,
945 which adds regex support to some commands, as for
946 example "env grep" and "setexpr".
950 If this variable is defined, U-Boot will use a device tree
951 to configure its devices, instead of relying on statically
952 compiled #defines in the board file. This option is
953 experimental and only available on a few boards. The device
954 tree is available in the global data as gd->fdt_blob.
956 U-Boot needs to get its device tree from somewhere. This can
957 be done using one of the two options below:
960 If this variable is defined, U-Boot will embed a device tree
961 binary in its image. This device tree file should be in the
962 board directory and called <soc>-<board>.dts. The binary file
963 is then picked up in board_init_f() and made available through
964 the global data structure as gd->blob.
967 If this variable is defined, U-Boot will build a device tree
968 binary. It will be called u-boot.dtb. Architecture-specific
969 code will locate it at run-time. Generally this works by:
971 cat u-boot.bin u-boot.dtb >image.bin
973 and in fact, U-Boot does this for you, creating a file called
974 u-boot-dtb.bin which is useful in the common case. You can
975 still use the individual files if you need something more
980 If this variable is defined, it enables watchdog
981 support for the SoC. There must be support in the SoC
982 specific code for a watchdog. For the 8xx and 8260
983 CPUs, the SIU Watchdog feature is enabled in the SYPCR
984 register. When supported for a specific SoC is
985 available, then no further board specific code should
989 When using a watchdog circuitry external to the used
990 SoC, then define this variable and provide board
991 specific code for the "hw_watchdog_reset" function.
994 CONFIG_VERSION_VARIABLE
995 If this variable is defined, an environment variable
996 named "ver" is created by U-Boot showing the U-Boot
997 version as printed by the "version" command.
998 Any change to this variable will be reverted at the
1003 When CONFIG_CMD_DATE is selected, the type of the RTC
1004 has to be selected, too. Define exactly one of the
1007 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1008 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1009 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1010 CONFIG_RTC_MC146818 - use MC146818 RTC
1011 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1012 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1013 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1014 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1015 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1016 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1017 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1018 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1021 Note that if the RTC uses I2C, then the I2C interface
1022 must also be configured. See I2C Support, below.
1025 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1026 CONFIG_PCA953X_INFO - enable pca953x info command
1028 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1029 chip-ngpio pairs that tell the PCA953X driver the number of
1030 pins supported by a particular chip.
1032 Note that if the GPIO device uses I2C, then the I2C interface
1033 must also be configured. See I2C Support, below.
1035 - Timestamp Support:
1037 When CONFIG_TIMESTAMP is selected, the timestamp
1038 (date and time) of an image is printed by image
1039 commands like bootm or iminfo. This option is
1040 automatically enabled when you select CONFIG_CMD_DATE .
1042 - Partition Labels (disklabels) Supported:
1043 Zero or more of the following:
1044 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1045 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1046 Intel architecture, USB sticks, etc.
1047 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1048 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1049 bootloader. Note 2TB partition limit; see
1051 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1053 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1054 CONFIG_CMD_SCSI) you must configure support for at
1055 least one non-MTD partition type as well.
1058 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1059 board configurations files but used nowhere!
1061 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1062 be performed by calling the function
1063 ide_set_reset(int reset)
1064 which has to be defined in a board specific file
1069 Set this to enable ATAPI support.
1074 Set this to enable support for disks larger than 137GB
1075 Also look at CONFIG_SYS_64BIT_LBA.
1076 Whithout these , LBA48 support uses 32bit variables and will 'only'
1077 support disks up to 2.1TB.
1079 CONFIG_SYS_64BIT_LBA:
1080 When enabled, makes the IDE subsystem use 64bit sector addresses.
1084 At the moment only there is only support for the
1085 SYM53C8XX SCSI controller; define
1086 CONFIG_SCSI_SYM53C8XX to enable it.
1088 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1089 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1090 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1091 maximum numbers of LUNs, SCSI ID's and target
1093 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1095 The environment variable 'scsidevs' is set to the number of
1096 SCSI devices found during the last scan.
1098 - NETWORK Support (PCI):
1100 Support for Intel 8254x/8257x gigabit chips.
1103 Utility code for direct access to the SPI bus on Intel 8257x.
1104 This does not do anything useful unless you set at least one
1105 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1107 CONFIG_E1000_SPI_GENERIC
1108 Allow generic access to the SPI bus on the Intel 8257x, for
1109 example with the "sspi" command.
1112 Management command for E1000 devices. When used on devices
1113 with SPI support you can reprogram the EEPROM from U-Boot.
1115 CONFIG_E1000_FALLBACK_MAC
1116 default MAC for empty EEPROM after production.
1119 Support for Intel 82557/82559/82559ER chips.
1120 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1121 write routine for first time initialisation.
1124 Support for Digital 2114x chips.
1125 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1126 modem chip initialisation (KS8761/QS6611).
1129 Support for National dp83815 chips.
1132 Support for National dp8382[01] gigabit chips.
1134 - NETWORK Support (other):
1136 CONFIG_DRIVER_AT91EMAC
1137 Support for AT91RM9200 EMAC.
1140 Define this to use reduced MII inteface
1142 CONFIG_DRIVER_AT91EMAC_QUIET
1143 If this defined, the driver is quiet.
1144 The driver doen't show link status messages.
1146 CONFIG_CALXEDA_XGMAC
1147 Support for the Calxeda XGMAC device
1150 Support for SMSC's LAN91C96 chips.
1152 CONFIG_LAN91C96_BASE
1153 Define this to hold the physical address
1154 of the LAN91C96's I/O space
1156 CONFIG_LAN91C96_USE_32_BIT
1157 Define this to enable 32 bit addressing
1160 Support for SMSC's LAN91C111 chip
1162 CONFIG_SMC91111_BASE
1163 Define this to hold the physical address
1164 of the device (I/O space)
1166 CONFIG_SMC_USE_32_BIT
1167 Define this if data bus is 32 bits
1169 CONFIG_SMC_USE_IOFUNCS
1170 Define this to use i/o functions instead of macros
1171 (some hardware wont work with macros)
1173 CONFIG_DRIVER_TI_EMAC
1174 Support for davinci emac
1176 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1177 Define this if you have more then 3 PHYs.
1180 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1182 CONFIG_FTGMAC100_EGIGA
1183 Define this to use GE link update with gigabit PHY.
1184 Define this if FTGMAC100 is connected to gigabit PHY.
1185 If your system has 10/100 PHY only, it might not occur
1186 wrong behavior. Because PHY usually return timeout or
1187 useless data when polling gigabit status and gigabit
1188 control registers. This behavior won't affect the
1189 correctnessof 10/100 link speed update.
1192 Support for SMSC's LAN911x and LAN921x chips
1195 Define this to hold the physical address
1196 of the device (I/O space)
1198 CONFIG_SMC911X_32_BIT
1199 Define this if data bus is 32 bits
1201 CONFIG_SMC911X_16_BIT
1202 Define this if data bus is 16 bits. If your processor
1203 automatically converts one 32 bit word to two 16 bit
1204 words you may also try CONFIG_SMC911X_32_BIT.
1207 Support for Renesas on-chip Ethernet controller
1209 CONFIG_SH_ETHER_USE_PORT
1210 Define the number of ports to be used
1212 CONFIG_SH_ETHER_PHY_ADDR
1213 Define the ETH PHY's address
1215 CONFIG_SH_ETHER_CACHE_WRITEBACK
1216 If this option is set, the driver enables cache flush.
1220 Support TPM devices.
1223 Support for i2c bus TPM devices. Only one device
1224 per system is supported at this time.
1226 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1227 Define the the i2c bus number for the TPM device
1229 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1230 Define the TPM's address on the i2c bus
1232 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1233 Define the burst count bytes upper limit
1235 CONFIG_TPM_ATMEL_TWI
1236 Support for Atmel TWI TPM device. Requires I2C support.
1239 Support for generic parallel port TPM devices. Only one device
1240 per system is supported at this time.
1242 CONFIG_TPM_TIS_BASE_ADDRESS
1243 Base address where the generic TPM device is mapped
1244 to. Contemporary x86 systems usually map it at
1248 Add tpm monitor functions.
1249 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1250 provides monitor access to authorized functions.
1253 Define this to enable the TPM support library which provides
1254 functional interfaces to some TPM commands.
1255 Requires support for a TPM device.
1257 CONFIG_TPM_AUTH_SESSIONS
1258 Define this to enable authorized functions in the TPM library.
1259 Requires CONFIG_TPM and CONFIG_SHA1.
1262 At the moment only the UHCI host controller is
1263 supported (PIP405, MIP405, MPC5200); define
1264 CONFIG_USB_UHCI to enable it.
1265 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1266 and define CONFIG_USB_STORAGE to enable the USB
1269 Supported are USB Keyboards and USB Floppy drives
1271 MPC5200 USB requires additional defines:
1273 for 528 MHz Clock: 0x0001bbbb
1277 for differential drivers: 0x00001000
1278 for single ended drivers: 0x00005000
1279 for differential drivers on PSC3: 0x00000100
1280 for single ended drivers on PSC3: 0x00004100
1281 CONFIG_SYS_USB_EVENT_POLL
1282 May be defined to allow interrupt polling
1283 instead of using asynchronous interrupts
1285 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1286 txfilltuning field in the EHCI controller on reset.
1288 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1289 interval for usb hub power-on delay.(minimum 100msec)
1292 Define the below if you wish to use the USB console.
1293 Once firmware is rebuilt from a serial console issue the
1294 command "setenv stdin usbtty; setenv stdout usbtty" and
1295 attach your USB cable. The Unix command "dmesg" should print
1296 it has found a new device. The environment variable usbtty
1297 can be set to gserial or cdc_acm to enable your device to
1298 appear to a USB host as a Linux gserial device or a
1299 Common Device Class Abstract Control Model serial device.
1300 If you select usbtty = gserial you should be able to enumerate
1302 # modprobe usbserial vendor=0xVendorID product=0xProductID
1303 else if using cdc_acm, simply setting the environment
1304 variable usbtty to be cdc_acm should suffice. The following
1305 might be defined in YourBoardName.h
1308 Define this to build a UDC device
1311 Define this to have a tty type of device available to
1312 talk to the UDC device
1315 Define this to enable the high speed support for usb
1316 device and usbtty. If this feature is enabled, a routine
1317 int is_usbd_high_speed(void)
1318 also needs to be defined by the driver to dynamically poll
1319 whether the enumeration has succeded at high speed or full
1322 CONFIG_SYS_CONSOLE_IS_IN_ENV
1323 Define this if you want stdin, stdout &/or stderr to
1327 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1328 Derive USB clock from external clock "blah"
1329 - CONFIG_SYS_USB_EXTC_CLK 0x02
1331 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1332 Derive USB clock from brgclk
1333 - CONFIG_SYS_USB_BRG_CLK 0x04
1335 If you have a USB-IF assigned VendorID then you may wish to
1336 define your own vendor specific values either in BoardName.h
1337 or directly in usbd_vendor_info.h. If you don't define
1338 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1339 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1340 should pretend to be a Linux device to it's target host.
1342 CONFIG_USBD_MANUFACTURER
1343 Define this string as the name of your company for
1344 - CONFIG_USBD_MANUFACTURER "my company"
1346 CONFIG_USBD_PRODUCT_NAME
1347 Define this string as the name of your product
1348 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1350 CONFIG_USBD_VENDORID
1351 Define this as your assigned Vendor ID from the USB
1352 Implementors Forum. This *must* be a genuine Vendor ID
1353 to avoid polluting the USB namespace.
1354 - CONFIG_USBD_VENDORID 0xFFFF
1356 CONFIG_USBD_PRODUCTID
1357 Define this as the unique Product ID
1359 - CONFIG_USBD_PRODUCTID 0xFFFF
1361 - ULPI Layer Support:
1362 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1363 the generic ULPI layer. The generic layer accesses the ULPI PHY
1364 via the platform viewport, so you need both the genric layer and
1365 the viewport enabled. Currently only Chipidea/ARC based
1366 viewport is supported.
1367 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1368 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1369 If your ULPI phy needs a different reference clock than the
1370 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1371 the appropriate value in Hz.
1374 The MMC controller on the Intel PXA is supported. To
1375 enable this define CONFIG_MMC. The MMC can be
1376 accessed from the boot prompt by mapping the device
1377 to physical memory similar to flash. Command line is
1378 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1379 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1382 Support for Renesas on-chip MMCIF controller
1384 CONFIG_SH_MMCIF_ADDR
1385 Define the base address of MMCIF registers
1388 Define the clock frequency for MMCIF
1390 - USB Device Firmware Update (DFU) class support:
1392 This enables the USB portion of the DFU USB class
1395 This enables the command "dfu" which is used to have
1396 U-Boot create a DFU class device via USB. This command
1397 requires that the "dfu_alt_info" environment variable be
1398 set and define the alt settings to expose to the host.
1401 This enables support for exposing (e)MMC devices via DFU.
1404 This enables support for exposing NAND devices via DFU.
1406 CONFIG_SYS_DFU_DATA_BUF_SIZE
1407 Dfu transfer uses a buffer before writing data to the
1408 raw storage device. Make the size (in bytes) of this buffer
1409 configurable. The size of this buffer is also configurable
1410 through the "dfu_bufsiz" environment variable.
1412 CONFIG_SYS_DFU_MAX_FILE_SIZE
1413 When updating files rather than the raw storage device,
1414 we use a static buffer to copy the file into and then write
1415 the buffer once we've been given the whole file. Define
1416 this to the maximum filesize (in bytes) for the buffer.
1417 Default is 4 MiB if undefined.
1419 - Journaling Flash filesystem support:
1420 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1421 CONFIG_JFFS2_NAND_DEV
1422 Define these for a default partition on a NAND device
1424 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1425 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1426 Define these for a default partition on a NOR device
1428 CONFIG_SYS_JFFS_CUSTOM_PART
1429 Define this to create an own partition. You have to provide a
1430 function struct part_info* jffs2_part_info(int part_num)
1432 If you define only one JFFS2 partition you may also want to
1433 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1434 to disable the command chpart. This is the default when you
1435 have not defined a custom partition
1437 - FAT(File Allocation Table) filesystem write function support:
1440 Define this to enable support for saving memory data as a
1441 file in FAT formatted partition.
1443 This will also enable the command "fatwrite" enabling the
1444 user to write files to FAT.
1446 CBFS (Coreboot Filesystem) support
1449 Define this to enable support for reading from a Coreboot
1450 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1456 Define this to enable standard (PC-Style) keyboard
1460 Standard PC keyboard driver with US (is default) and
1461 GERMAN key layout (switch via environment 'keymap=de') support.
1462 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1463 for cfb_console. Supports cursor blinking.
1466 Enables a Chrome OS keyboard using the CROS_EC interface.
1467 This uses CROS_EC to communicate with a second microcontroller
1468 which provides key scans on request.
1473 Define this to enable video support (for output to
1476 CONFIG_VIDEO_CT69000
1478 Enable Chips & Technologies 69000 Video chip
1480 CONFIG_VIDEO_SMI_LYNXEM
1481 Enable Silicon Motion SMI 712/710/810 Video chip. The
1482 video output is selected via environment 'videoout'
1483 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1486 For the CT69000 and SMI_LYNXEM drivers, videomode is
1487 selected via environment 'videomode'. Two different ways
1489 - "videomode=num" 'num' is a standard LiLo mode numbers.
1490 Following standard modes are supported (* is default):
1492 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1493 -------------+---------------------------------------------
1494 8 bits | 0x301* 0x303 0x305 0x161 0x307
1495 15 bits | 0x310 0x313 0x316 0x162 0x319
1496 16 bits | 0x311 0x314 0x317 0x163 0x31A
1497 24 bits | 0x312 0x315 0x318 ? 0x31B
1498 -------------+---------------------------------------------
1499 (i.e. setenv videomode 317; saveenv; reset;)
1501 - "videomode=bootargs" all the video parameters are parsed
1502 from the bootargs. (See drivers/video/videomodes.c)
1505 CONFIG_VIDEO_SED13806
1506 Enable Epson SED13806 driver. This driver supports 8bpp
1507 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1508 or CONFIG_VIDEO_SED13806_16BPP
1511 Enable the Freescale DIU video driver. Reference boards for
1512 SOCs that have a DIU should define this macro to enable DIU
1513 support, and should also define these other macros:
1519 CONFIG_VIDEO_SW_CURSOR
1520 CONFIG_VGA_AS_SINGLE_DEVICE
1522 CONFIG_VIDEO_BMP_LOGO
1524 The DIU driver will look for the 'video-mode' environment
1525 variable, and if defined, enable the DIU as a console during
1526 boot. See the documentation file README.video for a
1527 description of this variable.
1531 Enable the VGA video / BIOS for x86. The alternative if you
1532 are using coreboot is to use the coreboot frame buffer
1539 Define this to enable a custom keyboard support.
1540 This simply calls drv_keyboard_init() which must be
1541 defined in your board-specific files.
1542 The only board using this so far is RBC823.
1544 - LCD Support: CONFIG_LCD
1546 Define this to enable LCD support (for output to LCD
1547 display); also select one of the supported displays
1548 by defining one of these:
1552 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1554 CONFIG_NEC_NL6448AC33:
1556 NEC NL6448AC33-18. Active, color, single scan.
1558 CONFIG_NEC_NL6448BC20
1560 NEC NL6448BC20-08. 6.5", 640x480.
1561 Active, color, single scan.
1563 CONFIG_NEC_NL6448BC33_54
1565 NEC NL6448BC33-54. 10.4", 640x480.
1566 Active, color, single scan.
1570 Sharp 320x240. Active, color, single scan.
1571 It isn't 16x9, and I am not sure what it is.
1573 CONFIG_SHARP_LQ64D341
1575 Sharp LQ64D341 display, 640x480.
1576 Active, color, single scan.
1580 HLD1045 display, 640x480.
1581 Active, color, single scan.
1585 Optrex CBL50840-2 NF-FW 99 22 M5
1587 Hitachi LMG6912RPFC-00T
1591 320x240. Black & white.
1593 Normally display is black on white background; define
1594 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1596 CONFIG_LCD_ALIGNMENT
1598 Normally the LCD is page-aligned (tyically 4KB). If this is
1599 defined then the LCD will be aligned to this value instead.
1600 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1601 here, since it is cheaper to change data cache settings on
1602 a per-section basis.
1604 CONFIG_CONSOLE_SCROLL_LINES
1606 When the console need to be scrolled, this is the number of
1607 lines to scroll by. It defaults to 1. Increasing this makes
1608 the console jump but can help speed up operation when scrolling
1613 Support drawing of RLE8-compressed bitmaps on the LCD.
1617 Enables an 'i2c edid' command which can read EDID
1618 information over I2C from an attached LCD display.
1620 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1622 If this option is set, the environment is checked for
1623 a variable "splashimage". If found, the usual display
1624 of logo, copyright and system information on the LCD
1625 is suppressed and the BMP image at the address
1626 specified in "splashimage" is loaded instead. The
1627 console is redirected to the "nulldev", too. This
1628 allows for a "silent" boot where a splash screen is
1629 loaded very quickly after power-on.
1631 CONFIG_SPLASHIMAGE_GUARD
1633 If this option is set, then U-Boot will prevent the environment
1634 variable "splashimage" from being set to a problematic address
1635 (see README.displaying-bmps and README.arm-unaligned-accesses).
1636 This option is useful for targets where, due to alignment
1637 restrictions, an improperly aligned BMP image will cause a data
1638 abort. If you think you will not have problems with unaligned
1639 accesses (for example because your toolchain prevents them)
1640 there is no need to set this option.
1642 CONFIG_SPLASH_SCREEN_ALIGN
1644 If this option is set the splash image can be freely positioned
1645 on the screen. Environment variable "splashpos" specifies the
1646 position as "x,y". If a positive number is given it is used as
1647 number of pixel from left/top. If a negative number is given it
1648 is used as number of pixel from right/bottom. You can also
1649 specify 'm' for centering the image.
1652 setenv splashpos m,m
1653 => image at center of screen
1655 setenv splashpos 30,20
1656 => image at x = 30 and y = 20
1658 setenv splashpos -10,m
1659 => vertically centered image
1660 at x = dspWidth - bmpWidth - 9
1662 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1664 If this option is set, additionally to standard BMP
1665 images, gzipped BMP images can be displayed via the
1666 splashscreen support or the bmp command.
1668 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1670 If this option is set, 8-bit RLE compressed BMP images
1671 can be displayed via the splashscreen support or the
1674 - Do compresssing for memory range:
1677 If this option is set, it would use zlib deflate method
1678 to compress the specified memory at its best effort.
1680 - Compression support:
1683 Enabled by default to support gzip compressed images.
1687 If this option is set, support for bzip2 compressed
1688 images is included. If not, only uncompressed and gzip
1689 compressed images are supported.
1691 NOTE: the bzip2 algorithm requires a lot of RAM, so
1692 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1697 If this option is set, support for lzma compressed
1700 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1701 requires an amount of dynamic memory that is given by the
1704 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1706 Where lc and lp stand for, respectively, Literal context bits
1707 and Literal pos bits.
1709 This value is upper-bounded by 14MB in the worst case. Anyway,
1710 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1711 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1712 a very small buffer.
1714 Use the lzmainfo tool to determinate the lc and lp values and
1715 then calculate the amount of needed dynamic memory (ensuring
1716 the appropriate CONFIG_SYS_MALLOC_LEN value).
1720 If this option is set, support for LZO compressed images
1726 The address of PHY on MII bus.
1728 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1730 The clock frequency of the MII bus
1734 If this option is set, support for speed/duplex
1735 detection of gigabit PHY is included.
1737 CONFIG_PHY_RESET_DELAY
1739 Some PHY like Intel LXT971A need extra delay after
1740 reset before any MII register access is possible.
1741 For such PHY, set this option to the usec delay
1742 required. (minimum 300usec for LXT971A)
1744 CONFIG_PHY_CMD_DELAY (ppc4xx)
1746 Some PHY like Intel LXT971A need extra delay after
1747 command issued before MII status register can be read
1757 Define a default value for Ethernet address to use
1758 for the respective Ethernet interface, in case this
1759 is not determined automatically.
1764 Define a default value for the IP address to use for
1765 the default Ethernet interface, in case this is not
1766 determined through e.g. bootp.
1767 (Environment variable "ipaddr")
1769 - Server IP address:
1772 Defines a default value for the IP address of a TFTP
1773 server to contact when using the "tftboot" command.
1774 (Environment variable "serverip")
1776 CONFIG_KEEP_SERVERADDR
1778 Keeps the server's MAC address, in the env 'serveraddr'
1779 for passing to bootargs (like Linux's netconsole option)
1781 - Gateway IP address:
1784 Defines a default value for the IP address of the
1785 default router where packets to other networks are
1787 (Environment variable "gatewayip")
1792 Defines a default value for the subnet mask (or
1793 routing prefix) which is used to determine if an IP
1794 address belongs to the local subnet or needs to be
1795 forwarded through a router.
1796 (Environment variable "netmask")
1798 - Multicast TFTP Mode:
1801 Defines whether you want to support multicast TFTP as per
1802 rfc-2090; for example to work with atftp. Lets lots of targets
1803 tftp down the same boot image concurrently. Note: the Ethernet
1804 driver in use must provide a function: mcast() to join/leave a
1807 - BOOTP Recovery Mode:
1808 CONFIG_BOOTP_RANDOM_DELAY
1810 If you have many targets in a network that try to
1811 boot using BOOTP, you may want to avoid that all
1812 systems send out BOOTP requests at precisely the same
1813 moment (which would happen for instance at recovery
1814 from a power failure, when all systems will try to
1815 boot, thus flooding the BOOTP server. Defining
1816 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1817 inserted before sending out BOOTP requests. The
1818 following delays are inserted then:
1820 1st BOOTP request: delay 0 ... 1 sec
1821 2nd BOOTP request: delay 0 ... 2 sec
1822 3rd BOOTP request: delay 0 ... 4 sec
1824 BOOTP requests: delay 0 ... 8 sec
1826 - DHCP Advanced Options:
1827 You can fine tune the DHCP functionality by defining
1828 CONFIG_BOOTP_* symbols:
1830 CONFIG_BOOTP_SUBNETMASK
1831 CONFIG_BOOTP_GATEWAY
1832 CONFIG_BOOTP_HOSTNAME
1833 CONFIG_BOOTP_NISDOMAIN
1834 CONFIG_BOOTP_BOOTPATH
1835 CONFIG_BOOTP_BOOTFILESIZE
1838 CONFIG_BOOTP_SEND_HOSTNAME
1839 CONFIG_BOOTP_NTPSERVER
1840 CONFIG_BOOTP_TIMEOFFSET
1841 CONFIG_BOOTP_VENDOREX
1842 CONFIG_BOOTP_MAY_FAIL
1844 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1845 environment variable, not the BOOTP server.
1847 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1848 after the configured retry count, the call will fail
1849 instead of starting over. This can be used to fail over
1850 to Link-local IP address configuration if the DHCP server
1853 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1854 serverip from a DHCP server, it is possible that more
1855 than one DNS serverip is offered to the client.
1856 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1857 serverip will be stored in the additional environment
1858 variable "dnsip2". The first DNS serverip is always
1859 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1862 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1863 to do a dynamic update of a DNS server. To do this, they
1864 need the hostname of the DHCP requester.
1865 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1866 of the "hostname" environment variable is passed as
1867 option 12 to the DHCP server.
1869 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1871 A 32bit value in microseconds for a delay between
1872 receiving a "DHCP Offer" and sending the "DHCP Request".
1873 This fixes a problem with certain DHCP servers that don't
1874 respond 100% of the time to a "DHCP request". E.g. On an
1875 AT91RM9200 processor running at 180MHz, this delay needed
1876 to be *at least* 15,000 usec before a Windows Server 2003
1877 DHCP server would reply 100% of the time. I recommend at
1878 least 50,000 usec to be safe. The alternative is to hope
1879 that one of the retries will be successful but note that
1880 the DHCP timeout and retry process takes a longer than
1883 - Link-local IP address negotiation:
1884 Negotiate with other link-local clients on the local network
1885 for an address that doesn't require explicit configuration.
1886 This is especially useful if a DHCP server cannot be guaranteed
1887 to exist in all environments that the device must operate.
1889 See doc/README.link-local for more information.
1892 CONFIG_CDP_DEVICE_ID
1894 The device id used in CDP trigger frames.
1896 CONFIG_CDP_DEVICE_ID_PREFIX
1898 A two character string which is prefixed to the MAC address
1903 A printf format string which contains the ascii name of
1904 the port. Normally is set to "eth%d" which sets
1905 eth0 for the first Ethernet, eth1 for the second etc.
1907 CONFIG_CDP_CAPABILITIES
1909 A 32bit integer which indicates the device capabilities;
1910 0x00000010 for a normal host which does not forwards.
1914 An ascii string containing the version of the software.
1918 An ascii string containing the name of the platform.
1922 A 32bit integer sent on the trigger.
1924 CONFIG_CDP_POWER_CONSUMPTION
1926 A 16bit integer containing the power consumption of the
1927 device in .1 of milliwatts.
1929 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1931 A byte containing the id of the VLAN.
1933 - Status LED: CONFIG_STATUS_LED
1935 Several configurations allow to display the current
1936 status using a LED. For instance, the LED will blink
1937 fast while running U-Boot code, stop blinking as
1938 soon as a reply to a BOOTP request was received, and
1939 start blinking slow once the Linux kernel is running
1940 (supported by a status LED driver in the Linux
1941 kernel). Defining CONFIG_STATUS_LED enables this
1944 - CAN Support: CONFIG_CAN_DRIVER
1946 Defining CONFIG_CAN_DRIVER enables CAN driver support
1947 on those systems that support this (optional)
1948 feature, like the TQM8xxL modules.
1950 - I2C Support: CONFIG_SYS_I2C
1952 This enable the NEW i2c subsystem, and will allow you to use
1953 i2c commands at the u-boot command line (as long as you set
1954 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1955 based realtime clock chips or other i2c devices. See
1956 common/cmd_i2c.c for a description of the command line
1959 ported i2c driver to the new framework:
1960 - drivers/i2c/soft_i2c.c:
1961 - activate first bus with CONFIG_SYS_I2C_SOFT define
1962 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1963 for defining speed and slave address
1964 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1965 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1966 for defining speed and slave address
1967 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1968 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1969 for defining speed and slave address
1970 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1971 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1972 for defining speed and slave address
1974 - drivers/i2c/fsl_i2c.c:
1975 - activate i2c driver with CONFIG_SYS_I2C_FSL
1976 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1977 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1978 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1980 - If your board supports a second fsl i2c bus, define
1981 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1982 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1983 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1986 - drivers/i2c/tegra_i2c.c:
1987 - activate this driver with CONFIG_SYS_I2C_TEGRA
1988 - This driver adds 4 i2c buses with a fix speed from
1989 100000 and the slave addr 0!
1991 - drivers/i2c/ppc4xx_i2c.c
1992 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1993 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1994 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1998 CONFIG_SYS_NUM_I2C_BUSES
1999 Hold the number of i2c busses you want to use. If you
2000 don't use/have i2c muxes on your i2c bus, this
2001 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can
2004 CONFIG_SYS_I2C_DIRECT_BUS
2005 define this, if you don't use i2c muxes on your hardware.
2006 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
2009 CONFIG_SYS_I2C_MAX_HOPS
2010 define how many muxes are maximal consecutively connected
2011 on one i2c bus. If you not use i2c muxes, omit this
2014 CONFIG_SYS_I2C_BUSES
2015 hold a list of busses you want to use, only used if
2016 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
2017 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
2018 CONFIG_SYS_NUM_I2C_BUSES = 9:
2020 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
2021 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
2022 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
2023 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
2024 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
2025 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
2026 {1, {I2C_NULL_HOP}}, \
2027 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
2028 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
2032 bus 0 on adapter 0 without a mux
2033 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
2034 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
2035 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
2036 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
2037 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
2038 bus 6 on adapter 1 without a mux
2039 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
2040 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
2042 If you do not have i2c muxes on your board, omit this define.
2044 - Legacy I2C Support: CONFIG_HARD_I2C
2046 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which
2047 provides the following compelling advantages:
2049 - more than one i2c adapter is usable
2050 - approved multibus support
2051 - better i2c mux support
2053 ** Please consider updating your I2C driver now. **
2055 These enable legacy I2C serial bus commands. Defining
2056 CONFIG_HARD_I2C will include the appropriate I2C driver
2057 for the selected CPU.
2059 This will allow you to use i2c commands at the u-boot
2060 command line (as long as you set CONFIG_CMD_I2C in
2061 CONFIG_COMMANDS) and communicate with i2c based realtime
2062 clock chips. See common/cmd_i2c.c for a description of the
2063 command line interface.
2065 CONFIG_HARD_I2C selects a hardware I2C controller.
2067 There are several other quantities that must also be
2068 defined when you define CONFIG_HARD_I2C.
2070 In both cases you will need to define CONFIG_SYS_I2C_SPEED
2071 to be the frequency (in Hz) at which you wish your i2c bus
2072 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
2073 the CPU's i2c node address).
2075 Now, the u-boot i2c code for the mpc8xx
2076 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
2077 and so its address should therefore be cleared to 0 (See,
2078 eg, MPC823e User's Manual p.16-473). So, set
2079 CONFIG_SYS_I2C_SLAVE to 0.
2081 CONFIG_SYS_I2C_INIT_MPC5XXX
2083 When a board is reset during an i2c bus transfer
2084 chips might think that the current transfer is still
2085 in progress. Reset the slave devices by sending start
2086 commands until the slave device responds.
2088 That's all that's required for CONFIG_HARD_I2C.
2090 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
2091 then the following macros need to be defined (examples are
2092 from include/configs/lwmon.h):
2096 (Optional). Any commands necessary to enable the I2C
2097 controller or configure ports.
2099 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
2103 (Only for MPC8260 CPU). The I/O port to use (the code
2104 assumes both bits are on the same port). Valid values
2105 are 0..3 for ports A..D.
2109 The code necessary to make the I2C data line active
2110 (driven). If the data line is open collector, this
2113 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2117 The code necessary to make the I2C data line tri-stated
2118 (inactive). If the data line is open collector, this
2121 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2125 Code that returns true if the I2C data line is high,
2128 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2132 If <bit> is true, sets the I2C data line high. If it
2133 is false, it clears it (low).
2135 eg: #define I2C_SDA(bit) \
2136 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2137 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2141 If <bit> is true, sets the I2C clock line high. If it
2142 is false, it clears it (low).
2144 eg: #define I2C_SCL(bit) \
2145 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2146 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2150 This delay is invoked four times per clock cycle so this
2151 controls the rate of data transfer. The data rate thus
2152 is 1 / (I2C_DELAY * 4). Often defined to be something
2155 #define I2C_DELAY udelay(2)
2157 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2159 If your arch supports the generic GPIO framework (asm/gpio.h),
2160 then you may alternatively define the two GPIOs that are to be
2161 used as SCL / SDA. Any of the previous I2C_xxx macros will
2162 have GPIO-based defaults assigned to them as appropriate.
2164 You should define these to the GPIO value as given directly to
2165 the generic GPIO functions.
2167 CONFIG_SYS_I2C_INIT_BOARD
2169 When a board is reset during an i2c bus transfer
2170 chips might think that the current transfer is still
2171 in progress. On some boards it is possible to access
2172 the i2c SCLK line directly, either by using the
2173 processor pin as a GPIO or by having a second pin
2174 connected to the bus. If this option is defined a
2175 custom i2c_init_board() routine in boards/xxx/board.c
2176 is run early in the boot sequence.
2178 CONFIG_SYS_I2C_BOARD_LATE_INIT
2180 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2181 defined a custom i2c_board_late_init() routine in
2182 boards/xxx/board.c is run AFTER the operations in i2c_init()
2183 is completed. This callpoint can be used to unreset i2c bus
2184 using CPU i2c controller register accesses for CPUs whose i2c
2185 controller provide such a method. It is called at the end of
2186 i2c_init() to allow i2c_init operations to setup the i2c bus
2187 controller on the CPU (e.g. setting bus speed & slave address).
2189 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2191 This option enables configuration of bi_iic_fast[] flags
2192 in u-boot bd_info structure based on u-boot environment
2193 variable "i2cfast". (see also i2cfast)
2195 CONFIG_I2C_MULTI_BUS
2197 This option allows the use of multiple I2C buses, each of which
2198 must have a controller. At any point in time, only one bus is
2199 active. To switch to a different bus, use the 'i2c dev' command.
2200 Note that bus numbering is zero-based.
2202 CONFIG_SYS_I2C_NOPROBES
2204 This option specifies a list of I2C devices that will be skipped
2205 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2206 is set, specify a list of bus-device pairs. Otherwise, specify
2207 a 1D array of device addresses
2210 #undef CONFIG_I2C_MULTI_BUS
2211 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2213 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2215 #define CONFIG_I2C_MULTI_BUS
2216 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2218 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2220 CONFIG_SYS_SPD_BUS_NUM
2222 If defined, then this indicates the I2C bus number for DDR SPD.
2223 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2225 CONFIG_SYS_RTC_BUS_NUM
2227 If defined, then this indicates the I2C bus number for the RTC.
2228 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2230 CONFIG_SYS_DTT_BUS_NUM
2232 If defined, then this indicates the I2C bus number for the DTT.
2233 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2235 CONFIG_SYS_I2C_DTT_ADDR:
2237 If defined, specifies the I2C address of the DTT device.
2238 If not defined, then U-Boot uses predefined value for
2239 specified DTT device.
2241 CONFIG_SOFT_I2C_READ_REPEATED_START
2243 defining this will force the i2c_read() function in
2244 the soft_i2c driver to perform an I2C repeated start
2245 between writing the address pointer and reading the
2246 data. If this define is omitted the default behaviour
2247 of doing a stop-start sequence will be used. Most I2C
2248 devices can use either method, but some require one or
2251 - SPI Support: CONFIG_SPI
2253 Enables SPI driver (so far only tested with
2254 SPI EEPROM, also an instance works with Crystal A/D and
2255 D/As on the SACSng board)
2259 Enables the driver for SPI controller on SuperH. Currently
2260 only SH7757 is supported.
2264 Enables extended (16-bit) SPI EEPROM addressing.
2265 (symmetrical to CONFIG_I2C_X)
2269 Enables a software (bit-bang) SPI driver rather than
2270 using hardware support. This is a general purpose
2271 driver that only requires three general I/O port pins
2272 (two outputs, one input) to function. If this is
2273 defined, the board configuration must define several
2274 SPI configuration items (port pins to use, etc). For
2275 an example, see include/configs/sacsng.h.
2279 Enables a hardware SPI driver for general-purpose reads
2280 and writes. As with CONFIG_SOFT_SPI, the board configuration
2281 must define a list of chip-select function pointers.
2282 Currently supported on some MPC8xxx processors. For an
2283 example, see include/configs/mpc8349emds.h.
2287 Enables the driver for the SPI controllers on i.MX and MXC
2288 SoCs. Currently i.MX31/35/51 are supported.
2290 - FPGA Support: CONFIG_FPGA
2292 Enables FPGA subsystem.
2294 CONFIG_FPGA_<vendor>
2296 Enables support for specific chip vendors.
2299 CONFIG_FPGA_<family>
2301 Enables support for FPGA family.
2302 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2306 Specify the number of FPGA devices to support.
2308 CONFIG_SYS_FPGA_PROG_FEEDBACK
2310 Enable printing of hash marks during FPGA configuration.
2312 CONFIG_SYS_FPGA_CHECK_BUSY
2314 Enable checks on FPGA configuration interface busy
2315 status by the configuration function. This option
2316 will require a board or device specific function to
2321 If defined, a function that provides delays in the FPGA
2322 configuration driver.
2324 CONFIG_SYS_FPGA_CHECK_CTRLC
2325 Allow Control-C to interrupt FPGA configuration
2327 CONFIG_SYS_FPGA_CHECK_ERROR
2329 Check for configuration errors during FPGA bitfile
2330 loading. For example, abort during Virtex II
2331 configuration if the INIT_B line goes low (which
2332 indicated a CRC error).
2334 CONFIG_SYS_FPGA_WAIT_INIT
2336 Maximum time to wait for the INIT_B line to deassert
2337 after PROB_B has been deasserted during a Virtex II
2338 FPGA configuration sequence. The default time is 500
2341 CONFIG_SYS_FPGA_WAIT_BUSY
2343 Maximum time to wait for BUSY to deassert during
2344 Virtex II FPGA configuration. The default is 5 ms.
2346 CONFIG_SYS_FPGA_WAIT_CONFIG
2348 Time to wait after FPGA configuration. The default is
2351 - Configuration Management:
2354 If defined, this string will be added to the U-Boot
2355 version information (U_BOOT_VERSION)
2357 - Vendor Parameter Protection:
2359 U-Boot considers the values of the environment
2360 variables "serial#" (Board Serial Number) and
2361 "ethaddr" (Ethernet Address) to be parameters that
2362 are set once by the board vendor / manufacturer, and
2363 protects these variables from casual modification by
2364 the user. Once set, these variables are read-only,
2365 and write or delete attempts are rejected. You can
2366 change this behaviour:
2368 If CONFIG_ENV_OVERWRITE is #defined in your config
2369 file, the write protection for vendor parameters is
2370 completely disabled. Anybody can change or delete
2373 Alternatively, if you #define _both_ CONFIG_ETHADDR
2374 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2375 Ethernet address is installed in the environment,
2376 which can be changed exactly ONCE by the user. [The
2377 serial# is unaffected by this, i. e. it remains
2380 The same can be accomplished in a more flexible way
2381 for any variable by configuring the type of access
2382 to allow for those variables in the ".flags" variable
2383 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2388 Define this variable to enable the reservation of
2389 "protected RAM", i. e. RAM which is not overwritten
2390 by U-Boot. Define CONFIG_PRAM to hold the number of
2391 kB you want to reserve for pRAM. You can overwrite
2392 this default value by defining an environment
2393 variable "pram" to the number of kB you want to
2394 reserve. Note that the board info structure will
2395 still show the full amount of RAM. If pRAM is
2396 reserved, a new environment variable "mem" will
2397 automatically be defined to hold the amount of
2398 remaining RAM in a form that can be passed as boot
2399 argument to Linux, for instance like that:
2401 setenv bootargs ... mem=\${mem}
2404 This way you can tell Linux not to use this memory,
2405 either, which results in a memory region that will
2406 not be affected by reboots.
2408 *WARNING* If your board configuration uses automatic
2409 detection of the RAM size, you must make sure that
2410 this memory test is non-destructive. So far, the
2411 following board configurations are known to be
2414 IVMS8, IVML24, SPD8xx, TQM8xxL,
2415 HERMES, IP860, RPXlite, LWMON,
2418 - Access to physical memory region (> 4GB)
2419 Some basic support is provided for operations on memory not
2420 normally accessible to U-Boot - e.g. some architectures
2421 support access to more than 4GB of memory on 32-bit
2422 machines using physical address extension or similar.
2423 Define CONFIG_PHYSMEM to access this basic support, which
2424 currently only supports clearing the memory.
2429 Define this variable to stop the system in case of a
2430 fatal error, so that you have to reset it manually.
2431 This is probably NOT a good idea for an embedded
2432 system where you want the system to reboot
2433 automatically as fast as possible, but it may be
2434 useful during development since you can try to debug
2435 the conditions that lead to the situation.
2437 CONFIG_NET_RETRY_COUNT
2439 This variable defines the number of retries for
2440 network operations like ARP, RARP, TFTP, or BOOTP
2441 before giving up the operation. If not defined, a
2442 default value of 5 is used.
2446 Timeout waiting for an ARP reply in milliseconds.
2450 Timeout in milliseconds used in NFS protocol.
2451 If you encounter "ERROR: Cannot umount" in nfs command,
2452 try longer timeout such as
2453 #define CONFIG_NFS_TIMEOUT 10000UL
2455 - Command Interpreter:
2456 CONFIG_AUTO_COMPLETE
2458 Enable auto completion of commands using TAB.
2460 Note that this feature has NOT been implemented yet
2461 for the "hush" shell.
2464 CONFIG_SYS_HUSH_PARSER
2466 Define this variable to enable the "hush" shell (from
2467 Busybox) as command line interpreter, thus enabling
2468 powerful command line syntax like
2469 if...then...else...fi conditionals or `&&' and '||'
2470 constructs ("shell scripts").
2472 If undefined, you get the old, much simpler behaviour
2473 with a somewhat smaller memory footprint.
2476 CONFIG_SYS_PROMPT_HUSH_PS2
2478 This defines the secondary prompt string, which is
2479 printed when the command interpreter needs more input
2480 to complete a command. Usually "> ".
2484 In the current implementation, the local variables
2485 space and global environment variables space are
2486 separated. Local variables are those you define by
2487 simply typing `name=value'. To access a local
2488 variable later on, you have write `$name' or
2489 `${name}'; to execute the contents of a variable
2490 directly type `$name' at the command prompt.
2492 Global environment variables are those you use
2493 setenv/printenv to work with. To run a command stored
2494 in such a variable, you need to use the run command,
2495 and you must not use the '$' sign to access them.
2497 To store commands and special characters in a
2498 variable, please use double quotation marks
2499 surrounding the whole text of the variable, instead
2500 of the backslashes before semicolons and special
2503 - Commandline Editing and History:
2504 CONFIG_CMDLINE_EDITING
2506 Enable editing and History functions for interactive
2507 commandline input operations
2509 - Default Environment:
2510 CONFIG_EXTRA_ENV_SETTINGS
2512 Define this to contain any number of null terminated
2513 strings (variable = value pairs) that will be part of
2514 the default environment compiled into the boot image.
2516 For example, place something like this in your
2517 board's config file:
2519 #define CONFIG_EXTRA_ENV_SETTINGS \
2523 Warning: This method is based on knowledge about the
2524 internal format how the environment is stored by the
2525 U-Boot code. This is NOT an official, exported
2526 interface! Although it is unlikely that this format
2527 will change soon, there is no guarantee either.
2528 You better know what you are doing here.
2530 Note: overly (ab)use of the default environment is
2531 discouraged. Make sure to check other ways to preset
2532 the environment like the "source" command or the
2535 CONFIG_ENV_VARS_UBOOT_CONFIG
2537 Define this in order to add variables describing the
2538 U-Boot build configuration to the default environment.
2539 These will be named arch, cpu, board, vendor, and soc.
2541 Enabling this option will cause the following to be defined:
2549 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2551 Define this in order to add variables describing certain
2552 run-time determined information about the hardware to the
2553 environment. These will be named board_name, board_rev.
2555 CONFIG_DELAY_ENVIRONMENT
2557 Normally the environment is loaded when the board is
2558 intialised so that it is available to U-Boot. This inhibits
2559 that so that the environment is not available until
2560 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2561 this is instead controlled by the value of
2562 /config/load-environment.
2564 - DataFlash Support:
2565 CONFIG_HAS_DATAFLASH
2567 Defining this option enables DataFlash features and
2568 allows to read/write in Dataflash via the standard
2571 - Serial Flash support
2574 Defining this option enables SPI flash commands
2575 'sf probe/read/write/erase/update'.
2577 Usage requires an initial 'probe' to define the serial
2578 flash parameters, followed by read/write/erase/update
2581 The following defaults may be provided by the platform
2582 to handle the common case when only a single serial
2583 flash is present on the system.
2585 CONFIG_SF_DEFAULT_BUS Bus identifier
2586 CONFIG_SF_DEFAULT_CS Chip-select
2587 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2588 CONFIG_SF_DEFAULT_SPEED in Hz
2592 Define this option to include a destructive SPI flash
2595 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2597 Define this option to use the Bank addr/Extended addr
2598 support on SPI flashes which has size > 16Mbytes.
2600 - SystemACE Support:
2603 Adding this option adds support for Xilinx SystemACE
2604 chips attached via some sort of local bus. The address
2605 of the chip must also be defined in the
2606 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2608 #define CONFIG_SYSTEMACE
2609 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2611 When SystemACE support is added, the "ace" device type
2612 becomes available to the fat commands, i.e. fatls.
2614 - TFTP Fixed UDP Port:
2617 If this is defined, the environment variable tftpsrcp
2618 is used to supply the TFTP UDP source port value.
2619 If tftpsrcp isn't defined, the normal pseudo-random port
2620 number generator is used.
2622 Also, the environment variable tftpdstp is used to supply
2623 the TFTP UDP destination port value. If tftpdstp isn't
2624 defined, the normal port 69 is used.
2626 The purpose for tftpsrcp is to allow a TFTP server to
2627 blindly start the TFTP transfer using the pre-configured
2628 target IP address and UDP port. This has the effect of
2629 "punching through" the (Windows XP) firewall, allowing
2630 the remainder of the TFTP transfer to proceed normally.
2631 A better solution is to properly configure the firewall,
2632 but sometimes that is not allowed.
2637 This enables a generic 'hash' command which can produce
2638 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2642 Enable the hash verify command (hash -v). This adds to code
2645 CONFIG_SHA1 - support SHA1 hashing
2646 CONFIG_SHA256 - support SHA256 hashing
2648 Note: There is also a sha1sum command, which should perhaps
2649 be deprecated in favour of 'hash sha1'.
2651 - Freescale i.MX specific commands:
2652 CONFIG_CMD_HDMIDETECT
2653 This enables 'hdmidet' command which returns true if an
2654 HDMI monitor is detected. This command is i.MX 6 specific.
2657 This enables the 'bmode' (bootmode) command for forcing
2658 a boot from specific media.
2660 This is useful for forcing the ROM's usb downloader to
2661 activate upon a watchdog reset which is nice when iterating
2662 on U-Boot. Using the reset button or running bmode normal
2663 will set it back to normal. This command currently
2664 supports i.MX53 and i.MX6.
2669 This enables the RSA algorithm used for FIT image verification
2670 in U-Boot. See doc/uImage/signature for more information.
2672 The signing part is build into mkimage regardless of this
2676 - Show boot progress:
2677 CONFIG_SHOW_BOOT_PROGRESS
2679 Defining this option allows to add some board-
2680 specific code (calling a user-provided function
2681 "show_boot_progress(int)") that enables you to show
2682 the system's boot progress on some display (for
2683 example, some LED's) on your board. At the moment,
2684 the following checkpoints are implemented:
2686 - Detailed boot stage timing
2688 Define this option to get detailed timing of each stage
2689 of the boot process.
2691 CONFIG_BOOTSTAGE_USER_COUNT
2692 This is the number of available user bootstage records.
2693 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2694 a new ID will be allocated from this stash. If you exceed
2695 the limit, recording will stop.
2697 CONFIG_BOOTSTAGE_REPORT
2698 Define this to print a report before boot, similar to this:
2700 Timer summary in microseconds:
2703 3,575,678 3,575,678 board_init_f start
2704 3,575,695 17 arch_cpu_init A9
2705 3,575,777 82 arch_cpu_init done
2706 3,659,598 83,821 board_init_r start
2707 3,910,375 250,777 main_loop
2708 29,916,167 26,005,792 bootm_start
2709 30,361,327 445,160 start_kernel
2711 CONFIG_CMD_BOOTSTAGE
2712 Add a 'bootstage' command which supports printing a report
2713 and un/stashing of bootstage data.
2715 CONFIG_BOOTSTAGE_FDT
2716 Stash the bootstage information in the FDT. A root 'bootstage'
2717 node is created with each bootstage id as a child. Each child
2718 has a 'name' property and either 'mark' containing the
2719 mark time in microsecond, or 'accum' containing the
2720 accumulated time for that bootstage id in microseconds.
2725 name = "board_init_f";
2734 Code in the Linux kernel can find this in /proc/devicetree.
2736 Legacy uImage format:
2739 1 common/cmd_bootm.c before attempting to boot an image
2740 -1 common/cmd_bootm.c Image header has bad magic number
2741 2 common/cmd_bootm.c Image header has correct magic number
2742 -2 common/cmd_bootm.c Image header has bad checksum
2743 3 common/cmd_bootm.c Image header has correct checksum
2744 -3 common/cmd_bootm.c Image data has bad checksum
2745 4 common/cmd_bootm.c Image data has correct checksum
2746 -4 common/cmd_bootm.c Image is for unsupported architecture
2747 5 common/cmd_bootm.c Architecture check OK
2748 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2749 6 common/cmd_bootm.c Image Type check OK
2750 -6 common/cmd_bootm.c gunzip uncompression error
2751 -7 common/cmd_bootm.c Unimplemented compression type
2752 7 common/cmd_bootm.c Uncompression OK
2753 8 common/cmd_bootm.c No uncompress/copy overwrite error
2754 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2756 9 common/image.c Start initial ramdisk verification
2757 -10 common/image.c Ramdisk header has bad magic number
2758 -11 common/image.c Ramdisk header has bad checksum
2759 10 common/image.c Ramdisk header is OK
2760 -12 common/image.c Ramdisk data has bad checksum
2761 11 common/image.c Ramdisk data has correct checksum
2762 12 common/image.c Ramdisk verification complete, start loading
2763 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2764 13 common/image.c Start multifile image verification
2765 14 common/image.c No initial ramdisk, no multifile, continue.
2767 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2769 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2770 -31 post/post.c POST test failed, detected by post_output_backlog()
2771 -32 post/post.c POST test failed, detected by post_run_single()
2773 34 common/cmd_doc.c before loading a Image from a DOC device
2774 -35 common/cmd_doc.c Bad usage of "doc" command
2775 35 common/cmd_doc.c correct usage of "doc" command
2776 -36 common/cmd_doc.c No boot device
2777 36 common/cmd_doc.c correct boot device
2778 -37 common/cmd_doc.c Unknown Chip ID on boot device
2779 37 common/cmd_doc.c correct chip ID found, device available
2780 -38 common/cmd_doc.c Read Error on boot device
2781 38 common/cmd_doc.c reading Image header from DOC device OK
2782 -39 common/cmd_doc.c Image header has bad magic number
2783 39 common/cmd_doc.c Image header has correct magic number
2784 -40 common/cmd_doc.c Error reading Image from DOC device
2785 40 common/cmd_doc.c Image header has correct magic number
2786 41 common/cmd_ide.c before loading a Image from a IDE device
2787 -42 common/cmd_ide.c Bad usage of "ide" command
2788 42 common/cmd_ide.c correct usage of "ide" command
2789 -43 common/cmd_ide.c No boot device
2790 43 common/cmd_ide.c boot device found
2791 -44 common/cmd_ide.c Device not available
2792 44 common/cmd_ide.c Device available
2793 -45 common/cmd_ide.c wrong partition selected
2794 45 common/cmd_ide.c partition selected
2795 -46 common/cmd_ide.c Unknown partition table
2796 46 common/cmd_ide.c valid partition table found
2797 -47 common/cmd_ide.c Invalid partition type
2798 47 common/cmd_ide.c correct partition type
2799 -48 common/cmd_ide.c Error reading Image Header on boot device
2800 48 common/cmd_ide.c reading Image Header from IDE device OK
2801 -49 common/cmd_ide.c Image header has bad magic number
2802 49 common/cmd_ide.c Image header has correct magic number
2803 -50 common/cmd_ide.c Image header has bad checksum
2804 50 common/cmd_ide.c Image header has correct checksum
2805 -51 common/cmd_ide.c Error reading Image from IDE device
2806 51 common/cmd_ide.c reading Image from IDE device OK
2807 52 common/cmd_nand.c before loading a Image from a NAND device
2808 -53 common/cmd_nand.c Bad usage of "nand" command
2809 53 common/cmd_nand.c correct usage of "nand" command
2810 -54 common/cmd_nand.c No boot device
2811 54 common/cmd_nand.c boot device found
2812 -55 common/cmd_nand.c Unknown Chip ID on boot device
2813 55 common/cmd_nand.c correct chip ID found, device available
2814 -56 common/cmd_nand.c Error reading Image Header on boot device
2815 56 common/cmd_nand.c reading Image Header from NAND device OK
2816 -57 common/cmd_nand.c Image header has bad magic number
2817 57 common/cmd_nand.c Image header has correct magic number
2818 -58 common/cmd_nand.c Error reading Image from NAND device
2819 58 common/cmd_nand.c reading Image from NAND device OK
2821 -60 common/env_common.c Environment has a bad CRC, using default
2823 64 net/eth.c starting with Ethernet configuration.
2824 -64 net/eth.c no Ethernet found.
2825 65 net/eth.c Ethernet found.
2827 -80 common/cmd_net.c usage wrong
2828 80 common/cmd_net.c before calling NetLoop()
2829 -81 common/cmd_net.c some error in NetLoop() occurred
2830 81 common/cmd_net.c NetLoop() back without error
2831 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2832 82 common/cmd_net.c trying automatic boot
2833 83 common/cmd_net.c running "source" command
2834 -83 common/cmd_net.c some error in automatic boot or "source" command
2835 84 common/cmd_net.c end without errors
2840 100 common/cmd_bootm.c Kernel FIT Image has correct format
2841 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2842 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2843 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2844 102 common/cmd_bootm.c Kernel unit name specified
2845 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2846 103 common/cmd_bootm.c Found configuration node
2847 104 common/cmd_bootm.c Got kernel subimage node offset
2848 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2849 105 common/cmd_bootm.c Kernel subimage hash verification OK
2850 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2851 106 common/cmd_bootm.c Architecture check OK
2852 -106 common/cmd_bootm.c Kernel subimage has wrong type
2853 107 common/cmd_bootm.c Kernel subimage type OK
2854 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2855 108 common/cmd_bootm.c Got kernel subimage data/size
2856 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2857 -109 common/cmd_bootm.c Can't get kernel subimage type
2858 -110 common/cmd_bootm.c Can't get kernel subimage comp
2859 -111 common/cmd_bootm.c Can't get kernel subimage os
2860 -112 common/cmd_bootm.c Can't get kernel subimage load address
2861 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2863 120 common/image.c Start initial ramdisk verification
2864 -120 common/image.c Ramdisk FIT image has incorrect format
2865 121 common/image.c Ramdisk FIT image has correct format
2866 122 common/image.c No ramdisk subimage unit name, using configuration
2867 -122 common/image.c Can't get configuration for ramdisk subimage
2868 123 common/image.c Ramdisk unit name specified
2869 -124 common/image.c Can't get ramdisk subimage node offset
2870 125 common/image.c Got ramdisk subimage node offset
2871 -125 common/image.c Ramdisk subimage hash verification failed
2872 126 common/image.c Ramdisk subimage hash verification OK
2873 -126 common/image.c Ramdisk subimage for unsupported architecture
2874 127 common/image.c Architecture check OK
2875 -127 common/image.c Can't get ramdisk subimage data/size
2876 128 common/image.c Got ramdisk subimage data/size
2877 129 common/image.c Can't get ramdisk load address
2878 -129 common/image.c Got ramdisk load address
2880 -130 common/cmd_doc.c Incorrect FIT image format
2881 131 common/cmd_doc.c FIT image format OK
2883 -140 common/cmd_ide.c Incorrect FIT image format
2884 141 common/cmd_ide.c FIT image format OK
2886 -150 common/cmd_nand.c Incorrect FIT image format
2887 151 common/cmd_nand.c FIT image format OK
2889 - FIT image support:
2891 Enable support for the FIT uImage format.
2893 CONFIG_FIT_BEST_MATCH
2894 When no configuration is explicitly selected, default to the
2895 one whose fdt's compatibility field best matches that of
2896 U-Boot itself. A match is considered "best" if it matches the
2897 most specific compatibility entry of U-Boot's fdt's root node.
2898 The order of entries in the configuration's fdt is ignored.
2900 CONFIG_FIT_SIGNATURE
2901 This option enables signature verification of FIT uImages,
2902 using a hash signed and verified using RSA. See
2903 doc/uImage.FIT/signature.txt for more details.
2905 - Standalone program support:
2906 CONFIG_STANDALONE_LOAD_ADDR
2908 This option defines a board specific value for the
2909 address where standalone program gets loaded, thus
2910 overwriting the architecture dependent default
2913 - Frame Buffer Address:
2916 Define CONFIG_FB_ADDR if you want to use specific
2917 address for frame buffer. This is typically the case
2918 when using a graphics controller has separate video
2919 memory. U-Boot will then place the frame buffer at
2920 the given address instead of dynamically reserving it
2921 in system RAM by calling lcd_setmem(), which grabs
2922 the memory for the frame buffer depending on the
2923 configured panel size.
2925 Please see board_init_f function.
2927 - Automatic software updates via TFTP server
2929 CONFIG_UPDATE_TFTP_CNT_MAX
2930 CONFIG_UPDATE_TFTP_MSEC_MAX
2932 These options enable and control the auto-update feature;
2933 for a more detailed description refer to doc/README.update.
2935 - MTD Support (mtdparts command, UBI support)
2938 Adds the MTD device infrastructure from the Linux kernel.
2939 Needed for mtdparts command support.
2941 CONFIG_MTD_PARTITIONS
2943 Adds the MTD partitioning infrastructure from the Linux
2944 kernel. Needed for UBI support.
2949 Adds commands for interacting with MTD partitions formatted
2950 with the UBI flash translation layer
2952 Requires also defining CONFIG_RBTREE
2954 CONFIG_UBI_SILENCE_MSG
2956 Make the verbose messages from UBI stop printing. This leaves
2957 warnings and errors enabled.
2962 Adds commands for interacting with UBI volumes formatted as
2963 UBIFS. UBIFS is read-only in u-boot.
2965 Requires UBI support as well as CONFIG_LZO
2967 CONFIG_UBIFS_SILENCE_MSG
2969 Make the verbose messages from UBIFS stop printing. This leaves
2970 warnings and errors enabled.
2974 Enable building of SPL globally.
2977 LDSCRIPT for linking the SPL binary.
2979 CONFIG_SPL_MAX_FOOTPRINT
2980 Maximum size in memory allocated to the SPL, BSS included.
2981 When defined, the linker checks that the actual memory
2982 used by SPL from _start to __bss_end does not exceed it.
2983 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2984 must not be both defined at the same time.
2987 Maximum size of the SPL image (text, data, rodata, and
2988 linker lists sections), BSS excluded.
2989 When defined, the linker checks that the actual size does
2992 CONFIG_SPL_TEXT_BASE
2993 TEXT_BASE for linking the SPL binary.
2995 CONFIG_SPL_RELOC_TEXT_BASE
2996 Address to relocate to. If unspecified, this is equal to
2997 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2999 CONFIG_SPL_BSS_START_ADDR
3000 Link address for the BSS within the SPL binary.
3002 CONFIG_SPL_BSS_MAX_SIZE
3003 Maximum size in memory allocated to the SPL BSS.
3004 When defined, the linker checks that the actual memory used
3005 by SPL from __bss_start to __bss_end does not exceed it.
3006 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
3007 must not be both defined at the same time.
3010 Adress of the start of the stack SPL will use
3012 CONFIG_SPL_RELOC_STACK
3013 Adress of the start of the stack SPL will use after
3014 relocation. If unspecified, this is equal to
3017 CONFIG_SYS_SPL_MALLOC_START
3018 Starting address of the malloc pool used in SPL.
3020 CONFIG_SYS_SPL_MALLOC_SIZE
3021 The size of the malloc pool used in SPL.
3023 CONFIG_SPL_FRAMEWORK
3024 Enable the SPL framework under common/. This framework
3025 supports MMC, NAND and YMODEM loading of U-Boot and NAND
3026 NAND loading of the Linux Kernel.
3028 CONFIG_SPL_DISPLAY_PRINT
3029 For ARM, enable an optional function to print more information
3030 about the running system.
3032 CONFIG_SPL_INIT_MINIMAL
3033 Arch init code should be built for a very small image
3035 CONFIG_SPL_LIBCOMMON_SUPPORT
3036 Support for common/libcommon.o in SPL binary
3038 CONFIG_SPL_LIBDISK_SUPPORT
3039 Support for disk/libdisk.o in SPL binary
3041 CONFIG_SPL_I2C_SUPPORT
3042 Support for drivers/i2c/libi2c.o in SPL binary
3044 CONFIG_SPL_GPIO_SUPPORT
3045 Support for drivers/gpio/libgpio.o in SPL binary
3047 CONFIG_SPL_MMC_SUPPORT
3048 Support for drivers/mmc/libmmc.o in SPL binary
3050 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
3051 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
3052 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
3053 Address, size and partition on the MMC to load U-Boot from
3054 when the MMC is being used in raw mode.
3056 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
3057 Sector to load kernel uImage from when MMC is being
3058 used in raw mode (for Falcon mode)
3060 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
3061 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
3062 Sector and number of sectors to load kernel argument
3063 parameters from when MMC is being used in raw mode
3066 CONFIG_SPL_FAT_SUPPORT
3067 Support for fs/fat/libfat.o in SPL binary
3069 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3070 Filename to read to load U-Boot when reading from FAT
3072 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3073 Filename to read to load kernel uImage when reading
3074 from FAT (for Falcon mode)
3076 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3077 Filename to read to load kernel argument parameters
3078 when reading from FAT (for Falcon mode)
3080 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3081 Set this for NAND SPL on PPC mpc83xx targets, so that
3082 start.S waits for the rest of the SPL to load before
3083 continuing (the hardware starts execution after just
3084 loading the first page rather than the full 4K).
3086 CONFIG_SPL_NAND_BASE
3087 Include nand_base.c in the SPL. Requires
3088 CONFIG_SPL_NAND_DRIVERS.
3090 CONFIG_SPL_NAND_DRIVERS
3091 SPL uses normal NAND drivers, not minimal drivers.
3094 Include standard software ECC in the SPL
3096 CONFIG_SPL_NAND_SIMPLE
3097 Support for NAND boot using simple NAND drivers that
3098 expose the cmd_ctrl() interface.
3100 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT
3101 Set for the SPL on PPC mpc8xxx targets, support for
3102 arch/powerpc/cpu/mpc8xxx/ddr/libddr.o in SPL binary.
3104 CONFIG_SPL_COMMON_INIT_DDR
3105 Set for common ddr init with serial presence detect in
3108 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3109 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3110 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3111 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3112 CONFIG_SYS_NAND_ECCBYTES
3113 Defines the size and behavior of the NAND that SPL uses
3116 CONFIG_SYS_NAND_U_BOOT_OFFS
3117 Location in NAND to read U-Boot from
3119 CONFIG_SYS_NAND_U_BOOT_DST
3120 Location in memory to load U-Boot to
3122 CONFIG_SYS_NAND_U_BOOT_SIZE
3123 Size of image to load
3125 CONFIG_SYS_NAND_U_BOOT_START
3126 Entry point in loaded image to jump to
3128 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3129 Define this if you need to first read the OOB and then the
3130 data. This is used for example on davinci plattforms.
3132 CONFIG_SPL_OMAP3_ID_NAND
3133 Support for an OMAP3-specific set of functions to return the
3134 ID and MFR of the first attached NAND chip, if present.
3136 CONFIG_SPL_SERIAL_SUPPORT
3137 Support for drivers/serial/libserial.o in SPL binary
3139 CONFIG_SPL_SPI_FLASH_SUPPORT
3140 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3142 CONFIG_SPL_SPI_SUPPORT
3143 Support for drivers/spi/libspi.o in SPL binary
3145 CONFIG_SPL_RAM_DEVICE
3146 Support for running image already present in ram, in SPL binary
3148 CONFIG_SPL_LIBGENERIC_SUPPORT
3149 Support for lib/libgeneric.o in SPL binary
3151 CONFIG_SPL_ENV_SUPPORT
3152 Support for the environment operating in SPL binary
3154 CONFIG_SPL_NET_SUPPORT
3155 Support for the net/libnet.o in SPL binary.
3156 It conflicts with SPL env from storage medium specified by
3157 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3160 Image offset to which the SPL should be padded before appending
3161 the SPL payload. By default, this is defined as
3162 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3163 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3164 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3167 Final target image containing SPL and payload. Some SPLs
3168 use an arch-specific makefile fragment instead, for
3169 example if more than one image needs to be produced.
3171 CONFIG_FIT_SPL_PRINT
3172 Printing information about a FIT image adds quite a bit of
3173 code to SPL. So this is normally disabled in SPL. Use this
3174 option to re-enable it. This will affect the output of the
3175 bootm command when booting a FIT image.
3179 Enable building of TPL globally.
3182 Image offset to which the TPL should be padded before appending
3183 the TPL payload. By default, this is defined as
3184 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3185 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3186 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3191 [so far only for SMDK2400 boards]
3193 - Modem support enable:
3194 CONFIG_MODEM_SUPPORT
3196 - RTS/CTS Flow control enable:
3199 - Modem debug support:
3200 CONFIG_MODEM_SUPPORT_DEBUG
3202 Enables debugging stuff (char screen[1024], dbg())
3203 for modem support. Useful only with BDI2000.
3205 - Interrupt support (PPC):
3207 There are common interrupt_init() and timer_interrupt()
3208 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3209 for CPU specific initialization. interrupt_init_cpu()
3210 should set decrementer_count to appropriate value. If
3211 CPU resets decrementer automatically after interrupt
3212 (ppc4xx) it should set decrementer_count to zero.
3213 timer_interrupt() calls timer_interrupt_cpu() for CPU
3214 specific handling. If board has watchdog / status_led
3215 / other_activity_monitor it works automatically from
3216 general timer_interrupt().
3220 In the target system modem support is enabled when a
3221 specific key (key combination) is pressed during
3222 power-on. Otherwise U-Boot will boot normally
3223 (autoboot). The key_pressed() function is called from
3224 board_init(). Currently key_pressed() is a dummy
3225 function, returning 1 and thus enabling modem
3228 If there are no modem init strings in the
3229 environment, U-Boot proceed to autoboot; the
3230 previous output (banner, info printfs) will be
3233 See also: doc/README.Modem
3235 Board initialization settings:
3236 ------------------------------
3238 During Initialization u-boot calls a number of board specific functions
3239 to allow the preparation of board specific prerequisites, e.g. pin setup
3240 before drivers are initialized. To enable these callbacks the
3241 following configuration macros have to be defined. Currently this is
3242 architecture specific, so please check arch/your_architecture/lib/board.c
3243 typically in board_init_f() and board_init_r().
3245 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3246 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3247 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3248 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3250 Configuration Settings:
3251 -----------------------
3253 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3254 undefine this when you're short of memory.
3256 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3257 width of the commands listed in the 'help' command output.
3259 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3260 prompt for user input.
3262 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3264 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3266 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3268 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3269 the application (usually a Linux kernel) when it is
3272 - CONFIG_SYS_BAUDRATE_TABLE:
3273 List of legal baudrate settings for this board.
3275 - CONFIG_SYS_CONSOLE_INFO_QUIET
3276 Suppress display of console information at boot.
3278 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3279 If the board specific function
3280 extern int overwrite_console (void);
3281 returns 1, the stdin, stderr and stdout are switched to the
3282 serial port, else the settings in the environment are used.
3284 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3285 Enable the call to overwrite_console().
3287 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3288 Enable overwrite of previous console environment settings.
3290 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3291 Begin and End addresses of the area used by the
3294 - CONFIG_SYS_ALT_MEMTEST:
3295 Enable an alternate, more extensive memory test.
3297 - CONFIG_SYS_MEMTEST_SCRATCH:
3298 Scratch address used by the alternate memory test
3299 You only need to set this if address zero isn't writeable
3301 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3302 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3303 this specified memory area will get subtracted from the top
3304 (end) of RAM and won't get "touched" at all by U-Boot. By
3305 fixing up gd->ram_size the Linux kernel should gets passed
3306 the now "corrected" memory size and won't touch it either.
3307 This should work for arch/ppc and arch/powerpc. Only Linux
3308 board ports in arch/powerpc with bootwrapper support that
3309 recalculate the memory size from the SDRAM controller setup
3310 will have to get fixed in Linux additionally.
3312 This option can be used as a workaround for the 440EPx/GRx
3313 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3316 WARNING: Please make sure that this value is a multiple of
3317 the Linux page size (normally 4k). If this is not the case,
3318 then the end address of the Linux memory will be located at a
3319 non page size aligned address and this could cause major
3322 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3323 Enable temporary baudrate change while serial download
3325 - CONFIG_SYS_SDRAM_BASE:
3326 Physical start address of SDRAM. _Must_ be 0 here.
3328 - CONFIG_SYS_MBIO_BASE:
3329 Physical start address of Motherboard I/O (if using a
3332 - CONFIG_SYS_FLASH_BASE:
3333 Physical start address of Flash memory.
3335 - CONFIG_SYS_MONITOR_BASE:
3336 Physical start address of boot monitor code (set by
3337 make config files to be same as the text base address
3338 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3339 CONFIG_SYS_FLASH_BASE when booting from flash.
3341 - CONFIG_SYS_MONITOR_LEN:
3342 Size of memory reserved for monitor code, used to
3343 determine _at_compile_time_ (!) if the environment is
3344 embedded within the U-Boot image, or in a separate
3347 - CONFIG_SYS_MALLOC_LEN:
3348 Size of DRAM reserved for malloc() use.
3350 - CONFIG_SYS_BOOTM_LEN:
3351 Normally compressed uImages are limited to an
3352 uncompressed size of 8 MBytes. If this is not enough,
3353 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3354 to adjust this setting to your needs.
3356 - CONFIG_SYS_BOOTMAPSZ:
3357 Maximum size of memory mapped by the startup code of
3358 the Linux kernel; all data that must be processed by
3359 the Linux kernel (bd_info, boot arguments, FDT blob if
3360 used) must be put below this limit, unless "bootm_low"
3361 enviroment variable is defined and non-zero. In such case
3362 all data for the Linux kernel must be between "bootm_low"
3363 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3364 variable "bootm_mapsize" will override the value of
3365 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3366 then the value in "bootm_size" will be used instead.
3368 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3369 Enable initrd_high functionality. If defined then the
3370 initrd_high feature is enabled and the bootm ramdisk subcommand
3373 - CONFIG_SYS_BOOT_GET_CMDLINE:
3374 Enables allocating and saving kernel cmdline in space between
3375 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3377 - CONFIG_SYS_BOOT_GET_KBD:
3378 Enables allocating and saving a kernel copy of the bd_info in
3379 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3381 - CONFIG_SYS_MAX_FLASH_BANKS:
3382 Max number of Flash memory banks
3384 - CONFIG_SYS_MAX_FLASH_SECT:
3385 Max number of sectors on a Flash chip
3387 - CONFIG_SYS_FLASH_ERASE_TOUT:
3388 Timeout for Flash erase operations (in ms)
3390 - CONFIG_SYS_FLASH_WRITE_TOUT:
3391 Timeout for Flash write operations (in ms)
3393 - CONFIG_SYS_FLASH_LOCK_TOUT
3394 Timeout for Flash set sector lock bit operation (in ms)
3396 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3397 Timeout for Flash clear lock bits operation (in ms)
3399 - CONFIG_SYS_FLASH_PROTECTION
3400 If defined, hardware flash sectors protection is used
3401 instead of U-Boot software protection.
3403 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3405 Enable TFTP transfers directly to flash memory;
3406 without this option such a download has to be
3407 performed in two steps: (1) download to RAM, and (2)
3408 copy from RAM to flash.
3410 The two-step approach is usually more reliable, since
3411 you can check if the download worked before you erase
3412 the flash, but in some situations (when system RAM is
3413 too limited to allow for a temporary copy of the
3414 downloaded image) this option may be very useful.
3416 - CONFIG_SYS_FLASH_CFI:
3417 Define if the flash driver uses extra elements in the
3418 common flash structure for storing flash geometry.
3420 - CONFIG_FLASH_CFI_DRIVER
3421 This option also enables the building of the cfi_flash driver
3422 in the drivers directory
3424 - CONFIG_FLASH_CFI_MTD
3425 This option enables the building of the cfi_mtd driver
3426 in the drivers directory. The driver exports CFI flash
3429 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3430 Use buffered writes to flash.
3432 - CONFIG_FLASH_SPANSION_S29WS_N
3433 s29ws-n MirrorBit flash has non-standard addresses for buffered
3436 - CONFIG_SYS_FLASH_QUIET_TEST
3437 If this option is defined, the common CFI flash doesn't
3438 print it's warning upon not recognized FLASH banks. This
3439 is useful, if some of the configured banks are only
3440 optionally available.
3442 - CONFIG_FLASH_SHOW_PROGRESS
3443 If defined (must be an integer), print out countdown
3444 digits and dots. Recommended value: 45 (9..1) for 80
3445 column displays, 15 (3..1) for 40 column displays.
3447 - CONFIG_FLASH_VERIFY
3448 If defined, the content of the flash (destination) is compared
3449 against the source after the write operation. An error message
3450 will be printed when the contents are not identical.
3451 Please note that this option is useless in nearly all cases,
3452 since such flash programming errors usually are detected earlier
3453 while unprotecting/erasing/programming. Please only enable
3454 this option if you really know what you are doing.
3456 - CONFIG_SYS_RX_ETH_BUFFER:
3457 Defines the number of Ethernet receive buffers. On some
3458 Ethernet controllers it is recommended to set this value
3459 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3460 buffers can be full shortly after enabling the interface
3461 on high Ethernet traffic.
3462 Defaults to 4 if not defined.
3464 - CONFIG_ENV_MAX_ENTRIES
3466 Maximum number of entries in the hash table that is used
3467 internally to store the environment settings. The default
3468 setting is supposed to be generous and should work in most
3469 cases. This setting can be used to tune behaviour; see
3470 lib/hashtable.c for details.
3472 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3473 - CONFIG_ENV_FLAGS_LIST_STATIC
3474 Enable validation of the values given to enviroment variables when
3475 calling env set. Variables can be restricted to only decimal,
3476 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3477 the variables can also be restricted to IP address or MAC address.
3479 The format of the list is:
3480 type_attribute = [s|d|x|b|i|m]
3481 access_atribute = [a|r|o|c]
3482 attributes = type_attribute[access_atribute]
3483 entry = variable_name[:attributes]
3486 The type attributes are:
3487 s - String (default)
3490 b - Boolean ([1yYtT|0nNfF])
3494 The access attributes are:
3500 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3501 Define this to a list (string) to define the ".flags"
3502 envirnoment variable in the default or embedded environment.
3504 - CONFIG_ENV_FLAGS_LIST_STATIC
3505 Define this to a list (string) to define validation that
3506 should be done if an entry is not found in the ".flags"
3507 environment variable. To override a setting in the static
3508 list, simply add an entry for the same variable name to the
3511 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3512 If defined, don't allow the -f switch to env set override variable
3515 - CONFIG_SYS_GENERIC_BOARD
3516 This selects the architecture-generic board system instead of the
3517 architecture-specific board files. It is intended to move boards
3518 to this new framework over time. Defining this will disable the
3519 arch/foo/lib/board.c file and use common/board_f.c and
3520 common/board_r.c instead. To use this option your architecture
3521 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3522 its config.mk file). If you find problems enabling this option on
3523 your board please report the problem and send patches!
3525 - CONFIG_SYS_SYM_OFFSETS
3526 This is set by architectures that use offsets for link symbols
3527 instead of absolute values. So bss_start is obtained using an
3528 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3529 directly. You should not need to touch this setting.
3531 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3532 This is set by OMAP boards for the max time that reset should
3533 be asserted. See doc/README.omap-reset-time for details on how
3534 the value can be calulated on a given board.
3536 The following definitions that deal with the placement and management
3537 of environment data (variable area); in general, we support the
3538 following configurations:
3540 - CONFIG_BUILD_ENVCRC:
3542 Builds up envcrc with the target environment so that external utils
3543 may easily extract it and embed it in final U-Boot images.
3545 - CONFIG_ENV_IS_IN_FLASH:
3547 Define this if the environment is in flash memory.
3549 a) The environment occupies one whole flash sector, which is
3550 "embedded" in the text segment with the U-Boot code. This
3551 happens usually with "bottom boot sector" or "top boot
3552 sector" type flash chips, which have several smaller
3553 sectors at the start or the end. For instance, such a
3554 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3555 such a case you would place the environment in one of the
3556 4 kB sectors - with U-Boot code before and after it. With
3557 "top boot sector" type flash chips, you would put the
3558 environment in one of the last sectors, leaving a gap
3559 between U-Boot and the environment.
3561 - CONFIG_ENV_OFFSET:
3563 Offset of environment data (variable area) to the
3564 beginning of flash memory; for instance, with bottom boot
3565 type flash chips the second sector can be used: the offset
3566 for this sector is given here.
3568 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3572 This is just another way to specify the start address of
3573 the flash sector containing the environment (instead of
3576 - CONFIG_ENV_SECT_SIZE:
3578 Size of the sector containing the environment.
3581 b) Sometimes flash chips have few, equal sized, BIG sectors.
3582 In such a case you don't want to spend a whole sector for
3587 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3588 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3589 of this flash sector for the environment. This saves
3590 memory for the RAM copy of the environment.
3592 It may also save flash memory if you decide to use this
3593 when your environment is "embedded" within U-Boot code,
3594 since then the remainder of the flash sector could be used
3595 for U-Boot code. It should be pointed out that this is
3596 STRONGLY DISCOURAGED from a robustness point of view:
3597 updating the environment in flash makes it always
3598 necessary to erase the WHOLE sector. If something goes
3599 wrong before the contents has been restored from a copy in
3600 RAM, your target system will be dead.
3602 - CONFIG_ENV_ADDR_REDUND
3603 CONFIG_ENV_SIZE_REDUND
3605 These settings describe a second storage area used to hold
3606 a redundant copy of the environment data, so that there is
3607 a valid backup copy in case there is a power failure during
3608 a "saveenv" operation.
3610 BE CAREFUL! Any changes to the flash layout, and some changes to the
3611 source code will make it necessary to adapt <board>/u-boot.lds*
3615 - CONFIG_ENV_IS_IN_NVRAM:
3617 Define this if you have some non-volatile memory device
3618 (NVRAM, battery buffered SRAM) which you want to use for the
3624 These two #defines are used to determine the memory area you
3625 want to use for environment. It is assumed that this memory
3626 can just be read and written to, without any special
3629 BE CAREFUL! The first access to the environment happens quite early
3630 in U-Boot initalization (when we try to get the setting of for the
3631 console baudrate). You *MUST* have mapped your NVRAM area then, or
3634 Please note that even with NVRAM we still use a copy of the
3635 environment in RAM: we could work on NVRAM directly, but we want to
3636 keep settings there always unmodified except somebody uses "saveenv"
3637 to save the current settings.
3640 - CONFIG_ENV_IS_IN_EEPROM:
3642 Use this if you have an EEPROM or similar serial access
3643 device and a driver for it.
3645 - CONFIG_ENV_OFFSET:
3648 These two #defines specify the offset and size of the
3649 environment area within the total memory of your EEPROM.
3651 - CONFIG_SYS_I2C_EEPROM_ADDR:
3652 If defined, specified the chip address of the EEPROM device.
3653 The default address is zero.
3655 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3656 If defined, the number of bits used to address bytes in a
3657 single page in the EEPROM device. A 64 byte page, for example
3658 would require six bits.
3660 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3661 If defined, the number of milliseconds to delay between
3662 page writes. The default is zero milliseconds.
3664 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3665 The length in bytes of the EEPROM memory array address. Note
3666 that this is NOT the chip address length!
3668 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3669 EEPROM chips that implement "address overflow" are ones
3670 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3671 address and the extra bits end up in the "chip address" bit
3672 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3675 Note that we consider the length of the address field to
3676 still be one byte because the extra address bits are hidden
3677 in the chip address.
3679 - CONFIG_SYS_EEPROM_SIZE:
3680 The size in bytes of the EEPROM device.
3682 - CONFIG_ENV_EEPROM_IS_ON_I2C
3683 define this, if you have I2C and SPI activated, and your
3684 EEPROM, which holds the environment, is on the I2C bus.
3686 - CONFIG_I2C_ENV_EEPROM_BUS
3687 if you have an Environment on an EEPROM reached over
3688 I2C muxes, you can define here, how to reach this
3689 EEPROM. For example:
3691 #define CONFIG_I2C_ENV_EEPROM_BUS 1
3693 EEPROM which holds the environment, is reached over
3694 a pca9547 i2c mux with address 0x70, channel 3.
3696 - CONFIG_ENV_IS_IN_DATAFLASH:
3698 Define this if you have a DataFlash memory device which you
3699 want to use for the environment.
3701 - CONFIG_ENV_OFFSET:
3705 These three #defines specify the offset and size of the
3706 environment area within the total memory of your DataFlash placed
3707 at the specified address.
3709 - CONFIG_ENV_IS_IN_REMOTE:
3711 Define this if you have a remote memory space which you
3712 want to use for the local device's environment.
3717 These two #defines specify the address and size of the
3718 environment area within the remote memory space. The
3719 local device can get the environment from remote memory
3720 space by SRIO or PCIE links.
3722 BE CAREFUL! For some special cases, the local device can not use
3723 "saveenv" command. For example, the local device will get the
3724 environment stored in a remote NOR flash by SRIO or PCIE link,
3725 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3727 - CONFIG_ENV_IS_IN_NAND:
3729 Define this if you have a NAND device which you want to use
3730 for the environment.
3732 - CONFIG_ENV_OFFSET:
3735 These two #defines specify the offset and size of the environment
3736 area within the first NAND device. CONFIG_ENV_OFFSET must be
3737 aligned to an erase block boundary.
3739 - CONFIG_ENV_OFFSET_REDUND (optional):
3741 This setting describes a second storage area of CONFIG_ENV_SIZE
3742 size used to hold a redundant copy of the environment data, so
3743 that there is a valid backup copy in case there is a power failure
3744 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3745 aligned to an erase block boundary.
3747 - CONFIG_ENV_RANGE (optional):
3749 Specifies the length of the region in which the environment
3750 can be written. This should be a multiple of the NAND device's
3751 block size. Specifying a range with more erase blocks than
3752 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3753 the range to be avoided.
3755 - CONFIG_ENV_OFFSET_OOB (optional):
3757 Enables support for dynamically retrieving the offset of the
3758 environment from block zero's out-of-band data. The
3759 "nand env.oob" command can be used to record this offset.
3760 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3761 using CONFIG_ENV_OFFSET_OOB.
3763 - CONFIG_NAND_ENV_DST
3765 Defines address in RAM to which the nand_spl code should copy the
3766 environment. If redundant environment is used, it will be copied to
3767 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3769 - CONFIG_ENV_IS_IN_UBI:
3771 Define this if you have an UBI volume that you want to use for the
3772 environment. This has the benefit of wear-leveling the environment
3773 accesses, which is important on NAND.
3775 - CONFIG_ENV_UBI_PART:
3777 Define this to a string that is the mtd partition containing the UBI.
3779 - CONFIG_ENV_UBI_VOLUME:
3781 Define this to the name of the volume that you want to store the
3784 - CONFIG_ENV_UBI_VOLUME_REDUND:
3786 Define this to the name of another volume to store a second copy of
3787 the environment in. This will enable redundant environments in UBI.
3788 It is assumed that both volumes are in the same MTD partition.
3790 - CONFIG_UBI_SILENCE_MSG
3791 - CONFIG_UBIFS_SILENCE_MSG
3793 You will probably want to define these to avoid a really noisy system
3794 when storing the env in UBI.
3796 - CONFIG_ENV_IS_IN_MMC:
3798 Define this if you have an MMC device which you want to use for the
3801 - CONFIG_SYS_MMC_ENV_DEV:
3803 Specifies which MMC device the environment is stored in.
3805 - CONFIG_SYS_MMC_ENV_PART (optional):
3807 Specifies which MMC partition the environment is stored in. If not
3808 set, defaults to partition 0, the user area. Common values might be
3809 1 (first MMC boot partition), 2 (second MMC boot partition).
3811 - CONFIG_ENV_OFFSET:
3814 These two #defines specify the offset and size of the environment
3815 area within the specified MMC device.
3817 If offset is positive (the usual case), it is treated as relative to
3818 the start of the MMC partition. If offset is negative, it is treated
3819 as relative to the end of the MMC partition. This can be useful if
3820 your board may be fitted with different MMC devices, which have
3821 different sizes for the MMC partitions, and you always want the
3822 environment placed at the very end of the partition, to leave the
3823 maximum possible space before it, to store other data.
3825 These two values are in units of bytes, but must be aligned to an
3826 MMC sector boundary.
3828 - CONFIG_ENV_OFFSET_REDUND (optional):
3830 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3831 hold a redundant copy of the environment data. This provides a
3832 valid backup copy in case the other copy is corrupted, e.g. due
3833 to a power failure during a "saveenv" operation.
3835 This value may also be positive or negative; this is handled in the
3836 same way as CONFIG_ENV_OFFSET.
3838 This value is also in units of bytes, but must also be aligned to
3839 an MMC sector boundary.
3841 - CONFIG_ENV_SIZE_REDUND (optional):
3843 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3844 set. If this value is set, it must be set to the same value as
3847 - CONFIG_SYS_SPI_INIT_OFFSET
3849 Defines offset to the initial SPI buffer area in DPRAM. The
3850 area is used at an early stage (ROM part) if the environment
3851 is configured to reside in the SPI EEPROM: We need a 520 byte
3852 scratch DPRAM area. It is used between the two initialization
3853 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3854 to be a good choice since it makes it far enough from the
3855 start of the data area as well as from the stack pointer.
3857 Please note that the environment is read-only until the monitor
3858 has been relocated to RAM and a RAM copy of the environment has been
3859 created; also, when using EEPROM you will have to use getenv_f()
3860 until then to read environment variables.
3862 The environment is protected by a CRC32 checksum. Before the monitor
3863 is relocated into RAM, as a result of a bad CRC you will be working
3864 with the compiled-in default environment - *silently*!!! [This is
3865 necessary, because the first environment variable we need is the
3866 "baudrate" setting for the console - if we have a bad CRC, we don't
3867 have any device yet where we could complain.]
3869 Note: once the monitor has been relocated, then it will complain if
3870 the default environment is used; a new CRC is computed as soon as you
3871 use the "saveenv" command to store a valid environment.
3873 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3874 Echo the inverted Ethernet link state to the fault LED.
3876 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3877 also needs to be defined.
3879 - CONFIG_SYS_FAULT_MII_ADDR:
3880 MII address of the PHY to check for the Ethernet link state.
3882 - CONFIG_NS16550_MIN_FUNCTIONS:
3883 Define this if you desire to only have use of the NS16550_init
3884 and NS16550_putc functions for the serial driver located at
3885 drivers/serial/ns16550.c. This option is useful for saving
3886 space for already greatly restricted images, including but not
3887 limited to NAND_SPL configurations.
3889 - CONFIG_DISPLAY_BOARDINFO
3890 Display information about the board that U-Boot is running on
3891 when U-Boot starts up. The board function checkboard() is called
3894 - CONFIG_DISPLAY_BOARDINFO_LATE
3895 Similar to the previous option, but display this information
3896 later, once stdio is running and output goes to the LCD, if
3899 Low Level (hardware related) configuration options:
3900 ---------------------------------------------------
3902 - CONFIG_SYS_CACHELINE_SIZE:
3903 Cache Line Size of the CPU.
3905 - CONFIG_SYS_DEFAULT_IMMR:
3906 Default address of the IMMR after system reset.
3908 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3909 and RPXsuper) to be able to adjust the position of
3910 the IMMR register after a reset.
3912 - CONFIG_SYS_CCSRBAR_DEFAULT:
3913 Default (power-on reset) physical address of CCSR on Freescale
3916 - CONFIG_SYS_CCSRBAR:
3917 Virtual address of CCSR. On a 32-bit build, this is typically
3918 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3920 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3921 for cross-platform code that uses that macro instead.
3923 - CONFIG_SYS_CCSRBAR_PHYS:
3924 Physical address of CCSR. CCSR can be relocated to a new
3925 physical address, if desired. In this case, this macro should
3926 be set to that address. Otherwise, it should be set to the
3927 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3928 is typically relocated on 36-bit builds. It is recommended
3929 that this macro be defined via the _HIGH and _LOW macros:
3931 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3932 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3934 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3935 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3936 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3937 used in assembly code, so it must not contain typecasts or
3938 integer size suffixes (e.g. "ULL").
3940 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3941 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3942 used in assembly code, so it must not contain typecasts or
3943 integer size suffixes (e.g. "ULL").
3945 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3946 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3947 forced to a value that ensures that CCSR is not relocated.
3949 - Floppy Disk Support:
3950 CONFIG_SYS_FDC_DRIVE_NUMBER
3952 the default drive number (default value 0)
3954 CONFIG_SYS_ISA_IO_STRIDE
3956 defines the spacing between FDC chipset registers
3959 CONFIG_SYS_ISA_IO_OFFSET
3961 defines the offset of register from address. It
3962 depends on which part of the data bus is connected to
3963 the FDC chipset. (default value 0)
3965 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3966 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3969 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3970 fdc_hw_init() is called at the beginning of the FDC
3971 setup. fdc_hw_init() must be provided by the board
3972 source code. It is used to make hardware dependant
3976 Most IDE controllers were designed to be connected with PCI
3977 interface. Only few of them were designed for AHB interface.
3978 When software is doing ATA command and data transfer to
3979 IDE devices through IDE-AHB controller, some additional
3980 registers accessing to these kind of IDE-AHB controller
3983 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3984 DO NOT CHANGE unless you know exactly what you're
3985 doing! (11-4) [MPC8xx/82xx systems only]
3987 - CONFIG_SYS_INIT_RAM_ADDR:
3989 Start address of memory area that can be used for
3990 initial data and stack; please note that this must be
3991 writable memory that is working WITHOUT special
3992 initialization, i. e. you CANNOT use normal RAM which
3993 will become available only after programming the
3994 memory controller and running certain initialization
3997 U-Boot uses the following memory types:
3998 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3999 - MPC824X: data cache
4000 - PPC4xx: data cache
4002 - CONFIG_SYS_GBL_DATA_OFFSET:
4004 Offset of the initial data structure in the memory
4005 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
4006 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
4007 data is located at the end of the available space
4008 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
4009 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
4010 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
4011 CONFIG_SYS_GBL_DATA_OFFSET) downward.
4014 On the MPC824X (or other systems that use the data
4015 cache for initial memory) the address chosen for
4016 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
4017 point to an otherwise UNUSED address space between
4018 the top of RAM and the start of the PCI space.
4020 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
4022 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
4024 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
4026 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
4028 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
4030 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
4032 - CONFIG_SYS_OR_TIMING_SDRAM:
4035 - CONFIG_SYS_MAMR_PTA:
4036 periodic timer for refresh
4038 - CONFIG_SYS_DER: Debug Event Register (37-47)
4040 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
4041 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
4042 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
4043 CONFIG_SYS_BR1_PRELIM:
4044 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
4046 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
4047 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
4048 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
4049 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
4051 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
4052 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
4053 Machine Mode Register and Memory Periodic Timer
4054 Prescaler definitions (SDRAM timing)
4056 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
4057 enable I2C microcode relocation patch (MPC8xx);
4058 define relocation offset in DPRAM [DSP2]
4060 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
4061 enable SMC microcode relocation patch (MPC8xx);
4062 define relocation offset in DPRAM [SMC1]
4064 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
4065 enable SPI microcode relocation patch (MPC8xx);
4066 define relocation offset in DPRAM [SCC4]
4068 - CONFIG_SYS_USE_OSCCLK:
4069 Use OSCM clock mode on MBX8xx board. Be careful,
4070 wrong setting might damage your board. Read
4071 doc/README.MBX before setting this variable!
4073 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
4074 Offset of the bootmode word in DPRAM used by post
4075 (Power On Self Tests). This definition overrides
4076 #define'd default value in commproc.h resp.
4079 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
4080 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
4081 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
4082 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
4083 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
4084 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
4085 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
4086 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4087 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4089 - CONFIG_PCI_DISABLE_PCIE:
4090 Disable PCI-Express on systems where it is supported but not
4093 - CONFIG_PCI_ENUM_ONLY
4094 Only scan through and get the devices on the busses.
4095 Don't do any setup work, presumably because someone or
4096 something has already done it, and we don't need to do it
4097 a second time. Useful for platforms that are pre-booted
4098 by coreboot or similar.
4100 - CONFIG_PCI_INDIRECT_BRIDGE:
4101 Enable support for indirect PCI bridges.
4104 Chip has SRIO or not
4107 Board has SRIO 1 port available
4110 Board has SRIO 2 port available
4112 - CONFIG_SRIO_PCIE_BOOT_MASTER
4113 Board can support master function for Boot from SRIO and PCIE
4115 - CONFIG_SYS_SRIOn_MEM_VIRT:
4116 Virtual Address of SRIO port 'n' memory region
4118 - CONFIG_SYS_SRIOn_MEM_PHYS:
4119 Physical Address of SRIO port 'n' memory region
4121 - CONFIG_SYS_SRIOn_MEM_SIZE:
4122 Size of SRIO port 'n' memory region
4124 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4125 Defined to tell the NAND controller that the NAND chip is using
4127 Not all NAND drivers use this symbol.
4128 Example of drivers that use it:
4129 - drivers/mtd/nand/ndfc.c
4130 - drivers/mtd/nand/mxc_nand.c
4132 - CONFIG_SYS_NDFC_EBC0_CFG
4133 Sets the EBC0_CFG register for the NDFC. If not defined
4134 a default value will be used.
4137 Get DDR timing information from an I2C EEPROM. Common
4138 with pluggable memory modules such as SODIMMs
4141 I2C address of the SPD EEPROM
4143 - CONFIG_SYS_SPD_BUS_NUM
4144 If SPD EEPROM is on an I2C bus other than the first
4145 one, specify here. Note that the value must resolve
4146 to something your driver can deal with.
4148 - CONFIG_SYS_DDR_RAW_TIMING
4149 Get DDR timing information from other than SPD. Common with
4150 soldered DDR chips onboard without SPD. DDR raw timing
4151 parameters are extracted from datasheet and hard-coded into
4152 header files or board specific files.
4154 - CONFIG_FSL_DDR_INTERACTIVE
4155 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4157 - CONFIG_SYS_83XX_DDR_USES_CS0
4158 Only for 83xx systems. If specified, then DDR should
4159 be configured using CS0 and CS1 instead of CS2 and CS3.
4161 - CONFIG_ETHER_ON_FEC[12]
4162 Define to enable FEC[12] on a 8xx series processor.
4164 - CONFIG_FEC[12]_PHY
4165 Define to the hardcoded PHY address which corresponds
4166 to the given FEC; i. e.
4167 #define CONFIG_FEC1_PHY 4
4168 means that the PHY with address 4 is connected to FEC1
4170 When set to -1, means to probe for first available.
4172 - CONFIG_FEC[12]_PHY_NORXERR
4173 The PHY does not have a RXERR line (RMII only).
4174 (so program the FEC to ignore it).
4177 Enable RMII mode for all FECs.
4178 Note that this is a global option, we can't
4179 have one FEC in standard MII mode and another in RMII mode.
4181 - CONFIG_CRC32_VERIFY
4182 Add a verify option to the crc32 command.
4185 => crc32 -v <address> <count> <crc32>
4187 Where address/count indicate a memory area
4188 and crc32 is the correct crc32 which the
4192 Add the "loopw" memory command. This only takes effect if
4193 the memory commands are activated globally (CONFIG_CMD_MEM).
4196 Add the "mdc" and "mwc" memory commands. These are cyclic
4201 This command will print 4 bytes (10,11,12,13) each 500 ms.
4203 => mwc.l 100 12345678 10
4204 This command will write 12345678 to address 100 all 10 ms.
4206 This only takes effect if the memory commands are activated
4207 globally (CONFIG_CMD_MEM).
4209 - CONFIG_SKIP_LOWLEVEL_INIT
4210 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4211 low level initializations (like setting up the memory
4212 controller) are omitted and/or U-Boot does not
4213 relocate itself into RAM.
4215 Normally this variable MUST NOT be defined. The only
4216 exception is when U-Boot is loaded (to RAM) by some
4217 other boot loader or by a debugger which performs
4218 these initializations itself.
4221 Modifies the behaviour of start.S when compiling a loader
4222 that is executed before the actual U-Boot. E.g. when
4223 compiling a NAND SPL.
4226 Modifies the behaviour of start.S when compiling a loader
4227 that is executed after the SPL and before the actual U-Boot.
4228 It is loaded by the SPL.
4230 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4231 Only for 85xx systems. If this variable is specified, the section
4232 .resetvec is not kept and the section .bootpg is placed in the
4233 previous 4k of the .text section.
4235 - CONFIG_ARCH_MAP_SYSMEM
4236 Generally U-Boot (and in particular the md command) uses
4237 effective address. It is therefore not necessary to regard
4238 U-Boot address as virtual addresses that need to be translated
4239 to physical addresses. However, sandbox requires this, since
4240 it maintains its own little RAM buffer which contains all
4241 addressable memory. This option causes some memory accesses
4242 to be mapped through map_sysmem() / unmap_sysmem().
4244 - CONFIG_USE_ARCH_MEMCPY
4245 CONFIG_USE_ARCH_MEMSET
4246 If these options are used a optimized version of memcpy/memset will
4247 be used if available. These functions may be faster under some
4248 conditions but may increase the binary size.
4250 - CONFIG_X86_RESET_VECTOR
4251 If defined, the x86 reset vector code is included. This is not
4252 needed when U-Boot is running from Coreboot.
4255 Defines the MPU clock speed (in MHz).
4257 NOTE : currently only supported on AM335x platforms.
4259 Freescale QE/FMAN Firmware Support:
4260 -----------------------------------
4262 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4263 loading of "firmware", which is encoded in the QE firmware binary format.
4264 This firmware often needs to be loaded during U-Boot booting, so macros
4265 are used to identify the storage device (NOR flash, SPI, etc) and the address
4268 - CONFIG_SYS_QE_FMAN_FW_ADDR
4269 The address in the storage device where the firmware is located. The
4270 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4273 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4274 The maximum possible size of the firmware. The firmware binary format
4275 has a field that specifies the actual size of the firmware, but it
4276 might not be possible to read any part of the firmware unless some
4277 local storage is allocated to hold the entire firmware first.
4279 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4280 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4281 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4282 virtual address in NOR flash.
4284 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4285 Specifies that QE/FMAN firmware is located in NAND flash.
4286 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4288 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4289 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4290 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4292 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4293 Specifies that QE/FMAN firmware is located on the primary SPI
4294 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4296 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4297 Specifies that QE/FMAN firmware is located in the remote (master)
4298 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4299 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4300 window->master inbound window->master LAW->the ucode address in
4301 master's memory space.
4303 Building the Software:
4304 ======================
4306 Building U-Boot has been tested in several native build environments
4307 and in many different cross environments. Of course we cannot support
4308 all possibly existing versions of cross development tools in all
4309 (potentially obsolete) versions. In case of tool chain problems we
4310 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4311 which is extensively used to build and test U-Boot.
4313 If you are not using a native environment, it is assumed that you
4314 have GNU cross compiling tools available in your path. In this case,
4315 you must set the environment variable CROSS_COMPILE in your shell.
4316 Note that no changes to the Makefile or any other source files are
4317 necessary. For example using the ELDK on a 4xx CPU, please enter:
4319 $ CROSS_COMPILE=ppc_4xx-
4320 $ export CROSS_COMPILE
4322 Note: If you wish to generate Windows versions of the utilities in
4323 the tools directory you can use the MinGW toolchain
4324 (http://www.mingw.org). Set your HOST tools to the MinGW
4325 toolchain and execute 'make tools'. For example:
4327 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4329 Binaries such as tools/mkimage.exe will be created which can
4330 be executed on computers running Windows.
4332 U-Boot is intended to be simple to build. After installing the
4333 sources you must configure U-Boot for one specific board type. This
4338 where "NAME_config" is the name of one of the existing configu-
4339 rations; see boards.cfg for supported names.
4341 Note: for some board special configuration names may exist; check if
4342 additional information is available from the board vendor; for
4343 instance, the TQM823L systems are available without (standard)
4344 or with LCD support. You can select such additional "features"
4345 when choosing the configuration, i. e.
4348 - will configure for a plain TQM823L, i. e. no LCD support
4350 make TQM823L_LCD_config
4351 - will configure for a TQM823L with U-Boot console on LCD
4356 Finally, type "make all", and you should get some working U-Boot
4357 images ready for download to / installation on your system:
4359 - "u-boot.bin" is a raw binary image
4360 - "u-boot" is an image in ELF binary format
4361 - "u-boot.srec" is in Motorola S-Record format
4363 By default the build is performed locally and the objects are saved
4364 in the source directory. One of the two methods can be used to change
4365 this behavior and build U-Boot to some external directory:
4367 1. Add O= to the make command line invocations:
4369 make O=/tmp/build distclean
4370 make O=/tmp/build NAME_config
4371 make O=/tmp/build all
4373 2. Set environment variable BUILD_DIR to point to the desired location:
4375 export BUILD_DIR=/tmp/build
4380 Note that the command line "O=" setting overrides the BUILD_DIR environment
4384 Please be aware that the Makefiles assume you are using GNU make, so
4385 for instance on NetBSD you might need to use "gmake" instead of
4389 If the system board that you have is not listed, then you will need
4390 to port U-Boot to your hardware platform. To do this, follow these
4393 1. Add a new configuration option for your board to the toplevel
4394 "boards.cfg" file, using the existing entries as examples.
4395 Follow the instructions there to keep the boards in order.
4396 2. Create a new directory to hold your board specific code. Add any
4397 files you need. In your board directory, you will need at least
4398 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4399 3. Create a new configuration file "include/configs/<board>.h" for
4401 3. If you're porting U-Boot to a new CPU, then also create a new
4402 directory to hold your CPU specific code. Add any files you need.
4403 4. Run "make <board>_config" with your new name.
4404 5. Type "make", and you should get a working "u-boot.srec" file
4405 to be installed on your target system.
4406 6. Debug and solve any problems that might arise.
4407 [Of course, this last step is much harder than it sounds.]
4410 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4411 ==============================================================
4413 If you have modified U-Boot sources (for instance added a new board
4414 or support for new devices, a new CPU, etc.) you are expected to
4415 provide feedback to the other developers. The feedback normally takes
4416 the form of a "patch", i. e. a context diff against a certain (latest
4417 official or latest in the git repository) version of U-Boot sources.
4419 But before you submit such a patch, please verify that your modifi-
4420 cation did not break existing code. At least make sure that *ALL* of
4421 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4422 just run the "MAKEALL" script, which will configure and build U-Boot
4423 for ALL supported system. Be warned, this will take a while. You can
4424 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4425 environment variable to the script, i. e. to use the ELDK cross tools
4428 CROSS_COMPILE=ppc_8xx- MAKEALL
4430 or to build on a native PowerPC system you can type
4432 CROSS_COMPILE=' ' MAKEALL
4434 When using the MAKEALL script, the default behaviour is to build
4435 U-Boot in the source directory. This location can be changed by
4436 setting the BUILD_DIR environment variable. Also, for each target
4437 built, the MAKEALL script saves two log files (<target>.ERR and
4438 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4439 location can be changed by setting the MAKEALL_LOGDIR environment
4440 variable. For example:
4442 export BUILD_DIR=/tmp/build
4443 export MAKEALL_LOGDIR=/tmp/log
4444 CROSS_COMPILE=ppc_8xx- MAKEALL
4446 With the above settings build objects are saved in the /tmp/build,
4447 log files are saved in the /tmp/log and the source tree remains clean
4448 during the whole build process.
4451 See also "U-Boot Porting Guide" below.
4454 Monitor Commands - Overview:
4455 ============================
4457 go - start application at address 'addr'
4458 run - run commands in an environment variable
4459 bootm - boot application image from memory
4460 bootp - boot image via network using BootP/TFTP protocol
4461 bootz - boot zImage from memory
4462 tftpboot- boot image via network using TFTP protocol
4463 and env variables "ipaddr" and "serverip"
4464 (and eventually "gatewayip")
4465 tftpput - upload a file via network using TFTP protocol
4466 rarpboot- boot image via network using RARP/TFTP protocol
4467 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4468 loads - load S-Record file over serial line
4469 loadb - load binary file over serial line (kermit mode)
4471 mm - memory modify (auto-incrementing)
4472 nm - memory modify (constant address)
4473 mw - memory write (fill)
4475 cmp - memory compare
4476 crc32 - checksum calculation
4477 i2c - I2C sub-system
4478 sspi - SPI utility commands
4479 base - print or set address offset
4480 printenv- print environment variables
4481 setenv - set environment variables
4482 saveenv - save environment variables to persistent storage
4483 protect - enable or disable FLASH write protection
4484 erase - erase FLASH memory
4485 flinfo - print FLASH memory information
4486 nand - NAND memory operations (see doc/README.nand)
4487 bdinfo - print Board Info structure
4488 iminfo - print header information for application image
4489 coninfo - print console devices and informations
4490 ide - IDE sub-system
4491 loop - infinite loop on address range
4492 loopw - infinite write loop on address range
4493 mtest - simple RAM test
4494 icache - enable or disable instruction cache
4495 dcache - enable or disable data cache
4496 reset - Perform RESET of the CPU
4497 echo - echo args to console
4498 version - print monitor version
4499 help - print online help
4500 ? - alias for 'help'
4503 Monitor Commands - Detailed Description:
4504 ========================================
4508 For now: just type "help <command>".
4511 Environment Variables:
4512 ======================
4514 U-Boot supports user configuration using Environment Variables which
4515 can be made persistent by saving to Flash memory.
4517 Environment Variables are set using "setenv", printed using
4518 "printenv", and saved to Flash using "saveenv". Using "setenv"
4519 without a value can be used to delete a variable from the
4520 environment. As long as you don't save the environment you are
4521 working with an in-memory copy. In case the Flash area containing the
4522 environment is erased by accident, a default environment is provided.
4524 Some configuration options can be set using Environment Variables.
4526 List of environment variables (most likely not complete):
4528 baudrate - see CONFIG_BAUDRATE
4530 bootdelay - see CONFIG_BOOTDELAY
4532 bootcmd - see CONFIG_BOOTCOMMAND
4534 bootargs - Boot arguments when booting an RTOS image
4536 bootfile - Name of the image to load with TFTP
4538 bootm_low - Memory range available for image processing in the bootm
4539 command can be restricted. This variable is given as
4540 a hexadecimal number and defines lowest address allowed
4541 for use by the bootm command. See also "bootm_size"
4542 environment variable. Address defined by "bootm_low" is
4543 also the base of the initial memory mapping for the Linux
4544 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4547 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4548 This variable is given as a hexadecimal number and it
4549 defines the size of the memory region starting at base
4550 address bootm_low that is accessible by the Linux kernel
4551 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4552 as the default value if it is defined, and bootm_size is
4555 bootm_size - Memory range available for image processing in the bootm
4556 command can be restricted. This variable is given as
4557 a hexadecimal number and defines the size of the region
4558 allowed for use by the bootm command. See also "bootm_low"
4559 environment variable.
4561 updatefile - Location of the software update file on a TFTP server, used
4562 by the automatic software update feature. Please refer to
4563 documentation in doc/README.update for more details.
4565 autoload - if set to "no" (any string beginning with 'n'),
4566 "bootp" will just load perform a lookup of the
4567 configuration from the BOOTP server, but not try to
4568 load any image using TFTP
4570 autostart - if set to "yes", an image loaded using the "bootp",
4571 "rarpboot", "tftpboot" or "diskboot" commands will
4572 be automatically started (by internally calling
4575 If set to "no", a standalone image passed to the
4576 "bootm" command will be copied to the load address
4577 (and eventually uncompressed), but NOT be started.
4578 This can be used to load and uncompress arbitrary
4581 fdt_high - if set this restricts the maximum address that the
4582 flattened device tree will be copied into upon boot.
4583 For example, if you have a system with 1 GB memory
4584 at physical address 0x10000000, while Linux kernel
4585 only recognizes the first 704 MB as low memory, you
4586 may need to set fdt_high as 0x3C000000 to have the
4587 device tree blob be copied to the maximum address
4588 of the 704 MB low memory, so that Linux kernel can
4589 access it during the boot procedure.
4591 If this is set to the special value 0xFFFFFFFF then
4592 the fdt will not be copied at all on boot. For this
4593 to work it must reside in writable memory, have
4594 sufficient padding on the end of it for u-boot to
4595 add the information it needs into it, and the memory
4596 must be accessible by the kernel.
4598 fdtcontroladdr- if set this is the address of the control flattened
4599 device tree used by U-Boot when CONFIG_OF_CONTROL is
4602 i2cfast - (PPC405GP|PPC405EP only)
4603 if set to 'y' configures Linux I2C driver for fast
4604 mode (400kHZ). This environment variable is used in
4605 initialization code. So, for changes to be effective
4606 it must be saved and board must be reset.
4608 initrd_high - restrict positioning of initrd images:
4609 If this variable is not set, initrd images will be
4610 copied to the highest possible address in RAM; this
4611 is usually what you want since it allows for
4612 maximum initrd size. If for some reason you want to
4613 make sure that the initrd image is loaded below the
4614 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4615 variable to a value of "no" or "off" or "0".
4616 Alternatively, you can set it to a maximum upper
4617 address to use (U-Boot will still check that it
4618 does not overwrite the U-Boot stack and data).
4620 For instance, when you have a system with 16 MB
4621 RAM, and want to reserve 4 MB from use by Linux,
4622 you can do this by adding "mem=12M" to the value of
4623 the "bootargs" variable. However, now you must make
4624 sure that the initrd image is placed in the first
4625 12 MB as well - this can be done with
4627 setenv initrd_high 00c00000
4629 If you set initrd_high to 0xFFFFFFFF, this is an
4630 indication to U-Boot that all addresses are legal
4631 for the Linux kernel, including addresses in flash
4632 memory. In this case U-Boot will NOT COPY the
4633 ramdisk at all. This may be useful to reduce the
4634 boot time on your system, but requires that this
4635 feature is supported by your Linux kernel.
4637 ipaddr - IP address; needed for tftpboot command
4639 loadaddr - Default load address for commands like "bootp",
4640 "rarpboot", "tftpboot", "loadb" or "diskboot"
4642 loads_echo - see CONFIG_LOADS_ECHO
4644 serverip - TFTP server IP address; needed for tftpboot command
4646 bootretry - see CONFIG_BOOT_RETRY_TIME
4648 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4650 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4652 ethprime - controls which interface is used first.
4654 ethact - controls which interface is currently active.
4655 For example you can do the following
4657 => setenv ethact FEC
4658 => ping 192.168.0.1 # traffic sent on FEC
4659 => setenv ethact SCC
4660 => ping 10.0.0.1 # traffic sent on SCC
4662 ethrotate - When set to "no" U-Boot does not go through all
4663 available network interfaces.
4664 It just stays at the currently selected interface.
4666 netretry - When set to "no" each network operation will
4667 either succeed or fail without retrying.
4668 When set to "once" the network operation will
4669 fail when all the available network interfaces
4670 are tried once without success.
4671 Useful on scripts which control the retry operation
4674 npe_ucode - set load address for the NPE microcode
4676 silent_linux - If set then linux will be told to boot silently, by
4677 changing the console to be empty. If "yes" it will be
4678 made silent. If "no" it will not be made silent. If
4679 unset, then it will be made silent if the U-Boot console
4682 tftpsrcport - If this is set, the value is used for TFTP's
4685 tftpdstport - If this is set, the value is used for TFTP's UDP
4686 destination port instead of the Well Know Port 69.
4688 tftpblocksize - Block size to use for TFTP transfers; if not set,
4689 we use the TFTP server's default block size
4691 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4692 seconds, minimum value is 1000 = 1 second). Defines
4693 when a packet is considered to be lost so it has to
4694 be retransmitted. The default is 5000 = 5 seconds.
4695 Lowering this value may make downloads succeed
4696 faster in networks with high packet loss rates or
4697 with unreliable TFTP servers.
4699 vlan - When set to a value < 4095 the traffic over
4700 Ethernet is encapsulated/received over 802.1q
4703 The following image location variables contain the location of images
4704 used in booting. The "Image" column gives the role of the image and is
4705 not an environment variable name. The other columns are environment
4706 variable names. "File Name" gives the name of the file on a TFTP
4707 server, "RAM Address" gives the location in RAM the image will be
4708 loaded to, and "Flash Location" gives the image's address in NOR
4709 flash or offset in NAND flash.
4711 *Note* - these variables don't have to be defined for all boards, some
4712 boards currenlty use other variables for these purposes, and some
4713 boards use these variables for other purposes.
4715 Image File Name RAM Address Flash Location
4716 ----- --------- ----------- --------------
4717 u-boot u-boot u-boot_addr_r u-boot_addr
4718 Linux kernel bootfile kernel_addr_r kernel_addr
4719 device tree blob fdtfile fdt_addr_r fdt_addr
4720 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4722 The following environment variables may be used and automatically
4723 updated by the network boot commands ("bootp" and "rarpboot"),
4724 depending the information provided by your boot server:
4726 bootfile - see above
4727 dnsip - IP address of your Domain Name Server
4728 dnsip2 - IP address of your secondary Domain Name Server
4729 gatewayip - IP address of the Gateway (Router) to use
4730 hostname - Target hostname
4732 netmask - Subnet Mask
4733 rootpath - Pathname of the root filesystem on the NFS server
4734 serverip - see above
4737 There are two special Environment Variables:
4739 serial# - contains hardware identification information such
4740 as type string and/or serial number
4741 ethaddr - Ethernet address
4743 These variables can be set only once (usually during manufacturing of
4744 the board). U-Boot refuses to delete or overwrite these variables
4745 once they have been set once.
4748 Further special Environment Variables:
4750 ver - Contains the U-Boot version string as printed
4751 with the "version" command. This variable is
4752 readonly (see CONFIG_VERSION_VARIABLE).
4755 Please note that changes to some configuration parameters may take
4756 only effect after the next boot (yes, that's just like Windoze :-).
4759 Callback functions for environment variables:
4760 ---------------------------------------------
4762 For some environment variables, the behavior of u-boot needs to change
4763 when their values are changed. This functionailty allows functions to
4764 be associated with arbitrary variables. On creation, overwrite, or
4765 deletion, the callback will provide the opportunity for some side
4766 effect to happen or for the change to be rejected.
4768 The callbacks are named and associated with a function using the
4769 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4771 These callbacks are associated with variables in one of two ways. The
4772 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4773 in the board configuration to a string that defines a list of
4774 associations. The list must be in the following format:
4776 entry = variable_name[:callback_name]
4779 If the callback name is not specified, then the callback is deleted.
4780 Spaces are also allowed anywhere in the list.
4782 Callbacks can also be associated by defining the ".callbacks" variable
4783 with the same list format above. Any association in ".callbacks" will
4784 override any association in the static list. You can define
4785 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4786 ".callbacks" envirnoment variable in the default or embedded environment.
4789 Command Line Parsing:
4790 =====================
4792 There are two different command line parsers available with U-Boot:
4793 the old "simple" one, and the much more powerful "hush" shell:
4795 Old, simple command line parser:
4796 --------------------------------
4798 - supports environment variables (through setenv / saveenv commands)
4799 - several commands on one line, separated by ';'
4800 - variable substitution using "... ${name} ..." syntax
4801 - special characters ('$', ';') can be escaped by prefixing with '\',
4803 setenv bootcmd bootm \${address}
4804 - You can also escape text by enclosing in single apostrophes, for example:
4805 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4810 - similar to Bourne shell, with control structures like
4811 if...then...else...fi, for...do...done; while...do...done,
4812 until...do...done, ...
4813 - supports environment ("global") variables (through setenv / saveenv
4814 commands) and local shell variables (through standard shell syntax
4815 "name=value"); only environment variables can be used with "run"
4821 (1) If a command line (or an environment variable executed by a "run"
4822 command) contains several commands separated by semicolon, and
4823 one of these commands fails, then the remaining commands will be
4826 (2) If you execute several variables with one call to run (i. e.
4827 calling run with a list of variables as arguments), any failing
4828 command will cause "run" to terminate, i. e. the remaining
4829 variables are not executed.
4831 Note for Redundant Ethernet Interfaces:
4832 =======================================
4834 Some boards come with redundant Ethernet interfaces; U-Boot supports
4835 such configurations and is capable of automatic selection of a
4836 "working" interface when needed. MAC assignment works as follows:
4838 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4839 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4840 "eth1addr" (=>eth1), "eth2addr", ...
4842 If the network interface stores some valid MAC address (for instance
4843 in SROM), this is used as default address if there is NO correspon-
4844 ding setting in the environment; if the corresponding environment
4845 variable is set, this overrides the settings in the card; that means:
4847 o If the SROM has a valid MAC address, and there is no address in the
4848 environment, the SROM's address is used.
4850 o If there is no valid address in the SROM, and a definition in the
4851 environment exists, then the value from the environment variable is
4854 o If both the SROM and the environment contain a MAC address, and
4855 both addresses are the same, this MAC address is used.
4857 o If both the SROM and the environment contain a MAC address, and the
4858 addresses differ, the value from the environment is used and a
4861 o If neither SROM nor the environment contain a MAC address, an error
4864 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4865 will be programmed into hardware as part of the initialization process. This
4866 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4867 The naming convention is as follows:
4868 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4873 U-Boot is capable of booting (and performing other auxiliary operations on)
4874 images in two formats:
4876 New uImage format (FIT)
4877 -----------------------
4879 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4880 to Flattened Device Tree). It allows the use of images with multiple
4881 components (several kernels, ramdisks, etc.), with contents protected by
4882 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4888 Old image format is based on binary files which can be basically anything,
4889 preceded by a special header; see the definitions in include/image.h for
4890 details; basically, the header defines the following image properties:
4892 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4893 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4894 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4895 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4897 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4898 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4899 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4900 * Compression Type (uncompressed, gzip, bzip2)
4906 The header is marked by a special Magic Number, and both the header
4907 and the data portions of the image are secured against corruption by
4914 Although U-Boot should support any OS or standalone application
4915 easily, the main focus has always been on Linux during the design of
4918 U-Boot includes many features that so far have been part of some
4919 special "boot loader" code within the Linux kernel. Also, any
4920 "initrd" images to be used are no longer part of one big Linux image;
4921 instead, kernel and "initrd" are separate images. This implementation
4922 serves several purposes:
4924 - the same features can be used for other OS or standalone
4925 applications (for instance: using compressed images to reduce the
4926 Flash memory footprint)
4928 - it becomes much easier to port new Linux kernel versions because
4929 lots of low-level, hardware dependent stuff are done by U-Boot
4931 - the same Linux kernel image can now be used with different "initrd"
4932 images; of course this also means that different kernel images can
4933 be run with the same "initrd". This makes testing easier (you don't
4934 have to build a new "zImage.initrd" Linux image when you just
4935 change a file in your "initrd"). Also, a field-upgrade of the
4936 software is easier now.
4942 Porting Linux to U-Boot based systems:
4943 ---------------------------------------
4945 U-Boot cannot save you from doing all the necessary modifications to
4946 configure the Linux device drivers for use with your target hardware
4947 (no, we don't intend to provide a full virtual machine interface to
4950 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4952 Just make sure your machine specific header file (for instance
4953 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4954 Information structure as we define in include/asm-<arch>/u-boot.h,
4955 and make sure that your definition of IMAP_ADDR uses the same value
4956 as your U-Boot configuration in CONFIG_SYS_IMMR.
4959 Configuring the Linux kernel:
4960 -----------------------------
4962 No specific requirements for U-Boot. Make sure you have some root
4963 device (initial ramdisk, NFS) for your target system.
4966 Building a Linux Image:
4967 -----------------------
4969 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4970 not used. If you use recent kernel source, a new build target
4971 "uImage" will exist which automatically builds an image usable by
4972 U-Boot. Most older kernels also have support for a "pImage" target,
4973 which was introduced for our predecessor project PPCBoot and uses a
4974 100% compatible format.
4983 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4984 encapsulate a compressed Linux kernel image with header information,
4985 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4987 * build a standard "vmlinux" kernel image (in ELF binary format):
4989 * convert the kernel into a raw binary image:
4991 ${CROSS_COMPILE}-objcopy -O binary \
4992 -R .note -R .comment \
4993 -S vmlinux linux.bin
4995 * compress the binary image:
4999 * package compressed binary image for U-Boot:
5001 mkimage -A ppc -O linux -T kernel -C gzip \
5002 -a 0 -e 0 -n "Linux Kernel Image" \
5003 -d linux.bin.gz uImage
5006 The "mkimage" tool can also be used to create ramdisk images for use
5007 with U-Boot, either separated from the Linux kernel image, or
5008 combined into one file. "mkimage" encapsulates the images with a 64
5009 byte header containing information about target architecture,
5010 operating system, image type, compression method, entry points, time
5011 stamp, CRC32 checksums, etc.
5013 "mkimage" can be called in two ways: to verify existing images and
5014 print the header information, or to build new images.
5016 In the first form (with "-l" option) mkimage lists the information
5017 contained in the header of an existing U-Boot image; this includes
5018 checksum verification:
5020 tools/mkimage -l image
5021 -l ==> list image header information
5023 The second form (with "-d" option) is used to build a U-Boot image
5024 from a "data file" which is used as image payload:
5026 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
5027 -n name -d data_file image
5028 -A ==> set architecture to 'arch'
5029 -O ==> set operating system to 'os'
5030 -T ==> set image type to 'type'
5031 -C ==> set compression type 'comp'
5032 -a ==> set load address to 'addr' (hex)
5033 -e ==> set entry point to 'ep' (hex)
5034 -n ==> set image name to 'name'
5035 -d ==> use image data from 'datafile'
5037 Right now, all Linux kernels for PowerPC systems use the same load
5038 address (0x00000000), but the entry point address depends on the
5041 - 2.2.x kernels have the entry point at 0x0000000C,
5042 - 2.3.x and later kernels have the entry point at 0x00000000.
5044 So a typical call to build a U-Boot image would read:
5046 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5047 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
5048 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
5049 > examples/uImage.TQM850L
5050 Image Name: 2.4.4 kernel for TQM850L
5051 Created: Wed Jul 19 02:34:59 2000
5052 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5053 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5054 Load Address: 0x00000000
5055 Entry Point: 0x00000000
5057 To verify the contents of the image (or check for corruption):
5059 -> tools/mkimage -l examples/uImage.TQM850L
5060 Image Name: 2.4.4 kernel for TQM850L
5061 Created: Wed Jul 19 02:34:59 2000
5062 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5063 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
5064 Load Address: 0x00000000
5065 Entry Point: 0x00000000
5067 NOTE: for embedded systems where boot time is critical you can trade
5068 speed for memory and install an UNCOMPRESSED image instead: this
5069 needs more space in Flash, but boots much faster since it does not
5070 need to be uncompressed:
5072 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
5073 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
5074 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
5075 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
5076 > examples/uImage.TQM850L-uncompressed
5077 Image Name: 2.4.4 kernel for TQM850L
5078 Created: Wed Jul 19 02:34:59 2000
5079 Image Type: PowerPC Linux Kernel Image (uncompressed)
5080 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
5081 Load Address: 0x00000000
5082 Entry Point: 0x00000000
5085 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
5086 when your kernel is intended to use an initial ramdisk:
5088 -> tools/mkimage -n 'Simple Ramdisk Image' \
5089 > -A ppc -O linux -T ramdisk -C gzip \
5090 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
5091 Image Name: Simple Ramdisk Image
5092 Created: Wed Jan 12 14:01:50 2000
5093 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5094 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
5095 Load Address: 0x00000000
5096 Entry Point: 0x00000000
5099 Installing a Linux Image:
5100 -------------------------
5102 To downloading a U-Boot image over the serial (console) interface,
5103 you must convert the image to S-Record format:
5105 objcopy -I binary -O srec examples/image examples/image.srec
5107 The 'objcopy' does not understand the information in the U-Boot
5108 image header, so the resulting S-Record file will be relative to
5109 address 0x00000000. To load it to a given address, you need to
5110 specify the target address as 'offset' parameter with the 'loads'
5113 Example: install the image to address 0x40100000 (which on the
5114 TQM8xxL is in the first Flash bank):
5116 => erase 40100000 401FFFFF
5122 ## Ready for S-Record download ...
5123 ~>examples/image.srec
5124 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5126 15989 15990 15991 15992
5127 [file transfer complete]
5129 ## Start Addr = 0x00000000
5132 You can check the success of the download using the 'iminfo' command;
5133 this includes a checksum verification so you can be sure no data
5134 corruption happened:
5138 ## Checking Image at 40100000 ...
5139 Image Name: 2.2.13 for initrd on TQM850L
5140 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5141 Data Size: 335725 Bytes = 327 kB = 0 MB
5142 Load Address: 00000000
5143 Entry Point: 0000000c
5144 Verifying Checksum ... OK
5150 The "bootm" command is used to boot an application that is stored in
5151 memory (RAM or Flash). In case of a Linux kernel image, the contents
5152 of the "bootargs" environment variable is passed to the kernel as
5153 parameters. You can check and modify this variable using the
5154 "printenv" and "setenv" commands:
5157 => printenv bootargs
5158 bootargs=root=/dev/ram
5160 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5162 => printenv bootargs
5163 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5166 ## Booting Linux kernel at 40020000 ...
5167 Image Name: 2.2.13 for NFS on TQM850L
5168 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5169 Data Size: 381681 Bytes = 372 kB = 0 MB
5170 Load Address: 00000000
5171 Entry Point: 0000000c
5172 Verifying Checksum ... OK
5173 Uncompressing Kernel Image ... OK
5174 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
5175 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5176 time_init: decrementer frequency = 187500000/60
5177 Calibrating delay loop... 49.77 BogoMIPS
5178 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5181 If you want to boot a Linux kernel with initial RAM disk, you pass
5182 the memory addresses of both the kernel and the initrd image (PPBCOOT
5183 format!) to the "bootm" command:
5185 => imi 40100000 40200000
5187 ## Checking Image at 40100000 ...
5188 Image Name: 2.2.13 for initrd on TQM850L
5189 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5190 Data Size: 335725 Bytes = 327 kB = 0 MB
5191 Load Address: 00000000
5192 Entry Point: 0000000c
5193 Verifying Checksum ... OK
5195 ## Checking Image at 40200000 ...
5196 Image Name: Simple Ramdisk Image
5197 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5198 Data Size: 566530 Bytes = 553 kB = 0 MB
5199 Load Address: 00000000
5200 Entry Point: 00000000
5201 Verifying Checksum ... OK
5203 => bootm 40100000 40200000
5204 ## Booting Linux kernel at 40100000 ...
5205 Image Name: 2.2.13 for initrd on TQM850L
5206 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5207 Data Size: 335725 Bytes = 327 kB = 0 MB
5208 Load Address: 00000000
5209 Entry Point: 0000000c
5210 Verifying Checksum ... OK
5211 Uncompressing Kernel Image ... OK
5212 ## Loading RAMDisk Image at 40200000 ...
5213 Image Name: Simple Ramdisk Image
5214 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5215 Data Size: 566530 Bytes = 553 kB = 0 MB
5216 Load Address: 00000000
5217 Entry Point: 00000000
5218 Verifying Checksum ... OK
5219 Loading Ramdisk ... OK
5220 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
5221 Boot arguments: root=/dev/ram
5222 time_init: decrementer frequency = 187500000/60
5223 Calibrating delay loop... 49.77 BogoMIPS
5225 RAMDISK: Compressed image found at block 0
5226 VFS: Mounted root (ext2 filesystem).
5230 Boot Linux and pass a flat device tree:
5233 First, U-Boot must be compiled with the appropriate defines. See the section
5234 titled "Linux Kernel Interface" above for a more in depth explanation. The
5235 following is an example of how to start a kernel and pass an updated
5241 oft=oftrees/mpc8540ads.dtb
5242 => tftp $oftaddr $oft
5243 Speed: 1000, full duplex
5245 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5246 Filename 'oftrees/mpc8540ads.dtb'.
5247 Load address: 0x300000
5250 Bytes transferred = 4106 (100a hex)
5251 => tftp $loadaddr $bootfile
5252 Speed: 1000, full duplex
5254 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5256 Load address: 0x200000
5257 Loading:############
5259 Bytes transferred = 1029407 (fb51f hex)
5264 => bootm $loadaddr - $oftaddr
5265 ## Booting image at 00200000 ...
5266 Image Name: Linux-2.6.17-dirty
5267 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5268 Data Size: 1029343 Bytes = 1005.2 kB
5269 Load Address: 00000000
5270 Entry Point: 00000000
5271 Verifying Checksum ... OK
5272 Uncompressing Kernel Image ... OK
5273 Booting using flat device tree at 0x300000
5274 Using MPC85xx ADS machine description
5275 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5279 More About U-Boot Image Types:
5280 ------------------------------
5282 U-Boot supports the following image types:
5284 "Standalone Programs" are directly runnable in the environment
5285 provided by U-Boot; it is expected that (if they behave
5286 well) you can continue to work in U-Boot after return from
5287 the Standalone Program.
5288 "OS Kernel Images" are usually images of some Embedded OS which
5289 will take over control completely. Usually these programs
5290 will install their own set of exception handlers, device
5291 drivers, set up the MMU, etc. - this means, that you cannot
5292 expect to re-enter U-Boot except by resetting the CPU.
5293 "RAMDisk Images" are more or less just data blocks, and their
5294 parameters (address, size) are passed to an OS kernel that is
5296 "Multi-File Images" contain several images, typically an OS
5297 (Linux) kernel image and one or more data images like
5298 RAMDisks. This construct is useful for instance when you want
5299 to boot over the network using BOOTP etc., where the boot
5300 server provides just a single image file, but you want to get
5301 for instance an OS kernel and a RAMDisk image.
5303 "Multi-File Images" start with a list of image sizes, each
5304 image size (in bytes) specified by an "uint32_t" in network
5305 byte order. This list is terminated by an "(uint32_t)0".
5306 Immediately after the terminating 0 follow the images, one by
5307 one, all aligned on "uint32_t" boundaries (size rounded up to
5308 a multiple of 4 bytes).
5310 "Firmware Images" are binary images containing firmware (like
5311 U-Boot or FPGA images) which usually will be programmed to
5314 "Script files" are command sequences that will be executed by
5315 U-Boot's command interpreter; this feature is especially
5316 useful when you configure U-Boot to use a real shell (hush)
5317 as command interpreter.
5319 Booting the Linux zImage:
5320 -------------------------
5322 On some platforms, it's possible to boot Linux zImage. This is done
5323 using the "bootz" command. The syntax of "bootz" command is the same
5324 as the syntax of "bootm" command.
5326 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5327 kernel with raw initrd images. The syntax is slightly different, the
5328 address of the initrd must be augmented by it's size, in the following
5329 format: "<initrd addres>:<initrd size>".
5335 One of the features of U-Boot is that you can dynamically load and
5336 run "standalone" applications, which can use some resources of
5337 U-Boot like console I/O functions or interrupt services.
5339 Two simple examples are included with the sources:
5344 'examples/hello_world.c' contains a small "Hello World" Demo
5345 application; it is automatically compiled when you build U-Boot.
5346 It's configured to run at address 0x00040004, so you can play with it
5350 ## Ready for S-Record download ...
5351 ~>examples/hello_world.srec
5352 1 2 3 4 5 6 7 8 9 10 11 ...
5353 [file transfer complete]
5355 ## Start Addr = 0x00040004
5357 => go 40004 Hello World! This is a test.
5358 ## Starting application at 0x00040004 ...
5369 Hit any key to exit ...
5371 ## Application terminated, rc = 0x0
5373 Another example, which demonstrates how to register a CPM interrupt
5374 handler with the U-Boot code, can be found in 'examples/timer.c'.
5375 Here, a CPM timer is set up to generate an interrupt every second.
5376 The interrupt service routine is trivial, just printing a '.'
5377 character, but this is just a demo program. The application can be
5378 controlled by the following keys:
5380 ? - print current values og the CPM Timer registers
5381 b - enable interrupts and start timer
5382 e - stop timer and disable interrupts
5383 q - quit application
5386 ## Ready for S-Record download ...
5387 ~>examples/timer.srec
5388 1 2 3 4 5 6 7 8 9 10 11 ...
5389 [file transfer complete]
5391 ## Start Addr = 0x00040004
5394 ## Starting application at 0x00040004 ...
5397 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5400 [q, b, e, ?] Set interval 1000000 us
5403 [q, b, e, ?] ........
5404 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5407 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5410 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5413 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5415 [q, b, e, ?] ...Stopping timer
5417 [q, b, e, ?] ## Application terminated, rc = 0x0
5423 Over time, many people have reported problems when trying to use the
5424 "minicom" terminal emulation program for serial download. I (wd)
5425 consider minicom to be broken, and recommend not to use it. Under
5426 Unix, I recommend to use C-Kermit for general purpose use (and
5427 especially for kermit binary protocol download ("loadb" command), and
5428 use "cu" for S-Record download ("loads" command). See
5429 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5430 for help with kermit.
5433 Nevertheless, if you absolutely want to use it try adding this
5434 configuration to your "File transfer protocols" section:
5436 Name Program Name U/D FullScr IO-Red. Multi
5437 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5438 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5444 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5445 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5447 Building requires a cross environment; it is known to work on
5448 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5449 need gmake since the Makefiles are not compatible with BSD make).
5450 Note that the cross-powerpc package does not install include files;
5451 attempting to build U-Boot will fail because <machine/ansi.h> is
5452 missing. This file has to be installed and patched manually:
5454 # cd /usr/pkg/cross/powerpc-netbsd/include
5456 # ln -s powerpc machine
5457 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5458 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5460 Native builds *don't* work due to incompatibilities between native
5461 and U-Boot include files.
5463 Booting assumes that (the first part of) the image booted is a
5464 stage-2 loader which in turn loads and then invokes the kernel
5465 proper. Loader sources will eventually appear in the NetBSD source
5466 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5467 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5470 Implementation Internals:
5471 =========================
5473 The following is not intended to be a complete description of every
5474 implementation detail. However, it should help to understand the
5475 inner workings of U-Boot and make it easier to port it to custom
5479 Initial Stack, Global Data:
5480 ---------------------------
5482 The implementation of U-Boot is complicated by the fact that U-Boot
5483 starts running out of ROM (flash memory), usually without access to
5484 system RAM (because the memory controller is not initialized yet).
5485 This means that we don't have writable Data or BSS segments, and BSS
5486 is not initialized as zero. To be able to get a C environment working
5487 at all, we have to allocate at least a minimal stack. Implementation
5488 options for this are defined and restricted by the CPU used: Some CPU
5489 models provide on-chip memory (like the IMMR area on MPC8xx and
5490 MPC826x processors), on others (parts of) the data cache can be
5491 locked as (mis-) used as memory, etc.
5493 Chris Hallinan posted a good summary of these issues to the
5494 U-Boot mailing list:
5496 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5497 From: "Chris Hallinan" <clh@net1plus.com>
5498 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5501 Correct me if I'm wrong, folks, but the way I understand it
5502 is this: Using DCACHE as initial RAM for Stack, etc, does not
5503 require any physical RAM backing up the cache. The cleverness
5504 is that the cache is being used as a temporary supply of
5505 necessary storage before the SDRAM controller is setup. It's
5506 beyond the scope of this list to explain the details, but you
5507 can see how this works by studying the cache architecture and
5508 operation in the architecture and processor-specific manuals.
5510 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5511 is another option for the system designer to use as an
5512 initial stack/RAM area prior to SDRAM being available. Either
5513 option should work for you. Using CS 4 should be fine if your
5514 board designers haven't used it for something that would
5515 cause you grief during the initial boot! It is frequently not
5518 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5519 with your processor/board/system design. The default value
5520 you will find in any recent u-boot distribution in
5521 walnut.h should work for you. I'd set it to a value larger
5522 than your SDRAM module. If you have a 64MB SDRAM module, set
5523 it above 400_0000. Just make sure your board has no resources
5524 that are supposed to respond to that address! That code in
5525 start.S has been around a while and should work as is when
5526 you get the config right.
5531 It is essential to remember this, since it has some impact on the C
5532 code for the initialization procedures:
5534 * Initialized global data (data segment) is read-only. Do not attempt
5537 * Do not use any uninitialized global data (or implicitely initialized
5538 as zero data - BSS segment) at all - this is undefined, initiali-
5539 zation is performed later (when relocating to RAM).
5541 * Stack space is very limited. Avoid big data buffers or things like
5544 Having only the stack as writable memory limits means we cannot use
5545 normal global data to share information beween the code. But it
5546 turned out that the implementation of U-Boot can be greatly
5547 simplified by making a global data structure (gd_t) available to all
5548 functions. We could pass a pointer to this data as argument to _all_
5549 functions, but this would bloat the code. Instead we use a feature of
5550 the GCC compiler (Global Register Variables) to share the data: we
5551 place a pointer (gd) to the global data into a register which we
5552 reserve for this purpose.
5554 When choosing a register for such a purpose we are restricted by the
5555 relevant (E)ABI specifications for the current architecture, and by
5556 GCC's implementation.
5558 For PowerPC, the following registers have specific use:
5560 R2: reserved for system use
5561 R3-R4: parameter passing and return values
5562 R5-R10: parameter passing
5563 R13: small data area pointer
5567 (U-Boot also uses R12 as internal GOT pointer. r12
5568 is a volatile register so r12 needs to be reset when
5569 going back and forth between asm and C)
5571 ==> U-Boot will use R2 to hold a pointer to the global data
5573 Note: on PPC, we could use a static initializer (since the
5574 address of the global data structure is known at compile time),
5575 but it turned out that reserving a register results in somewhat
5576 smaller code - although the code savings are not that big (on
5577 average for all boards 752 bytes for the whole U-Boot image,
5578 624 text + 127 data).
5580 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5581 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5583 ==> U-Boot will use P3 to hold a pointer to the global data
5585 On ARM, the following registers are used:
5587 R0: function argument word/integer result
5588 R1-R3: function argument word
5589 R9: platform specific
5590 R10: stack limit (used only if stack checking is enabled)
5591 R11: argument (frame) pointer
5592 R12: temporary workspace
5595 R15: program counter
5597 ==> U-Boot will use R9 to hold a pointer to the global data
5599 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
5601 On Nios II, the ABI is documented here:
5602 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5604 ==> U-Boot will use gp to hold a pointer to the global data
5606 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5607 to access small data sections, so gp is free.
5609 On NDS32, the following registers are used:
5611 R0-R1: argument/return
5613 R15: temporary register for assembler
5614 R16: trampoline register
5615 R28: frame pointer (FP)
5616 R29: global pointer (GP)
5617 R30: link register (LP)
5618 R31: stack pointer (SP)
5619 PC: program counter (PC)
5621 ==> U-Boot will use R10 to hold a pointer to the global data
5623 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5624 or current versions of GCC may "optimize" the code too much.
5629 U-Boot runs in system state and uses physical addresses, i.e. the
5630 MMU is not used either for address mapping nor for memory protection.
5632 The available memory is mapped to fixed addresses using the memory
5633 controller. In this process, a contiguous block is formed for each
5634 memory type (Flash, SDRAM, SRAM), even when it consists of several
5635 physical memory banks.
5637 U-Boot is installed in the first 128 kB of the first Flash bank (on
5638 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5639 booting and sizing and initializing DRAM, the code relocates itself
5640 to the upper end of DRAM. Immediately below the U-Boot code some
5641 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5642 configuration setting]. Below that, a structure with global Board
5643 Info data is placed, followed by the stack (growing downward).
5645 Additionally, some exception handler code is copied to the low 8 kB
5646 of DRAM (0x00000000 ... 0x00001FFF).
5648 So a typical memory configuration with 16 MB of DRAM could look like
5651 0x0000 0000 Exception Vector code
5654 0x0000 2000 Free for Application Use
5660 0x00FB FF20 Monitor Stack (Growing downward)
5661 0x00FB FFAC Board Info Data and permanent copy of global data
5662 0x00FC 0000 Malloc Arena
5665 0x00FE 0000 RAM Copy of Monitor Code
5666 ... eventually: LCD or video framebuffer
5667 ... eventually: pRAM (Protected RAM - unchanged by reset)
5668 0x00FF FFFF [End of RAM]
5671 System Initialization:
5672 ----------------------
5674 In the reset configuration, U-Boot starts at the reset entry point
5675 (on most PowerPC systems at address 0x00000100). Because of the reset
5676 configuration for CS0# this is a mirror of the onboard Flash memory.
5677 To be able to re-map memory U-Boot then jumps to its link address.
5678 To be able to implement the initialization code in C, a (small!)
5679 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5680 which provide such a feature like MPC8xx or MPC8260), or in a locked
5681 part of the data cache. After that, U-Boot initializes the CPU core,
5682 the caches and the SIU.
5684 Next, all (potentially) available memory banks are mapped using a
5685 preliminary mapping. For example, we put them on 512 MB boundaries
5686 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5687 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5688 programmed for SDRAM access. Using the temporary configuration, a
5689 simple memory test is run that determines the size of the SDRAM
5692 When there is more than one SDRAM bank, and the banks are of
5693 different size, the largest is mapped first. For equal size, the first
5694 bank (CS2#) is mapped first. The first mapping is always for address
5695 0x00000000, with any additional banks following immediately to create
5696 contiguous memory starting from 0.
5698 Then, the monitor installs itself at the upper end of the SDRAM area
5699 and allocates memory for use by malloc() and for the global Board
5700 Info data; also, the exception vector code is copied to the low RAM
5701 pages, and the final stack is set up.
5703 Only after this relocation will you have a "normal" C environment;
5704 until that you are restricted in several ways, mostly because you are
5705 running from ROM, and because the code will have to be relocated to a
5709 U-Boot Porting Guide:
5710 ----------------------
5712 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5716 int main(int argc, char *argv[])
5718 sighandler_t no_more_time;
5720 signal(SIGALRM, no_more_time);
5721 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5723 if (available_money > available_manpower) {
5724 Pay consultant to port U-Boot;
5728 Download latest U-Boot source;
5730 Subscribe to u-boot mailing list;
5733 email("Hi, I am new to U-Boot, how do I get started?");
5736 Read the README file in the top level directory;
5737 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5738 Read applicable doc/*.README;
5739 Read the source, Luke;
5740 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5743 if (available_money > toLocalCurrency ($2500))
5746 Add a lot of aggravation and time;
5748 if (a similar board exists) { /* hopefully... */
5749 cp -a board/<similar> board/<myboard>
5750 cp include/configs/<similar>.h include/configs/<myboard>.h
5752 Create your own board support subdirectory;
5753 Create your own board include/configs/<myboard>.h file;
5755 Edit new board/<myboard> files
5756 Edit new include/configs/<myboard>.h
5761 Add / modify source code;
5765 email("Hi, I am having problems...");
5767 Send patch file to the U-Boot email list;
5768 if (reasonable critiques)
5769 Incorporate improvements from email list code review;
5771 Defend code as written;
5777 void no_more_time (int sig)
5786 All contributions to U-Boot should conform to the Linux kernel
5787 coding style; see the file "Documentation/CodingStyle" and the script
5788 "scripts/Lindent" in your Linux kernel source directory.
5790 Source files originating from a different project (for example the
5791 MTD subsystem) are generally exempt from these guidelines and are not
5792 reformated to ease subsequent migration to newer versions of those
5795 Please note that U-Boot is implemented in C (and to some small parts in
5796 Assembler); no C++ is used, so please do not use C++ style comments (//)
5799 Please also stick to the following formatting rules:
5800 - remove any trailing white space
5801 - use TAB characters for indentation and vertical alignment, not spaces
5802 - make sure NOT to use DOS '\r\n' line feeds
5803 - do not add more than 2 consecutive empty lines to source files
5804 - do not add trailing empty lines to source files
5806 Submissions which do not conform to the standards may be returned
5807 with a request to reformat the changes.
5813 Since the number of patches for U-Boot is growing, we need to
5814 establish some rules. Submissions which do not conform to these rules
5815 may be rejected, even when they contain important and valuable stuff.
5817 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5819 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5820 see http://lists.denx.de/mailman/listinfo/u-boot
5822 When you send a patch, please include the following information with
5825 * For bug fixes: a description of the bug and how your patch fixes
5826 this bug. Please try to include a way of demonstrating that the
5827 patch actually fixes something.
5829 * For new features: a description of the feature and your
5832 * A CHANGELOG entry as plaintext (separate from the patch)
5834 * For major contributions, your entry to the CREDITS file
5836 * When you add support for a new board, don't forget to add a
5837 maintainer e-mail address to the boards.cfg file, too.
5839 * If your patch adds new configuration options, don't forget to
5840 document these in the README file.
5842 * The patch itself. If you are using git (which is *strongly*
5843 recommended) you can easily generate the patch using the
5844 "git format-patch". If you then use "git send-email" to send it to
5845 the U-Boot mailing list, you will avoid most of the common problems
5846 with some other mail clients.
5848 If you cannot use git, use "diff -purN OLD NEW". If your version of
5849 diff does not support these options, then get the latest version of
5852 The current directory when running this command shall be the parent
5853 directory of the U-Boot source tree (i. e. please make sure that
5854 your patch includes sufficient directory information for the
5857 We prefer patches as plain text. MIME attachments are discouraged,
5858 and compressed attachments must not be used.
5860 * If one logical set of modifications affects or creates several
5861 files, all these changes shall be submitted in a SINGLE patch file.
5863 * Changesets that contain different, unrelated modifications shall be
5864 submitted as SEPARATE patches, one patch per changeset.
5869 * Before sending the patch, run the MAKEALL script on your patched
5870 source tree and make sure that no errors or warnings are reported
5871 for any of the boards.
5873 * Keep your modifications to the necessary minimum: A patch
5874 containing several unrelated changes or arbitrary reformats will be
5875 returned with a request to re-formatting / split it.
5877 * If you modify existing code, make sure that your new code does not
5878 add to the memory footprint of the code ;-) Small is beautiful!
5879 When adding new features, these should compile conditionally only
5880 (using #ifdef), and the resulting code with the new feature
5881 disabled must not need more memory than the old code without your
5884 * Remember that there is a size limit of 100 kB per message on the
5885 u-boot mailing list. Bigger patches will be moderated. If they are
5886 reasonable and not too big, they will be acknowledged. But patches
5887 bigger than the size limit should be avoided.