2 # (C) Copyright 2000 - 2012
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
57 Note: There is no CHANGELOG file in the actual U-Boot source tree;
58 it can be created dynamically from the Git log using:
66 In case you have questions about, problems with or contributions for
67 U-Boot you should send a message to the U-Boot mailing list at
68 <u-boot@lists.denx.de>. There is also an archive of previous traffic
69 on the mailing list - please search the archive before asking FAQ's.
70 Please see http://lists.denx.de/pipermail/u-boot and
71 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
74 Where to get source code:
75 =========================
77 The U-Boot source code is maintained in the git repository at
78 git://www.denx.de/git/u-boot.git ; you can browse it online at
79 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
81 The "snapshot" links on this page allow you to download tarballs of
82 any version you might be interested in. Official releases are also
83 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
86 Pre-built (and tested) images are available from
87 ftp://ftp.denx.de/pub/u-boot/images/
93 - start from 8xxrom sources
94 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
96 - make it easier to add custom boards
97 - make it possible to add other [PowerPC] CPUs
98 - extend functions, especially:
99 * Provide extended interface to Linux boot loader
102 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
103 - create ARMBoot project (http://sourceforge.net/projects/armboot)
104 - add other CPU families (starting with ARM)
105 - create U-Boot project (http://sourceforge.net/projects/u-boot)
106 - current project page: see http://www.denx.de/wiki/U-Boot
112 The "official" name of this project is "Das U-Boot". The spelling
113 "U-Boot" shall be used in all written text (documentation, comments
114 in source files etc.). Example:
116 This is the README file for the U-Boot project.
118 File names etc. shall be based on the string "u-boot". Examples:
120 include/asm-ppc/u-boot.h
122 #include <asm/u-boot.h>
124 Variable names, preprocessor constants etc. shall be either based on
125 the string "u_boot" or on "U_BOOT". Example:
127 U_BOOT_VERSION u_boot_logo
128 IH_OS_U_BOOT u_boot_hush_start
134 Starting with the release in October 2008, the names of the releases
135 were changed from numerical release numbers without deeper meaning
136 into a time stamp based numbering. Regular releases are identified by
137 names consisting of the calendar year and month of the release date.
138 Additional fields (if present) indicate release candidates or bug fix
139 releases in "stable" maintenance trees.
142 U-Boot v2009.11 - Release November 2009
143 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
144 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
150 /arch Architecture specific files
151 /arm Files generic to ARM architecture
152 /cpu CPU specific files
153 /arm720t Files specific to ARM 720 CPUs
154 /arm920t Files specific to ARM 920 CPUs
155 /at91 Files specific to Atmel AT91RM9200 CPU
156 /imx Files specific to Freescale MC9328 i.MX CPUs
157 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
158 /arm925t Files specific to ARM 925 CPUs
159 /arm926ejs Files specific to ARM 926 CPUs
160 /arm1136 Files specific to ARM 1136 CPUs
161 /ixp Files specific to Intel XScale IXP CPUs
162 /pxa Files specific to Intel XScale PXA CPUs
163 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
164 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
165 /lib Architecture specific library files
166 /avr32 Files generic to AVR32 architecture
167 /cpu CPU specific files
168 /lib Architecture specific library files
169 /blackfin Files generic to Analog Devices Blackfin architecture
170 /cpu CPU specific files
171 /lib Architecture specific library files
172 /x86 Files generic to x86 architecture
173 /cpu CPU specific files
174 /lib Architecture specific library files
175 /m68k Files generic to m68k architecture
176 /cpu CPU specific files
177 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
178 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
179 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
180 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
181 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
182 /lib Architecture specific library files
183 /microblaze Files generic to microblaze architecture
184 /cpu CPU specific files
185 /lib Architecture specific library files
186 /mips Files generic to MIPS architecture
187 /cpu CPU specific files
188 /mips32 Files specific to MIPS32 CPUs
189 /xburst Files specific to Ingenic XBurst CPUs
190 /lib Architecture specific library files
191 /nds32 Files generic to NDS32 architecture
192 /cpu CPU specific files
193 /n1213 Files specific to Andes Technology N1213 CPUs
194 /lib Architecture specific library files
195 /nios2 Files generic to Altera NIOS2 architecture
196 /cpu CPU specific files
197 /lib Architecture specific library files
198 /powerpc Files generic to PowerPC architecture
199 /cpu CPU specific files
200 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
201 /mpc5xx Files specific to Freescale MPC5xx CPUs
202 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
203 /mpc8xx Files specific to Freescale MPC8xx CPUs
204 /mpc824x Files specific to Freescale MPC824x CPUs
205 /mpc8260 Files specific to Freescale MPC8260 CPUs
206 /mpc85xx Files specific to Freescale MPC85xx CPUs
207 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
208 /lib Architecture specific library files
209 /sh Files generic to SH architecture
210 /cpu CPU specific files
211 /sh2 Files specific to sh2 CPUs
212 /sh3 Files specific to sh3 CPUs
213 /sh4 Files specific to sh4 CPUs
214 /lib Architecture specific library files
215 /sparc Files generic to SPARC architecture
216 /cpu CPU specific files
217 /leon2 Files specific to Gaisler LEON2 SPARC CPU
218 /leon3 Files specific to Gaisler LEON3 SPARC CPU
219 /lib Architecture specific library files
220 /api Machine/arch independent API for external apps
221 /board Board dependent files
222 /common Misc architecture independent functions
223 /disk Code for disk drive partition handling
224 /doc Documentation (don't expect too much)
225 /drivers Commonly used device drivers
226 /examples Example code for standalone applications, etc.
227 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
228 /include Header Files
229 /lib Files generic to all architectures
230 /libfdt Library files to support flattened device trees
231 /lzma Library files to support LZMA decompression
232 /lzo Library files to support LZO decompression
234 /post Power On Self Test
235 /rtc Real Time Clock drivers
236 /tools Tools to build S-Record or U-Boot images, etc.
238 Software Configuration:
239 =======================
241 Configuration is usually done using C preprocessor defines; the
242 rationale behind that is to avoid dead code whenever possible.
244 There are two classes of configuration variables:
246 * Configuration _OPTIONS_:
247 These are selectable by the user and have names beginning with
250 * Configuration _SETTINGS_:
251 These depend on the hardware etc. and should not be meddled with if
252 you don't know what you're doing; they have names beginning with
255 Later we will add a configuration tool - probably similar to or even
256 identical to what's used for the Linux kernel. Right now, we have to
257 do the configuration by hand, which means creating some symbolic
258 links and editing some configuration files. We use the TQM8xxL boards
262 Selection of Processor Architecture and Board Type:
263 ---------------------------------------------------
265 For all supported boards there are ready-to-use default
266 configurations available; just type "make <board_name>_config".
268 Example: For a TQM823L module type:
273 For the Cogent platform, you need to specify the CPU type as well;
274 e.g. "make cogent_mpc8xx_config". And also configure the cogent
275 directory according to the instructions in cogent/README.
278 Configuration Options:
279 ----------------------
281 Configuration depends on the combination of board and CPU type; all
282 such information is kept in a configuration file
283 "include/configs/<board_name>.h".
285 Example: For a TQM823L module, all configuration settings are in
286 "include/configs/TQM823L.h".
289 Many of the options are named exactly as the corresponding Linux
290 kernel configuration options. The intention is to make it easier to
291 build a config tool - later.
294 The following options need to be configured:
296 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
298 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
300 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
301 Define exactly one, e.g. CONFIG_ATSTK1002
303 - CPU Module Type: (if CONFIG_COGENT is defined)
304 Define exactly one of
306 --- FIXME --- not tested yet:
307 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
308 CONFIG_CMA287_23, CONFIG_CMA287_50
310 - Motherboard Type: (if CONFIG_COGENT is defined)
311 Define exactly one of
312 CONFIG_CMA101, CONFIG_CMA102
314 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
315 Define one or more of
318 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
319 Define one or more of
320 CONFIG_LCD_HEARTBEAT - update a character position on
321 the LCD display every second with
324 - Board flavour: (if CONFIG_MPC8260ADS is defined)
327 CONFIG_SYS_8260ADS - original MPC8260ADS
328 CONFIG_SYS_8266ADS - MPC8266ADS
329 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
330 CONFIG_SYS_8272ADS - MPC8272ADS
332 - Marvell Family Member
333 CONFIG_SYS_MVFS - define it if you want to enable
334 multiple fs option at one time
335 for marvell soc family
337 - MPC824X Family Member (if CONFIG_MPC824X is defined)
338 Define exactly one of
339 CONFIG_MPC8240, CONFIG_MPC8245
341 - 8xx CPU Options: (if using an MPC8xx CPU)
342 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
343 get_gclk_freq() cannot work
344 e.g. if there is no 32KHz
345 reference PIT/RTC clock
346 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
349 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
350 CONFIG_SYS_8xx_CPUCLK_MIN
351 CONFIG_SYS_8xx_CPUCLK_MAX
352 CONFIG_8xx_CPUCLK_DEFAULT
353 See doc/README.MPC866
355 CONFIG_SYS_MEASURE_CPUCLK
357 Define this to measure the actual CPU clock instead
358 of relying on the correctness of the configured
359 values. Mostly useful for board bringup to make sure
360 the PLL is locked at the intended frequency. Note
361 that this requires a (stable) reference clock (32 kHz
362 RTC clock or CONFIG_SYS_8XX_XIN)
364 CONFIG_SYS_DELAYED_ICACHE
366 Define this option if you want to enable the
367 ICache only when Code runs from RAM.
372 Specifies that the core is a 64-bit PowerPC implementation (implements
373 the "64" category of the Power ISA). This is necessary for ePAPR
374 compliance, among other possible reasons.
376 CONFIG_SYS_FSL_TBCLK_DIV
378 Defines the core time base clock divider ratio compared to the
379 system clock. On most PQ3 devices this is 8, on newer QorIQ
380 devices it can be 16 or 32. The ratio varies from SoC to Soc.
382 CONFIG_SYS_FSL_PCIE_COMPAT
384 Defines the string to utilize when trying to match PCIe device
385 tree nodes for the given platform.
387 CONFIG_SYS_PPC_E500_DEBUG_TLB
389 Enables a temporary TLB entry to be used during boot to work
390 around limitations in e500v1 and e500v2 external debugger
391 support. This reduces the portions of the boot code where
392 breakpoints and single stepping do not work. The value of this
393 symbol should be set to the TLB1 entry to be used for this
396 CONFIG_SYS_FSL_ERRATUM_A004510
398 Enables a workaround for erratum A004510. If set,
399 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
400 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
402 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
405 Defines one or two SoC revisions (low 8 bits of SVR)
406 for which the A004510 workaround should be applied.
408 The rest of SVR is either not relevant to the decision
409 of whether the erratum is present (e.g. p2040 versus
410 p2041) or is implied by the build target, which controls
411 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
413 See Freescale App Note 4493 for more information about
416 CONFIG_A003399_NOR_WORKAROUND
417 Enables a workaround for IFC erratum A003399. It is only
418 requred during NOR boot.
420 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
422 This is the value to write into CCSR offset 0x18600
423 according to the A004510 workaround.
425 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
426 This value denotes start offset of M2 memory
427 which is directly connected to the DSP core.
429 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
430 This value denotes start offset of DSP CCSR space.
432 - Generic CPU options:
433 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
435 Defines the endianess of the CPU. Implementation of those
436 values is arch specific.
438 - Intel Monahans options:
439 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
441 Defines the Monahans run mode to oscillator
442 ratio. Valid values are 8, 16, 24, 31. The core
443 frequency is this value multiplied by 13 MHz.
445 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
447 Defines the Monahans turbo mode to oscillator
448 ratio. Valid values are 1 (default if undefined) and
449 2. The core frequency as calculated above is multiplied
453 CONFIG_SYS_INIT_SP_OFFSET
455 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
456 pointer. This is needed for the temporary stack before
459 CONFIG_SYS_MIPS_CACHE_MODE
461 Cache operation mode for the MIPS CPU.
462 See also arch/mips/include/asm/mipsregs.h.
464 CONF_CM_CACHABLE_NO_WA
467 CONF_CM_CACHABLE_NONCOHERENT
471 CONF_CM_CACHABLE_ACCELERATED
473 CONFIG_SYS_XWAY_EBU_BOOTCFG
475 Special option for Lantiq XWAY SoCs for booting from NOR flash.
476 See also arch/mips/cpu/mips32/start.S.
478 CONFIG_XWAY_SWAP_BYTES
480 Enable compilation of tools/xway-swap-bytes needed for Lantiq
481 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
482 be swapped if a flash programmer is used.
485 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
487 Select high exception vectors of the ARM core, e.g., do not
488 clear the V bit of the c1 register of CP15.
490 CONFIG_SYS_THUMB_BUILD
492 Use this flag to build U-Boot using the Thumb instruction
493 set for ARM architectures. Thumb instruction set provides
494 better code density. For ARM architectures that support
495 Thumb2 this flag will result in Thumb2 code generated by
498 CONFIG_ARM_ERRATA_716044
499 CONFIG_ARM_ERRATA_742230
500 CONFIG_ARM_ERRATA_743622
501 CONFIG_ARM_ERRATA_751472
503 If set, the workarounds for these ARM errata are applied early
504 during U-Boot startup. Note that these options force the
505 workarounds to be applied; no CPU-type/version detection
506 exists, unlike the similar options in the Linux kernel. Do not
507 set these options unless they apply!
512 The frequency of the timer returned by get_timer().
513 get_timer() must operate in milliseconds and this CONFIG
514 option must be set to 1000.
516 - Linux Kernel Interface:
519 U-Boot stores all clock information in Hz
520 internally. For binary compatibility with older Linux
521 kernels (which expect the clocks passed in the
522 bd_info data to be in MHz) the environment variable
523 "clocks_in_mhz" can be defined so that U-Boot
524 converts clock data to MHZ before passing it to the
526 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
527 "clocks_in_mhz=1" is automatically included in the
530 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
532 When transferring memsize parameter to linux, some versions
533 expect it to be in bytes, others in MB.
534 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
538 New kernel versions are expecting firmware settings to be
539 passed using flattened device trees (based on open firmware
543 * New libfdt-based support
544 * Adds the "fdt" command
545 * The bootm command automatically updates the fdt
547 OF_CPU - The proper name of the cpus node (only required for
548 MPC512X and MPC5xxx based boards).
549 OF_SOC - The proper name of the soc node (only required for
550 MPC512X and MPC5xxx based boards).
551 OF_TBCLK - The timebase frequency.
552 OF_STDOUT_PATH - The path to the console device
554 boards with QUICC Engines require OF_QE to set UCC MAC
557 CONFIG_OF_BOARD_SETUP
559 Board code has addition modification that it wants to make
560 to the flat device tree before handing it off to the kernel
564 This define fills in the correct boot CPU in the boot
565 param header, the default value is zero if undefined.
569 U-Boot can detect if an IDE device is present or not.
570 If not, and this new config option is activated, U-Boot
571 removes the ATA node from the DTS before booting Linux,
572 so the Linux IDE driver does not probe the device and
573 crash. This is needed for buggy hardware (uc101) where
574 no pull down resistor is connected to the signal IDE5V_DD7.
576 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
578 This setting is mandatory for all boards that have only one
579 machine type and must be used to specify the machine type
580 number as it appears in the ARM machine registry
581 (see http://www.arm.linux.org.uk/developer/machines/).
582 Only boards that have multiple machine types supported
583 in a single configuration file and the machine type is
584 runtime discoverable, do not have to use this setting.
586 - vxWorks boot parameters:
588 bootvx constructs a valid bootline using the following
589 environments variables: bootfile, ipaddr, serverip, hostname.
590 It loads the vxWorks image pointed bootfile.
592 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
593 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
594 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
595 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
597 CONFIG_SYS_VXWORKS_ADD_PARAMS
599 Add it at the end of the bootline. E.g "u=username pw=secret"
601 Note: If a "bootargs" environment is defined, it will overwride
602 the defaults discussed just above.
604 - Cache Configuration:
605 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
606 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
607 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
609 - Cache Configuration for ARM:
610 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
612 CONFIG_SYS_PL310_BASE - Physical base address of PL310
613 controller register space
618 Define this if you want support for Amba PrimeCell PL010 UARTs.
622 Define this if you want support for Amba PrimeCell PL011 UARTs.
626 If you have Amba PrimeCell PL011 UARTs, set this variable to
627 the clock speed of the UARTs.
631 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
632 define this to a list of base addresses for each (supported)
633 port. See e.g. include/configs/versatile.h
635 CONFIG_PL011_SERIAL_RLCR
637 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
638 have separate receive and transmit line control registers. Set
639 this variable to initialize the extra register.
641 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
643 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
644 boot loader that has already initialized the UART. Define this
645 variable to flush the UART at init time.
649 Depending on board, define exactly one serial port
650 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
651 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
652 console by defining CONFIG_8xx_CONS_NONE
654 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
655 port routines must be defined elsewhere
656 (i.e. serial_init(), serial_getc(), ...)
659 Enables console device for a color framebuffer. Needs following
660 defines (cf. smiLynxEM, i8042)
661 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
663 VIDEO_HW_RECTFILL graphic chip supports
666 VIDEO_HW_BITBLT graphic chip supports
667 bit-blit (cf. smiLynxEM)
668 VIDEO_VISIBLE_COLS visible pixel columns
670 VIDEO_VISIBLE_ROWS visible pixel rows
671 VIDEO_PIXEL_SIZE bytes per pixel
672 VIDEO_DATA_FORMAT graphic data format
673 (0-5, cf. cfb_console.c)
674 VIDEO_FB_ADRS framebuffer address
675 VIDEO_KBD_INIT_FCT keyboard int fct
676 (i.e. i8042_kbd_init())
677 VIDEO_TSTC_FCT test char fct
679 VIDEO_GETC_FCT get char fct
681 CONFIG_CONSOLE_CURSOR cursor drawing on/off
682 (requires blink timer
684 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
685 CONFIG_CONSOLE_TIME display time/date info in
687 (requires CONFIG_CMD_DATE)
688 CONFIG_VIDEO_LOGO display Linux logo in
690 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
691 linux_logo.h for logo.
692 Requires CONFIG_VIDEO_LOGO
693 CONFIG_CONSOLE_EXTRA_INFO
694 additional board info beside
697 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
698 a limited number of ANSI escape sequences (cursor control,
699 erase functions and limited graphics rendition control).
701 When CONFIG_CFB_CONSOLE is defined, video console is
702 default i/o. Serial console can be forced with
703 environment 'console=serial'.
705 When CONFIG_SILENT_CONSOLE is defined, all console
706 messages (by U-Boot and Linux!) can be silenced with
707 the "silent" environment variable. See
708 doc/README.silent for more information.
711 CONFIG_BAUDRATE - in bps
712 Select one of the baudrates listed in
713 CONFIG_SYS_BAUDRATE_TABLE, see below.
714 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
716 - Console Rx buffer length
717 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
718 the maximum receive buffer length for the SMC.
719 This option is actual only for 82xx and 8xx possible.
720 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
721 must be defined, to setup the maximum idle timeout for
724 - Pre-Console Buffer:
725 Prior to the console being initialised (i.e. serial UART
726 initialised etc) all console output is silently discarded.
727 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
728 buffer any console messages prior to the console being
729 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
730 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
731 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
732 bytes are output before the console is initialised, the
733 earlier bytes are discarded.
735 'Sane' compilers will generate smaller code if
736 CONFIG_PRE_CON_BUF_SZ is a power of 2
738 - Safe printf() functions
739 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
740 the printf() functions. These are defined in
741 include/vsprintf.h and include snprintf(), vsnprintf() and
742 so on. Code size increase is approximately 300-500 bytes.
743 If this option is not given then these functions will
744 silently discard their buffer size argument - this means
745 you are not getting any overflow checking in this case.
747 - Boot Delay: CONFIG_BOOTDELAY - in seconds
748 Delay before automatically booting the default image;
749 set to -1 to disable autoboot.
750 set to -2 to autoboot with no delay and not check for abort
751 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
753 See doc/README.autoboot for these options that
754 work with CONFIG_BOOTDELAY. None are required.
755 CONFIG_BOOT_RETRY_TIME
756 CONFIG_BOOT_RETRY_MIN
757 CONFIG_AUTOBOOT_KEYED
758 CONFIG_AUTOBOOT_PROMPT
759 CONFIG_AUTOBOOT_DELAY_STR
760 CONFIG_AUTOBOOT_STOP_STR
761 CONFIG_AUTOBOOT_DELAY_STR2
762 CONFIG_AUTOBOOT_STOP_STR2
763 CONFIG_ZERO_BOOTDELAY_CHECK
764 CONFIG_RESET_TO_RETRY
768 Only needed when CONFIG_BOOTDELAY is enabled;
769 define a command string that is automatically executed
770 when no character is read on the console interface
771 within "Boot Delay" after reset.
774 This can be used to pass arguments to the bootm
775 command. The value of CONFIG_BOOTARGS goes into the
776 environment value "bootargs".
778 CONFIG_RAMBOOT and CONFIG_NFSBOOT
779 The value of these goes into the environment as
780 "ramboot" and "nfsboot" respectively, and can be used
781 as a convenience, when switching between booting from
787 When this option is #defined, the existence of the
788 environment variable "preboot" will be checked
789 immediately before starting the CONFIG_BOOTDELAY
790 countdown and/or running the auto-boot command resp.
791 entering interactive mode.
793 This feature is especially useful when "preboot" is
794 automatically generated or modified. For an example
795 see the LWMON board specific code: here "preboot" is
796 modified when the user holds down a certain
797 combination of keys on the (special) keyboard when
800 - Serial Download Echo Mode:
802 If defined to 1, all characters received during a
803 serial download (using the "loads" command) are
804 echoed back. This might be needed by some terminal
805 emulations (like "cu"), but may as well just take
806 time on others. This setting #define's the initial
807 value of the "loads_echo" environment variable.
809 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
811 Select one of the baudrates listed in
812 CONFIG_SYS_BAUDRATE_TABLE, see below.
815 Monitor commands can be included or excluded
816 from the build by using the #include files
817 <config_cmd_all.h> and #undef'ing unwanted
818 commands, or using <config_cmd_default.h>
819 and augmenting with additional #define's
822 The default command configuration includes all commands
823 except those marked below with a "*".
825 CONFIG_CMD_ASKENV * ask for env variable
826 CONFIG_CMD_BDI bdinfo
827 CONFIG_CMD_BEDBUG * Include BedBug Debugger
828 CONFIG_CMD_BMP * BMP support
829 CONFIG_CMD_BSP * Board specific commands
830 CONFIG_CMD_BOOTD bootd
831 CONFIG_CMD_CACHE * icache, dcache
832 CONFIG_CMD_CONSOLE coninfo
833 CONFIG_CMD_CRC32 * crc32
834 CONFIG_CMD_DATE * support for RTC, date/time...
835 CONFIG_CMD_DHCP * DHCP support
836 CONFIG_CMD_DIAG * Diagnostics
837 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
838 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
839 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
840 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
841 CONFIG_CMD_DTT * Digital Therm and Thermostat
842 CONFIG_CMD_ECHO echo arguments
843 CONFIG_CMD_EDITENV edit env variable
844 CONFIG_CMD_EEPROM * EEPROM read/write support
845 CONFIG_CMD_ELF * bootelf, bootvx
846 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
847 CONFIG_CMD_ENV_FLAGS * display details about env flags
848 CONFIG_CMD_EXPORTENV * export the environment
849 CONFIG_CMD_EXT2 * ext2 command support
850 CONFIG_CMD_EXT4 * ext4 command support
851 CONFIG_CMD_SAVEENV saveenv
852 CONFIG_CMD_FDC * Floppy Disk Support
853 CONFIG_CMD_FAT * FAT command support
854 CONFIG_CMD_FDOS * Dos diskette Support
855 CONFIG_CMD_FLASH flinfo, erase, protect
856 CONFIG_CMD_FPGA FPGA device initialization support
857 CONFIG_CMD_FUSE * Device fuse support
858 CONFIG_CMD_GETTIME * Get time since boot
859 CONFIG_CMD_GO * the 'go' command (exec code)
860 CONFIG_CMD_GREPENV * search environment
861 CONFIG_CMD_HASH * calculate hash / digest
862 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
863 CONFIG_CMD_I2C * I2C serial bus support
864 CONFIG_CMD_IDE * IDE harddisk support
865 CONFIG_CMD_IMI iminfo
866 CONFIG_CMD_IMLS List all images found in NOR flash
867 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash
868 CONFIG_CMD_IMMAP * IMMR dump support
869 CONFIG_CMD_IMPORTENV * import an environment
870 CONFIG_CMD_INI * import data from an ini file into the env
871 CONFIG_CMD_IRQ * irqinfo
872 CONFIG_CMD_ITEST Integer/string test of 2 values
873 CONFIG_CMD_JFFS2 * JFFS2 Support
874 CONFIG_CMD_KGDB * kgdb
875 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader)
876 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
878 CONFIG_CMD_LOADB loadb
879 CONFIG_CMD_LOADS loads
880 CONFIG_CMD_MD5SUM * print md5 message digest
881 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
882 CONFIG_CMD_MEMINFO * Display detailed memory information
883 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
885 CONFIG_CMD_MEMTEST * mtest
886 CONFIG_CMD_MISC Misc functions like sleep etc
887 CONFIG_CMD_MMC * MMC memory mapped support
888 CONFIG_CMD_MII * MII utility commands
889 CONFIG_CMD_MTDPARTS * MTD partition support
890 CONFIG_CMD_NAND * NAND support
891 CONFIG_CMD_NET bootp, tftpboot, rarpboot
892 CONFIG_CMD_NFS NFS support
893 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
894 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
895 CONFIG_CMD_PCI * pciinfo
896 CONFIG_CMD_PCMCIA * PCMCIA support
897 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
899 CONFIG_CMD_PORTIO * Port I/O
900 CONFIG_CMD_READ * Read raw data from partition
901 CONFIG_CMD_REGINFO * Register dump
902 CONFIG_CMD_RUN run command in env variable
903 CONFIG_CMD_SANDBOX * sb command to access sandbox features
904 CONFIG_CMD_SAVES * save S record dump
905 CONFIG_CMD_SCSI * SCSI Support
906 CONFIG_CMD_SDRAM * print SDRAM configuration information
907 (requires CONFIG_CMD_I2C)
908 CONFIG_CMD_SETGETDCR Support for DCR Register access
910 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
911 CONFIG_CMD_SHA1SUM * print sha1 memory digest
912 (requires CONFIG_CMD_MEMORY)
913 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x
914 CONFIG_CMD_SOURCE "source" command Support
915 CONFIG_CMD_SPI * SPI serial bus support
916 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
917 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
918 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
919 CONFIG_CMD_TIMER * access to the system tick timer
920 CONFIG_CMD_USB * USB support
921 CONFIG_CMD_CDP * Cisco Discover Protocol support
922 CONFIG_CMD_MFSL * Microblaze FSL support
923 CONFIG_CMD_XIMG Load part of Multi Image
926 EXAMPLE: If you want all functions except of network
927 support you can write:
929 #include "config_cmd_all.h"
930 #undef CONFIG_CMD_NET
933 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
935 Note: Don't enable the "icache" and "dcache" commands
936 (configuration option CONFIG_CMD_CACHE) unless you know
937 what you (and your U-Boot users) are doing. Data
938 cache cannot be enabled on systems like the 8xx or
939 8260 (where accesses to the IMMR region must be
940 uncached), and it cannot be disabled on all other
941 systems where we (mis-) use the data cache to hold an
942 initial stack and some data.
945 XXX - this list needs to get updated!
947 - Regular expression support:
949 If this variable is defined, U-Boot is linked against
950 the SLRE (Super Light Regular Expression) library,
951 which adds regex support to some commands, as for
952 example "env grep" and "setexpr".
956 If this variable is defined, U-Boot will use a device tree
957 to configure its devices, instead of relying on statically
958 compiled #defines in the board file. This option is
959 experimental and only available on a few boards. The device
960 tree is available in the global data as gd->fdt_blob.
962 U-Boot needs to get its device tree from somewhere. This can
963 be done using one of the two options below:
966 If this variable is defined, U-Boot will embed a device tree
967 binary in its image. This device tree file should be in the
968 board directory and called <soc>-<board>.dts. The binary file
969 is then picked up in board_init_f() and made available through
970 the global data structure as gd->blob.
973 If this variable is defined, U-Boot will build a device tree
974 binary. It will be called u-boot.dtb. Architecture-specific
975 code will locate it at run-time. Generally this works by:
977 cat u-boot.bin u-boot.dtb >image.bin
979 and in fact, U-Boot does this for you, creating a file called
980 u-boot-dtb.bin which is useful in the common case. You can
981 still use the individual files if you need something more
986 If this variable is defined, it enables watchdog
987 support for the SoC. There must be support in the SoC
988 specific code for a watchdog. For the 8xx and 8260
989 CPUs, the SIU Watchdog feature is enabled in the SYPCR
990 register. When supported for a specific SoC is
991 available, then no further board specific code should
995 When using a watchdog circuitry external to the used
996 SoC, then define this variable and provide board
997 specific code for the "hw_watchdog_reset" function.
1000 CONFIG_VERSION_VARIABLE
1001 If this variable is defined, an environment variable
1002 named "ver" is created by U-Boot showing the U-Boot
1003 version as printed by the "version" command.
1004 Any change to this variable will be reverted at the
1009 When CONFIG_CMD_DATE is selected, the type of the RTC
1010 has to be selected, too. Define exactly one of the
1013 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
1014 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
1015 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
1016 CONFIG_RTC_MC146818 - use MC146818 RTC
1017 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
1018 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
1019 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
1020 CONFIG_RTC_DS164x - use Dallas DS164x RTC
1021 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
1022 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
1023 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
1024 CONFIG_SYS_RV3029_TCR - enable trickle charger on
1027 Note that if the RTC uses I2C, then the I2C interface
1028 must also be configured. See I2C Support, below.
1031 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
1032 CONFIG_PCA953X_INFO - enable pca953x info command
1034 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
1035 chip-ngpio pairs that tell the PCA953X driver the number of
1036 pins supported by a particular chip.
1038 Note that if the GPIO device uses I2C, then the I2C interface
1039 must also be configured. See I2C Support, below.
1041 - Timestamp Support:
1043 When CONFIG_TIMESTAMP is selected, the timestamp
1044 (date and time) of an image is printed by image
1045 commands like bootm or iminfo. This option is
1046 automatically enabled when you select CONFIG_CMD_DATE .
1048 - Partition Labels (disklabels) Supported:
1049 Zero or more of the following:
1050 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1051 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1052 Intel architecture, USB sticks, etc.
1053 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1054 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1055 bootloader. Note 2TB partition limit; see
1057 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1059 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1060 CONFIG_CMD_SCSI) you must configure support for at
1061 least one non-MTD partition type as well.
1064 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1065 board configurations files but used nowhere!
1067 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1068 be performed by calling the function
1069 ide_set_reset(int reset)
1070 which has to be defined in a board specific file
1075 Set this to enable ATAPI support.
1080 Set this to enable support for disks larger than 137GB
1081 Also look at CONFIG_SYS_64BIT_LBA.
1082 Whithout these , LBA48 support uses 32bit variables and will 'only'
1083 support disks up to 2.1TB.
1085 CONFIG_SYS_64BIT_LBA:
1086 When enabled, makes the IDE subsystem use 64bit sector addresses.
1090 At the moment only there is only support for the
1091 SYM53C8XX SCSI controller; define
1092 CONFIG_SCSI_SYM53C8XX to enable it.
1094 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1095 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1096 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1097 maximum numbers of LUNs, SCSI ID's and target
1099 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1101 The environment variable 'scsidevs' is set to the number of
1102 SCSI devices found during the last scan.
1104 - NETWORK Support (PCI):
1106 Support for Intel 8254x/8257x gigabit chips.
1109 Utility code for direct access to the SPI bus on Intel 8257x.
1110 This does not do anything useful unless you set at least one
1111 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1113 CONFIG_E1000_SPI_GENERIC
1114 Allow generic access to the SPI bus on the Intel 8257x, for
1115 example with the "sspi" command.
1118 Management command for E1000 devices. When used on devices
1119 with SPI support you can reprogram the EEPROM from U-Boot.
1121 CONFIG_E1000_FALLBACK_MAC
1122 default MAC for empty EEPROM after production.
1125 Support for Intel 82557/82559/82559ER chips.
1126 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1127 write routine for first time initialisation.
1130 Support for Digital 2114x chips.
1131 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1132 modem chip initialisation (KS8761/QS6611).
1135 Support for National dp83815 chips.
1138 Support for National dp8382[01] gigabit chips.
1140 - NETWORK Support (other):
1142 CONFIG_DRIVER_AT91EMAC
1143 Support for AT91RM9200 EMAC.
1146 Define this to use reduced MII inteface
1148 CONFIG_DRIVER_AT91EMAC_QUIET
1149 If this defined, the driver is quiet.
1150 The driver doen't show link status messages.
1152 CONFIG_CALXEDA_XGMAC
1153 Support for the Calxeda XGMAC device
1156 Support for SMSC's LAN91C96 chips.
1158 CONFIG_LAN91C96_BASE
1159 Define this to hold the physical address
1160 of the LAN91C96's I/O space
1162 CONFIG_LAN91C96_USE_32_BIT
1163 Define this to enable 32 bit addressing
1166 Support for SMSC's LAN91C111 chip
1168 CONFIG_SMC91111_BASE
1169 Define this to hold the physical address
1170 of the device (I/O space)
1172 CONFIG_SMC_USE_32_BIT
1173 Define this if data bus is 32 bits
1175 CONFIG_SMC_USE_IOFUNCS
1176 Define this to use i/o functions instead of macros
1177 (some hardware wont work with macros)
1179 CONFIG_DRIVER_TI_EMAC
1180 Support for davinci emac
1182 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1183 Define this if you have more then 3 PHYs.
1186 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1188 CONFIG_FTGMAC100_EGIGA
1189 Define this to use GE link update with gigabit PHY.
1190 Define this if FTGMAC100 is connected to gigabit PHY.
1191 If your system has 10/100 PHY only, it might not occur
1192 wrong behavior. Because PHY usually return timeout or
1193 useless data when polling gigabit status and gigabit
1194 control registers. This behavior won't affect the
1195 correctnessof 10/100 link speed update.
1198 Support for SMSC's LAN911x and LAN921x chips
1201 Define this to hold the physical address
1202 of the device (I/O space)
1204 CONFIG_SMC911X_32_BIT
1205 Define this if data bus is 32 bits
1207 CONFIG_SMC911X_16_BIT
1208 Define this if data bus is 16 bits. If your processor
1209 automatically converts one 32 bit word to two 16 bit
1210 words you may also try CONFIG_SMC911X_32_BIT.
1213 Support for Renesas on-chip Ethernet controller
1215 CONFIG_SH_ETHER_USE_PORT
1216 Define the number of ports to be used
1218 CONFIG_SH_ETHER_PHY_ADDR
1219 Define the ETH PHY's address
1221 CONFIG_SH_ETHER_CACHE_WRITEBACK
1222 If this option is set, the driver enables cache flush.
1226 Support TPM devices.
1229 Support for i2c bus TPM devices. Only one device
1230 per system is supported at this time.
1232 CONFIG_TPM_TIS_I2C_BUS_NUMBER
1233 Define the the i2c bus number for the TPM device
1235 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS
1236 Define the TPM's address on the i2c bus
1238 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
1239 Define the burst count bytes upper limit
1242 Support for generic parallel port TPM devices. Only one device
1243 per system is supported at this time.
1245 CONFIG_TPM_TIS_BASE_ADDRESS
1246 Base address where the generic TPM device is mapped
1247 to. Contemporary x86 systems usually map it at
1251 Add tpm monitor functions.
1252 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also
1253 provides monitor access to authorized functions.
1256 Define this to enable the TPM support library which provides
1257 functional interfaces to some TPM commands.
1258 Requires support for a TPM device.
1260 CONFIG_TPM_AUTH_SESSIONS
1261 Define this to enable authorized functions in the TPM library.
1262 Requires CONFIG_TPM and CONFIG_SHA1.
1265 At the moment only the UHCI host controller is
1266 supported (PIP405, MIP405, MPC5200); define
1267 CONFIG_USB_UHCI to enable it.
1268 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1269 and define CONFIG_USB_STORAGE to enable the USB
1272 Supported are USB Keyboards and USB Floppy drives
1274 MPC5200 USB requires additional defines:
1276 for 528 MHz Clock: 0x0001bbbb
1280 for differential drivers: 0x00001000
1281 for single ended drivers: 0x00005000
1282 for differential drivers on PSC3: 0x00000100
1283 for single ended drivers on PSC3: 0x00004100
1284 CONFIG_SYS_USB_EVENT_POLL
1285 May be defined to allow interrupt polling
1286 instead of using asynchronous interrupts
1288 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1289 txfilltuning field in the EHCI controller on reset.
1291 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum
1292 interval for usb hub power-on delay.(minimum 100msec)
1295 Define the below if you wish to use the USB console.
1296 Once firmware is rebuilt from a serial console issue the
1297 command "setenv stdin usbtty; setenv stdout usbtty" and
1298 attach your USB cable. The Unix command "dmesg" should print
1299 it has found a new device. The environment variable usbtty
1300 can be set to gserial or cdc_acm to enable your device to
1301 appear to a USB host as a Linux gserial device or a
1302 Common Device Class Abstract Control Model serial device.
1303 If you select usbtty = gserial you should be able to enumerate
1305 # modprobe usbserial vendor=0xVendorID product=0xProductID
1306 else if using cdc_acm, simply setting the environment
1307 variable usbtty to be cdc_acm should suffice. The following
1308 might be defined in YourBoardName.h
1311 Define this to build a UDC device
1314 Define this to have a tty type of device available to
1315 talk to the UDC device
1318 Define this to enable the high speed support for usb
1319 device and usbtty. If this feature is enabled, a routine
1320 int is_usbd_high_speed(void)
1321 also needs to be defined by the driver to dynamically poll
1322 whether the enumeration has succeded at high speed or full
1325 CONFIG_SYS_CONSOLE_IS_IN_ENV
1326 Define this if you want stdin, stdout &/or stderr to
1330 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1331 Derive USB clock from external clock "blah"
1332 - CONFIG_SYS_USB_EXTC_CLK 0x02
1334 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1335 Derive USB clock from brgclk
1336 - CONFIG_SYS_USB_BRG_CLK 0x04
1338 If you have a USB-IF assigned VendorID then you may wish to
1339 define your own vendor specific values either in BoardName.h
1340 or directly in usbd_vendor_info.h. If you don't define
1341 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1342 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1343 should pretend to be a Linux device to it's target host.
1345 CONFIG_USBD_MANUFACTURER
1346 Define this string as the name of your company for
1347 - CONFIG_USBD_MANUFACTURER "my company"
1349 CONFIG_USBD_PRODUCT_NAME
1350 Define this string as the name of your product
1351 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1353 CONFIG_USBD_VENDORID
1354 Define this as your assigned Vendor ID from the USB
1355 Implementors Forum. This *must* be a genuine Vendor ID
1356 to avoid polluting the USB namespace.
1357 - CONFIG_USBD_VENDORID 0xFFFF
1359 CONFIG_USBD_PRODUCTID
1360 Define this as the unique Product ID
1362 - CONFIG_USBD_PRODUCTID 0xFFFF
1364 - ULPI Layer Support:
1365 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1366 the generic ULPI layer. The generic layer accesses the ULPI PHY
1367 via the platform viewport, so you need both the genric layer and
1368 the viewport enabled. Currently only Chipidea/ARC based
1369 viewport is supported.
1370 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1371 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1372 If your ULPI phy needs a different reference clock than the
1373 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1374 the appropriate value in Hz.
1377 The MMC controller on the Intel PXA is supported. To
1378 enable this define CONFIG_MMC. The MMC can be
1379 accessed from the boot prompt by mapping the device
1380 to physical memory similar to flash. Command line is
1381 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1382 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1385 Support for Renesas on-chip MMCIF controller
1387 CONFIG_SH_MMCIF_ADDR
1388 Define the base address of MMCIF registers
1391 Define the clock frequency for MMCIF
1393 - USB Device Firmware Update (DFU) class support:
1395 This enables the USB portion of the DFU USB class
1398 This enables the command "dfu" which is used to have
1399 U-Boot create a DFU class device via USB. This command
1400 requires that the "dfu_alt_info" environment variable be
1401 set and define the alt settings to expose to the host.
1404 This enables support for exposing (e)MMC devices via DFU.
1407 This enables support for exposing NAND devices via DFU.
1409 CONFIG_SYS_DFU_DATA_BUF_SIZE
1410 Dfu transfer uses a buffer before writing data to the
1411 raw storage device. Make the size (in bytes) of this buffer
1412 configurable. The size of this buffer is also configurable
1413 through the "dfu_bufsiz" environment variable.
1415 CONFIG_SYS_DFU_MAX_FILE_SIZE
1416 When updating files rather than the raw storage device,
1417 we use a static buffer to copy the file into and then write
1418 the buffer once we've been given the whole file. Define
1419 this to the maximum filesize (in bytes) for the buffer.
1420 Default is 4 MiB if undefined.
1422 - Journaling Flash filesystem support:
1423 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1424 CONFIG_JFFS2_NAND_DEV
1425 Define these for a default partition on a NAND device
1427 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1428 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1429 Define these for a default partition on a NOR device
1431 CONFIG_SYS_JFFS_CUSTOM_PART
1432 Define this to create an own partition. You have to provide a
1433 function struct part_info* jffs2_part_info(int part_num)
1435 If you define only one JFFS2 partition you may also want to
1436 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1437 to disable the command chpart. This is the default when you
1438 have not defined a custom partition
1440 - FAT(File Allocation Table) filesystem write function support:
1443 Define this to enable support for saving memory data as a
1444 file in FAT formatted partition.
1446 This will also enable the command "fatwrite" enabling the
1447 user to write files to FAT.
1449 CBFS (Coreboot Filesystem) support
1452 Define this to enable support for reading from a Coreboot
1453 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1459 Define this to enable standard (PC-Style) keyboard
1463 Standard PC keyboard driver with US (is default) and
1464 GERMAN key layout (switch via environment 'keymap=de') support.
1465 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1466 for cfb_console. Supports cursor blinking.
1469 Enables a Chrome OS keyboard using the CROS_EC interface.
1470 This uses CROS_EC to communicate with a second microcontroller
1471 which provides key scans on request.
1476 Define this to enable video support (for output to
1479 CONFIG_VIDEO_CT69000
1481 Enable Chips & Technologies 69000 Video chip
1483 CONFIG_VIDEO_SMI_LYNXEM
1484 Enable Silicon Motion SMI 712/710/810 Video chip. The
1485 video output is selected via environment 'videoout'
1486 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1489 For the CT69000 and SMI_LYNXEM drivers, videomode is
1490 selected via environment 'videomode'. Two different ways
1492 - "videomode=num" 'num' is a standard LiLo mode numbers.
1493 Following standard modes are supported (* is default):
1495 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1496 -------------+---------------------------------------------
1497 8 bits | 0x301* 0x303 0x305 0x161 0x307
1498 15 bits | 0x310 0x313 0x316 0x162 0x319
1499 16 bits | 0x311 0x314 0x317 0x163 0x31A
1500 24 bits | 0x312 0x315 0x318 ? 0x31B
1501 -------------+---------------------------------------------
1502 (i.e. setenv videomode 317; saveenv; reset;)
1504 - "videomode=bootargs" all the video parameters are parsed
1505 from the bootargs. (See drivers/video/videomodes.c)
1508 CONFIG_VIDEO_SED13806
1509 Enable Epson SED13806 driver. This driver supports 8bpp
1510 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1511 or CONFIG_VIDEO_SED13806_16BPP
1514 Enable the Freescale DIU video driver. Reference boards for
1515 SOCs that have a DIU should define this macro to enable DIU
1516 support, and should also define these other macros:
1522 CONFIG_VIDEO_SW_CURSOR
1523 CONFIG_VGA_AS_SINGLE_DEVICE
1525 CONFIG_VIDEO_BMP_LOGO
1527 The DIU driver will look for the 'video-mode' environment
1528 variable, and if defined, enable the DIU as a console during
1529 boot. See the documentation file README.video for a
1530 description of this variable.
1534 Enable the VGA video / BIOS for x86. The alternative if you
1535 are using coreboot is to use the coreboot frame buffer
1542 Define this to enable a custom keyboard support.
1543 This simply calls drv_keyboard_init() which must be
1544 defined in your board-specific files.
1545 The only board using this so far is RBC823.
1547 - LCD Support: CONFIG_LCD
1549 Define this to enable LCD support (for output to LCD
1550 display); also select one of the supported displays
1551 by defining one of these:
1555 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1557 CONFIG_NEC_NL6448AC33:
1559 NEC NL6448AC33-18. Active, color, single scan.
1561 CONFIG_NEC_NL6448BC20
1563 NEC NL6448BC20-08. 6.5", 640x480.
1564 Active, color, single scan.
1566 CONFIG_NEC_NL6448BC33_54
1568 NEC NL6448BC33-54. 10.4", 640x480.
1569 Active, color, single scan.
1573 Sharp 320x240. Active, color, single scan.
1574 It isn't 16x9, and I am not sure what it is.
1576 CONFIG_SHARP_LQ64D341
1578 Sharp LQ64D341 display, 640x480.
1579 Active, color, single scan.
1583 HLD1045 display, 640x480.
1584 Active, color, single scan.
1588 Optrex CBL50840-2 NF-FW 99 22 M5
1590 Hitachi LMG6912RPFC-00T
1594 320x240. Black & white.
1596 Normally display is black on white background; define
1597 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1599 CONFIG_LCD_ALIGNMENT
1601 Normally the LCD is page-aligned (tyically 4KB). If this is
1602 defined then the LCD will be aligned to this value instead.
1603 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1604 here, since it is cheaper to change data cache settings on
1605 a per-section basis.
1607 CONFIG_CONSOLE_SCROLL_LINES
1609 When the console need to be scrolled, this is the number of
1610 lines to scroll by. It defaults to 1. Increasing this makes
1611 the console jump but can help speed up operation when scrolling
1616 Support drawing of RLE8-compressed bitmaps on the LCD.
1620 Enables an 'i2c edid' command which can read EDID
1621 information over I2C from an attached LCD display.
1623 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1625 If this option is set, the environment is checked for
1626 a variable "splashimage". If found, the usual display
1627 of logo, copyright and system information on the LCD
1628 is suppressed and the BMP image at the address
1629 specified in "splashimage" is loaded instead. The
1630 console is redirected to the "nulldev", too. This
1631 allows for a "silent" boot where a splash screen is
1632 loaded very quickly after power-on.
1634 CONFIG_SPLASHIMAGE_GUARD
1636 If this option is set, then U-Boot will prevent the environment
1637 variable "splashimage" from being set to a problematic address
1638 (see README.displaying-bmps and README.arm-unaligned-accesses).
1639 This option is useful for targets where, due to alignment
1640 restrictions, an improperly aligned BMP image will cause a data
1641 abort. If you think you will not have problems with unaligned
1642 accesses (for example because your toolchain prevents them)
1643 there is no need to set this option.
1645 CONFIG_SPLASH_SCREEN_ALIGN
1647 If this option is set the splash image can be freely positioned
1648 on the screen. Environment variable "splashpos" specifies the
1649 position as "x,y". If a positive number is given it is used as
1650 number of pixel from left/top. If a negative number is given it
1651 is used as number of pixel from right/bottom. You can also
1652 specify 'm' for centering the image.
1655 setenv splashpos m,m
1656 => image at center of screen
1658 setenv splashpos 30,20
1659 => image at x = 30 and y = 20
1661 setenv splashpos -10,m
1662 => vertically centered image
1663 at x = dspWidth - bmpWidth - 9
1665 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1667 If this option is set, additionally to standard BMP
1668 images, gzipped BMP images can be displayed via the
1669 splashscreen support or the bmp command.
1671 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1673 If this option is set, 8-bit RLE compressed BMP images
1674 can be displayed via the splashscreen support or the
1677 - Do compresssing for memory range:
1680 If this option is set, it would use zlib deflate method
1681 to compress the specified memory at its best effort.
1683 - Compression support:
1686 If this option is set, support for bzip2 compressed
1687 images is included. If not, only uncompressed and gzip
1688 compressed images are supported.
1690 NOTE: the bzip2 algorithm requires a lot of RAM, so
1691 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1696 If this option is set, support for lzma compressed
1699 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1700 requires an amount of dynamic memory that is given by the
1703 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1705 Where lc and lp stand for, respectively, Literal context bits
1706 and Literal pos bits.
1708 This value is upper-bounded by 14MB in the worst case. Anyway,
1709 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1710 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1711 a very small buffer.
1713 Use the lzmainfo tool to determinate the lc and lp values and
1714 then calculate the amount of needed dynamic memory (ensuring
1715 the appropriate CONFIG_SYS_MALLOC_LEN value).
1720 The address of PHY on MII bus.
1722 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1724 The clock frequency of the MII bus
1728 If this option is set, support for speed/duplex
1729 detection of gigabit PHY is included.
1731 CONFIG_PHY_RESET_DELAY
1733 Some PHY like Intel LXT971A need extra delay after
1734 reset before any MII register access is possible.
1735 For such PHY, set this option to the usec delay
1736 required. (minimum 300usec for LXT971A)
1738 CONFIG_PHY_CMD_DELAY (ppc4xx)
1740 Some PHY like Intel LXT971A need extra delay after
1741 command issued before MII status register can be read
1751 Define a default value for Ethernet address to use
1752 for the respective Ethernet interface, in case this
1753 is not determined automatically.
1758 Define a default value for the IP address to use for
1759 the default Ethernet interface, in case this is not
1760 determined through e.g. bootp.
1761 (Environment variable "ipaddr")
1763 - Server IP address:
1766 Defines a default value for the IP address of a TFTP
1767 server to contact when using the "tftboot" command.
1768 (Environment variable "serverip")
1770 CONFIG_KEEP_SERVERADDR
1772 Keeps the server's MAC address, in the env 'serveraddr'
1773 for passing to bootargs (like Linux's netconsole option)
1775 - Gateway IP address:
1778 Defines a default value for the IP address of the
1779 default router where packets to other networks are
1781 (Environment variable "gatewayip")
1786 Defines a default value for the subnet mask (or
1787 routing prefix) which is used to determine if an IP
1788 address belongs to the local subnet or needs to be
1789 forwarded through a router.
1790 (Environment variable "netmask")
1792 - Multicast TFTP Mode:
1795 Defines whether you want to support multicast TFTP as per
1796 rfc-2090; for example to work with atftp. Lets lots of targets
1797 tftp down the same boot image concurrently. Note: the Ethernet
1798 driver in use must provide a function: mcast() to join/leave a
1801 - BOOTP Recovery Mode:
1802 CONFIG_BOOTP_RANDOM_DELAY
1804 If you have many targets in a network that try to
1805 boot using BOOTP, you may want to avoid that all
1806 systems send out BOOTP requests at precisely the same
1807 moment (which would happen for instance at recovery
1808 from a power failure, when all systems will try to
1809 boot, thus flooding the BOOTP server. Defining
1810 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1811 inserted before sending out BOOTP requests. The
1812 following delays are inserted then:
1814 1st BOOTP request: delay 0 ... 1 sec
1815 2nd BOOTP request: delay 0 ... 2 sec
1816 3rd BOOTP request: delay 0 ... 4 sec
1818 BOOTP requests: delay 0 ... 8 sec
1820 - DHCP Advanced Options:
1821 You can fine tune the DHCP functionality by defining
1822 CONFIG_BOOTP_* symbols:
1824 CONFIG_BOOTP_SUBNETMASK
1825 CONFIG_BOOTP_GATEWAY
1826 CONFIG_BOOTP_HOSTNAME
1827 CONFIG_BOOTP_NISDOMAIN
1828 CONFIG_BOOTP_BOOTPATH
1829 CONFIG_BOOTP_BOOTFILESIZE
1832 CONFIG_BOOTP_SEND_HOSTNAME
1833 CONFIG_BOOTP_NTPSERVER
1834 CONFIG_BOOTP_TIMEOFFSET
1835 CONFIG_BOOTP_VENDOREX
1836 CONFIG_BOOTP_MAY_FAIL
1838 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1839 environment variable, not the BOOTP server.
1841 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1842 after the configured retry count, the call will fail
1843 instead of starting over. This can be used to fail over
1844 to Link-local IP address configuration if the DHCP server
1847 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1848 serverip from a DHCP server, it is possible that more
1849 than one DNS serverip is offered to the client.
1850 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1851 serverip will be stored in the additional environment
1852 variable "dnsip2". The first DNS serverip is always
1853 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1856 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1857 to do a dynamic update of a DNS server. To do this, they
1858 need the hostname of the DHCP requester.
1859 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1860 of the "hostname" environment variable is passed as
1861 option 12 to the DHCP server.
1863 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1865 A 32bit value in microseconds for a delay between
1866 receiving a "DHCP Offer" and sending the "DHCP Request".
1867 This fixes a problem with certain DHCP servers that don't
1868 respond 100% of the time to a "DHCP request". E.g. On an
1869 AT91RM9200 processor running at 180MHz, this delay needed
1870 to be *at least* 15,000 usec before a Windows Server 2003
1871 DHCP server would reply 100% of the time. I recommend at
1872 least 50,000 usec to be safe. The alternative is to hope
1873 that one of the retries will be successful but note that
1874 the DHCP timeout and retry process takes a longer than
1877 - Link-local IP address negotiation:
1878 Negotiate with other link-local clients on the local network
1879 for an address that doesn't require explicit configuration.
1880 This is especially useful if a DHCP server cannot be guaranteed
1881 to exist in all environments that the device must operate.
1883 See doc/README.link-local for more information.
1886 CONFIG_CDP_DEVICE_ID
1888 The device id used in CDP trigger frames.
1890 CONFIG_CDP_DEVICE_ID_PREFIX
1892 A two character string which is prefixed to the MAC address
1897 A printf format string which contains the ascii name of
1898 the port. Normally is set to "eth%d" which sets
1899 eth0 for the first Ethernet, eth1 for the second etc.
1901 CONFIG_CDP_CAPABILITIES
1903 A 32bit integer which indicates the device capabilities;
1904 0x00000010 for a normal host which does not forwards.
1908 An ascii string containing the version of the software.
1912 An ascii string containing the name of the platform.
1916 A 32bit integer sent on the trigger.
1918 CONFIG_CDP_POWER_CONSUMPTION
1920 A 16bit integer containing the power consumption of the
1921 device in .1 of milliwatts.
1923 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1925 A byte containing the id of the VLAN.
1927 - Status LED: CONFIG_STATUS_LED
1929 Several configurations allow to display the current
1930 status using a LED. For instance, the LED will blink
1931 fast while running U-Boot code, stop blinking as
1932 soon as a reply to a BOOTP request was received, and
1933 start blinking slow once the Linux kernel is running
1934 (supported by a status LED driver in the Linux
1935 kernel). Defining CONFIG_STATUS_LED enables this
1938 - CAN Support: CONFIG_CAN_DRIVER
1940 Defining CONFIG_CAN_DRIVER enables CAN driver support
1941 on those systems that support this (optional)
1942 feature, like the TQM8xxL modules.
1944 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1946 These enable I2C serial bus commands. Defining either of
1947 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1948 include the appropriate I2C driver for the selected CPU.
1950 This will allow you to use i2c commands at the u-boot
1951 command line (as long as you set CONFIG_CMD_I2C in
1952 CONFIG_COMMANDS) and communicate with i2c based realtime
1953 clock chips. See common/cmd_i2c.c for a description of the
1954 command line interface.
1956 CONFIG_HARD_I2C selects a hardware I2C controller.
1958 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1959 bit-banging) driver instead of CPM or similar hardware
1962 There are several other quantities that must also be
1963 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1965 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1966 to be the frequency (in Hz) at which you wish your i2c bus
1967 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1968 the CPU's i2c node address).
1970 Now, the u-boot i2c code for the mpc8xx
1971 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1972 and so its address should therefore be cleared to 0 (See,
1973 eg, MPC823e User's Manual p.16-473). So, set
1974 CONFIG_SYS_I2C_SLAVE to 0.
1976 CONFIG_SYS_I2C_INIT_MPC5XXX
1978 When a board is reset during an i2c bus transfer
1979 chips might think that the current transfer is still
1980 in progress. Reset the slave devices by sending start
1981 commands until the slave device responds.
1983 That's all that's required for CONFIG_HARD_I2C.
1985 If you use the software i2c interface (CONFIG_SOFT_I2C)
1986 then the following macros need to be defined (examples are
1987 from include/configs/lwmon.h):
1991 (Optional). Any commands necessary to enable the I2C
1992 controller or configure ports.
1994 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1998 (Only for MPC8260 CPU). The I/O port to use (the code
1999 assumes both bits are on the same port). Valid values
2000 are 0..3 for ports A..D.
2004 The code necessary to make the I2C data line active
2005 (driven). If the data line is open collector, this
2008 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
2012 The code necessary to make the I2C data line tri-stated
2013 (inactive). If the data line is open collector, this
2016 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
2020 Code that returns true if the I2C data line is high,
2023 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
2027 If <bit> is true, sets the I2C data line high. If it
2028 is false, it clears it (low).
2030 eg: #define I2C_SDA(bit) \
2031 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
2032 else immr->im_cpm.cp_pbdat &= ~PB_SDA
2036 If <bit> is true, sets the I2C clock line high. If it
2037 is false, it clears it (low).
2039 eg: #define I2C_SCL(bit) \
2040 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
2041 else immr->im_cpm.cp_pbdat &= ~PB_SCL
2045 This delay is invoked four times per clock cycle so this
2046 controls the rate of data transfer. The data rate thus
2047 is 1 / (I2C_DELAY * 4). Often defined to be something
2050 #define I2C_DELAY udelay(2)
2052 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
2054 If your arch supports the generic GPIO framework (asm/gpio.h),
2055 then you may alternatively define the two GPIOs that are to be
2056 used as SCL / SDA. Any of the previous I2C_xxx macros will
2057 have GPIO-based defaults assigned to them as appropriate.
2059 You should define these to the GPIO value as given directly to
2060 the generic GPIO functions.
2062 CONFIG_SYS_I2C_INIT_BOARD
2064 When a board is reset during an i2c bus transfer
2065 chips might think that the current transfer is still
2066 in progress. On some boards it is possible to access
2067 the i2c SCLK line directly, either by using the
2068 processor pin as a GPIO or by having a second pin
2069 connected to the bus. If this option is defined a
2070 custom i2c_init_board() routine in boards/xxx/board.c
2071 is run early in the boot sequence.
2073 CONFIG_SYS_I2C_BOARD_LATE_INIT
2075 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
2076 defined a custom i2c_board_late_init() routine in
2077 boards/xxx/board.c is run AFTER the operations in i2c_init()
2078 is completed. This callpoint can be used to unreset i2c bus
2079 using CPU i2c controller register accesses for CPUs whose i2c
2080 controller provide such a method. It is called at the end of
2081 i2c_init() to allow i2c_init operations to setup the i2c bus
2082 controller on the CPU (e.g. setting bus speed & slave address).
2084 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
2086 This option enables configuration of bi_iic_fast[] flags
2087 in u-boot bd_info structure based on u-boot environment
2088 variable "i2cfast". (see also i2cfast)
2090 CONFIG_I2C_MULTI_BUS
2092 This option allows the use of multiple I2C buses, each of which
2093 must have a controller. At any point in time, only one bus is
2094 active. To switch to a different bus, use the 'i2c dev' command.
2095 Note that bus numbering is zero-based.
2097 CONFIG_SYS_I2C_NOPROBES
2099 This option specifies a list of I2C devices that will be skipped
2100 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
2101 is set, specify a list of bus-device pairs. Otherwise, specify
2102 a 1D array of device addresses
2105 #undef CONFIG_I2C_MULTI_BUS
2106 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
2108 will skip addresses 0x50 and 0x68 on a board with one I2C bus
2110 #define CONFIG_I2C_MULTI_BUS
2111 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
2113 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
2115 CONFIG_SYS_SPD_BUS_NUM
2117 If defined, then this indicates the I2C bus number for DDR SPD.
2118 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
2120 CONFIG_SYS_RTC_BUS_NUM
2122 If defined, then this indicates the I2C bus number for the RTC.
2123 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
2125 CONFIG_SYS_DTT_BUS_NUM
2127 If defined, then this indicates the I2C bus number for the DTT.
2128 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
2130 CONFIG_SYS_I2C_DTT_ADDR:
2132 If defined, specifies the I2C address of the DTT device.
2133 If not defined, then U-Boot uses predefined value for
2134 specified DTT device.
2138 Define this option if you want to use Freescale's I2C driver in
2139 drivers/i2c/fsl_i2c.c.
2143 Define this option if you have I2C devices reached over 1 .. n
2144 I2C Muxes like the pca9544a. This option addes a new I2C
2145 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
2146 new I2C Bus to the existing I2C Busses. If you select the
2147 new Bus with "i2c dev", u-bbot sends first the commandos for
2148 the muxes to activate this new "bus".
2150 CONFIG_I2C_MULTI_BUS must be also defined, to use this
2154 Adding a new I2C Bus reached over 2 pca9544a muxes
2155 The First mux with address 70 and channel 6
2156 The Second mux with address 71 and channel 4
2158 => i2c bus pca9544a:70:6:pca9544a:71:4
2160 Use the "i2c bus" command without parameter, to get a list
2161 of I2C Busses with muxes:
2164 Busses reached over muxes:
2166 reached over Mux(es):
2169 reached over Mux(es):
2174 If you now switch to the new I2C Bus 3 with "i2c dev 3"
2175 u-boot first sends the command to the mux@70 to enable
2176 channel 6, and then the command to the mux@71 to enable
2179 After that, you can use the "normal" i2c commands as
2180 usual to communicate with your I2C devices behind
2183 This option is actually implemented for the bitbanging
2184 algorithm in common/soft_i2c.c and for the Hardware I2C
2185 Bus on the MPC8260. But it should be not so difficult
2186 to add this option to other architectures.
2188 CONFIG_SOFT_I2C_READ_REPEATED_START
2190 defining this will force the i2c_read() function in
2191 the soft_i2c driver to perform an I2C repeated start
2192 between writing the address pointer and reading the
2193 data. If this define is omitted the default behaviour
2194 of doing a stop-start sequence will be used. Most I2C
2195 devices can use either method, but some require one or
2198 - SPI Support: CONFIG_SPI
2200 Enables SPI driver (so far only tested with
2201 SPI EEPROM, also an instance works with Crystal A/D and
2202 D/As on the SACSng board)
2206 Enables the driver for SPI controller on SuperH. Currently
2207 only SH7757 is supported.
2211 Enables extended (16-bit) SPI EEPROM addressing.
2212 (symmetrical to CONFIG_I2C_X)
2216 Enables a software (bit-bang) SPI driver rather than
2217 using hardware support. This is a general purpose
2218 driver that only requires three general I/O port pins
2219 (two outputs, one input) to function. If this is
2220 defined, the board configuration must define several
2221 SPI configuration items (port pins to use, etc). For
2222 an example, see include/configs/sacsng.h.
2226 Enables a hardware SPI driver for general-purpose reads
2227 and writes. As with CONFIG_SOFT_SPI, the board configuration
2228 must define a list of chip-select function pointers.
2229 Currently supported on some MPC8xxx processors. For an
2230 example, see include/configs/mpc8349emds.h.
2234 Enables the driver for the SPI controllers on i.MX and MXC
2235 SoCs. Currently i.MX31/35/51 are supported.
2237 - FPGA Support: CONFIG_FPGA
2239 Enables FPGA subsystem.
2241 CONFIG_FPGA_<vendor>
2243 Enables support for specific chip vendors.
2246 CONFIG_FPGA_<family>
2248 Enables support for FPGA family.
2249 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2253 Specify the number of FPGA devices to support.
2255 CONFIG_SYS_FPGA_PROG_FEEDBACK
2257 Enable printing of hash marks during FPGA configuration.
2259 CONFIG_SYS_FPGA_CHECK_BUSY
2261 Enable checks on FPGA configuration interface busy
2262 status by the configuration function. This option
2263 will require a board or device specific function to
2268 If defined, a function that provides delays in the FPGA
2269 configuration driver.
2271 CONFIG_SYS_FPGA_CHECK_CTRLC
2272 Allow Control-C to interrupt FPGA configuration
2274 CONFIG_SYS_FPGA_CHECK_ERROR
2276 Check for configuration errors during FPGA bitfile
2277 loading. For example, abort during Virtex II
2278 configuration if the INIT_B line goes low (which
2279 indicated a CRC error).
2281 CONFIG_SYS_FPGA_WAIT_INIT
2283 Maximum time to wait for the INIT_B line to deassert
2284 after PROB_B has been deasserted during a Virtex II
2285 FPGA configuration sequence. The default time is 500
2288 CONFIG_SYS_FPGA_WAIT_BUSY
2290 Maximum time to wait for BUSY to deassert during
2291 Virtex II FPGA configuration. The default is 5 ms.
2293 CONFIG_SYS_FPGA_WAIT_CONFIG
2295 Time to wait after FPGA configuration. The default is
2298 - Configuration Management:
2301 If defined, this string will be added to the U-Boot
2302 version information (U_BOOT_VERSION)
2304 - Vendor Parameter Protection:
2306 U-Boot considers the values of the environment
2307 variables "serial#" (Board Serial Number) and
2308 "ethaddr" (Ethernet Address) to be parameters that
2309 are set once by the board vendor / manufacturer, and
2310 protects these variables from casual modification by
2311 the user. Once set, these variables are read-only,
2312 and write or delete attempts are rejected. You can
2313 change this behaviour:
2315 If CONFIG_ENV_OVERWRITE is #defined in your config
2316 file, the write protection for vendor parameters is
2317 completely disabled. Anybody can change or delete
2320 Alternatively, if you #define _both_ CONFIG_ETHADDR
2321 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2322 Ethernet address is installed in the environment,
2323 which can be changed exactly ONCE by the user. [The
2324 serial# is unaffected by this, i. e. it remains
2327 The same can be accomplished in a more flexible way
2328 for any variable by configuring the type of access
2329 to allow for those variables in the ".flags" variable
2330 or define CONFIG_ENV_FLAGS_LIST_STATIC.
2335 Define this variable to enable the reservation of
2336 "protected RAM", i. e. RAM which is not overwritten
2337 by U-Boot. Define CONFIG_PRAM to hold the number of
2338 kB you want to reserve for pRAM. You can overwrite
2339 this default value by defining an environment
2340 variable "pram" to the number of kB you want to
2341 reserve. Note that the board info structure will
2342 still show the full amount of RAM. If pRAM is
2343 reserved, a new environment variable "mem" will
2344 automatically be defined to hold the amount of
2345 remaining RAM in a form that can be passed as boot
2346 argument to Linux, for instance like that:
2348 setenv bootargs ... mem=\${mem}
2351 This way you can tell Linux not to use this memory,
2352 either, which results in a memory region that will
2353 not be affected by reboots.
2355 *WARNING* If your board configuration uses automatic
2356 detection of the RAM size, you must make sure that
2357 this memory test is non-destructive. So far, the
2358 following board configurations are known to be
2361 IVMS8, IVML24, SPD8xx, TQM8xxL,
2362 HERMES, IP860, RPXlite, LWMON,
2365 - Access to physical memory region (> 4GB)
2366 Some basic support is provided for operations on memory not
2367 normally accessible to U-Boot - e.g. some architectures
2368 support access to more than 4GB of memory on 32-bit
2369 machines using physical address extension or similar.
2370 Define CONFIG_PHYSMEM to access this basic support, which
2371 currently only supports clearing the memory.
2376 Define this variable to stop the system in case of a
2377 fatal error, so that you have to reset it manually.
2378 This is probably NOT a good idea for an embedded
2379 system where you want the system to reboot
2380 automatically as fast as possible, but it may be
2381 useful during development since you can try to debug
2382 the conditions that lead to the situation.
2384 CONFIG_NET_RETRY_COUNT
2386 This variable defines the number of retries for
2387 network operations like ARP, RARP, TFTP, or BOOTP
2388 before giving up the operation. If not defined, a
2389 default value of 5 is used.
2393 Timeout waiting for an ARP reply in milliseconds.
2397 Timeout in milliseconds used in NFS protocol.
2398 If you encounter "ERROR: Cannot umount" in nfs command,
2399 try longer timeout such as
2400 #define CONFIG_NFS_TIMEOUT 10000UL
2402 - Command Interpreter:
2403 CONFIG_AUTO_COMPLETE
2405 Enable auto completion of commands using TAB.
2407 Note that this feature has NOT been implemented yet
2408 for the "hush" shell.
2411 CONFIG_SYS_HUSH_PARSER
2413 Define this variable to enable the "hush" shell (from
2414 Busybox) as command line interpreter, thus enabling
2415 powerful command line syntax like
2416 if...then...else...fi conditionals or `&&' and '||'
2417 constructs ("shell scripts").
2419 If undefined, you get the old, much simpler behaviour
2420 with a somewhat smaller memory footprint.
2423 CONFIG_SYS_PROMPT_HUSH_PS2
2425 This defines the secondary prompt string, which is
2426 printed when the command interpreter needs more input
2427 to complete a command. Usually "> ".
2431 In the current implementation, the local variables
2432 space and global environment variables space are
2433 separated. Local variables are those you define by
2434 simply typing `name=value'. To access a local
2435 variable later on, you have write `$name' or
2436 `${name}'; to execute the contents of a variable
2437 directly type `$name' at the command prompt.
2439 Global environment variables are those you use
2440 setenv/printenv to work with. To run a command stored
2441 in such a variable, you need to use the run command,
2442 and you must not use the '$' sign to access them.
2444 To store commands and special characters in a
2445 variable, please use double quotation marks
2446 surrounding the whole text of the variable, instead
2447 of the backslashes before semicolons and special
2450 - Commandline Editing and History:
2451 CONFIG_CMDLINE_EDITING
2453 Enable editing and History functions for interactive
2454 commandline input operations
2456 - Default Environment:
2457 CONFIG_EXTRA_ENV_SETTINGS
2459 Define this to contain any number of null terminated
2460 strings (variable = value pairs) that will be part of
2461 the default environment compiled into the boot image.
2463 For example, place something like this in your
2464 board's config file:
2466 #define CONFIG_EXTRA_ENV_SETTINGS \
2470 Warning: This method is based on knowledge about the
2471 internal format how the environment is stored by the
2472 U-Boot code. This is NOT an official, exported
2473 interface! Although it is unlikely that this format
2474 will change soon, there is no guarantee either.
2475 You better know what you are doing here.
2477 Note: overly (ab)use of the default environment is
2478 discouraged. Make sure to check other ways to preset
2479 the environment like the "source" command or the
2482 CONFIG_ENV_VARS_UBOOT_CONFIG
2484 Define this in order to add variables describing the
2485 U-Boot build configuration to the default environment.
2486 These will be named arch, cpu, board, vendor, and soc.
2488 Enabling this option will cause the following to be defined:
2496 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2498 Define this in order to add variables describing certain
2499 run-time determined information about the hardware to the
2500 environment. These will be named board_name, board_rev.
2502 CONFIG_DELAY_ENVIRONMENT
2504 Normally the environment is loaded when the board is
2505 intialised so that it is available to U-Boot. This inhibits
2506 that so that the environment is not available until
2507 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2508 this is instead controlled by the value of
2509 /config/load-environment.
2511 - DataFlash Support:
2512 CONFIG_HAS_DATAFLASH
2514 Defining this option enables DataFlash features and
2515 allows to read/write in Dataflash via the standard
2518 - Serial Flash support
2521 Defining this option enables SPI flash commands
2522 'sf probe/read/write/erase/update'.
2524 Usage requires an initial 'probe' to define the serial
2525 flash parameters, followed by read/write/erase/update
2528 The following defaults may be provided by the platform
2529 to handle the common case when only a single serial
2530 flash is present on the system.
2532 CONFIG_SF_DEFAULT_BUS Bus identifier
2533 CONFIG_SF_DEFAULT_CS Chip-select
2534 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2535 CONFIG_SF_DEFAULT_SPEED in Hz
2539 Define this option to include a destructive SPI flash
2542 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg
2544 Define this option to use the Bank addr/Extended addr
2545 support on SPI flashes which has size > 16Mbytes.
2547 - SystemACE Support:
2550 Adding this option adds support for Xilinx SystemACE
2551 chips attached via some sort of local bus. The address
2552 of the chip must also be defined in the
2553 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2555 #define CONFIG_SYSTEMACE
2556 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2558 When SystemACE support is added, the "ace" device type
2559 becomes available to the fat commands, i.e. fatls.
2561 - TFTP Fixed UDP Port:
2564 If this is defined, the environment variable tftpsrcp
2565 is used to supply the TFTP UDP source port value.
2566 If tftpsrcp isn't defined, the normal pseudo-random port
2567 number generator is used.
2569 Also, the environment variable tftpdstp is used to supply
2570 the TFTP UDP destination port value. If tftpdstp isn't
2571 defined, the normal port 69 is used.
2573 The purpose for tftpsrcp is to allow a TFTP server to
2574 blindly start the TFTP transfer using the pre-configured
2575 target IP address and UDP port. This has the effect of
2576 "punching through" the (Windows XP) firewall, allowing
2577 the remainder of the TFTP transfer to proceed normally.
2578 A better solution is to properly configure the firewall,
2579 but sometimes that is not allowed.
2584 This enables a generic 'hash' command which can produce
2585 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2589 Enable the hash verify command (hash -v). This adds to code
2592 CONFIG_SHA1 - support SHA1 hashing
2593 CONFIG_SHA256 - support SHA256 hashing
2595 Note: There is also a sha1sum command, which should perhaps
2596 be deprecated in favour of 'hash sha1'.
2601 This enables the RSA algorithm used for FIT image verification
2602 in U-Boot. See doc/uImage/signature for more information.
2604 The signing part is build into mkimage regardless of this
2608 - Show boot progress:
2609 CONFIG_SHOW_BOOT_PROGRESS
2611 Defining this option allows to add some board-
2612 specific code (calling a user-provided function
2613 "show_boot_progress(int)") that enables you to show
2614 the system's boot progress on some display (for
2615 example, some LED's) on your board. At the moment,
2616 the following checkpoints are implemented:
2618 - Detailed boot stage timing
2620 Define this option to get detailed timing of each stage
2621 of the boot process.
2623 CONFIG_BOOTSTAGE_USER_COUNT
2624 This is the number of available user bootstage records.
2625 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2626 a new ID will be allocated from this stash. If you exceed
2627 the limit, recording will stop.
2629 CONFIG_BOOTSTAGE_REPORT
2630 Define this to print a report before boot, similar to this:
2632 Timer summary in microseconds:
2635 3,575,678 3,575,678 board_init_f start
2636 3,575,695 17 arch_cpu_init A9
2637 3,575,777 82 arch_cpu_init done
2638 3,659,598 83,821 board_init_r start
2639 3,910,375 250,777 main_loop
2640 29,916,167 26,005,792 bootm_start
2641 30,361,327 445,160 start_kernel
2643 CONFIG_CMD_BOOTSTAGE
2644 Add a 'bootstage' command which supports printing a report
2645 and un/stashing of bootstage data.
2647 CONFIG_BOOTSTAGE_FDT
2648 Stash the bootstage information in the FDT. A root 'bootstage'
2649 node is created with each bootstage id as a child. Each child
2650 has a 'name' property and either 'mark' containing the
2651 mark time in microsecond, or 'accum' containing the
2652 accumulated time for that bootstage id in microseconds.
2657 name = "board_init_f";
2666 Code in the Linux kernel can find this in /proc/devicetree.
2668 Legacy uImage format:
2671 1 common/cmd_bootm.c before attempting to boot an image
2672 -1 common/cmd_bootm.c Image header has bad magic number
2673 2 common/cmd_bootm.c Image header has correct magic number
2674 -2 common/cmd_bootm.c Image header has bad checksum
2675 3 common/cmd_bootm.c Image header has correct checksum
2676 -3 common/cmd_bootm.c Image data has bad checksum
2677 4 common/cmd_bootm.c Image data has correct checksum
2678 -4 common/cmd_bootm.c Image is for unsupported architecture
2679 5 common/cmd_bootm.c Architecture check OK
2680 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2681 6 common/cmd_bootm.c Image Type check OK
2682 -6 common/cmd_bootm.c gunzip uncompression error
2683 -7 common/cmd_bootm.c Unimplemented compression type
2684 7 common/cmd_bootm.c Uncompression OK
2685 8 common/cmd_bootm.c No uncompress/copy overwrite error
2686 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2688 9 common/image.c Start initial ramdisk verification
2689 -10 common/image.c Ramdisk header has bad magic number
2690 -11 common/image.c Ramdisk header has bad checksum
2691 10 common/image.c Ramdisk header is OK
2692 -12 common/image.c Ramdisk data has bad checksum
2693 11 common/image.c Ramdisk data has correct checksum
2694 12 common/image.c Ramdisk verification complete, start loading
2695 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2696 13 common/image.c Start multifile image verification
2697 14 common/image.c No initial ramdisk, no multifile, continue.
2699 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2701 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2702 -31 post/post.c POST test failed, detected by post_output_backlog()
2703 -32 post/post.c POST test failed, detected by post_run_single()
2705 34 common/cmd_doc.c before loading a Image from a DOC device
2706 -35 common/cmd_doc.c Bad usage of "doc" command
2707 35 common/cmd_doc.c correct usage of "doc" command
2708 -36 common/cmd_doc.c No boot device
2709 36 common/cmd_doc.c correct boot device
2710 -37 common/cmd_doc.c Unknown Chip ID on boot device
2711 37 common/cmd_doc.c correct chip ID found, device available
2712 -38 common/cmd_doc.c Read Error on boot device
2713 38 common/cmd_doc.c reading Image header from DOC device OK
2714 -39 common/cmd_doc.c Image header has bad magic number
2715 39 common/cmd_doc.c Image header has correct magic number
2716 -40 common/cmd_doc.c Error reading Image from DOC device
2717 40 common/cmd_doc.c Image header has correct magic number
2718 41 common/cmd_ide.c before loading a Image from a IDE device
2719 -42 common/cmd_ide.c Bad usage of "ide" command
2720 42 common/cmd_ide.c correct usage of "ide" command
2721 -43 common/cmd_ide.c No boot device
2722 43 common/cmd_ide.c boot device found
2723 -44 common/cmd_ide.c Device not available
2724 44 common/cmd_ide.c Device available
2725 -45 common/cmd_ide.c wrong partition selected
2726 45 common/cmd_ide.c partition selected
2727 -46 common/cmd_ide.c Unknown partition table
2728 46 common/cmd_ide.c valid partition table found
2729 -47 common/cmd_ide.c Invalid partition type
2730 47 common/cmd_ide.c correct partition type
2731 -48 common/cmd_ide.c Error reading Image Header on boot device
2732 48 common/cmd_ide.c reading Image Header from IDE device OK
2733 -49 common/cmd_ide.c Image header has bad magic number
2734 49 common/cmd_ide.c Image header has correct magic number
2735 -50 common/cmd_ide.c Image header has bad checksum
2736 50 common/cmd_ide.c Image header has correct checksum
2737 -51 common/cmd_ide.c Error reading Image from IDE device
2738 51 common/cmd_ide.c reading Image from IDE device OK
2739 52 common/cmd_nand.c before loading a Image from a NAND device
2740 -53 common/cmd_nand.c Bad usage of "nand" command
2741 53 common/cmd_nand.c correct usage of "nand" command
2742 -54 common/cmd_nand.c No boot device
2743 54 common/cmd_nand.c boot device found
2744 -55 common/cmd_nand.c Unknown Chip ID on boot device
2745 55 common/cmd_nand.c correct chip ID found, device available
2746 -56 common/cmd_nand.c Error reading Image Header on boot device
2747 56 common/cmd_nand.c reading Image Header from NAND device OK
2748 -57 common/cmd_nand.c Image header has bad magic number
2749 57 common/cmd_nand.c Image header has correct magic number
2750 -58 common/cmd_nand.c Error reading Image from NAND device
2751 58 common/cmd_nand.c reading Image from NAND device OK
2753 -60 common/env_common.c Environment has a bad CRC, using default
2755 64 net/eth.c starting with Ethernet configuration.
2756 -64 net/eth.c no Ethernet found.
2757 65 net/eth.c Ethernet found.
2759 -80 common/cmd_net.c usage wrong
2760 80 common/cmd_net.c before calling NetLoop()
2761 -81 common/cmd_net.c some error in NetLoop() occurred
2762 81 common/cmd_net.c NetLoop() back without error
2763 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2764 82 common/cmd_net.c trying automatic boot
2765 83 common/cmd_net.c running "source" command
2766 -83 common/cmd_net.c some error in automatic boot or "source" command
2767 84 common/cmd_net.c end without errors
2772 100 common/cmd_bootm.c Kernel FIT Image has correct format
2773 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2774 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2775 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2776 102 common/cmd_bootm.c Kernel unit name specified
2777 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2778 103 common/cmd_bootm.c Found configuration node
2779 104 common/cmd_bootm.c Got kernel subimage node offset
2780 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2781 105 common/cmd_bootm.c Kernel subimage hash verification OK
2782 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2783 106 common/cmd_bootm.c Architecture check OK
2784 -106 common/cmd_bootm.c Kernel subimage has wrong type
2785 107 common/cmd_bootm.c Kernel subimage type OK
2786 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2787 108 common/cmd_bootm.c Got kernel subimage data/size
2788 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2789 -109 common/cmd_bootm.c Can't get kernel subimage type
2790 -110 common/cmd_bootm.c Can't get kernel subimage comp
2791 -111 common/cmd_bootm.c Can't get kernel subimage os
2792 -112 common/cmd_bootm.c Can't get kernel subimage load address
2793 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2795 120 common/image.c Start initial ramdisk verification
2796 -120 common/image.c Ramdisk FIT image has incorrect format
2797 121 common/image.c Ramdisk FIT image has correct format
2798 122 common/image.c No ramdisk subimage unit name, using configuration
2799 -122 common/image.c Can't get configuration for ramdisk subimage
2800 123 common/image.c Ramdisk unit name specified
2801 -124 common/image.c Can't get ramdisk subimage node offset
2802 125 common/image.c Got ramdisk subimage node offset
2803 -125 common/image.c Ramdisk subimage hash verification failed
2804 126 common/image.c Ramdisk subimage hash verification OK
2805 -126 common/image.c Ramdisk subimage for unsupported architecture
2806 127 common/image.c Architecture check OK
2807 -127 common/image.c Can't get ramdisk subimage data/size
2808 128 common/image.c Got ramdisk subimage data/size
2809 129 common/image.c Can't get ramdisk load address
2810 -129 common/image.c Got ramdisk load address
2812 -130 common/cmd_doc.c Incorrect FIT image format
2813 131 common/cmd_doc.c FIT image format OK
2815 -140 common/cmd_ide.c Incorrect FIT image format
2816 141 common/cmd_ide.c FIT image format OK
2818 -150 common/cmd_nand.c Incorrect FIT image format
2819 151 common/cmd_nand.c FIT image format OK
2821 - FIT image support:
2823 Enable support for the FIT uImage format.
2825 CONFIG_FIT_BEST_MATCH
2826 When no configuration is explicitly selected, default to the
2827 one whose fdt's compatibility field best matches that of
2828 U-Boot itself. A match is considered "best" if it matches the
2829 most specific compatibility entry of U-Boot's fdt's root node.
2830 The order of entries in the configuration's fdt is ignored.
2832 CONFIG_FIT_SIGNATURE
2833 This option enables signature verification of FIT uImages,
2834 using a hash signed and verified using RSA. See
2835 doc/uImage.FIT/signature.txt for more details.
2837 - Standalone program support:
2838 CONFIG_STANDALONE_LOAD_ADDR
2840 This option defines a board specific value for the
2841 address where standalone program gets loaded, thus
2842 overwriting the architecture dependent default
2845 - Frame Buffer Address:
2848 Define CONFIG_FB_ADDR if you want to use specific
2849 address for frame buffer. This is typically the case
2850 when using a graphics controller has separate video
2851 memory. U-Boot will then place the frame buffer at
2852 the given address instead of dynamically reserving it
2853 in system RAM by calling lcd_setmem(), which grabs
2854 the memory for the frame buffer depending on the
2855 configured panel size.
2857 Please see board_init_f function.
2859 - Automatic software updates via TFTP server
2861 CONFIG_UPDATE_TFTP_CNT_MAX
2862 CONFIG_UPDATE_TFTP_MSEC_MAX
2864 These options enable and control the auto-update feature;
2865 for a more detailed description refer to doc/README.update.
2867 - MTD Support (mtdparts command, UBI support)
2870 Adds the MTD device infrastructure from the Linux kernel.
2871 Needed for mtdparts command support.
2873 CONFIG_MTD_PARTITIONS
2875 Adds the MTD partitioning infrastructure from the Linux
2876 kernel. Needed for UBI support.
2881 Adds commands for interacting with MTD partitions formatted
2882 with the UBI flash translation layer
2884 Requires also defining CONFIG_RBTREE
2886 CONFIG_UBI_SILENCE_MSG
2888 Make the verbose messages from UBI stop printing. This leaves
2889 warnings and errors enabled.
2894 Adds commands for interacting with UBI volumes formatted as
2895 UBIFS. UBIFS is read-only in u-boot.
2897 Requires UBI support as well as CONFIG_LZO
2899 CONFIG_UBIFS_SILENCE_MSG
2901 Make the verbose messages from UBIFS stop printing. This leaves
2902 warnings and errors enabled.
2906 Enable building of SPL globally.
2909 LDSCRIPT for linking the SPL binary.
2911 CONFIG_SPL_MAX_FOOTPRINT
2912 Maximum size in memory allocated to the SPL, BSS included.
2913 When defined, the linker checks that the actual memory
2914 used by SPL from _start to __bss_end does not exceed it.
2915 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2916 must not be both defined at the same time.
2919 Maximum size of the SPL image (text, data, rodata, and
2920 linker lists sections), BSS excluded.
2921 When defined, the linker checks that the actual size does
2924 CONFIG_SPL_TEXT_BASE
2925 TEXT_BASE for linking the SPL binary.
2927 CONFIG_SPL_RELOC_TEXT_BASE
2928 Address to relocate to. If unspecified, this is equal to
2929 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2931 CONFIG_SPL_BSS_START_ADDR
2932 Link address for the BSS within the SPL binary.
2934 CONFIG_SPL_BSS_MAX_SIZE
2935 Maximum size in memory allocated to the SPL BSS.
2936 When defined, the linker checks that the actual memory used
2937 by SPL from __bss_start to __bss_end does not exceed it.
2938 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
2939 must not be both defined at the same time.
2942 Adress of the start of the stack SPL will use
2944 CONFIG_SPL_RELOC_STACK
2945 Adress of the start of the stack SPL will use after
2946 relocation. If unspecified, this is equal to
2949 CONFIG_SYS_SPL_MALLOC_START
2950 Starting address of the malloc pool used in SPL.
2952 CONFIG_SYS_SPL_MALLOC_SIZE
2953 The size of the malloc pool used in SPL.
2955 CONFIG_SPL_FRAMEWORK
2956 Enable the SPL framework under common/. This framework
2957 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2958 NAND loading of the Linux Kernel.
2960 CONFIG_SPL_DISPLAY_PRINT
2961 For ARM, enable an optional function to print more information
2962 about the running system.
2964 CONFIG_SPL_INIT_MINIMAL
2965 Arch init code should be built for a very small image
2967 CONFIG_SPL_LIBCOMMON_SUPPORT
2968 Support for common/libcommon.o in SPL binary
2970 CONFIG_SPL_LIBDISK_SUPPORT
2971 Support for disk/libdisk.o in SPL binary
2973 CONFIG_SPL_I2C_SUPPORT
2974 Support for drivers/i2c/libi2c.o in SPL binary
2976 CONFIG_SPL_GPIO_SUPPORT
2977 Support for drivers/gpio/libgpio.o in SPL binary
2979 CONFIG_SPL_MMC_SUPPORT
2980 Support for drivers/mmc/libmmc.o in SPL binary
2982 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
2983 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
2984 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
2985 Address, size and partition on the MMC to load U-Boot from
2986 when the MMC is being used in raw mode.
2988 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2989 Sector to load kernel uImage from when MMC is being
2990 used in raw mode (for Falcon mode)
2992 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2993 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2994 Sector and number of sectors to load kernel argument
2995 parameters from when MMC is being used in raw mode
2998 CONFIG_SPL_FAT_SUPPORT
2999 Support for fs/fat/libfat.o in SPL binary
3001 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
3002 Filename to read to load U-Boot when reading from FAT
3004 CONFIG_SPL_FAT_LOAD_KERNEL_NAME
3005 Filename to read to load kernel uImage when reading
3006 from FAT (for Falcon mode)
3008 CONFIG_SPL_FAT_LOAD_ARGS_NAME
3009 Filename to read to load kernel argument parameters
3010 when reading from FAT (for Falcon mode)
3012 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
3013 Set this for NAND SPL on PPC mpc83xx targets, so that
3014 start.S waits for the rest of the SPL to load before
3015 continuing (the hardware starts execution after just
3016 loading the first page rather than the full 4K).
3018 CONFIG_SPL_NAND_BASE
3019 Include nand_base.c in the SPL. Requires
3020 CONFIG_SPL_NAND_DRIVERS.
3022 CONFIG_SPL_NAND_DRIVERS
3023 SPL uses normal NAND drivers, not minimal drivers.
3026 Include standard software ECC in the SPL
3028 CONFIG_SPL_NAND_SIMPLE
3029 Support for NAND boot using simple NAND drivers that
3030 expose the cmd_ctrl() interface.
3032 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
3033 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
3034 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
3035 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
3036 CONFIG_SYS_NAND_ECCBYTES
3037 Defines the size and behavior of the NAND that SPL uses
3040 CONFIG_SYS_NAND_U_BOOT_OFFS
3041 Location in NAND to read U-Boot from
3043 CONFIG_SYS_NAND_U_BOOT_DST
3044 Location in memory to load U-Boot to
3046 CONFIG_SYS_NAND_U_BOOT_SIZE
3047 Size of image to load
3049 CONFIG_SYS_NAND_U_BOOT_START
3050 Entry point in loaded image to jump to
3052 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
3053 Define this if you need to first read the OOB and then the
3054 data. This is used for example on davinci plattforms.
3056 CONFIG_SPL_OMAP3_ID_NAND
3057 Support for an OMAP3-specific set of functions to return the
3058 ID and MFR of the first attached NAND chip, if present.
3060 CONFIG_SPL_SERIAL_SUPPORT
3061 Support for drivers/serial/libserial.o in SPL binary
3063 CONFIG_SPL_SPI_FLASH_SUPPORT
3064 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
3066 CONFIG_SPL_SPI_SUPPORT
3067 Support for drivers/spi/libspi.o in SPL binary
3069 CONFIG_SPL_RAM_DEVICE
3070 Support for running image already present in ram, in SPL binary
3072 CONFIG_SPL_LIBGENERIC_SUPPORT
3073 Support for lib/libgeneric.o in SPL binary
3075 CONFIG_SPL_ENV_SUPPORT
3076 Support for the environment operating in SPL binary
3078 CONFIG_SPL_NET_SUPPORT
3079 Support for the net/libnet.o in SPL binary.
3080 It conflicts with SPL env from storage medium specified by
3081 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE
3084 Image offset to which the SPL should be padded before appending
3085 the SPL payload. By default, this is defined as
3086 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
3087 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
3088 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
3091 Final target image containing SPL and payload. Some SPLs
3092 use an arch-specific makefile fragment instead, for
3093 example if more than one image needs to be produced.
3095 CONFIG_FIT_SPL_PRINT
3096 Printing information about a FIT image adds quite a bit of
3097 code to SPL. So this is normally disabled in SPL. Use this
3098 option to re-enable it. This will affect the output of the
3099 bootm command when booting a FIT image.
3104 [so far only for SMDK2400 boards]
3106 - Modem support enable:
3107 CONFIG_MODEM_SUPPORT
3109 - RTS/CTS Flow control enable:
3112 - Modem debug support:
3113 CONFIG_MODEM_SUPPORT_DEBUG
3115 Enables debugging stuff (char screen[1024], dbg())
3116 for modem support. Useful only with BDI2000.
3118 - Interrupt support (PPC):
3120 There are common interrupt_init() and timer_interrupt()
3121 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
3122 for CPU specific initialization. interrupt_init_cpu()
3123 should set decrementer_count to appropriate value. If
3124 CPU resets decrementer automatically after interrupt
3125 (ppc4xx) it should set decrementer_count to zero.
3126 timer_interrupt() calls timer_interrupt_cpu() for CPU
3127 specific handling. If board has watchdog / status_led
3128 / other_activity_monitor it works automatically from
3129 general timer_interrupt().
3133 In the target system modem support is enabled when a
3134 specific key (key combination) is pressed during
3135 power-on. Otherwise U-Boot will boot normally
3136 (autoboot). The key_pressed() function is called from
3137 board_init(). Currently key_pressed() is a dummy
3138 function, returning 1 and thus enabling modem
3141 If there are no modem init strings in the
3142 environment, U-Boot proceed to autoboot; the
3143 previous output (banner, info printfs) will be
3146 See also: doc/README.Modem
3148 Board initialization settings:
3149 ------------------------------
3151 During Initialization u-boot calls a number of board specific functions
3152 to allow the preparation of board specific prerequisites, e.g. pin setup
3153 before drivers are initialized. To enable these callbacks the
3154 following configuration macros have to be defined. Currently this is
3155 architecture specific, so please check arch/your_architecture/lib/board.c
3156 typically in board_init_f() and board_init_r().
3158 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
3159 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
3160 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
3161 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
3163 Configuration Settings:
3164 -----------------------
3166 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
3167 undefine this when you're short of memory.
3169 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
3170 width of the commands listed in the 'help' command output.
3172 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
3173 prompt for user input.
3175 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
3177 - CONFIG_SYS_PBSIZE: Buffer size for Console output
3179 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
3181 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
3182 the application (usually a Linux kernel) when it is
3185 - CONFIG_SYS_BAUDRATE_TABLE:
3186 List of legal baudrate settings for this board.
3188 - CONFIG_SYS_CONSOLE_INFO_QUIET
3189 Suppress display of console information at boot.
3191 - CONFIG_SYS_CONSOLE_IS_IN_ENV
3192 If the board specific function
3193 extern int overwrite_console (void);
3194 returns 1, the stdin, stderr and stdout are switched to the
3195 serial port, else the settings in the environment are used.
3197 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
3198 Enable the call to overwrite_console().
3200 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
3201 Enable overwrite of previous console environment settings.
3203 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
3204 Begin and End addresses of the area used by the
3207 - CONFIG_SYS_ALT_MEMTEST:
3208 Enable an alternate, more extensive memory test.
3210 - CONFIG_SYS_MEMTEST_SCRATCH:
3211 Scratch address used by the alternate memory test
3212 You only need to set this if address zero isn't writeable
3214 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
3215 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
3216 this specified memory area will get subtracted from the top
3217 (end) of RAM and won't get "touched" at all by U-Boot. By
3218 fixing up gd->ram_size the Linux kernel should gets passed
3219 the now "corrected" memory size and won't touch it either.
3220 This should work for arch/ppc and arch/powerpc. Only Linux
3221 board ports in arch/powerpc with bootwrapper support that
3222 recalculate the memory size from the SDRAM controller setup
3223 will have to get fixed in Linux additionally.
3225 This option can be used as a workaround for the 440EPx/GRx
3226 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
3229 WARNING: Please make sure that this value is a multiple of
3230 the Linux page size (normally 4k). If this is not the case,
3231 then the end address of the Linux memory will be located at a
3232 non page size aligned address and this could cause major
3235 - CONFIG_SYS_LOADS_BAUD_CHANGE:
3236 Enable temporary baudrate change while serial download
3238 - CONFIG_SYS_SDRAM_BASE:
3239 Physical start address of SDRAM. _Must_ be 0 here.
3241 - CONFIG_SYS_MBIO_BASE:
3242 Physical start address of Motherboard I/O (if using a
3245 - CONFIG_SYS_FLASH_BASE:
3246 Physical start address of Flash memory.
3248 - CONFIG_SYS_MONITOR_BASE:
3249 Physical start address of boot monitor code (set by
3250 make config files to be same as the text base address
3251 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
3252 CONFIG_SYS_FLASH_BASE when booting from flash.
3254 - CONFIG_SYS_MONITOR_LEN:
3255 Size of memory reserved for monitor code, used to
3256 determine _at_compile_time_ (!) if the environment is
3257 embedded within the U-Boot image, or in a separate
3260 - CONFIG_SYS_MALLOC_LEN:
3261 Size of DRAM reserved for malloc() use.
3263 - CONFIG_SYS_BOOTM_LEN:
3264 Normally compressed uImages are limited to an
3265 uncompressed size of 8 MBytes. If this is not enough,
3266 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3267 to adjust this setting to your needs.
3269 - CONFIG_SYS_BOOTMAPSZ:
3270 Maximum size of memory mapped by the startup code of
3271 the Linux kernel; all data that must be processed by
3272 the Linux kernel (bd_info, boot arguments, FDT blob if
3273 used) must be put below this limit, unless "bootm_low"
3274 enviroment variable is defined and non-zero. In such case
3275 all data for the Linux kernel must be between "bootm_low"
3276 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3277 variable "bootm_mapsize" will override the value of
3278 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3279 then the value in "bootm_size" will be used instead.
3281 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3282 Enable initrd_high functionality. If defined then the
3283 initrd_high feature is enabled and the bootm ramdisk subcommand
3286 - CONFIG_SYS_BOOT_GET_CMDLINE:
3287 Enables allocating and saving kernel cmdline in space between
3288 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3290 - CONFIG_SYS_BOOT_GET_KBD:
3291 Enables allocating and saving a kernel copy of the bd_info in
3292 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3294 - CONFIG_SYS_MAX_FLASH_BANKS:
3295 Max number of Flash memory banks
3297 - CONFIG_SYS_MAX_FLASH_SECT:
3298 Max number of sectors on a Flash chip
3300 - CONFIG_SYS_FLASH_ERASE_TOUT:
3301 Timeout for Flash erase operations (in ms)
3303 - CONFIG_SYS_FLASH_WRITE_TOUT:
3304 Timeout for Flash write operations (in ms)
3306 - CONFIG_SYS_FLASH_LOCK_TOUT
3307 Timeout for Flash set sector lock bit operation (in ms)
3309 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3310 Timeout for Flash clear lock bits operation (in ms)
3312 - CONFIG_SYS_FLASH_PROTECTION
3313 If defined, hardware flash sectors protection is used
3314 instead of U-Boot software protection.
3316 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3318 Enable TFTP transfers directly to flash memory;
3319 without this option such a download has to be
3320 performed in two steps: (1) download to RAM, and (2)
3321 copy from RAM to flash.
3323 The two-step approach is usually more reliable, since
3324 you can check if the download worked before you erase
3325 the flash, but in some situations (when system RAM is
3326 too limited to allow for a temporary copy of the
3327 downloaded image) this option may be very useful.
3329 - CONFIG_SYS_FLASH_CFI:
3330 Define if the flash driver uses extra elements in the
3331 common flash structure for storing flash geometry.
3333 - CONFIG_FLASH_CFI_DRIVER
3334 This option also enables the building of the cfi_flash driver
3335 in the drivers directory
3337 - CONFIG_FLASH_CFI_MTD
3338 This option enables the building of the cfi_mtd driver
3339 in the drivers directory. The driver exports CFI flash
3342 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3343 Use buffered writes to flash.
3345 - CONFIG_FLASH_SPANSION_S29WS_N
3346 s29ws-n MirrorBit flash has non-standard addresses for buffered
3349 - CONFIG_SYS_FLASH_QUIET_TEST
3350 If this option is defined, the common CFI flash doesn't
3351 print it's warning upon not recognized FLASH banks. This
3352 is useful, if some of the configured banks are only
3353 optionally available.
3355 - CONFIG_FLASH_SHOW_PROGRESS
3356 If defined (must be an integer), print out countdown
3357 digits and dots. Recommended value: 45 (9..1) for 80
3358 column displays, 15 (3..1) for 40 column displays.
3360 - CONFIG_FLASH_VERIFY
3361 If defined, the content of the flash (destination) is compared
3362 against the source after the write operation. An error message
3363 will be printed when the contents are not identical.
3364 Please note that this option is useless in nearly all cases,
3365 since such flash programming errors usually are detected earlier
3366 while unprotecting/erasing/programming. Please only enable
3367 this option if you really know what you are doing.
3369 - CONFIG_SYS_RX_ETH_BUFFER:
3370 Defines the number of Ethernet receive buffers. On some
3371 Ethernet controllers it is recommended to set this value
3372 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3373 buffers can be full shortly after enabling the interface
3374 on high Ethernet traffic.
3375 Defaults to 4 if not defined.
3377 - CONFIG_ENV_MAX_ENTRIES
3379 Maximum number of entries in the hash table that is used
3380 internally to store the environment settings. The default
3381 setting is supposed to be generous and should work in most
3382 cases. This setting can be used to tune behaviour; see
3383 lib/hashtable.c for details.
3385 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3386 - CONFIG_ENV_FLAGS_LIST_STATIC
3387 Enable validation of the values given to enviroment variables when
3388 calling env set. Variables can be restricted to only decimal,
3389 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
3390 the variables can also be restricted to IP address or MAC address.
3392 The format of the list is:
3393 type_attribute = [s|d|x|b|i|m]
3394 access_atribute = [a|r|o|c]
3395 attributes = type_attribute[access_atribute]
3396 entry = variable_name[:attributes]
3399 The type attributes are:
3400 s - String (default)
3403 b - Boolean ([1yYtT|0nNfF])
3407 The access attributes are:
3413 - CONFIG_ENV_FLAGS_LIST_DEFAULT
3414 Define this to a list (string) to define the ".flags"
3415 envirnoment variable in the default or embedded environment.
3417 - CONFIG_ENV_FLAGS_LIST_STATIC
3418 Define this to a list (string) to define validation that
3419 should be done if an entry is not found in the ".flags"
3420 environment variable. To override a setting in the static
3421 list, simply add an entry for the same variable name to the
3424 - CONFIG_ENV_ACCESS_IGNORE_FORCE
3425 If defined, don't allow the -f switch to env set override variable
3428 - CONFIG_SYS_GENERIC_BOARD
3429 This selects the architecture-generic board system instead of the
3430 architecture-specific board files. It is intended to move boards
3431 to this new framework over time. Defining this will disable the
3432 arch/foo/lib/board.c file and use common/board_f.c and
3433 common/board_r.c instead. To use this option your architecture
3434 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
3435 its config.mk file). If you find problems enabling this option on
3436 your board please report the problem and send patches!
3438 - CONFIG_SYS_SYM_OFFSETS
3439 This is set by architectures that use offsets for link symbols
3440 instead of absolute values. So bss_start is obtained using an
3441 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
3442 directly. You should not need to touch this setting.
3444 - CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only)
3445 This is set by OMAP boards for the max time that reset should
3446 be asserted. See doc/README.omap-reset-time for details on how
3447 the value can be calulated on a given board.
3449 The following definitions that deal with the placement and management
3450 of environment data (variable area); in general, we support the
3451 following configurations:
3453 - CONFIG_BUILD_ENVCRC:
3455 Builds up envcrc with the target environment so that external utils
3456 may easily extract it and embed it in final U-Boot images.
3458 - CONFIG_ENV_IS_IN_FLASH:
3460 Define this if the environment is in flash memory.
3462 a) The environment occupies one whole flash sector, which is
3463 "embedded" in the text segment with the U-Boot code. This
3464 happens usually with "bottom boot sector" or "top boot
3465 sector" type flash chips, which have several smaller
3466 sectors at the start or the end. For instance, such a
3467 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3468 such a case you would place the environment in one of the
3469 4 kB sectors - with U-Boot code before and after it. With
3470 "top boot sector" type flash chips, you would put the
3471 environment in one of the last sectors, leaving a gap
3472 between U-Boot and the environment.
3474 - CONFIG_ENV_OFFSET:
3476 Offset of environment data (variable area) to the
3477 beginning of flash memory; for instance, with bottom boot
3478 type flash chips the second sector can be used: the offset
3479 for this sector is given here.
3481 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3485 This is just another way to specify the start address of
3486 the flash sector containing the environment (instead of
3489 - CONFIG_ENV_SECT_SIZE:
3491 Size of the sector containing the environment.
3494 b) Sometimes flash chips have few, equal sized, BIG sectors.
3495 In such a case you don't want to spend a whole sector for
3500 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3501 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3502 of this flash sector for the environment. This saves
3503 memory for the RAM copy of the environment.
3505 It may also save flash memory if you decide to use this
3506 when your environment is "embedded" within U-Boot code,
3507 since then the remainder of the flash sector could be used
3508 for U-Boot code. It should be pointed out that this is
3509 STRONGLY DISCOURAGED from a robustness point of view:
3510 updating the environment in flash makes it always
3511 necessary to erase the WHOLE sector. If something goes
3512 wrong before the contents has been restored from a copy in
3513 RAM, your target system will be dead.
3515 - CONFIG_ENV_ADDR_REDUND
3516 CONFIG_ENV_SIZE_REDUND
3518 These settings describe a second storage area used to hold
3519 a redundant copy of the environment data, so that there is
3520 a valid backup copy in case there is a power failure during
3521 a "saveenv" operation.
3523 BE CAREFUL! Any changes to the flash layout, and some changes to the
3524 source code will make it necessary to adapt <board>/u-boot.lds*
3528 - CONFIG_ENV_IS_IN_NVRAM:
3530 Define this if you have some non-volatile memory device
3531 (NVRAM, battery buffered SRAM) which you want to use for the
3537 These two #defines are used to determine the memory area you
3538 want to use for environment. It is assumed that this memory
3539 can just be read and written to, without any special
3542 BE CAREFUL! The first access to the environment happens quite early
3543 in U-Boot initalization (when we try to get the setting of for the
3544 console baudrate). You *MUST* have mapped your NVRAM area then, or
3547 Please note that even with NVRAM we still use a copy of the
3548 environment in RAM: we could work on NVRAM directly, but we want to
3549 keep settings there always unmodified except somebody uses "saveenv"
3550 to save the current settings.
3553 - CONFIG_ENV_IS_IN_EEPROM:
3555 Use this if you have an EEPROM or similar serial access
3556 device and a driver for it.
3558 - CONFIG_ENV_OFFSET:
3561 These two #defines specify the offset and size of the
3562 environment area within the total memory of your EEPROM.
3564 - CONFIG_SYS_I2C_EEPROM_ADDR:
3565 If defined, specified the chip address of the EEPROM device.
3566 The default address is zero.
3568 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3569 If defined, the number of bits used to address bytes in a
3570 single page in the EEPROM device. A 64 byte page, for example
3571 would require six bits.
3573 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3574 If defined, the number of milliseconds to delay between
3575 page writes. The default is zero milliseconds.
3577 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3578 The length in bytes of the EEPROM memory array address. Note
3579 that this is NOT the chip address length!
3581 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3582 EEPROM chips that implement "address overflow" are ones
3583 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3584 address and the extra bits end up in the "chip address" bit
3585 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3588 Note that we consider the length of the address field to
3589 still be one byte because the extra address bits are hidden
3590 in the chip address.
3592 - CONFIG_SYS_EEPROM_SIZE:
3593 The size in bytes of the EEPROM device.
3595 - CONFIG_ENV_EEPROM_IS_ON_I2C
3596 define this, if you have I2C and SPI activated, and your
3597 EEPROM, which holds the environment, is on the I2C bus.
3599 - CONFIG_I2C_ENV_EEPROM_BUS
3600 if you have an Environment on an EEPROM reached over
3601 I2C muxes, you can define here, how to reach this
3602 EEPROM. For example:
3604 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
3606 EEPROM which holds the environment, is reached over
3607 a pca9547 i2c mux with address 0x70, channel 3.
3609 - CONFIG_ENV_IS_IN_DATAFLASH:
3611 Define this if you have a DataFlash memory device which you
3612 want to use for the environment.
3614 - CONFIG_ENV_OFFSET:
3618 These three #defines specify the offset and size of the
3619 environment area within the total memory of your DataFlash placed
3620 at the specified address.
3622 - CONFIG_ENV_IS_IN_REMOTE:
3624 Define this if you have a remote memory space which you
3625 want to use for the local device's environment.
3630 These two #defines specify the address and size of the
3631 environment area within the remote memory space. The
3632 local device can get the environment from remote memory
3633 space by SRIO or PCIE links.
3635 BE CAREFUL! For some special cases, the local device can not use
3636 "saveenv" command. For example, the local device will get the
3637 environment stored in a remote NOR flash by SRIO or PCIE link,
3638 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3640 - CONFIG_ENV_IS_IN_NAND:
3642 Define this if you have a NAND device which you want to use
3643 for the environment.
3645 - CONFIG_ENV_OFFSET:
3648 These two #defines specify the offset and size of the environment
3649 area within the first NAND device. CONFIG_ENV_OFFSET must be
3650 aligned to an erase block boundary.
3652 - CONFIG_ENV_OFFSET_REDUND (optional):
3654 This setting describes a second storage area of CONFIG_ENV_SIZE
3655 size used to hold a redundant copy of the environment data, so
3656 that there is a valid backup copy in case there is a power failure
3657 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3658 aligned to an erase block boundary.
3660 - CONFIG_ENV_RANGE (optional):
3662 Specifies the length of the region in which the environment
3663 can be written. This should be a multiple of the NAND device's
3664 block size. Specifying a range with more erase blocks than
3665 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3666 the range to be avoided.
3668 - CONFIG_ENV_OFFSET_OOB (optional):
3670 Enables support for dynamically retrieving the offset of the
3671 environment from block zero's out-of-band data. The
3672 "nand env.oob" command can be used to record this offset.
3673 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3674 using CONFIG_ENV_OFFSET_OOB.
3676 - CONFIG_NAND_ENV_DST
3678 Defines address in RAM to which the nand_spl code should copy the
3679 environment. If redundant environment is used, it will be copied to
3680 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3682 - CONFIG_ENV_IS_IN_UBI:
3684 Define this if you have an UBI volume that you want to use for the
3685 environment. This has the benefit of wear-leveling the environment
3686 accesses, which is important on NAND.
3688 - CONFIG_ENV_UBI_PART:
3690 Define this to a string that is the mtd partition containing the UBI.
3692 - CONFIG_ENV_UBI_VOLUME:
3694 Define this to the name of the volume that you want to store the
3697 - CONFIG_ENV_UBI_VOLUME_REDUND:
3699 Define this to the name of another volume to store a second copy of
3700 the environment in. This will enable redundant environments in UBI.
3701 It is assumed that both volumes are in the same MTD partition.
3703 - CONFIG_UBI_SILENCE_MSG
3704 - CONFIG_UBIFS_SILENCE_MSG
3706 You will probably want to define these to avoid a really noisy system
3707 when storing the env in UBI.
3709 - CONFIG_ENV_IS_IN_MMC:
3711 Define this if you have an MMC device which you want to use for the
3714 - CONFIG_SYS_MMC_ENV_DEV:
3716 Specifies which MMC device the environment is stored in.
3718 - CONFIG_SYS_MMC_ENV_PART (optional):
3720 Specifies which MMC partition the environment is stored in. If not
3721 set, defaults to partition 0, the user area. Common values might be
3722 1 (first MMC boot partition), 2 (second MMC boot partition).
3724 - CONFIG_ENV_OFFSET:
3727 These two #defines specify the offset and size of the environment
3728 area within the specified MMC device.
3730 If offset is positive (the usual case), it is treated as relative to
3731 the start of the MMC partition. If offset is negative, it is treated
3732 as relative to the end of the MMC partition. This can be useful if
3733 your board may be fitted with different MMC devices, which have
3734 different sizes for the MMC partitions, and you always want the
3735 environment placed at the very end of the partition, to leave the
3736 maximum possible space before it, to store other data.
3738 These two values are in units of bytes, but must be aligned to an
3739 MMC sector boundary.
3741 - CONFIG_ENV_OFFSET_REDUND (optional):
3743 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
3744 hold a redundant copy of the environment data. This provides a
3745 valid backup copy in case the other copy is corrupted, e.g. due
3746 to a power failure during a "saveenv" operation.
3748 This value may also be positive or negative; this is handled in the
3749 same way as CONFIG_ENV_OFFSET.
3751 This value is also in units of bytes, but must also be aligned to
3752 an MMC sector boundary.
3754 - CONFIG_ENV_SIZE_REDUND (optional):
3756 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is
3757 set. If this value is set, it must be set to the same value as
3760 - CONFIG_SYS_SPI_INIT_OFFSET
3762 Defines offset to the initial SPI buffer area in DPRAM. The
3763 area is used at an early stage (ROM part) if the environment
3764 is configured to reside in the SPI EEPROM: We need a 520 byte
3765 scratch DPRAM area. It is used between the two initialization
3766 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3767 to be a good choice since it makes it far enough from the
3768 start of the data area as well as from the stack pointer.
3770 Please note that the environment is read-only until the monitor
3771 has been relocated to RAM and a RAM copy of the environment has been
3772 created; also, when using EEPROM you will have to use getenv_f()
3773 until then to read environment variables.
3775 The environment is protected by a CRC32 checksum. Before the monitor
3776 is relocated into RAM, as a result of a bad CRC you will be working
3777 with the compiled-in default environment - *silently*!!! [This is
3778 necessary, because the first environment variable we need is the
3779 "baudrate" setting for the console - if we have a bad CRC, we don't
3780 have any device yet where we could complain.]
3782 Note: once the monitor has been relocated, then it will complain if
3783 the default environment is used; a new CRC is computed as soon as you
3784 use the "saveenv" command to store a valid environment.
3786 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3787 Echo the inverted Ethernet link state to the fault LED.
3789 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3790 also needs to be defined.
3792 - CONFIG_SYS_FAULT_MII_ADDR:
3793 MII address of the PHY to check for the Ethernet link state.
3795 - CONFIG_NS16550_MIN_FUNCTIONS:
3796 Define this if you desire to only have use of the NS16550_init
3797 and NS16550_putc functions for the serial driver located at
3798 drivers/serial/ns16550.c. This option is useful for saving
3799 space for already greatly restricted images, including but not
3800 limited to NAND_SPL configurations.
3802 - CONFIG_DISPLAY_BOARDINFO
3803 Display information about the board that U-Boot is running on
3804 when U-Boot starts up. The board function checkboard() is called
3807 - CONFIG_DISPLAY_BOARDINFO_LATE
3808 Similar to the previous option, but display this information
3809 later, once stdio is running and output goes to the LCD, if
3812 Low Level (hardware related) configuration options:
3813 ---------------------------------------------------
3815 - CONFIG_SYS_CACHELINE_SIZE:
3816 Cache Line Size of the CPU.
3818 - CONFIG_SYS_DEFAULT_IMMR:
3819 Default address of the IMMR after system reset.
3821 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3822 and RPXsuper) to be able to adjust the position of
3823 the IMMR register after a reset.
3825 - CONFIG_SYS_CCSRBAR_DEFAULT:
3826 Default (power-on reset) physical address of CCSR on Freescale
3829 - CONFIG_SYS_CCSRBAR:
3830 Virtual address of CCSR. On a 32-bit build, this is typically
3831 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3833 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3834 for cross-platform code that uses that macro instead.
3836 - CONFIG_SYS_CCSRBAR_PHYS:
3837 Physical address of CCSR. CCSR can be relocated to a new
3838 physical address, if desired. In this case, this macro should
3839 be set to that address. Otherwise, it should be set to the
3840 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3841 is typically relocated on 36-bit builds. It is recommended
3842 that this macro be defined via the _HIGH and _LOW macros:
3844 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3845 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3847 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3848 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3849 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3850 used in assembly code, so it must not contain typecasts or
3851 integer size suffixes (e.g. "ULL").
3853 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3854 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3855 used in assembly code, so it must not contain typecasts or
3856 integer size suffixes (e.g. "ULL").
3858 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3859 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3860 forced to a value that ensures that CCSR is not relocated.
3862 - Floppy Disk Support:
3863 CONFIG_SYS_FDC_DRIVE_NUMBER
3865 the default drive number (default value 0)
3867 CONFIG_SYS_ISA_IO_STRIDE
3869 defines the spacing between FDC chipset registers
3872 CONFIG_SYS_ISA_IO_OFFSET
3874 defines the offset of register from address. It
3875 depends on which part of the data bus is connected to
3876 the FDC chipset. (default value 0)
3878 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3879 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3882 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3883 fdc_hw_init() is called at the beginning of the FDC
3884 setup. fdc_hw_init() must be provided by the board
3885 source code. It is used to make hardware dependant
3889 Most IDE controllers were designed to be connected with PCI
3890 interface. Only few of them were designed for AHB interface.
3891 When software is doing ATA command and data transfer to
3892 IDE devices through IDE-AHB controller, some additional
3893 registers accessing to these kind of IDE-AHB controller
3896 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3897 DO NOT CHANGE unless you know exactly what you're
3898 doing! (11-4) [MPC8xx/82xx systems only]
3900 - CONFIG_SYS_INIT_RAM_ADDR:
3902 Start address of memory area that can be used for
3903 initial data and stack; please note that this must be
3904 writable memory that is working WITHOUT special
3905 initialization, i. e. you CANNOT use normal RAM which
3906 will become available only after programming the
3907 memory controller and running certain initialization
3910 U-Boot uses the following memory types:
3911 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3912 - MPC824X: data cache
3913 - PPC4xx: data cache
3915 - CONFIG_SYS_GBL_DATA_OFFSET:
3917 Offset of the initial data structure in the memory
3918 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3919 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3920 data is located at the end of the available space
3921 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3922 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3923 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3924 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3927 On the MPC824X (or other systems that use the data
3928 cache for initial memory) the address chosen for
3929 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3930 point to an otherwise UNUSED address space between
3931 the top of RAM and the start of the PCI space.
3933 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3935 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3937 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3939 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3941 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3943 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3945 - CONFIG_SYS_OR_TIMING_SDRAM:
3948 - CONFIG_SYS_MAMR_PTA:
3949 periodic timer for refresh
3951 - CONFIG_SYS_DER: Debug Event Register (37-47)
3953 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3954 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3955 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3956 CONFIG_SYS_BR1_PRELIM:
3957 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3959 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3960 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3961 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3962 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3964 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3965 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3966 Machine Mode Register and Memory Periodic Timer
3967 Prescaler definitions (SDRAM timing)
3969 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3970 enable I2C microcode relocation patch (MPC8xx);
3971 define relocation offset in DPRAM [DSP2]
3973 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3974 enable SMC microcode relocation patch (MPC8xx);
3975 define relocation offset in DPRAM [SMC1]
3977 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3978 enable SPI microcode relocation patch (MPC8xx);
3979 define relocation offset in DPRAM [SCC4]
3981 - CONFIG_SYS_USE_OSCCLK:
3982 Use OSCM clock mode on MBX8xx board. Be careful,
3983 wrong setting might damage your board. Read
3984 doc/README.MBX before setting this variable!
3986 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3987 Offset of the bootmode word in DPRAM used by post
3988 (Power On Self Tests). This definition overrides
3989 #define'd default value in commproc.h resp.
3992 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3993 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3994 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3995 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3996 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3997 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3998 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3999 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
4000 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
4002 - CONFIG_PCI_DISABLE_PCIE:
4003 Disable PCI-Express on systems where it is supported but not
4006 - CONFIG_PCI_ENUM_ONLY
4007 Only scan through and get the devices on the busses.
4008 Don't do any setup work, presumably because someone or
4009 something has already done it, and we don't need to do it
4010 a second time. Useful for platforms that are pre-booted
4011 by coreboot or similar.
4013 - CONFIG_PCI_INDIRECT_BRIDGE:
4014 Enable support for indirect PCI bridges.
4017 Chip has SRIO or not
4020 Board has SRIO 1 port available
4023 Board has SRIO 2 port available
4025 - CONFIG_SRIO_PCIE_BOOT_MASTER
4026 Board can support master function for Boot from SRIO and PCIE
4028 - CONFIG_SYS_SRIOn_MEM_VIRT:
4029 Virtual Address of SRIO port 'n' memory region
4031 - CONFIG_SYS_SRIOn_MEM_PHYS:
4032 Physical Address of SRIO port 'n' memory region
4034 - CONFIG_SYS_SRIOn_MEM_SIZE:
4035 Size of SRIO port 'n' memory region
4037 - CONFIG_SYS_NAND_BUSWIDTH_16BIT
4038 Defined to tell the NAND controller that the NAND chip is using
4040 Not all NAND drivers use this symbol.
4041 Example of drivers that use it:
4042 - drivers/mtd/nand/ndfc.c
4043 - drivers/mtd/nand/mxc_nand.c
4045 - CONFIG_SYS_NDFC_EBC0_CFG
4046 Sets the EBC0_CFG register for the NDFC. If not defined
4047 a default value will be used.
4050 Get DDR timing information from an I2C EEPROM. Common
4051 with pluggable memory modules such as SODIMMs
4054 I2C address of the SPD EEPROM
4056 - CONFIG_SYS_SPD_BUS_NUM
4057 If SPD EEPROM is on an I2C bus other than the first
4058 one, specify here. Note that the value must resolve
4059 to something your driver can deal with.
4061 - CONFIG_SYS_DDR_RAW_TIMING
4062 Get DDR timing information from other than SPD. Common with
4063 soldered DDR chips onboard without SPD. DDR raw timing
4064 parameters are extracted from datasheet and hard-coded into
4065 header files or board specific files.
4067 - CONFIG_FSL_DDR_INTERACTIVE
4068 Enable interactive DDR debugging. See doc/README.fsl-ddr.
4070 - CONFIG_SYS_83XX_DDR_USES_CS0
4071 Only for 83xx systems. If specified, then DDR should
4072 be configured using CS0 and CS1 instead of CS2 and CS3.
4074 - CONFIG_ETHER_ON_FEC[12]
4075 Define to enable FEC[12] on a 8xx series processor.
4077 - CONFIG_FEC[12]_PHY
4078 Define to the hardcoded PHY address which corresponds
4079 to the given FEC; i. e.
4080 #define CONFIG_FEC1_PHY 4
4081 means that the PHY with address 4 is connected to FEC1
4083 When set to -1, means to probe for first available.
4085 - CONFIG_FEC[12]_PHY_NORXERR
4086 The PHY does not have a RXERR line (RMII only).
4087 (so program the FEC to ignore it).
4090 Enable RMII mode for all FECs.
4091 Note that this is a global option, we can't
4092 have one FEC in standard MII mode and another in RMII mode.
4094 - CONFIG_CRC32_VERIFY
4095 Add a verify option to the crc32 command.
4098 => crc32 -v <address> <count> <crc32>
4100 Where address/count indicate a memory area
4101 and crc32 is the correct crc32 which the
4105 Add the "loopw" memory command. This only takes effect if
4106 the memory commands are activated globally (CONFIG_CMD_MEM).
4109 Add the "mdc" and "mwc" memory commands. These are cyclic
4114 This command will print 4 bytes (10,11,12,13) each 500 ms.
4116 => mwc.l 100 12345678 10
4117 This command will write 12345678 to address 100 all 10 ms.
4119 This only takes effect if the memory commands are activated
4120 globally (CONFIG_CMD_MEM).
4122 - CONFIG_SKIP_LOWLEVEL_INIT
4123 [ARM, NDS32, MIPS only] If this variable is defined, then certain
4124 low level initializations (like setting up the memory
4125 controller) are omitted and/or U-Boot does not
4126 relocate itself into RAM.
4128 Normally this variable MUST NOT be defined. The only
4129 exception is when U-Boot is loaded (to RAM) by some
4130 other boot loader or by a debugger which performs
4131 these initializations itself.
4134 Modifies the behaviour of start.S when compiling a loader
4135 that is executed before the actual U-Boot. E.g. when
4136 compiling a NAND SPL.
4138 - CONFIG_SYS_MPC85XX_NO_RESETVEC
4139 Only for 85xx systems. If this variable is specified, the section
4140 .resetvec is not kept and the section .bootpg is placed in the
4141 previous 4k of the .text section.
4143 - CONFIG_ARCH_MAP_SYSMEM
4144 Generally U-Boot (and in particular the md command) uses
4145 effective address. It is therefore not necessary to regard
4146 U-Boot address as virtual addresses that need to be translated
4147 to physical addresses. However, sandbox requires this, since
4148 it maintains its own little RAM buffer which contains all
4149 addressable memory. This option causes some memory accesses
4150 to be mapped through map_sysmem() / unmap_sysmem().
4152 - CONFIG_USE_ARCH_MEMCPY
4153 CONFIG_USE_ARCH_MEMSET
4154 If these options are used a optimized version of memcpy/memset will
4155 be used if available. These functions may be faster under some
4156 conditions but may increase the binary size.
4158 - CONFIG_X86_RESET_VECTOR
4159 If defined, the x86 reset vector code is included. This is not
4160 needed when U-Boot is running from Coreboot.
4163 Defines the MPU clock speed (in MHz).
4165 NOTE : currently only supported on AM335x platforms.
4167 Freescale QE/FMAN Firmware Support:
4168 -----------------------------------
4170 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
4171 loading of "firmware", which is encoded in the QE firmware binary format.
4172 This firmware often needs to be loaded during U-Boot booting, so macros
4173 are used to identify the storage device (NOR flash, SPI, etc) and the address
4176 - CONFIG_SYS_QE_FMAN_FW_ADDR
4177 The address in the storage device where the firmware is located. The
4178 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
4181 - CONFIG_SYS_QE_FMAN_FW_LENGTH
4182 The maximum possible size of the firmware. The firmware binary format
4183 has a field that specifies the actual size of the firmware, but it
4184 might not be possible to read any part of the firmware unless some
4185 local storage is allocated to hold the entire firmware first.
4187 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
4188 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
4189 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
4190 virtual address in NOR flash.
4192 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
4193 Specifies that QE/FMAN firmware is located in NAND flash.
4194 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
4196 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
4197 Specifies that QE/FMAN firmware is located on the primary SD/MMC
4198 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4200 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
4201 Specifies that QE/FMAN firmware is located on the primary SPI
4202 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
4204 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
4205 Specifies that QE/FMAN firmware is located in the remote (master)
4206 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
4207 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
4208 window->master inbound window->master LAW->the ucode address in
4209 master's memory space.
4211 Building the Software:
4212 ======================
4214 Building U-Boot has been tested in several native build environments
4215 and in many different cross environments. Of course we cannot support
4216 all possibly existing versions of cross development tools in all
4217 (potentially obsolete) versions. In case of tool chain problems we
4218 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
4219 which is extensively used to build and test U-Boot.
4221 If you are not using a native environment, it is assumed that you
4222 have GNU cross compiling tools available in your path. In this case,
4223 you must set the environment variable CROSS_COMPILE in your shell.
4224 Note that no changes to the Makefile or any other source files are
4225 necessary. For example using the ELDK on a 4xx CPU, please enter:
4227 $ CROSS_COMPILE=ppc_4xx-
4228 $ export CROSS_COMPILE
4230 Note: If you wish to generate Windows versions of the utilities in
4231 the tools directory you can use the MinGW toolchain
4232 (http://www.mingw.org). Set your HOST tools to the MinGW
4233 toolchain and execute 'make tools'. For example:
4235 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
4237 Binaries such as tools/mkimage.exe will be created which can
4238 be executed on computers running Windows.
4240 U-Boot is intended to be simple to build. After installing the
4241 sources you must configure U-Boot for one specific board type. This
4246 where "NAME_config" is the name of one of the existing configu-
4247 rations; see boards.cfg for supported names.
4249 Note: for some board special configuration names may exist; check if
4250 additional information is available from the board vendor; for
4251 instance, the TQM823L systems are available without (standard)
4252 or with LCD support. You can select such additional "features"
4253 when choosing the configuration, i. e.
4256 - will configure for a plain TQM823L, i. e. no LCD support
4258 make TQM823L_LCD_config
4259 - will configure for a TQM823L with U-Boot console on LCD
4264 Finally, type "make all", and you should get some working U-Boot
4265 images ready for download to / installation on your system:
4267 - "u-boot.bin" is a raw binary image
4268 - "u-boot" is an image in ELF binary format
4269 - "u-boot.srec" is in Motorola S-Record format
4271 By default the build is performed locally and the objects are saved
4272 in the source directory. One of the two methods can be used to change
4273 this behavior and build U-Boot to some external directory:
4275 1. Add O= to the make command line invocations:
4277 make O=/tmp/build distclean
4278 make O=/tmp/build NAME_config
4279 make O=/tmp/build all
4281 2. Set environment variable BUILD_DIR to point to the desired location:
4283 export BUILD_DIR=/tmp/build
4288 Note that the command line "O=" setting overrides the BUILD_DIR environment
4292 Please be aware that the Makefiles assume you are using GNU make, so
4293 for instance on NetBSD you might need to use "gmake" instead of
4297 If the system board that you have is not listed, then you will need
4298 to port U-Boot to your hardware platform. To do this, follow these
4301 1. Add a new configuration option for your board to the toplevel
4302 "boards.cfg" file, using the existing entries as examples.
4303 Follow the instructions there to keep the boards in order.
4304 2. Create a new directory to hold your board specific code. Add any
4305 files you need. In your board directory, you will need at least
4306 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
4307 3. Create a new configuration file "include/configs/<board>.h" for
4309 3. If you're porting U-Boot to a new CPU, then also create a new
4310 directory to hold your CPU specific code. Add any files you need.
4311 4. Run "make <board>_config" with your new name.
4312 5. Type "make", and you should get a working "u-boot.srec" file
4313 to be installed on your target system.
4314 6. Debug and solve any problems that might arise.
4315 [Of course, this last step is much harder than it sounds.]
4318 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
4319 ==============================================================
4321 If you have modified U-Boot sources (for instance added a new board
4322 or support for new devices, a new CPU, etc.) you are expected to
4323 provide feedback to the other developers. The feedback normally takes
4324 the form of a "patch", i. e. a context diff against a certain (latest
4325 official or latest in the git repository) version of U-Boot sources.
4327 But before you submit such a patch, please verify that your modifi-
4328 cation did not break existing code. At least make sure that *ALL* of
4329 the supported boards compile WITHOUT ANY compiler warnings. To do so,
4330 just run the "MAKEALL" script, which will configure and build U-Boot
4331 for ALL supported system. Be warned, this will take a while. You can
4332 select which (cross) compiler to use by passing a `CROSS_COMPILE'
4333 environment variable to the script, i. e. to use the ELDK cross tools
4336 CROSS_COMPILE=ppc_8xx- MAKEALL
4338 or to build on a native PowerPC system you can type
4340 CROSS_COMPILE=' ' MAKEALL
4342 When using the MAKEALL script, the default behaviour is to build
4343 U-Boot in the source directory. This location can be changed by
4344 setting the BUILD_DIR environment variable. Also, for each target
4345 built, the MAKEALL script saves two log files (<target>.ERR and
4346 <target>.MAKEALL) in the <source dir>/LOG directory. This default
4347 location can be changed by setting the MAKEALL_LOGDIR environment
4348 variable. For example:
4350 export BUILD_DIR=/tmp/build
4351 export MAKEALL_LOGDIR=/tmp/log
4352 CROSS_COMPILE=ppc_8xx- MAKEALL
4354 With the above settings build objects are saved in the /tmp/build,
4355 log files are saved in the /tmp/log and the source tree remains clean
4356 during the whole build process.
4359 See also "U-Boot Porting Guide" below.
4362 Monitor Commands - Overview:
4363 ============================
4365 go - start application at address 'addr'
4366 run - run commands in an environment variable
4367 bootm - boot application image from memory
4368 bootp - boot image via network using BootP/TFTP protocol
4369 bootz - boot zImage from memory
4370 tftpboot- boot image via network using TFTP protocol
4371 and env variables "ipaddr" and "serverip"
4372 (and eventually "gatewayip")
4373 tftpput - upload a file via network using TFTP protocol
4374 rarpboot- boot image via network using RARP/TFTP protocol
4375 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
4376 loads - load S-Record file over serial line
4377 loadb - load binary file over serial line (kermit mode)
4379 mm - memory modify (auto-incrementing)
4380 nm - memory modify (constant address)
4381 mw - memory write (fill)
4383 cmp - memory compare
4384 crc32 - checksum calculation
4385 i2c - I2C sub-system
4386 sspi - SPI utility commands
4387 base - print or set address offset
4388 printenv- print environment variables
4389 setenv - set environment variables
4390 saveenv - save environment variables to persistent storage
4391 protect - enable or disable FLASH write protection
4392 erase - erase FLASH memory
4393 flinfo - print FLASH memory information
4394 nand - NAND memory operations (see doc/README.nand)
4395 bdinfo - print Board Info structure
4396 iminfo - print header information for application image
4397 coninfo - print console devices and informations
4398 ide - IDE sub-system
4399 loop - infinite loop on address range
4400 loopw - infinite write loop on address range
4401 mtest - simple RAM test
4402 icache - enable or disable instruction cache
4403 dcache - enable or disable data cache
4404 reset - Perform RESET of the CPU
4405 echo - echo args to console
4406 version - print monitor version
4407 help - print online help
4408 ? - alias for 'help'
4411 Monitor Commands - Detailed Description:
4412 ========================================
4416 For now: just type "help <command>".
4419 Environment Variables:
4420 ======================
4422 U-Boot supports user configuration using Environment Variables which
4423 can be made persistent by saving to Flash memory.
4425 Environment Variables are set using "setenv", printed using
4426 "printenv", and saved to Flash using "saveenv". Using "setenv"
4427 without a value can be used to delete a variable from the
4428 environment. As long as you don't save the environment you are
4429 working with an in-memory copy. In case the Flash area containing the
4430 environment is erased by accident, a default environment is provided.
4432 Some configuration options can be set using Environment Variables.
4434 List of environment variables (most likely not complete):
4436 baudrate - see CONFIG_BAUDRATE
4438 bootdelay - see CONFIG_BOOTDELAY
4440 bootcmd - see CONFIG_BOOTCOMMAND
4442 bootargs - Boot arguments when booting an RTOS image
4444 bootfile - Name of the image to load with TFTP
4446 bootm_low - Memory range available for image processing in the bootm
4447 command can be restricted. This variable is given as
4448 a hexadecimal number and defines lowest address allowed
4449 for use by the bootm command. See also "bootm_size"
4450 environment variable. Address defined by "bootm_low" is
4451 also the base of the initial memory mapping for the Linux
4452 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4455 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4456 This variable is given as a hexadecimal number and it
4457 defines the size of the memory region starting at base
4458 address bootm_low that is accessible by the Linux kernel
4459 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4460 as the default value if it is defined, and bootm_size is
4463 bootm_size - Memory range available for image processing in the bootm
4464 command can be restricted. This variable is given as
4465 a hexadecimal number and defines the size of the region
4466 allowed for use by the bootm command. See also "bootm_low"
4467 environment variable.
4469 updatefile - Location of the software update file on a TFTP server, used
4470 by the automatic software update feature. Please refer to
4471 documentation in doc/README.update for more details.
4473 autoload - if set to "no" (any string beginning with 'n'),
4474 "bootp" will just load perform a lookup of the
4475 configuration from the BOOTP server, but not try to
4476 load any image using TFTP
4478 autostart - if set to "yes", an image loaded using the "bootp",
4479 "rarpboot", "tftpboot" or "diskboot" commands will
4480 be automatically started (by internally calling
4483 If set to "no", a standalone image passed to the
4484 "bootm" command will be copied to the load address
4485 (and eventually uncompressed), but NOT be started.
4486 This can be used to load and uncompress arbitrary
4489 fdt_high - if set this restricts the maximum address that the
4490 flattened device tree will be copied into upon boot.
4491 For example, if you have a system with 1 GB memory
4492 at physical address 0x10000000, while Linux kernel
4493 only recognizes the first 704 MB as low memory, you
4494 may need to set fdt_high as 0x3C000000 to have the
4495 device tree blob be copied to the maximum address
4496 of the 704 MB low memory, so that Linux kernel can
4497 access it during the boot procedure.
4499 If this is set to the special value 0xFFFFFFFF then
4500 the fdt will not be copied at all on boot. For this
4501 to work it must reside in writable memory, have
4502 sufficient padding on the end of it for u-boot to
4503 add the information it needs into it, and the memory
4504 must be accessible by the kernel.
4506 fdtcontroladdr- if set this is the address of the control flattened
4507 device tree used by U-Boot when CONFIG_OF_CONTROL is
4510 i2cfast - (PPC405GP|PPC405EP only)
4511 if set to 'y' configures Linux I2C driver for fast
4512 mode (400kHZ). This environment variable is used in
4513 initialization code. So, for changes to be effective
4514 it must be saved and board must be reset.
4516 initrd_high - restrict positioning of initrd images:
4517 If this variable is not set, initrd images will be
4518 copied to the highest possible address in RAM; this
4519 is usually what you want since it allows for
4520 maximum initrd size. If for some reason you want to
4521 make sure that the initrd image is loaded below the
4522 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4523 variable to a value of "no" or "off" or "0".
4524 Alternatively, you can set it to a maximum upper
4525 address to use (U-Boot will still check that it
4526 does not overwrite the U-Boot stack and data).
4528 For instance, when you have a system with 16 MB
4529 RAM, and want to reserve 4 MB from use by Linux,
4530 you can do this by adding "mem=12M" to the value of
4531 the "bootargs" variable. However, now you must make
4532 sure that the initrd image is placed in the first
4533 12 MB as well - this can be done with
4535 setenv initrd_high 00c00000
4537 If you set initrd_high to 0xFFFFFFFF, this is an
4538 indication to U-Boot that all addresses are legal
4539 for the Linux kernel, including addresses in flash
4540 memory. In this case U-Boot will NOT COPY the
4541 ramdisk at all. This may be useful to reduce the
4542 boot time on your system, but requires that this
4543 feature is supported by your Linux kernel.
4545 ipaddr - IP address; needed for tftpboot command
4547 loadaddr - Default load address for commands like "bootp",
4548 "rarpboot", "tftpboot", "loadb" or "diskboot"
4550 loads_echo - see CONFIG_LOADS_ECHO
4552 serverip - TFTP server IP address; needed for tftpboot command
4554 bootretry - see CONFIG_BOOT_RETRY_TIME
4556 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4558 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4560 ethprime - controls which interface is used first.
4562 ethact - controls which interface is currently active.
4563 For example you can do the following
4565 => setenv ethact FEC
4566 => ping 192.168.0.1 # traffic sent on FEC
4567 => setenv ethact SCC
4568 => ping 10.0.0.1 # traffic sent on SCC
4570 ethrotate - When set to "no" U-Boot does not go through all
4571 available network interfaces.
4572 It just stays at the currently selected interface.
4574 netretry - When set to "no" each network operation will
4575 either succeed or fail without retrying.
4576 When set to "once" the network operation will
4577 fail when all the available network interfaces
4578 are tried once without success.
4579 Useful on scripts which control the retry operation
4582 npe_ucode - set load address for the NPE microcode
4584 tftpsrcport - If this is set, the value is used for TFTP's
4587 tftpdstport - If this is set, the value is used for TFTP's UDP
4588 destination port instead of the Well Know Port 69.
4590 tftpblocksize - Block size to use for TFTP transfers; if not set,
4591 we use the TFTP server's default block size
4593 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4594 seconds, minimum value is 1000 = 1 second). Defines
4595 when a packet is considered to be lost so it has to
4596 be retransmitted. The default is 5000 = 5 seconds.
4597 Lowering this value may make downloads succeed
4598 faster in networks with high packet loss rates or
4599 with unreliable TFTP servers.
4601 vlan - When set to a value < 4095 the traffic over
4602 Ethernet is encapsulated/received over 802.1q
4605 The following image location variables contain the location of images
4606 used in booting. The "Image" column gives the role of the image and is
4607 not an environment variable name. The other columns are environment
4608 variable names. "File Name" gives the name of the file on a TFTP
4609 server, "RAM Address" gives the location in RAM the image will be
4610 loaded to, and "Flash Location" gives the image's address in NOR
4611 flash or offset in NAND flash.
4613 *Note* - these variables don't have to be defined for all boards, some
4614 boards currenlty use other variables for these purposes, and some
4615 boards use these variables for other purposes.
4617 Image File Name RAM Address Flash Location
4618 ----- --------- ----------- --------------
4619 u-boot u-boot u-boot_addr_r u-boot_addr
4620 Linux kernel bootfile kernel_addr_r kernel_addr
4621 device tree blob fdtfile fdt_addr_r fdt_addr
4622 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4624 The following environment variables may be used and automatically
4625 updated by the network boot commands ("bootp" and "rarpboot"),
4626 depending the information provided by your boot server:
4628 bootfile - see above
4629 dnsip - IP address of your Domain Name Server
4630 dnsip2 - IP address of your secondary Domain Name Server
4631 gatewayip - IP address of the Gateway (Router) to use
4632 hostname - Target hostname
4634 netmask - Subnet Mask
4635 rootpath - Pathname of the root filesystem on the NFS server
4636 serverip - see above
4639 There are two special Environment Variables:
4641 serial# - contains hardware identification information such
4642 as type string and/or serial number
4643 ethaddr - Ethernet address
4645 These variables can be set only once (usually during manufacturing of
4646 the board). U-Boot refuses to delete or overwrite these variables
4647 once they have been set once.
4650 Further special Environment Variables:
4652 ver - Contains the U-Boot version string as printed
4653 with the "version" command. This variable is
4654 readonly (see CONFIG_VERSION_VARIABLE).
4657 Please note that changes to some configuration parameters may take
4658 only effect after the next boot (yes, that's just like Windoze :-).
4661 Callback functions for environment variables:
4662 ---------------------------------------------
4664 For some environment variables, the behavior of u-boot needs to change
4665 when their values are changed. This functionailty allows functions to
4666 be associated with arbitrary variables. On creation, overwrite, or
4667 deletion, the callback will provide the opportunity for some side
4668 effect to happen or for the change to be rejected.
4670 The callbacks are named and associated with a function using the
4671 U_BOOT_ENV_CALLBACK macro in your board or driver code.
4673 These callbacks are associated with variables in one of two ways. The
4674 static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
4675 in the board configuration to a string that defines a list of
4676 associations. The list must be in the following format:
4678 entry = variable_name[:callback_name]
4681 If the callback name is not specified, then the callback is deleted.
4682 Spaces are also allowed anywhere in the list.
4684 Callbacks can also be associated by defining the ".callbacks" variable
4685 with the same list format above. Any association in ".callbacks" will
4686 override any association in the static list. You can define
4687 CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
4688 ".callbacks" envirnoment variable in the default or embedded environment.
4691 Command Line Parsing:
4692 =====================
4694 There are two different command line parsers available with U-Boot:
4695 the old "simple" one, and the much more powerful "hush" shell:
4697 Old, simple command line parser:
4698 --------------------------------
4700 - supports environment variables (through setenv / saveenv commands)
4701 - several commands on one line, separated by ';'
4702 - variable substitution using "... ${name} ..." syntax
4703 - special characters ('$', ';') can be escaped by prefixing with '\',
4705 setenv bootcmd bootm \${address}
4706 - You can also escape text by enclosing in single apostrophes, for example:
4707 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4712 - similar to Bourne shell, with control structures like
4713 if...then...else...fi, for...do...done; while...do...done,
4714 until...do...done, ...
4715 - supports environment ("global") variables (through setenv / saveenv
4716 commands) and local shell variables (through standard shell syntax
4717 "name=value"); only environment variables can be used with "run"
4723 (1) If a command line (or an environment variable executed by a "run"
4724 command) contains several commands separated by semicolon, and
4725 one of these commands fails, then the remaining commands will be
4728 (2) If you execute several variables with one call to run (i. e.
4729 calling run with a list of variables as arguments), any failing
4730 command will cause "run" to terminate, i. e. the remaining
4731 variables are not executed.
4733 Note for Redundant Ethernet Interfaces:
4734 =======================================
4736 Some boards come with redundant Ethernet interfaces; U-Boot supports
4737 such configurations and is capable of automatic selection of a
4738 "working" interface when needed. MAC assignment works as follows:
4740 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4741 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4742 "eth1addr" (=>eth1), "eth2addr", ...
4744 If the network interface stores some valid MAC address (for instance
4745 in SROM), this is used as default address if there is NO correspon-
4746 ding setting in the environment; if the corresponding environment
4747 variable is set, this overrides the settings in the card; that means:
4749 o If the SROM has a valid MAC address, and there is no address in the
4750 environment, the SROM's address is used.
4752 o If there is no valid address in the SROM, and a definition in the
4753 environment exists, then the value from the environment variable is
4756 o If both the SROM and the environment contain a MAC address, and
4757 both addresses are the same, this MAC address is used.
4759 o If both the SROM and the environment contain a MAC address, and the
4760 addresses differ, the value from the environment is used and a
4763 o If neither SROM nor the environment contain a MAC address, an error
4766 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4767 will be programmed into hardware as part of the initialization process. This
4768 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4769 The naming convention is as follows:
4770 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4775 U-Boot is capable of booting (and performing other auxiliary operations on)
4776 images in two formats:
4778 New uImage format (FIT)
4779 -----------------------
4781 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4782 to Flattened Device Tree). It allows the use of images with multiple
4783 components (several kernels, ramdisks, etc.), with contents protected by
4784 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4790 Old image format is based on binary files which can be basically anything,
4791 preceded by a special header; see the definitions in include/image.h for
4792 details; basically, the header defines the following image properties:
4794 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4795 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4796 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4797 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4799 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4800 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4801 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4802 * Compression Type (uncompressed, gzip, bzip2)
4808 The header is marked by a special Magic Number, and both the header
4809 and the data portions of the image are secured against corruption by
4816 Although U-Boot should support any OS or standalone application
4817 easily, the main focus has always been on Linux during the design of
4820 U-Boot includes many features that so far have been part of some
4821 special "boot loader" code within the Linux kernel. Also, any
4822 "initrd" images to be used are no longer part of one big Linux image;
4823 instead, kernel and "initrd" are separate images. This implementation
4824 serves several purposes:
4826 - the same features can be used for other OS or standalone
4827 applications (for instance: using compressed images to reduce the
4828 Flash memory footprint)
4830 - it becomes much easier to port new Linux kernel versions because
4831 lots of low-level, hardware dependent stuff are done by U-Boot
4833 - the same Linux kernel image can now be used with different "initrd"
4834 images; of course this also means that different kernel images can
4835 be run with the same "initrd". This makes testing easier (you don't
4836 have to build a new "zImage.initrd" Linux image when you just
4837 change a file in your "initrd"). Also, a field-upgrade of the
4838 software is easier now.
4844 Porting Linux to U-Boot based systems:
4845 ---------------------------------------
4847 U-Boot cannot save you from doing all the necessary modifications to
4848 configure the Linux device drivers for use with your target hardware
4849 (no, we don't intend to provide a full virtual machine interface to
4852 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4854 Just make sure your machine specific header file (for instance
4855 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4856 Information structure as we define in include/asm-<arch>/u-boot.h,
4857 and make sure that your definition of IMAP_ADDR uses the same value
4858 as your U-Boot configuration in CONFIG_SYS_IMMR.
4861 Configuring the Linux kernel:
4862 -----------------------------
4864 No specific requirements for U-Boot. Make sure you have some root
4865 device (initial ramdisk, NFS) for your target system.
4868 Building a Linux Image:
4869 -----------------------
4871 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4872 not used. If you use recent kernel source, a new build target
4873 "uImage" will exist which automatically builds an image usable by
4874 U-Boot. Most older kernels also have support for a "pImage" target,
4875 which was introduced for our predecessor project PPCBoot and uses a
4876 100% compatible format.
4885 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4886 encapsulate a compressed Linux kernel image with header information,
4887 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4889 * build a standard "vmlinux" kernel image (in ELF binary format):
4891 * convert the kernel into a raw binary image:
4893 ${CROSS_COMPILE}-objcopy -O binary \
4894 -R .note -R .comment \
4895 -S vmlinux linux.bin
4897 * compress the binary image:
4901 * package compressed binary image for U-Boot:
4903 mkimage -A ppc -O linux -T kernel -C gzip \
4904 -a 0 -e 0 -n "Linux Kernel Image" \
4905 -d linux.bin.gz uImage
4908 The "mkimage" tool can also be used to create ramdisk images for use
4909 with U-Boot, either separated from the Linux kernel image, or
4910 combined into one file. "mkimage" encapsulates the images with a 64
4911 byte header containing information about target architecture,
4912 operating system, image type, compression method, entry points, time
4913 stamp, CRC32 checksums, etc.
4915 "mkimage" can be called in two ways: to verify existing images and
4916 print the header information, or to build new images.
4918 In the first form (with "-l" option) mkimage lists the information
4919 contained in the header of an existing U-Boot image; this includes
4920 checksum verification:
4922 tools/mkimage -l image
4923 -l ==> list image header information
4925 The second form (with "-d" option) is used to build a U-Boot image
4926 from a "data file" which is used as image payload:
4928 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4929 -n name -d data_file image
4930 -A ==> set architecture to 'arch'
4931 -O ==> set operating system to 'os'
4932 -T ==> set image type to 'type'
4933 -C ==> set compression type 'comp'
4934 -a ==> set load address to 'addr' (hex)
4935 -e ==> set entry point to 'ep' (hex)
4936 -n ==> set image name to 'name'
4937 -d ==> use image data from 'datafile'
4939 Right now, all Linux kernels for PowerPC systems use the same load
4940 address (0x00000000), but the entry point address depends on the
4943 - 2.2.x kernels have the entry point at 0x0000000C,
4944 - 2.3.x and later kernels have the entry point at 0x00000000.
4946 So a typical call to build a U-Boot image would read:
4948 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4949 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4950 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4951 > examples/uImage.TQM850L
4952 Image Name: 2.4.4 kernel for TQM850L
4953 Created: Wed Jul 19 02:34:59 2000
4954 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4955 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4956 Load Address: 0x00000000
4957 Entry Point: 0x00000000
4959 To verify the contents of the image (or check for corruption):
4961 -> tools/mkimage -l examples/uImage.TQM850L
4962 Image Name: 2.4.4 kernel for TQM850L
4963 Created: Wed Jul 19 02:34:59 2000
4964 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4965 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4966 Load Address: 0x00000000
4967 Entry Point: 0x00000000
4969 NOTE: for embedded systems where boot time is critical you can trade
4970 speed for memory and install an UNCOMPRESSED image instead: this
4971 needs more space in Flash, but boots much faster since it does not
4972 need to be uncompressed:
4974 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
4975 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4976 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4977 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
4978 > examples/uImage.TQM850L-uncompressed
4979 Image Name: 2.4.4 kernel for TQM850L
4980 Created: Wed Jul 19 02:34:59 2000
4981 Image Type: PowerPC Linux Kernel Image (uncompressed)
4982 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4983 Load Address: 0x00000000
4984 Entry Point: 0x00000000
4987 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4988 when your kernel is intended to use an initial ramdisk:
4990 -> tools/mkimage -n 'Simple Ramdisk Image' \
4991 > -A ppc -O linux -T ramdisk -C gzip \
4992 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4993 Image Name: Simple Ramdisk Image
4994 Created: Wed Jan 12 14:01:50 2000
4995 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4996 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4997 Load Address: 0x00000000
4998 Entry Point: 0x00000000
5001 Installing a Linux Image:
5002 -------------------------
5004 To downloading a U-Boot image over the serial (console) interface,
5005 you must convert the image to S-Record format:
5007 objcopy -I binary -O srec examples/image examples/image.srec
5009 The 'objcopy' does not understand the information in the U-Boot
5010 image header, so the resulting S-Record file will be relative to
5011 address 0x00000000. To load it to a given address, you need to
5012 specify the target address as 'offset' parameter with the 'loads'
5015 Example: install the image to address 0x40100000 (which on the
5016 TQM8xxL is in the first Flash bank):
5018 => erase 40100000 401FFFFF
5024 ## Ready for S-Record download ...
5025 ~>examples/image.srec
5026 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
5028 15989 15990 15991 15992
5029 [file transfer complete]
5031 ## Start Addr = 0x00000000
5034 You can check the success of the download using the 'iminfo' command;
5035 this includes a checksum verification so you can be sure no data
5036 corruption happened:
5040 ## Checking Image at 40100000 ...
5041 Image Name: 2.2.13 for initrd on TQM850L
5042 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5043 Data Size: 335725 Bytes = 327 kB = 0 MB
5044 Load Address: 00000000
5045 Entry Point: 0000000c
5046 Verifying Checksum ... OK
5052 The "bootm" command is used to boot an application that is stored in
5053 memory (RAM or Flash). In case of a Linux kernel image, the contents
5054 of the "bootargs" environment variable is passed to the kernel as
5055 parameters. You can check and modify this variable using the
5056 "printenv" and "setenv" commands:
5059 => printenv bootargs
5060 bootargs=root=/dev/ram
5062 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5064 => printenv bootargs
5065 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5068 ## Booting Linux kernel at 40020000 ...
5069 Image Name: 2.2.13 for NFS on TQM850L
5070 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5071 Data Size: 381681 Bytes = 372 kB = 0 MB
5072 Load Address: 00000000
5073 Entry Point: 0000000c
5074 Verifying Checksum ... OK
5075 Uncompressing Kernel Image ... OK
5076 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
5077 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
5078 time_init: decrementer frequency = 187500000/60
5079 Calibrating delay loop... 49.77 BogoMIPS
5080 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
5083 If you want to boot a Linux kernel with initial RAM disk, you pass
5084 the memory addresses of both the kernel and the initrd image (PPBCOOT
5085 format!) to the "bootm" command:
5087 => imi 40100000 40200000
5089 ## Checking Image at 40100000 ...
5090 Image Name: 2.2.13 for initrd on TQM850L
5091 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5092 Data Size: 335725 Bytes = 327 kB = 0 MB
5093 Load Address: 00000000
5094 Entry Point: 0000000c
5095 Verifying Checksum ... OK
5097 ## Checking Image at 40200000 ...
5098 Image Name: Simple Ramdisk Image
5099 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5100 Data Size: 566530 Bytes = 553 kB = 0 MB
5101 Load Address: 00000000
5102 Entry Point: 00000000
5103 Verifying Checksum ... OK
5105 => bootm 40100000 40200000
5106 ## Booting Linux kernel at 40100000 ...
5107 Image Name: 2.2.13 for initrd on TQM850L
5108 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5109 Data Size: 335725 Bytes = 327 kB = 0 MB
5110 Load Address: 00000000
5111 Entry Point: 0000000c
5112 Verifying Checksum ... OK
5113 Uncompressing Kernel Image ... OK
5114 ## Loading RAMDisk Image at 40200000 ...
5115 Image Name: Simple Ramdisk Image
5116 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
5117 Data Size: 566530 Bytes = 553 kB = 0 MB
5118 Load Address: 00000000
5119 Entry Point: 00000000
5120 Verifying Checksum ... OK
5121 Loading Ramdisk ... OK
5122 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
5123 Boot arguments: root=/dev/ram
5124 time_init: decrementer frequency = 187500000/60
5125 Calibrating delay loop... 49.77 BogoMIPS
5127 RAMDISK: Compressed image found at block 0
5128 VFS: Mounted root (ext2 filesystem).
5132 Boot Linux and pass a flat device tree:
5135 First, U-Boot must be compiled with the appropriate defines. See the section
5136 titled "Linux Kernel Interface" above for a more in depth explanation. The
5137 following is an example of how to start a kernel and pass an updated
5143 oft=oftrees/mpc8540ads.dtb
5144 => tftp $oftaddr $oft
5145 Speed: 1000, full duplex
5147 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
5148 Filename 'oftrees/mpc8540ads.dtb'.
5149 Load address: 0x300000
5152 Bytes transferred = 4106 (100a hex)
5153 => tftp $loadaddr $bootfile
5154 Speed: 1000, full duplex
5156 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
5158 Load address: 0x200000
5159 Loading:############
5161 Bytes transferred = 1029407 (fb51f hex)
5166 => bootm $loadaddr - $oftaddr
5167 ## Booting image at 00200000 ...
5168 Image Name: Linux-2.6.17-dirty
5169 Image Type: PowerPC Linux Kernel Image (gzip compressed)
5170 Data Size: 1029343 Bytes = 1005.2 kB
5171 Load Address: 00000000
5172 Entry Point: 00000000
5173 Verifying Checksum ... OK
5174 Uncompressing Kernel Image ... OK
5175 Booting using flat device tree at 0x300000
5176 Using MPC85xx ADS machine description
5177 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
5181 More About U-Boot Image Types:
5182 ------------------------------
5184 U-Boot supports the following image types:
5186 "Standalone Programs" are directly runnable in the environment
5187 provided by U-Boot; it is expected that (if they behave
5188 well) you can continue to work in U-Boot after return from
5189 the Standalone Program.
5190 "OS Kernel Images" are usually images of some Embedded OS which
5191 will take over control completely. Usually these programs
5192 will install their own set of exception handlers, device
5193 drivers, set up the MMU, etc. - this means, that you cannot
5194 expect to re-enter U-Boot except by resetting the CPU.
5195 "RAMDisk Images" are more or less just data blocks, and their
5196 parameters (address, size) are passed to an OS kernel that is
5198 "Multi-File Images" contain several images, typically an OS
5199 (Linux) kernel image and one or more data images like
5200 RAMDisks. This construct is useful for instance when you want
5201 to boot over the network using BOOTP etc., where the boot
5202 server provides just a single image file, but you want to get
5203 for instance an OS kernel and a RAMDisk image.
5205 "Multi-File Images" start with a list of image sizes, each
5206 image size (in bytes) specified by an "uint32_t" in network
5207 byte order. This list is terminated by an "(uint32_t)0".
5208 Immediately after the terminating 0 follow the images, one by
5209 one, all aligned on "uint32_t" boundaries (size rounded up to
5210 a multiple of 4 bytes).
5212 "Firmware Images" are binary images containing firmware (like
5213 U-Boot or FPGA images) which usually will be programmed to
5216 "Script files" are command sequences that will be executed by
5217 U-Boot's command interpreter; this feature is especially
5218 useful when you configure U-Boot to use a real shell (hush)
5219 as command interpreter.
5221 Booting the Linux zImage:
5222 -------------------------
5224 On some platforms, it's possible to boot Linux zImage. This is done
5225 using the "bootz" command. The syntax of "bootz" command is the same
5226 as the syntax of "bootm" command.
5228 Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
5229 kernel with raw initrd images. The syntax is slightly different, the
5230 address of the initrd must be augmented by it's size, in the following
5231 format: "<initrd addres>:<initrd size>".
5237 One of the features of U-Boot is that you can dynamically load and
5238 run "standalone" applications, which can use some resources of
5239 U-Boot like console I/O functions or interrupt services.
5241 Two simple examples are included with the sources:
5246 'examples/hello_world.c' contains a small "Hello World" Demo
5247 application; it is automatically compiled when you build U-Boot.
5248 It's configured to run at address 0x00040004, so you can play with it
5252 ## Ready for S-Record download ...
5253 ~>examples/hello_world.srec
5254 1 2 3 4 5 6 7 8 9 10 11 ...
5255 [file transfer complete]
5257 ## Start Addr = 0x00040004
5259 => go 40004 Hello World! This is a test.
5260 ## Starting application at 0x00040004 ...
5271 Hit any key to exit ...
5273 ## Application terminated, rc = 0x0
5275 Another example, which demonstrates how to register a CPM interrupt
5276 handler with the U-Boot code, can be found in 'examples/timer.c'.
5277 Here, a CPM timer is set up to generate an interrupt every second.
5278 The interrupt service routine is trivial, just printing a '.'
5279 character, but this is just a demo program. The application can be
5280 controlled by the following keys:
5282 ? - print current values og the CPM Timer registers
5283 b - enable interrupts and start timer
5284 e - stop timer and disable interrupts
5285 q - quit application
5288 ## Ready for S-Record download ...
5289 ~>examples/timer.srec
5290 1 2 3 4 5 6 7 8 9 10 11 ...
5291 [file transfer complete]
5293 ## Start Addr = 0x00040004
5296 ## Starting application at 0x00040004 ...
5299 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
5302 [q, b, e, ?] Set interval 1000000 us
5305 [q, b, e, ?] ........
5306 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
5309 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
5312 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
5315 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
5317 [q, b, e, ?] ...Stopping timer
5319 [q, b, e, ?] ## Application terminated, rc = 0x0
5325 Over time, many people have reported problems when trying to use the
5326 "minicom" terminal emulation program for serial download. I (wd)
5327 consider minicom to be broken, and recommend not to use it. Under
5328 Unix, I recommend to use C-Kermit for general purpose use (and
5329 especially for kermit binary protocol download ("loadb" command), and
5330 use "cu" for S-Record download ("loads" command). See
5331 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
5332 for help with kermit.
5335 Nevertheless, if you absolutely want to use it try adding this
5336 configuration to your "File transfer protocols" section:
5338 Name Program Name U/D FullScr IO-Red. Multi
5339 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
5340 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
5346 Starting at version 0.9.2, U-Boot supports NetBSD both as host
5347 (build U-Boot) and target system (boots NetBSD/mpc8xx).
5349 Building requires a cross environment; it is known to work on
5350 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
5351 need gmake since the Makefiles are not compatible with BSD make).
5352 Note that the cross-powerpc package does not install include files;
5353 attempting to build U-Boot will fail because <machine/ansi.h> is
5354 missing. This file has to be installed and patched manually:
5356 # cd /usr/pkg/cross/powerpc-netbsd/include
5358 # ln -s powerpc machine
5359 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
5360 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
5362 Native builds *don't* work due to incompatibilities between native
5363 and U-Boot include files.
5365 Booting assumes that (the first part of) the image booted is a
5366 stage-2 loader which in turn loads and then invokes the kernel
5367 proper. Loader sources will eventually appear in the NetBSD source
5368 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
5369 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
5372 Implementation Internals:
5373 =========================
5375 The following is not intended to be a complete description of every
5376 implementation detail. However, it should help to understand the
5377 inner workings of U-Boot and make it easier to port it to custom
5381 Initial Stack, Global Data:
5382 ---------------------------
5384 The implementation of U-Boot is complicated by the fact that U-Boot
5385 starts running out of ROM (flash memory), usually without access to
5386 system RAM (because the memory controller is not initialized yet).
5387 This means that we don't have writable Data or BSS segments, and BSS
5388 is not initialized as zero. To be able to get a C environment working
5389 at all, we have to allocate at least a minimal stack. Implementation
5390 options for this are defined and restricted by the CPU used: Some CPU
5391 models provide on-chip memory (like the IMMR area on MPC8xx and
5392 MPC826x processors), on others (parts of) the data cache can be
5393 locked as (mis-) used as memory, etc.
5395 Chris Hallinan posted a good summary of these issues to the
5396 U-Boot mailing list:
5398 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
5399 From: "Chris Hallinan" <clh@net1plus.com>
5400 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
5403 Correct me if I'm wrong, folks, but the way I understand it
5404 is this: Using DCACHE as initial RAM for Stack, etc, does not
5405 require any physical RAM backing up the cache. The cleverness
5406 is that the cache is being used as a temporary supply of
5407 necessary storage before the SDRAM controller is setup. It's
5408 beyond the scope of this list to explain the details, but you
5409 can see how this works by studying the cache architecture and
5410 operation in the architecture and processor-specific manuals.
5412 OCM is On Chip Memory, which I believe the 405GP has 4K. It
5413 is another option for the system designer to use as an
5414 initial stack/RAM area prior to SDRAM being available. Either
5415 option should work for you. Using CS 4 should be fine if your
5416 board designers haven't used it for something that would
5417 cause you grief during the initial boot! It is frequently not
5420 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
5421 with your processor/board/system design. The default value
5422 you will find in any recent u-boot distribution in
5423 walnut.h should work for you. I'd set it to a value larger
5424 than your SDRAM module. If you have a 64MB SDRAM module, set
5425 it above 400_0000. Just make sure your board has no resources
5426 that are supposed to respond to that address! That code in
5427 start.S has been around a while and should work as is when
5428 you get the config right.
5433 It is essential to remember this, since it has some impact on the C
5434 code for the initialization procedures:
5436 * Initialized global data (data segment) is read-only. Do not attempt
5439 * Do not use any uninitialized global data (or implicitely initialized
5440 as zero data - BSS segment) at all - this is undefined, initiali-
5441 zation is performed later (when relocating to RAM).
5443 * Stack space is very limited. Avoid big data buffers or things like
5446 Having only the stack as writable memory limits means we cannot use
5447 normal global data to share information beween the code. But it
5448 turned out that the implementation of U-Boot can be greatly
5449 simplified by making a global data structure (gd_t) available to all
5450 functions. We could pass a pointer to this data as argument to _all_
5451 functions, but this would bloat the code. Instead we use a feature of
5452 the GCC compiler (Global Register Variables) to share the data: we
5453 place a pointer (gd) to the global data into a register which we
5454 reserve for this purpose.
5456 When choosing a register for such a purpose we are restricted by the
5457 relevant (E)ABI specifications for the current architecture, and by
5458 GCC's implementation.
5460 For PowerPC, the following registers have specific use:
5462 R2: reserved for system use
5463 R3-R4: parameter passing and return values
5464 R5-R10: parameter passing
5465 R13: small data area pointer
5469 (U-Boot also uses R12 as internal GOT pointer. r12
5470 is a volatile register so r12 needs to be reset when
5471 going back and forth between asm and C)
5473 ==> U-Boot will use R2 to hold a pointer to the global data
5475 Note: on PPC, we could use a static initializer (since the
5476 address of the global data structure is known at compile time),
5477 but it turned out that reserving a register results in somewhat
5478 smaller code - although the code savings are not that big (on
5479 average for all boards 752 bytes for the whole U-Boot image,
5480 624 text + 127 data).
5482 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5483 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5485 ==> U-Boot will use P3 to hold a pointer to the global data
5487 On ARM, the following registers are used:
5489 R0: function argument word/integer result
5490 R1-R3: function argument word
5492 R10: stack limit (used only if stack checking if enabled)
5493 R11: argument (frame) pointer
5494 R12: temporary workspace
5497 R15: program counter
5499 ==> U-Boot will use R8 to hold a pointer to the global data
5501 On Nios II, the ABI is documented here:
5502 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5504 ==> U-Boot will use gp to hold a pointer to the global data
5506 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5507 to access small data sections, so gp is free.
5509 On NDS32, the following registers are used:
5511 R0-R1: argument/return
5513 R15: temporary register for assembler
5514 R16: trampoline register
5515 R28: frame pointer (FP)
5516 R29: global pointer (GP)
5517 R30: link register (LP)
5518 R31: stack pointer (SP)
5519 PC: program counter (PC)
5521 ==> U-Boot will use R10 to hold a pointer to the global data
5523 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5524 or current versions of GCC may "optimize" the code too much.
5529 U-Boot runs in system state and uses physical addresses, i.e. the
5530 MMU is not used either for address mapping nor for memory protection.
5532 The available memory is mapped to fixed addresses using the memory
5533 controller. In this process, a contiguous block is formed for each
5534 memory type (Flash, SDRAM, SRAM), even when it consists of several
5535 physical memory banks.
5537 U-Boot is installed in the first 128 kB of the first Flash bank (on
5538 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5539 booting and sizing and initializing DRAM, the code relocates itself
5540 to the upper end of DRAM. Immediately below the U-Boot code some
5541 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5542 configuration setting]. Below that, a structure with global Board
5543 Info data is placed, followed by the stack (growing downward).
5545 Additionally, some exception handler code is copied to the low 8 kB
5546 of DRAM (0x00000000 ... 0x00001FFF).
5548 So a typical memory configuration with 16 MB of DRAM could look like
5551 0x0000 0000 Exception Vector code
5554 0x0000 2000 Free for Application Use
5560 0x00FB FF20 Monitor Stack (Growing downward)
5561 0x00FB FFAC Board Info Data and permanent copy of global data
5562 0x00FC 0000 Malloc Arena
5565 0x00FE 0000 RAM Copy of Monitor Code
5566 ... eventually: LCD or video framebuffer
5567 ... eventually: pRAM (Protected RAM - unchanged by reset)
5568 0x00FF FFFF [End of RAM]
5571 System Initialization:
5572 ----------------------
5574 In the reset configuration, U-Boot starts at the reset entry point
5575 (on most PowerPC systems at address 0x00000100). Because of the reset
5576 configuration for CS0# this is a mirror of the onboard Flash memory.
5577 To be able to re-map memory U-Boot then jumps to its link address.
5578 To be able to implement the initialization code in C, a (small!)
5579 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5580 which provide such a feature like MPC8xx or MPC8260), or in a locked
5581 part of the data cache. After that, U-Boot initializes the CPU core,
5582 the caches and the SIU.
5584 Next, all (potentially) available memory banks are mapped using a
5585 preliminary mapping. For example, we put them on 512 MB boundaries
5586 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5587 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5588 programmed for SDRAM access. Using the temporary configuration, a
5589 simple memory test is run that determines the size of the SDRAM
5592 When there is more than one SDRAM bank, and the banks are of
5593 different size, the largest is mapped first. For equal size, the first
5594 bank (CS2#) is mapped first. The first mapping is always for address
5595 0x00000000, with any additional banks following immediately to create
5596 contiguous memory starting from 0.
5598 Then, the monitor installs itself at the upper end of the SDRAM area
5599 and allocates memory for use by malloc() and for the global Board
5600 Info data; also, the exception vector code is copied to the low RAM
5601 pages, and the final stack is set up.
5603 Only after this relocation will you have a "normal" C environment;
5604 until that you are restricted in several ways, mostly because you are
5605 running from ROM, and because the code will have to be relocated to a
5609 U-Boot Porting Guide:
5610 ----------------------
5612 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5616 int main(int argc, char *argv[])
5618 sighandler_t no_more_time;
5620 signal(SIGALRM, no_more_time);
5621 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5623 if (available_money > available_manpower) {
5624 Pay consultant to port U-Boot;
5628 Download latest U-Boot source;
5630 Subscribe to u-boot mailing list;
5633 email("Hi, I am new to U-Boot, how do I get started?");
5636 Read the README file in the top level directory;
5637 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5638 Read applicable doc/*.README;
5639 Read the source, Luke;
5640 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5643 if (available_money > toLocalCurrency ($2500))
5646 Add a lot of aggravation and time;
5648 if (a similar board exists) { /* hopefully... */
5649 cp -a board/<similar> board/<myboard>
5650 cp include/configs/<similar>.h include/configs/<myboard>.h
5652 Create your own board support subdirectory;
5653 Create your own board include/configs/<myboard>.h file;
5655 Edit new board/<myboard> files
5656 Edit new include/configs/<myboard>.h
5661 Add / modify source code;
5665 email("Hi, I am having problems...");
5667 Send patch file to the U-Boot email list;
5668 if (reasonable critiques)
5669 Incorporate improvements from email list code review;
5671 Defend code as written;
5677 void no_more_time (int sig)
5686 All contributions to U-Boot should conform to the Linux kernel
5687 coding style; see the file "Documentation/CodingStyle" and the script
5688 "scripts/Lindent" in your Linux kernel source directory.
5690 Source files originating from a different project (for example the
5691 MTD subsystem) are generally exempt from these guidelines and are not
5692 reformated to ease subsequent migration to newer versions of those
5695 Please note that U-Boot is implemented in C (and to some small parts in
5696 Assembler); no C++ is used, so please do not use C++ style comments (//)
5699 Please also stick to the following formatting rules:
5700 - remove any trailing white space
5701 - use TAB characters for indentation and vertical alignment, not spaces
5702 - make sure NOT to use DOS '\r\n' line feeds
5703 - do not add more than 2 consecutive empty lines to source files
5704 - do not add trailing empty lines to source files
5706 Submissions which do not conform to the standards may be returned
5707 with a request to reformat the changes.
5713 Since the number of patches for U-Boot is growing, we need to
5714 establish some rules. Submissions which do not conform to these rules
5715 may be rejected, even when they contain important and valuable stuff.
5717 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5719 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5720 see http://lists.denx.de/mailman/listinfo/u-boot
5722 When you send a patch, please include the following information with
5725 * For bug fixes: a description of the bug and how your patch fixes
5726 this bug. Please try to include a way of demonstrating that the
5727 patch actually fixes something.
5729 * For new features: a description of the feature and your
5732 * A CHANGELOG entry as plaintext (separate from the patch)
5734 * For major contributions, your entry to the CREDITS file
5736 * When you add support for a new board, don't forget to add this
5737 board to the MAINTAINERS file, too.
5739 * If your patch adds new configuration options, don't forget to
5740 document these in the README file.
5742 * The patch itself. If you are using git (which is *strongly*
5743 recommended) you can easily generate the patch using the
5744 "git format-patch". If you then use "git send-email" to send it to
5745 the U-Boot mailing list, you will avoid most of the common problems
5746 with some other mail clients.
5748 If you cannot use git, use "diff -purN OLD NEW". If your version of
5749 diff does not support these options, then get the latest version of
5752 The current directory when running this command shall be the parent
5753 directory of the U-Boot source tree (i. e. please make sure that
5754 your patch includes sufficient directory information for the
5757 We prefer patches as plain text. MIME attachments are discouraged,
5758 and compressed attachments must not be used.
5760 * If one logical set of modifications affects or creates several
5761 files, all these changes shall be submitted in a SINGLE patch file.
5763 * Changesets that contain different, unrelated modifications shall be
5764 submitted as SEPARATE patches, one patch per changeset.
5769 * Before sending the patch, run the MAKEALL script on your patched
5770 source tree and make sure that no errors or warnings are reported
5771 for any of the boards.
5773 * Keep your modifications to the necessary minimum: A patch
5774 containing several unrelated changes or arbitrary reformats will be
5775 returned with a request to re-formatting / split it.
5777 * If you modify existing code, make sure that your new code does not
5778 add to the memory footprint of the code ;-) Small is beautiful!
5779 When adding new features, these should compile conditionally only
5780 (using #ifdef), and the resulting code with the new feature
5781 disabled must not need more memory than the old code without your
5784 * Remember that there is a size limit of 100 kB per message on the
5785 u-boot mailing list. Bigger patches will be moderated. If they are
5786 reasonable and not too big, they will be acknowledged. But patches
5787 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob