2 # (C) Copyright 2000 - 2005
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.
60 In case you have questions about, problems with or contributions for
61 U-Boot you should send a message to the U-Boot mailing list at
62 <u-boot-users@lists.sourceforge.net>. There is also an archive of
63 previous traffic on the mailing list - please search the archive
64 before asking FAQ's. Please see
65 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
71 - start from 8xxrom sources
72 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
74 - make it easier to add custom boards
75 - make it possible to add other [PowerPC] CPUs
76 - extend functions, especially:
77 * Provide extended interface to Linux boot loader
80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
81 - create ARMBoot project (http://sourceforge.net/projects/armboot)
82 - add other CPU families (starting with ARM)
83 - create U-Boot project (http://sourceforge.net/projects/u-boot)
89 The "official" name of this project is "Das U-Boot". The spelling
90 "U-Boot" shall be used in all written text (documentation, comments
91 in source files etc.). Example:
93 This is the README file for the U-Boot project.
95 File names etc. shall be based on the string "u-boot". Examples:
97 include/asm-ppc/u-boot.h
99 #include <asm/u-boot.h>
101 Variable names, preprocessor constants etc. shall be either based on
102 the string "u_boot" or on "U_BOOT". Example:
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
111 U-Boot uses a 3 level version number containing a version, a
112 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
113 sub-version "34", and patchlevel "4".
115 The patchlevel is used to indicate certain stages of development
116 between released versions, i. e. officially released versions of
117 U-Boot will always have a patchlevel of "0".
123 - board Board dependent files
124 - common Misc architecture independent functions
125 - cpu CPU specific files
126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
127 - arm720t Files specific to ARM 720 CPUs
128 - arm920t Files specific to ARM 920 CPUs
129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
130 - imx Files specific to Freescale MC9328 i.MX CPUs
131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
132 - arm925t Files specific to ARM 925 CPUs
133 - arm926ejs Files specific to ARM 926 CPUs
134 - arm1136 Files specific to ARM 1136 CPUs
135 - i386 Files specific to i386 CPUs
136 - ixp Files specific to Intel XScale IXP CPUs
137 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
138 - mips Files specific to MIPS CPUs
139 - mpc5xx Files specific to Freescale MPC5xx CPUs
140 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
141 - mpc8xx Files specific to Freescale MPC8xx CPUs
142 - mpc8220 Files specific to Freescale MPC8220 CPUs
143 - mpc824x Files specific to Freescale MPC824x CPUs
144 - mpc8260 Files specific to Freescale MPC8260 CPUs
145 - mpc85xx Files specific to Freescale MPC85xx CPUs
146 - nios Files specific to Altera NIOS CPUs
147 - nios2 Files specific to Altera Nios-II CPUs
148 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs
149 - pxa Files specific to Intel XScale PXA CPUs
150 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
151 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
152 - disk Code for disk drive partition handling
153 - doc Documentation (don't expect too much)
154 - drivers Commonly used device drivers
155 - dtt Digital Thermometer and Thermostat drivers
156 - examples Example code for standalone applications, etc.
157 - include Header Files
158 - lib_arm Files generic to ARM architecture
159 - lib_generic Files generic to all architectures
160 - lib_i386 Files generic to i386 architecture
161 - lib_m68k Files generic to m68k architecture
162 - lib_mips Files generic to MIPS architecture
163 - lib_nios Files generic to NIOS architecture
164 - lib_ppc Files generic to PowerPC architecture
165 - net Networking code
166 - post Power On Self Test
167 - rtc Real Time Clock drivers
168 - tools Tools to build S-Record or U-Boot images, etc.
170 Software Configuration:
171 =======================
173 Configuration is usually done using C preprocessor defines; the
174 rationale behind that is to avoid dead code whenever possible.
176 There are two classes of configuration variables:
178 * Configuration _OPTIONS_:
179 These are selectable by the user and have names beginning with
182 * Configuration _SETTINGS_:
183 These depend on the hardware etc. and should not be meddled with if
184 you don't know what you're doing; they have names beginning with
187 Later we will add a configuration tool - probably similar to or even
188 identical to what's used for the Linux kernel. Right now, we have to
189 do the configuration by hand, which means creating some symbolic
190 links and editing some configuration files. We use the TQM8xxL boards
194 Selection of Processor Architecture and Board Type:
195 ---------------------------------------------------
197 For all supported boards there are ready-to-use default
198 configurations available; just type "make <board_name>_config".
200 Example: For a TQM823L module type:
205 For the Cogent platform, you need to specify the cpu type as well;
206 e.g. "make cogent_mpc8xx_config". And also configure the cogent
207 directory according to the instructions in cogent/README.
210 Configuration Options:
211 ----------------------
213 Configuration depends on the combination of board and CPU type; all
214 such information is kept in a configuration file
215 "include/configs/<board_name>.h".
217 Example: For a TQM823L module, all configuration settings are in
218 "include/configs/TQM823L.h".
221 Many of the options are named exactly as the corresponding Linux
222 kernel configuration options. The intention is to make it easier to
223 build a config tool - later.
226 The following options need to be configured:
228 - CPU Type: Define exactly one of
232 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
235 or CONFIG_MPC824X, CONFIG_MPC8260
250 MicroBlaze based CPUs:
251 ----------------------
255 ----------------------
259 - Board Type: Define exactly one of
261 PowerPC based boards:
262 ---------------------
264 CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCIPPC2
265 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC6
266 CONFIG_AMX860 CONFIG_GTH CONFIG_pcu_e
267 CONFIG_AP1000 CONFIG_gw8260 CONFIG_PIP405
268 CONFIG_AR405 CONFIG_hermes CONFIG_PM826
269 CONFIG_BAB7xx CONFIG_hymod CONFIG_ppmc8260
270 CONFIG_c2mon CONFIG_IAD210 CONFIG_QS823
271 CONFIG_CANBT CONFIG_ICU862 CONFIG_QS850
272 CONFIG_CCM CONFIG_IP860 CONFIG_QS860T
273 CONFIG_CMI CONFIG_IPHASE4539 CONFIG_RBC823
274 CONFIG_cogent_mpc8260 CONFIG_IVML24 CONFIG_RPXClassic
275 CONFIG_cogent_mpc8xx CONFIG_IVML24_128 CONFIG_RPXlite
276 CONFIG_CPCI405 CONFIG_IVML24_256 CONFIG_RPXsuper
277 CONFIG_CPCI4052 CONFIG_IVMS8 CONFIG_rsdproto
278 CONFIG_CPCIISER4 CONFIG_IVMS8_128 CONFIG_sacsng
279 CONFIG_CPU86 CONFIG_IVMS8_256 CONFIG_Sandpoint8240
280 CONFIG_CRAYL1 CONFIG_JSE CONFIG_Sandpoint8245
281 CONFIG_CSB272 CONFIG_LANTEC CONFIG_sbc8260
282 CONFIG_CU824 CONFIG_lwmon CONFIG_sbc8560
283 CONFIG_DASA_SIM CONFIG_MBX CONFIG_SM850
284 CONFIG_DB64360 CONFIG_MBX860T CONFIG_SPD823TS
285 CONFIG_DB64460 CONFIG_MHPC CONFIG_STXGP3
286 CONFIG_DU405 CONFIG_MIP405 CONFIG_SXNI855T
287 CONFIG_DUET_ADS CONFIG_MOUSSE CONFIG_TQM823L
288 CONFIG_EBONY CONFIG_MPC8260ADS CONFIG_TQM8260
289 CONFIG_ELPPC CONFIG_MPC8540ADS CONFIG_TQM850L
290 CONFIG_ELPT860 CONFIG_MPC8540EVAL CONFIG_TQM855L
291 CONFIG_ep8260 CONFIG_MPC8560ADS CONFIG_TQM860L
292 CONFIG_ERIC CONFIG_MUSENKI CONFIG_TTTech
293 CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_UTX8245
294 CONFIG_ETX094 CONFIG_NETPHONE CONFIG_V37
295 CONFIG_EVB64260 CONFIG_NETTA CONFIG_W7OLMC
296 CONFIG_FADS823 CONFIG_NETVIA CONFIG_W7OLMG
297 CONFIG_FADS850SAR CONFIG_NX823 CONFIG_WALNUT
298 CONFIG_FADS860T CONFIG_OCRTC CONFIG_ZPC1900
299 CONFIG_FLAGADM CONFIG_ORSG CONFIG_ZUMA
300 CONFIG_FPS850L CONFIG_OXC
301 CONFIG_FPS860L CONFIG_PCI405
306 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
307 CONFIG_CSB637, CONFIG_DNP1110, CONFIG_EP7312,
308 CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, CONFIG_IMPA7,
309 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, CONFIG_KB9202,
310 CONFIG_LART, CONFIG_LPD7A400, CONFIG_LUBBOCK,
311 CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, CONFIG_SHANNON,
312 CONFIG_P2_OMAP730, CONFIG_SMDK2400, CONFIG_SMDK2410,
313 CONFIG_TRAB, CONFIG_VCMA9
315 MicroBlaze based boards:
316 ------------------------
321 ------------------------
323 CONFIG_PCI5441 CONFIG_PK1C20
326 - CPU Module Type: (if CONFIG_COGENT is defined)
327 Define exactly one of
329 --- FIXME --- not tested yet:
330 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
331 CONFIG_CMA287_23, CONFIG_CMA287_50
333 - Motherboard Type: (if CONFIG_COGENT is defined)
334 Define exactly one of
335 CONFIG_CMA101, CONFIG_CMA102
337 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
338 Define one or more of
341 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
342 Define one or more of
343 CONFIG_LCD_HEARTBEAT - update a character position on
344 the lcd display every second with
347 - Board flavour: (if CONFIG_MPC8260ADS is defined)
350 CFG_8260ADS - original MPC8260ADS
351 CFG_8266ADS - MPC8266ADS
352 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
353 CFG_8272ADS - MPC8272ADS
355 - MPC824X Family Member (if CONFIG_MPC824X is defined)
356 Define exactly one of
357 CONFIG_MPC8240, CONFIG_MPC8245
359 - 8xx CPU Options: (if using an MPC8xx cpu)
360 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
361 get_gclk_freq() cannot work
362 e.g. if there is no 32KHz
363 reference PIT/RTC clock
364 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
367 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
370 CONFIG_8xx_CPUCLK_DEFAULT
371 See doc/README.MPC866
375 Define this to measure the actual CPU clock instead
376 of relying on the correctness of the configured
377 values. Mostly useful for board bringup to make sure
378 the PLL is locked at the intended frequency. Note
379 that this requires a (stable) reference clock (32 kHz
380 RTC clock or CFG_8XX_XIN)
382 - Linux Kernel Interface:
385 U-Boot stores all clock information in Hz
386 internally. For binary compatibility with older Linux
387 kernels (which expect the clocks passed in the
388 bd_info data to be in MHz) the environment variable
389 "clocks_in_mhz" can be defined so that U-Boot
390 converts clock data to MHZ before passing it to the
392 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
393 "clocks_in_mhz=1" is automatically included in the
396 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
398 When transfering memsize parameter to linux, some versions
399 expect it to be in bytes, others in MB.
400 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
404 New kernel versions are expecting firmware settings to be
405 passed using flat open firmware trees.
406 The environment variable "disable_of", when set, disables this
409 CONFIG_OF_FLAT_TREE_MAX_SIZE
411 The maximum size of the constructed OF tree.
413 OF_CPU - The proper name of the cpus node.
414 OF_TBCLK - The timebase frequency.
418 The resulting flat device tree will have a copy of the bd_t.
419 Space should be pre-allocated in the dts for the bd_t.
421 CONFIG_OF_HAS_UBOOT_ENV
423 The resulting flat device tree will have a copy of u-boot's
424 environment variables
426 CONFIG_OF_BOARD_SETUP
428 Board code has addition modification that it wants to make
429 to the flat device tree before handing it off to the kernel
434 Define this if you want support for Amba PrimeCell PL010 UARTs.
438 Define this if you want support for Amba PrimeCell PL011 UARTs.
442 If you have Amba PrimeCell PL011 UARTs, set this variable to
443 the clock speed of the UARTs.
447 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
448 define this to a list of base addresses for each (supported)
449 port. See e.g. include/configs/versatile.h
453 Depending on board, define exactly one serial port
454 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
455 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
456 console by defining CONFIG_8xx_CONS_NONE
458 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
459 port routines must be defined elsewhere
460 (i.e. serial_init(), serial_getc(), ...)
463 Enables console device for a color framebuffer. Needs following
464 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
465 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
467 VIDEO_HW_RECTFILL graphic chip supports
470 VIDEO_HW_BITBLT graphic chip supports
471 bit-blit (cf. smiLynxEM)
472 VIDEO_VISIBLE_COLS visible pixel columns
474 VIDEO_VISIBLE_ROWS visible pixel rows
475 VIDEO_PIXEL_SIZE bytes per pixel
476 VIDEO_DATA_FORMAT graphic data format
477 (0-5, cf. cfb_console.c)
478 VIDEO_FB_ADRS framebuffer address
479 VIDEO_KBD_INIT_FCT keyboard int fct
480 (i.e. i8042_kbd_init())
481 VIDEO_TSTC_FCT test char fct
483 VIDEO_GETC_FCT get char fct
485 CONFIG_CONSOLE_CURSOR cursor drawing on/off
486 (requires blink timer
488 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
489 CONFIG_CONSOLE_TIME display time/date info in
491 (requires CFG_CMD_DATE)
492 CONFIG_VIDEO_LOGO display Linux logo in
494 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
495 linux_logo.h for logo.
496 Requires CONFIG_VIDEO_LOGO
497 CONFIG_CONSOLE_EXTRA_INFO
498 addional board info beside
501 When CONFIG_CFB_CONSOLE is defined, video console is
502 default i/o. Serial console can be forced with
503 environment 'console=serial'.
505 When CONFIG_SILENT_CONSOLE is defined, all console
506 messages (by U-Boot and Linux!) can be silenced with
507 the "silent" environment variable. See
508 doc/README.silent for more information.
511 CONFIG_BAUDRATE - in bps
512 Select one of the baudrates listed in
513 CFG_BAUDRATE_TABLE, see below.
514 CFG_BRGCLK_PRESCALE, baudrate prescale
516 - Interrupt driven serial port input:
517 CONFIG_SERIAL_SOFTWARE_FIFO
520 Use an interrupt handler for receiving data on the
521 serial port. It also enables using hardware handshake
522 (RTS/CTS) and UART's built-in FIFO. Set the number of
523 bytes the interrupt driven input buffer should have.
525 Leave undefined to disable this feature, including
526 disable the buffer and hardware handshake.
528 - Console UART Number:
532 If defined internal UART1 (and not UART0) is used
533 as default U-Boot console.
535 - Boot Delay: CONFIG_BOOTDELAY - in seconds
536 Delay before automatically booting the default image;
537 set to -1 to disable autoboot.
539 See doc/README.autoboot for these options that
540 work with CONFIG_BOOTDELAY. None are required.
541 CONFIG_BOOT_RETRY_TIME
542 CONFIG_BOOT_RETRY_MIN
543 CONFIG_AUTOBOOT_KEYED
544 CONFIG_AUTOBOOT_PROMPT
545 CONFIG_AUTOBOOT_DELAY_STR
546 CONFIG_AUTOBOOT_STOP_STR
547 CONFIG_AUTOBOOT_DELAY_STR2
548 CONFIG_AUTOBOOT_STOP_STR2
549 CONFIG_ZERO_BOOTDELAY_CHECK
550 CONFIG_RESET_TO_RETRY
554 Only needed when CONFIG_BOOTDELAY is enabled;
555 define a command string that is automatically executed
556 when no character is read on the console interface
557 within "Boot Delay" after reset.
560 This can be used to pass arguments to the bootm
561 command. The value of CONFIG_BOOTARGS goes into the
562 environment value "bootargs".
564 CONFIG_RAMBOOT and CONFIG_NFSBOOT
565 The value of these goes into the environment as
566 "ramboot" and "nfsboot" respectively, and can be used
567 as a convenience, when switching between booting from
573 When this option is #defined, the existence of the
574 environment variable "preboot" will be checked
575 immediately before starting the CONFIG_BOOTDELAY
576 countdown and/or running the auto-boot command resp.
577 entering interactive mode.
579 This feature is especially useful when "preboot" is
580 automatically generated or modified. For an example
581 see the LWMON board specific code: here "preboot" is
582 modified when the user holds down a certain
583 combination of keys on the (special) keyboard when
586 - Serial Download Echo Mode:
588 If defined to 1, all characters received during a
589 serial download (using the "loads" command) are
590 echoed back. This might be needed by some terminal
591 emulations (like "cu"), but may as well just take
592 time on others. This setting #define's the initial
593 value of the "loads_echo" environment variable.
595 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
597 Select one of the baudrates listed in
598 CFG_BAUDRATE_TABLE, see below.
602 Most monitor functions can be selected (or
603 de-selected) by adjusting the definition of
604 CONFIG_COMMANDS; to select individual functions,
605 #define CONFIG_COMMANDS by "OR"ing any of the
608 #define enables commands:
609 -------------------------
610 CFG_CMD_ASKENV * ask for env variable
611 CFG_CMD_AUTOSCRIPT Autoscript Support
613 CFG_CMD_BEDBUG * Include BedBug Debugger
614 CFG_CMD_BMP * BMP support
615 CFG_CMD_BSP * Board specific commands
617 CFG_CMD_CACHE * icache, dcache
618 CFG_CMD_CONSOLE coninfo
619 CFG_CMD_DATE * support for RTC, date/time...
620 CFG_CMD_DHCP * DHCP support
621 CFG_CMD_DIAG * Diagnostics
622 CFG_CMD_DOC * Disk-On-Chip Support
623 CFG_CMD_DTT * Digital Therm and Thermostat
624 CFG_CMD_ECHO * echo arguments
625 CFG_CMD_EEPROM * EEPROM read/write support
626 CFG_CMD_ELF * bootelf, bootvx
628 CFG_CMD_FDC * Floppy Disk Support
629 CFG_CMD_FAT * FAT partition support
630 CFG_CMD_FDOS * Dos diskette Support
631 CFG_CMD_FLASH flinfo, erase, protect
632 CFG_CMD_FPGA FPGA device initialization support
633 CFG_CMD_HWFLOW * RTS/CTS hw flow control
634 CFG_CMD_I2C * I2C serial bus support
635 CFG_CMD_IDE * IDE harddisk support
637 CFG_CMD_IMLS List all found images
638 CFG_CMD_IMMAP * IMMR dump support
639 CFG_CMD_IRQ * irqinfo
640 CFG_CMD_ITEST Integer/string test of 2 values
641 CFG_CMD_JFFS2 * JFFS2 Support
645 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
647 CFG_CMD_MISC Misc functions like sleep etc
648 CFG_CMD_MMC * MMC memory mapped support
649 CFG_CMD_MII * MII utility commands
650 CFG_CMD_NAND * NAND support
651 CFG_CMD_NET bootp, tftpboot, rarpboot
652 CFG_CMD_PCI * pciinfo
653 CFG_CMD_PCMCIA * PCMCIA support
654 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
655 CFG_CMD_PORTIO * Port I/O
656 CFG_CMD_REGINFO * Register dump
657 CFG_CMD_RUN run command in env variable
658 CFG_CMD_SAVES * save S record dump
659 CFG_CMD_SCSI * SCSI Support
660 CFG_CMD_SDRAM * print SDRAM configuration information
661 (requires CFG_CMD_I2C)
662 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
663 CFG_CMD_SPI * SPI serial bus support
664 CFG_CMD_USB * USB support
665 CFG_CMD_VFD * VFD support (TRAB)
666 CFG_CMD_BSP * Board SPecific functions
667 CFG_CMD_CDP * Cisco Discover Protocol support
668 -----------------------------------------------
671 CONFIG_CMD_DFL Default configuration; at the moment
672 this is includes all commands, except
673 the ones marked with "*" in the list
676 If you don't define CONFIG_COMMANDS it defaults to
677 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
678 override the default settings in the respective
681 EXAMPLE: If you want all functions except of network
682 support you can write:
684 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
687 Note: Don't enable the "icache" and "dcache" commands
688 (configuration option CFG_CMD_CACHE) unless you know
689 what you (and your U-Boot users) are doing. Data
690 cache cannot be enabled on systems like the 8xx or
691 8260 (where accesses to the IMMR region must be
692 uncached), and it cannot be disabled on all other
693 systems where we (mis-) use the data cache to hold an
694 initial stack and some data.
697 XXX - this list needs to get updated!
701 If this variable is defined, it enables watchdog
702 support. There must be support in the platform specific
703 code for a watchdog. For the 8xx and 8260 CPUs, the
704 SIU Watchdog feature is enabled in the SYPCR
708 CONFIG_VERSION_VARIABLE
709 If this variable is defined, an environment variable
710 named "ver" is created by U-Boot showing the U-Boot
711 version as printed by the "version" command.
712 This variable is readonly.
716 When CFG_CMD_DATE is selected, the type of the RTC
717 has to be selected, too. Define exactly one of the
720 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
721 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
722 CONFIG_RTC_MC146818 - use MC146818 RTC
723 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
724 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
725 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
726 CONFIG_RTC_DS164x - use Dallas DS164x RTC
727 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
729 Note that if the RTC uses I2C, then the I2C interface
730 must also be configured. See I2C Support, below.
734 When CONFIG_TIMESTAMP is selected, the timestamp
735 (date and time) of an image is printed by image
736 commands like bootm or iminfo. This option is
737 automatically enabled when you select CFG_CMD_DATE .
740 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
741 and/or CONFIG_ISO_PARTITION
743 If IDE or SCSI support is enabled (CFG_CMD_IDE or
744 CFG_CMD_SCSI) you must configure support for at least
745 one partition type as well.
748 CONFIG_IDE_RESET_ROUTINE - this is defined in several
749 board configurations files but used nowhere!
751 CONFIG_IDE_RESET - is this is defined, IDE Reset will
752 be performed by calling the function
753 ide_set_reset(int reset)
754 which has to be defined in a board specific file
759 Set this to enable ATAPI support.
764 Set this to enable support for disks larger than 137GB
765 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
766 Whithout these , LBA48 support uses 32bit variables and will 'only'
767 support disks up to 2.1TB.
770 When enabled, makes the IDE subsystem use 64bit sector addresses.
774 At the moment only there is only support for the
775 SYM53C8XX SCSI controller; define
776 CONFIG_SCSI_SYM53C8XX to enable it.
778 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
779 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
780 CFG_SCSI_MAX_LUN] can be adjusted to define the
781 maximum numbers of LUNs, SCSI ID's and target
783 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
785 - NETWORK Support (PCI):
787 Support for Intel 8254x gigabit chips.
790 Support for Intel 82557/82559/82559ER chips.
791 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
792 write routine for first time initialisation.
795 Support for Digital 2114x chips.
796 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
797 modem chip initialisation (KS8761/QS6611).
800 Support for National dp83815 chips.
803 Support for National dp8382[01] gigabit chips.
805 - NETWORK Support (other):
807 CONFIG_DRIVER_LAN91C96
808 Support for SMSC's LAN91C96 chips.
811 Define this to hold the physical address
812 of the LAN91C96's I/O space
814 CONFIG_LAN91C96_USE_32_BIT
815 Define this to enable 32 bit addressing
817 CONFIG_DRIVER_SMC91111
818 Support for SMSC's LAN91C111 chip
821 Define this to hold the physical address
822 of the device (I/O space)
824 CONFIG_SMC_USE_32_BIT
825 Define this if data bus is 32 bits
827 CONFIG_SMC_USE_IOFUNCS
828 Define this to use i/o functions instead of macros
829 (some hardware wont work with macros)
832 At the moment only the UHCI host controller is
833 supported (PIP405, MIP405, MPC5200); define
834 CONFIG_USB_UHCI to enable it.
835 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
836 and define CONFIG_USB_STORAGE to enable the USB
839 Supported are USB Keyboards and USB Floppy drives
841 MPC5200 USB requires additional defines:
843 for 528 MHz Clock: 0x0001bbbb
845 for differential drivers: 0x00001000
846 for single ended drivers: 0x00005000
850 The MMC controller on the Intel PXA is supported. To
851 enable this define CONFIG_MMC. The MMC can be
852 accessed from the boot prompt by mapping the device
853 to physical memory similar to flash. Command line is
854 enabled with CFG_CMD_MMC. The MMC driver also works with
855 the FAT fs. This is enabled with CFG_CMD_FAT.
857 - Journaling Flash filesystem support:
858 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
859 CONFIG_JFFS2_NAND_DEV
860 Define these for a default partition on a NAND device
862 CFG_JFFS2_FIRST_SECTOR,
863 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
864 Define these for a default partition on a NOR device
867 Define this to create an own partition. You have to provide a
868 function struct part_info* jffs2_part_info(int part_num)
870 If you define only one JFFS2 partition you may also want to
871 #define CFG_JFFS_SINGLE_PART 1
872 to disable the command chpart. This is the default when you
873 have not defined a custom partition
878 Define this to enable standard (PC-Style) keyboard
882 Standard PC keyboard driver with US (is default) and
883 GERMAN key layout (switch via environment 'keymap=de') support.
884 Export function i8042_kbd_init, i8042_tstc and i8042_getc
885 for cfb_console. Supports cursor blinking.
890 Define this to enable video support (for output to
895 Enable Chips & Technologies 69000 Video chip
897 CONFIG_VIDEO_SMI_LYNXEM
898 Enable Silicon Motion SMI 712/710/810 Video chip. The
899 video output is selected via environment 'videoout'
900 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
903 For the CT69000 and SMI_LYNXEM drivers, videomode is
904 selected via environment 'videomode'. Two diferent ways
906 - "videomode=num" 'num' is a standard LiLo mode numbers.
907 Following standard modes are supported (* is default):
909 Colors 640x480 800x600 1024x768 1152x864 1280x1024
910 -------------+---------------------------------------------
911 8 bits | 0x301* 0x303 0x305 0x161 0x307
912 15 bits | 0x310 0x313 0x316 0x162 0x319
913 16 bits | 0x311 0x314 0x317 0x163 0x31A
914 24 bits | 0x312 0x315 0x318 ? 0x31B
915 -------------+---------------------------------------------
916 (i.e. setenv videomode 317; saveenv; reset;)
918 - "videomode=bootargs" all the video parameters are parsed
919 from the bootargs. (See drivers/videomodes.c)
922 CONFIG_VIDEO_SED13806
923 Enable Epson SED13806 driver. This driver supports 8bpp
924 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
925 or CONFIG_VIDEO_SED13806_16BPP
930 Define this to enable a custom keyboard support.
931 This simply calls drv_keyboard_init() which must be
932 defined in your board-specific files.
933 The only board using this so far is RBC823.
935 - LCD Support: CONFIG_LCD
937 Define this to enable LCD support (for output to LCD
938 display); also select one of the supported displays
939 by defining one of these:
941 CONFIG_NEC_NL6448AC33:
943 NEC NL6448AC33-18. Active, color, single scan.
945 CONFIG_NEC_NL6448BC20
947 NEC NL6448BC20-08. 6.5", 640x480.
948 Active, color, single scan.
950 CONFIG_NEC_NL6448BC33_54
952 NEC NL6448BC33-54. 10.4", 640x480.
953 Active, color, single scan.
957 Sharp 320x240. Active, color, single scan.
958 It isn't 16x9, and I am not sure what it is.
960 CONFIG_SHARP_LQ64D341
962 Sharp LQ64D341 display, 640x480.
963 Active, color, single scan.
967 HLD1045 display, 640x480.
968 Active, color, single scan.
972 Optrex CBL50840-2 NF-FW 99 22 M5
974 Hitachi LMG6912RPFC-00T
978 320x240. Black & white.
980 Normally display is black on white background; define
981 CFG_WHITE_ON_BLACK to get it inverted.
983 - Splash Screen Support: CONFIG_SPLASH_SCREEN
985 If this option is set, the environment is checked for
986 a variable "splashimage". If found, the usual display
987 of logo, copyright and system information on the LCD
988 is suppressed and the BMP image at the address
989 specified in "splashimage" is loaded instead. The
990 console is redirected to the "nulldev", too. This
991 allows for a "silent" boot where a splash screen is
992 loaded very quickly after power-on.
994 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
996 If this option is set, additionally to standard BMP
997 images, gzipped BMP images can be displayed via the
998 splashscreen support or the bmp command.
1000 - Compression support:
1003 If this option is set, support for bzip2 compressed
1004 images is included. If not, only uncompressed and gzip
1005 compressed images are supported.
1007 NOTE: the bzip2 algorithm requires a lot of RAM, so
1008 the malloc area (as defined by CFG_MALLOC_LEN) should
1014 The address of PHY on MII bus.
1016 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1018 The clock frequency of the MII bus
1022 If this option is set, support for speed/duplex
1023 detection of Gigabit PHY is included.
1025 CONFIG_PHY_RESET_DELAY
1027 Some PHY like Intel LXT971A need extra delay after
1028 reset before any MII register access is possible.
1029 For such PHY, set this option to the usec delay
1030 required. (minimum 300usec for LXT971A)
1032 CONFIG_PHY_CMD_DELAY (ppc4xx)
1034 Some PHY like Intel LXT971A need extra delay after
1035 command issued before MII status register can be read
1042 Define a default value for ethernet address to use
1043 for the respective ethernet interface, in case this
1044 is not determined automatically.
1049 Define a default value for the IP address to use for
1050 the default ethernet interface, in case this is not
1051 determined through e.g. bootp.
1053 - Server IP address:
1056 Defines a default value for theIP address of a TFTP
1057 server to contact when using the "tftboot" command.
1059 - BOOTP Recovery Mode:
1060 CONFIG_BOOTP_RANDOM_DELAY
1062 If you have many targets in a network that try to
1063 boot using BOOTP, you may want to avoid that all
1064 systems send out BOOTP requests at precisely the same
1065 moment (which would happen for instance at recovery
1066 from a power failure, when all systems will try to
1067 boot, thus flooding the BOOTP server. Defining
1068 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1069 inserted before sending out BOOTP requests. The
1070 following delays are insterted then:
1072 1st BOOTP request: delay 0 ... 1 sec
1073 2nd BOOTP request: delay 0 ... 2 sec
1074 3rd BOOTP request: delay 0 ... 4 sec
1076 BOOTP requests: delay 0 ... 8 sec
1078 - DHCP Advanced Options:
1081 You can fine tune the DHCP functionality by adding
1082 these flags to the CONFIG_BOOTP_MASK define:
1084 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1085 serverip from a DHCP server, it is possible that more
1086 than one DNS serverip is offered to the client.
1087 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1088 serverip will be stored in the additional environment
1089 variable "dnsip2". The first DNS serverip is always
1090 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1091 is added to the CONFIG_BOOTP_MASK.
1093 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1094 to do a dynamic update of a DNS server. To do this, they
1095 need the hostname of the DHCP requester.
1096 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1097 CONFIG_BOOTP_MASK, the content of the "hostname"
1098 environment variable is passed as option 12 to
1102 CONFIG_CDP_DEVICE_ID
1104 The device id used in CDP trigger frames.
1106 CONFIG_CDP_DEVICE_ID_PREFIX
1108 A two character string which is prefixed to the MAC address
1113 A printf format string which contains the ascii name of
1114 the port. Normally is set to "eth%d" which sets
1115 eth0 for the first ethernet, eth1 for the second etc.
1117 CONFIG_CDP_CAPABILITIES
1119 A 32bit integer which indicates the device capabilities;
1120 0x00000010 for a normal host which does not forwards.
1124 An ascii string containing the version of the software.
1128 An ascii string containing the name of the platform.
1132 A 32bit integer sent on the trigger.
1134 CONFIG_CDP_POWER_CONSUMPTION
1136 A 16bit integer containing the power consumption of the
1137 device in .1 of milliwatts.
1139 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1141 A byte containing the id of the VLAN.
1143 - Status LED: CONFIG_STATUS_LED
1145 Several configurations allow to display the current
1146 status using a LED. For instance, the LED will blink
1147 fast while running U-Boot code, stop blinking as
1148 soon as a reply to a BOOTP request was received, and
1149 start blinking slow once the Linux kernel is running
1150 (supported by a status LED driver in the Linux
1151 kernel). Defining CONFIG_STATUS_LED enables this
1154 - CAN Support: CONFIG_CAN_DRIVER
1156 Defining CONFIG_CAN_DRIVER enables CAN driver support
1157 on those systems that support this (optional)
1158 feature, like the TQM8xxL modules.
1160 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1162 These enable I2C serial bus commands. Defining either of
1163 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1164 include the appropriate I2C driver for the selected cpu.
1166 This will allow you to use i2c commands at the u-boot
1167 command line (as long as you set CFG_CMD_I2C in
1168 CONFIG_COMMANDS) and communicate with i2c based realtime
1169 clock chips. See common/cmd_i2c.c for a description of the
1170 command line interface.
1172 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1174 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1175 bit-banging) driver instead of CPM or similar hardware
1178 There are several other quantities that must also be
1179 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1181 In both cases you will need to define CFG_I2C_SPEED
1182 to be the frequency (in Hz) at which you wish your i2c bus
1183 to run and CFG_I2C_SLAVE to be the address of this node (ie
1184 the cpu's i2c node address).
1186 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1187 sets the cpu up as a master node and so its address should
1188 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1189 p.16-473). So, set CFG_I2C_SLAVE to 0.
1191 That's all that's required for CONFIG_HARD_I2C.
1193 If you use the software i2c interface (CONFIG_SOFT_I2C)
1194 then the following macros need to be defined (examples are
1195 from include/configs/lwmon.h):
1199 (Optional). Any commands necessary to enable the I2C
1200 controller or configure ports.
1202 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1206 (Only for MPC8260 CPU). The I/O port to use (the code
1207 assumes both bits are on the same port). Valid values
1208 are 0..3 for ports A..D.
1212 The code necessary to make the I2C data line active
1213 (driven). If the data line is open collector, this
1216 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1220 The code necessary to make the I2C data line tri-stated
1221 (inactive). If the data line is open collector, this
1224 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1228 Code that returns TRUE if the I2C data line is high,
1231 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1235 If <bit> is TRUE, sets the I2C data line high. If it
1236 is FALSE, it clears it (low).
1238 eg: #define I2C_SDA(bit) \
1239 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1240 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1244 If <bit> is TRUE, sets the I2C clock line high. If it
1245 is FALSE, it clears it (low).
1247 eg: #define I2C_SCL(bit) \
1248 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1249 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1253 This delay is invoked four times per clock cycle so this
1254 controls the rate of data transfer. The data rate thus
1255 is 1 / (I2C_DELAY * 4). Often defined to be something
1258 #define I2C_DELAY udelay(2)
1262 When a board is reset during an i2c bus transfer
1263 chips might think that the current transfer is still
1264 in progress. On some boards it is possible to access
1265 the i2c SCLK line directly, either by using the
1266 processor pin as a GPIO or by having a second pin
1267 connected to the bus. If this option is defined a
1268 custom i2c_init_board() routine in boards/xxx/board.c
1269 is run early in the boot sequence.
1271 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1273 This option enables configuration of bi_iic_fast[] flags
1274 in u-boot bd_info structure based on u-boot environment
1275 variable "i2cfast". (see also i2cfast)
1277 - SPI Support: CONFIG_SPI
1279 Enables SPI driver (so far only tested with
1280 SPI EEPROM, also an instance works with Crystal A/D and
1281 D/As on the SACSng board)
1285 Enables extended (16-bit) SPI EEPROM addressing.
1286 (symmetrical to CONFIG_I2C_X)
1290 Enables a software (bit-bang) SPI driver rather than
1291 using hardware support. This is a general purpose
1292 driver that only requires three general I/O port pins
1293 (two outputs, one input) to function. If this is
1294 defined, the board configuration must define several
1295 SPI configuration items (port pins to use, etc). For
1296 an example, see include/configs/sacsng.h.
1298 - FPGA Support: CONFIG_FPGA_COUNT
1300 Specify the number of FPGA devices to support.
1304 Used to specify the types of FPGA devices. For example,
1305 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1307 CFG_FPGA_PROG_FEEDBACK
1309 Enable printing of hash marks during FPGA configuration.
1313 Enable checks on FPGA configuration interface busy
1314 status by the configuration function. This option
1315 will require a board or device specific function to
1320 If defined, a function that provides delays in the FPGA
1321 configuration driver.
1323 CFG_FPGA_CHECK_CTRLC
1324 Allow Control-C to interrupt FPGA configuration
1326 CFG_FPGA_CHECK_ERROR
1328 Check for configuration errors during FPGA bitfile
1329 loading. For example, abort during Virtex II
1330 configuration if the INIT_B line goes low (which
1331 indicated a CRC error).
1335 Maximum time to wait for the INIT_B line to deassert
1336 after PROB_B has been deasserted during a Virtex II
1337 FPGA configuration sequence. The default time is 500
1342 Maximum time to wait for BUSY to deassert during
1343 Virtex II FPGA configuration. The default is 5 mS.
1345 CFG_FPGA_WAIT_CONFIG
1347 Time to wait after FPGA configuration. The default is
1350 - Configuration Management:
1353 If defined, this string will be added to the U-Boot
1354 version information (U_BOOT_VERSION)
1356 - Vendor Parameter Protection:
1358 U-Boot considers the values of the environment
1359 variables "serial#" (Board Serial Number) and
1360 "ethaddr" (Ethernet Address) to be parameters that
1361 are set once by the board vendor / manufacturer, and
1362 protects these variables from casual modification by
1363 the user. Once set, these variables are read-only,
1364 and write or delete attempts are rejected. You can
1365 change this behviour:
1367 If CONFIG_ENV_OVERWRITE is #defined in your config
1368 file, the write protection for vendor parameters is
1369 completely disabled. Anybody can change or delete
1372 Alternatively, if you #define _both_ CONFIG_ETHADDR
1373 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1374 ethernet address is installed in the environment,
1375 which can be changed exactly ONCE by the user. [The
1376 serial# is unaffected by this, i. e. it remains
1382 Define this variable to enable the reservation of
1383 "protected RAM", i. e. RAM which is not overwritten
1384 by U-Boot. Define CONFIG_PRAM to hold the number of
1385 kB you want to reserve for pRAM. You can overwrite
1386 this default value by defining an environment
1387 variable "pram" to the number of kB you want to
1388 reserve. Note that the board info structure will
1389 still show the full amount of RAM. If pRAM is
1390 reserved, a new environment variable "mem" will
1391 automatically be defined to hold the amount of
1392 remaining RAM in a form that can be passed as boot
1393 argument to Linux, for instance like that:
1395 setenv bootargs ... mem=\${mem}
1398 This way you can tell Linux not to use this memory,
1399 either, which results in a memory region that will
1400 not be affected by reboots.
1402 *WARNING* If your board configuration uses automatic
1403 detection of the RAM size, you must make sure that
1404 this memory test is non-destructive. So far, the
1405 following board configurations are known to be
1408 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1409 HERMES, IP860, RPXlite, LWMON, LANTEC,
1410 PCU_E, FLAGADM, TQM8260
1415 Define this variable to stop the system in case of a
1416 fatal error, so that you have to reset it manually.
1417 This is probably NOT a good idea for an embedded
1418 system where you want to system to reboot
1419 automatically as fast as possible, but it may be
1420 useful during development since you can try to debug
1421 the conditions that lead to the situation.
1423 CONFIG_NET_RETRY_COUNT
1425 This variable defines the number of retries for
1426 network operations like ARP, RARP, TFTP, or BOOTP
1427 before giving up the operation. If not defined, a
1428 default value of 5 is used.
1430 - Command Interpreter:
1433 Enable auto completion of commands using TAB.
1437 Define this variable to enable the "hush" shell (from
1438 Busybox) as command line interpreter, thus enabling
1439 powerful command line syntax like
1440 if...then...else...fi conditionals or `&&' and '||'
1441 constructs ("shell scripts").
1443 If undefined, you get the old, much simpler behaviour
1444 with a somewhat smaller memory footprint.
1449 This defines the secondary prompt string, which is
1450 printed when the command interpreter needs more input
1451 to complete a command. Usually "> ".
1455 In the current implementation, the local variables
1456 space and global environment variables space are
1457 separated. Local variables are those you define by
1458 simply typing `name=value'. To access a local
1459 variable later on, you have write `$name' or
1460 `${name}'; to execute the contents of a variable
1461 directly type `$name' at the command prompt.
1463 Global environment variables are those you use
1464 setenv/printenv to work with. To run a command stored
1465 in such a variable, you need to use the run command,
1466 and you must not use the '$' sign to access them.
1468 To store commands and special characters in a
1469 variable, please use double quotation marks
1470 surrounding the whole text of the variable, instead
1471 of the backslashes before semicolons and special
1474 - Default Environment:
1475 CONFIG_EXTRA_ENV_SETTINGS
1477 Define this to contain any number of null terminated
1478 strings (variable = value pairs) that will be part of
1479 the default environment compiled into the boot image.
1481 For example, place something like this in your
1482 board's config file:
1484 #define CONFIG_EXTRA_ENV_SETTINGS \
1488 Warning: This method is based on knowledge about the
1489 internal format how the environment is stored by the
1490 U-Boot code. This is NOT an official, exported
1491 interface! Although it is unlikely that this format
1492 will change soon, there is no guarantee either.
1493 You better know what you are doing here.
1495 Note: overly (ab)use of the default environment is
1496 discouraged. Make sure to check other ways to preset
1497 the environment like the autoscript function or the
1500 - DataFlash Support:
1501 CONFIG_HAS_DATAFLASH
1503 Defining this option enables DataFlash features and
1504 allows to read/write in Dataflash via the standard
1507 - SystemACE Support:
1510 Adding this option adds support for Xilinx SystemACE
1511 chips attached via some sort of local bus. The address
1512 of the chip must alsh be defined in the
1513 CFG_SYSTEMACE_BASE macro. For example:
1515 #define CONFIG_SYSTEMACE
1516 #define CFG_SYSTEMACE_BASE 0xf0000000
1518 When SystemACE support is added, the "ace" device type
1519 becomes available to the fat commands, i.e. fatls.
1521 - TFTP Fixed UDP Port:
1524 If this is defined, the environment variable tftpsrcp
1525 is used to supply the TFTP UDP source port value.
1526 If tftpsrcp isn't defined, the normal pseudo-random port
1527 number generator is used.
1529 Also, the environment variable tftpdstp is used to supply
1530 the TFTP UDP destination port value. If tftpdstp isn't
1531 defined, the normal port 69 is used.
1533 The purpose for tftpsrcp is to allow a TFTP server to
1534 blindly start the TFTP transfer using the pre-configured
1535 target IP address and UDP port. This has the effect of
1536 "punching through" the (Windows XP) firewall, allowing
1537 the remainder of the TFTP transfer to proceed normally.
1538 A better solution is to properly configure the firewall,
1539 but sometimes that is not allowed.
1541 - Show boot progress:
1542 CONFIG_SHOW_BOOT_PROGRESS
1544 Defining this option allows to add some board-
1545 specific code (calling a user-provided function
1546 "show_boot_progress(int)") that enables you to show
1547 the system's boot progress on some display (for
1548 example, some LED's) on your board. At the moment,
1549 the following checkpoints are implemented:
1552 1 common/cmd_bootm.c before attempting to boot an image
1553 -1 common/cmd_bootm.c Image header has bad magic number
1554 2 common/cmd_bootm.c Image header has correct magic number
1555 -2 common/cmd_bootm.c Image header has bad checksum
1556 3 common/cmd_bootm.c Image header has correct checksum
1557 -3 common/cmd_bootm.c Image data has bad checksum
1558 4 common/cmd_bootm.c Image data has correct checksum
1559 -4 common/cmd_bootm.c Image is for unsupported architecture
1560 5 common/cmd_bootm.c Architecture check OK
1561 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1562 6 common/cmd_bootm.c Image Type check OK
1563 -6 common/cmd_bootm.c gunzip uncompression error
1564 -7 common/cmd_bootm.c Unimplemented compression type
1565 7 common/cmd_bootm.c Uncompression OK
1566 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1567 8 common/cmd_bootm.c Image Type check OK
1568 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1569 9 common/cmd_bootm.c Start initial ramdisk verification
1570 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1571 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1572 10 common/cmd_bootm.c Ramdisk header is OK
1573 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1574 11 common/cmd_bootm.c Ramdisk data has correct checksum
1575 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1576 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1577 13 common/cmd_bootm.c Start multifile image verification
1578 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1579 15 common/cmd_bootm.c All preparation done, transferring control to OS
1581 -30 lib_ppc/board.c Fatal error, hang the system
1582 -31 post/post.c POST test failed, detected by post_output_backlog()
1583 -32 post/post.c POST test failed, detected by post_run_single()
1585 -1 common/cmd_doc.c Bad usage of "doc" command
1586 -1 common/cmd_doc.c No boot device
1587 -1 common/cmd_doc.c Unknown Chip ID on boot device
1588 -1 common/cmd_doc.c Read Error on boot device
1589 -1 common/cmd_doc.c Image header has bad magic number
1591 -1 common/cmd_ide.c Bad usage of "ide" command
1592 -1 common/cmd_ide.c No boot device
1593 -1 common/cmd_ide.c Unknown boot device
1594 -1 common/cmd_ide.c Unknown partition table
1595 -1 common/cmd_ide.c Invalid partition type
1596 -1 common/cmd_ide.c Read Error on boot device
1597 -1 common/cmd_ide.c Image header has bad magic number
1599 -1 common/cmd_nand.c Bad usage of "nand" command
1600 -1 common/cmd_nand.c No boot device
1601 -1 common/cmd_nand.c Unknown Chip ID on boot device
1602 -1 common/cmd_nand.c Read Error on boot device
1603 -1 common/cmd_nand.c Image header has bad magic number
1605 -1 common/env_common.c Environment has a bad CRC, using default
1611 [so far only for SMDK2400 and TRAB boards]
1613 - Modem support endable:
1614 CONFIG_MODEM_SUPPORT
1616 - RTS/CTS Flow control enable:
1619 - Modem debug support:
1620 CONFIG_MODEM_SUPPORT_DEBUG
1622 Enables debugging stuff (char screen[1024], dbg())
1623 for modem support. Useful only with BDI2000.
1625 - Interrupt support (PPC):
1627 There are common interrupt_init() and timer_interrupt()
1628 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1629 for cpu specific initialization. interrupt_init_cpu()
1630 should set decrementer_count to appropriate value. If
1631 cpu resets decrementer automatically after interrupt
1632 (ppc4xx) it should set decrementer_count to zero.
1633 timer_interrupt() calls timer_interrupt_cpu() for cpu
1634 specific handling. If board has watchdog / status_led
1635 / other_activity_monitor it works automatically from
1636 general timer_interrupt().
1640 In the target system modem support is enabled when a
1641 specific key (key combination) is pressed during
1642 power-on. Otherwise U-Boot will boot normally
1643 (autoboot). The key_pressed() fuction is called from
1644 board_init(). Currently key_pressed() is a dummy
1645 function, returning 1 and thus enabling modem
1648 If there are no modem init strings in the
1649 environment, U-Boot proceed to autoboot; the
1650 previous output (banner, info printfs) will be
1653 See also: doc/README.Modem
1656 Configuration Settings:
1657 -----------------------
1659 - CFG_LONGHELP: Defined when you want long help messages included;
1660 undefine this when you're short of memory.
1662 - CFG_PROMPT: This is what U-Boot prints on the console to
1663 prompt for user input.
1665 - CFG_CBSIZE: Buffer size for input from the Console
1667 - CFG_PBSIZE: Buffer size for Console output
1669 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1671 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1672 the application (usually a Linux kernel) when it is
1675 - CFG_BAUDRATE_TABLE:
1676 List of legal baudrate settings for this board.
1678 - CFG_CONSOLE_INFO_QUIET
1679 Suppress display of console information at boot.
1681 - CFG_CONSOLE_IS_IN_ENV
1682 If the board specific function
1683 extern int overwrite_console (void);
1684 returns 1, the stdin, stderr and stdout are switched to the
1685 serial port, else the settings in the environment are used.
1687 - CFG_CONSOLE_OVERWRITE_ROUTINE
1688 Enable the call to overwrite_console().
1690 - CFG_CONSOLE_ENV_OVERWRITE
1691 Enable overwrite of previous console environment settings.
1693 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1694 Begin and End addresses of the area used by the
1698 Enable an alternate, more extensive memory test.
1700 - CFG_MEMTEST_SCRATCH:
1701 Scratch address used by the alternate memory test
1702 You only need to set this if address zero isn't writeable
1704 - CFG_TFTP_LOADADDR:
1705 Default load address for network file downloads
1707 - CFG_LOADS_BAUD_CHANGE:
1708 Enable temporary baudrate change while serial download
1711 Physical start address of SDRAM. _Must_ be 0 here.
1714 Physical start address of Motherboard I/O (if using a
1718 Physical start address of Flash memory.
1721 Physical start address of boot monitor code (set by
1722 make config files to be same as the text base address
1723 (TEXT_BASE) used when linking) - same as
1724 CFG_FLASH_BASE when booting from flash.
1727 Size of memory reserved for monitor code, used to
1728 determine _at_compile_time_ (!) if the environment is
1729 embedded within the U-Boot image, or in a separate
1733 Size of DRAM reserved for malloc() use.
1736 Maximum size of memory mapped by the startup code of
1737 the Linux kernel; all data that must be processed by
1738 the Linux kernel (bd_info, boot arguments, eventually
1739 initrd image) must be put below this limit.
1741 - CFG_MAX_FLASH_BANKS:
1742 Max number of Flash memory banks
1744 - CFG_MAX_FLASH_SECT:
1745 Max number of sectors on a Flash chip
1747 - CFG_FLASH_ERASE_TOUT:
1748 Timeout for Flash erase operations (in ms)
1750 - CFG_FLASH_WRITE_TOUT:
1751 Timeout for Flash write operations (in ms)
1753 - CFG_FLASH_LOCK_TOUT
1754 Timeout for Flash set sector lock bit operation (in ms)
1756 - CFG_FLASH_UNLOCK_TOUT
1757 Timeout for Flash clear lock bits operation (in ms)
1759 - CFG_FLASH_PROTECTION
1760 If defined, hardware flash sectors protection is used
1761 instead of U-Boot software protection.
1763 - CFG_DIRECT_FLASH_TFTP:
1765 Enable TFTP transfers directly to flash memory;
1766 without this option such a download has to be
1767 performed in two steps: (1) download to RAM, and (2)
1768 copy from RAM to flash.
1770 The two-step approach is usually more reliable, since
1771 you can check if the download worked before you erase
1772 the flash, but in some situations (when sytem RAM is
1773 too limited to allow for a tempory copy of the
1774 downloaded image) this option may be very useful.
1777 Define if the flash driver uses extra elements in the
1778 common flash structure for storing flash geometry.
1780 - CFG_FLASH_CFI_DRIVER
1781 This option also enables the building of the cfi_flash driver
1782 in the drivers directory
1784 - CFG_FLASH_QUIET_TEST
1785 If this option is defined, the common CFI flash doesn't
1786 print it's warning upon not recognized FLASH banks. This
1787 is useful, if some of the configured banks are only
1788 optionally available.
1790 - CFG_RX_ETH_BUFFER:
1791 Defines the number of ethernet receive buffers. On some
1792 ethernet controllers it is recommended to set this value
1793 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1794 buffers can be full shortly after enabling the interface
1795 on high ethernet traffic.
1796 Defaults to 4 if not defined.
1798 The following definitions that deal with the placement and management
1799 of environment data (variable area); in general, we support the
1800 following configurations:
1802 - CFG_ENV_IS_IN_FLASH:
1804 Define this if the environment is in flash memory.
1806 a) The environment occupies one whole flash sector, which is
1807 "embedded" in the text segment with the U-Boot code. This
1808 happens usually with "bottom boot sector" or "top boot
1809 sector" type flash chips, which have several smaller
1810 sectors at the start or the end. For instance, such a
1811 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1812 such a case you would place the environment in one of the
1813 4 kB sectors - with U-Boot code before and after it. With
1814 "top boot sector" type flash chips, you would put the
1815 environment in one of the last sectors, leaving a gap
1816 between U-Boot and the environment.
1820 Offset of environment data (variable area) to the
1821 beginning of flash memory; for instance, with bottom boot
1822 type flash chips the second sector can be used: the offset
1823 for this sector is given here.
1825 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1829 This is just another way to specify the start address of
1830 the flash sector containing the environment (instead of
1833 - CFG_ENV_SECT_SIZE:
1835 Size of the sector containing the environment.
1838 b) Sometimes flash chips have few, equal sized, BIG sectors.
1839 In such a case you don't want to spend a whole sector for
1844 If you use this in combination with CFG_ENV_IS_IN_FLASH
1845 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1846 of this flash sector for the environment. This saves
1847 memory for the RAM copy of the environment.
1849 It may also save flash memory if you decide to use this
1850 when your environment is "embedded" within U-Boot code,
1851 since then the remainder of the flash sector could be used
1852 for U-Boot code. It should be pointed out that this is
1853 STRONGLY DISCOURAGED from a robustness point of view:
1854 updating the environment in flash makes it always
1855 necessary to erase the WHOLE sector. If something goes
1856 wrong before the contents has been restored from a copy in
1857 RAM, your target system will be dead.
1859 - CFG_ENV_ADDR_REDUND
1862 These settings describe a second storage area used to hold
1863 a redundand copy of the environment data, so that there is
1864 a valid backup copy in case there is a power failure during
1865 a "saveenv" operation.
1867 BE CAREFUL! Any changes to the flash layout, and some changes to the
1868 source code will make it necessary to adapt <board>/u-boot.lds*
1872 - CFG_ENV_IS_IN_NVRAM:
1874 Define this if you have some non-volatile memory device
1875 (NVRAM, battery buffered SRAM) which you want to use for the
1881 These two #defines are used to determin the memory area you
1882 want to use for environment. It is assumed that this memory
1883 can just be read and written to, without any special
1886 BE CAREFUL! The first access to the environment happens quite early
1887 in U-Boot initalization (when we try to get the setting of for the
1888 console baudrate). You *MUST* have mappend your NVRAM area then, or
1891 Please note that even with NVRAM we still use a copy of the
1892 environment in RAM: we could work on NVRAM directly, but we want to
1893 keep settings there always unmodified except somebody uses "saveenv"
1894 to save the current settings.
1897 - CFG_ENV_IS_IN_EEPROM:
1899 Use this if you have an EEPROM or similar serial access
1900 device and a driver for it.
1905 These two #defines specify the offset and size of the
1906 environment area within the total memory of your EEPROM.
1908 - CFG_I2C_EEPROM_ADDR:
1909 If defined, specified the chip address of the EEPROM device.
1910 The default address is zero.
1912 - CFG_EEPROM_PAGE_WRITE_BITS:
1913 If defined, the number of bits used to address bytes in a
1914 single page in the EEPROM device. A 64 byte page, for example
1915 would require six bits.
1917 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1918 If defined, the number of milliseconds to delay between
1919 page writes. The default is zero milliseconds.
1921 - CFG_I2C_EEPROM_ADDR_LEN:
1922 The length in bytes of the EEPROM memory array address. Note
1923 that this is NOT the chip address length!
1925 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1926 EEPROM chips that implement "address overflow" are ones
1927 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1928 address and the extra bits end up in the "chip address" bit
1929 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1932 Note that we consider the length of the address field to
1933 still be one byte because the extra address bits are hidden
1934 in the chip address.
1937 The size in bytes of the EEPROM device.
1940 - CFG_ENV_IS_IN_DATAFLASH:
1942 Define this if you have a DataFlash memory device which you
1943 want to use for the environment.
1949 These three #defines specify the offset and size of the
1950 environment area within the total memory of your DataFlash placed
1951 at the specified address.
1953 - CFG_ENV_IS_IN_NAND:
1955 Define this if you have a NAND device which you want to use
1956 for the environment.
1961 These two #defines specify the offset and size of the environment
1962 area within the first NAND device.
1964 - CFG_SPI_INIT_OFFSET
1966 Defines offset to the initial SPI buffer area in DPRAM. The
1967 area is used at an early stage (ROM part) if the environment
1968 is configured to reside in the SPI EEPROM: We need a 520 byte
1969 scratch DPRAM area. It is used between the two initialization
1970 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1971 to be a good choice since it makes it far enough from the
1972 start of the data area as well as from the stack pointer.
1974 Please note that the environment is read-only as long as the monitor
1975 has been relocated to RAM and a RAM copy of the environment has been
1976 created; also, when using EEPROM you will have to use getenv_r()
1977 until then to read environment variables.
1979 The environment is protected by a CRC32 checksum. Before the monitor
1980 is relocated into RAM, as a result of a bad CRC you will be working
1981 with the compiled-in default environment - *silently*!!! [This is
1982 necessary, because the first environment variable we need is the
1983 "baudrate" setting for the console - if we have a bad CRC, we don't
1984 have any device yet where we could complain.]
1986 Note: once the monitor has been relocated, then it will complain if
1987 the default environment is used; a new CRC is computed as soon as you
1988 use the "saveenv" command to store a valid environment.
1990 - CFG_FAULT_ECHO_LINK_DOWN:
1991 Echo the inverted Ethernet link state to the fault LED.
1993 Note: If this option is active, then CFG_FAULT_MII_ADDR
1994 also needs to be defined.
1996 - CFG_FAULT_MII_ADDR:
1997 MII address of the PHY to check for the Ethernet link state.
1999 - CFG_64BIT_VSPRINTF:
2000 Makes vsprintf (and all *printf functions) support printing
2001 of 64bit values by using the L quantifier
2003 - CFG_64BIT_STRTOUL:
2004 Adds simple_strtoull that returns a 64bit value
2006 Low Level (hardware related) configuration options:
2007 ---------------------------------------------------
2009 - CFG_CACHELINE_SIZE:
2010 Cache Line Size of the CPU.
2013 Default address of the IMMR after system reset.
2015 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2016 and RPXsuper) to be able to adjust the position of
2017 the IMMR register after a reset.
2019 - Floppy Disk Support:
2020 CFG_FDC_DRIVE_NUMBER
2022 the default drive number (default value 0)
2026 defines the spacing between fdc chipset registers
2031 defines the offset of register from address. It
2032 depends on which part of the data bus is connected to
2033 the fdc chipset. (default value 0)
2035 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2036 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2039 if CFG_FDC_HW_INIT is defined, then the function
2040 fdc_hw_init() is called at the beginning of the FDC
2041 setup. fdc_hw_init() must be provided by the board
2042 source code. It is used to make hardware dependant
2045 - CFG_IMMR: Physical address of the Internal Memory.
2046 DO NOT CHANGE unless you know exactly what you're
2047 doing! (11-4) [MPC8xx/82xx systems only]
2049 - CFG_INIT_RAM_ADDR:
2051 Start address of memory area that can be used for
2052 initial data and stack; please note that this must be
2053 writable memory that is working WITHOUT special
2054 initialization, i. e. you CANNOT use normal RAM which
2055 will become available only after programming the
2056 memory controller and running certain initialization
2059 U-Boot uses the following memory types:
2060 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2061 - MPC824X: data cache
2062 - PPC4xx: data cache
2064 - CFG_GBL_DATA_OFFSET:
2066 Offset of the initial data structure in the memory
2067 area defined by CFG_INIT_RAM_ADDR. Usually
2068 CFG_GBL_DATA_OFFSET is chosen such that the initial
2069 data is located at the end of the available space
2070 (sometimes written as (CFG_INIT_RAM_END -
2071 CFG_INIT_DATA_SIZE), and the initial stack is just
2072 below that area (growing from (CFG_INIT_RAM_ADDR +
2073 CFG_GBL_DATA_OFFSET) downward.
2076 On the MPC824X (or other systems that use the data
2077 cache for initial memory) the address chosen for
2078 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2079 point to an otherwise UNUSED address space between
2080 the top of RAM and the start of the PCI space.
2082 - CFG_SIUMCR: SIU Module Configuration (11-6)
2084 - CFG_SYPCR: System Protection Control (11-9)
2086 - CFG_TBSCR: Time Base Status and Control (11-26)
2088 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2090 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2092 - CFG_SCCR: System Clock and reset Control Register (15-27)
2094 - CFG_OR_TIMING_SDRAM:
2098 periodic timer for refresh
2100 - CFG_DER: Debug Event Register (37-47)
2102 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2103 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2104 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2106 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2108 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2109 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2110 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2111 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2113 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2114 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2115 Machine Mode Register and Memory Periodic Timer
2116 Prescaler definitions (SDRAM timing)
2118 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2119 enable I2C microcode relocation patch (MPC8xx);
2120 define relocation offset in DPRAM [DSP2]
2122 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2123 enable SPI microcode relocation patch (MPC8xx);
2124 define relocation offset in DPRAM [SCC4]
2127 Use OSCM clock mode on MBX8xx board. Be careful,
2128 wrong setting might damage your board. Read
2129 doc/README.MBX before setting this variable!
2131 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2132 Offset of the bootmode word in DPRAM used by post
2133 (Power On Self Tests). This definition overrides
2134 #define'd default value in commproc.h resp.
2137 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2138 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2139 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2140 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2141 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2142 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2143 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2144 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2145 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2147 - CONFIG_ETHER_ON_FEC[12]
2148 Define to enable FEC[12] on a 8xx series processor.
2150 - CONFIG_FEC[12]_PHY
2151 Define to the hardcoded PHY address which corresponds
2152 to the given FEC; i. e.
2153 #define CONFIG_FEC1_PHY 4
2154 means that the PHY with address 4 is connected to FEC1
2156 When set to -1, means to probe for first available.
2158 - CONFIG_FEC[12]_PHY_NORXERR
2159 The PHY does not have a RXERR line (RMII only).
2160 (so program the FEC to ignore it).
2163 Enable RMII mode for all FECs.
2164 Note that this is a global option, we can't
2165 have one FEC in standard MII mode and another in RMII mode.
2167 - CONFIG_CRC32_VERIFY
2168 Add a verify option to the crc32 command.
2171 => crc32 -v <address> <count> <crc32>
2173 Where address/count indicate a memory area
2174 and crc32 is the correct crc32 which the
2178 Add the "loopw" memory command. This only takes effect if
2179 the memory commands are activated globally (CFG_CMD_MEM).
2182 Add the "mdc" and "mwc" memory commands. These are cyclic
2187 This command will print 4 bytes (10,11,12,13) each 500 ms.
2189 => mwc.l 100 12345678 10
2190 This command will write 12345678 to address 100 all 10 ms.
2192 This only takes effect if the memory commands are activated
2193 globally (CFG_CMD_MEM).
2195 - CONFIG_SKIP_LOWLEVEL_INIT
2196 - CONFIG_SKIP_RELOCATE_UBOOT
2198 [ARM only] If these variables are defined, then
2199 certain low level initializations (like setting up
2200 the memory controller) are omitted and/or U-Boot does
2201 not relocate itself into RAM.
2202 Normally these variables MUST NOT be defined. The
2203 only exception is when U-Boot is loaded (to RAM) by
2204 some other boot loader or by a debugger which
2205 performs these intializations itself.
2208 Building the Software:
2209 ======================
2211 Building U-Boot has been tested in native PPC environments (on a
2212 PowerBook G3 running LinuxPPC 2000) and in cross environments
2213 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2216 If you are not using a native PPC environment, it is assumed that you
2217 have the GNU cross compiling tools available in your path and named
2218 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2219 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2220 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2223 CROSS_COMPILE = ppc_4xx-
2226 U-Boot is intended to be simple to build. After installing the
2227 sources you must configure U-Boot for one specific board type. This
2232 where "NAME_config" is the name of one of the existing
2233 configurations; the following names are supported:
2235 ADCIOP_config FPS860L_config omap730p2_config
2236 ADS860_config GEN860T_config pcu_e_config
2238 AR405_config GENIETV_config PIP405_config
2239 at91rm9200dk_config GTH_config QS823_config
2240 CANBT_config hermes_config QS850_config
2241 cmi_mpc5xx_config hymod_config QS860T_config
2242 cogent_common_config IP860_config RPXlite_config
2243 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2244 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2245 CPCI405_config JSE_config rsdproto_config
2246 CPCIISER4_config LANTEC_config Sandpoint8240_config
2247 csb272_config lwmon_config sbc8260_config
2248 CU824_config MBX860T_config sbc8560_33_config
2249 DUET_ADS_config MBX_config sbc8560_66_config
2250 EBONY_config MPC8260ADS_config SM850_config
2251 ELPT860_config MPC8540ADS_config SPD823TS_config
2252 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2253 ETX094_config MPC8560ADS_config SXNI855T_config
2254 FADS823_config NETVIA_config TQM823L_config
2255 FADS850SAR_config omap1510inn_config TQM850L_config
2256 FADS860T_config omap1610h2_config TQM855L_config
2257 FPS850L_config omap1610inn_config TQM860L_config
2258 omap5912osk_config walnut_config
2259 omap2420h4_config Yukon8220_config
2262 Note: for some board special configuration names may exist; check if
2263 additional information is available from the board vendor; for
2264 instance, the TQM823L systems are available without (standard)
2265 or with LCD support. You can select such additional "features"
2266 when chosing the configuration, i. e.
2269 - will configure for a plain TQM823L, i. e. no LCD support
2271 make TQM823L_LCD_config
2272 - will configure for a TQM823L with U-Boot console on LCD
2277 Finally, type "make all", and you should get some working U-Boot
2278 images ready for download to / installation on your system:
2280 - "u-boot.bin" is a raw binary image
2281 - "u-boot" is an image in ELF binary format
2282 - "u-boot.srec" is in Motorola S-Record format
2285 Please be aware that the Makefiles assume you are using GNU make, so
2286 for instance on NetBSD you might need to use "gmake" instead of
2290 If the system board that you have is not listed, then you will need
2291 to port U-Boot to your hardware platform. To do this, follow these
2294 1. Add a new configuration option for your board to the toplevel
2295 "Makefile" and to the "MAKEALL" script, using the existing
2296 entries as examples. Note that here and at many other places
2297 boards and other names are listed in alphabetical sort order. Please
2299 2. Create a new directory to hold your board specific code. Add any
2300 files you need. In your board directory, you will need at least
2301 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2302 3. Create a new configuration file "include/configs/<board>.h" for
2304 3. If you're porting U-Boot to a new CPU, then also create a new
2305 directory to hold your CPU specific code. Add any files you need.
2306 4. Run "make <board>_config" with your new name.
2307 5. Type "make", and you should get a working "u-boot.srec" file
2308 to be installed on your target system.
2309 6. Debug and solve any problems that might arise.
2310 [Of course, this last step is much harder than it sounds.]
2313 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2314 ==============================================================
2316 If you have modified U-Boot sources (for instance added a new board
2317 or support for new devices, a new CPU, etc.) you are expected to
2318 provide feedback to the other developers. The feedback normally takes
2319 the form of a "patch", i. e. a context diff against a certain (latest
2320 official or latest in CVS) version of U-Boot sources.
2322 But before you submit such a patch, please verify that your modifi-
2323 cation did not break existing code. At least make sure that *ALL* of
2324 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2325 just run the "MAKEALL" script, which will configure and build U-Boot
2326 for ALL supported system. Be warned, this will take a while. You can
2327 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2328 environment variable to the script, i. e. to use the cross tools from
2329 MontaVista's Hard Hat Linux you can type
2331 CROSS_COMPILE=ppc_8xx- MAKEALL
2333 or to build on a native PowerPC system you can type
2335 CROSS_COMPILE=' ' MAKEALL
2337 See also "U-Boot Porting Guide" below.
2340 Monitor Commands - Overview:
2341 ============================
2343 go - start application at address 'addr'
2344 run - run commands in an environment variable
2345 bootm - boot application image from memory
2346 bootp - boot image via network using BootP/TFTP protocol
2347 tftpboot- boot image via network using TFTP protocol
2348 and env variables "ipaddr" and "serverip"
2349 (and eventually "gatewayip")
2350 rarpboot- boot image via network using RARP/TFTP protocol
2351 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2352 loads - load S-Record file over serial line
2353 loadb - load binary file over serial line (kermit mode)
2355 mm - memory modify (auto-incrementing)
2356 nm - memory modify (constant address)
2357 mw - memory write (fill)
2359 cmp - memory compare
2360 crc32 - checksum calculation
2361 imd - i2c memory display
2362 imm - i2c memory modify (auto-incrementing)
2363 inm - i2c memory modify (constant address)
2364 imw - i2c memory write (fill)
2365 icrc32 - i2c checksum calculation
2366 iprobe - probe to discover valid I2C chip addresses
2367 iloop - infinite loop on address range
2368 isdram - print SDRAM configuration information
2369 sspi - SPI utility commands
2370 base - print or set address offset
2371 printenv- print environment variables
2372 setenv - set environment variables
2373 saveenv - save environment variables to persistent storage
2374 protect - enable or disable FLASH write protection
2375 erase - erase FLASH memory
2376 flinfo - print FLASH memory information
2377 bdinfo - print Board Info structure
2378 iminfo - print header information for application image
2379 coninfo - print console devices and informations
2380 ide - IDE sub-system
2381 loop - infinite loop on address range
2382 loopw - infinite write loop on address range
2383 mtest - simple RAM test
2384 icache - enable or disable instruction cache
2385 dcache - enable or disable data cache
2386 reset - Perform RESET of the CPU
2387 echo - echo args to console
2388 version - print monitor version
2389 help - print online help
2390 ? - alias for 'help'
2393 Monitor Commands - Detailed Description:
2394 ========================================
2398 For now: just type "help <command>".
2401 Environment Variables:
2402 ======================
2404 U-Boot supports user configuration using Environment Variables which
2405 can be made persistent by saving to Flash memory.
2407 Environment Variables are set using "setenv", printed using
2408 "printenv", and saved to Flash using "saveenv". Using "setenv"
2409 without a value can be used to delete a variable from the
2410 environment. As long as you don't save the environment you are
2411 working with an in-memory copy. In case the Flash area containing the
2412 environment is erased by accident, a default environment is provided.
2414 Some configuration options can be set using Environment Variables:
2416 baudrate - see CONFIG_BAUDRATE
2418 bootdelay - see CONFIG_BOOTDELAY
2420 bootcmd - see CONFIG_BOOTCOMMAND
2422 bootargs - Boot arguments when booting an RTOS image
2424 bootfile - Name of the image to load with TFTP
2426 autoload - if set to "no" (any string beginning with 'n'),
2427 "bootp" will just load perform a lookup of the
2428 configuration from the BOOTP server, but not try to
2429 load any image using TFTP
2431 autostart - if set to "yes", an image loaded using the "bootp",
2432 "rarpboot", "tftpboot" or "diskboot" commands will
2433 be automatically started (by internally calling
2436 If set to "no", a standalone image passed to the
2437 "bootm" command will be copied to the load address
2438 (and eventually uncompressed), but NOT be started.
2439 This can be used to load and uncompress arbitrary
2442 i2cfast - (PPC405GP|PPC405EP only)
2443 if set to 'y' configures Linux I2C driver for fast
2444 mode (400kHZ). This environment variable is used in
2445 initialization code. So, for changes to be effective
2446 it must be saved and board must be reset.
2448 initrd_high - restrict positioning of initrd images:
2449 If this variable is not set, initrd images will be
2450 copied to the highest possible address in RAM; this
2451 is usually what you want since it allows for
2452 maximum initrd size. If for some reason you want to
2453 make sure that the initrd image is loaded below the
2454 CFG_BOOTMAPSZ limit, you can set this environment
2455 variable to a value of "no" or "off" or "0".
2456 Alternatively, you can set it to a maximum upper
2457 address to use (U-Boot will still check that it
2458 does not overwrite the U-Boot stack and data).
2460 For instance, when you have a system with 16 MB
2461 RAM, and want to reserve 4 MB from use by Linux,
2462 you can do this by adding "mem=12M" to the value of
2463 the "bootargs" variable. However, now you must make
2464 sure that the initrd image is placed in the first
2465 12 MB as well - this can be done with
2467 setenv initrd_high 00c00000
2469 If you set initrd_high to 0xFFFFFFFF, this is an
2470 indication to U-Boot that all addresses are legal
2471 for the Linux kernel, including addresses in flash
2472 memory. In this case U-Boot will NOT COPY the
2473 ramdisk at all. This may be useful to reduce the
2474 boot time on your system, but requires that this
2475 feature is supported by your Linux kernel.
2477 ipaddr - IP address; needed for tftpboot command
2479 loadaddr - Default load address for commands like "bootp",
2480 "rarpboot", "tftpboot", "loadb" or "diskboot"
2482 loads_echo - see CONFIG_LOADS_ECHO
2484 serverip - TFTP server IP address; needed for tftpboot command
2486 bootretry - see CONFIG_BOOT_RETRY_TIME
2488 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2490 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2492 ethprime - When CONFIG_NET_MULTI is enabled controls which
2493 interface is used first.
2495 ethact - When CONFIG_NET_MULTI is enabled controls which
2496 interface is currently active. For example you
2497 can do the following
2499 => setenv ethact FEC ETHERNET
2500 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2501 => setenv ethact SCC ETHERNET
2502 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2504 netretry - When set to "no" each network operation will
2505 either succeed or fail without retrying.
2506 When set to "once" the network operation will
2507 fail when all the available network interfaces
2508 are tried once without success.
2509 Useful on scripts which control the retry operation
2512 tftpsrcport - If this is set, the value is used for TFTP's
2515 tftpdstport - If this is set, the value is used for TFTP's UDP
2516 destination port instead of the Well Know Port 69.
2518 vlan - When set to a value < 4095 the traffic over
2519 ethernet is encapsulated/received over 802.1q
2522 The following environment variables may be used and automatically
2523 updated by the network boot commands ("bootp" and "rarpboot"),
2524 depending the information provided by your boot server:
2526 bootfile - see above
2527 dnsip - IP address of your Domain Name Server
2528 dnsip2 - IP address of your secondary Domain Name Server
2529 gatewayip - IP address of the Gateway (Router) to use
2530 hostname - Target hostname
2532 netmask - Subnet Mask
2533 rootpath - Pathname of the root filesystem on the NFS server
2534 serverip - see above
2537 There are two special Environment Variables:
2539 serial# - contains hardware identification information such
2540 as type string and/or serial number
2541 ethaddr - Ethernet address
2543 These variables can be set only once (usually during manufacturing of
2544 the board). U-Boot refuses to delete or overwrite these variables
2545 once they have been set once.
2548 Further special Environment Variables:
2550 ver - Contains the U-Boot version string as printed
2551 with the "version" command. This variable is
2552 readonly (see CONFIG_VERSION_VARIABLE).
2555 Please note that changes to some configuration parameters may take
2556 only effect after the next boot (yes, that's just like Windoze :-).
2559 Command Line Parsing:
2560 =====================
2562 There are two different command line parsers available with U-Boot:
2563 the old "simple" one, and the much more powerful "hush" shell:
2565 Old, simple command line parser:
2566 --------------------------------
2568 - supports environment variables (through setenv / saveenv commands)
2569 - several commands on one line, separated by ';'
2570 - variable substitution using "... ${name} ..." syntax
2571 - special characters ('$', ';') can be escaped by prefixing with '\',
2573 setenv bootcmd bootm \${address}
2574 - You can also escape text by enclosing in single apostrophes, for example:
2575 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2580 - similar to Bourne shell, with control structures like
2581 if...then...else...fi, for...do...done; while...do...done,
2582 until...do...done, ...
2583 - supports environment ("global") variables (through setenv / saveenv
2584 commands) and local shell variables (through standard shell syntax
2585 "name=value"); only environment variables can be used with "run"
2591 (1) If a command line (or an environment variable executed by a "run"
2592 command) contains several commands separated by semicolon, and
2593 one of these commands fails, then the remaining commands will be
2596 (2) If you execute several variables with one call to run (i. e.
2597 calling run with a list af variables as arguments), any failing
2598 command will cause "run" to terminate, i. e. the remaining
2599 variables are not executed.
2601 Note for Redundant Ethernet Interfaces:
2602 =======================================
2604 Some boards come with redundant ethernet interfaces; U-Boot supports
2605 such configurations and is capable of automatic selection of a
2606 "working" interface when needed. MAC assignment works as follows:
2608 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2609 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2610 "eth1addr" (=>eth1), "eth2addr", ...
2612 If the network interface stores some valid MAC address (for instance
2613 in SROM), this is used as default address if there is NO correspon-
2614 ding setting in the environment; if the corresponding environment
2615 variable is set, this overrides the settings in the card; that means:
2617 o If the SROM has a valid MAC address, and there is no address in the
2618 environment, the SROM's address is used.
2620 o If there is no valid address in the SROM, and a definition in the
2621 environment exists, then the value from the environment variable is
2624 o If both the SROM and the environment contain a MAC address, and
2625 both addresses are the same, this MAC address is used.
2627 o If both the SROM and the environment contain a MAC address, and the
2628 addresses differ, the value from the environment is used and a
2631 o If neither SROM nor the environment contain a MAC address, an error
2638 The "boot" commands of this monitor operate on "image" files which
2639 can be basicly anything, preceeded by a special header; see the
2640 definitions in include/image.h for details; basicly, the header
2641 defines the following image properties:
2643 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2644 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2645 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2646 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2647 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2648 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2649 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2650 * Compression Type (uncompressed, gzip, bzip2)
2656 The header is marked by a special Magic Number, and both the header
2657 and the data portions of the image are secured against corruption by
2664 Although U-Boot should support any OS or standalone application
2665 easily, the main focus has always been on Linux during the design of
2668 U-Boot includes many features that so far have been part of some
2669 special "boot loader" code within the Linux kernel. Also, any
2670 "initrd" images to be used are no longer part of one big Linux image;
2671 instead, kernel and "initrd" are separate images. This implementation
2672 serves several purposes:
2674 - the same features can be used for other OS or standalone
2675 applications (for instance: using compressed images to reduce the
2676 Flash memory footprint)
2678 - it becomes much easier to port new Linux kernel versions because
2679 lots of low-level, hardware dependent stuff are done by U-Boot
2681 - the same Linux kernel image can now be used with different "initrd"
2682 images; of course this also means that different kernel images can
2683 be run with the same "initrd". This makes testing easier (you don't
2684 have to build a new "zImage.initrd" Linux image when you just
2685 change a file in your "initrd"). Also, a field-upgrade of the
2686 software is easier now.
2692 Porting Linux to U-Boot based systems:
2693 ---------------------------------------
2695 U-Boot cannot save you from doing all the necessary modifications to
2696 configure the Linux device drivers for use with your target hardware
2697 (no, we don't intend to provide a full virtual machine interface to
2700 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2702 Just make sure your machine specific header file (for instance
2703 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2704 Information structure as we define in include/u-boot.h, and make
2705 sure that your definition of IMAP_ADDR uses the same value as your
2706 U-Boot configuration in CFG_IMMR.
2709 Configuring the Linux kernel:
2710 -----------------------------
2712 No specific requirements for U-Boot. Make sure you have some root
2713 device (initial ramdisk, NFS) for your target system.
2716 Building a Linux Image:
2717 -----------------------
2719 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2720 not used. If you use recent kernel source, a new build target
2721 "uImage" will exist which automatically builds an image usable by
2722 U-Boot. Most older kernels also have support for a "pImage" target,
2723 which was introduced for our predecessor project PPCBoot and uses a
2724 100% compatible format.
2733 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2734 encapsulate a compressed Linux kernel image with header information,
2735 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2737 * build a standard "vmlinux" kernel image (in ELF binary format):
2739 * convert the kernel into a raw binary image:
2741 ${CROSS_COMPILE}-objcopy -O binary \
2742 -R .note -R .comment \
2743 -S vmlinux linux.bin
2745 * compress the binary image:
2749 * package compressed binary image for U-Boot:
2751 mkimage -A ppc -O linux -T kernel -C gzip \
2752 -a 0 -e 0 -n "Linux Kernel Image" \
2753 -d linux.bin.gz uImage
2756 The "mkimage" tool can also be used to create ramdisk images for use
2757 with U-Boot, either separated from the Linux kernel image, or
2758 combined into one file. "mkimage" encapsulates the images with a 64
2759 byte header containing information about target architecture,
2760 operating system, image type, compression method, entry points, time
2761 stamp, CRC32 checksums, etc.
2763 "mkimage" can be called in two ways: to verify existing images and
2764 print the header information, or to build new images.
2766 In the first form (with "-l" option) mkimage lists the information
2767 contained in the header of an existing U-Boot image; this includes
2768 checksum verification:
2770 tools/mkimage -l image
2771 -l ==> list image header information
2773 The second form (with "-d" option) is used to build a U-Boot image
2774 from a "data file" which is used as image payload:
2776 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2777 -n name -d data_file image
2778 -A ==> set architecture to 'arch'
2779 -O ==> set operating system to 'os'
2780 -T ==> set image type to 'type'
2781 -C ==> set compression type 'comp'
2782 -a ==> set load address to 'addr' (hex)
2783 -e ==> set entry point to 'ep' (hex)
2784 -n ==> set image name to 'name'
2785 -d ==> use image data from 'datafile'
2787 Right now, all Linux kernels for PowerPC systems use the same load
2788 address (0x00000000), but the entry point address depends on the
2791 - 2.2.x kernels have the entry point at 0x0000000C,
2792 - 2.3.x and later kernels have the entry point at 0x00000000.
2794 So a typical call to build a U-Boot image would read:
2796 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2797 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2798 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2799 > examples/uImage.TQM850L
2800 Image Name: 2.4.4 kernel for TQM850L
2801 Created: Wed Jul 19 02:34:59 2000
2802 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2803 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2804 Load Address: 0x00000000
2805 Entry Point: 0x00000000
2807 To verify the contents of the image (or check for corruption):
2809 -> tools/mkimage -l examples/uImage.TQM850L
2810 Image Name: 2.4.4 kernel for TQM850L
2811 Created: Wed Jul 19 02:34:59 2000
2812 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2813 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2814 Load Address: 0x00000000
2815 Entry Point: 0x00000000
2817 NOTE: for embedded systems where boot time is critical you can trade
2818 speed for memory and install an UNCOMPRESSED image instead: this
2819 needs more space in Flash, but boots much faster since it does not
2820 need to be uncompressed:
2822 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2823 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2824 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2825 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2826 > examples/uImage.TQM850L-uncompressed
2827 Image Name: 2.4.4 kernel for TQM850L
2828 Created: Wed Jul 19 02:34:59 2000
2829 Image Type: PowerPC Linux Kernel Image (uncompressed)
2830 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2831 Load Address: 0x00000000
2832 Entry Point: 0x00000000
2835 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2836 when your kernel is intended to use an initial ramdisk:
2838 -> tools/mkimage -n 'Simple Ramdisk Image' \
2839 > -A ppc -O linux -T ramdisk -C gzip \
2840 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2841 Image Name: Simple Ramdisk Image
2842 Created: Wed Jan 12 14:01:50 2000
2843 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2844 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2845 Load Address: 0x00000000
2846 Entry Point: 0x00000000
2849 Installing a Linux Image:
2850 -------------------------
2852 To downloading a U-Boot image over the serial (console) interface,
2853 you must convert the image to S-Record format:
2855 objcopy -I binary -O srec examples/image examples/image.srec
2857 The 'objcopy' does not understand the information in the U-Boot
2858 image header, so the resulting S-Record file will be relative to
2859 address 0x00000000. To load it to a given address, you need to
2860 specify the target address as 'offset' parameter with the 'loads'
2863 Example: install the image to address 0x40100000 (which on the
2864 TQM8xxL is in the first Flash bank):
2866 => erase 40100000 401FFFFF
2872 ## Ready for S-Record download ...
2873 ~>examples/image.srec
2874 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2876 15989 15990 15991 15992
2877 [file transfer complete]
2879 ## Start Addr = 0x00000000
2882 You can check the success of the download using the 'iminfo' command;
2883 this includes a checksum verification so you can be sure no data
2884 corruption happened:
2888 ## Checking Image at 40100000 ...
2889 Image Name: 2.2.13 for initrd on TQM850L
2890 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2891 Data Size: 335725 Bytes = 327 kB = 0 MB
2892 Load Address: 00000000
2893 Entry Point: 0000000c
2894 Verifying Checksum ... OK
2900 The "bootm" command is used to boot an application that is stored in
2901 memory (RAM or Flash). In case of a Linux kernel image, the contents
2902 of the "bootargs" environment variable is passed to the kernel as
2903 parameters. You can check and modify this variable using the
2904 "printenv" and "setenv" commands:
2907 => printenv bootargs
2908 bootargs=root=/dev/ram
2910 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2912 => printenv bootargs
2913 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2916 ## Booting Linux kernel at 40020000 ...
2917 Image Name: 2.2.13 for NFS on TQM850L
2918 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2919 Data Size: 381681 Bytes = 372 kB = 0 MB
2920 Load Address: 00000000
2921 Entry Point: 0000000c
2922 Verifying Checksum ... OK
2923 Uncompressing Kernel Image ... OK
2924 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
2925 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2926 time_init: decrementer frequency = 187500000/60
2927 Calibrating delay loop... 49.77 BogoMIPS
2928 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2931 If you want to boot a Linux kernel with initial ram disk, you pass
2932 the memory addresses of both the kernel and the initrd image (PPBCOOT
2933 format!) to the "bootm" command:
2935 => imi 40100000 40200000
2937 ## Checking Image at 40100000 ...
2938 Image Name: 2.2.13 for initrd on TQM850L
2939 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2940 Data Size: 335725 Bytes = 327 kB = 0 MB
2941 Load Address: 00000000
2942 Entry Point: 0000000c
2943 Verifying Checksum ... OK
2945 ## Checking Image at 40200000 ...
2946 Image Name: Simple Ramdisk Image
2947 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2948 Data Size: 566530 Bytes = 553 kB = 0 MB
2949 Load Address: 00000000
2950 Entry Point: 00000000
2951 Verifying Checksum ... OK
2953 => bootm 40100000 40200000
2954 ## Booting Linux kernel at 40100000 ...
2955 Image Name: 2.2.13 for initrd on TQM850L
2956 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2957 Data Size: 335725 Bytes = 327 kB = 0 MB
2958 Load Address: 00000000
2959 Entry Point: 0000000c
2960 Verifying Checksum ... OK
2961 Uncompressing Kernel Image ... OK
2962 ## Loading RAMDisk Image at 40200000 ...
2963 Image Name: Simple Ramdisk Image
2964 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2965 Data Size: 566530 Bytes = 553 kB = 0 MB
2966 Load Address: 00000000
2967 Entry Point: 00000000
2968 Verifying Checksum ... OK
2969 Loading Ramdisk ... OK
2970 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
2971 Boot arguments: root=/dev/ram
2972 time_init: decrementer frequency = 187500000/60
2973 Calibrating delay loop... 49.77 BogoMIPS
2975 RAMDISK: Compressed image found at block 0
2976 VFS: Mounted root (ext2 filesystem).
2980 More About U-Boot Image Types:
2981 ------------------------------
2983 U-Boot supports the following image types:
2985 "Standalone Programs" are directly runnable in the environment
2986 provided by U-Boot; it is expected that (if they behave
2987 well) you can continue to work in U-Boot after return from
2988 the Standalone Program.
2989 "OS Kernel Images" are usually images of some Embedded OS which
2990 will take over control completely. Usually these programs
2991 will install their own set of exception handlers, device
2992 drivers, set up the MMU, etc. - this means, that you cannot
2993 expect to re-enter U-Boot except by resetting the CPU.
2994 "RAMDisk Images" are more or less just data blocks, and their
2995 parameters (address, size) are passed to an OS kernel that is
2997 "Multi-File Images" contain several images, typically an OS
2998 (Linux) kernel image and one or more data images like
2999 RAMDisks. This construct is useful for instance when you want
3000 to boot over the network using BOOTP etc., where the boot
3001 server provides just a single image file, but you want to get
3002 for instance an OS kernel and a RAMDisk image.
3004 "Multi-File Images" start with a list of image sizes, each
3005 image size (in bytes) specified by an "uint32_t" in network
3006 byte order. This list is terminated by an "(uint32_t)0".
3007 Immediately after the terminating 0 follow the images, one by
3008 one, all aligned on "uint32_t" boundaries (size rounded up to
3009 a multiple of 4 bytes).
3011 "Firmware Images" are binary images containing firmware (like
3012 U-Boot or FPGA images) which usually will be programmed to
3015 "Script files" are command sequences that will be executed by
3016 U-Boot's command interpreter; this feature is especially
3017 useful when you configure U-Boot to use a real shell (hush)
3018 as command interpreter.
3024 One of the features of U-Boot is that you can dynamically load and
3025 run "standalone" applications, which can use some resources of
3026 U-Boot like console I/O functions or interrupt services.
3028 Two simple examples are included with the sources:
3033 'examples/hello_world.c' contains a small "Hello World" Demo
3034 application; it is automatically compiled when you build U-Boot.
3035 It's configured to run at address 0x00040004, so you can play with it
3039 ## Ready for S-Record download ...
3040 ~>examples/hello_world.srec
3041 1 2 3 4 5 6 7 8 9 10 11 ...
3042 [file transfer complete]
3044 ## Start Addr = 0x00040004
3046 => go 40004 Hello World! This is a test.
3047 ## Starting application at 0x00040004 ...
3058 Hit any key to exit ...
3060 ## Application terminated, rc = 0x0
3062 Another example, which demonstrates how to register a CPM interrupt
3063 handler with the U-Boot code, can be found in 'examples/timer.c'.
3064 Here, a CPM timer is set up to generate an interrupt every second.
3065 The interrupt service routine is trivial, just printing a '.'
3066 character, but this is just a demo program. The application can be
3067 controlled by the following keys:
3069 ? - print current values og the CPM Timer registers
3070 b - enable interrupts and start timer
3071 e - stop timer and disable interrupts
3072 q - quit application
3075 ## Ready for S-Record download ...
3076 ~>examples/timer.srec
3077 1 2 3 4 5 6 7 8 9 10 11 ...
3078 [file transfer complete]
3080 ## Start Addr = 0x00040004
3083 ## Starting application at 0x00040004 ...
3086 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3089 [q, b, e, ?] Set interval 1000000 us
3092 [q, b, e, ?] ........
3093 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3096 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3099 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3102 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3104 [q, b, e, ?] ...Stopping timer
3106 [q, b, e, ?] ## Application terminated, rc = 0x0
3112 Over time, many people have reported problems when trying to use the
3113 "minicom" terminal emulation program for serial download. I (wd)
3114 consider minicom to be broken, and recommend not to use it. Under
3115 Unix, I recommend to use C-Kermit for general purpose use (and
3116 especially for kermit binary protocol download ("loadb" command), and
3117 use "cu" for S-Record download ("loads" command).
3119 Nevertheless, if you absolutely want to use it try adding this
3120 configuration to your "File transfer protocols" section:
3122 Name Program Name U/D FullScr IO-Red. Multi
3123 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3124 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3130 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3131 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3133 Building requires a cross environment; it is known to work on
3134 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3135 need gmake since the Makefiles are not compatible with BSD make).
3136 Note that the cross-powerpc package does not install include files;
3137 attempting to build U-Boot will fail because <machine/ansi.h> is
3138 missing. This file has to be installed and patched manually:
3140 # cd /usr/pkg/cross/powerpc-netbsd/include
3142 # ln -s powerpc machine
3143 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3144 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3146 Native builds *don't* work due to incompatibilities between native
3147 and U-Boot include files.
3149 Booting assumes that (the first part of) the image booted is a
3150 stage-2 loader which in turn loads and then invokes the kernel
3151 proper. Loader sources will eventually appear in the NetBSD source
3152 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3153 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3156 Implementation Internals:
3157 =========================
3159 The following is not intended to be a complete description of every
3160 implementation detail. However, it should help to understand the
3161 inner workings of U-Boot and make it easier to port it to custom
3165 Initial Stack, Global Data:
3166 ---------------------------
3168 The implementation of U-Boot is complicated by the fact that U-Boot
3169 starts running out of ROM (flash memory), usually without access to
3170 system RAM (because the memory controller is not initialized yet).
3171 This means that we don't have writable Data or BSS segments, and BSS
3172 is not initialized as zero. To be able to get a C environment working
3173 at all, we have to allocate at least a minimal stack. Implementation
3174 options for this are defined and restricted by the CPU used: Some CPU
3175 models provide on-chip memory (like the IMMR area on MPC8xx and
3176 MPC826x processors), on others (parts of) the data cache can be
3177 locked as (mis-) used as memory, etc.
3179 Chris Hallinan posted a good summary of these issues to the
3180 u-boot-users mailing list:
3182 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3183 From: "Chris Hallinan" <clh@net1plus.com>
3184 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3187 Correct me if I'm wrong, folks, but the way I understand it
3188 is this: Using DCACHE as initial RAM for Stack, etc, does not
3189 require any physical RAM backing up the cache. The cleverness
3190 is that the cache is being used as a temporary supply of
3191 necessary storage before the SDRAM controller is setup. It's
3192 beyond the scope of this list to expain the details, but you
3193 can see how this works by studying the cache architecture and
3194 operation in the architecture and processor-specific manuals.
3196 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3197 is another option for the system designer to use as an
3198 initial stack/ram area prior to SDRAM being available. Either
3199 option should work for you. Using CS 4 should be fine if your
3200 board designers haven't used it for something that would
3201 cause you grief during the initial boot! It is frequently not
3204 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3205 with your processor/board/system design. The default value
3206 you will find in any recent u-boot distribution in
3207 walnut.h should work for you. I'd set it to a value larger
3208 than your SDRAM module. If you have a 64MB SDRAM module, set
3209 it above 400_0000. Just make sure your board has no resources
3210 that are supposed to respond to that address! That code in
3211 start.S has been around a while and should work as is when
3212 you get the config right.
3217 It is essential to remember this, since it has some impact on the C
3218 code for the initialization procedures:
3220 * Initialized global data (data segment) is read-only. Do not attempt
3223 * Do not use any unitialized global data (or implicitely initialized
3224 as zero data - BSS segment) at all - this is undefined, initiali-
3225 zation is performed later (when relocating to RAM).
3227 * Stack space is very limited. Avoid big data buffers or things like
3230 Having only the stack as writable memory limits means we cannot use
3231 normal global data to share information beween the code. But it
3232 turned out that the implementation of U-Boot can be greatly
3233 simplified by making a global data structure (gd_t) available to all
3234 functions. We could pass a pointer to this data as argument to _all_
3235 functions, but this would bloat the code. Instead we use a feature of
3236 the GCC compiler (Global Register Variables) to share the data: we
3237 place a pointer (gd) to the global data into a register which we
3238 reserve for this purpose.
3240 When choosing a register for such a purpose we are restricted by the
3241 relevant (E)ABI specifications for the current architecture, and by
3242 GCC's implementation.
3244 For PowerPC, the following registers have specific use:
3247 R3-R4: parameter passing and return values
3248 R5-R10: parameter passing
3249 R13: small data area pointer
3253 (U-Boot also uses R14 as internal GOT pointer.)
3255 ==> U-Boot will use R29 to hold a pointer to the global data
3257 Note: on PPC, we could use a static initializer (since the
3258 address of the global data structure is known at compile time),
3259 but it turned out that reserving a register results in somewhat
3260 smaller code - although the code savings are not that big (on
3261 average for all boards 752 bytes for the whole U-Boot image,
3262 624 text + 127 data).
3264 On ARM, the following registers are used:
3266 R0: function argument word/integer result
3267 R1-R3: function argument word
3269 R10: stack limit (used only if stack checking if enabled)
3270 R11: argument (frame) pointer
3271 R12: temporary workspace
3274 R15: program counter
3276 ==> U-Boot will use R8 to hold a pointer to the global data
3282 U-Boot runs in system state and uses physical addresses, i.e. the
3283 MMU is not used either for address mapping nor for memory protection.
3285 The available memory is mapped to fixed addresses using the memory
3286 controller. In this process, a contiguous block is formed for each
3287 memory type (Flash, SDRAM, SRAM), even when it consists of several
3288 physical memory banks.
3290 U-Boot is installed in the first 128 kB of the first Flash bank (on
3291 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3292 booting and sizing and initializing DRAM, the code relocates itself
3293 to the upper end of DRAM. Immediately below the U-Boot code some
3294 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3295 configuration setting]. Below that, a structure with global Board
3296 Info data is placed, followed by the stack (growing downward).
3298 Additionally, some exception handler code is copied to the low 8 kB
3299 of DRAM (0x00000000 ... 0x00001FFF).
3301 So a typical memory configuration with 16 MB of DRAM could look like
3304 0x0000 0000 Exception Vector code
3307 0x0000 2000 Free for Application Use
3313 0x00FB FF20 Monitor Stack (Growing downward)
3314 0x00FB FFAC Board Info Data and permanent copy of global data
3315 0x00FC 0000 Malloc Arena
3318 0x00FE 0000 RAM Copy of Monitor Code
3319 ... eventually: LCD or video framebuffer
3320 ... eventually: pRAM (Protected RAM - unchanged by reset)
3321 0x00FF FFFF [End of RAM]
3324 System Initialization:
3325 ----------------------
3327 In the reset configuration, U-Boot starts at the reset entry point
3328 (on most PowerPC systens at address 0x00000100). Because of the reset
3329 configuration for CS0# this is a mirror of the onboard Flash memory.
3330 To be able to re-map memory U-Boot then jumps to its link address.
3331 To be able to implement the initialization code in C, a (small!)
3332 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3333 which provide such a feature like MPC8xx or MPC8260), or in a locked
3334 part of the data cache. After that, U-Boot initializes the CPU core,
3335 the caches and the SIU.
3337 Next, all (potentially) available memory banks are mapped using a
3338 preliminary mapping. For example, we put them on 512 MB boundaries
3339 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3340 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3341 programmed for SDRAM access. Using the temporary configuration, a
3342 simple memory test is run that determines the size of the SDRAM
3345 When there is more than one SDRAM bank, and the banks are of
3346 different size, the largest is mapped first. For equal size, the first
3347 bank (CS2#) is mapped first. The first mapping is always for address
3348 0x00000000, with any additional banks following immediately to create
3349 contiguous memory starting from 0.
3351 Then, the monitor installs itself at the upper end of the SDRAM area
3352 and allocates memory for use by malloc() and for the global Board
3353 Info data; also, the exception vector code is copied to the low RAM
3354 pages, and the final stack is set up.
3356 Only after this relocation will you have a "normal" C environment;
3357 until that you are restricted in several ways, mostly because you are
3358 running from ROM, and because the code will have to be relocated to a
3362 U-Boot Porting Guide:
3363 ----------------------
3365 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3369 int main (int argc, char *argv[])
3371 sighandler_t no_more_time;
3373 signal (SIGALRM, no_more_time);
3374 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3376 if (available_money > available_manpower) {
3377 pay consultant to port U-Boot;
3381 Download latest U-Boot source;
3383 Subscribe to u-boot-users mailing list;
3386 email ("Hi, I am new to U-Boot, how do I get started?");
3390 Read the README file in the top level directory;
3391 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3392 Read the source, Luke;
3395 if (available_money > toLocalCurrency ($2500)) {
3398 Add a lot of aggravation and time;
3401 Create your own board support subdirectory;
3403 Create your own board config file;
3407 Add / modify source code;
3411 email ("Hi, I am having problems...");
3413 Send patch file to Wolfgang;
3418 void no_more_time (int sig)
3427 All contributions to U-Boot should conform to the Linux kernel
3428 coding style; see the file "Documentation/CodingStyle" in your Linux
3429 kernel source directory.
3431 Please note that U-Boot is implemented in C (and to some small parts
3432 in Assembler); no C++ is used, so please do not use C++ style
3433 comments (//) in your code.
3435 Please also stick to the following formatting rules:
3436 - remove any trailing white space
3437 - use TAB characters for indentation, not spaces
3438 - make sure NOT to use DOS '\r\n' line feeds
3439 - do not add more than 2 empty lines to source files
3440 - do not add trailing empty lines to source files
3442 Submissions which do not conform to the standards may be returned
3443 with a request to reformat the changes.
3449 Since the number of patches for U-Boot is growing, we need to
3450 establish some rules. Submissions which do not conform to these rules
3451 may be rejected, even when they contain important and valuable stuff.
3453 Patches shall be sent to the u-boot-users mailing list.
3455 When you send a patch, please include the following information with
3458 * For bug fixes: a description of the bug and how your patch fixes
3459 this bug. Please try to include a way of demonstrating that the
3460 patch actually fixes something.
3462 * For new features: a description of the feature and your
3465 * A CHANGELOG entry as plaintext (separate from the patch)
3467 * For major contributions, your entry to the CREDITS file
3469 * When you add support for a new board, don't forget to add this
3470 board to the MAKEALL script, too.
3472 * If your patch adds new configuration options, don't forget to
3473 document these in the README file.
3475 * The patch itself. If you are accessing the CVS repository use "cvs
3476 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3477 version of diff does not support these options, then get the latest
3478 version of GNU diff.
3480 The current directory when running this command shall be the top
3481 level directory of the U-Boot source tree, or it's parent directory
3482 (i. e. please make sure that your patch includes sufficient
3483 directory information for the affected files).
3485 We accept patches as plain text, MIME attachments or as uuencoded
3488 * If one logical set of modifications affects or creates several
3489 files, all these changes shall be submitted in a SINGLE patch file.
3491 * Changesets that contain different, unrelated modifications shall be
3492 submitted as SEPARATE patches, one patch per changeset.
3497 * Before sending the patch, run the MAKEALL script on your patched
3498 source tree and make sure that no errors or warnings are reported
3499 for any of the boards.
3501 * Keep your modifications to the necessary minimum: A patch
3502 containing several unrelated changes or arbitrary reformats will be
3503 returned with a request to re-formatting / split it.
3505 * If you modify existing code, make sure that your new code does not
3506 add to the memory footprint of the code ;-) Small is beautiful!
3507 When adding new features, these should compile conditionally only
3508 (using #ifdef), and the resulting code with the new feature
3509 disabled must not need more memory than the old code without your
3512 * Remember that there is a size limit of 40 kB per message on the
3513 u-boot-users mailing list. Compression may help.
projects / platform / kernel / u-boot.git / blob