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_PCI405
265 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC2
266 CONFIG_AMX860 CONFIG_GTH CONFIG_PCIPPC6
267 CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e
268 CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405
269 CONFIG_c2mon CONFIG_hymod CONFIG_PM826
270 CONFIG_CANBT CONFIG_IAD210 CONFIG_ppmc8260
271 CONFIG_CCM CONFIG_ICU862 CONFIG_QS823
272 CONFIG_CMI CONFIG_IP860 CONFIG_QS850
273 CONFIG_cogent_mpc8260 CONFIG_IPHASE4539 CONFIG_QS860T
274 CONFIG_cogent_mpc8xx CONFIG_IVML24 CONFIG_RBC823
275 CONFIG_CPCI405 CONFIG_IVML24_128 CONFIG_RPXClassic
276 CONFIG_CPCI4052 CONFIG_IVML24_256 CONFIG_RPXlite
277 CONFIG_CPCIISER4 CONFIG_IVMS8 CONFIG_RPXsuper
278 CONFIG_CPU86 CONFIG_IVMS8_128 CONFIG_rsdproto
279 CONFIG_CRAYL1 CONFIG_IVMS8_256 CONFIG_sacsng
280 CONFIG_CSB272 CONFIG_JSE CONFIG_Sandpoint8240
281 CONFIG_CU824 CONFIG_LANTEC CONFIG_Sandpoint8245
282 CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8260
283 CONFIG_DB64360 CONFIG_MBX CONFIG_sbc8560
284 CONFIG_DB64460 CONFIG_MBX860T CONFIG_SM850
285 CONFIG_DU405 CONFIG_MHPC CONFIG_SPD823TS
286 CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_STXGP3
287 CONFIG_EBONY CONFIG_MOUSSE CONFIG_SXNI855T
288 CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM823L
289 CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM8260
290 CONFIG_ep8260 CONFIG_MPC8540EVAL CONFIG_TQM850L
291 CONFIG_ERIC CONFIG_MPC8560ADS CONFIG_TQM855L
292 CONFIG_ESTEEM192E CONFIG_MUSENKI CONFIG_TQM860L
293 CONFIG_ETX094 CONFIG_MVS1 CONFIG_TTTech
294 CONFIG_EVB64260 CONFIG_NETPHONE CONFIG_UTX8245
295 CONFIG_FADS823 CONFIG_NETTA CONFIG_V37
296 CONFIG_FADS850SAR CONFIG_NETVIA CONFIG_W7OLMC
297 CONFIG_FADS860T CONFIG_NX823 CONFIG_W7OLMG
298 CONFIG_FLAGADM CONFIG_OCRTC CONFIG_WALNUT
299 CONFIG_FPS850L CONFIG_ORSG CONFIG_ZPC1900
300 CONFIG_FPS860L CONFIG_OXC CONFIG_ZUMA
305 CONFIG_ARMADILLO, CONFIG_AT91RM9200DK, CONFIG_CERF250,
306 CONFIG_DNP1110, CONFIG_EP7312, CONFIG_H2_OMAP1610,
307 CONFIG_HHP_CRADLE, CONFIG_IMPA7, CONFIG_INNOVATOROMAP1510,
308 CONFIG_INNOVATOROMAP1610, CONFIG_KB9202, CONFIG_LART,
309 CONFIG_LPD7A400, CONFIG_LUBBOCK, CONFIG_OSK_OMAP5912,
310 CONFIG_OMAP2420H4, CONFIG_SHANNON, CONFIG_P2_OMAP730,
311 CONFIG_SMDK2400, CONFIG_SMDK2410, CONFIG_TRAB,
314 MicroBlaze based boards:
315 ------------------------
320 ------------------------
322 CONFIG_PCI5441 CONFIG_PK1C20
325 - CPU Module Type: (if CONFIG_COGENT is defined)
326 Define exactly one of
328 --- FIXME --- not tested yet:
329 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
330 CONFIG_CMA287_23, CONFIG_CMA287_50
332 - Motherboard Type: (if CONFIG_COGENT is defined)
333 Define exactly one of
334 CONFIG_CMA101, CONFIG_CMA102
336 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
337 Define one or more of
340 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
341 Define one or more of
342 CONFIG_LCD_HEARTBEAT - update a character position on
343 the lcd display every second with
346 - Board flavour: (if CONFIG_MPC8260ADS is defined)
349 CFG_8260ADS - original MPC8260ADS
350 CFG_8266ADS - MPC8266ADS
351 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
352 CFG_8272ADS - MPC8272ADS
354 - MPC824X Family Member (if CONFIG_MPC824X is defined)
355 Define exactly one of
356 CONFIG_MPC8240, CONFIG_MPC8245
358 - 8xx CPU Options: (if using an MPC8xx cpu)
359 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
360 get_gclk_freq() cannot work
361 e.g. if there is no 32KHz
362 reference PIT/RTC clock
363 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
366 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
369 CONFIG_8xx_CPUCLK_DEFAULT
370 See doc/README.MPC866
374 Define this to measure the actual CPU clock instead
375 of relying on the correctness of the configured
376 values. Mostly useful for board bringup to make sure
377 the PLL is locked at the intended frequency. Note
378 that this requires a (stable) reference clock (32 kHz
379 RTC clock or CFG_8XX_XIN)
381 - Linux Kernel Interface:
384 U-Boot stores all clock information in Hz
385 internally. For binary compatibility with older Linux
386 kernels (which expect the clocks passed in the
387 bd_info data to be in MHz) the environment variable
388 "clocks_in_mhz" can be defined so that U-Boot
389 converts clock data to MHZ before passing it to the
391 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
392 "clocks_in_mhz=1" is automatically included in the
395 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
397 When transfering memsize parameter to linux, some versions
398 expect it to be in bytes, others in MB.
399 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
404 Define this if you want support for Amba PrimeCell PL010 UARTs.
408 Define this if you want support for Amba PrimeCell PL011 UARTs.
412 If you have Amba PrimeCell PL011 UARTs, set this variable to
413 the clock speed of the UARTs.
417 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
418 define this to a list of base addresses for each (supported)
419 port. See e.g. include/configs/versatile.h
423 Depending on board, define exactly one serial port
424 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
425 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
426 console by defining CONFIG_8xx_CONS_NONE
428 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
429 port routines must be defined elsewhere
430 (i.e. serial_init(), serial_getc(), ...)
433 Enables console device for a color framebuffer. Needs following
434 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
435 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
437 VIDEO_HW_RECTFILL graphic chip supports
440 VIDEO_HW_BITBLT graphic chip supports
441 bit-blit (cf. smiLynxEM)
442 VIDEO_VISIBLE_COLS visible pixel columns
444 VIDEO_VISIBLE_ROWS visible pixel rows
445 VIDEO_PIXEL_SIZE bytes per pixel
446 VIDEO_DATA_FORMAT graphic data format
447 (0-5, cf. cfb_console.c)
448 VIDEO_FB_ADRS framebuffer address
449 VIDEO_KBD_INIT_FCT keyboard int fct
450 (i.e. i8042_kbd_init())
451 VIDEO_TSTC_FCT test char fct
453 VIDEO_GETC_FCT get char fct
455 CONFIG_CONSOLE_CURSOR cursor drawing on/off
456 (requires blink timer
458 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
459 CONFIG_CONSOLE_TIME display time/date info in
461 (requires CFG_CMD_DATE)
462 CONFIG_VIDEO_LOGO display Linux logo in
464 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
465 linux_logo.h for logo.
466 Requires CONFIG_VIDEO_LOGO
467 CONFIG_CONSOLE_EXTRA_INFO
468 addional board info beside
471 When CONFIG_CFB_CONSOLE is defined, video console is
472 default i/o. Serial console can be forced with
473 environment 'console=serial'.
475 When CONFIG_SILENT_CONSOLE is defined, all console
476 messages (by U-Boot and Linux!) can be silenced with
477 the "silent" environment variable. See
478 doc/README.silent for more information.
481 CONFIG_BAUDRATE - in bps
482 Select one of the baudrates listed in
483 CFG_BAUDRATE_TABLE, see below.
484 CFG_BRGCLK_PRESCALE, baudrate prescale
486 - Interrupt driven serial port input:
487 CONFIG_SERIAL_SOFTWARE_FIFO
490 Use an interrupt handler for receiving data on the
491 serial port. It also enables using hardware handshake
492 (RTS/CTS) and UART's built-in FIFO. Set the number of
493 bytes the interrupt driven input buffer should have.
495 Leave undefined to disable this feature, including
496 disable the buffer and hardware handshake.
498 - Console UART Number:
502 If defined internal UART1 (and not UART0) is used
503 as default U-Boot console.
505 - Boot Delay: CONFIG_BOOTDELAY - in seconds
506 Delay before automatically booting the default image;
507 set to -1 to disable autoboot.
509 See doc/README.autoboot for these options that
510 work with CONFIG_BOOTDELAY. None are required.
511 CONFIG_BOOT_RETRY_TIME
512 CONFIG_BOOT_RETRY_MIN
513 CONFIG_AUTOBOOT_KEYED
514 CONFIG_AUTOBOOT_PROMPT
515 CONFIG_AUTOBOOT_DELAY_STR
516 CONFIG_AUTOBOOT_STOP_STR
517 CONFIG_AUTOBOOT_DELAY_STR2
518 CONFIG_AUTOBOOT_STOP_STR2
519 CONFIG_ZERO_BOOTDELAY_CHECK
520 CONFIG_RESET_TO_RETRY
524 Only needed when CONFIG_BOOTDELAY is enabled;
525 define a command string that is automatically executed
526 when no character is read on the console interface
527 within "Boot Delay" after reset.
530 This can be used to pass arguments to the bootm
531 command. The value of CONFIG_BOOTARGS goes into the
532 environment value "bootargs".
534 CONFIG_RAMBOOT and CONFIG_NFSBOOT
535 The value of these goes into the environment as
536 "ramboot" and "nfsboot" respectively, and can be used
537 as a convenience, when switching between booting from
543 When this option is #defined, the existence of the
544 environment variable "preboot" will be checked
545 immediately before starting the CONFIG_BOOTDELAY
546 countdown and/or running the auto-boot command resp.
547 entering interactive mode.
549 This feature is especially useful when "preboot" is
550 automatically generated or modified. For an example
551 see the LWMON board specific code: here "preboot" is
552 modified when the user holds down a certain
553 combination of keys on the (special) keyboard when
556 - Serial Download Echo Mode:
558 If defined to 1, all characters received during a
559 serial download (using the "loads" command) are
560 echoed back. This might be needed by some terminal
561 emulations (like "cu"), but may as well just take
562 time on others. This setting #define's the initial
563 value of the "loads_echo" environment variable.
565 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
567 Select one of the baudrates listed in
568 CFG_BAUDRATE_TABLE, see below.
572 Most monitor functions can be selected (or
573 de-selected) by adjusting the definition of
574 CONFIG_COMMANDS; to select individual functions,
575 #define CONFIG_COMMANDS by "OR"ing any of the
578 #define enables commands:
579 -------------------------
580 CFG_CMD_ASKENV * ask for env variable
581 CFG_CMD_AUTOSCRIPT Autoscript Support
583 CFG_CMD_BEDBUG * Include BedBug Debugger
584 CFG_CMD_BMP * BMP support
585 CFG_CMD_BSP * Board specific commands
587 CFG_CMD_CACHE * icache, dcache
588 CFG_CMD_CONSOLE coninfo
589 CFG_CMD_DATE * support for RTC, date/time...
590 CFG_CMD_DHCP * DHCP support
591 CFG_CMD_DIAG * Diagnostics
592 CFG_CMD_DOC * Disk-On-Chip Support
593 CFG_CMD_DTT * Digital Therm and Thermostat
594 CFG_CMD_ECHO * echo arguments
595 CFG_CMD_EEPROM * EEPROM read/write support
596 CFG_CMD_ELF * bootelf, bootvx
598 CFG_CMD_FDC * Floppy Disk Support
599 CFG_CMD_FAT * FAT partition support
600 CFG_CMD_FDOS * Dos diskette Support
601 CFG_CMD_FLASH flinfo, erase, protect
602 CFG_CMD_FPGA FPGA device initialization support
603 CFG_CMD_HWFLOW * RTS/CTS hw flow control
604 CFG_CMD_I2C * I2C serial bus support
605 CFG_CMD_IDE * IDE harddisk support
607 CFG_CMD_IMLS List all found images
608 CFG_CMD_IMMAP * IMMR dump support
609 CFG_CMD_IRQ * irqinfo
610 CFG_CMD_ITEST Integer/string test of 2 values
611 CFG_CMD_JFFS2 * JFFS2 Support
615 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
617 CFG_CMD_MISC Misc functions like sleep etc
618 CFG_CMD_MMC * MMC memory mapped support
619 CFG_CMD_MII * MII utility commands
620 CFG_CMD_NAND * NAND support
621 CFG_CMD_NET bootp, tftpboot, rarpboot
622 CFG_CMD_PCI * pciinfo
623 CFG_CMD_PCMCIA * PCMCIA support
624 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
625 CFG_CMD_PORTIO * Port I/O
626 CFG_CMD_REGINFO * Register dump
627 CFG_CMD_RUN run command in env variable
628 CFG_CMD_SAVES * save S record dump
629 CFG_CMD_SCSI * SCSI Support
630 CFG_CMD_SDRAM * print SDRAM configuration information
631 (requires CFG_CMD_I2C)
632 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
633 CFG_CMD_SPI * SPI serial bus support
634 CFG_CMD_USB * USB support
635 CFG_CMD_VFD * VFD support (TRAB)
636 CFG_CMD_BSP * Board SPecific functions
637 CFG_CMD_CDP * Cisco Discover Protocol support
638 -----------------------------------------------
641 CONFIG_CMD_DFL Default configuration; at the moment
642 this is includes all commands, except
643 the ones marked with "*" in the list
646 If you don't define CONFIG_COMMANDS it defaults to
647 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
648 override the default settings in the respective
651 EXAMPLE: If you want all functions except of network
652 support you can write:
654 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
657 Note: Don't enable the "icache" and "dcache" commands
658 (configuration option CFG_CMD_CACHE) unless you know
659 what you (and your U-Boot users) are doing. Data
660 cache cannot be enabled on systems like the 8xx or
661 8260 (where accesses to the IMMR region must be
662 uncached), and it cannot be disabled on all other
663 systems where we (mis-) use the data cache to hold an
664 initial stack and some data.
667 XXX - this list needs to get updated!
671 If this variable is defined, it enables watchdog
672 support. There must be support in the platform specific
673 code for a watchdog. For the 8xx and 8260 CPUs, the
674 SIU Watchdog feature is enabled in the SYPCR
678 CONFIG_VERSION_VARIABLE
679 If this variable is defined, an environment variable
680 named "ver" is created by U-Boot showing the U-Boot
681 version as printed by the "version" command.
682 This variable is readonly.
686 When CFG_CMD_DATE is selected, the type of the RTC
687 has to be selected, too. Define exactly one of the
690 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
691 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
692 CONFIG_RTC_MC146818 - use MC146818 RTC
693 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
694 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
695 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
696 CONFIG_RTC_DS164x - use Dallas DS164x RTC
697 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
699 Note that if the RTC uses I2C, then the I2C interface
700 must also be configured. See I2C Support, below.
704 When CONFIG_TIMESTAMP is selected, the timestamp
705 (date and time) of an image is printed by image
706 commands like bootm or iminfo. This option is
707 automatically enabled when you select CFG_CMD_DATE .
710 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
711 and/or CONFIG_ISO_PARTITION
713 If IDE or SCSI support is enabled (CFG_CMD_IDE or
714 CFG_CMD_SCSI) you must configure support for at least
715 one partition type as well.
718 CONFIG_IDE_RESET_ROUTINE - this is defined in several
719 board configurations files but used nowhere!
721 CONFIG_IDE_RESET - is this is defined, IDE Reset will
722 be performed by calling the function
723 ide_set_reset(int reset)
724 which has to be defined in a board specific file
729 Set this to enable ATAPI support.
734 Set this to enable support for disks larger than 137GB
735 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
736 Whithout these , LBA48 support uses 32bit variables and will 'only'
737 support disks up to 2.1TB.
740 When enabled, makes the IDE subsystem use 64bit sector addresses.
744 At the moment only there is only support for the
745 SYM53C8XX SCSI controller; define
746 CONFIG_SCSI_SYM53C8XX to enable it.
748 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
749 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
750 CFG_SCSI_MAX_LUN] can be adjusted to define the
751 maximum numbers of LUNs, SCSI ID's and target
753 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
755 - NETWORK Support (PCI):
757 Support for Intel 8254x gigabit chips.
760 Support for Intel 82557/82559/82559ER chips.
761 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
762 write routine for first time initialisation.
765 Support for Digital 2114x chips.
766 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
767 modem chip initialisation (KS8761/QS6611).
770 Support for National dp83815 chips.
773 Support for National dp8382[01] gigabit chips.
775 - NETWORK Support (other):
777 CONFIG_DRIVER_LAN91C96
778 Support for SMSC's LAN91C96 chips.
781 Define this to hold the physical address
782 of the LAN91C96's I/O space
784 CONFIG_LAN91C96_USE_32_BIT
785 Define this to enable 32 bit addressing
787 CONFIG_DRIVER_SMC91111
788 Support for SMSC's LAN91C111 chip
791 Define this to hold the physical address
792 of the device (I/O space)
794 CONFIG_SMC_USE_32_BIT
795 Define this if data bus is 32 bits
797 CONFIG_SMC_USE_IOFUNCS
798 Define this to use i/o functions instead of macros
799 (some hardware wont work with macros)
802 At the moment only the UHCI host controller is
803 supported (PIP405, MIP405, MPC5200); define
804 CONFIG_USB_UHCI to enable it.
805 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
806 and define CONFIG_USB_STORAGE to enable the USB
809 Supported are USB Keyboards and USB Floppy drives
811 MPC5200 USB requires additional defines:
813 for 528 MHz Clock: 0x0001bbbb
815 for differential drivers: 0x00001000
816 for single ended drivers: 0x00005000
820 The MMC controller on the Intel PXA is supported. To
821 enable this define CONFIG_MMC. The MMC can be
822 accessed from the boot prompt by mapping the device
823 to physical memory similar to flash. Command line is
824 enabled with CFG_CMD_MMC. The MMC driver also works with
825 the FAT fs. This is enabled with CFG_CMD_FAT.
827 - Journaling Flash filesystem support:
828 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
829 CONFIG_JFFS2_NAND_DEV
830 Define these for a default partition on a NAND device
832 CFG_JFFS2_FIRST_SECTOR,
833 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
834 Define these for a default partition on a NOR device
837 Define this to create an own partition. You have to provide a
838 function struct part_info* jffs2_part_info(int part_num)
840 If you define only one JFFS2 partition you may also want to
841 #define CFG_JFFS_SINGLE_PART 1
842 to disable the command chpart. This is the default when you
843 have not defined a custom partition
848 Define this to enable standard (PC-Style) keyboard
852 Standard PC keyboard driver with US (is default) and
853 GERMAN key layout (switch via environment 'keymap=de') support.
854 Export function i8042_kbd_init, i8042_tstc and i8042_getc
855 for cfb_console. Supports cursor blinking.
860 Define this to enable video support (for output to
865 Enable Chips & Technologies 69000 Video chip
867 CONFIG_VIDEO_SMI_LYNXEM
868 Enable Silicon Motion SMI 712/710/810 Video chip. The
869 video output is selected via environment 'videoout'
870 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
873 For the CT69000 and SMI_LYNXEM drivers, videomode is
874 selected via environment 'videomode'. Two diferent ways
876 - "videomode=num" 'num' is a standard LiLo mode numbers.
877 Following standard modes are supported (* is default):
879 Colors 640x480 800x600 1024x768 1152x864 1280x1024
880 -------------+---------------------------------------------
881 8 bits | 0x301* 0x303 0x305 0x161 0x307
882 15 bits | 0x310 0x313 0x316 0x162 0x319
883 16 bits | 0x311 0x314 0x317 0x163 0x31A
884 24 bits | 0x312 0x315 0x318 ? 0x31B
885 -------------+---------------------------------------------
886 (i.e. setenv videomode 317; saveenv; reset;)
888 - "videomode=bootargs" all the video parameters are parsed
889 from the bootargs. (See drivers/videomodes.c)
892 CONFIG_VIDEO_SED13806
893 Enable Epson SED13806 driver. This driver supports 8bpp
894 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
895 or CONFIG_VIDEO_SED13806_16BPP
900 Define this to enable a custom keyboard support.
901 This simply calls drv_keyboard_init() which must be
902 defined in your board-specific files.
903 The only board using this so far is RBC823.
905 - LCD Support: CONFIG_LCD
907 Define this to enable LCD support (for output to LCD
908 display); also select one of the supported displays
909 by defining one of these:
911 CONFIG_NEC_NL6448AC33:
913 NEC NL6448AC33-18. Active, color, single scan.
915 CONFIG_NEC_NL6448BC20
917 NEC NL6448BC20-08. 6.5", 640x480.
918 Active, color, single scan.
920 CONFIG_NEC_NL6448BC33_54
922 NEC NL6448BC33-54. 10.4", 640x480.
923 Active, color, single scan.
927 Sharp 320x240. Active, color, single scan.
928 It isn't 16x9, and I am not sure what it is.
930 CONFIG_SHARP_LQ64D341
932 Sharp LQ64D341 display, 640x480.
933 Active, color, single scan.
937 HLD1045 display, 640x480.
938 Active, color, single scan.
942 Optrex CBL50840-2 NF-FW 99 22 M5
944 Hitachi LMG6912RPFC-00T
948 320x240. Black & white.
950 Normally display is black on white background; define
951 CFG_WHITE_ON_BLACK to get it inverted.
953 - Splash Screen Support: CONFIG_SPLASH_SCREEN
955 If this option is set, the environment is checked for
956 a variable "splashimage". If found, the usual display
957 of logo, copyright and system information on the LCD
958 is suppressed and the BMP image at the address
959 specified in "splashimage" is loaded instead. The
960 console is redirected to the "nulldev", too. This
961 allows for a "silent" boot where a splash screen is
962 loaded very quickly after power-on.
964 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
966 If this option is set, additionally to standard BMP
967 images, gzipped BMP images can be displayed via the
968 splashscreen support or the bmp command.
970 - Compression support:
973 If this option is set, support for bzip2 compressed
974 images is included. If not, only uncompressed and gzip
975 compressed images are supported.
977 NOTE: the bzip2 algorithm requires a lot of RAM, so
978 the malloc area (as defined by CFG_MALLOC_LEN) should
984 The address of PHY on MII bus.
986 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
988 The clock frequency of the MII bus
992 If this option is set, support for speed/duplex
993 detection of Gigabit PHY is included.
995 CONFIG_PHY_RESET_DELAY
997 Some PHY like Intel LXT971A need extra delay after
998 reset before any MII register access is possible.
999 For such PHY, set this option to the usec delay
1000 required. (minimum 300usec for LXT971A)
1002 CONFIG_PHY_CMD_DELAY (ppc4xx)
1004 Some PHY like Intel LXT971A need extra delay after
1005 command issued before MII status register can be read
1012 Define a default value for ethernet address to use
1013 for the respective ethernet interface, in case this
1014 is not determined automatically.
1019 Define a default value for the IP address to use for
1020 the default ethernet interface, in case this is not
1021 determined through e.g. bootp.
1023 - Server IP address:
1026 Defines a default value for theIP address of a TFTP
1027 server to contact when using the "tftboot" command.
1029 - BOOTP Recovery Mode:
1030 CONFIG_BOOTP_RANDOM_DELAY
1032 If you have many targets in a network that try to
1033 boot using BOOTP, you may want to avoid that all
1034 systems send out BOOTP requests at precisely the same
1035 moment (which would happen for instance at recovery
1036 from a power failure, when all systems will try to
1037 boot, thus flooding the BOOTP server. Defining
1038 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1039 inserted before sending out BOOTP requests. The
1040 following delays are insterted then:
1042 1st BOOTP request: delay 0 ... 1 sec
1043 2nd BOOTP request: delay 0 ... 2 sec
1044 3rd BOOTP request: delay 0 ... 4 sec
1046 BOOTP requests: delay 0 ... 8 sec
1048 - DHCP Advanced Options:
1051 You can fine tune the DHCP functionality by adding
1052 these flags to the CONFIG_BOOTP_MASK define:
1054 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1055 serverip from a DHCP server, it is possible that more
1056 than one DNS serverip is offered to the client.
1057 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1058 serverip will be stored in the additional environment
1059 variable "dnsip2". The first DNS serverip is always
1060 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1061 is added to the CONFIG_BOOTP_MASK.
1063 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1064 to do a dynamic update of a DNS server. To do this, they
1065 need the hostname of the DHCP requester.
1066 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1067 CONFIG_BOOTP_MASK, the content of the "hostname"
1068 environment variable is passed as option 12 to
1072 CONFIG_CDP_DEVICE_ID
1074 The device id used in CDP trigger frames.
1076 CONFIG_CDP_DEVICE_ID_PREFIX
1078 A two character string which is prefixed to the MAC address
1083 A printf format string which contains the ascii name of
1084 the port. Normally is set to "eth%d" which sets
1085 eth0 for the first ethernet, eth1 for the second etc.
1087 CONFIG_CDP_CAPABILITIES
1089 A 32bit integer which indicates the device capabilities;
1090 0x00000010 for a normal host which does not forwards.
1094 An ascii string containing the version of the software.
1098 An ascii string containing the name of the platform.
1102 A 32bit integer sent on the trigger.
1104 CONFIG_CDP_POWER_CONSUMPTION
1106 A 16bit integer containing the power consumption of the
1107 device in .1 of milliwatts.
1109 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1111 A byte containing the id of the VLAN.
1113 - Status LED: CONFIG_STATUS_LED
1115 Several configurations allow to display the current
1116 status using a LED. For instance, the LED will blink
1117 fast while running U-Boot code, stop blinking as
1118 soon as a reply to a BOOTP request was received, and
1119 start blinking slow once the Linux kernel is running
1120 (supported by a status LED driver in the Linux
1121 kernel). Defining CONFIG_STATUS_LED enables this
1124 - CAN Support: CONFIG_CAN_DRIVER
1126 Defining CONFIG_CAN_DRIVER enables CAN driver support
1127 on those systems that support this (optional)
1128 feature, like the TQM8xxL modules.
1130 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1132 These enable I2C serial bus commands. Defining either of
1133 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1134 include the appropriate I2C driver for the selected cpu.
1136 This will allow you to use i2c commands at the u-boot
1137 command line (as long as you set CFG_CMD_I2C in
1138 CONFIG_COMMANDS) and communicate with i2c based realtime
1139 clock chips. See common/cmd_i2c.c for a description of the
1140 command line interface.
1142 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1144 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1145 bit-banging) driver instead of CPM or similar hardware
1148 There are several other quantities that must also be
1149 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1151 In both cases you will need to define CFG_I2C_SPEED
1152 to be the frequency (in Hz) at which you wish your i2c bus
1153 to run and CFG_I2C_SLAVE to be the address of this node (ie
1154 the cpu's i2c node address).
1156 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1157 sets the cpu up as a master node and so its address should
1158 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1159 p.16-473). So, set CFG_I2C_SLAVE to 0.
1161 That's all that's required for CONFIG_HARD_I2C.
1163 If you use the software i2c interface (CONFIG_SOFT_I2C)
1164 then the following macros need to be defined (examples are
1165 from include/configs/lwmon.h):
1169 (Optional). Any commands necessary to enable the I2C
1170 controller or configure ports.
1172 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1176 (Only for MPC8260 CPU). The I/O port to use (the code
1177 assumes both bits are on the same port). Valid values
1178 are 0..3 for ports A..D.
1182 The code necessary to make the I2C data line active
1183 (driven). If the data line is open collector, this
1186 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1190 The code necessary to make the I2C data line tri-stated
1191 (inactive). If the data line is open collector, this
1194 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1198 Code that returns TRUE if the I2C data line is high,
1201 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1205 If <bit> is TRUE, sets the I2C data line high. If it
1206 is FALSE, it clears it (low).
1208 eg: #define I2C_SDA(bit) \
1209 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1210 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1214 If <bit> is TRUE, sets the I2C clock line high. If it
1215 is FALSE, it clears it (low).
1217 eg: #define I2C_SCL(bit) \
1218 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1219 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1223 This delay is invoked four times per clock cycle so this
1224 controls the rate of data transfer. The data rate thus
1225 is 1 / (I2C_DELAY * 4). Often defined to be something
1228 #define I2C_DELAY udelay(2)
1232 When a board is reset during an i2c bus transfer
1233 chips might think that the current transfer is still
1234 in progress. On some boards it is possible to access
1235 the i2c SCLK line directly, either by using the
1236 processor pin as a GPIO or by having a second pin
1237 connected to the bus. If this option is defined a
1238 custom i2c_init_board() routine in boards/xxx/board.c
1239 is run early in the boot sequence.
1241 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1243 This option enables configuration of bi_iic_fast[] flags
1244 in u-boot bd_info structure based on u-boot environment
1245 variable "i2cfast". (see also i2cfast)
1247 - SPI Support: CONFIG_SPI
1249 Enables SPI driver (so far only tested with
1250 SPI EEPROM, also an instance works with Crystal A/D and
1251 D/As on the SACSng board)
1255 Enables extended (16-bit) SPI EEPROM addressing.
1256 (symmetrical to CONFIG_I2C_X)
1260 Enables a software (bit-bang) SPI driver rather than
1261 using hardware support. This is a general purpose
1262 driver that only requires three general I/O port pins
1263 (two outputs, one input) to function. If this is
1264 defined, the board configuration must define several
1265 SPI configuration items (port pins to use, etc). For
1266 an example, see include/configs/sacsng.h.
1268 - FPGA Support: CONFIG_FPGA_COUNT
1270 Specify the number of FPGA devices to support.
1274 Used to specify the types of FPGA devices. For example,
1275 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1277 CFG_FPGA_PROG_FEEDBACK
1279 Enable printing of hash marks during FPGA configuration.
1283 Enable checks on FPGA configuration interface busy
1284 status by the configuration function. This option
1285 will require a board or device specific function to
1290 If defined, a function that provides delays in the FPGA
1291 configuration driver.
1293 CFG_FPGA_CHECK_CTRLC
1294 Allow Control-C to interrupt FPGA configuration
1296 CFG_FPGA_CHECK_ERROR
1298 Check for configuration errors during FPGA bitfile
1299 loading. For example, abort during Virtex II
1300 configuration if the INIT_B line goes low (which
1301 indicated a CRC error).
1305 Maximum time to wait for the INIT_B line to deassert
1306 after PROB_B has been deasserted during a Virtex II
1307 FPGA configuration sequence. The default time is 500
1312 Maximum time to wait for BUSY to deassert during
1313 Virtex II FPGA configuration. The default is 5 mS.
1315 CFG_FPGA_WAIT_CONFIG
1317 Time to wait after FPGA configuration. The default is
1320 - Configuration Management:
1323 If defined, this string will be added to the U-Boot
1324 version information (U_BOOT_VERSION)
1326 - Vendor Parameter Protection:
1328 U-Boot considers the values of the environment
1329 variables "serial#" (Board Serial Number) and
1330 "ethaddr" (Ethernet Address) to be parameters that
1331 are set once by the board vendor / manufacturer, and
1332 protects these variables from casual modification by
1333 the user. Once set, these variables are read-only,
1334 and write or delete attempts are rejected. You can
1335 change this behviour:
1337 If CONFIG_ENV_OVERWRITE is #defined in your config
1338 file, the write protection for vendor parameters is
1339 completely disabled. Anybody can change or delete
1342 Alternatively, if you #define _both_ CONFIG_ETHADDR
1343 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1344 ethernet address is installed in the environment,
1345 which can be changed exactly ONCE by the user. [The
1346 serial# is unaffected by this, i. e. it remains
1352 Define this variable to enable the reservation of
1353 "protected RAM", i. e. RAM which is not overwritten
1354 by U-Boot. Define CONFIG_PRAM to hold the number of
1355 kB you want to reserve for pRAM. You can overwrite
1356 this default value by defining an environment
1357 variable "pram" to the number of kB you want to
1358 reserve. Note that the board info structure will
1359 still show the full amount of RAM. If pRAM is
1360 reserved, a new environment variable "mem" will
1361 automatically be defined to hold the amount of
1362 remaining RAM in a form that can be passed as boot
1363 argument to Linux, for instance like that:
1365 setenv bootargs ... mem=\$(mem)
1368 This way you can tell Linux not to use this memory,
1369 either, which results in a memory region that will
1370 not be affected by reboots.
1372 *WARNING* If your board configuration uses automatic
1373 detection of the RAM size, you must make sure that
1374 this memory test is non-destructive. So far, the
1375 following board configurations are known to be
1378 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1379 HERMES, IP860, RPXlite, LWMON, LANTEC,
1380 PCU_E, FLAGADM, TQM8260
1385 Define this variable to stop the system in case of a
1386 fatal error, so that you have to reset it manually.
1387 This is probably NOT a good idea for an embedded
1388 system where you want to system to reboot
1389 automatically as fast as possible, but it may be
1390 useful during development since you can try to debug
1391 the conditions that lead to the situation.
1393 CONFIG_NET_RETRY_COUNT
1395 This variable defines the number of retries for
1396 network operations like ARP, RARP, TFTP, or BOOTP
1397 before giving up the operation. If not defined, a
1398 default value of 5 is used.
1400 - Command Interpreter:
1403 Enable auto completion of commands using TAB.
1407 Define this variable to enable the "hush" shell (from
1408 Busybox) as command line interpreter, thus enabling
1409 powerful command line syntax like
1410 if...then...else...fi conditionals or `&&' and '||'
1411 constructs ("shell scripts").
1413 If undefined, you get the old, much simpler behaviour
1414 with a somewhat smaller memory footprint.
1419 This defines the secondary prompt string, which is
1420 printed when the command interpreter needs more input
1421 to complete a command. Usually "> ".
1425 In the current implementation, the local variables
1426 space and global environment variables space are
1427 separated. Local variables are those you define by
1428 simply typing `name=value'. To access a local
1429 variable later on, you have write `$name' or
1430 `${name}'; to execute the contents of a variable
1431 directly type `$name' at the command prompt.
1433 Global environment variables are those you use
1434 setenv/printenv to work with. To run a command stored
1435 in such a variable, you need to use the run command,
1436 and you must not use the '$' sign to access them.
1438 To store commands and special characters in a
1439 variable, please use double quotation marks
1440 surrounding the whole text of the variable, instead
1441 of the backslashes before semicolons and special
1444 - Default Environment:
1445 CONFIG_EXTRA_ENV_SETTINGS
1447 Define this to contain any number of null terminated
1448 strings (variable = value pairs) that will be part of
1449 the default environment compiled into the boot image.
1451 For example, place something like this in your
1452 board's config file:
1454 #define CONFIG_EXTRA_ENV_SETTINGS \
1458 Warning: This method is based on knowledge about the
1459 internal format how the environment is stored by the
1460 U-Boot code. This is NOT an official, exported
1461 interface! Although it is unlikely that this format
1462 will change soon, there is no guarantee either.
1463 You better know what you are doing here.
1465 Note: overly (ab)use of the default environment is
1466 discouraged. Make sure to check other ways to preset
1467 the environment like the autoscript function or the
1470 - DataFlash Support:
1471 CONFIG_HAS_DATAFLASH
1473 Defining this option enables DataFlash features and
1474 allows to read/write in Dataflash via the standard
1477 - SystemACE Support:
1480 Adding this option adds support for Xilinx SystemACE
1481 chips attached via some sort of local bus. The address
1482 of the chip must alsh be defined in the
1483 CFG_SYSTEMACE_BASE macro. For example:
1485 #define CONFIG_SYSTEMACE
1486 #define CFG_SYSTEMACE_BASE 0xf0000000
1488 When SystemACE support is added, the "ace" device type
1489 becomes available to the fat commands, i.e. fatls.
1491 - TFTP Fixed UDP Port:
1494 If this is defined, the environment variable tftpsrcp
1495 is used to supply the TFTP UDP source port value.
1496 If tftpsrcp isn't defined, the normal pseudo-random port
1497 number generator is used.
1499 Also, the environment variable tftpdstp is used to supply
1500 the TFTP UDP destination port value. If tftpdstp isn't
1501 defined, the normal port 69 is used.
1503 The purpose for tftpsrcp is to allow a TFTP server to
1504 blindly start the TFTP transfer using the pre-configured
1505 target IP address and UDP port. This has the effect of
1506 "punching through" the (Windows XP) firewall, allowing
1507 the remainder of the TFTP transfer to proceed normally.
1508 A better solution is to properly configure the firewall,
1509 but sometimes that is not allowed.
1511 - Show boot progress:
1512 CONFIG_SHOW_BOOT_PROGRESS
1514 Defining this option allows to add some board-
1515 specific code (calling a user-provided function
1516 "show_boot_progress(int)") that enables you to show
1517 the system's boot progress on some display (for
1518 example, some LED's) on your board. At the moment,
1519 the following checkpoints are implemented:
1522 1 common/cmd_bootm.c before attempting to boot an image
1523 -1 common/cmd_bootm.c Image header has bad magic number
1524 2 common/cmd_bootm.c Image header has correct magic number
1525 -2 common/cmd_bootm.c Image header has bad checksum
1526 3 common/cmd_bootm.c Image header has correct checksum
1527 -3 common/cmd_bootm.c Image data has bad checksum
1528 4 common/cmd_bootm.c Image data has correct checksum
1529 -4 common/cmd_bootm.c Image is for unsupported architecture
1530 5 common/cmd_bootm.c Architecture check OK
1531 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1532 6 common/cmd_bootm.c Image Type check OK
1533 -6 common/cmd_bootm.c gunzip uncompression error
1534 -7 common/cmd_bootm.c Unimplemented compression type
1535 7 common/cmd_bootm.c Uncompression OK
1536 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1537 8 common/cmd_bootm.c Image Type check OK
1538 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1539 9 common/cmd_bootm.c Start initial ramdisk verification
1540 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1541 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1542 10 common/cmd_bootm.c Ramdisk header is OK
1543 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1544 11 common/cmd_bootm.c Ramdisk data has correct checksum
1545 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1546 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1547 13 common/cmd_bootm.c Start multifile image verification
1548 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1549 15 common/cmd_bootm.c All preparation done, transferring control to OS
1551 -30 lib_ppc/board.c Fatal error, hang the system
1552 -31 post/post.c POST test failed, detected by post_output_backlog()
1553 -32 post/post.c POST test failed, detected by post_run_single()
1555 -1 common/cmd_doc.c Bad usage of "doc" command
1556 -1 common/cmd_doc.c No boot device
1557 -1 common/cmd_doc.c Unknown Chip ID on boot device
1558 -1 common/cmd_doc.c Read Error on boot device
1559 -1 common/cmd_doc.c Image header has bad magic number
1561 -1 common/cmd_ide.c Bad usage of "ide" command
1562 -1 common/cmd_ide.c No boot device
1563 -1 common/cmd_ide.c Unknown boot device
1564 -1 common/cmd_ide.c Unknown partition table
1565 -1 common/cmd_ide.c Invalid partition type
1566 -1 common/cmd_ide.c Read Error on boot device
1567 -1 common/cmd_ide.c Image header has bad magic number
1569 -1 common/cmd_nand.c Bad usage of "nand" command
1570 -1 common/cmd_nand.c No boot device
1571 -1 common/cmd_nand.c Unknown Chip ID on boot device
1572 -1 common/cmd_nand.c Read Error on boot device
1573 -1 common/cmd_nand.c Image header has bad magic number
1575 -1 common/env_common.c Environment has a bad CRC, using default
1581 [so far only for SMDK2400 and TRAB boards]
1583 - Modem support endable:
1584 CONFIG_MODEM_SUPPORT
1586 - RTS/CTS Flow control enable:
1589 - Modem debug support:
1590 CONFIG_MODEM_SUPPORT_DEBUG
1592 Enables debugging stuff (char screen[1024], dbg())
1593 for modem support. Useful only with BDI2000.
1595 - Interrupt support (PPC):
1597 There are common interrupt_init() and timer_interrupt()
1598 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1599 for cpu specific initialization. interrupt_init_cpu()
1600 should set decrementer_count to appropriate value. If
1601 cpu resets decrementer automatically after interrupt
1602 (ppc4xx) it should set decrementer_count to zero.
1603 timer_interrupt() calls timer_interrupt_cpu() for cpu
1604 specific handling. If board has watchdog / status_led
1605 / other_activity_monitor it works automatically from
1606 general timer_interrupt().
1610 In the target system modem support is enabled when a
1611 specific key (key combination) is pressed during
1612 power-on. Otherwise U-Boot will boot normally
1613 (autoboot). The key_pressed() fuction is called from
1614 board_init(). Currently key_pressed() is a dummy
1615 function, returning 1 and thus enabling modem
1618 If there are no modem init strings in the
1619 environment, U-Boot proceed to autoboot; the
1620 previous output (banner, info printfs) will be
1623 See also: doc/README.Modem
1626 Configuration Settings:
1627 -----------------------
1629 - CFG_LONGHELP: Defined when you want long help messages included;
1630 undefine this when you're short of memory.
1632 - CFG_PROMPT: This is what U-Boot prints on the console to
1633 prompt for user input.
1635 - CFG_CBSIZE: Buffer size for input from the Console
1637 - CFG_PBSIZE: Buffer size for Console output
1639 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1641 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1642 the application (usually a Linux kernel) when it is
1645 - CFG_BAUDRATE_TABLE:
1646 List of legal baudrate settings for this board.
1648 - CFG_CONSOLE_INFO_QUIET
1649 Suppress display of console information at boot.
1651 - CFG_CONSOLE_IS_IN_ENV
1652 If the board specific function
1653 extern int overwrite_console (void);
1654 returns 1, the stdin, stderr and stdout are switched to the
1655 serial port, else the settings in the environment are used.
1657 - CFG_CONSOLE_OVERWRITE_ROUTINE
1658 Enable the call to overwrite_console().
1660 - CFG_CONSOLE_ENV_OVERWRITE
1661 Enable overwrite of previous console environment settings.
1663 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1664 Begin and End addresses of the area used by the
1668 Enable an alternate, more extensive memory test.
1670 - CFG_MEMTEST_SCRATCH:
1671 Scratch address used by the alternate memory test
1672 You only need to set this if address zero isn't writeable
1674 - CFG_TFTP_LOADADDR:
1675 Default load address for network file downloads
1677 - CFG_LOADS_BAUD_CHANGE:
1678 Enable temporary baudrate change while serial download
1681 Physical start address of SDRAM. _Must_ be 0 here.
1684 Physical start address of Motherboard I/O (if using a
1688 Physical start address of Flash memory.
1691 Physical start address of boot monitor code (set by
1692 make config files to be same as the text base address
1693 (TEXT_BASE) used when linking) - same as
1694 CFG_FLASH_BASE when booting from flash.
1697 Size of memory reserved for monitor code, used to
1698 determine _at_compile_time_ (!) if the environment is
1699 embedded within the U-Boot image, or in a separate
1703 Size of DRAM reserved for malloc() use.
1706 Maximum size of memory mapped by the startup code of
1707 the Linux kernel; all data that must be processed by
1708 the Linux kernel (bd_info, boot arguments, eventually
1709 initrd image) must be put below this limit.
1711 - CFG_MAX_FLASH_BANKS:
1712 Max number of Flash memory banks
1714 - CFG_MAX_FLASH_SECT:
1715 Max number of sectors on a Flash chip
1717 - CFG_FLASH_ERASE_TOUT:
1718 Timeout for Flash erase operations (in ms)
1720 - CFG_FLASH_WRITE_TOUT:
1721 Timeout for Flash write operations (in ms)
1723 - CFG_FLASH_LOCK_TOUT
1724 Timeout for Flash set sector lock bit operation (in ms)
1726 - CFG_FLASH_UNLOCK_TOUT
1727 Timeout for Flash clear lock bits operation (in ms)
1729 - CFG_FLASH_PROTECTION
1730 If defined, hardware flash sectors protection is used
1731 instead of U-Boot software protection.
1733 - CFG_DIRECT_FLASH_TFTP:
1735 Enable TFTP transfers directly to flash memory;
1736 without this option such a download has to be
1737 performed in two steps: (1) download to RAM, and (2)
1738 copy from RAM to flash.
1740 The two-step approach is usually more reliable, since
1741 you can check if the download worked before you erase
1742 the flash, but in some situations (when sytem RAM is
1743 too limited to allow for a tempory copy of the
1744 downloaded image) this option may be very useful.
1747 Define if the flash driver uses extra elements in the
1748 common flash structure for storing flash geometry.
1750 - CFG_FLASH_CFI_DRIVER
1751 This option also enables the building of the cfi_flash driver
1752 in the drivers directory
1754 - CFG_RX_ETH_BUFFER:
1755 Defines the number of ethernet receive buffers. On some
1756 ethernet controllers it is recommended to set this value
1757 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1758 buffers can be full shortly after enabling the interface
1759 on high ethernet traffic.
1760 Defaults to 4 if not defined.
1762 The following definitions that deal with the placement and management
1763 of environment data (variable area); in general, we support the
1764 following configurations:
1766 - CFG_ENV_IS_IN_FLASH:
1768 Define this if the environment is in flash memory.
1770 a) The environment occupies one whole flash sector, which is
1771 "embedded" in the text segment with the U-Boot code. This
1772 happens usually with "bottom boot sector" or "top boot
1773 sector" type flash chips, which have several smaller
1774 sectors at the start or the end. For instance, such a
1775 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1776 such a case you would place the environment in one of the
1777 4 kB sectors - with U-Boot code before and after it. With
1778 "top boot sector" type flash chips, you would put the
1779 environment in one of the last sectors, leaving a gap
1780 between U-Boot and the environment.
1784 Offset of environment data (variable area) to the
1785 beginning of flash memory; for instance, with bottom boot
1786 type flash chips the second sector can be used: the offset
1787 for this sector is given here.
1789 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1793 This is just another way to specify the start address of
1794 the flash sector containing the environment (instead of
1797 - CFG_ENV_SECT_SIZE:
1799 Size of the sector containing the environment.
1802 b) Sometimes flash chips have few, equal sized, BIG sectors.
1803 In such a case you don't want to spend a whole sector for
1808 If you use this in combination with CFG_ENV_IS_IN_FLASH
1809 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1810 of this flash sector for the environment. This saves
1811 memory for the RAM copy of the environment.
1813 It may also save flash memory if you decide to use this
1814 when your environment is "embedded" within U-Boot code,
1815 since then the remainder of the flash sector could be used
1816 for U-Boot code. It should be pointed out that this is
1817 STRONGLY DISCOURAGED from a robustness point of view:
1818 updating the environment in flash makes it always
1819 necessary to erase the WHOLE sector. If something goes
1820 wrong before the contents has been restored from a copy in
1821 RAM, your target system will be dead.
1823 - CFG_ENV_ADDR_REDUND
1826 These settings describe a second storage area used to hold
1827 a redundand copy of the environment data, so that there is
1828 a valid backup copy in case there is a power failure during
1829 a "saveenv" operation.
1831 BE CAREFUL! Any changes to the flash layout, and some changes to the
1832 source code will make it necessary to adapt <board>/u-boot.lds*
1836 - CFG_ENV_IS_IN_NVRAM:
1838 Define this if you have some non-volatile memory device
1839 (NVRAM, battery buffered SRAM) which you want to use for the
1845 These two #defines are used to determin the memory area you
1846 want to use for environment. It is assumed that this memory
1847 can just be read and written to, without any special
1850 BE CAREFUL! The first access to the environment happens quite early
1851 in U-Boot initalization (when we try to get the setting of for the
1852 console baudrate). You *MUST* have mappend your NVRAM area then, or
1855 Please note that even with NVRAM we still use a copy of the
1856 environment in RAM: we could work on NVRAM directly, but we want to
1857 keep settings there always unmodified except somebody uses "saveenv"
1858 to save the current settings.
1861 - CFG_ENV_IS_IN_EEPROM:
1863 Use this if you have an EEPROM or similar serial access
1864 device and a driver for it.
1869 These two #defines specify the offset and size of the
1870 environment area within the total memory of your EEPROM.
1872 - CFG_I2C_EEPROM_ADDR:
1873 If defined, specified the chip address of the EEPROM device.
1874 The default address is zero.
1876 - CFG_EEPROM_PAGE_WRITE_BITS:
1877 If defined, the number of bits used to address bytes in a
1878 single page in the EEPROM device. A 64 byte page, for example
1879 would require six bits.
1881 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1882 If defined, the number of milliseconds to delay between
1883 page writes. The default is zero milliseconds.
1885 - CFG_I2C_EEPROM_ADDR_LEN:
1886 The length in bytes of the EEPROM memory array address. Note
1887 that this is NOT the chip address length!
1889 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1890 EEPROM chips that implement "address overflow" are ones
1891 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1892 address and the extra bits end up in the "chip address" bit
1893 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1896 Note that we consider the length of the address field to
1897 still be one byte because the extra address bits are hidden
1898 in the chip address.
1901 The size in bytes of the EEPROM device.
1904 - CFG_ENV_IS_IN_DATAFLASH:
1906 Define this if you have a DataFlash memory device which you
1907 want to use for the environment.
1913 These three #defines specify the offset and size of the
1914 environment area within the total memory of your DataFlash placed
1915 at the specified address.
1917 - CFG_ENV_IS_IN_NAND:
1919 Define this if you have a NAND device which you want to use
1920 for the environment.
1925 These two #defines specify the offset and size of the environment
1926 area within the first NAND device.
1928 - CFG_SPI_INIT_OFFSET
1930 Defines offset to the initial SPI buffer area in DPRAM. The
1931 area is used at an early stage (ROM part) if the environment
1932 is configured to reside in the SPI EEPROM: We need a 520 byte
1933 scratch DPRAM area. It is used between the two initialization
1934 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1935 to be a good choice since it makes it far enough from the
1936 start of the data area as well as from the stack pointer.
1938 Please note that the environment is read-only as long as the monitor
1939 has been relocated to RAM and a RAM copy of the environment has been
1940 created; also, when using EEPROM you will have to use getenv_r()
1941 until then to read environment variables.
1943 The environment is protected by a CRC32 checksum. Before the monitor
1944 is relocated into RAM, as a result of a bad CRC you will be working
1945 with the compiled-in default environment - *silently*!!! [This is
1946 necessary, because the first environment variable we need is the
1947 "baudrate" setting for the console - if we have a bad CRC, we don't
1948 have any device yet where we could complain.]
1950 Note: once the monitor has been relocated, then it will complain if
1951 the default environment is used; a new CRC is computed as soon as you
1952 use the "saveenv" command to store a valid environment.
1954 - CFG_FAULT_ECHO_LINK_DOWN:
1955 Echo the inverted Ethernet link state to the fault LED.
1957 Note: If this option is active, then CFG_FAULT_MII_ADDR
1958 also needs to be defined.
1960 - CFG_FAULT_MII_ADDR:
1961 MII address of the PHY to check for the Ethernet link state.
1963 - CFG_64BIT_VSPRINTF:
1964 Makes vsprintf (and all *printf functions) support printing
1965 of 64bit values by using the L quantifier
1967 - CFG_64BIT_STRTOUL:
1968 Adds simple_strtoull that returns a 64bit value
1970 Low Level (hardware related) configuration options:
1971 ---------------------------------------------------
1973 - CFG_CACHELINE_SIZE:
1974 Cache Line Size of the CPU.
1977 Default address of the IMMR after system reset.
1979 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1980 and RPXsuper) to be able to adjust the position of
1981 the IMMR register after a reset.
1983 - Floppy Disk Support:
1984 CFG_FDC_DRIVE_NUMBER
1986 the default drive number (default value 0)
1990 defines the spacing between fdc chipset registers
1995 defines the offset of register from address. It
1996 depends on which part of the data bus is connected to
1997 the fdc chipset. (default value 0)
1999 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
2000 CFG_FDC_DRIVE_NUMBER are undefined, they take their
2003 if CFG_FDC_HW_INIT is defined, then the function
2004 fdc_hw_init() is called at the beginning of the FDC
2005 setup. fdc_hw_init() must be provided by the board
2006 source code. It is used to make hardware dependant
2009 - CFG_IMMR: Physical address of the Internal Memory.
2010 DO NOT CHANGE unless you know exactly what you're
2011 doing! (11-4) [MPC8xx/82xx systems only]
2013 - CFG_INIT_RAM_ADDR:
2015 Start address of memory area that can be used for
2016 initial data and stack; please note that this must be
2017 writable memory that is working WITHOUT special
2018 initialization, i. e. you CANNOT use normal RAM which
2019 will become available only after programming the
2020 memory controller and running certain initialization
2023 U-Boot uses the following memory types:
2024 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2025 - MPC824X: data cache
2026 - PPC4xx: data cache
2028 - CFG_GBL_DATA_OFFSET:
2030 Offset of the initial data structure in the memory
2031 area defined by CFG_INIT_RAM_ADDR. Usually
2032 CFG_GBL_DATA_OFFSET is chosen such that the initial
2033 data is located at the end of the available space
2034 (sometimes written as (CFG_INIT_RAM_END -
2035 CFG_INIT_DATA_SIZE), and the initial stack is just
2036 below that area (growing from (CFG_INIT_RAM_ADDR +
2037 CFG_GBL_DATA_OFFSET) downward.
2040 On the MPC824X (or other systems that use the data
2041 cache for initial memory) the address chosen for
2042 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2043 point to an otherwise UNUSED address space between
2044 the top of RAM and the start of the PCI space.
2046 - CFG_SIUMCR: SIU Module Configuration (11-6)
2048 - CFG_SYPCR: System Protection Control (11-9)
2050 - CFG_TBSCR: Time Base Status and Control (11-26)
2052 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2054 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2056 - CFG_SCCR: System Clock and reset Control Register (15-27)
2058 - CFG_OR_TIMING_SDRAM:
2062 periodic timer for refresh
2064 - CFG_DER: Debug Event Register (37-47)
2066 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2067 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2068 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2070 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2072 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2073 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2074 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2075 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2077 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2078 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2079 Machine Mode Register and Memory Periodic Timer
2080 Prescaler definitions (SDRAM timing)
2082 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2083 enable I2C microcode relocation patch (MPC8xx);
2084 define relocation offset in DPRAM [DSP2]
2086 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2087 enable SPI microcode relocation patch (MPC8xx);
2088 define relocation offset in DPRAM [SCC4]
2091 Use OSCM clock mode on MBX8xx board. Be careful,
2092 wrong setting might damage your board. Read
2093 doc/README.MBX before setting this variable!
2095 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2096 Offset of the bootmode word in DPRAM used by post
2097 (Power On Self Tests). This definition overrides
2098 #define'd default value in commproc.h resp.
2101 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2102 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2103 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2104 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2105 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2106 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2107 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2108 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2109 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2111 - CONFIG_ETHER_ON_FEC[12]
2112 Define to enable FEC[12] on a 8xx series processor.
2114 - CONFIG_FEC[12]_PHY
2115 Define to the hardcoded PHY address which corresponds
2116 to the given FEC; i. e.
2117 #define CONFIG_FEC1_PHY 4
2118 means that the PHY with address 4 is connected to FEC1
2120 When set to -1, means to probe for first available.
2122 - CONFIG_FEC[12]_PHY_NORXERR
2123 The PHY does not have a RXERR line (RMII only).
2124 (so program the FEC to ignore it).
2127 Enable RMII mode for all FECs.
2128 Note that this is a global option, we can't
2129 have one FEC in standard MII mode and another in RMII mode.
2131 - CONFIG_CRC32_VERIFY
2132 Add a verify option to the crc32 command.
2135 => crc32 -v <address> <count> <crc32>
2137 Where address/count indicate a memory area
2138 and crc32 is the correct crc32 which the
2142 Add the "loopw" memory command. This only takes effect if
2143 the memory commands are activated globally (CFG_CMD_MEM).
2146 Add the "mdc" and "mwc" memory commands. These are cyclic
2151 This command will print 4 bytes (10,11,12,13) each 500 ms.
2153 => mwc.l 100 12345678 10
2154 This command will write 12345678 to address 100 all 10 ms.
2156 This only takes effect if the memory commands are activated
2157 globally (CFG_CMD_MEM).
2159 - CONFIG_SKIP_LOWLEVEL_INIT
2160 - CONFIG_SKIP_RELOCATE_UBOOT
2162 [ARM only] If these variables are defined, then
2163 certain low level initializations (like setting up
2164 the memory controller) are omitted and/or U-Boot does
2165 not relocate itself into RAM.
2166 Normally these variables MUST NOT be defined. The
2167 only exception is when U-Boot is loaded (to RAM) by
2168 some other boot loader or by a debugger which
2169 performs these intializations itself.
2172 Building the Software:
2173 ======================
2175 Building U-Boot has been tested in native PPC environments (on a
2176 PowerBook G3 running LinuxPPC 2000) and in cross environments
2177 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2180 If you are not using a native PPC environment, it is assumed that you
2181 have the GNU cross compiling tools available in your path and named
2182 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2183 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2184 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2187 CROSS_COMPILE = ppc_4xx-
2190 U-Boot is intended to be simple to build. After installing the
2191 sources you must configure U-Boot for one specific board type. This
2196 where "NAME_config" is the name of one of the existing
2197 configurations; the following names are supported:
2199 ADCIOP_config FPS860L_config omap730p2_config
2200 ADS860_config GEN860T_config pcu_e_config
2202 AR405_config GENIETV_config PIP405_config
2203 at91rm9200dk_config GTH_config QS823_config
2204 CANBT_config hermes_config QS850_config
2205 cmi_mpc5xx_config hymod_config QS860T_config
2206 cogent_common_config IP860_config RPXlite_config
2207 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2208 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2209 CPCI405_config JSE_config rsdproto_config
2210 CPCIISER4_config LANTEC_config Sandpoint8240_config
2211 csb272_config lwmon_config sbc8260_config
2212 CU824_config MBX860T_config sbc8560_33_config
2213 DUET_ADS_config MBX_config sbc8560_66_config
2214 EBONY_config MPC8260ADS_config SM850_config
2215 ELPT860_config MPC8540ADS_config SPD823TS_config
2216 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2217 ETX094_config MPC8560ADS_config SXNI855T_config
2218 FADS823_config NETVIA_config TQM823L_config
2219 FADS850SAR_config omap1510inn_config TQM850L_config
2220 FADS860T_config omap1610h2_config TQM855L_config
2221 FPS850L_config omap1610inn_config TQM860L_config
2222 omap5912osk_config walnut_config
2223 omap2420h4_config Yukon8220_config
2226 Note: for some board special configuration names may exist; check if
2227 additional information is available from the board vendor; for
2228 instance, the TQM823L systems are available without (standard)
2229 or with LCD support. You can select such additional "features"
2230 when chosing the configuration, i. e.
2233 - will configure for a plain TQM823L, i. e. no LCD support
2235 make TQM823L_LCD_config
2236 - will configure for a TQM823L with U-Boot console on LCD
2241 Finally, type "make all", and you should get some working U-Boot
2242 images ready for download to / installation on your system:
2244 - "u-boot.bin" is a raw binary image
2245 - "u-boot" is an image in ELF binary format
2246 - "u-boot.srec" is in Motorola S-Record format
2249 Please be aware that the Makefiles assume you are using GNU make, so
2250 for instance on NetBSD you might need to use "gmake" instead of
2254 If the system board that you have is not listed, then you will need
2255 to port U-Boot to your hardware platform. To do this, follow these
2258 1. Add a new configuration option for your board to the toplevel
2259 "Makefile" and to the "MAKEALL" script, using the existing
2260 entries as examples. Note that here and at many other places
2261 boards and other names are listed in alphabetical sort order. Please
2263 2. Create a new directory to hold your board specific code. Add any
2264 files you need. In your board directory, you will need at least
2265 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2266 3. Create a new configuration file "include/configs/<board>.h" for
2268 3. If you're porting U-Boot to a new CPU, then also create a new
2269 directory to hold your CPU specific code. Add any files you need.
2270 4. Run "make <board>_config" with your new name.
2271 5. Type "make", and you should get a working "u-boot.srec" file
2272 to be installed on your target system.
2273 6. Debug and solve any problems that might arise.
2274 [Of course, this last step is much harder than it sounds.]
2277 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2278 ==============================================================
2280 If you have modified U-Boot sources (for instance added a new board
2281 or support for new devices, a new CPU, etc.) you are expected to
2282 provide feedback to the other developers. The feedback normally takes
2283 the form of a "patch", i. e. a context diff against a certain (latest
2284 official or latest in CVS) version of U-Boot sources.
2286 But before you submit such a patch, please verify that your modifi-
2287 cation did not break existing code. At least make sure that *ALL* of
2288 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2289 just run the "MAKEALL" script, which will configure and build U-Boot
2290 for ALL supported system. Be warned, this will take a while. You can
2291 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2292 environment variable to the script, i. e. to use the cross tools from
2293 MontaVista's Hard Hat Linux you can type
2295 CROSS_COMPILE=ppc_8xx- MAKEALL
2297 or to build on a native PowerPC system you can type
2299 CROSS_COMPILE=' ' MAKEALL
2301 See also "U-Boot Porting Guide" below.
2304 Monitor Commands - Overview:
2305 ============================
2307 go - start application at address 'addr'
2308 run - run commands in an environment variable
2309 bootm - boot application image from memory
2310 bootp - boot image via network using BootP/TFTP protocol
2311 tftpboot- boot image via network using TFTP protocol
2312 and env variables "ipaddr" and "serverip"
2313 (and eventually "gatewayip")
2314 rarpboot- boot image via network using RARP/TFTP protocol
2315 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2316 loads - load S-Record file over serial line
2317 loadb - load binary file over serial line (kermit mode)
2319 mm - memory modify (auto-incrementing)
2320 nm - memory modify (constant address)
2321 mw - memory write (fill)
2323 cmp - memory compare
2324 crc32 - checksum calculation
2325 imd - i2c memory display
2326 imm - i2c memory modify (auto-incrementing)
2327 inm - i2c memory modify (constant address)
2328 imw - i2c memory write (fill)
2329 icrc32 - i2c checksum calculation
2330 iprobe - probe to discover valid I2C chip addresses
2331 iloop - infinite loop on address range
2332 isdram - print SDRAM configuration information
2333 sspi - SPI utility commands
2334 base - print or set address offset
2335 printenv- print environment variables
2336 setenv - set environment variables
2337 saveenv - save environment variables to persistent storage
2338 protect - enable or disable FLASH write protection
2339 erase - erase FLASH memory
2340 flinfo - print FLASH memory information
2341 bdinfo - print Board Info structure
2342 iminfo - print header information for application image
2343 coninfo - print console devices and informations
2344 ide - IDE sub-system
2345 loop - infinite loop on address range
2346 loopw - infinite write loop on address range
2347 mtest - simple RAM test
2348 icache - enable or disable instruction cache
2349 dcache - enable or disable data cache
2350 reset - Perform RESET of the CPU
2351 echo - echo args to console
2352 version - print monitor version
2353 help - print online help
2354 ? - alias for 'help'
2357 Monitor Commands - Detailed Description:
2358 ========================================
2362 For now: just type "help <command>".
2365 Environment Variables:
2366 ======================
2368 U-Boot supports user configuration using Environment Variables which
2369 can be made persistent by saving to Flash memory.
2371 Environment Variables are set using "setenv", printed using
2372 "printenv", and saved to Flash using "saveenv". Using "setenv"
2373 without a value can be used to delete a variable from the
2374 environment. As long as you don't save the environment you are
2375 working with an in-memory copy. In case the Flash area containing the
2376 environment is erased by accident, a default environment is provided.
2378 Some configuration options can be set using Environment Variables:
2380 baudrate - see CONFIG_BAUDRATE
2382 bootdelay - see CONFIG_BOOTDELAY
2384 bootcmd - see CONFIG_BOOTCOMMAND
2386 bootargs - Boot arguments when booting an RTOS image
2388 bootfile - Name of the image to load with TFTP
2390 autoload - if set to "no" (any string beginning with 'n'),
2391 "bootp" will just load perform a lookup of the
2392 configuration from the BOOTP server, but not try to
2393 load any image using TFTP
2395 autostart - if set to "yes", an image loaded using the "bootp",
2396 "rarpboot", "tftpboot" or "diskboot" commands will
2397 be automatically started (by internally calling
2400 If set to "no", a standalone image passed to the
2401 "bootm" command will be copied to the load address
2402 (and eventually uncompressed), but NOT be started.
2403 This can be used to load and uncompress arbitrary
2406 i2cfast - (PPC405GP|PPC405EP only)
2407 if set to 'y' configures Linux I2C driver for fast
2408 mode (400kHZ). This environment variable is used in
2409 initialization code. So, for changes to be effective
2410 it must be saved and board must be reset.
2412 initrd_high - restrict positioning of initrd images:
2413 If this variable is not set, initrd images will be
2414 copied to the highest possible address in RAM; this
2415 is usually what you want since it allows for
2416 maximum initrd size. If for some reason you want to
2417 make sure that the initrd image is loaded below the
2418 CFG_BOOTMAPSZ limit, you can set this environment
2419 variable to a value of "no" or "off" or "0".
2420 Alternatively, you can set it to a maximum upper
2421 address to use (U-Boot will still check that it
2422 does not overwrite the U-Boot stack and data).
2424 For instance, when you have a system with 16 MB
2425 RAM, and want to reserve 4 MB from use by Linux,
2426 you can do this by adding "mem=12M" to the value of
2427 the "bootargs" variable. However, now you must make
2428 sure that the initrd image is placed in the first
2429 12 MB as well - this can be done with
2431 setenv initrd_high 00c00000
2433 If you set initrd_high to 0xFFFFFFFF, this is an
2434 indication to U-Boot that all addresses are legal
2435 for the Linux kernel, including addresses in flash
2436 memory. In this case U-Boot will NOT COPY the
2437 ramdisk at all. This may be useful to reduce the
2438 boot time on your system, but requires that this
2439 feature is supported by your Linux kernel.
2441 ipaddr - IP address; needed for tftpboot command
2443 loadaddr - Default load address for commands like "bootp",
2444 "rarpboot", "tftpboot", "loadb" or "diskboot"
2446 loads_echo - see CONFIG_LOADS_ECHO
2448 serverip - TFTP server IP address; needed for tftpboot command
2450 bootretry - see CONFIG_BOOT_RETRY_TIME
2452 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2454 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2456 ethprime - When CONFIG_NET_MULTI is enabled controls which
2457 interface is used first.
2459 ethact - When CONFIG_NET_MULTI is enabled controls which
2460 interface is currently active. For example you
2461 can do the following
2463 => setenv ethact FEC ETHERNET
2464 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2465 => setenv ethact SCC ETHERNET
2466 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2468 netretry - When set to "no" each network operation will
2469 either succeed or fail without retrying.
2470 When set to "once" the network operation will
2471 fail when all the available network interfaces
2472 are tried once without success.
2473 Useful on scripts which control the retry operation
2476 tftpsrcport - If this is set, the value is used for TFTP's
2479 tftpdstport - If this is set, the value is used for TFTP's UDP
2480 destination port instead of the Well Know Port 69.
2482 vlan - When set to a value < 4095 the traffic over
2483 ethernet is encapsulated/received over 802.1q
2486 The following environment variables may be used and automatically
2487 updated by the network boot commands ("bootp" and "rarpboot"),
2488 depending the information provided by your boot server:
2490 bootfile - see above
2491 dnsip - IP address of your Domain Name Server
2492 dnsip2 - IP address of your secondary Domain Name Server
2493 gatewayip - IP address of the Gateway (Router) to use
2494 hostname - Target hostname
2496 netmask - Subnet Mask
2497 rootpath - Pathname of the root filesystem on the NFS server
2498 serverip - see above
2501 There are two special Environment Variables:
2503 serial# - contains hardware identification information such
2504 as type string and/or serial number
2505 ethaddr - Ethernet address
2507 These variables can be set only once (usually during manufacturing of
2508 the board). U-Boot refuses to delete or overwrite these variables
2509 once they have been set once.
2512 Further special Environment Variables:
2514 ver - Contains the U-Boot version string as printed
2515 with the "version" command. This variable is
2516 readonly (see CONFIG_VERSION_VARIABLE).
2519 Please note that changes to some configuration parameters may take
2520 only effect after the next boot (yes, that's just like Windoze :-).
2523 Command Line Parsing:
2524 =====================
2526 There are two different command line parsers available with U-Boot:
2527 the old "simple" one, and the much more powerful "hush" shell:
2529 Old, simple command line parser:
2530 --------------------------------
2532 - supports environment variables (through setenv / saveenv commands)
2533 - several commands on one line, separated by ';'
2534 - variable substitution using "... $(name) ..." syntax
2535 - special characters ('$', ';') can be escaped by prefixing with '\',
2537 setenv bootcmd bootm \$(address)
2538 - You can also escape text by enclosing in single apostrophes, for example:
2539 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2544 - similar to Bourne shell, with control structures like
2545 if...then...else...fi, for...do...done; while...do...done,
2546 until...do...done, ...
2547 - supports environment ("global") variables (through setenv / saveenv
2548 commands) and local shell variables (through standard shell syntax
2549 "name=value"); only environment variables can be used with "run"
2555 (1) If a command line (or an environment variable executed by a "run"
2556 command) contains several commands separated by semicolon, and
2557 one of these commands fails, then the remaining commands will be
2560 (2) If you execute several variables with one call to run (i. e.
2561 calling run with a list af variables as arguments), any failing
2562 command will cause "run" to terminate, i. e. the remaining
2563 variables are not executed.
2565 Note for Redundant Ethernet Interfaces:
2566 =======================================
2568 Some boards come with redundant ethernet interfaces; U-Boot supports
2569 such configurations and is capable of automatic selection of a
2570 "working" interface when needed. MAC assignment works as follows:
2572 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2573 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2574 "eth1addr" (=>eth1), "eth2addr", ...
2576 If the network interface stores some valid MAC address (for instance
2577 in SROM), this is used as default address if there is NO correspon-
2578 ding setting in the environment; if the corresponding environment
2579 variable is set, this overrides the settings in the card; that means:
2581 o If the SROM has a valid MAC address, and there is no address in the
2582 environment, the SROM's address is used.
2584 o If there is no valid address in the SROM, and a definition in the
2585 environment exists, then the value from the environment variable is
2588 o If both the SROM and the environment contain a MAC address, and
2589 both addresses are the same, this MAC address is used.
2591 o If both the SROM and the environment contain a MAC address, and the
2592 addresses differ, the value from the environment is used and a
2595 o If neither SROM nor the environment contain a MAC address, an error
2602 The "boot" commands of this monitor operate on "image" files which
2603 can be basicly anything, preceeded by a special header; see the
2604 definitions in include/image.h for details; basicly, the header
2605 defines the following image properties:
2607 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2608 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2609 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2610 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2611 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2612 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2613 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2614 * Compression Type (uncompressed, gzip, bzip2)
2620 The header is marked by a special Magic Number, and both the header
2621 and the data portions of the image are secured against corruption by
2628 Although U-Boot should support any OS or standalone application
2629 easily, the main focus has always been on Linux during the design of
2632 U-Boot includes many features that so far have been part of some
2633 special "boot loader" code within the Linux kernel. Also, any
2634 "initrd" images to be used are no longer part of one big Linux image;
2635 instead, kernel and "initrd" are separate images. This implementation
2636 serves several purposes:
2638 - the same features can be used for other OS or standalone
2639 applications (for instance: using compressed images to reduce the
2640 Flash memory footprint)
2642 - it becomes much easier to port new Linux kernel versions because
2643 lots of low-level, hardware dependent stuff are done by U-Boot
2645 - the same Linux kernel image can now be used with different "initrd"
2646 images; of course this also means that different kernel images can
2647 be run with the same "initrd". This makes testing easier (you don't
2648 have to build a new "zImage.initrd" Linux image when you just
2649 change a file in your "initrd"). Also, a field-upgrade of the
2650 software is easier now.
2656 Porting Linux to U-Boot based systems:
2657 ---------------------------------------
2659 U-Boot cannot save you from doing all the necessary modifications to
2660 configure the Linux device drivers for use with your target hardware
2661 (no, we don't intend to provide a full virtual machine interface to
2664 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2666 Just make sure your machine specific header file (for instance
2667 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2668 Information structure as we define in include/u-boot.h, and make
2669 sure that your definition of IMAP_ADDR uses the same value as your
2670 U-Boot configuration in CFG_IMMR.
2673 Configuring the Linux kernel:
2674 -----------------------------
2676 No specific requirements for U-Boot. Make sure you have some root
2677 device (initial ramdisk, NFS) for your target system.
2680 Building a Linux Image:
2681 -----------------------
2683 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2684 not used. If you use recent kernel source, a new build target
2685 "uImage" will exist which automatically builds an image usable by
2686 U-Boot. Most older kernels also have support for a "pImage" target,
2687 which was introduced for our predecessor project PPCBoot and uses a
2688 100% compatible format.
2697 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2698 encapsulate a compressed Linux kernel image with header information,
2699 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2701 * build a standard "vmlinux" kernel image (in ELF binary format):
2703 * convert the kernel into a raw binary image:
2705 ${CROSS_COMPILE}-objcopy -O binary \
2706 -R .note -R .comment \
2707 -S vmlinux linux.bin
2709 * compress the binary image:
2713 * package compressed binary image for U-Boot:
2715 mkimage -A ppc -O linux -T kernel -C gzip \
2716 -a 0 -e 0 -n "Linux Kernel Image" \
2717 -d linux.bin.gz uImage
2720 The "mkimage" tool can also be used to create ramdisk images for use
2721 with U-Boot, either separated from the Linux kernel image, or
2722 combined into one file. "mkimage" encapsulates the images with a 64
2723 byte header containing information about target architecture,
2724 operating system, image type, compression method, entry points, time
2725 stamp, CRC32 checksums, etc.
2727 "mkimage" can be called in two ways: to verify existing images and
2728 print the header information, or to build new images.
2730 In the first form (with "-l" option) mkimage lists the information
2731 contained in the header of an existing U-Boot image; this includes
2732 checksum verification:
2734 tools/mkimage -l image
2735 -l ==> list image header information
2737 The second form (with "-d" option) is used to build a U-Boot image
2738 from a "data file" which is used as image payload:
2740 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2741 -n name -d data_file image
2742 -A ==> set architecture to 'arch'
2743 -O ==> set operating system to 'os'
2744 -T ==> set image type to 'type'
2745 -C ==> set compression type 'comp'
2746 -a ==> set load address to 'addr' (hex)
2747 -e ==> set entry point to 'ep' (hex)
2748 -n ==> set image name to 'name'
2749 -d ==> use image data from 'datafile'
2751 Right now, all Linux kernels for PowerPC systems use the same load
2752 address (0x00000000), but the entry point address depends on the
2755 - 2.2.x kernels have the entry point at 0x0000000C,
2756 - 2.3.x and later kernels have the entry point at 0x00000000.
2758 So a typical call to build a U-Boot image would read:
2760 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2761 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2762 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2763 > examples/uImage.TQM850L
2764 Image Name: 2.4.4 kernel for TQM850L
2765 Created: Wed Jul 19 02:34:59 2000
2766 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2767 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2768 Load Address: 0x00000000
2769 Entry Point: 0x00000000
2771 To verify the contents of the image (or check for corruption):
2773 -> tools/mkimage -l examples/uImage.TQM850L
2774 Image Name: 2.4.4 kernel for TQM850L
2775 Created: Wed Jul 19 02:34:59 2000
2776 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2777 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2778 Load Address: 0x00000000
2779 Entry Point: 0x00000000
2781 NOTE: for embedded systems where boot time is critical you can trade
2782 speed for memory and install an UNCOMPRESSED image instead: this
2783 needs more space in Flash, but boots much faster since it does not
2784 need to be uncompressed:
2786 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2787 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2788 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2789 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2790 > examples/uImage.TQM850L-uncompressed
2791 Image Name: 2.4.4 kernel for TQM850L
2792 Created: Wed Jul 19 02:34:59 2000
2793 Image Type: PowerPC Linux Kernel Image (uncompressed)
2794 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2795 Load Address: 0x00000000
2796 Entry Point: 0x00000000
2799 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2800 when your kernel is intended to use an initial ramdisk:
2802 -> tools/mkimage -n 'Simple Ramdisk Image' \
2803 > -A ppc -O linux -T ramdisk -C gzip \
2804 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2805 Image Name: Simple Ramdisk Image
2806 Created: Wed Jan 12 14:01:50 2000
2807 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2808 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2809 Load Address: 0x00000000
2810 Entry Point: 0x00000000
2813 Installing a Linux Image:
2814 -------------------------
2816 To downloading a U-Boot image over the serial (console) interface,
2817 you must convert the image to S-Record format:
2819 objcopy -I binary -O srec examples/image examples/image.srec
2821 The 'objcopy' does not understand the information in the U-Boot
2822 image header, so the resulting S-Record file will be relative to
2823 address 0x00000000. To load it to a given address, you need to
2824 specify the target address as 'offset' parameter with the 'loads'
2827 Example: install the image to address 0x40100000 (which on the
2828 TQM8xxL is in the first Flash bank):
2830 => erase 40100000 401FFFFF
2836 ## Ready for S-Record download ...
2837 ~>examples/image.srec
2838 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2840 15989 15990 15991 15992
2841 [file transfer complete]
2843 ## Start Addr = 0x00000000
2846 You can check the success of the download using the 'iminfo' command;
2847 this includes a checksum verification so you can be sure no data
2848 corruption happened:
2852 ## Checking Image at 40100000 ...
2853 Image Name: 2.2.13 for initrd on TQM850L
2854 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2855 Data Size: 335725 Bytes = 327 kB = 0 MB
2856 Load Address: 00000000
2857 Entry Point: 0000000c
2858 Verifying Checksum ... OK
2864 The "bootm" command is used to boot an application that is stored in
2865 memory (RAM or Flash). In case of a Linux kernel image, the contents
2866 of the "bootargs" environment variable is passed to the kernel as
2867 parameters. You can check and modify this variable using the
2868 "printenv" and "setenv" commands:
2871 => printenv bootargs
2872 bootargs=root=/dev/ram
2874 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2876 => printenv bootargs
2877 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2880 ## Booting Linux kernel at 40020000 ...
2881 Image Name: 2.2.13 for NFS on TQM850L
2882 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2883 Data Size: 381681 Bytes = 372 kB = 0 MB
2884 Load Address: 00000000
2885 Entry Point: 0000000c
2886 Verifying Checksum ... OK
2887 Uncompressing Kernel Image ... OK
2888 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
2889 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2890 time_init: decrementer frequency = 187500000/60
2891 Calibrating delay loop... 49.77 BogoMIPS
2892 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2895 If you want to boot a Linux kernel with initial ram disk, you pass
2896 the memory addresses of both the kernel and the initrd image (PPBCOOT
2897 format!) to the "bootm" command:
2899 => imi 40100000 40200000
2901 ## Checking Image at 40100000 ...
2902 Image Name: 2.2.13 for initrd on TQM850L
2903 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2904 Data Size: 335725 Bytes = 327 kB = 0 MB
2905 Load Address: 00000000
2906 Entry Point: 0000000c
2907 Verifying Checksum ... OK
2909 ## Checking Image at 40200000 ...
2910 Image Name: Simple Ramdisk Image
2911 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2912 Data Size: 566530 Bytes = 553 kB = 0 MB
2913 Load Address: 00000000
2914 Entry Point: 00000000
2915 Verifying Checksum ... OK
2917 => bootm 40100000 40200000
2918 ## Booting Linux kernel at 40100000 ...
2919 Image Name: 2.2.13 for initrd on TQM850L
2920 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2921 Data Size: 335725 Bytes = 327 kB = 0 MB
2922 Load Address: 00000000
2923 Entry Point: 0000000c
2924 Verifying Checksum ... OK
2925 Uncompressing Kernel Image ... OK
2926 ## Loading RAMDisk Image at 40200000 ...
2927 Image Name: Simple Ramdisk Image
2928 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2929 Data Size: 566530 Bytes = 553 kB = 0 MB
2930 Load Address: 00000000
2931 Entry Point: 00000000
2932 Verifying Checksum ... OK
2933 Loading Ramdisk ... OK
2934 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
2935 Boot arguments: root=/dev/ram
2936 time_init: decrementer frequency = 187500000/60
2937 Calibrating delay loop... 49.77 BogoMIPS
2939 RAMDISK: Compressed image found at block 0
2940 VFS: Mounted root (ext2 filesystem).
2944 More About U-Boot Image Types:
2945 ------------------------------
2947 U-Boot supports the following image types:
2949 "Standalone Programs" are directly runnable in the environment
2950 provided by U-Boot; it is expected that (if they behave
2951 well) you can continue to work in U-Boot after return from
2952 the Standalone Program.
2953 "OS Kernel Images" are usually images of some Embedded OS which
2954 will take over control completely. Usually these programs
2955 will install their own set of exception handlers, device
2956 drivers, set up the MMU, etc. - this means, that you cannot
2957 expect to re-enter U-Boot except by resetting the CPU.
2958 "RAMDisk Images" are more or less just data blocks, and their
2959 parameters (address, size) are passed to an OS kernel that is
2961 "Multi-File Images" contain several images, typically an OS
2962 (Linux) kernel image and one or more data images like
2963 RAMDisks. This construct is useful for instance when you want
2964 to boot over the network using BOOTP etc., where the boot
2965 server provides just a single image file, but you want to get
2966 for instance an OS kernel and a RAMDisk image.
2968 "Multi-File Images" start with a list of image sizes, each
2969 image size (in bytes) specified by an "uint32_t" in network
2970 byte order. This list is terminated by an "(uint32_t)0".
2971 Immediately after the terminating 0 follow the images, one by
2972 one, all aligned on "uint32_t" boundaries (size rounded up to
2973 a multiple of 4 bytes).
2975 "Firmware Images" are binary images containing firmware (like
2976 U-Boot or FPGA images) which usually will be programmed to
2979 "Script files" are command sequences that will be executed by
2980 U-Boot's command interpreter; this feature is especially
2981 useful when you configure U-Boot to use a real shell (hush)
2982 as command interpreter.
2988 One of the features of U-Boot is that you can dynamically load and
2989 run "standalone" applications, which can use some resources of
2990 U-Boot like console I/O functions or interrupt services.
2992 Two simple examples are included with the sources:
2997 'examples/hello_world.c' contains a small "Hello World" Demo
2998 application; it is automatically compiled when you build U-Boot.
2999 It's configured to run at address 0x00040004, so you can play with it
3003 ## Ready for S-Record download ...
3004 ~>examples/hello_world.srec
3005 1 2 3 4 5 6 7 8 9 10 11 ...
3006 [file transfer complete]
3008 ## Start Addr = 0x00040004
3010 => go 40004 Hello World! This is a test.
3011 ## Starting application at 0x00040004 ...
3022 Hit any key to exit ...
3024 ## Application terminated, rc = 0x0
3026 Another example, which demonstrates how to register a CPM interrupt
3027 handler with the U-Boot code, can be found in 'examples/timer.c'.
3028 Here, a CPM timer is set up to generate an interrupt every second.
3029 The interrupt service routine is trivial, just printing a '.'
3030 character, but this is just a demo program. The application can be
3031 controlled by the following keys:
3033 ? - print current values og the CPM Timer registers
3034 b - enable interrupts and start timer
3035 e - stop timer and disable interrupts
3036 q - quit application
3039 ## Ready for S-Record download ...
3040 ~>examples/timer.srec
3041 1 2 3 4 5 6 7 8 9 10 11 ...
3042 [file transfer complete]
3044 ## Start Addr = 0x00040004
3047 ## Starting application at 0x00040004 ...
3050 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3053 [q, b, e, ?] Set interval 1000000 us
3056 [q, b, e, ?] ........
3057 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3060 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3063 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3066 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3068 [q, b, e, ?] ...Stopping timer
3070 [q, b, e, ?] ## Application terminated, rc = 0x0
3076 Over time, many people have reported problems when trying to use the
3077 "minicom" terminal emulation program for serial download. I (wd)
3078 consider minicom to be broken, and recommend not to use it. Under
3079 Unix, I recommend to use C-Kermit for general purpose use (and
3080 especially for kermit binary protocol download ("loadb" command), and
3081 use "cu" for S-Record download ("loads" command).
3083 Nevertheless, if you absolutely want to use it try adding this
3084 configuration to your "File transfer protocols" section:
3086 Name Program Name U/D FullScr IO-Red. Multi
3087 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3088 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3094 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3095 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3097 Building requires a cross environment; it is known to work on
3098 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3099 need gmake since the Makefiles are not compatible with BSD make).
3100 Note that the cross-powerpc package does not install include files;
3101 attempting to build U-Boot will fail because <machine/ansi.h> is
3102 missing. This file has to be installed and patched manually:
3104 # cd /usr/pkg/cross/powerpc-netbsd/include
3106 # ln -s powerpc machine
3107 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3108 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3110 Native builds *don't* work due to incompatibilities between native
3111 and U-Boot include files.
3113 Booting assumes that (the first part of) the image booted is a
3114 stage-2 loader which in turn loads and then invokes the kernel
3115 proper. Loader sources will eventually appear in the NetBSD source
3116 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3117 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3120 Implementation Internals:
3121 =========================
3123 The following is not intended to be a complete description of every
3124 implementation detail. However, it should help to understand the
3125 inner workings of U-Boot and make it easier to port it to custom
3129 Initial Stack, Global Data:
3130 ---------------------------
3132 The implementation of U-Boot is complicated by the fact that U-Boot
3133 starts running out of ROM (flash memory), usually without access to
3134 system RAM (because the memory controller is not initialized yet).
3135 This means that we don't have writable Data or BSS segments, and BSS
3136 is not initialized as zero. To be able to get a C environment working
3137 at all, we have to allocate at least a minimal stack. Implementation
3138 options for this are defined and restricted by the CPU used: Some CPU
3139 models provide on-chip memory (like the IMMR area on MPC8xx and
3140 MPC826x processors), on others (parts of) the data cache can be
3141 locked as (mis-) used as memory, etc.
3143 Chris Hallinan posted a good summary of these issues to the
3144 u-boot-users mailing list:
3146 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3147 From: "Chris Hallinan" <clh@net1plus.com>
3148 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3151 Correct me if I'm wrong, folks, but the way I understand it
3152 is this: Using DCACHE as initial RAM for Stack, etc, does not
3153 require any physical RAM backing up the cache. The cleverness
3154 is that the cache is being used as a temporary supply of
3155 necessary storage before the SDRAM controller is setup. It's
3156 beyond the scope of this list to expain the details, but you
3157 can see how this works by studying the cache architecture and
3158 operation in the architecture and processor-specific manuals.
3160 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3161 is another option for the system designer to use as an
3162 initial stack/ram area prior to SDRAM being available. Either
3163 option should work for you. Using CS 4 should be fine if your
3164 board designers haven't used it for something that would
3165 cause you grief during the initial boot! It is frequently not
3168 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3169 with your processor/board/system design. The default value
3170 you will find in any recent u-boot distribution in
3171 walnut.h should work for you. I'd set it to a value larger
3172 than your SDRAM module. If you have a 64MB SDRAM module, set
3173 it above 400_0000. Just make sure your board has no resources
3174 that are supposed to respond to that address! That code in
3175 start.S has been around a while and should work as is when
3176 you get the config right.
3181 It is essential to remember this, since it has some impact on the C
3182 code for the initialization procedures:
3184 * Initialized global data (data segment) is read-only. Do not attempt
3187 * Do not use any unitialized global data (or implicitely initialized
3188 as zero data - BSS segment) at all - this is undefined, initiali-
3189 zation is performed later (when relocating to RAM).
3191 * Stack space is very limited. Avoid big data buffers or things like
3194 Having only the stack as writable memory limits means we cannot use
3195 normal global data to share information beween the code. But it
3196 turned out that the implementation of U-Boot can be greatly
3197 simplified by making a global data structure (gd_t) available to all
3198 functions. We could pass a pointer to this data as argument to _all_
3199 functions, but this would bloat the code. Instead we use a feature of
3200 the GCC compiler (Global Register Variables) to share the data: we
3201 place a pointer (gd) to the global data into a register which we
3202 reserve for this purpose.
3204 When choosing a register for such a purpose we are restricted by the
3205 relevant (E)ABI specifications for the current architecture, and by
3206 GCC's implementation.
3208 For PowerPC, the following registers have specific use:
3211 R3-R4: parameter passing and return values
3212 R5-R10: parameter passing
3213 R13: small data area pointer
3217 (U-Boot also uses R14 as internal GOT pointer.)
3219 ==> U-Boot will use R29 to hold a pointer to the global data
3221 Note: on PPC, we could use a static initializer (since the
3222 address of the global data structure is known at compile time),
3223 but it turned out that reserving a register results in somewhat
3224 smaller code - although the code savings are not that big (on
3225 average for all boards 752 bytes for the whole U-Boot image,
3226 624 text + 127 data).
3228 On ARM, the following registers are used:
3230 R0: function argument word/integer result
3231 R1-R3: function argument word
3233 R10: stack limit (used only if stack checking if enabled)
3234 R11: argument (frame) pointer
3235 R12: temporary workspace
3238 R15: program counter
3240 ==> U-Boot will use R8 to hold a pointer to the global data
3246 U-Boot runs in system state and uses physical addresses, i.e. the
3247 MMU is not used either for address mapping nor for memory protection.
3249 The available memory is mapped to fixed addresses using the memory
3250 controller. In this process, a contiguous block is formed for each
3251 memory type (Flash, SDRAM, SRAM), even when it consists of several
3252 physical memory banks.
3254 U-Boot is installed in the first 128 kB of the first Flash bank (on
3255 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3256 booting and sizing and initializing DRAM, the code relocates itself
3257 to the upper end of DRAM. Immediately below the U-Boot code some
3258 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3259 configuration setting]. Below that, a structure with global Board
3260 Info data is placed, followed by the stack (growing downward).
3262 Additionally, some exception handler code is copied to the low 8 kB
3263 of DRAM (0x00000000 ... 0x00001FFF).
3265 So a typical memory configuration with 16 MB of DRAM could look like
3268 0x0000 0000 Exception Vector code
3271 0x0000 2000 Free for Application Use
3277 0x00FB FF20 Monitor Stack (Growing downward)
3278 0x00FB FFAC Board Info Data and permanent copy of global data
3279 0x00FC 0000 Malloc Arena
3282 0x00FE 0000 RAM Copy of Monitor Code
3283 ... eventually: LCD or video framebuffer
3284 ... eventually: pRAM (Protected RAM - unchanged by reset)
3285 0x00FF FFFF [End of RAM]
3288 System Initialization:
3289 ----------------------
3291 In the reset configuration, U-Boot starts at the reset entry point
3292 (on most PowerPC systens at address 0x00000100). Because of the reset
3293 configuration for CS0# this is a mirror of the onboard Flash memory.
3294 To be able to re-map memory U-Boot then jumps to its link address.
3295 To be able to implement the initialization code in C, a (small!)
3296 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3297 which provide such a feature like MPC8xx or MPC8260), or in a locked
3298 part of the data cache. After that, U-Boot initializes the CPU core,
3299 the caches and the SIU.
3301 Next, all (potentially) available memory banks are mapped using a
3302 preliminary mapping. For example, we put them on 512 MB boundaries
3303 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3304 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3305 programmed for SDRAM access. Using the temporary configuration, a
3306 simple memory test is run that determines the size of the SDRAM
3309 When there is more than one SDRAM bank, and the banks are of
3310 different size, the largest is mapped first. For equal size, the first
3311 bank (CS2#) is mapped first. The first mapping is always for address
3312 0x00000000, with any additional banks following immediately to create
3313 contiguous memory starting from 0.
3315 Then, the monitor installs itself at the upper end of the SDRAM area
3316 and allocates memory for use by malloc() and for the global Board
3317 Info data; also, the exception vector code is copied to the low RAM
3318 pages, and the final stack is set up.
3320 Only after this relocation will you have a "normal" C environment;
3321 until that you are restricted in several ways, mostly because you are
3322 running from ROM, and because the code will have to be relocated to a
3326 U-Boot Porting Guide:
3327 ----------------------
3329 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3333 int main (int argc, char *argv[])
3335 sighandler_t no_more_time;
3337 signal (SIGALRM, no_more_time);
3338 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3340 if (available_money > available_manpower) {
3341 pay consultant to port U-Boot;
3345 Download latest U-Boot source;
3347 Subscribe to u-boot-users mailing list;
3350 email ("Hi, I am new to U-Boot, how do I get started?");
3354 Read the README file in the top level directory;
3355 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3356 Read the source, Luke;
3359 if (available_money > toLocalCurrency ($2500)) {
3362 Add a lot of aggravation and time;
3365 Create your own board support subdirectory;
3367 Create your own board config file;
3371 Add / modify source code;
3375 email ("Hi, I am having problems...");
3377 Send patch file to Wolfgang;
3382 void no_more_time (int sig)
3391 All contributions to U-Boot should conform to the Linux kernel
3392 coding style; see the file "Documentation/CodingStyle" in your Linux
3393 kernel source directory.
3395 Please note that U-Boot is implemented in C (and to some small parts
3396 in Assembler); no C++ is used, so please do not use C++ style
3397 comments (//) in your code.
3399 Please also stick to the following formatting rules:
3400 - remove any trailing white space
3401 - use TAB characters for indentation, not spaces
3402 - make sure NOT to use DOS '\r\n' line feeds
3403 - do not add more than 2 empty lines to source files
3404 - do not add trailing empty lines to source files
3406 Submissions which do not conform to the standards may be returned
3407 with a request to reformat the changes.
3413 Since the number of patches for U-Boot is growing, we need to
3414 establish some rules. Submissions which do not conform to these rules
3415 may be rejected, even when they contain important and valuable stuff.
3417 Patches shall be sent to the u-boot-users mailing list.
3419 When you send a patch, please include the following information with
3422 * For bug fixes: a description of the bug and how your patch fixes
3423 this bug. Please try to include a way of demonstrating that the
3424 patch actually fixes something.
3426 * For new features: a description of the feature and your
3429 * A CHANGELOG entry as plaintext (separate from the patch)
3431 * For major contributions, your entry to the CREDITS file
3433 * When you add support for a new board, don't forget to add this
3434 board to the MAKEALL script, too.
3436 * If your patch adds new configuration options, don't forget to
3437 document these in the README file.
3439 * The patch itself. If you are accessing the CVS repository use "cvs
3440 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3441 version of diff does not support these options, then get the latest
3442 version of GNU diff.
3444 The current directory when running this command shall be the top
3445 level directory of the U-Boot source tree, or it's parent directory
3446 (i. e. please make sure that your patch includes sufficient
3447 directory information for the affected files).
3449 We accept patches as plain text, MIME attachments or as uuencoded
3452 * If one logical set of modifications affects or creates several
3453 files, all these changes shall be submitted in a SINGLE patch file.
3455 * Changesets that contain different, unrelated modifications shall be
3456 submitted as SEPARATE patches, one patch per changeset.
3461 * Before sending the patch, run the MAKEALL script on your patched
3462 source tree and make sure that no errors or warnings are reported
3463 for any of the boards.
3465 * Keep your modifications to the necessary minimum: A patch
3466 containing several unrelated changes or arbitrary reformats will be
3467 returned with a request to re-formatting / split it.
3469 * If you modify existing code, make sure that your new code does not
3470 add to the memory footprint of the code ;-) Small is beautiful!
3471 When adding new features, these should compile conditionally only
3472 (using #ifdef), and the resulting code with the new feature
3473 disabled must not need more memory than the old code without your
3476 * Remember that there is a size limit of 40 kB per message on the
3477 u-boot-users mailing list. Compression may help.