2 # (C) Copyright 2000 - 2004
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 and ARM processors, which can be
29 installed in a boot ROM and used to initialize and test the hardware
30 or to download and run application code.
32 The development of U-Boot is closely related to Linux: some parts of
33 the source code originate in the Linux source tree, we have some
34 header files in common, and special provision has been made to
35 support booting of Linux images.
37 Some attention has been paid to make this software easily
38 configurable and extendable. For instance, all monitor commands are
39 implemented with the same call interface, so that it's very easy to
40 add new commands. Also, instead of permanently adding rarely used
41 code (for instance hardware test utilities) to the monitor, you can
42 load and run it dynamically.
48 In general, all boards for which a configuration option exists in the
49 Makefile have been tested to some extent and can be considered
50 "working". In fact, many of them are used in production systems.
52 In case of problems see the CHANGELOG and CREDITS files to find out
53 who contributed the specific port.
59 In case you have questions about, problems with or contributions for
60 U-Boot you should send a message to the U-Boot mailing list at
61 <u-boot-users@lists.sourceforge.net>. There is also an archive of
62 previous traffic on the mailing list - please search the archive
63 before asking FAQ's. Please see
64 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
70 - start from 8xxrom sources
71 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
73 - make it easier to add custom boards
74 - make it possible to add other [PowerPC] CPUs
75 - extend functions, especially:
76 * Provide extended interface to Linux boot loader
79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
80 - create ARMBoot project (http://sourceforge.net/projects/armboot)
81 - add other CPU families (starting with ARM)
82 - create U-Boot project (http://sourceforge.net/projects/u-boot)
88 The "official" name of this project is "Das U-Boot". The spelling
89 "U-Boot" shall be used in all written text (documentation, comments
90 in source files etc.). Example:
92 This is the README file for the U-Boot project.
94 File names etc. shall be based on the string "u-boot". Examples:
96 include/asm-ppc/u-boot.h
98 #include <asm/u-boot.h>
100 Variable names, preprocessor constants etc. shall be either based on
101 the string "u_boot" or on "U_BOOT". Example:
103 U_BOOT_VERSION u_boot_logo
104 IH_OS_U_BOOT u_boot_hush_start
110 U-Boot uses a 3 level version number containing a version, a
111 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
112 sub-version "34", and patchlevel "4".
114 The patchlevel is used to indicate certain stages of development
115 between released versions, i. e. officially released versions of
116 U-Boot will always have a patchlevel of "0".
122 - board Board dependent files
123 - common Misc architecture independent functions
124 - cpu CPU specific files
125 - 74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs
126 - arm720t Files specific to ARM 720 CPUs
127 - arm920t Files specific to ARM 920 CPUs
128 - arm925t Files specific to ARM 925 CPUs
129 - arm926ejs Files specific to ARM 926 CPUs
130 - at91rm9200 Files specific to Atmel AT91RM9200 CPUs
131 - i386 Files specific to i386 CPUs
132 - ixp Files specific to Intel XScale IXP CPUs
133 - mcf52x2 Files specific to Motorola ColdFire MCF52x2 CPUs
134 - mips Files specific to MIPS CPUs
135 - mpc5xx Files specific to Motorola MPC5xx CPUs
136 - mpc5xxx Files specific to Motorola MPC5xxx CPUs
137 - mpc8xx Files specific to Motorola MPC8xx CPUs
138 - mpc824x Files specific to Motorola MPC824x CPUs
139 - mpc8260 Files specific to Motorola MPC8260 CPUs
140 - mpc85xx Files specific to Motorola MPC85xx CPUs
141 - nios Files specific to Altera NIOS CPUs
142 - ppc4xx Files specific to IBM PowerPC 4xx CPUs
143 - pxa Files specific to Intel XScale PXA CPUs
144 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
145 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
146 - disk Code for disk drive partition handling
147 - doc Documentation (don't expect too much)
148 - drivers Commonly used device drivers
149 - dtt Digital Thermometer and Thermostat drivers
150 - examples Example code for standalone applications, etc.
151 - include Header Files
152 - lib_arm Files generic to ARM architecture
153 - lib_generic Files generic to all architectures
154 - lib_i386 Files generic to i386 architecture
155 - lib_m68k Files generic to m68k architecture
156 - lib_mips Files generic to MIPS architecture
157 - lib_nios Files generic to NIOS architecture
158 - lib_ppc Files generic to PowerPC architecture
159 - net Networking code
160 - post Power On Self Test
161 - rtc Real Time Clock drivers
162 - tools Tools to build S-Record or U-Boot images, etc.
164 Software Configuration:
165 =======================
167 Configuration is usually done using C preprocessor defines; the
168 rationale behind that is to avoid dead code whenever possible.
170 There are two classes of configuration variables:
172 * Configuration _OPTIONS_:
173 These are selectable by the user and have names beginning with
176 * Configuration _SETTINGS_:
177 These depend on the hardware etc. and should not be meddled with if
178 you don't know what you're doing; they have names beginning with
181 Later we will add a configuration tool - probably similar to or even
182 identical to what's used for the Linux kernel. Right now, we have to
183 do the configuration by hand, which means creating some symbolic
184 links and editing some configuration files. We use the TQM8xxL boards
188 Selection of Processor Architecture and Board Type:
189 ---------------------------------------------------
191 For all supported boards there are ready-to-use default
192 configurations available; just type "make <board_name>_config".
194 Example: For a TQM823L module type:
199 For the Cogent platform, you need to specify the cpu type as well;
200 e.g. "make cogent_mpc8xx_config". And also configure the cogent
201 directory according to the instructions in cogent/README.
204 Configuration Options:
205 ----------------------
207 Configuration depends on the combination of board and CPU type; all
208 such information is kept in a configuration file
209 "include/configs/<board_name>.h".
211 Example: For a TQM823L module, all configuration settings are in
212 "include/configs/TQM823L.h".
215 Many of the options are named exactly as the corresponding Linux
216 kernel configuration options. The intention is to make it easier to
217 build a config tool - later.
220 The following options need to be configured:
222 - CPU Type: Define exactly one of
226 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
228 or CONFIG_MPC824X, CONFIG_MPC8260
243 MicroBlaze based CPUs:
244 ----------------------
248 - Board Type: Define exactly one of
250 PowerPC based boards:
251 ---------------------
253 CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCI405
254 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC2
255 CONFIG_AMX860 CONFIG_GTH CONFIG_PCIPPC6
256 CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e
257 CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405
258 CONFIG_c2mon CONFIG_hymod CONFIG_PM826
259 CONFIG_CANBT CONFIG_IAD210 CONFIG_ppmc8260
260 CONFIG_CCM CONFIG_ICU862 CONFIG_QS823
261 CONFIG_CMI CONFIG_IP860 CONFIG_QS850
262 CONFIG_cogent_mpc8260 CONFIG_IPHASE4539 CONFIG_QS860T
263 CONFIG_cogent_mpc8xx CONFIG_IVML24 CONFIG_RBC823
264 CONFIG_CPCI405 CONFIG_IVML24_128 CONFIG_RPXClassic
265 CONFIG_CPCI4052 CONFIG_IVML24_256 CONFIG_RPXlite
266 CONFIG_CPCIISER4 CONFIG_IVMS8 CONFIG_RPXsuper
267 CONFIG_CPU86 CONFIG_IVMS8_128 CONFIG_rsdproto
268 CONFIG_CRAYL1 CONFIG_IVMS8_256 CONFIG_sacsng
269 CONFIG_CSB272 CONFIG_JSE CONFIG_Sandpoint8240
270 CONFIG_CU824 CONFIG_LANTEC CONFIG_Sandpoint8245
271 CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8260
272 CONFIG_DB64360 CONFIG_MBX CONFIG_SM850
273 CONFIG_DB64460 CONFIG_MBX860T CONFIG_SPD823TS
274 CONFIG_DU405 CONFIG_MHPC CONFIG_STXGP3
275 CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_SXNI855T
276 CONFIG_EBONY CONFIG_MOUSSE CONFIG_TQM823L
277 CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM8260
278 CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM850L
279 CONFIG_ep8260 CONFIG_MPC8560ADS CONFIG_TQM855L
280 CONFIG_ERIC CONFIG_MUSENKI CONFIG_TQM860L
281 CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_TTTech
282 CONFIG_ETX094 CONFIG_NETPHONE CONFIG_UTX8245
283 CONFIG_EVB64260 CONFIG_NETTA CONFIG_V37
284 CONFIG_FADS823 CONFIG_NETVIA CONFIG_W7OLMC
285 CONFIG_FADS850SAR CONFIG_NX823 CONFIG_W7OLMG
286 CONFIG_FADS860T CONFIG_OCRTC CONFIG_WALNUT405
287 CONFIG_FLAGADM CONFIG_ORSG CONFIG_ZPC1900
288 CONFIG_FPS850L CONFIG_OXC CONFIG_ZUMA
294 CONFIG_AT91RM9200DK, CONFIG_DNP1110, CONFIG_EP7312,
295 CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE, CONFIG_IMPA7,
296 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, CONFIG_LART,
297 CONFIG_LPD7A400 CONFIG_LUBBOCK, CONFIG_OSK_OMAP5912,
298 CONFIG_SHANNON, CONFIG_P2_OMAP730, CONFIG_SMDK2400,
299 CONFIG_SMDK2410, CONFIG_TRAB, CONFIG_VCMA9
301 MicroBlaze based boards:
302 ------------------------
307 - CPU Module Type: (if CONFIG_COGENT is defined)
308 Define exactly one of
310 --- FIXME --- not tested yet:
311 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
312 CONFIG_CMA287_23, CONFIG_CMA287_50
314 - Motherboard Type: (if CONFIG_COGENT is defined)
315 Define exactly one of
316 CONFIG_CMA101, CONFIG_CMA102
318 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
319 Define one or more of
322 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
323 Define one or more of
324 CONFIG_LCD_HEARTBEAT - update a character position on
325 the lcd display every second with
328 - Board flavour: (if CONFIG_MPC8260ADS is defined)
331 CFG_8260ADS - original MPC8260ADS
332 CFG_8266ADS - MPC8266ADS
333 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
334 CFG_8272ADS - MPC8272ADS
336 - MPC824X Family Member (if CONFIG_MPC824X is defined)
337 Define exactly one of
338 CONFIG_MPC8240, CONFIG_MPC8245
340 - 8xx CPU Options: (if using an MPC8xx cpu)
341 Define one or more of
342 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work
343 e.g. if there is no 32KHz
344 reference PIT/RTC clock
346 - 859/866 CPU options: (if using a MPC859 or MPC866 CPU):
350 CFG_866_CPUCLK_DEFAULT
351 See doc/README.MPC866
355 Define this to measure the actual CPU clock instead
356 of relying on the correctness of the configured
357 values. Mostly useful for board bringup to make sure
358 the PLL is locked at the intended frequency. Note
359 that this requires a (stable) reference clock (32 kHz
362 - Linux Kernel Interface:
365 U-Boot stores all clock information in Hz
366 internally. For binary compatibility with older Linux
367 kernels (which expect the clocks passed in the
368 bd_info data to be in MHz) the environment variable
369 "clocks_in_mhz" can be defined so that U-Boot
370 converts clock data to MHZ before passing it to the
372 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
373 "clocks_in_mhz=1" is automatically included in the
376 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
378 When transfering memsize parameter to linux, some versions
379 expect it to be in bytes, others in MB.
380 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
383 Depending on board, define exactly one serial port
384 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
385 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
386 console by defining CONFIG_8xx_CONS_NONE
388 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
389 port routines must be defined elsewhere
390 (i.e. serial_init(), serial_getc(), ...)
393 Enables console device for a color framebuffer. Needs following
394 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
395 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
397 VIDEO_HW_RECTFILL graphic chip supports
400 VIDEO_HW_BITBLT graphic chip supports
401 bit-blit (cf. smiLynxEM)
402 VIDEO_VISIBLE_COLS visible pixel columns
404 VIDEO_VISIBLE_ROWS visible pixel rows
405 VIDEO_PIXEL_SIZE bytes per pixel
406 VIDEO_DATA_FORMAT graphic data format
407 (0-5, cf. cfb_console.c)
408 VIDEO_FB_ADRS framebuffer address
409 VIDEO_KBD_INIT_FCT keyboard int fct
410 (i.e. i8042_kbd_init())
411 VIDEO_TSTC_FCT test char fct
413 VIDEO_GETC_FCT get char fct
415 CONFIG_CONSOLE_CURSOR cursor drawing on/off
416 (requires blink timer
418 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
419 CONFIG_CONSOLE_TIME display time/date info in
421 (requires CFG_CMD_DATE)
422 CONFIG_VIDEO_LOGO display Linux logo in
424 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
425 linux_logo.h for logo.
426 Requires CONFIG_VIDEO_LOGO
427 CONFIG_CONSOLE_EXTRA_INFO
428 addional board info beside
431 When CONFIG_CFB_CONSOLE is defined, video console is
432 default i/o. Serial console can be forced with
433 environment 'console=serial'.
435 When CONFIG_SILENT_CONSOLE is defined, all console
436 messages (by U-Boot and Linux!) can be silenced with
437 the "silent" environment variable. See
438 doc/README.silent for more information.
441 CONFIG_BAUDRATE - in bps
442 Select one of the baudrates listed in
443 CFG_BAUDRATE_TABLE, see below.
444 CFG_BRGCLK_PRESCALE, baudrate prescale
446 - Interrupt driven serial port input:
447 CONFIG_SERIAL_SOFTWARE_FIFO
450 Use an interrupt handler for receiving data on the
451 serial port. It also enables using hardware handshake
452 (RTS/CTS) and UART's built-in FIFO. Set the number of
453 bytes the interrupt driven input buffer should have.
455 Leave undefined to disable this feature, including
456 disable the buffer and hardware handshake.
458 - Console UART Number:
462 If defined internal UART1 (and not UART0) is used
463 as default U-Boot console.
465 - Boot Delay: CONFIG_BOOTDELAY - in seconds
466 Delay before automatically booting the default image;
467 set to -1 to disable autoboot.
469 See doc/README.autoboot for these options that
470 work with CONFIG_BOOTDELAY. None are required.
471 CONFIG_BOOT_RETRY_TIME
472 CONFIG_BOOT_RETRY_MIN
473 CONFIG_AUTOBOOT_KEYED
474 CONFIG_AUTOBOOT_PROMPT
475 CONFIG_AUTOBOOT_DELAY_STR
476 CONFIG_AUTOBOOT_STOP_STR
477 CONFIG_AUTOBOOT_DELAY_STR2
478 CONFIG_AUTOBOOT_STOP_STR2
479 CONFIG_ZERO_BOOTDELAY_CHECK
480 CONFIG_RESET_TO_RETRY
484 Only needed when CONFIG_BOOTDELAY is enabled;
485 define a command string that is automatically executed
486 when no character is read on the console interface
487 within "Boot Delay" after reset.
490 This can be used to pass arguments to the bootm
491 command. The value of CONFIG_BOOTARGS goes into the
492 environment value "bootargs".
494 CONFIG_RAMBOOT and CONFIG_NFSBOOT
495 The value of these goes into the environment as
496 "ramboot" and "nfsboot" respectively, and can be used
497 as a convenience, when switching between booting from
503 When this option is #defined, the existence of the
504 environment variable "preboot" will be checked
505 immediately before starting the CONFIG_BOOTDELAY
506 countdown and/or running the auto-boot command resp.
507 entering interactive mode.
509 This feature is especially useful when "preboot" is
510 automatically generated or modified. For an example
511 see the LWMON board specific code: here "preboot" is
512 modified when the user holds down a certain
513 combination of keys on the (special) keyboard when
516 - Serial Download Echo Mode:
518 If defined to 1, all characters received during a
519 serial download (using the "loads" command) are
520 echoed back. This might be needed by some terminal
521 emulations (like "cu"), but may as well just take
522 time on others. This setting #define's the initial
523 value of the "loads_echo" environment variable.
525 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
527 Select one of the baudrates listed in
528 CFG_BAUDRATE_TABLE, see below.
532 Most monitor functions can be selected (or
533 de-selected) by adjusting the definition of
534 CONFIG_COMMANDS; to select individual functions,
535 #define CONFIG_COMMANDS by "OR"ing any of the
538 #define enables commands:
539 -------------------------
540 CFG_CMD_ASKENV * ask for env variable
541 CFG_CMD_AUTOSCRIPT Autoscript Support
543 CFG_CMD_BEDBUG Include BedBug Debugger
544 CFG_CMD_BMP * BMP support
546 CFG_CMD_CACHE icache, dcache
547 CFG_CMD_CONSOLE coninfo
548 CFG_CMD_DATE * support for RTC, date/time...
549 CFG_CMD_DHCP DHCP support
550 CFG_CMD_DIAG * Diagnostics
551 CFG_CMD_DOC * Disk-On-Chip Support
552 CFG_CMD_DTT Digital Therm and Thermostat
553 CFG_CMD_ECHO * echo arguments
554 CFG_CMD_EEPROM * EEPROM read/write support
555 CFG_CMD_ELF bootelf, bootvx
557 CFG_CMD_FDC * Floppy Disk Support
558 CFG_CMD_FAT FAT partition support
559 CFG_CMD_FDOS * Dos diskette Support
560 CFG_CMD_FLASH flinfo, erase, protect
561 CFG_CMD_FPGA FPGA device initialization support
562 CFG_CMD_HWFLOW * RTS/CTS hw flow control
563 CFG_CMD_I2C * I2C serial bus support
564 CFG_CMD_IDE * IDE harddisk support
566 CFG_CMD_IMLS List all found images
567 CFG_CMD_IMMAP * IMMR dump support
568 CFG_CMD_IRQ * irqinfo
569 CFG_CMD_ITEST * Integer/string test of 2 values
570 CFG_CMD_JFFS2 * JFFS2 Support
574 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
576 CFG_CMD_MISC Misc functions like sleep etc
577 CFG_CMD_MMC MMC memory mapped support
578 CFG_CMD_MII MII utility commands
579 CFG_CMD_NAND * NAND support
580 CFG_CMD_NET bootp, tftpboot, rarpboot
581 CFG_CMD_PCI * pciinfo
582 CFG_CMD_PCMCIA * PCMCIA support
583 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
584 CFG_CMD_PORTIO * Port I/O
585 CFG_CMD_REGINFO * Register dump
586 CFG_CMD_RUN run command in env variable
587 CFG_CMD_SAVES save S record dump
588 CFG_CMD_SCSI * SCSI Support
589 CFG_CMD_SDRAM * print SDRAM configuration information
590 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
591 CFG_CMD_SPI * SPI serial bus support
592 CFG_CMD_USB * USB support
593 CFG_CMD_VFD * VFD support (TRAB)
594 CFG_CMD_BSP * Board SPecific functions
595 CFG_CMD_CDP * Cisco Discover Protocol support
596 -----------------------------------------------
599 CFG_CMD_DFL Default configuration; at the moment
600 this is includes all commands, except
601 the ones marked with "*" in the list
604 If you don't define CONFIG_COMMANDS it defaults to
605 CFG_CMD_DFL in include/cmd_confdefs.h. A board can
606 override the default settings in the respective
609 EXAMPLE: If you want all functions except of network
610 support you can write:
612 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
615 Note: Don't enable the "icache" and "dcache" commands
616 (configuration option CFG_CMD_CACHE) unless you know
617 what you (and your U-Boot users) are doing. Data
618 cache cannot be enabled on systems like the 8xx or
619 8260 (where accesses to the IMMR region must be
620 uncached), and it cannot be disabled on all other
621 systems where we (mis-) use the data cache to hold an
622 initial stack and some data.
625 XXX - this list needs to get updated!
629 If this variable is defined, it enables watchdog
630 support. There must be support in the platform specific
631 code for a watchdog. For the 8xx and 8260 CPUs, the
632 SIU Watchdog feature is enabled in the SYPCR
636 CONFIG_VERSION_VARIABLE
637 If this variable is defined, an environment variable
638 named "ver" is created by U-Boot showing the U-Boot
639 version as printed by the "version" command.
640 This variable is readonly.
644 When CFG_CMD_DATE is selected, the type of the RTC
645 has to be selected, too. Define exactly one of the
648 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
649 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
650 CONFIG_RTC_MC146818 - use MC146818 RTC
651 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
652 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
653 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
654 CONFIG_RTC_DS164x - use Dallas DS164x RTC
656 Note that if the RTC uses I2C, then the I2C interface
657 must also be configured. See I2C Support, below.
661 When CONFIG_TIMESTAMP is selected, the timestamp
662 (date and time) of an image is printed by image
663 commands like bootm or iminfo. This option is
664 automatically enabled when you select CFG_CMD_DATE .
667 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
668 and/or CONFIG_ISO_PARTITION
670 If IDE or SCSI support is enabled (CFG_CMD_IDE or
671 CFG_CMD_SCSI) you must configure support for at least
672 one partition type as well.
675 CONFIG_IDE_RESET_ROUTINE - this is defined in several
676 board configurations files but used nowhere!
678 CONFIG_IDE_RESET - is this is defined, IDE Reset will
679 be performed by calling the function
680 ide_set_reset(int reset)
681 which has to be defined in a board specific file
686 Set this to enable ATAPI support.
691 Set this to enable support for disks larger than 137GB
692 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
693 Whithout these , LBA48 support uses 32bit variables and will 'only'
694 support disks up to 2.1TB.
697 When enabled, makes the IDE subsystem use 64bit sector addresses.
701 At the moment only there is only support for the
702 SYM53C8XX SCSI controller; define
703 CONFIG_SCSI_SYM53C8XX to enable it.
705 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
706 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
707 CFG_SCSI_MAX_LUN] can be adjusted to define the
708 maximum numbers of LUNs, SCSI ID's and target
710 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
712 - NETWORK Support (PCI):
714 Support for Intel 8254x gigabit chips.
717 Support for Intel 82557/82559/82559ER chips.
718 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
719 write routine for first time initialisation.
722 Support for Digital 2114x chips.
723 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
724 modem chip initialisation (KS8761/QS6611).
727 Support for National dp83815 chips.
730 Support for National dp8382[01] gigabit chips.
732 - NETWORK Support (other):
734 CONFIG_DRIVER_LAN91C96
735 Support for SMSC's LAN91C96 chips.
738 Define this to hold the physical address
739 of the LAN91C96's I/O space
741 CONFIG_LAN91C96_USE_32_BIT
742 Define this to enable 32 bit addressing
744 CONFIG_DRIVER_SMC91111
745 Support for SMSC's LAN91C111 chip
748 Define this to hold the physical address
749 of the device (I/O space)
751 CONFIG_SMC_USE_32_BIT
752 Define this if data bus is 32 bits
754 CONFIG_SMC_USE_IOFUNCS
755 Define this to use i/o functions instead of macros
756 (some hardware wont work with macros)
759 At the moment only the UHCI host controller is
760 supported (PIP405, MIP405, MPC5200); define
761 CONFIG_USB_UHCI to enable it.
762 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
763 end define CONFIG_USB_STORAGE to enable the USB
766 Supported are USB Keyboards and USB Floppy drives
768 MPC5200 USB requires additional defines:
770 for 528 MHz Clock: 0x0001bbbb
772 for differential drivers: 0x00001000
773 for single ended drivers: 0x00005000
777 The MMC controller on the Intel PXA is supported. To
778 enable this define CONFIG_MMC. The MMC can be
779 accessed from the boot prompt by mapping the device
780 to physical memory similar to flash. Command line is
781 enabled with CFG_CMD_MMC. The MMC driver also works with
782 the FAT fs. This is enabled with CFG_CMD_FAT.
787 Define this to enable standard (PC-Style) keyboard
791 Standard PC keyboard driver with US (is default) and
792 GERMAN key layout (switch via environment 'keymap=de') support.
793 Export function i8042_kbd_init, i8042_tstc and i8042_getc
794 for cfb_console. Supports cursor blinking.
799 Define this to enable video support (for output to
804 Enable Chips & Technologies 69000 Video chip
806 CONFIG_VIDEO_SMI_LYNXEM
807 Enable Silicon Motion SMI 712/710/810 Video chip. The
808 video output is selected via environment 'videoout'
809 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
812 For the CT69000 and SMI_LYNXEM drivers, videomode is
813 selected via environment 'videomode'. Two diferent ways
815 - "videomode=num" 'num' is a standard LiLo mode numbers.
816 Following standard modes are supported (* is default):
818 Colors 640x480 800x600 1024x768 1152x864 1280x1024
819 -------------+---------------------------------------------
820 8 bits | 0x301* 0x303 0x305 0x161 0x307
821 15 bits | 0x310 0x313 0x316 0x162 0x319
822 16 bits | 0x311 0x314 0x317 0x163 0x31A
823 24 bits | 0x312 0x315 0x318 ? 0x31B
824 -------------+---------------------------------------------
825 (i.e. setenv videomode 317; saveenv; reset;)
827 - "videomode=bootargs" all the video parameters are parsed
828 from the bootargs. (See drivers/videomodes.c)
831 CONFIG_VIDEO_SED13806
832 Enable Epson SED13806 driver. This driver supports 8bpp
833 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
834 or CONFIG_VIDEO_SED13806_16BPP
839 Define this to enable a custom keyboard support.
840 This simply calls drv_keyboard_init() which must be
841 defined in your board-specific files.
842 The only board using this so far is RBC823.
844 - LCD Support: CONFIG_LCD
846 Define this to enable LCD support (for output to LCD
847 display); also select one of the supported displays
848 by defining one of these:
850 CONFIG_NEC_NL6448AC33:
852 NEC NL6448AC33-18. Active, color, single scan.
854 CONFIG_NEC_NL6448BC20
856 NEC NL6448BC20-08. 6.5", 640x480.
857 Active, color, single scan.
859 CONFIG_NEC_NL6448BC33_54
861 NEC NL6448BC33-54. 10.4", 640x480.
862 Active, color, single scan.
866 Sharp 320x240. Active, color, single scan.
867 It isn't 16x9, and I am not sure what it is.
869 CONFIG_SHARP_LQ64D341
871 Sharp LQ64D341 display, 640x480.
872 Active, color, single scan.
876 HLD1045 display, 640x480.
877 Active, color, single scan.
881 Optrex CBL50840-2 NF-FW 99 22 M5
883 Hitachi LMG6912RPFC-00T
887 320x240. Black & white.
889 Normally display is black on white background; define
890 CFG_WHITE_ON_BLACK to get it inverted.
892 - Splash Screen Support: CONFIG_SPLASH_SCREEN
894 If this option is set, the environment is checked for
895 a variable "splashimage". If found, the usual display
896 of logo, copyright and system information on the LCD
897 is supressed and the BMP image at the address
898 specified in "splashimage" is loaded instead. The
899 console is redirected to the "nulldev", too. This
900 allows for a "silent" boot where a splash screen is
901 loaded very quickly after power-on.
903 - Compression support:
906 If this option is set, support for bzip2 compressed
907 images is included. If not, only uncompressed and gzip
908 compressed images are supported.
910 NOTE: the bzip2 algorithm requires a lot of RAM, so
911 the malloc area (as defined by CFG_MALLOC_LEN) should
917 The address of PHY on MII bus.
919 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
921 The clock frequency of the MII bus
925 If this option is set, support for speed/duplex
926 detection of Gigabit PHY is included.
928 CONFIG_PHY_RESET_DELAY
930 Some PHY like Intel LXT971A need extra delay after
931 reset before any MII register access is possible.
932 For such PHY, set this option to the usec delay
933 required. (minimum 300usec for LXT971A)
935 CONFIG_PHY_CMD_DELAY (ppc4xx)
937 Some PHY like Intel LXT971A need extra delay after
938 command issued before MII status register can be read
945 Define a default value for ethernet address to use
946 for the respective ethernet interface, in case this
947 is not determined automatically.
952 Define a default value for the IP address to use for
953 the default ethernet interface, in case this is not
954 determined through e.g. bootp.
959 Defines a default value for theIP address of a TFTP
960 server to contact when using the "tftboot" command.
962 - BOOTP Recovery Mode:
963 CONFIG_BOOTP_RANDOM_DELAY
965 If you have many targets in a network that try to
966 boot using BOOTP, you may want to avoid that all
967 systems send out BOOTP requests at precisely the same
968 moment (which would happen for instance at recovery
969 from a power failure, when all systems will try to
970 boot, thus flooding the BOOTP server. Defining
971 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
972 inserted before sending out BOOTP requests. The
973 following delays are insterted then:
975 1st BOOTP request: delay 0 ... 1 sec
976 2nd BOOTP request: delay 0 ... 2 sec
977 3rd BOOTP request: delay 0 ... 4 sec
979 BOOTP requests: delay 0 ... 8 sec
981 - DHCP Advanced Options:
984 You can fine tune the DHCP functionality by adding
985 these flags to the CONFIG_BOOTP_MASK define:
987 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
988 serverip from a DHCP server, it is possible that more
989 than one DNS serverip is offered to the client.
990 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
991 serverip will be stored in the additional environment
992 variable "dnsip2". The first DNS serverip is always
993 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
994 is added to the CONFIG_BOOTP_MASK.
996 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
997 to do a dynamic update of a DNS server. To do this, they
998 need the hostname of the DHCP requester.
999 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1000 CONFIG_BOOTP_MASK, the content of the "hostname"
1001 environment variable is passed as option 12 to
1005 CONFIG_CDP_DEVICE_ID
1007 The device id used in CDP trigger frames.
1009 CONFIG_CDP_DEVICE_ID_PREFIX
1011 A two character string which is prefixed to the MAC address
1016 A printf format string which contains the ascii name of
1017 the port. Normally is set to "eth%d" which sets
1018 eth0 for the first ethernet, eth1 for the second etc.
1020 CONFIG_CDP_CAPABILITIES
1022 A 32bit integer which indicates the device capabilities;
1023 0x00000010 for a normal host which does not forwards.
1027 An ascii string containing the version of the software.
1031 An ascii string containing the name of the platform.
1035 A 32bit integer sent on the trigger.
1037 CONFIG_CDP_POWER_CONSUMPTION
1039 A 16bit integer containing the power consumption of the
1040 device in .1 of milliwatts.
1042 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1044 A byte containing the id of the VLAN.
1046 - Status LED: CONFIG_STATUS_LED
1048 Several configurations allow to display the current
1049 status using a LED. For instance, the LED will blink
1050 fast while running U-Boot code, stop blinking as
1051 soon as a reply to a BOOTP request was received, and
1052 start blinking slow once the Linux kernel is running
1053 (supported by a status LED driver in the Linux
1054 kernel). Defining CONFIG_STATUS_LED enables this
1057 - CAN Support: CONFIG_CAN_DRIVER
1059 Defining CONFIG_CAN_DRIVER enables CAN driver support
1060 on those systems that support this (optional)
1061 feature, like the TQM8xxL modules.
1063 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1065 These enable I2C serial bus commands. Defining either of
1066 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1067 include the appropriate I2C driver for the selected cpu.
1069 This will allow you to use i2c commands at the u-boot
1070 command line (as long as you set CFG_CMD_I2C in
1071 CONFIG_COMMANDS) and communicate with i2c based realtime
1072 clock chips. See common/cmd_i2c.c for a description of the
1073 command line interface.
1075 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1077 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1078 bit-banging) driver instead of CPM or similar hardware
1081 There are several other quantities that must also be
1082 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1084 In both cases you will need to define CFG_I2C_SPEED
1085 to be the frequency (in Hz) at which you wish your i2c bus
1086 to run and CFG_I2C_SLAVE to be the address of this node (ie
1087 the cpu's i2c node address).
1089 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1090 sets the cpu up as a master node and so its address should
1091 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1092 p.16-473). So, set CFG_I2C_SLAVE to 0.
1094 That's all that's required for CONFIG_HARD_I2C.
1096 If you use the software i2c interface (CONFIG_SOFT_I2C)
1097 then the following macros need to be defined (examples are
1098 from include/configs/lwmon.h):
1102 (Optional). Any commands necessary to enable the I2C
1103 controller or configure ports.
1105 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1109 (Only for MPC8260 CPU). The I/O port to use (the code
1110 assumes both bits are on the same port). Valid values
1111 are 0..3 for ports A..D.
1115 The code necessary to make the I2C data line active
1116 (driven). If the data line is open collector, this
1119 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1123 The code necessary to make the I2C data line tri-stated
1124 (inactive). If the data line is open collector, this
1127 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1131 Code that returns TRUE if the I2C data line is high,
1134 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1138 If <bit> is TRUE, sets the I2C data line high. If it
1139 is FALSE, it clears it (low).
1141 eg: #define I2C_SDA(bit) \
1142 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1143 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1147 If <bit> is TRUE, sets the I2C clock line high. If it
1148 is FALSE, it clears it (low).
1150 eg: #define I2C_SCL(bit) \
1151 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1152 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1156 This delay is invoked four times per clock cycle so this
1157 controls the rate of data transfer. The data rate thus
1158 is 1 / (I2C_DELAY * 4). Often defined to be something
1161 #define I2C_DELAY udelay(2)
1165 When a board is reset during an i2c bus transfer
1166 chips might think that the current transfer is still
1167 in progress. On some boards it is possible to access
1168 the i2c SCLK line directly, either by using the
1169 processor pin as a GPIO or by having a second pin
1170 connected to the bus. If this option is defined a
1171 custom i2c_init_board() routine in boards/xxx/board.c
1172 is run early in the boot sequence.
1174 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1176 This option enables configuration of bi_iic_fast[] flags
1177 in u-boot bd_info structure based on u-boot environment
1178 variable "i2cfast". (see also i2cfast)
1180 - SPI Support: CONFIG_SPI
1182 Enables SPI driver (so far only tested with
1183 SPI EEPROM, also an instance works with Crystal A/D and
1184 D/As on the SACSng board)
1188 Enables extended (16-bit) SPI EEPROM addressing.
1189 (symmetrical to CONFIG_I2C_X)
1193 Enables a software (bit-bang) SPI driver rather than
1194 using hardware support. This is a general purpose
1195 driver that only requires three general I/O port pins
1196 (two outputs, one input) to function. If this is
1197 defined, the board configuration must define several
1198 SPI configuration items (port pins to use, etc). For
1199 an example, see include/configs/sacsng.h.
1201 - FPGA Support: CONFIG_FPGA_COUNT
1203 Specify the number of FPGA devices to support.
1207 Used to specify the types of FPGA devices. For example,
1208 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1210 CFG_FPGA_PROG_FEEDBACK
1212 Enable printing of hash marks during FPGA configuration.
1216 Enable checks on FPGA configuration interface busy
1217 status by the configuration function. This option
1218 will require a board or device specific function to
1223 If defined, a function that provides delays in the FPGA
1224 configuration driver.
1226 CFG_FPGA_CHECK_CTRLC
1227 Allow Control-C to interrupt FPGA configuration
1229 CFG_FPGA_CHECK_ERROR
1231 Check for configuration errors during FPGA bitfile
1232 loading. For example, abort during Virtex II
1233 configuration if the INIT_B line goes low (which
1234 indicated a CRC error).
1238 Maximum time to wait for the INIT_B line to deassert
1239 after PROB_B has been deasserted during a Virtex II
1240 FPGA configuration sequence. The default time is 500
1245 Maximum time to wait for BUSY to deassert during
1246 Virtex II FPGA configuration. The default is 5 mS.
1248 CFG_FPGA_WAIT_CONFIG
1250 Time to wait after FPGA configuration. The default is
1253 - Configuration Management:
1256 If defined, this string will be added to the U-Boot
1257 version information (U_BOOT_VERSION)
1259 - Vendor Parameter Protection:
1261 U-Boot considers the values of the environment
1262 variables "serial#" (Board Serial Number) and
1263 "ethaddr" (Ethernet Address) to be parameters that
1264 are set once by the board vendor / manufacturer, and
1265 protects these variables from casual modification by
1266 the user. Once set, these variables are read-only,
1267 and write or delete attempts are rejected. You can
1268 change this behviour:
1270 If CONFIG_ENV_OVERWRITE is #defined in your config
1271 file, the write protection for vendor parameters is
1272 completely disabled. Anybody can change or delete
1275 Alternatively, if you #define _both_ CONFIG_ETHADDR
1276 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1277 ethernet address is installed in the environment,
1278 which can be changed exactly ONCE by the user. [The
1279 serial# is unaffected by this, i. e. it remains
1285 Define this variable to enable the reservation of
1286 "protected RAM", i. e. RAM which is not overwritten
1287 by U-Boot. Define CONFIG_PRAM to hold the number of
1288 kB you want to reserve for pRAM. You can overwrite
1289 this default value by defining an environment
1290 variable "pram" to the number of kB you want to
1291 reserve. Note that the board info structure will
1292 still show the full amount of RAM. If pRAM is
1293 reserved, a new environment variable "mem" will
1294 automatically be defined to hold the amount of
1295 remaining RAM in a form that can be passed as boot
1296 argument to Linux, for instance like that:
1298 setenv bootargs ... mem=\$(mem)
1301 This way you can tell Linux not to use this memory,
1302 either, which results in a memory region that will
1303 not be affected by reboots.
1305 *WARNING* If your board configuration uses automatic
1306 detection of the RAM size, you must make sure that
1307 this memory test is non-destructive. So far, the
1308 following board configurations are known to be
1311 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1312 HERMES, IP860, RPXlite, LWMON, LANTEC,
1313 PCU_E, FLAGADM, TQM8260
1318 Define this variable to stop the system in case of a
1319 fatal error, so that you have to reset it manually.
1320 This is probably NOT a good idea for an embedded
1321 system where you want to system to reboot
1322 automatically as fast as possible, but it may be
1323 useful during development since you can try to debug
1324 the conditions that lead to the situation.
1326 CONFIG_NET_RETRY_COUNT
1328 This variable defines the number of retries for
1329 network operations like ARP, RARP, TFTP, or BOOTP
1330 before giving up the operation. If not defined, a
1331 default value of 5 is used.
1333 - Command Interpreter:
1336 Enable auto completion of commands using TAB.
1340 Define this variable to enable the "hush" shell (from
1341 Busybox) as command line interpreter, thus enabling
1342 powerful command line syntax like
1343 if...then...else...fi conditionals or `&&' and '||'
1344 constructs ("shell scripts").
1346 If undefined, you get the old, much simpler behaviour
1347 with a somewhat smaller memory footprint.
1352 This defines the secondary prompt string, which is
1353 printed when the command interpreter needs more input
1354 to complete a command. Usually "> ".
1358 In the current implementation, the local variables
1359 space and global environment variables space are
1360 separated. Local variables are those you define by
1361 simply typing `name=value'. To access a local
1362 variable later on, you have write `$name' or
1363 `${name}'; to execute the contents of a variable
1364 directly type `$name' at the command prompt.
1366 Global environment variables are those you use
1367 setenv/printenv to work with. To run a command stored
1368 in such a variable, you need to use the run command,
1369 and you must not use the '$' sign to access them.
1371 To store commands and special characters in a
1372 variable, please use double quotation marks
1373 surrounding the whole text of the variable, instead
1374 of the backslashes before semicolons and special
1377 - Default Environment:
1378 CONFIG_EXTRA_ENV_SETTINGS
1380 Define this to contain any number of null terminated
1381 strings (variable = value pairs) that will be part of
1382 the default environment compiled into the boot image.
1384 For example, place something like this in your
1385 board's config file:
1387 #define CONFIG_EXTRA_ENV_SETTINGS \
1391 Warning: This method is based on knowledge about the
1392 internal format how the environment is stored by the
1393 U-Boot code. This is NOT an official, exported
1394 interface! Although it is unlikely that this format
1395 will change soon, there is no guarantee either.
1396 You better know what you are doing here.
1398 Note: overly (ab)use of the default environment is
1399 discouraged. Make sure to check other ways to preset
1400 the environment like the autoscript function or the
1403 - DataFlash Support:
1404 CONFIG_HAS_DATAFLASH
1406 Defining this option enables DataFlash features and
1407 allows to read/write in Dataflash via the standard
1410 - SystemACE Support:
1413 Adding this option adds support for Xilinx SystemACE
1414 chips attached via some sort of local bus. The address
1415 of the chip must alsh be defined in the
1416 CFG_SYSTEMACE_BASE macro. For example:
1418 #define CONFIG_SYSTEMACE
1419 #define CFG_SYSTEMACE_BASE 0xf0000000
1421 When SystemACE support is added, the "ace" device type
1422 becomes available to the fat commands, i.e. fatls.
1424 - Show boot progress:
1425 CONFIG_SHOW_BOOT_PROGRESS
1427 Defining this option allows to add some board-
1428 specific code (calling a user-provided function
1429 "show_boot_progress(int)") that enables you to show
1430 the system's boot progress on some display (for
1431 example, some LED's) on your board. At the moment,
1432 the following checkpoints are implemented:
1435 1 common/cmd_bootm.c before attempting to boot an image
1436 -1 common/cmd_bootm.c Image header has bad magic number
1437 2 common/cmd_bootm.c Image header has correct magic number
1438 -2 common/cmd_bootm.c Image header has bad checksum
1439 3 common/cmd_bootm.c Image header has correct checksum
1440 -3 common/cmd_bootm.c Image data has bad checksum
1441 4 common/cmd_bootm.c Image data has correct checksum
1442 -4 common/cmd_bootm.c Image is for unsupported architecture
1443 5 common/cmd_bootm.c Architecture check OK
1444 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1445 6 common/cmd_bootm.c Image Type check OK
1446 -6 common/cmd_bootm.c gunzip uncompression error
1447 -7 common/cmd_bootm.c Unimplemented compression type
1448 7 common/cmd_bootm.c Uncompression OK
1449 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1450 8 common/cmd_bootm.c Image Type check OK
1451 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1452 9 common/cmd_bootm.c Start initial ramdisk verification
1453 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1454 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1455 10 common/cmd_bootm.c Ramdisk header is OK
1456 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1457 11 common/cmd_bootm.c Ramdisk data has correct checksum
1458 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1459 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1460 13 common/cmd_bootm.c Start multifile image verification
1461 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1462 15 common/cmd_bootm.c All preparation done, transferring control to OS
1464 -30 lib_ppc/board.c Fatal error, hang the system
1465 -31 post/post.c POST test failed, detected by post_output_backlog()
1466 -32 post/post.c POST test failed, detected by post_run_single()
1468 -1 common/cmd_doc.c Bad usage of "doc" command
1469 -1 common/cmd_doc.c No boot device
1470 -1 common/cmd_doc.c Unknown Chip ID on boot device
1471 -1 common/cmd_doc.c Read Error on boot device
1472 -1 common/cmd_doc.c Image header has bad magic number
1474 -1 common/cmd_ide.c Bad usage of "ide" command
1475 -1 common/cmd_ide.c No boot device
1476 -1 common/cmd_ide.c Unknown boot device
1477 -1 common/cmd_ide.c Unknown partition table
1478 -1 common/cmd_ide.c Invalid partition type
1479 -1 common/cmd_ide.c Read Error on boot device
1480 -1 common/cmd_ide.c Image header has bad magic number
1482 -1 common/cmd_nand.c Bad usage of "nand" command
1483 -1 common/cmd_nand.c No boot device
1484 -1 common/cmd_nand.c Unknown Chip ID on boot device
1485 -1 common/cmd_nand.c Read Error on boot device
1486 -1 common/cmd_nand.c Image header has bad magic number
1488 -1 common/env_common.c Environment has a bad CRC, using default
1494 [so far only for SMDK2400 and TRAB boards]
1496 - Modem support endable:
1497 CONFIG_MODEM_SUPPORT
1499 - RTS/CTS Flow control enable:
1502 - Modem debug support:
1503 CONFIG_MODEM_SUPPORT_DEBUG
1505 Enables debugging stuff (char screen[1024], dbg())
1506 for modem support. Useful only with BDI2000.
1508 - Interrupt support (PPC):
1510 There are common interrupt_init() and timer_interrupt()
1511 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1512 for cpu specific initialization. interrupt_init_cpu()
1513 should set decrementer_count to appropriate value. If
1514 cpu resets decrementer automatically after interrupt
1515 (ppc4xx) it should set decrementer_count to zero.
1516 timer_interrupt() calls timer_interrupt_cpu() for cpu
1517 specific handling. If board has watchdog / status_led
1518 / other_activity_monitor it works automatically from
1519 general timer_interrupt().
1523 In the target system modem support is enabled when a
1524 specific key (key combination) is pressed during
1525 power-on. Otherwise U-Boot will boot normally
1526 (autoboot). The key_pressed() fuction is called from
1527 board_init(). Currently key_pressed() is a dummy
1528 function, returning 1 and thus enabling modem
1531 If there are no modem init strings in the
1532 environment, U-Boot proceed to autoboot; the
1533 previous output (banner, info printfs) will be
1536 See also: doc/README.Modem
1539 Configuration Settings:
1540 -----------------------
1542 - CFG_LONGHELP: Defined when you want long help messages included;
1543 undefine this when you're short of memory.
1545 - CFG_PROMPT: This is what U-Boot prints on the console to
1546 prompt for user input.
1548 - CFG_CBSIZE: Buffer size for input from the Console
1550 - CFG_PBSIZE: Buffer size for Console output
1552 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1554 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1555 the application (usually a Linux kernel) when it is
1558 - CFG_BAUDRATE_TABLE:
1559 List of legal baudrate settings for this board.
1561 - CFG_CONSOLE_INFO_QUIET
1562 Suppress display of console information at boot.
1564 - CFG_CONSOLE_IS_IN_ENV
1565 If the board specific function
1566 extern int overwrite_console (void);
1567 returns 1, the stdin, stderr and stdout are switched to the
1568 serial port, else the settings in the environment are used.
1570 - CFG_CONSOLE_OVERWRITE_ROUTINE
1571 Enable the call to overwrite_console().
1573 - CFG_CONSOLE_ENV_OVERWRITE
1574 Enable overwrite of previous console environment settings.
1576 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1577 Begin and End addresses of the area used by the
1581 Enable an alternate, more extensive memory test.
1583 - CFG_MEMTEST_SCRATCH:
1584 Scratch address used by the alternate memory test
1585 You only need to set this if address zero isn't writeable
1587 - CFG_TFTP_LOADADDR:
1588 Default load address for network file downloads
1590 - CFG_LOADS_BAUD_CHANGE:
1591 Enable temporary baudrate change while serial download
1594 Physical start address of SDRAM. _Must_ be 0 here.
1597 Physical start address of Motherboard I/O (if using a
1601 Physical start address of Flash memory.
1604 Physical start address of boot monitor code (set by
1605 make config files to be same as the text base address
1606 (TEXT_BASE) used when linking) - same as
1607 CFG_FLASH_BASE when booting from flash.
1610 Size of memory reserved for monitor code, used to
1611 determine _at_compile_time_ (!) if the environment is
1612 embedded within the U-Boot image, or in a separate
1616 Size of DRAM reserved for malloc() use.
1619 Maximum size of memory mapped by the startup code of
1620 the Linux kernel; all data that must be processed by
1621 the Linux kernel (bd_info, boot arguments, eventually
1622 initrd image) must be put below this limit.
1624 - CFG_MAX_FLASH_BANKS:
1625 Max number of Flash memory banks
1627 - CFG_MAX_FLASH_SECT:
1628 Max number of sectors on a Flash chip
1630 - CFG_FLASH_ERASE_TOUT:
1631 Timeout for Flash erase operations (in ms)
1633 - CFG_FLASH_WRITE_TOUT:
1634 Timeout for Flash write operations (in ms)
1636 - CFG_FLASH_LOCK_TOUT
1637 Timeout for Flash set sector lock bit operation (in ms)
1639 - CFG_FLASH_UNLOCK_TOUT
1640 Timeout for Flash clear lock bits operation (in ms)
1642 - CFG_FLASH_PROTECTION
1643 If defined, hardware flash sectors protection is used
1644 instead of U-Boot software protection.
1646 - CFG_DIRECT_FLASH_TFTP:
1648 Enable TFTP transfers directly to flash memory;
1649 without this option such a download has to be
1650 performed in two steps: (1) download to RAM, and (2)
1651 copy from RAM to flash.
1653 The two-step approach is usually more reliable, since
1654 you can check if the download worked before you erase
1655 the flash, but in some situations (when sytem RAM is
1656 too limited to allow for a tempory copy of the
1657 downloaded image) this option may be very useful.
1660 Define if the flash driver uses extra elements in the
1661 common flash structure for storing flash geometry.
1663 - CFG_FLASH_CFI_DRIVER
1664 This option also enables the building of the cfi_flash driver
1665 in the drivers directory
1667 - CFG_RX_ETH_BUFFER:
1668 Defines the number of ethernet receive buffers. On some
1669 ethernet controllers it is recommended to set this value
1670 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1671 buffers can be full shortly after enabling the interface
1672 on high ethernet traffic.
1673 Defaults to 4 if not defined.
1675 The following definitions that deal with the placement and management
1676 of environment data (variable area); in general, we support the
1677 following configurations:
1679 - CFG_ENV_IS_IN_FLASH:
1681 Define this if the environment is in flash memory.
1683 a) The environment occupies one whole flash sector, which is
1684 "embedded" in the text segment with the U-Boot code. This
1685 happens usually with "bottom boot sector" or "top boot
1686 sector" type flash chips, which have several smaller
1687 sectors at the start or the end. For instance, such a
1688 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1689 such a case you would place the environment in one of the
1690 4 kB sectors - with U-Boot code before and after it. With
1691 "top boot sector" type flash chips, you would put the
1692 environment in one of the last sectors, leaving a gap
1693 between U-Boot and the environment.
1697 Offset of environment data (variable area) to the
1698 beginning of flash memory; for instance, with bottom boot
1699 type flash chips the second sector can be used: the offset
1700 for this sector is given here.
1702 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1706 This is just another way to specify the start address of
1707 the flash sector containing the environment (instead of
1710 - CFG_ENV_SECT_SIZE:
1712 Size of the sector containing the environment.
1715 b) Sometimes flash chips have few, equal sized, BIG sectors.
1716 In such a case you don't want to spend a whole sector for
1721 If you use this in combination with CFG_ENV_IS_IN_FLASH
1722 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1723 of this flash sector for the environment. This saves
1724 memory for the RAM copy of the environment.
1726 It may also save flash memory if you decide to use this
1727 when your environment is "embedded" within U-Boot code,
1728 since then the remainder of the flash sector could be used
1729 for U-Boot code. It should be pointed out that this is
1730 STRONGLY DISCOURAGED from a robustness point of view:
1731 updating the environment in flash makes it always
1732 necessary to erase the WHOLE sector. If something goes
1733 wrong before the contents has been restored from a copy in
1734 RAM, your target system will be dead.
1736 - CFG_ENV_ADDR_REDUND
1739 These settings describe a second storage area used to hold
1740 a redundand copy of the environment data, so that there is
1741 a valid backup copy in case there is a power failure during
1742 a "saveenv" operation.
1744 BE CAREFUL! Any changes to the flash layout, and some changes to the
1745 source code will make it necessary to adapt <board>/u-boot.lds*
1749 - CFG_ENV_IS_IN_NVRAM:
1751 Define this if you have some non-volatile memory device
1752 (NVRAM, battery buffered SRAM) which you want to use for the
1758 These two #defines are used to determin the memory area you
1759 want to use for environment. It is assumed that this memory
1760 can just be read and written to, without any special
1763 BE CAREFUL! The first access to the environment happens quite early
1764 in U-Boot initalization (when we try to get the setting of for the
1765 console baudrate). You *MUST* have mappend your NVRAM area then, or
1768 Please note that even with NVRAM we still use a copy of the
1769 environment in RAM: we could work on NVRAM directly, but we want to
1770 keep settings there always unmodified except somebody uses "saveenv"
1771 to save the current settings.
1774 - CFG_ENV_IS_IN_EEPROM:
1776 Use this if you have an EEPROM or similar serial access
1777 device and a driver for it.
1782 These two #defines specify the offset and size of the
1783 environment area within the total memory of your EEPROM.
1785 - CFG_I2C_EEPROM_ADDR:
1786 If defined, specified the chip address of the EEPROM device.
1787 The default address is zero.
1789 - CFG_EEPROM_PAGE_WRITE_BITS:
1790 If defined, the number of bits used to address bytes in a
1791 single page in the EEPROM device. A 64 byte page, for example
1792 would require six bits.
1794 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1795 If defined, the number of milliseconds to delay between
1796 page writes. The default is zero milliseconds.
1798 - CFG_I2C_EEPROM_ADDR_LEN:
1799 The length in bytes of the EEPROM memory array address. Note
1800 that this is NOT the chip address length!
1802 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1803 EEPROM chips that implement "address overflow" are ones
1804 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1805 address and the extra bits end up in the "chip address" bit
1806 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1809 Note that we consider the length of the address field to
1810 still be one byte because the extra address bits are hidden
1811 in the chip address.
1814 The size in bytes of the EEPROM device.
1817 - CFG_ENV_IS_IN_DATAFLASH:
1819 Define this if you have a DataFlash memory device which you
1820 want to use for the environment.
1826 These three #defines specify the offset and size of the
1827 environment area within the total memory of your DataFlash placed
1828 at the specified address.
1831 - CFG_SPI_INIT_OFFSET
1833 Defines offset to the initial SPI buffer area in DPRAM. The
1834 area is used at an early stage (ROM part) if the environment
1835 is configured to reside in the SPI EEPROM: We need a 520 byte
1836 scratch DPRAM area. It is used between the two initialization
1837 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1838 to be a good choice since it makes it far enough from the
1839 start of the data area as well as from the stack pointer.
1841 Please note that the environment is read-only as long as the monitor
1842 has been relocated to RAM and a RAM copy of the environment has been
1843 created; also, when using EEPROM you will have to use getenv_r()
1844 until then to read environment variables.
1846 The environment is protected by a CRC32 checksum. Before the monitor
1847 is relocated into RAM, as a result of a bad CRC you will be working
1848 with the compiled-in default environment - *silently*!!! [This is
1849 necessary, because the first environment variable we need is the
1850 "baudrate" setting for the console - if we have a bad CRC, we don't
1851 have any device yet where we could complain.]
1853 Note: once the monitor has been relocated, then it will complain if
1854 the default environment is used; a new CRC is computed as soon as you
1855 use the "saveenv" command to store a valid environment.
1857 - CFG_FAULT_ECHO_LINK_DOWN:
1858 Echo the inverted Ethernet link state to the fault LED.
1860 Note: If this option is active, then CFG_FAULT_MII_ADDR
1861 also needs to be defined.
1863 - CFG_FAULT_MII_ADDR:
1864 MII address of the PHY to check for the Ethernet link state.
1866 - CFG_64BIT_VSPRINTF:
1867 Makes vsprintf (and all *printf functions) support printing
1868 of 64bit values by using the L quantifier
1870 - CFG_64BIT_STRTOUL:
1871 Adds simple_strtoull that returns a 64bit value
1873 Low Level (hardware related) configuration options:
1874 ---------------------------------------------------
1876 - CFG_CACHELINE_SIZE:
1877 Cache Line Size of the CPU.
1880 Default address of the IMMR after system reset.
1882 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1883 and RPXsuper) to be able to adjust the position of
1884 the IMMR register after a reset.
1886 - Floppy Disk Support:
1887 CFG_FDC_DRIVE_NUMBER
1889 the default drive number (default value 0)
1893 defines the spacing between fdc chipset registers
1898 defines the offset of register from address. It
1899 depends on which part of the data bus is connected to
1900 the fdc chipset. (default value 0)
1902 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1903 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1906 if CFG_FDC_HW_INIT is defined, then the function
1907 fdc_hw_init() is called at the beginning of the FDC
1908 setup. fdc_hw_init() must be provided by the board
1909 source code. It is used to make hardware dependant
1912 - CFG_IMMR: Physical address of the Internal Memory Mapped
1913 Register; DO NOT CHANGE! (11-4)
1914 [MPC8xx systems only]
1916 - CFG_INIT_RAM_ADDR:
1918 Start address of memory area that can be used for
1919 initial data and stack; please note that this must be
1920 writable memory that is working WITHOUT special
1921 initialization, i. e. you CANNOT use normal RAM which
1922 will become available only after programming the
1923 memory controller and running certain initialization
1926 U-Boot uses the following memory types:
1927 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1928 - MPC824X: data cache
1929 - PPC4xx: data cache
1931 - CFG_GBL_DATA_OFFSET:
1933 Offset of the initial data structure in the memory
1934 area defined by CFG_INIT_RAM_ADDR. Usually
1935 CFG_GBL_DATA_OFFSET is chosen such that the initial
1936 data is located at the end of the available space
1937 (sometimes written as (CFG_INIT_RAM_END -
1938 CFG_INIT_DATA_SIZE), and the initial stack is just
1939 below that area (growing from (CFG_INIT_RAM_ADDR +
1940 CFG_GBL_DATA_OFFSET) downward.
1943 On the MPC824X (or other systems that use the data
1944 cache for initial memory) the address chosen for
1945 CFG_INIT_RAM_ADDR is basically arbitrary - it must
1946 point to an otherwise UNUSED address space between
1947 the top of RAM and the start of the PCI space.
1949 - CFG_SIUMCR: SIU Module Configuration (11-6)
1951 - CFG_SYPCR: System Protection Control (11-9)
1953 - CFG_TBSCR: Time Base Status and Control (11-26)
1955 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
1957 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
1959 - CFG_SCCR: System Clock and reset Control Register (15-27)
1961 - CFG_OR_TIMING_SDRAM:
1965 periodic timer for refresh
1967 - CFG_DER: Debug Event Register (37-47)
1969 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
1970 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
1971 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
1973 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
1975 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
1976 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
1977 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
1978 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
1980 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
1981 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
1982 Machine Mode Register and Memory Periodic Timer
1983 Prescaler definitions (SDRAM timing)
1985 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
1986 enable I2C microcode relocation patch (MPC8xx);
1987 define relocation offset in DPRAM [DSP2]
1989 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
1990 enable SPI microcode relocation patch (MPC8xx);
1991 define relocation offset in DPRAM [SCC4]
1994 Use OSCM clock mode on MBX8xx board. Be careful,
1995 wrong setting might damage your board. Read
1996 doc/README.MBX before setting this variable!
1998 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
1999 Offset of the bootmode word in DPRAM used by post
2000 (Power On Self Tests). This definition overrides
2001 #define'd default value in commproc.h resp.
2004 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2005 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2006 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2007 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2008 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2009 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2010 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2011 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2012 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2014 - CONFIG_ETHER_ON_FEC[12]
2015 Define to enable FEC[12] on a 8xx series processor.
2017 - CONFIG_FEC[12]_PHY
2018 Define to the hardcoded PHY address which corresponds
2019 to the given FEC; i. e.
2020 #define CONFIG_FEC1_PHY 4
2021 means that the PHY with address 4 is connected to FEC1
2023 When set to -1, means to probe for first available.
2025 - CONFIG_FEC[12]_PHY_NORXERR
2026 The PHY does not have a RXERR line (RMII only).
2027 (so program the FEC to ignore it).
2030 Enable RMII mode for all FECs.
2031 Note that this is a global option, we can't
2032 have one FEC in standard MII mode and another in RMII mode.
2034 - CONFIG_CRC32_VERIFY
2035 Add a verify option to the crc32 command.
2038 => crc32 -v <address> <count> <crc32>
2040 Where address/count indicate a memory area
2041 and crc32 is the correct crc32 which the
2044 Building the Software:
2045 ======================
2047 Building U-Boot has been tested in native PPC environments (on a
2048 PowerBook G3 running LinuxPPC 2000) and in cross environments
2049 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2052 If you are not using a native PPC environment, it is assumed that you
2053 have the GNU cross compiling tools available in your path and named
2054 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2055 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2056 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2059 CROSS_COMPILE = ppc_4xx-
2062 U-Boot is intended to be simple to build. After installing the
2063 sources you must configure U-Boot for one specific board type. This
2068 where "NAME_config" is the name of one of the existing
2069 configurations; the following names are supported:
2071 ADCIOP_config FPS860L_config omap730p2_config
2072 ADS860_config GEN860T_config pcu_e_config
2073 AR405_config GENIETV_config PIP405_config
2074 at91rm9200dk_config GTH_config QS823_config
2075 CANBT_config hermes_config QS850_config
2076 cmi_mpc5xx_config hymod_config QS860T_config
2077 cogent_common_config IP860_config RPXlite_config
2078 cogent_mpc8260_config IVML24_config RPXsuper_config
2079 cogent_mpc8xx_config IVMS8_config rsdproto_config
2080 CPCI405_config JSE_config Sandpoint8240_config
2081 CPCIISER4_config LANTEC_config sbc8260_config
2082 csb272_config lwmon_config SM850_config
2083 CU824_config MBX860T_config SPD823TS_config
2084 DUET_ADS_config MBX_config stxgp3_config
2085 EBONY_config MPC8260ADS_config SXNI855T_config
2086 ELPT860_config MPC8540ADS_config TQM823L_config
2087 ESTEEM192E_config MPC8560ADS_config TQM850L_config
2088 ETX094_config NETVIA_config TQM855L_config
2089 FADS823_config omap1510inn_config TQM860L_config
2090 FADS850SAR_config omap1610h2_config WALNUT405_config
2091 FADS860T_config omap1610inn_config ZPC1900_config
2092 FPS850L_config omap5912osk_config
2094 Note: for some board special configuration names may exist; check if
2095 additional information is available from the board vendor; for
2096 instance, the TQM823L systems are available without (standard)
2097 or with LCD support. You can select such additional "features"
2098 when chosing the configuration, i. e.
2101 - will configure for a plain TQM823L, i. e. no LCD support
2103 make TQM823L_LCD_config
2104 - will configure for a TQM823L with U-Boot console on LCD
2109 Finally, type "make all", and you should get some working U-Boot
2110 images ready for download to / installation on your system:
2112 - "u-boot.bin" is a raw binary image
2113 - "u-boot" is an image in ELF binary format
2114 - "u-boot.srec" is in Motorola S-Record format
2117 Please be aware that the Makefiles assume you are using GNU make, so
2118 for instance on NetBSD you might need to use "gmake" instead of
2122 If the system board that you have is not listed, then you will need
2123 to port U-Boot to your hardware platform. To do this, follow these
2126 1. Add a new configuration option for your board to the toplevel
2127 "Makefile" and to the "MAKEALL" script, using the existing
2128 entries as examples. Note that here and at many other places
2129 boards and other names are listed in alphabetical sort order. Please
2131 2. Create a new directory to hold your board specific code. Add any
2132 files you need. In your board directory, you will need at least
2133 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2134 3. Create a new configuration file "include/configs/<board>.h" for
2136 3. If you're porting U-Boot to a new CPU, then also create a new
2137 directory to hold your CPU specific code. Add any files you need.
2138 4. Run "make <board>_config" with your new name.
2139 5. Type "make", and you should get a working "u-boot.srec" file
2140 to be installed on your target system.
2141 6. Debug and solve any problems that might arise.
2142 [Of course, this last step is much harder than it sounds.]
2145 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2146 ==============================================================
2148 If you have modified U-Boot sources (for instance added a new board
2149 or support for new devices, a new CPU, etc.) you are expected to
2150 provide feedback to the other developers. The feedback normally takes
2151 the form of a "patch", i. e. a context diff against a certain (latest
2152 official or latest in CVS) version of U-Boot sources.
2154 But before you submit such a patch, please verify that your modifi-
2155 cation did not break existing code. At least make sure that *ALL* of
2156 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2157 just run the "MAKEALL" script, which will configure and build U-Boot
2158 for ALL supported system. Be warned, this will take a while. You can
2159 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2160 environment variable to the script, i. e. to use the cross tools from
2161 MontaVista's Hard Hat Linux you can type
2163 CROSS_COMPILE=ppc_8xx- MAKEALL
2165 or to build on a native PowerPC system you can type
2167 CROSS_COMPILE=' ' MAKEALL
2169 See also "U-Boot Porting Guide" below.
2172 Monitor Commands - Overview:
2173 ============================
2175 go - start application at address 'addr'
2176 run - run commands in an environment variable
2177 bootm - boot application image from memory
2178 bootp - boot image via network using BootP/TFTP protocol
2179 tftpboot- boot image via network using TFTP protocol
2180 and env variables "ipaddr" and "serverip"
2181 (and eventually "gatewayip")
2182 rarpboot- boot image via network using RARP/TFTP protocol
2183 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2184 loads - load S-Record file over serial line
2185 loadb - load binary file over serial line (kermit mode)
2187 mm - memory modify (auto-incrementing)
2188 nm - memory modify (constant address)
2189 mw - memory write (fill)
2191 cmp - memory compare
2192 crc32 - checksum calculation
2193 imd - i2c memory display
2194 imm - i2c memory modify (auto-incrementing)
2195 inm - i2c memory modify (constant address)
2196 imw - i2c memory write (fill)
2197 icrc32 - i2c checksum calculation
2198 iprobe - probe to discover valid I2C chip addresses
2199 iloop - infinite loop on address range
2200 isdram - print SDRAM configuration information
2201 sspi - SPI utility commands
2202 base - print or set address offset
2203 printenv- print environment variables
2204 setenv - set environment variables
2205 saveenv - save environment variables to persistent storage
2206 protect - enable or disable FLASH write protection
2207 erase - erase FLASH memory
2208 flinfo - print FLASH memory information
2209 bdinfo - print Board Info structure
2210 iminfo - print header information for application image
2211 coninfo - print console devices and informations
2212 ide - IDE sub-system
2213 loop - infinite loop on address range
2214 mtest - simple RAM test
2215 icache - enable or disable instruction cache
2216 dcache - enable or disable data cache
2217 reset - Perform RESET of the CPU
2218 echo - echo args to console
2219 version - print monitor version
2220 help - print online help
2221 ? - alias for 'help'
2224 Monitor Commands - Detailed Description:
2225 ========================================
2229 For now: just type "help <command>".
2232 Environment Variables:
2233 ======================
2235 U-Boot supports user configuration using Environment Variables which
2236 can be made persistent by saving to Flash memory.
2238 Environment Variables are set using "setenv", printed using
2239 "printenv", and saved to Flash using "saveenv". Using "setenv"
2240 without a value can be used to delete a variable from the
2241 environment. As long as you don't save the environment you are
2242 working with an in-memory copy. In case the Flash area containing the
2243 environment is erased by accident, a default environment is provided.
2245 Some configuration options can be set using Environment Variables:
2247 baudrate - see CONFIG_BAUDRATE
2249 bootdelay - see CONFIG_BOOTDELAY
2251 bootcmd - see CONFIG_BOOTCOMMAND
2253 bootargs - Boot arguments when booting an RTOS image
2255 bootfile - Name of the image to load with TFTP
2257 autoload - if set to "no" (any string beginning with 'n'),
2258 "bootp" will just load perform a lookup of the
2259 configuration from the BOOTP server, but not try to
2260 load any image using TFTP
2262 autostart - if set to "yes", an image loaded using the "bootp",
2263 "rarpboot", "tftpboot" or "diskboot" commands will
2264 be automatically started (by internally calling
2267 If set to "no", a standalone image passed to the
2268 "bootm" command will be copied to the load address
2269 (and eventually uncompressed), but NOT be started.
2270 This can be used to load and uncompress arbitrary
2273 i2cfast - (PPC405GP|PPC405EP only)
2274 if set to 'y' configures Linux I2C driver for fast
2275 mode (400kHZ). This environment variable is used in
2276 initialization code. So, for changes to be effective
2277 it must be saved and board must be reset.
2279 initrd_high - restrict positioning of initrd images:
2280 If this variable is not set, initrd images will be
2281 copied to the highest possible address in RAM; this
2282 is usually what you want since it allows for
2283 maximum initrd size. If for some reason you want to
2284 make sure that the initrd image is loaded below the
2285 CFG_BOOTMAPSZ limit, you can set this environment
2286 variable to a value of "no" or "off" or "0".
2287 Alternatively, you can set it to a maximum upper
2288 address to use (U-Boot will still check that it
2289 does not overwrite the U-Boot stack and data).
2291 For instance, when you have a system with 16 MB
2292 RAM, and want to reserve 4 MB from use by Linux,
2293 you can do this by adding "mem=12M" to the value of
2294 the "bootargs" variable. However, now you must make
2295 sure that the initrd image is placed in the first
2296 12 MB as well - this can be done with
2298 setenv initrd_high 00c00000
2300 If you set initrd_high to 0xFFFFFFFF, this is an
2301 indication to U-Boot that all addresses are legal
2302 for the Linux kernel, including addresses in flash
2303 memory. In this case U-Boot will NOT COPY the
2304 ramdisk at all. This may be useful to reduce the
2305 boot time on your system, but requires that this
2306 feature is supported by your Linux kernel.
2308 ipaddr - IP address; needed for tftpboot command
2310 loadaddr - Default load address for commands like "bootp",
2311 "rarpboot", "tftpboot", "loadb" or "diskboot"
2313 loads_echo - see CONFIG_LOADS_ECHO
2315 serverip - TFTP server IP address; needed for tftpboot command
2317 bootretry - see CONFIG_BOOT_RETRY_TIME
2319 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2321 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2323 ethprime - When CONFIG_NET_MULTI is enabled controls which
2324 interface is used first.
2326 ethact - When CONFIG_NET_MULTI is enabled controls which
2327 interface is currently active. For example you
2328 can do the following
2330 => setenv ethact FEC ETHERNET
2331 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2332 => setenv ethact SCC ETHERNET
2333 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2335 netretry - When set to "no" each network operation will
2336 either succeed or fail without retrying.
2337 When set to "once" the network operation will
2338 fail when all the available network interfaces
2339 are tried once without success.
2340 Useful on scripts which control the retry operation
2343 vlan - When set to a value < 4095 the traffic over
2344 ethernet is encapsulated/received over 802.1q
2347 The following environment variables may be used and automatically
2348 updated by the network boot commands ("bootp" and "rarpboot"),
2349 depending the information provided by your boot server:
2351 bootfile - see above
2352 dnsip - IP address of your Domain Name Server
2353 dnsip2 - IP address of your secondary Domain Name Server
2354 gatewayip - IP address of the Gateway (Router) to use
2355 hostname - Target hostname
2357 netmask - Subnet Mask
2358 rootpath - Pathname of the root filesystem on the NFS server
2359 serverip - see above
2362 There are two special Environment Variables:
2364 serial# - contains hardware identification information such
2365 as type string and/or serial number
2366 ethaddr - Ethernet address
2368 These variables can be set only once (usually during manufacturing of
2369 the board). U-Boot refuses to delete or overwrite these variables
2370 once they have been set once.
2373 Further special Environment Variables:
2375 ver - Contains the U-Boot version string as printed
2376 with the "version" command. This variable is
2377 readonly (see CONFIG_VERSION_VARIABLE).
2380 Please note that changes to some configuration parameters may take
2381 only effect after the next boot (yes, that's just like Windoze :-).
2384 Command Line Parsing:
2385 =====================
2387 There are two different command line parsers available with U-Boot:
2388 the old "simple" one, and the much more powerful "hush" shell:
2390 Old, simple command line parser:
2391 --------------------------------
2393 - supports environment variables (through setenv / saveenv commands)
2394 - several commands on one line, separated by ';'
2395 - variable substitution using "... $(name) ..." syntax
2396 - special characters ('$', ';') can be escaped by prefixing with '\',
2398 setenv bootcmd bootm \$(address)
2399 - You can also escape text by enclosing in single apostrophes, for example:
2400 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2405 - similar to Bourne shell, with control structures like
2406 if...then...else...fi, for...do...done; while...do...done,
2407 until...do...done, ...
2408 - supports environment ("global") variables (through setenv / saveenv
2409 commands) and local shell variables (through standard shell syntax
2410 "name=value"); only environment variables can be used with "run"
2416 (1) If a command line (or an environment variable executed by a "run"
2417 command) contains several commands separated by semicolon, and
2418 one of these commands fails, then the remaining commands will be
2421 (2) If you execute several variables with one call to run (i. e.
2422 calling run with a list af variables as arguments), any failing
2423 command will cause "run" to terminate, i. e. the remaining
2424 variables are not executed.
2426 Note for Redundant Ethernet Interfaces:
2427 =======================================
2429 Some boards come with redundant ethernet interfaces; U-Boot supports
2430 such configurations and is capable of automatic selection of a
2431 "working" interface when needed. MAC assignment works as follows:
2433 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2434 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2435 "eth1addr" (=>eth1), "eth2addr", ...
2437 If the network interface stores some valid MAC address (for instance
2438 in SROM), this is used as default address if there is NO correspon-
2439 ding setting in the environment; if the corresponding environment
2440 variable is set, this overrides the settings in the card; that means:
2442 o If the SROM has a valid MAC address, and there is no address in the
2443 environment, the SROM's address is used.
2445 o If there is no valid address in the SROM, and a definition in the
2446 environment exists, then the value from the environment variable is
2449 o If both the SROM and the environment contain a MAC address, and
2450 both addresses are the same, this MAC address is used.
2452 o If both the SROM and the environment contain a MAC address, and the
2453 addresses differ, the value from the environment is used and a
2456 o If neither SROM nor the environment contain a MAC address, an error
2463 The "boot" commands of this monitor operate on "image" files which
2464 can be basicly anything, preceeded by a special header; see the
2465 definitions in include/image.h for details; basicly, the header
2466 defines the following image properties:
2468 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2469 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2470 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2471 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2472 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2473 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2474 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2475 * Compression Type (uncompressed, gzip, bzip2)
2481 The header is marked by a special Magic Number, and both the header
2482 and the data portions of the image are secured against corruption by
2489 Although U-Boot should support any OS or standalone application
2490 easily, the main focus has always been on Linux during the design of
2493 U-Boot includes many features that so far have been part of some
2494 special "boot loader" code within the Linux kernel. Also, any
2495 "initrd" images to be used are no longer part of one big Linux image;
2496 instead, kernel and "initrd" are separate images. This implementation
2497 serves several purposes:
2499 - the same features can be used for other OS or standalone
2500 applications (for instance: using compressed images to reduce the
2501 Flash memory footprint)
2503 - it becomes much easier to port new Linux kernel versions because
2504 lots of low-level, hardware dependent stuff are done by U-Boot
2506 - the same Linux kernel image can now be used with different "initrd"
2507 images; of course this also means that different kernel images can
2508 be run with the same "initrd". This makes testing easier (you don't
2509 have to build a new "zImage.initrd" Linux image when you just
2510 change a file in your "initrd"). Also, a field-upgrade of the
2511 software is easier now.
2517 Porting Linux to U-Boot based systems:
2518 ---------------------------------------
2520 U-Boot cannot save you from doing all the necessary modifications to
2521 configure the Linux device drivers for use with your target hardware
2522 (no, we don't intend to provide a full virtual machine interface to
2525 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2527 Just make sure your machine specific header file (for instance
2528 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2529 Information structure as we define in include/u-boot.h, and make
2530 sure that your definition of IMAP_ADDR uses the same value as your
2531 U-Boot configuration in CFG_IMMR.
2534 Configuring the Linux kernel:
2535 -----------------------------
2537 No specific requirements for U-Boot. Make sure you have some root
2538 device (initial ramdisk, NFS) for your target system.
2541 Building a Linux Image:
2542 -----------------------
2544 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2545 not used. If you use recent kernel source, a new build target
2546 "uImage" will exist which automatically builds an image usable by
2547 U-Boot. Most older kernels also have support for a "pImage" target,
2548 which was introduced for our predecessor project PPCBoot and uses a
2549 100% compatible format.
2558 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2559 encapsulate a compressed Linux kernel image with header information,
2560 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2562 * build a standard "vmlinux" kernel image (in ELF binary format):
2564 * convert the kernel into a raw binary image:
2566 ${CROSS_COMPILE}-objcopy -O binary \
2567 -R .note -R .comment \
2568 -S vmlinux linux.bin
2570 * compress the binary image:
2574 * package compressed binary image for U-Boot:
2576 mkimage -A ppc -O linux -T kernel -C gzip \
2577 -a 0 -e 0 -n "Linux Kernel Image" \
2578 -d linux.bin.gz uImage
2581 The "mkimage" tool can also be used to create ramdisk images for use
2582 with U-Boot, either separated from the Linux kernel image, or
2583 combined into one file. "mkimage" encapsulates the images with a 64
2584 byte header containing information about target architecture,
2585 operating system, image type, compression method, entry points, time
2586 stamp, CRC32 checksums, etc.
2588 "mkimage" can be called in two ways: to verify existing images and
2589 print the header information, or to build new images.
2591 In the first form (with "-l" option) mkimage lists the information
2592 contained in the header of an existing U-Boot image; this includes
2593 checksum verification:
2595 tools/mkimage -l image
2596 -l ==> list image header information
2598 The second form (with "-d" option) is used to build a U-Boot image
2599 from a "data file" which is used as image payload:
2601 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2602 -n name -d data_file image
2603 -A ==> set architecture to 'arch'
2604 -O ==> set operating system to 'os'
2605 -T ==> set image type to 'type'
2606 -C ==> set compression type 'comp'
2607 -a ==> set load address to 'addr' (hex)
2608 -e ==> set entry point to 'ep' (hex)
2609 -n ==> set image name to 'name'
2610 -d ==> use image data from 'datafile'
2612 Right now, all Linux kernels for PowerPC systems use the same load
2613 address (0x00000000), but the entry point address depends on the
2616 - 2.2.x kernels have the entry point at 0x0000000C,
2617 - 2.3.x and later kernels have the entry point at 0x00000000.
2619 So a typical call to build a U-Boot image would read:
2621 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2622 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2623 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2624 > examples/uImage.TQM850L
2625 Image Name: 2.4.4 kernel for TQM850L
2626 Created: Wed Jul 19 02:34:59 2000
2627 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2628 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2629 Load Address: 0x00000000
2630 Entry Point: 0x00000000
2632 To verify the contents of the image (or check for corruption):
2634 -> tools/mkimage -l examples/uImage.TQM850L
2635 Image Name: 2.4.4 kernel for TQM850L
2636 Created: Wed Jul 19 02:34:59 2000
2637 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2638 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2639 Load Address: 0x00000000
2640 Entry Point: 0x00000000
2642 NOTE: for embedded systems where boot time is critical you can trade
2643 speed for memory and install an UNCOMPRESSED image instead: this
2644 needs more space in Flash, but boots much faster since it does not
2645 need to be uncompressed:
2647 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2648 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2649 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2650 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2651 > examples/uImage.TQM850L-uncompressed
2652 Image Name: 2.4.4 kernel for TQM850L
2653 Created: Wed Jul 19 02:34:59 2000
2654 Image Type: PowerPC Linux Kernel Image (uncompressed)
2655 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2656 Load Address: 0x00000000
2657 Entry Point: 0x00000000
2660 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2661 when your kernel is intended to use an initial ramdisk:
2663 -> tools/mkimage -n 'Simple Ramdisk Image' \
2664 > -A ppc -O linux -T ramdisk -C gzip \
2665 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2666 Image Name: Simple Ramdisk Image
2667 Created: Wed Jan 12 14:01:50 2000
2668 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2669 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2670 Load Address: 0x00000000
2671 Entry Point: 0x00000000
2674 Installing a Linux Image:
2675 -------------------------
2677 To downloading a U-Boot image over the serial (console) interface,
2678 you must convert the image to S-Record format:
2680 objcopy -I binary -O srec examples/image examples/image.srec
2682 The 'objcopy' does not understand the information in the U-Boot
2683 image header, so the resulting S-Record file will be relative to
2684 address 0x00000000. To load it to a given address, you need to
2685 specify the target address as 'offset' parameter with the 'loads'
2688 Example: install the image to address 0x40100000 (which on the
2689 TQM8xxL is in the first Flash bank):
2691 => erase 40100000 401FFFFF
2697 ## Ready for S-Record download ...
2698 ~>examples/image.srec
2699 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2701 15989 15990 15991 15992
2702 [file transfer complete]
2704 ## Start Addr = 0x00000000
2707 You can check the success of the download using the 'iminfo' command;
2708 this includes a checksum verification so you can be sure no data
2709 corruption happened:
2713 ## Checking Image at 40100000 ...
2714 Image Name: 2.2.13 for initrd on TQM850L
2715 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2716 Data Size: 335725 Bytes = 327 kB = 0 MB
2717 Load Address: 00000000
2718 Entry Point: 0000000c
2719 Verifying Checksum ... OK
2725 The "bootm" command is used to boot an application that is stored in
2726 memory (RAM or Flash). In case of a Linux kernel image, the contents
2727 of the "bootargs" environment variable is passed to the kernel as
2728 parameters. You can check and modify this variable using the
2729 "printenv" and "setenv" commands:
2732 => printenv bootargs
2733 bootargs=root=/dev/ram
2735 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2737 => printenv bootargs
2738 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2741 ## Booting Linux kernel at 40020000 ...
2742 Image Name: 2.2.13 for NFS on TQM850L
2743 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2744 Data Size: 381681 Bytes = 372 kB = 0 MB
2745 Load Address: 00000000
2746 Entry Point: 0000000c
2747 Verifying Checksum ... OK
2748 Uncompressing Kernel Image ... OK
2749 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
2750 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2751 time_init: decrementer frequency = 187500000/60
2752 Calibrating delay loop... 49.77 BogoMIPS
2753 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2756 If you want to boot a Linux kernel with initial ram disk, you pass
2757 the memory addresses of both the kernel and the initrd image (PPBCOOT
2758 format!) to the "bootm" command:
2760 => imi 40100000 40200000
2762 ## Checking Image at 40100000 ...
2763 Image Name: 2.2.13 for initrd on TQM850L
2764 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2765 Data Size: 335725 Bytes = 327 kB = 0 MB
2766 Load Address: 00000000
2767 Entry Point: 0000000c
2768 Verifying Checksum ... OK
2770 ## Checking Image at 40200000 ...
2771 Image Name: Simple Ramdisk Image
2772 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2773 Data Size: 566530 Bytes = 553 kB = 0 MB
2774 Load Address: 00000000
2775 Entry Point: 00000000
2776 Verifying Checksum ... OK
2778 => bootm 40100000 40200000
2779 ## Booting Linux kernel at 40100000 ...
2780 Image Name: 2.2.13 for initrd on TQM850L
2781 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2782 Data Size: 335725 Bytes = 327 kB = 0 MB
2783 Load Address: 00000000
2784 Entry Point: 0000000c
2785 Verifying Checksum ... OK
2786 Uncompressing Kernel Image ... OK
2787 ## Loading RAMDisk Image at 40200000 ...
2788 Image Name: Simple Ramdisk Image
2789 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2790 Data Size: 566530 Bytes = 553 kB = 0 MB
2791 Load Address: 00000000
2792 Entry Point: 00000000
2793 Verifying Checksum ... OK
2794 Loading Ramdisk ... OK
2795 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
2796 Boot arguments: root=/dev/ram
2797 time_init: decrementer frequency = 187500000/60
2798 Calibrating delay loop... 49.77 BogoMIPS
2800 RAMDISK: Compressed image found at block 0
2801 VFS: Mounted root (ext2 filesystem).
2805 More About U-Boot Image Types:
2806 ------------------------------
2808 U-Boot supports the following image types:
2810 "Standalone Programs" are directly runnable in the environment
2811 provided by U-Boot; it is expected that (if they behave
2812 well) you can continue to work in U-Boot after return from
2813 the Standalone Program.
2814 "OS Kernel Images" are usually images of some Embedded OS which
2815 will take over control completely. Usually these programs
2816 will install their own set of exception handlers, device
2817 drivers, set up the MMU, etc. - this means, that you cannot
2818 expect to re-enter U-Boot except by resetting the CPU.
2819 "RAMDisk Images" are more or less just data blocks, and their
2820 parameters (address, size) are passed to an OS kernel that is
2822 "Multi-File Images" contain several images, typically an OS
2823 (Linux) kernel image and one or more data images like
2824 RAMDisks. This construct is useful for instance when you want
2825 to boot over the network using BOOTP etc., where the boot
2826 server provides just a single image file, but you want to get
2827 for instance an OS kernel and a RAMDisk image.
2829 "Multi-File Images" start with a list of image sizes, each
2830 image size (in bytes) specified by an "uint32_t" in network
2831 byte order. This list is terminated by an "(uint32_t)0".
2832 Immediately after the terminating 0 follow the images, one by
2833 one, all aligned on "uint32_t" boundaries (size rounded up to
2834 a multiple of 4 bytes).
2836 "Firmware Images" are binary images containing firmware (like
2837 U-Boot or FPGA images) which usually will be programmed to
2840 "Script files" are command sequences that will be executed by
2841 U-Boot's command interpreter; this feature is especially
2842 useful when you configure U-Boot to use a real shell (hush)
2843 as command interpreter.
2849 One of the features of U-Boot is that you can dynamically load and
2850 run "standalone" applications, which can use some resources of
2851 U-Boot like console I/O functions or interrupt services.
2853 Two simple examples are included with the sources:
2858 'examples/hello_world.c' contains a small "Hello World" Demo
2859 application; it is automatically compiled when you build U-Boot.
2860 It's configured to run at address 0x00040004, so you can play with it
2864 ## Ready for S-Record download ...
2865 ~>examples/hello_world.srec
2866 1 2 3 4 5 6 7 8 9 10 11 ...
2867 [file transfer complete]
2869 ## Start Addr = 0x00040004
2871 => go 40004 Hello World! This is a test.
2872 ## Starting application at 0x00040004 ...
2883 Hit any key to exit ...
2885 ## Application terminated, rc = 0x0
2887 Another example, which demonstrates how to register a CPM interrupt
2888 handler with the U-Boot code, can be found in 'examples/timer.c'.
2889 Here, a CPM timer is set up to generate an interrupt every second.
2890 The interrupt service routine is trivial, just printing a '.'
2891 character, but this is just a demo program. The application can be
2892 controlled by the following keys:
2894 ? - print current values og the CPM Timer registers
2895 b - enable interrupts and start timer
2896 e - stop timer and disable interrupts
2897 q - quit application
2900 ## Ready for S-Record download ...
2901 ~>examples/timer.srec
2902 1 2 3 4 5 6 7 8 9 10 11 ...
2903 [file transfer complete]
2905 ## Start Addr = 0x00040004
2908 ## Starting application at 0x00040004 ...
2911 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
2914 [q, b, e, ?] Set interval 1000000 us
2917 [q, b, e, ?] ........
2918 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2921 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2924 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2927 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2929 [q, b, e, ?] ...Stopping timer
2931 [q, b, e, ?] ## Application terminated, rc = 0x0
2937 Over time, many people have reported problems when trying to use the
2938 "minicom" terminal emulation program for serial download. I (wd)
2939 consider minicom to be broken, and recommend not to use it. Under
2940 Unix, I recommend to use C-Kermit for general purpose use (and
2941 especially for kermit binary protocol download ("loadb" command), and
2942 use "cu" for S-Record download ("loads" command).
2944 Nevertheless, if you absolutely want to use it try adding this
2945 configuration to your "File transfer protocols" section:
2947 Name Program Name U/D FullScr IO-Red. Multi
2948 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2949 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
2955 Starting at version 0.9.2, U-Boot supports NetBSD both as host
2956 (build U-Boot) and target system (boots NetBSD/mpc8xx).
2958 Building requires a cross environment; it is known to work on
2959 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2960 need gmake since the Makefiles are not compatible with BSD make).
2961 Note that the cross-powerpc package does not install include files;
2962 attempting to build U-Boot will fail because <machine/ansi.h> is
2963 missing. This file has to be installed and patched manually:
2965 # cd /usr/pkg/cross/powerpc-netbsd/include
2967 # ln -s powerpc machine
2968 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2969 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
2971 Native builds *don't* work due to incompatibilities between native
2972 and U-Boot include files.
2974 Booting assumes that (the first part of) the image booted is a
2975 stage-2 loader which in turn loads and then invokes the kernel
2976 proper. Loader sources will eventually appear in the NetBSD source
2977 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
2978 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
2982 Implementation Internals:
2983 =========================
2985 The following is not intended to be a complete description of every
2986 implementation detail. However, it should help to understand the
2987 inner workings of U-Boot and make it easier to port it to custom
2991 Initial Stack, Global Data:
2992 ---------------------------
2994 The implementation of U-Boot is complicated by the fact that U-Boot
2995 starts running out of ROM (flash memory), usually without access to
2996 system RAM (because the memory controller is not initialized yet).
2997 This means that we don't have writable Data or BSS segments, and BSS
2998 is not initialized as zero. To be able to get a C environment working
2999 at all, we have to allocate at least a minimal stack. Implementation
3000 options for this are defined and restricted by the CPU used: Some CPU
3001 models provide on-chip memory (like the IMMR area on MPC8xx and
3002 MPC826x processors), on others (parts of) the data cache can be
3003 locked as (mis-) used as memory, etc.
3005 Chris Hallinan posted a good summary of these issues to the
3006 u-boot-users mailing list:
3008 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3009 From: "Chris Hallinan" <clh@net1plus.com>
3010 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3013 Correct me if I'm wrong, folks, but the way I understand it
3014 is this: Using DCACHE as initial RAM for Stack, etc, does not
3015 require any physical RAM backing up the cache. The cleverness
3016 is that the cache is being used as a temporary supply of
3017 necessary storage before the SDRAM controller is setup. It's
3018 beyond the scope of this list to expain the details, but you
3019 can see how this works by studying the cache architecture and
3020 operation in the architecture and processor-specific manuals.
3022 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3023 is another option for the system designer to use as an
3024 initial stack/ram area prior to SDRAM being available. Either
3025 option should work for you. Using CS 4 should be fine if your
3026 board designers haven't used it for something that would
3027 cause you grief during the initial boot! It is frequently not
3030 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3031 with your processor/board/system design. The default value
3032 you will find in any recent u-boot distribution in
3033 Walnut405.h should work for you. I'd set it to a value larger
3034 than your SDRAM module. If you have a 64MB SDRAM module, set
3035 it above 400_0000. Just make sure your board has no resources
3036 that are supposed to respond to that address! That code in
3037 start.S has been around a while and should work as is when
3038 you get the config right.
3043 It is essential to remember this, since it has some impact on the C
3044 code for the initialization procedures:
3046 * Initialized global data (data segment) is read-only. Do not attempt
3049 * Do not use any unitialized global data (or implicitely initialized
3050 as zero data - BSS segment) at all - this is undefined, initiali-
3051 zation is performed later (when relocating to RAM).
3053 * Stack space is very limited. Avoid big data buffers or things like
3056 Having only the stack as writable memory limits means we cannot use
3057 normal global data to share information beween the code. But it
3058 turned out that the implementation of U-Boot can be greatly
3059 simplified by making a global data structure (gd_t) available to all
3060 functions. We could pass a pointer to this data as argument to _all_
3061 functions, but this would bloat the code. Instead we use a feature of
3062 the GCC compiler (Global Register Variables) to share the data: we
3063 place a pointer (gd) to the global data into a register which we
3064 reserve for this purpose.
3066 When choosing a register for such a purpose we are restricted by the
3067 relevant (E)ABI specifications for the current architecture, and by
3068 GCC's implementation.
3070 For PowerPC, the following registers have specific use:
3073 R3-R4: parameter passing and return values
3074 R5-R10: parameter passing
3075 R13: small data area pointer
3079 (U-Boot also uses R14 as internal GOT pointer.)
3081 ==> U-Boot will use R29 to hold a pointer to the global data
3083 Note: on PPC, we could use a static initializer (since the
3084 address of the global data structure is known at compile time),
3085 but it turned out that reserving a register results in somewhat
3086 smaller code - although the code savings are not that big (on
3087 average for all boards 752 bytes for the whole U-Boot image,
3088 624 text + 127 data).
3090 On ARM, the following registers are used:
3092 R0: function argument word/integer result
3093 R1-R3: function argument word
3095 R10: stack limit (used only if stack checking if enabled)
3096 R11: argument (frame) pointer
3097 R12: temporary workspace
3100 R15: program counter
3102 ==> U-Boot will use R8 to hold a pointer to the global data
3108 U-Boot runs in system state and uses physical addresses, i.e. the
3109 MMU is not used either for address mapping nor for memory protection.
3111 The available memory is mapped to fixed addresses using the memory
3112 controller. In this process, a contiguous block is formed for each
3113 memory type (Flash, SDRAM, SRAM), even when it consists of several
3114 physical memory banks.
3116 U-Boot is installed in the first 128 kB of the first Flash bank (on
3117 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3118 booting and sizing and initializing DRAM, the code relocates itself
3119 to the upper end of DRAM. Immediately below the U-Boot code some
3120 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3121 configuration setting]. Below that, a structure with global Board
3122 Info data is placed, followed by the stack (growing downward).
3124 Additionally, some exception handler code is copied to the low 8 kB
3125 of DRAM (0x00000000 ... 0x00001FFF).
3127 So a typical memory configuration with 16 MB of DRAM could look like
3130 0x0000 0000 Exception Vector code
3133 0x0000 2000 Free for Application Use
3139 0x00FB FF20 Monitor Stack (Growing downward)
3140 0x00FB FFAC Board Info Data and permanent copy of global data
3141 0x00FC 0000 Malloc Arena
3144 0x00FE 0000 RAM Copy of Monitor Code
3145 ... eventually: LCD or video framebuffer
3146 ... eventually: pRAM (Protected RAM - unchanged by reset)
3147 0x00FF FFFF [End of RAM]
3150 System Initialization:
3151 ----------------------
3153 In the reset configuration, U-Boot starts at the reset entry point
3154 (on most PowerPC systens at address 0x00000100). Because of the reset
3155 configuration for CS0# this is a mirror of the onboard Flash memory.
3156 To be able to re-map memory U-Boot then jumps to its link address.
3157 To be able to implement the initialization code in C, a (small!)
3158 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3159 which provide such a feature like MPC8xx or MPC8260), or in a locked
3160 part of the data cache. After that, U-Boot initializes the CPU core,
3161 the caches and the SIU.
3163 Next, all (potentially) available memory banks are mapped using a
3164 preliminary mapping. For example, we put them on 512 MB boundaries
3165 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3166 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3167 programmed for SDRAM access. Using the temporary configuration, a
3168 simple memory test is run that determines the size of the SDRAM
3171 When there is more than one SDRAM bank, and the banks are of
3172 different size, the largest is mapped first. For equal size, the first
3173 bank (CS2#) is mapped first. The first mapping is always for address
3174 0x00000000, with any additional banks following immediately to create
3175 contiguous memory starting from 0.
3177 Then, the monitor installs itself at the upper end of the SDRAM area
3178 and allocates memory for use by malloc() and for the global Board
3179 Info data; also, the exception vector code is copied to the low RAM
3180 pages, and the final stack is set up.
3182 Only after this relocation will you have a "normal" C environment;
3183 until that you are restricted in several ways, mostly because you are
3184 running from ROM, and because the code will have to be relocated to a
3188 U-Boot Porting Guide:
3189 ----------------------
3191 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3195 int main (int argc, char *argv[])
3197 sighandler_t no_more_time;
3199 signal (SIGALRM, no_more_time);
3200 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3202 if (available_money > available_manpower) {
3203 pay consultant to port U-Boot;
3207 Download latest U-Boot source;
3209 Subscribe to u-boot-users mailing list;
3212 email ("Hi, I am new to U-Boot, how do I get started?");
3216 Read the README file in the top level directory;
3217 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3218 Read the source, Luke;
3221 if (available_money > toLocalCurrency ($2500)) {
3224 Add a lot of aggravation and time;
3227 Create your own board support subdirectory;
3229 Create your own board config file;
3233 Add / modify source code;
3237 email ("Hi, I am having problems...");
3239 Send patch file to Wolfgang;
3244 void no_more_time (int sig)
3253 All contributions to U-Boot should conform to the Linux kernel
3254 coding style; see the file "Documentation/CodingStyle" in your Linux
3255 kernel source directory.
3257 Please note that U-Boot is implemented in C (and to some small parts
3258 in Assembler); no C++ is used, so please do not use C++ style
3259 comments (//) in your code.
3261 Please also stick to the following formatting rules:
3262 - remove any trailing white space
3263 - use TAB characters for indentation, not spaces
3264 - make sure NOT to use DOS '\r\n' line feeds
3265 - do not add more than 2 empty lines to source files
3266 - do not add trailing empty lines to source files
3268 Submissions which do not conform to the standards may be returned
3269 with a request to reformat the changes.
3275 Since the number of patches for U-Boot is growing, we need to
3276 establish some rules. Submissions which do not conform to these rules
3277 may be rejected, even when they contain important and valuable stuff.
3280 When you send a patch, please include the following information with
3283 * For bug fixes: a description of the bug and how your patch fixes
3284 this bug. Please try to include a way of demonstrating that the
3285 patch actually fixes something.
3287 * For new features: a description of the feature and your
3290 * A CHANGELOG entry as plaintext (separate from the patch)
3292 * For major contributions, your entry to the CREDITS file
3294 * When you add support for a new board, don't forget to add this
3295 board to the MAKEALL script, too.
3297 * If your patch adds new configuration options, don't forget to
3298 document these in the README file.
3300 * The patch itself. If you are accessing the CVS repository use "cvs
3301 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3302 version of diff does not support these options, then get the latest
3303 version of GNU diff.
3305 The current directory when running this command shall be the top
3306 level directory of the U-Boot source tree, or it's parent directory
3307 (i. e. please make sure that your patch includes sufficient
3308 directory information for the affected files).
3310 We accept patches as plain text, MIME attachments or as uuencoded
3313 * If one logical set of modifications affects or creates several
3314 files, all these changes shall be submitted in a SINGLE patch file.
3316 * Changesets that contain different, unrelated modifications shall be
3317 submitted as SEPARATE patches, one patch per changeset.
3322 * Before sending the patch, run the MAKEALL script on your patched
3323 source tree and make sure that no errors or warnings are reported
3324 for any of the boards.
3326 * Keep your modifications to the necessary minimum: A patch
3327 containing several unrelated changes or arbitrary reformats will be
3328 returned with a request to re-formatting / split it.
3330 * If you modify existing code, make sure that your new code does not
3331 add to the memory footprint of the code ;-) Small is beautiful!
3332 When adding new features, these should compile conditionally only
3333 (using #ifdef), and the resulting code with the new feature
3334 disabled must not need more memory than the old code without your