1# 2# (C) Copyright 2000 - 2008 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 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. 12# 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. 17# 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, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot-users@lists.sourceforge.net>. There is also an archive of 64previous traffic on the mailing list - please search the archive 65before asking FAQ's. Please see 66http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Ofifcial releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/UBoot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129U-Boot uses a 3 level version number containing a version, a 130sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 131sub-version "34", and patchlevel "4". 132 133The patchlevel is used to indicate certain stages of development 134between released versions, i. e. officially released versions of 135U-Boot will always have a patchlevel of "0". 136 137 138Directory Hierarchy: 139==================== 140 141- board Board dependent files 142- common Misc architecture independent functions 143- cpu CPU specific files 144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 145 - arm720t Files specific to ARM 720 CPUs 146 - arm920t Files specific to ARM 920 CPUs 147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU 148 - imx Files specific to Freescale MC9328 i.MX CPUs 149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs 150 - arm925t Files specific to ARM 925 CPUs 151 - arm926ejs Files specific to ARM 926 CPUs 152 - arm1136 Files specific to ARM 1136 CPUs 153 - at32ap Files specific to Atmel AVR32 AP CPUs 154 - i386 Files specific to i386 CPUs 155 - ixp Files specific to Intel XScale IXP CPUs 156 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 157 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 158 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 159 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 160 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 161 - mips Files specific to MIPS CPUs 162 - mpc5xx Files specific to Freescale MPC5xx CPUs 163 - mpc5xxx Files specific to Freescale MPC5xxx CPUs 164 - mpc8xx Files specific to Freescale MPC8xx CPUs 165 - mpc8220 Files specific to Freescale MPC8220 CPUs 166 - mpc824x Files specific to Freescale MPC824x CPUs 167 - mpc8260 Files specific to Freescale MPC8260 CPUs 168 - mpc85xx Files specific to Freescale MPC85xx CPUs 169 - nios Files specific to Altera NIOS CPUs 170 - nios2 Files specific to Altera Nios-II CPUs 171 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs 172 - pxa Files specific to Intel XScale PXA CPUs 173 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 174 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 175- disk Code for disk drive partition handling 176- doc Documentation (don't expect too much) 177- drivers Commonly used device drivers 178- dtt Digital Thermometer and Thermostat drivers 179- examples Example code for standalone applications, etc. 180- include Header Files 181- lib_arm Files generic to ARM architecture 182- lib_avr32 Files generic to AVR32 architecture 183- lib_generic Files generic to all architectures 184- lib_i386 Files generic to i386 architecture 185- lib_m68k Files generic to m68k architecture 186- lib_mips Files generic to MIPS architecture 187- lib_nios Files generic to NIOS architecture 188- lib_ppc Files generic to PowerPC architecture 189- libfdt Library files to support flattened device trees 190- net Networking code 191- post Power On Self Test 192- rtc Real Time Clock drivers 193- tools Tools to build S-Record or U-Boot images, etc. 194 195Software Configuration: 196======================= 197 198Configuration is usually done using C preprocessor defines; the 199rationale behind that is to avoid dead code whenever possible. 200 201There are two classes of configuration variables: 202 203* Configuration _OPTIONS_: 204 These are selectable by the user and have names beginning with 205 "CONFIG_". 206 207* Configuration _SETTINGS_: 208 These depend on the hardware etc. and should not be meddled with if 209 you don't know what you're doing; they have names beginning with 210 "CFG_". 211 212Later we will add a configuration tool - probably similar to or even 213identical to what's used for the Linux kernel. Right now, we have to 214do the configuration by hand, which means creating some symbolic 215links and editing some configuration files. We use the TQM8xxL boards 216as an example here. 217 218 219Selection of Processor Architecture and Board Type: 220--------------------------------------------------- 221 222For all supported boards there are ready-to-use default 223configurations available; just type "make <board_name>_config". 224 225Example: For a TQM823L module type: 226 227 cd u-boot 228 make TQM823L_config 229 230For the Cogent platform, you need to specify the cpu type as well; 231e.g. "make cogent_mpc8xx_config". And also configure the cogent 232directory according to the instructions in cogent/README. 233 234 235Configuration Options: 236---------------------- 237 238Configuration depends on the combination of board and CPU type; all 239such information is kept in a configuration file 240"include/configs/<board_name>.h". 241 242Example: For a TQM823L module, all configuration settings are in 243"include/configs/TQM823L.h". 244 245 246Many of the options are named exactly as the corresponding Linux 247kernel configuration options. The intention is to make it easier to 248build a config tool - later. 249 250 251The following options need to be configured: 252 253- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 254 255- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 256 257- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 258 Define exactly one, e.g. CONFIG_ATSTK1002 259 260- CPU Module Type: (if CONFIG_COGENT is defined) 261 Define exactly one of 262 CONFIG_CMA286_60_OLD 263--- FIXME --- not tested yet: 264 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 265 CONFIG_CMA287_23, CONFIG_CMA287_50 266 267- Motherboard Type: (if CONFIG_COGENT is defined) 268 Define exactly one of 269 CONFIG_CMA101, CONFIG_CMA102 270 271- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 272 Define one or more of 273 CONFIG_CMA302 274 275- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 276 Define one or more of 277 CONFIG_LCD_HEARTBEAT - update a character position on 278 the lcd display every second with 279 a "rotator" |\-/|\-/ 280 281- Board flavour: (if CONFIG_MPC8260ADS is defined) 282 CONFIG_ADSTYPE 283 Possible values are: 284 CFG_8260ADS - original MPC8260ADS 285 CFG_8266ADS - MPC8266ADS 286 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 287 CFG_8272ADS - MPC8272ADS 288 289- MPC824X Family Member (if CONFIG_MPC824X is defined) 290 Define exactly one of 291 CONFIG_MPC8240, CONFIG_MPC8245 292 293- 8xx CPU Options: (if using an MPC8xx cpu) 294 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 295 get_gclk_freq() cannot work 296 e.g. if there is no 32KHz 297 reference PIT/RTC clock 298 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 299 or XTAL/EXTAL) 300 301- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 302 CFG_8xx_CPUCLK_MIN 303 CFG_8xx_CPUCLK_MAX 304 CONFIG_8xx_CPUCLK_DEFAULT 305 See doc/README.MPC866 306 307 CFG_MEASURE_CPUCLK 308 309 Define this to measure the actual CPU clock instead 310 of relying on the correctness of the configured 311 values. Mostly useful for board bringup to make sure 312 the PLL is locked at the intended frequency. Note 313 that this requires a (stable) reference clock (32 kHz 314 RTC clock or CFG_8XX_XIN) 315 316- Intel Monahans options: 317 CFG_MONAHANS_RUN_MODE_OSC_RATIO 318 319 Defines the Monahans run mode to oscillator 320 ratio. Valid values are 8, 16, 24, 31. The core 321 frequency is this value multiplied by 13 MHz. 322 323 CFG_MONAHANS_TURBO_RUN_MODE_RATIO 324 325 Defines the Monahans turbo mode to oscillator 326 ratio. Valid values are 1 (default if undefined) and 327 2. The core frequency as calculated above is multiplied 328 by this value. 329 330- Linux Kernel Interface: 331 CONFIG_CLOCKS_IN_MHZ 332 333 U-Boot stores all clock information in Hz 334 internally. For binary compatibility with older Linux 335 kernels (which expect the clocks passed in the 336 bd_info data to be in MHz) the environment variable 337 "clocks_in_mhz" can be defined so that U-Boot 338 converts clock data to MHZ before passing it to the 339 Linux kernel. 340 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 341 "clocks_in_mhz=1" is automatically included in the 342 default environment. 343 344 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 345 346 When transfering memsize parameter to linux, some versions 347 expect it to be in bytes, others in MB. 348 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 349 350 CONFIG_OF_LIBFDT / CONFIG_OF_FLAT_TREE 351 352 New kernel versions are expecting firmware settings to be 353 passed using flattened device trees (based on open firmware 354 concepts). 355 356 CONFIG_OF_LIBFDT 357 * New libfdt-based support 358 * Adds the "fdt" command 359 * The bootm command automatically updates the fdt 360 361 CONFIG_OF_FLAT_TREE 362 * Deprecated, see CONFIG_OF_LIBFDT 363 * Original ft_build.c-based support 364 * Automatically modifies the dft as part of the bootm command 365 * The environment variable "disable_of", when set, 366 disables this functionality. 367 368 OF_CPU - The proper name of the cpus node. 369 OF_SOC - The proper name of the soc node. 370 OF_TBCLK - The timebase frequency. 371 OF_STDOUT_PATH - The path to the console device 372 373 boards with QUICC Engines require OF_QE to set UCC mac addresses 374 375 CONFIG_OF_HAS_BD_T 376 377 * CONFIG_OF_LIBFDT - enables the "fdt bd_t" command 378 * CONFIG_OF_FLAT_TREE - The resulting flat device tree 379 will have a copy of the bd_t. Space should be 380 pre-allocated in the dts for the bd_t. 381 382 CONFIG_OF_HAS_UBOOT_ENV 383 384 * CONFIG_OF_LIBFDT - enables the "fdt env" command 385 * CONFIG_OF_FLAT_TREE - The resulting flat device tree 386 will have a copy of u-boot's environment variables 387 388 CONFIG_OF_BOARD_SETUP 389 390 Board code has addition modification that it wants to make 391 to the flat device tree before handing it off to the kernel 392 393 CONFIG_OF_BOOT_CPU 394 395 This define fills in the correct boot cpu in the boot 396 param header, the default value is zero if undefined. 397 398- Serial Ports: 399 CFG_PL010_SERIAL 400 401 Define this if you want support for Amba PrimeCell PL010 UARTs. 402 403 CFG_PL011_SERIAL 404 405 Define this if you want support for Amba PrimeCell PL011 UARTs. 406 407 CONFIG_PL011_CLOCK 408 409 If you have Amba PrimeCell PL011 UARTs, set this variable to 410 the clock speed of the UARTs. 411 412 CONFIG_PL01x_PORTS 413 414 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 415 define this to a list of base addresses for each (supported) 416 port. See e.g. include/configs/versatile.h 417 418 419- Console Interface: 420 Depending on board, define exactly one serial port 421 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 422 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 423 console by defining CONFIG_8xx_CONS_NONE 424 425 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 426 port routines must be defined elsewhere 427 (i.e. serial_init(), serial_getc(), ...) 428 429 CONFIG_CFB_CONSOLE 430 Enables console device for a color framebuffer. Needs following 431 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 432 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 433 (default big endian) 434 VIDEO_HW_RECTFILL graphic chip supports 435 rectangle fill 436 (cf. smiLynxEM) 437 VIDEO_HW_BITBLT graphic chip supports 438 bit-blit (cf. smiLynxEM) 439 VIDEO_VISIBLE_COLS visible pixel columns 440 (cols=pitch) 441 VIDEO_VISIBLE_ROWS visible pixel rows 442 VIDEO_PIXEL_SIZE bytes per pixel 443 VIDEO_DATA_FORMAT graphic data format 444 (0-5, cf. cfb_console.c) 445 VIDEO_FB_ADRS framebuffer address 446 VIDEO_KBD_INIT_FCT keyboard int fct 447 (i.e. i8042_kbd_init()) 448 VIDEO_TSTC_FCT test char fct 449 (i.e. i8042_tstc) 450 VIDEO_GETC_FCT get char fct 451 (i.e. i8042_getc) 452 CONFIG_CONSOLE_CURSOR cursor drawing on/off 453 (requires blink timer 454 cf. i8042.c) 455 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 456 CONFIG_CONSOLE_TIME display time/date info in 457 upper right corner 458 (requires CONFIG_CMD_DATE) 459 CONFIG_VIDEO_LOGO display Linux logo in 460 upper left corner 461 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 462 linux_logo.h for logo. 463 Requires CONFIG_VIDEO_LOGO 464 CONFIG_CONSOLE_EXTRA_INFO 465 addional board info beside 466 the logo 467 468 When CONFIG_CFB_CONSOLE is defined, video console is 469 default i/o. Serial console can be forced with 470 environment 'console=serial'. 471 472 When CONFIG_SILENT_CONSOLE is defined, all console 473 messages (by U-Boot and Linux!) can be silenced with 474 the "silent" environment variable. See 475 doc/README.silent for more information. 476 477- Console Baudrate: 478 CONFIG_BAUDRATE - in bps 479 Select one of the baudrates listed in 480 CFG_BAUDRATE_TABLE, see below. 481 CFG_BRGCLK_PRESCALE, baudrate prescale 482 483- Interrupt driven serial port input: 484 CONFIG_SERIAL_SOFTWARE_FIFO 485 486 PPC405GP only. 487 Use an interrupt handler for receiving data on the 488 serial port. It also enables using hardware handshake 489 (RTS/CTS) and UART's built-in FIFO. Set the number of 490 bytes the interrupt driven input buffer should have. 491 492 Leave undefined to disable this feature, including 493 disable the buffer and hardware handshake. 494 495- Console UART Number: 496 CONFIG_UART1_CONSOLE 497 498 AMCC PPC4xx only. 499 If defined internal UART1 (and not UART0) is used 500 as default U-Boot console. 501 502- Boot Delay: CONFIG_BOOTDELAY - in seconds 503 Delay before automatically booting the default image; 504 set to -1 to disable autoboot. 505 506 See doc/README.autoboot for these options that 507 work with CONFIG_BOOTDELAY. None are required. 508 CONFIG_BOOT_RETRY_TIME 509 CONFIG_BOOT_RETRY_MIN 510 CONFIG_AUTOBOOT_KEYED 511 CONFIG_AUTOBOOT_PROMPT 512 CONFIG_AUTOBOOT_DELAY_STR 513 CONFIG_AUTOBOOT_STOP_STR 514 CONFIG_AUTOBOOT_DELAY_STR2 515 CONFIG_AUTOBOOT_STOP_STR2 516 CONFIG_ZERO_BOOTDELAY_CHECK 517 CONFIG_RESET_TO_RETRY 518 519- Autoboot Command: 520 CONFIG_BOOTCOMMAND 521 Only needed when CONFIG_BOOTDELAY is enabled; 522 define a command string that is automatically executed 523 when no character is read on the console interface 524 within "Boot Delay" after reset. 525 526 CONFIG_BOOTARGS 527 This can be used to pass arguments to the bootm 528 command. The value of CONFIG_BOOTARGS goes into the 529 environment value "bootargs". 530 531 CONFIG_RAMBOOT and CONFIG_NFSBOOT 532 The value of these goes into the environment as 533 "ramboot" and "nfsboot" respectively, and can be used 534 as a convenience, when switching between booting from 535 ram and nfs. 536 537- Pre-Boot Commands: 538 CONFIG_PREBOOT 539 540 When this option is #defined, the existence of the 541 environment variable "preboot" will be checked 542 immediately before starting the CONFIG_BOOTDELAY 543 countdown and/or running the auto-boot command resp. 544 entering interactive mode. 545 546 This feature is especially useful when "preboot" is 547 automatically generated or modified. For an example 548 see the LWMON board specific code: here "preboot" is 549 modified when the user holds down a certain 550 combination of keys on the (special) keyboard when 551 booting the systems 552 553- Serial Download Echo Mode: 554 CONFIG_LOADS_ECHO 555 If defined to 1, all characters received during a 556 serial download (using the "loads" command) are 557 echoed back. This might be needed by some terminal 558 emulations (like "cu"), but may as well just take 559 time on others. This setting #define's the initial 560 value of the "loads_echo" environment variable. 561 562- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 563 CONFIG_KGDB_BAUDRATE 564 Select one of the baudrates listed in 565 CFG_BAUDRATE_TABLE, see below. 566 567- Monitor Functions: 568 Monitor commands can be included or excluded 569 from the build by using the #include files 570 "config_cmd_all.h" and #undef'ing unwanted 571 commands, or using "config_cmd_default.h" 572 and augmenting with additional #define's 573 for wanted commands. 574 575 The default command configuration includes all commands 576 except those marked below with a "*". 577 578 CONFIG_CMD_ASKENV * ask for env variable 579 CONFIG_CMD_AUTOSCRIPT Autoscript Support 580 CONFIG_CMD_BDI bdinfo 581 CONFIG_CMD_BEDBUG * Include BedBug Debugger 582 CONFIG_CMD_BMP * BMP support 583 CONFIG_CMD_BSP * Board specific commands 584 CONFIG_CMD_BOOTD bootd 585 CONFIG_CMD_CACHE * icache, dcache 586 CONFIG_CMD_CONSOLE coninfo 587 CONFIG_CMD_DATE * support for RTC, date/time... 588 CONFIG_CMD_DHCP * DHCP support 589 CONFIG_CMD_DIAG * Diagnostics 590 CONFIG_CMD_DOC * Disk-On-Chip Support 591 CONFIG_CMD_DTT * Digital Therm and Thermostat 592 CONFIG_CMD_ECHO echo arguments 593 CONFIG_CMD_EEPROM * EEPROM read/write support 594 CONFIG_CMD_ELF * bootelf, bootvx 595 CONFIG_CMD_ENV saveenv 596 CONFIG_CMD_FDC * Floppy Disk Support 597 CONFIG_CMD_FAT * FAT partition support 598 CONFIG_CMD_FDOS * Dos diskette Support 599 CONFIG_CMD_FLASH flinfo, erase, protect 600 CONFIG_CMD_FPGA FPGA device initialization support 601 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 602 CONFIG_CMD_I2C * I2C serial bus support 603 CONFIG_CMD_IDE * IDE harddisk support 604 CONFIG_CMD_IMI iminfo 605 CONFIG_CMD_IMLS List all found images 606 CONFIG_CMD_IMMAP * IMMR dump support 607 CONFIG_CMD_IRQ * irqinfo 608 CONFIG_CMD_ITEST Integer/string test of 2 values 609 CONFIG_CMD_JFFS2 * JFFS2 Support 610 CONFIG_CMD_KGDB * kgdb 611 CONFIG_CMD_LOADB loadb 612 CONFIG_CMD_LOADS loads 613 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 614 loop, loopw, mtest 615 CONFIG_CMD_MISC Misc functions like sleep etc 616 CONFIG_CMD_MMC * MMC memory mapped support 617 CONFIG_CMD_MII * MII utility commands 618 CONFIG_CMD_NAND * NAND support 619 CONFIG_CMD_NET bootp, tftpboot, rarpboot 620 CONFIG_CMD_PCI * pciinfo 621 CONFIG_CMD_PCMCIA * PCMCIA support 622 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 623 host 624 CONFIG_CMD_PORTIO * Port I/O 625 CONFIG_CMD_REGINFO * Register dump 626 CONFIG_CMD_RUN run command in env variable 627 CONFIG_CMD_SAVES * save S record dump 628 CONFIG_CMD_SCSI * SCSI Support 629 CONFIG_CMD_SDRAM * print SDRAM configuration information 630 (requires CONFIG_CMD_I2C) 631 CONFIG_CMD_SETGETDCR Support for DCR Register access 632 (4xx only) 633 CONFIG_CMD_SPI * SPI serial bus support 634 CONFIG_CMD_USB * USB support 635 CONFIG_CMD_VFD * VFD support (TRAB) 636 CONFIG_CMD_BSP * Board SPecific functions 637 CONFIG_CMD_CDP * Cisco Discover Protocol support 638 CONFIG_CMD_FSL * Microblaze FSL support 639 640 641 EXAMPLE: If you want all functions except of network 642 support you can write: 643 644 #include "config_cmd_all.h" 645 #undef CONFIG_CMD_NET 646 647 Other Commands: 648 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 649 650 Note: Don't enable the "icache" and "dcache" commands 651 (configuration option CONFIG_CMD_CACHE) unless you know 652 what you (and your U-Boot users) are doing. Data 653 cache cannot be enabled on systems like the 8xx or 654 8260 (where accesses to the IMMR region must be 655 uncached), and it cannot be disabled on all other 656 systems where we (mis-) use the data cache to hold an 657 initial stack and some data. 658 659 660 XXX - this list needs to get updated! 661 662- Watchdog: 663 CONFIG_WATCHDOG 664 If this variable is defined, it enables watchdog 665 support. There must be support in the platform specific 666 code for a watchdog. For the 8xx and 8260 CPUs, the 667 SIU Watchdog feature is enabled in the SYPCR 668 register. 669 670- U-Boot Version: 671 CONFIG_VERSION_VARIABLE 672 If this variable is defined, an environment variable 673 named "ver" is created by U-Boot showing the U-Boot 674 version as printed by the "version" command. 675 This variable is readonly. 676 677- Real-Time Clock: 678 679 When CONFIG_CMD_DATE is selected, the type of the RTC 680 has to be selected, too. Define exactly one of the 681 following options: 682 683 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 684 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 685 CONFIG_RTC_MC146818 - use MC146818 RTC 686 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 687 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 688 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 689 CONFIG_RTC_DS164x - use Dallas DS164x RTC 690 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 691 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 692 CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 693 694 Note that if the RTC uses I2C, then the I2C interface 695 must also be configured. See I2C Support, below. 696 697- Timestamp Support: 698 699 When CONFIG_TIMESTAMP is selected, the timestamp 700 (date and time) of an image is printed by image 701 commands like bootm or iminfo. This option is 702 automatically enabled when you select CONFIG_CMD_DATE . 703 704- Partition Support: 705 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 706 and/or CONFIG_ISO_PARTITION 707 708 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 709 CONFIG_CMD_SCSI) you must configure support for at 710 least one partition type as well. 711 712- IDE Reset method: 713 CONFIG_IDE_RESET_ROUTINE - this is defined in several 714 board configurations files but used nowhere! 715 716 CONFIG_IDE_RESET - is this is defined, IDE Reset will 717 be performed by calling the function 718 ide_set_reset(int reset) 719 which has to be defined in a board specific file 720 721- ATAPI Support: 722 CONFIG_ATAPI 723 724 Set this to enable ATAPI support. 725 726- LBA48 Support 727 CONFIG_LBA48 728 729 Set this to enable support for disks larger than 137GB 730 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 731 Whithout these , LBA48 support uses 32bit variables and will 'only' 732 support disks up to 2.1TB. 733 734 CFG_64BIT_LBA: 735 When enabled, makes the IDE subsystem use 64bit sector addresses. 736 Default is 32bit. 737 738- SCSI Support: 739 At the moment only there is only support for the 740 SYM53C8XX SCSI controller; define 741 CONFIG_SCSI_SYM53C8XX to enable it. 742 743 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 744 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 745 CFG_SCSI_MAX_LUN] can be adjusted to define the 746 maximum numbers of LUNs, SCSI ID's and target 747 devices. 748 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 749 750- NETWORK Support (PCI): 751 CONFIG_E1000 752 Support for Intel 8254x gigabit chips. 753 754 CONFIG_E1000_FALLBACK_MAC 755 default MAC for empty eeprom after production. 756 757 CONFIG_EEPRO100 758 Support for Intel 82557/82559/82559ER chips. 759 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 760 write routine for first time initialisation. 761 762 CONFIG_TULIP 763 Support for Digital 2114x chips. 764 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 765 modem chip initialisation (KS8761/QS6611). 766 767 CONFIG_NATSEMI 768 Support for National dp83815 chips. 769 770 CONFIG_NS8382X 771 Support for National dp8382[01] gigabit chips. 772 773- NETWORK Support (other): 774 775 CONFIG_DRIVER_LAN91C96 776 Support for SMSC's LAN91C96 chips. 777 778 CONFIG_LAN91C96_BASE 779 Define this to hold the physical address 780 of the LAN91C96's I/O space 781 782 CONFIG_LAN91C96_USE_32_BIT 783 Define this to enable 32 bit addressing 784 785 CONFIG_DRIVER_SMC91111 786 Support for SMSC's LAN91C111 chip 787 788 CONFIG_SMC91111_BASE 789 Define this to hold the physical address 790 of the device (I/O space) 791 792 CONFIG_SMC_USE_32_BIT 793 Define this if data bus is 32 bits 794 795 CONFIG_SMC_USE_IOFUNCS 796 Define this to use i/o functions instead of macros 797 (some hardware wont work with macros) 798 799- USB Support: 800 At the moment only the UHCI host controller is 801 supported (PIP405, MIP405, MPC5200); define 802 CONFIG_USB_UHCI to enable it. 803 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 804 and define CONFIG_USB_STORAGE to enable the USB 805 storage devices. 806 Note: 807 Supported are USB Keyboards and USB Floppy drives 808 (TEAC FD-05PUB). 809 MPC5200 USB requires additional defines: 810 CONFIG_USB_CLOCK 811 for 528 MHz Clock: 0x0001bbbb 812 CONFIG_USB_CONFIG 813 for differential drivers: 0x00001000 814 for single ended drivers: 0x00005000 815 CFG_USB_EVENT_POLL 816 May be defined to allow interrupt polling 817 instead of using asynchronous interrupts 818 819- USB Device: 820 Define the below if you wish to use the USB console. 821 Once firmware is rebuilt from a serial console issue the 822 command "setenv stdin usbtty; setenv stdout usbtty" and 823 attach your usb cable. The Unix command "dmesg" should print 824 it has found a new device. The environment variable usbtty 825 can be set to gserial or cdc_acm to enable your device to 826 appear to a USB host as a Linux gserial device or a 827 Common Device Class Abstract Control Model serial device. 828 If you select usbtty = gserial you should be able to enumerate 829 a Linux host by 830 # modprobe usbserial vendor=0xVendorID product=0xProductID 831 else if using cdc_acm, simply setting the environment 832 variable usbtty to be cdc_acm should suffice. The following 833 might be defined in YourBoardName.h 834 835 CONFIG_USB_DEVICE 836 Define this to build a UDC device 837 838 CONFIG_USB_TTY 839 Define this to have a tty type of device available to 840 talk to the UDC device 841 842 CFG_CONSOLE_IS_IN_ENV 843 Define this if you want stdin, stdout &/or stderr to 844 be set to usbtty. 845 846 mpc8xx: 847 CFG_USB_EXTC_CLK 0xBLAH 848 Derive USB clock from external clock "blah" 849 - CFG_USB_EXTC_CLK 0x02 850 851 CFG_USB_BRG_CLK 0xBLAH 852 Derive USB clock from brgclk 853 - CFG_USB_BRG_CLK 0x04 854 855 If you have a USB-IF assigned VendorID then you may wish to 856 define your own vendor specific values either in BoardName.h 857 or directly in usbd_vendor_info.h. If you don't define 858 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 859 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 860 should pretend to be a Linux device to it's target host. 861 862 CONFIG_USBD_MANUFACTURER 863 Define this string as the name of your company for 864 - CONFIG_USBD_MANUFACTURER "my company" 865 866 CONFIG_USBD_PRODUCT_NAME 867 Define this string as the name of your product 868 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 869 870 CONFIG_USBD_VENDORID 871 Define this as your assigned Vendor ID from the USB 872 Implementors Forum. This *must* be a genuine Vendor ID 873 to avoid polluting the USB namespace. 874 - CONFIG_USBD_VENDORID 0xFFFF 875 876 CONFIG_USBD_PRODUCTID 877 Define this as the unique Product ID 878 for your device 879 - CONFIG_USBD_PRODUCTID 0xFFFF 880 881 882- MMC Support: 883 The MMC controller on the Intel PXA is supported. To 884 enable this define CONFIG_MMC. The MMC can be 885 accessed from the boot prompt by mapping the device 886 to physical memory similar to flash. Command line is 887 enabled with CONFIG_CMD_MMC. The MMC driver also works with 888 the FAT fs. This is enabled with CONFIG_CMD_FAT. 889 890- Journaling Flash filesystem support: 891 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 892 CONFIG_JFFS2_NAND_DEV 893 Define these for a default partition on a NAND device 894 895 CFG_JFFS2_FIRST_SECTOR, 896 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 897 Define these for a default partition on a NOR device 898 899 CFG_JFFS_CUSTOM_PART 900 Define this to create an own partition. You have to provide a 901 function struct part_info* jffs2_part_info(int part_num) 902 903 If you define only one JFFS2 partition you may also want to 904 #define CFG_JFFS_SINGLE_PART 1 905 to disable the command chpart. This is the default when you 906 have not defined a custom partition 907 908- Keyboard Support: 909 CONFIG_ISA_KEYBOARD 910 911 Define this to enable standard (PC-Style) keyboard 912 support 913 914 CONFIG_I8042_KBD 915 Standard PC keyboard driver with US (is default) and 916 GERMAN key layout (switch via environment 'keymap=de') support. 917 Export function i8042_kbd_init, i8042_tstc and i8042_getc 918 for cfb_console. Supports cursor blinking. 919 920- Video support: 921 CONFIG_VIDEO 922 923 Define this to enable video support (for output to 924 video). 925 926 CONFIG_VIDEO_CT69000 927 928 Enable Chips & Technologies 69000 Video chip 929 930 CONFIG_VIDEO_SMI_LYNXEM 931 Enable Silicon Motion SMI 712/710/810 Video chip. The 932 video output is selected via environment 'videoout' 933 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 934 assumed. 935 936 For the CT69000 and SMI_LYNXEM drivers, videomode is 937 selected via environment 'videomode'. Two diferent ways 938 are possible: 939 - "videomode=num" 'num' is a standard LiLo mode numbers. 940 Following standard modes are supported (* is default): 941 942 Colors 640x480 800x600 1024x768 1152x864 1280x1024 943 -------------+--------------------------------------------- 944 8 bits | 0x301* 0x303 0x305 0x161 0x307 945 15 bits | 0x310 0x313 0x316 0x162 0x319 946 16 bits | 0x311 0x314 0x317 0x163 0x31A 947 24 bits | 0x312 0x315 0x318 ? 0x31B 948 -------------+--------------------------------------------- 949 (i.e. setenv videomode 317; saveenv; reset;) 950 951 - "videomode=bootargs" all the video parameters are parsed 952 from the bootargs. (See drivers/video/videomodes.c) 953 954 955 CONFIG_VIDEO_SED13806 956 Enable Epson SED13806 driver. This driver supports 8bpp 957 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 958 or CONFIG_VIDEO_SED13806_16BPP 959 960- Keyboard Support: 961 CONFIG_KEYBOARD 962 963 Define this to enable a custom keyboard support. 964 This simply calls drv_keyboard_init() which must be 965 defined in your board-specific files. 966 The only board using this so far is RBC823. 967 968- LCD Support: CONFIG_LCD 969 970 Define this to enable LCD support (for output to LCD 971 display); also select one of the supported displays 972 by defining one of these: 973 974 CONFIG_NEC_NL6448AC33: 975 976 NEC NL6448AC33-18. Active, color, single scan. 977 978 CONFIG_NEC_NL6448BC20 979 980 NEC NL6448BC20-08. 6.5", 640x480. 981 Active, color, single scan. 982 983 CONFIG_NEC_NL6448BC33_54 984 985 NEC NL6448BC33-54. 10.4", 640x480. 986 Active, color, single scan. 987 988 CONFIG_SHARP_16x9 989 990 Sharp 320x240. Active, color, single scan. 991 It isn't 16x9, and I am not sure what it is. 992 993 CONFIG_SHARP_LQ64D341 994 995 Sharp LQ64D341 display, 640x480. 996 Active, color, single scan. 997 998 CONFIG_HLD1045 999 1000 HLD1045 display, 640x480. 1001 Active, color, single scan. 1002 1003 CONFIG_OPTREX_BW 1004 1005 Optrex CBL50840-2 NF-FW 99 22 M5 1006 or 1007 Hitachi LMG6912RPFC-00T 1008 or 1009 Hitachi SP14Q002 1010 1011 320x240. Black & white. 1012 1013 Normally display is black on white background; define 1014 CFG_WHITE_ON_BLACK to get it inverted. 1015 1016- Splash Screen Support: CONFIG_SPLASH_SCREEN 1017 1018 If this option is set, the environment is checked for 1019 a variable "splashimage". If found, the usual display 1020 of logo, copyright and system information on the LCD 1021 is suppressed and the BMP image at the address 1022 specified in "splashimage" is loaded instead. The 1023 console is redirected to the "nulldev", too. This 1024 allows for a "silent" boot where a splash screen is 1025 loaded very quickly after power-on. 1026 1027- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1028 1029 If this option is set, additionally to standard BMP 1030 images, gzipped BMP images can be displayed via the 1031 splashscreen support or the bmp command. 1032 1033- Compression support: 1034 CONFIG_BZIP2 1035 1036 If this option is set, support for bzip2 compressed 1037 images is included. If not, only uncompressed and gzip 1038 compressed images are supported. 1039 1040 NOTE: the bzip2 algorithm requires a lot of RAM, so 1041 the malloc area (as defined by CFG_MALLOC_LEN) should 1042 be at least 4MB. 1043 1044- MII/PHY support: 1045 CONFIG_PHY_ADDR 1046 1047 The address of PHY on MII bus. 1048 1049 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1050 1051 The clock frequency of the MII bus 1052 1053 CONFIG_PHY_GIGE 1054 1055 If this option is set, support for speed/duplex 1056 detection of Gigabit PHY is included. 1057 1058 CONFIG_PHY_RESET_DELAY 1059 1060 Some PHY like Intel LXT971A need extra delay after 1061 reset before any MII register access is possible. 1062 For such PHY, set this option to the usec delay 1063 required. (minimum 300usec for LXT971A) 1064 1065 CONFIG_PHY_CMD_DELAY (ppc4xx) 1066 1067 Some PHY like Intel LXT971A need extra delay after 1068 command issued before MII status register can be read 1069 1070- Ethernet address: 1071 CONFIG_ETHADDR 1072 CONFIG_ETH2ADDR 1073 CONFIG_ETH3ADDR 1074 1075 Define a default value for ethernet address to use 1076 for the respective ethernet interface, in case this 1077 is not determined automatically. 1078 1079- IP address: 1080 CONFIG_IPADDR 1081 1082 Define a default value for the IP address to use for 1083 the default ethernet interface, in case this is not 1084 determined through e.g. bootp. 1085 1086- Server IP address: 1087 CONFIG_SERVERIP 1088 1089 Defines a default value for theIP address of a TFTP 1090 server to contact when using the "tftboot" command. 1091 1092- Multicast TFTP Mode: 1093 CONFIG_MCAST_TFTP 1094 1095 Defines whether you want to support multicast TFTP as per 1096 rfc-2090; for example to work with atftp. Lets lots of targets 1097 tftp down the same boot image concurrently. Note: the ethernet 1098 driver in use must provide a function: mcast() to join/leave a 1099 multicast group. 1100 1101 CONFIG_BOOTP_RANDOM_DELAY 1102- BOOTP Recovery Mode: 1103 CONFIG_BOOTP_RANDOM_DELAY 1104 1105 If you have many targets in a network that try to 1106 boot using BOOTP, you may want to avoid that all 1107 systems send out BOOTP requests at precisely the same 1108 moment (which would happen for instance at recovery 1109 from a power failure, when all systems will try to 1110 boot, thus flooding the BOOTP server. Defining 1111 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1112 inserted before sending out BOOTP requests. The 1113 following delays are inserted then: 1114 1115 1st BOOTP request: delay 0 ... 1 sec 1116 2nd BOOTP request: delay 0 ... 2 sec 1117 3rd BOOTP request: delay 0 ... 4 sec 1118 4th and following 1119 BOOTP requests: delay 0 ... 8 sec 1120 1121- DHCP Advanced Options: 1122 You can fine tune the DHCP functionality by defining 1123 CONFIG_BOOTP_* symbols: 1124 1125 CONFIG_BOOTP_SUBNETMASK 1126 CONFIG_BOOTP_GATEWAY 1127 CONFIG_BOOTP_HOSTNAME 1128 CONFIG_BOOTP_NISDOMAIN 1129 CONFIG_BOOTP_BOOTPATH 1130 CONFIG_BOOTP_BOOTFILESIZE 1131 CONFIG_BOOTP_DNS 1132 CONFIG_BOOTP_DNS2 1133 CONFIG_BOOTP_SEND_HOSTNAME 1134 CONFIG_BOOTP_NTPSERVER 1135 CONFIG_BOOTP_TIMEOFFSET 1136 CONFIG_BOOTP_VENDOREX 1137 1138 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1139 environment variable, not the BOOTP server. 1140 1141 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1142 serverip from a DHCP server, it is possible that more 1143 than one DNS serverip is offered to the client. 1144 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1145 serverip will be stored in the additional environment 1146 variable "dnsip2". The first DNS serverip is always 1147 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1148 is defined. 1149 1150 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1151 to do a dynamic update of a DNS server. To do this, they 1152 need the hostname of the DHCP requester. 1153 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1154 of the "hostname" environment variable is passed as 1155 option 12 to the DHCP server. 1156 1157 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1158 1159 A 32bit value in microseconds for a delay between 1160 receiving a "DHCP Offer" and sending the "DHCP Request". 1161 This fixes a problem with certain DHCP servers that don't 1162 respond 100% of the time to a "DHCP request". E.g. On an 1163 AT91RM9200 processor running at 180MHz, this delay needed 1164 to be *at least* 15,000 usec before a Windows Server 2003 1165 DHCP server would reply 100% of the time. I recommend at 1166 least 50,000 usec to be safe. The alternative is to hope 1167 that one of the retries will be successful but note that 1168 the DHCP timeout and retry process takes a longer than 1169 this delay. 1170 1171 - CDP Options: 1172 CONFIG_CDP_DEVICE_ID 1173 1174 The device id used in CDP trigger frames. 1175 1176 CONFIG_CDP_DEVICE_ID_PREFIX 1177 1178 A two character string which is prefixed to the MAC address 1179 of the device. 1180 1181 CONFIG_CDP_PORT_ID 1182 1183 A printf format string which contains the ascii name of 1184 the port. Normally is set to "eth%d" which sets 1185 eth0 for the first ethernet, eth1 for the second etc. 1186 1187 CONFIG_CDP_CAPABILITIES 1188 1189 A 32bit integer which indicates the device capabilities; 1190 0x00000010 for a normal host which does not forwards. 1191 1192 CONFIG_CDP_VERSION 1193 1194 An ascii string containing the version of the software. 1195 1196 CONFIG_CDP_PLATFORM 1197 1198 An ascii string containing the name of the platform. 1199 1200 CONFIG_CDP_TRIGGER 1201 1202 A 32bit integer sent on the trigger. 1203 1204 CONFIG_CDP_POWER_CONSUMPTION 1205 1206 A 16bit integer containing the power consumption of the 1207 device in .1 of milliwatts. 1208 1209 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1210 1211 A byte containing the id of the VLAN. 1212 1213- Status LED: CONFIG_STATUS_LED 1214 1215 Several configurations allow to display the current 1216 status using a LED. For instance, the LED will blink 1217 fast while running U-Boot code, stop blinking as 1218 soon as a reply to a BOOTP request was received, and 1219 start blinking slow once the Linux kernel is running 1220 (supported by a status LED driver in the Linux 1221 kernel). Defining CONFIG_STATUS_LED enables this 1222 feature in U-Boot. 1223 1224- CAN Support: CONFIG_CAN_DRIVER 1225 1226 Defining CONFIG_CAN_DRIVER enables CAN driver support 1227 on those systems that support this (optional) 1228 feature, like the TQM8xxL modules. 1229 1230- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1231 1232 These enable I2C serial bus commands. Defining either of 1233 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1234 include the appropriate I2C driver for the selected cpu. 1235 1236 This will allow you to use i2c commands at the u-boot 1237 command line (as long as you set CONFIG_CMD_I2C in 1238 CONFIG_COMMANDS) and communicate with i2c based realtime 1239 clock chips. See common/cmd_i2c.c for a description of the 1240 command line interface. 1241 1242 CONFIG_I2C_CMD_TREE is a recommended option that places 1243 all I2C commands under a single 'i2c' root command. The 1244 older 'imm', 'imd', 'iprobe' etc. commands are considered 1245 deprecated and may disappear in the future. 1246 1247 CONFIG_HARD_I2C selects a hardware I2C controller. 1248 1249 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1250 bit-banging) driver instead of CPM or similar hardware 1251 support for I2C. 1252 1253 There are several other quantities that must also be 1254 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1255 1256 In both cases you will need to define CFG_I2C_SPEED 1257 to be the frequency (in Hz) at which you wish your i2c bus 1258 to run and CFG_I2C_SLAVE to be the address of this node (ie 1259 the cpu's i2c node address). 1260 1261 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1262 sets the cpu up as a master node and so its address should 1263 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1264 p.16-473). So, set CFG_I2C_SLAVE to 0. 1265 1266 That's all that's required for CONFIG_HARD_I2C. 1267 1268 If you use the software i2c interface (CONFIG_SOFT_I2C) 1269 then the following macros need to be defined (examples are 1270 from include/configs/lwmon.h): 1271 1272 I2C_INIT 1273 1274 (Optional). Any commands necessary to enable the I2C 1275 controller or configure ports. 1276 1277 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1278 1279 I2C_PORT 1280 1281 (Only for MPC8260 CPU). The I/O port to use (the code 1282 assumes both bits are on the same port). Valid values 1283 are 0..3 for ports A..D. 1284 1285 I2C_ACTIVE 1286 1287 The code necessary to make the I2C data line active 1288 (driven). If the data line is open collector, this 1289 define can be null. 1290 1291 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1292 1293 I2C_TRISTATE 1294 1295 The code necessary to make the I2C data line tri-stated 1296 (inactive). If the data line is open collector, this 1297 define can be null. 1298 1299 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1300 1301 I2C_READ 1302 1303 Code that returns TRUE if the I2C data line is high, 1304 FALSE if it is low. 1305 1306 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1307 1308 I2C_SDA(bit) 1309 1310 If <bit> is TRUE, sets the I2C data line high. If it 1311 is FALSE, it clears it (low). 1312 1313 eg: #define I2C_SDA(bit) \ 1314 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1315 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1316 1317 I2C_SCL(bit) 1318 1319 If <bit> is TRUE, sets the I2C clock line high. If it 1320 is FALSE, it clears it (low). 1321 1322 eg: #define I2C_SCL(bit) \ 1323 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1324 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1325 1326 I2C_DELAY 1327 1328 This delay is invoked four times per clock cycle so this 1329 controls the rate of data transfer. The data rate thus 1330 is 1 / (I2C_DELAY * 4). Often defined to be something 1331 like: 1332 1333 #define I2C_DELAY udelay(2) 1334 1335 CFG_I2C_INIT_BOARD 1336 1337 When a board is reset during an i2c bus transfer 1338 chips might think that the current transfer is still 1339 in progress. On some boards it is possible to access 1340 the i2c SCLK line directly, either by using the 1341 processor pin as a GPIO or by having a second pin 1342 connected to the bus. If this option is defined a 1343 custom i2c_init_board() routine in boards/xxx/board.c 1344 is run early in the boot sequence. 1345 1346 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1347 1348 This option enables configuration of bi_iic_fast[] flags 1349 in u-boot bd_info structure based on u-boot environment 1350 variable "i2cfast". (see also i2cfast) 1351 1352 CONFIG_I2C_MULTI_BUS 1353 1354 This option allows the use of multiple I2C buses, each of which 1355 must have a controller. At any point in time, only one bus is 1356 active. To switch to a different bus, use the 'i2c dev' command. 1357 Note that bus numbering is zero-based. 1358 1359 CFG_I2C_NOPROBES 1360 1361 This option specifies a list of I2C devices that will be skipped 1362 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1363 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1364 pairs. Otherwise, specify a 1D array of device addresses 1365 1366 e.g. 1367 #undef CONFIG_I2C_MULTI_BUS 1368 #define CFG_I2C_NOPROBES {0x50,0x68} 1369 1370 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1371 1372 #define CONFIG_I2C_MULTI_BUS 1373 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1374 1375 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1376 1377 CFG_SPD_BUS_NUM 1378 1379 If defined, then this indicates the I2C bus number for DDR SPD. 1380 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1381 1382 CFG_RTC_BUS_NUM 1383 1384 If defined, then this indicates the I2C bus number for the RTC. 1385 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1386 1387 CFG_DTT_BUS_NUM 1388 1389 If defined, then this indicates the I2C bus number for the DTT. 1390 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1391 1392 CONFIG_FSL_I2C 1393 1394 Define this option if you want to use Freescale's I2C driver in 1395 drivers/i2c/fsl_i2c.c. 1396 1397 1398- SPI Support: CONFIG_SPI 1399 1400 Enables SPI driver (so far only tested with 1401 SPI EEPROM, also an instance works with Crystal A/D and 1402 D/As on the SACSng board) 1403 1404 CONFIG_SPI_X 1405 1406 Enables extended (16-bit) SPI EEPROM addressing. 1407 (symmetrical to CONFIG_I2C_X) 1408 1409 CONFIG_SOFT_SPI 1410 1411 Enables a software (bit-bang) SPI driver rather than 1412 using hardware support. This is a general purpose 1413 driver that only requires three general I/O port pins 1414 (two outputs, one input) to function. If this is 1415 defined, the board configuration must define several 1416 SPI configuration items (port pins to use, etc). For 1417 an example, see include/configs/sacsng.h. 1418 1419 CONFIG_HARD_SPI 1420 1421 Enables a hardware SPI driver for general-purpose reads 1422 and writes. As with CONFIG_SOFT_SPI, the board configuration 1423 must define a list of chip-select function pointers. 1424 Currently supported on some MPC8xxx processors. For an 1425 example, see include/configs/mpc8349emds.h. 1426 1427- FPGA Support: CONFIG_FPGA 1428 1429 Enables FPGA subsystem. 1430 1431 CONFIG_FPGA_<vendor> 1432 1433 Enables support for specific chip vendors. 1434 (ALTERA, XILINX) 1435 1436 CONFIG_FPGA_<family> 1437 1438 Enables support for FPGA family. 1439 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1440 1441 CONFIG_FPGA_COUNT 1442 1443 Specify the number of FPGA devices to support. 1444 1445 CFG_FPGA_PROG_FEEDBACK 1446 1447 Enable printing of hash marks during FPGA configuration. 1448 1449 CFG_FPGA_CHECK_BUSY 1450 1451 Enable checks on FPGA configuration interface busy 1452 status by the configuration function. This option 1453 will require a board or device specific function to 1454 be written. 1455 1456 CONFIG_FPGA_DELAY 1457 1458 If defined, a function that provides delays in the FPGA 1459 configuration driver. 1460 1461 CFG_FPGA_CHECK_CTRLC 1462 Allow Control-C to interrupt FPGA configuration 1463 1464 CFG_FPGA_CHECK_ERROR 1465 1466 Check for configuration errors during FPGA bitfile 1467 loading. For example, abort during Virtex II 1468 configuration if the INIT_B line goes low (which 1469 indicated a CRC error). 1470 1471 CFG_FPGA_WAIT_INIT 1472 1473 Maximum time to wait for the INIT_B line to deassert 1474 after PROB_B has been deasserted during a Virtex II 1475 FPGA configuration sequence. The default time is 500 1476 mS. 1477 1478 CFG_FPGA_WAIT_BUSY 1479 1480 Maximum time to wait for BUSY to deassert during 1481 Virtex II FPGA configuration. The default is 5 mS. 1482 1483 CFG_FPGA_WAIT_CONFIG 1484 1485 Time to wait after FPGA configuration. The default is 1486 200 mS. 1487 1488- Configuration Management: 1489 CONFIG_IDENT_STRING 1490 1491 If defined, this string will be added to the U-Boot 1492 version information (U_BOOT_VERSION) 1493 1494- Vendor Parameter Protection: 1495 1496 U-Boot considers the values of the environment 1497 variables "serial#" (Board Serial Number) and 1498 "ethaddr" (Ethernet Address) to be parameters that 1499 are set once by the board vendor / manufacturer, and 1500 protects these variables from casual modification by 1501 the user. Once set, these variables are read-only, 1502 and write or delete attempts are rejected. You can 1503 change this behviour: 1504 1505 If CONFIG_ENV_OVERWRITE is #defined in your config 1506 file, the write protection for vendor parameters is 1507 completely disabled. Anybody can change or delete 1508 these parameters. 1509 1510 Alternatively, if you #define _both_ CONFIG_ETHADDR 1511 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1512 ethernet address is installed in the environment, 1513 which can be changed exactly ONCE by the user. [The 1514 serial# is unaffected by this, i. e. it remains 1515 read-only.] 1516 1517- Protected RAM: 1518 CONFIG_PRAM 1519 1520 Define this variable to enable the reservation of 1521 "protected RAM", i. e. RAM which is not overwritten 1522 by U-Boot. Define CONFIG_PRAM to hold the number of 1523 kB you want to reserve for pRAM. You can overwrite 1524 this default value by defining an environment 1525 variable "pram" to the number of kB you want to 1526 reserve. Note that the board info structure will 1527 still show the full amount of RAM. If pRAM is 1528 reserved, a new environment variable "mem" will 1529 automatically be defined to hold the amount of 1530 remaining RAM in a form that can be passed as boot 1531 argument to Linux, for instance like that: 1532 1533 setenv bootargs ... mem=\${mem} 1534 saveenv 1535 1536 This way you can tell Linux not to use this memory, 1537 either, which results in a memory region that will 1538 not be affected by reboots. 1539 1540 *WARNING* If your board configuration uses automatic 1541 detection of the RAM size, you must make sure that 1542 this memory test is non-destructive. So far, the 1543 following board configurations are known to be 1544 "pRAM-clean": 1545 1546 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1547 HERMES, IP860, RPXlite, LWMON, LANTEC, 1548 PCU_E, FLAGADM, TQM8260 1549 1550- Error Recovery: 1551 CONFIG_PANIC_HANG 1552 1553 Define this variable to stop the system in case of a 1554 fatal error, so that you have to reset it manually. 1555 This is probably NOT a good idea for an embedded 1556 system where you want to system to reboot 1557 automatically as fast as possible, but it may be 1558 useful during development since you can try to debug 1559 the conditions that lead to the situation. 1560 1561 CONFIG_NET_RETRY_COUNT 1562 1563 This variable defines the number of retries for 1564 network operations like ARP, RARP, TFTP, or BOOTP 1565 before giving up the operation. If not defined, a 1566 default value of 5 is used. 1567 1568- Command Interpreter: 1569 CONFIG_AUTO_COMPLETE 1570 1571 Enable auto completion of commands using TAB. 1572 1573 Note that this feature has NOT been implemented yet 1574 for the "hush" shell. 1575 1576 1577 CFG_HUSH_PARSER 1578 1579 Define this variable to enable the "hush" shell (from 1580 Busybox) as command line interpreter, thus enabling 1581 powerful command line syntax like 1582 if...then...else...fi conditionals or `&&' and '||' 1583 constructs ("shell scripts"). 1584 1585 If undefined, you get the old, much simpler behaviour 1586 with a somewhat smaller memory footprint. 1587 1588 1589 CFG_PROMPT_HUSH_PS2 1590 1591 This defines the secondary prompt string, which is 1592 printed when the command interpreter needs more input 1593 to complete a command. Usually "> ". 1594 1595 Note: 1596 1597 In the current implementation, the local variables 1598 space and global environment variables space are 1599 separated. Local variables are those you define by 1600 simply typing `name=value'. To access a local 1601 variable later on, you have write `$name' or 1602 `${name}'; to execute the contents of a variable 1603 directly type `$name' at the command prompt. 1604 1605 Global environment variables are those you use 1606 setenv/printenv to work with. To run a command stored 1607 in such a variable, you need to use the run command, 1608 and you must not use the '$' sign to access them. 1609 1610 To store commands and special characters in a 1611 variable, please use double quotation marks 1612 surrounding the whole text of the variable, instead 1613 of the backslashes before semicolons and special 1614 symbols. 1615 1616- Commandline Editing and History: 1617 CONFIG_CMDLINE_EDITING 1618 1619 Enable editiong and History functions for interactive 1620 commandline input operations 1621 1622- Default Environment: 1623 CONFIG_EXTRA_ENV_SETTINGS 1624 1625 Define this to contain any number of null terminated 1626 strings (variable = value pairs) that will be part of 1627 the default environment compiled into the boot image. 1628 1629 For example, place something like this in your 1630 board's config file: 1631 1632 #define CONFIG_EXTRA_ENV_SETTINGS \ 1633 "myvar1=value1\0" \ 1634 "myvar2=value2\0" 1635 1636 Warning: This method is based on knowledge about the 1637 internal format how the environment is stored by the 1638 U-Boot code. This is NOT an official, exported 1639 interface! Although it is unlikely that this format 1640 will change soon, there is no guarantee either. 1641 You better know what you are doing here. 1642 1643 Note: overly (ab)use of the default environment is 1644 discouraged. Make sure to check other ways to preset 1645 the environment like the autoscript function or the 1646 boot command first. 1647 1648- DataFlash Support: 1649 CONFIG_HAS_DATAFLASH 1650 1651 Defining this option enables DataFlash features and 1652 allows to read/write in Dataflash via the standard 1653 commands cp, md... 1654 1655- SystemACE Support: 1656 CONFIG_SYSTEMACE 1657 1658 Adding this option adds support for Xilinx SystemACE 1659 chips attached via some sort of local bus. The address 1660 of the chip must alsh be defined in the 1661 CFG_SYSTEMACE_BASE macro. For example: 1662 1663 #define CONFIG_SYSTEMACE 1664 #define CFG_SYSTEMACE_BASE 0xf0000000 1665 1666 When SystemACE support is added, the "ace" device type 1667 becomes available to the fat commands, i.e. fatls. 1668 1669- TFTP Fixed UDP Port: 1670 CONFIG_TFTP_PORT 1671 1672 If this is defined, the environment variable tftpsrcp 1673 is used to supply the TFTP UDP source port value. 1674 If tftpsrcp isn't defined, the normal pseudo-random port 1675 number generator is used. 1676 1677 Also, the environment variable tftpdstp is used to supply 1678 the TFTP UDP destination port value. If tftpdstp isn't 1679 defined, the normal port 69 is used. 1680 1681 The purpose for tftpsrcp is to allow a TFTP server to 1682 blindly start the TFTP transfer using the pre-configured 1683 target IP address and UDP port. This has the effect of 1684 "punching through" the (Windows XP) firewall, allowing 1685 the remainder of the TFTP transfer to proceed normally. 1686 A better solution is to properly configure the firewall, 1687 but sometimes that is not allowed. 1688 1689- Show boot progress: 1690 CONFIG_SHOW_BOOT_PROGRESS 1691 1692 Defining this option allows to add some board- 1693 specific code (calling a user-provided function 1694 "show_boot_progress(int)") that enables you to show 1695 the system's boot progress on some display (for 1696 example, some LED's) on your board. At the moment, 1697 the following checkpoints are implemented: 1698 1699Legacy uImage format: 1700 1701 Arg Where When 1702 1 common/cmd_bootm.c before attempting to boot an image 1703 -1 common/cmd_bootm.c Image header has bad magic number 1704 2 common/cmd_bootm.c Image header has correct magic number 1705 -2 common/cmd_bootm.c Image header has bad checksum 1706 3 common/cmd_bootm.c Image header has correct checksum 1707 -3 common/cmd_bootm.c Image data has bad checksum 1708 4 common/cmd_bootm.c Image data has correct checksum 1709 -4 common/cmd_bootm.c Image is for unsupported architecture 1710 5 common/cmd_bootm.c Architecture check OK 1711 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 1712 6 common/cmd_bootm.c Image Type check OK 1713 -6 common/cmd_bootm.c gunzip uncompression error 1714 -7 common/cmd_bootm.c Unimplemented compression type 1715 7 common/cmd_bootm.c Uncompression OK 1716 8 common/cmd_bootm.c No uncompress/copy overwrite error 1717 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1718 1719 9 common/image.c Start initial ramdisk verification 1720 -10 common/image.c Ramdisk header has bad magic number 1721 -11 common/image.c Ramdisk header has bad checksum 1722 10 common/image.c Ramdisk header is OK 1723 -12 common/image.c Ramdisk data has bad checksum 1724 11 common/image.c Ramdisk data has correct checksum 1725 12 common/image.c Ramdisk verification complete, start loading 1726 -13 common/image.c Wrong Image Type (not PPC Linux Ramdisk) 1727 13 common/image.c Start multifile image verification 1728 14 common/image.c No initial ramdisk, no multifile, continue. 1729 1730 15 lib_<arch>/bootm.c All preparation done, transferring control to OS 1731 1732 -30 lib_ppc/board.c Fatal error, hang the system 1733 -31 post/post.c POST test failed, detected by post_output_backlog() 1734 -32 post/post.c POST test failed, detected by post_run_single() 1735 1736 34 common/cmd_doc.c before loading a Image from a DOC device 1737 -35 common/cmd_doc.c Bad usage of "doc" command 1738 35 common/cmd_doc.c correct usage of "doc" command 1739 -36 common/cmd_doc.c No boot device 1740 36 common/cmd_doc.c correct boot device 1741 -37 common/cmd_doc.c Unknown Chip ID on boot device 1742 37 common/cmd_doc.c correct chip ID found, device available 1743 -38 common/cmd_doc.c Read Error on boot device 1744 38 common/cmd_doc.c reading Image header from DOC device OK 1745 -39 common/cmd_doc.c Image header has bad magic number 1746 39 common/cmd_doc.c Image header has correct magic number 1747 -40 common/cmd_doc.c Error reading Image from DOC device 1748 40 common/cmd_doc.c Image header has correct magic number 1749 41 common/cmd_ide.c before loading a Image from a IDE device 1750 -42 common/cmd_ide.c Bad usage of "ide" command 1751 42 common/cmd_ide.c correct usage of "ide" command 1752 -43 common/cmd_ide.c No boot device 1753 43 common/cmd_ide.c boot device found 1754 -44 common/cmd_ide.c Device not available 1755 44 common/cmd_ide.c Device available 1756 -45 common/cmd_ide.c wrong partition selected 1757 45 common/cmd_ide.c partition selected 1758 -46 common/cmd_ide.c Unknown partition table 1759 46 common/cmd_ide.c valid partition table found 1760 -47 common/cmd_ide.c Invalid partition type 1761 47 common/cmd_ide.c correct partition type 1762 -48 common/cmd_ide.c Error reading Image Header on boot device 1763 48 common/cmd_ide.c reading Image Header from IDE device OK 1764 -49 common/cmd_ide.c Image header has bad magic number 1765 49 common/cmd_ide.c Image header has correct magic number 1766 -50 common/cmd_ide.c Image header has bad checksum 1767 50 common/cmd_ide.c Image header has correct checksum 1768 -51 common/cmd_ide.c Error reading Image from IDE device 1769 51 common/cmd_ide.c reading Image from IDE device OK 1770 52 common/cmd_nand.c before loading a Image from a NAND device 1771 -53 common/cmd_nand.c Bad usage of "nand" command 1772 53 common/cmd_nand.c correct usage of "nand" command 1773 -54 common/cmd_nand.c No boot device 1774 54 common/cmd_nand.c boot device found 1775 -55 common/cmd_nand.c Unknown Chip ID on boot device 1776 55 common/cmd_nand.c correct chip ID found, device available 1777 -56 common/cmd_nand.c Error reading Image Header on boot device 1778 56 common/cmd_nand.c reading Image Header from NAND device OK 1779 -57 common/cmd_nand.c Image header has bad magic number 1780 57 common/cmd_nand.c Image header has correct magic number 1781 -58 common/cmd_nand.c Error reading Image from NAND device 1782 58 common/cmd_nand.c reading Image from NAND device OK 1783 1784 -60 common/env_common.c Environment has a bad CRC, using default 1785 1786 64 net/eth.c starting with Ethernetconfiguration. 1787 -64 net/eth.c no Ethernet found. 1788 65 net/eth.c Ethernet found. 1789 1790 -80 common/cmd_net.c usage wrong 1791 80 common/cmd_net.c before calling NetLoop() 1792 -81 common/cmd_net.c some error in NetLoop() occured 1793 81 common/cmd_net.c NetLoop() back without error 1794 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1795 82 common/cmd_net.c trying automatic boot 1796 83 common/cmd_net.c running autoscript 1797 -83 common/cmd_net.c some error in automatic boot or autoscript 1798 84 common/cmd_net.c end without errors 1799 1800FIT uImage format: 1801 1802 Arg Where When 1803 100 common/cmd_bootm.c Kernel FIT Image has correct format 1804 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 1805 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 1806 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 1807 102 common/cmd_bootm.c Kernel unit name specified 1808 -103 common/cmd_bootm.c Can't get kernel subimage node offset 1809 103 common/cmd_bootm.c Found configuration node 1810 104 common/cmd_bootm.c Got kernel subimage node offset 1811 -104 common/cmd_bootm.c Kernel subimage hash verification failed 1812 105 common/cmd_bootm.c Kernel subimage hash verification OK 1813 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 1814 106 common/cmd_bootm.c Architecture check OK 1815 -106 common/cmd_bootm.c Kernel subimage has wrong typea 1816 107 common/cmd_bootm.c Kernel subimge type OK 1817 -107 common/cmd_bootm.c Can't get kernel subimage data/size 1818 108 common/cmd_bootm.c Got kernel subimage data/size 1819 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 1820 -109 common/cmd_bootm.c Can't get kernel subimage type 1821 -110 common/cmd_bootm.c Can't get kernel subimage comp 1822 -111 common/cmd_bootm.c Can't get kernel subimage os 1823 -112 common/cmd_bootm.c Can't get kernel subimage load address 1824 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 1825 1826 120 common/image.c Start initial ramdisk verification 1827 -120 common/image.c Ramdisk FIT image has incorrect format 1828 121 common/image.c Ramdisk FIT image has correct format 1829 122 common/image.c No Ramdisk subimage unit name, using configuration 1830 -122 common/image.c Can't get configuration for ramdisk subimage 1831 123 common/image.c Ramdisk unit name specified 1832 -124 common/image.c Can't get ramdisk subimage node offset 1833 125 common/image.c Got ramdisk subimage node offset 1834 -125 common/image.c Ramdisk subimage hash verification failed 1835 126 common/image.c Ramdisk subimage hash verification OK 1836 -126 common/image.c Ramdisk subimage for unsupported architecture 1837 127 common/image.c Architecture check OK 1838 -127 common/image.c Can't get ramdisk subimage data/size 1839 128 common/image.c Got ramdisk subimage data/size 1840 129 common/image.c Can't get ramdisk load address 1841 -129 common/image.c Got ramdisk load address 1842 1843 -130 common/cmd_doc.c Icorrect FIT image format 1844 131 common/cmd_doc.c FIT image format OK 1845 1846 -140 common/cmd_ide.c Icorrect FIT image format 1847 141 common/cmd_ide.c FIT image format OK 1848 1849 -150 common/cmd_nand.c Icorrect FIT image format 1850 151 common/cmd_nand.c FIT image format OK 1851 1852 1853Modem Support: 1854-------------- 1855 1856[so far only for SMDK2400 and TRAB boards] 1857 1858- Modem support endable: 1859 CONFIG_MODEM_SUPPORT 1860 1861- RTS/CTS Flow control enable: 1862 CONFIG_HWFLOW 1863 1864- Modem debug support: 1865 CONFIG_MODEM_SUPPORT_DEBUG 1866 1867 Enables debugging stuff (char screen[1024], dbg()) 1868 for modem support. Useful only with BDI2000. 1869 1870- Interrupt support (PPC): 1871 1872 There are common interrupt_init() and timer_interrupt() 1873 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1874 for cpu specific initialization. interrupt_init_cpu() 1875 should set decrementer_count to appropriate value. If 1876 cpu resets decrementer automatically after interrupt 1877 (ppc4xx) it should set decrementer_count to zero. 1878 timer_interrupt() calls timer_interrupt_cpu() for cpu 1879 specific handling. If board has watchdog / status_led 1880 / other_activity_monitor it works automatically from 1881 general timer_interrupt(). 1882 1883- General: 1884 1885 In the target system modem support is enabled when a 1886 specific key (key combination) is pressed during 1887 power-on. Otherwise U-Boot will boot normally 1888 (autoboot). The key_pressed() fuction is called from 1889 board_init(). Currently key_pressed() is a dummy 1890 function, returning 1 and thus enabling modem 1891 initialization. 1892 1893 If there are no modem init strings in the 1894 environment, U-Boot proceed to autoboot; the 1895 previous output (banner, info printfs) will be 1896 supressed, though. 1897 1898 See also: doc/README.Modem 1899 1900 1901Configuration Settings: 1902----------------------- 1903 1904- CFG_LONGHELP: Defined when you want long help messages included; 1905 undefine this when you're short of memory. 1906 1907- CFG_PROMPT: This is what U-Boot prints on the console to 1908 prompt for user input. 1909 1910- CFG_CBSIZE: Buffer size for input from the Console 1911 1912- CFG_PBSIZE: Buffer size for Console output 1913 1914- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1915 1916- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1917 the application (usually a Linux kernel) when it is 1918 booted 1919 1920- CFG_BAUDRATE_TABLE: 1921 List of legal baudrate settings for this board. 1922 1923- CFG_CONSOLE_INFO_QUIET 1924 Suppress display of console information at boot. 1925 1926- CFG_CONSOLE_IS_IN_ENV 1927 If the board specific function 1928 extern int overwrite_console (void); 1929 returns 1, the stdin, stderr and stdout are switched to the 1930 serial port, else the settings in the environment are used. 1931 1932- CFG_CONSOLE_OVERWRITE_ROUTINE 1933 Enable the call to overwrite_console(). 1934 1935- CFG_CONSOLE_ENV_OVERWRITE 1936 Enable overwrite of previous console environment settings. 1937 1938- CFG_MEMTEST_START, CFG_MEMTEST_END: 1939 Begin and End addresses of the area used by the 1940 simple memory test. 1941 1942- CFG_ALT_MEMTEST: 1943 Enable an alternate, more extensive memory test. 1944 1945- CFG_MEMTEST_SCRATCH: 1946 Scratch address used by the alternate memory test 1947 You only need to set this if address zero isn't writeable 1948 1949- CFG_MEM_TOP_HIDE (PPC only): 1950 If CFG_MEM_TOP_HIDE is defined in the board config header, 1951 this specified memory area will get subtracted from the top 1952 (end) of ram and won't get "touched" at all by U-Boot. By 1953 fixing up gd->ram_size the Linux kernel should gets passed 1954 the now "corrected" memory size and won't touch it either. 1955 This should work for arch/ppc and arch/powerpc. Only Linux 1956 board ports in arch/powerpc with bootwrapper support that 1957 recalculate the memory size from the SDRAM controller setup 1958 will have to get fixed in Linux additionally. 1959 1960 This option can be used as a workaround for the 440EPx/GRx 1961 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 1962 be touched. 1963 1964 WARNING: Please make sure that this value is a multiple of 1965 the Linux page size (normally 4k). If this is not the case, 1966 then the end address of the Linux memory will be located at a 1967 non page size aligned address and this could cause major 1968 problems. 1969 1970- CFG_TFTP_LOADADDR: 1971 Default load address for network file downloads 1972 1973- CFG_LOADS_BAUD_CHANGE: 1974 Enable temporary baudrate change while serial download 1975 1976- CFG_SDRAM_BASE: 1977 Physical start address of SDRAM. _Must_ be 0 here. 1978 1979- CFG_MBIO_BASE: 1980 Physical start address of Motherboard I/O (if using a 1981 Cogent motherboard) 1982 1983- CFG_FLASH_BASE: 1984 Physical start address of Flash memory. 1985 1986- CFG_MONITOR_BASE: 1987 Physical start address of boot monitor code (set by 1988 make config files to be same as the text base address 1989 (TEXT_BASE) used when linking) - same as 1990 CFG_FLASH_BASE when booting from flash. 1991 1992- CFG_MONITOR_LEN: 1993 Size of memory reserved for monitor code, used to 1994 determine _at_compile_time_ (!) if the environment is 1995 embedded within the U-Boot image, or in a separate 1996 flash sector. 1997 1998- CFG_MALLOC_LEN: 1999 Size of DRAM reserved for malloc() use. 2000 2001- CFG_BOOTM_LEN: 2002 Normally compressed uImages are limited to an 2003 uncompressed size of 8 MBytes. If this is not enough, 2004 you can define CFG_BOOTM_LEN in your board config file 2005 to adjust this setting to your needs. 2006 2007- CFG_BOOTMAPSZ: 2008 Maximum size of memory mapped by the startup code of 2009 the Linux kernel; all data that must be processed by 2010 the Linux kernel (bd_info, boot arguments, eventually 2011 initrd image) must be put below this limit. 2012 2013- CFG_MAX_FLASH_BANKS: 2014 Max number of Flash memory banks 2015 2016- CFG_MAX_FLASH_SECT: 2017 Max number of sectors on a Flash chip 2018 2019- CFG_FLASH_ERASE_TOUT: 2020 Timeout for Flash erase operations (in ms) 2021 2022- CFG_FLASH_WRITE_TOUT: 2023 Timeout for Flash write operations (in ms) 2024 2025- CFG_FLASH_LOCK_TOUT 2026 Timeout for Flash set sector lock bit operation (in ms) 2027 2028- CFG_FLASH_UNLOCK_TOUT 2029 Timeout for Flash clear lock bits operation (in ms) 2030 2031- CFG_FLASH_PROTECTION 2032 If defined, hardware flash sectors protection is used 2033 instead of U-Boot software protection. 2034 2035- CFG_DIRECT_FLASH_TFTP: 2036 2037 Enable TFTP transfers directly to flash memory; 2038 without this option such a download has to be 2039 performed in two steps: (1) download to RAM, and (2) 2040 copy from RAM to flash. 2041 2042 The two-step approach is usually more reliable, since 2043 you can check if the download worked before you erase 2044 the flash, but in some situations (when sytem RAM is 2045 too limited to allow for a tempory copy of the 2046 downloaded image) this option may be very useful. 2047 2048- CFG_FLASH_CFI: 2049 Define if the flash driver uses extra elements in the 2050 common flash structure for storing flash geometry. 2051 2052- CFG_FLASH_CFI_DRIVER 2053 This option also enables the building of the cfi_flash driver 2054 in the drivers directory 2055 2056- CFG_FLASH_QUIET_TEST 2057 If this option is defined, the common CFI flash doesn't 2058 print it's warning upon not recognized FLASH banks. This 2059 is useful, if some of the configured banks are only 2060 optionally available. 2061 2062- CONFIG_FLASH_SHOW_PROGRESS 2063 If defined (must be an integer), print out countdown 2064 digits and dots. Recommended value: 45 (9..1) for 80 2065 column displays, 15 (3..1) for 40 column displays. 2066 2067- CFG_RX_ETH_BUFFER: 2068 Defines the number of ethernet receive buffers. On some 2069 ethernet controllers it is recommended to set this value 2070 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2071 buffers can be full shortly after enabling the interface 2072 on high ethernet traffic. 2073 Defaults to 4 if not defined. 2074 2075The following definitions that deal with the placement and management 2076of environment data (variable area); in general, we support the 2077following configurations: 2078 2079- CFG_ENV_IS_IN_FLASH: 2080 2081 Define this if the environment is in flash memory. 2082 2083 a) The environment occupies one whole flash sector, which is 2084 "embedded" in the text segment with the U-Boot code. This 2085 happens usually with "bottom boot sector" or "top boot 2086 sector" type flash chips, which have several smaller 2087 sectors at the start or the end. For instance, such a 2088 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2089 such a case you would place the environment in one of the 2090 4 kB sectors - with U-Boot code before and after it. With 2091 "top boot sector" type flash chips, you would put the 2092 environment in one of the last sectors, leaving a gap 2093 between U-Boot and the environment. 2094 2095 - CFG_ENV_OFFSET: 2096 2097 Offset of environment data (variable area) to the 2098 beginning of flash memory; for instance, with bottom boot 2099 type flash chips the second sector can be used: the offset 2100 for this sector is given here. 2101 2102 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2103 2104 - CFG_ENV_ADDR: 2105 2106 This is just another way to specify the start address of 2107 the flash sector containing the environment (instead of 2108 CFG_ENV_OFFSET). 2109 2110 - CFG_ENV_SECT_SIZE: 2111 2112 Size of the sector containing the environment. 2113 2114 2115 b) Sometimes flash chips have few, equal sized, BIG sectors. 2116 In such a case you don't want to spend a whole sector for 2117 the environment. 2118 2119 - CFG_ENV_SIZE: 2120 2121 If you use this in combination with CFG_ENV_IS_IN_FLASH 2122 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2123 of this flash sector for the environment. This saves 2124 memory for the RAM copy of the environment. 2125 2126 It may also save flash memory if you decide to use this 2127 when your environment is "embedded" within U-Boot code, 2128 since then the remainder of the flash sector could be used 2129 for U-Boot code. It should be pointed out that this is 2130 STRONGLY DISCOURAGED from a robustness point of view: 2131 updating the environment in flash makes it always 2132 necessary to erase the WHOLE sector. If something goes 2133 wrong before the contents has been restored from a copy in 2134 RAM, your target system will be dead. 2135 2136 - CFG_ENV_ADDR_REDUND 2137 CFG_ENV_SIZE_REDUND 2138 2139 These settings describe a second storage area used to hold 2140 a redundand copy of the environment data, so that there is 2141 a valid backup copy in case there is a power failure during 2142 a "saveenv" operation. 2143 2144BE CAREFUL! Any changes to the flash layout, and some changes to the 2145source code will make it necessary to adapt <board>/u-boot.lds* 2146accordingly! 2147 2148 2149- CFG_ENV_IS_IN_NVRAM: 2150 2151 Define this if you have some non-volatile memory device 2152 (NVRAM, battery buffered SRAM) which you want to use for the 2153 environment. 2154 2155 - CFG_ENV_ADDR: 2156 - CFG_ENV_SIZE: 2157 2158 These two #defines are used to determin the memory area you 2159 want to use for environment. It is assumed that this memory 2160 can just be read and written to, without any special 2161 provision. 2162 2163BE CAREFUL! The first access to the environment happens quite early 2164in U-Boot initalization (when we try to get the setting of for the 2165console baudrate). You *MUST* have mappend your NVRAM area then, or 2166U-Boot will hang. 2167 2168Please note that even with NVRAM we still use a copy of the 2169environment in RAM: we could work on NVRAM directly, but we want to 2170keep settings there always unmodified except somebody uses "saveenv" 2171to save the current settings. 2172 2173 2174- CFG_ENV_IS_IN_EEPROM: 2175 2176 Use this if you have an EEPROM or similar serial access 2177 device and a driver for it. 2178 2179 - CFG_ENV_OFFSET: 2180 - CFG_ENV_SIZE: 2181 2182 These two #defines specify the offset and size of the 2183 environment area within the total memory of your EEPROM. 2184 2185 - CFG_I2C_EEPROM_ADDR: 2186 If defined, specified the chip address of the EEPROM device. 2187 The default address is zero. 2188 2189 - CFG_EEPROM_PAGE_WRITE_BITS: 2190 If defined, the number of bits used to address bytes in a 2191 single page in the EEPROM device. A 64 byte page, for example 2192 would require six bits. 2193 2194 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2195 If defined, the number of milliseconds to delay between 2196 page writes. The default is zero milliseconds. 2197 2198 - CFG_I2C_EEPROM_ADDR_LEN: 2199 The length in bytes of the EEPROM memory array address. Note 2200 that this is NOT the chip address length! 2201 2202 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2203 EEPROM chips that implement "address overflow" are ones 2204 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2205 address and the extra bits end up in the "chip address" bit 2206 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2207 byte chips. 2208 2209 Note that we consider the length of the address field to 2210 still be one byte because the extra address bits are hidden 2211 in the chip address. 2212 2213 - CFG_EEPROM_SIZE: 2214 The size in bytes of the EEPROM device. 2215 2216 2217- CFG_ENV_IS_IN_DATAFLASH: 2218 2219 Define this if you have a DataFlash memory device which you 2220 want to use for the environment. 2221 2222 - CFG_ENV_OFFSET: 2223 - CFG_ENV_ADDR: 2224 - CFG_ENV_SIZE: 2225 2226 These three #defines specify the offset and size of the 2227 environment area within the total memory of your DataFlash placed 2228 at the specified address. 2229 2230- CFG_ENV_IS_IN_NAND: 2231 2232 Define this if you have a NAND device which you want to use 2233 for the environment. 2234 2235 - CFG_ENV_OFFSET: 2236 - CFG_ENV_SIZE: 2237 2238 These two #defines specify the offset and size of the environment 2239 area within the first NAND device. 2240 2241 - CFG_ENV_OFFSET_REDUND 2242 2243 This setting describes a second storage area of CFG_ENV_SIZE 2244 size used to hold a redundant copy of the environment data, 2245 so that there is a valid backup copy in case there is a 2246 power failure during a "saveenv" operation. 2247 2248 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2249 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2250 the NAND devices block size. 2251 2252- CFG_SPI_INIT_OFFSET 2253 2254 Defines offset to the initial SPI buffer area in DPRAM. The 2255 area is used at an early stage (ROM part) if the environment 2256 is configured to reside in the SPI EEPROM: We need a 520 byte 2257 scratch DPRAM area. It is used between the two initialization 2258 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2259 to be a good choice since it makes it far enough from the 2260 start of the data area as well as from the stack pointer. 2261 2262Please note that the environment is read-only until the monitor 2263has been relocated to RAM and a RAM copy of the environment has been 2264created; also, when using EEPROM you will have to use getenv_r() 2265until then to read environment variables. 2266 2267The environment is protected by a CRC32 checksum. Before the monitor 2268is relocated into RAM, as a result of a bad CRC you will be working 2269with the compiled-in default environment - *silently*!!! [This is 2270necessary, because the first environment variable we need is the 2271"baudrate" setting for the console - if we have a bad CRC, we don't 2272have any device yet where we could complain.] 2273 2274Note: once the monitor has been relocated, then it will complain if 2275the default environment is used; a new CRC is computed as soon as you 2276use the "saveenv" command to store a valid environment. 2277 2278- CFG_FAULT_ECHO_LINK_DOWN: 2279 Echo the inverted Ethernet link state to the fault LED. 2280 2281 Note: If this option is active, then CFG_FAULT_MII_ADDR 2282 also needs to be defined. 2283 2284- CFG_FAULT_MII_ADDR: 2285 MII address of the PHY to check for the Ethernet link state. 2286 2287- CFG_64BIT_VSPRINTF: 2288 Makes vsprintf (and all *printf functions) support printing 2289 of 64bit values by using the L quantifier 2290 2291- CFG_64BIT_STRTOUL: 2292 Adds simple_strtoull that returns a 64bit value 2293 2294Low Level (hardware related) configuration options: 2295--------------------------------------------------- 2296 2297- CFG_CACHELINE_SIZE: 2298 Cache Line Size of the CPU. 2299 2300- CFG_DEFAULT_IMMR: 2301 Default address of the IMMR after system reset. 2302 2303 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2304 and RPXsuper) to be able to adjust the position of 2305 the IMMR register after a reset. 2306 2307- Floppy Disk Support: 2308 CFG_FDC_DRIVE_NUMBER 2309 2310 the default drive number (default value 0) 2311 2312 CFG_ISA_IO_STRIDE 2313 2314 defines the spacing between fdc chipset registers 2315 (default value 1) 2316 2317 CFG_ISA_IO_OFFSET 2318 2319 defines the offset of register from address. It 2320 depends on which part of the data bus is connected to 2321 the fdc chipset. (default value 0) 2322 2323 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2324 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2325 default value. 2326 2327 if CFG_FDC_HW_INIT is defined, then the function 2328 fdc_hw_init() is called at the beginning of the FDC 2329 setup. fdc_hw_init() must be provided by the board 2330 source code. It is used to make hardware dependant 2331 initializations. 2332 2333- CFG_IMMR: Physical address of the Internal Memory. 2334 DO NOT CHANGE unless you know exactly what you're 2335 doing! (11-4) [MPC8xx/82xx systems only] 2336 2337- CFG_INIT_RAM_ADDR: 2338 2339 Start address of memory area that can be used for 2340 initial data and stack; please note that this must be 2341 writable memory that is working WITHOUT special 2342 initialization, i. e. you CANNOT use normal RAM which 2343 will become available only after programming the 2344 memory controller and running certain initialization 2345 sequences. 2346 2347 U-Boot uses the following memory types: 2348 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2349 - MPC824X: data cache 2350 - PPC4xx: data cache 2351 2352- CFG_GBL_DATA_OFFSET: 2353 2354 Offset of the initial data structure in the memory 2355 area defined by CFG_INIT_RAM_ADDR. Usually 2356 CFG_GBL_DATA_OFFSET is chosen such that the initial 2357 data is located at the end of the available space 2358 (sometimes written as (CFG_INIT_RAM_END - 2359 CFG_INIT_DATA_SIZE), and the initial stack is just 2360 below that area (growing from (CFG_INIT_RAM_ADDR + 2361 CFG_GBL_DATA_OFFSET) downward. 2362 2363 Note: 2364 On the MPC824X (or other systems that use the data 2365 cache for initial memory) the address chosen for 2366 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2367 point to an otherwise UNUSED address space between 2368 the top of RAM and the start of the PCI space. 2369 2370- CFG_SIUMCR: SIU Module Configuration (11-6) 2371 2372- CFG_SYPCR: System Protection Control (11-9) 2373 2374- CFG_TBSCR: Time Base Status and Control (11-26) 2375 2376- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2377 2378- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2379 2380- CFG_SCCR: System Clock and reset Control Register (15-27) 2381 2382- CFG_OR_TIMING_SDRAM: 2383 SDRAM timing 2384 2385- CFG_MAMR_PTA: 2386 periodic timer for refresh 2387 2388- CFG_DER: Debug Event Register (37-47) 2389 2390- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2391 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2392 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2393 CFG_BR1_PRELIM: 2394 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2395 2396- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2397 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2398 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2399 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2400 2401- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2402 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2403 Machine Mode Register and Memory Periodic Timer 2404 Prescaler definitions (SDRAM timing) 2405 2406- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2407 enable I2C microcode relocation patch (MPC8xx); 2408 define relocation offset in DPRAM [DSP2] 2409 2410- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2411 enable SMC microcode relocation patch (MPC8xx); 2412 define relocation offset in DPRAM [SMC1] 2413 2414- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2415 enable SPI microcode relocation patch (MPC8xx); 2416 define relocation offset in DPRAM [SCC4] 2417 2418- CFG_USE_OSCCLK: 2419 Use OSCM clock mode on MBX8xx board. Be careful, 2420 wrong setting might damage your board. Read 2421 doc/README.MBX before setting this variable! 2422 2423- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2424 Offset of the bootmode word in DPRAM used by post 2425 (Power On Self Tests). This definition overrides 2426 #define'd default value in commproc.h resp. 2427 cpm_8260.h. 2428 2429- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2430 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2431 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2432 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2433 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2434 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2435 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2436 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2437 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2438 2439- CONFIG_SPD_EEPROM 2440 Get DDR timing information from an I2C EEPROM. Common 2441 with pluggable memory modules such as SODIMMs 2442 2443 SPD_EEPROM_ADDRESS 2444 I2C address of the SPD EEPROM 2445 2446- CFG_SPD_BUS_NUM 2447 If SPD EEPROM is on an I2C bus other than the first 2448 one, specify here. Note that the value must resolve 2449 to something your driver can deal with. 2450 2451- CFG_83XX_DDR_USES_CS0 2452 Only for 83xx systems. If specified, then DDR should 2453 be configured using CS0 and CS1 instead of CS2 and CS3. 2454 2455- CFG_83XX_DDR_USES_CS0 2456 Only for 83xx systems. If specified, then DDR should 2457 be configured using CS0 and CS1 instead of CS2 and CS3. 2458 2459- CONFIG_ETHER_ON_FEC[12] 2460 Define to enable FEC[12] on a 8xx series processor. 2461 2462- CONFIG_FEC[12]_PHY 2463 Define to the hardcoded PHY address which corresponds 2464 to the given FEC; i. e. 2465 #define CONFIG_FEC1_PHY 4 2466 means that the PHY with address 4 is connected to FEC1 2467 2468 When set to -1, means to probe for first available. 2469 2470- CONFIG_FEC[12]_PHY_NORXERR 2471 The PHY does not have a RXERR line (RMII only). 2472 (so program the FEC to ignore it). 2473 2474- CONFIG_RMII 2475 Enable RMII mode for all FECs. 2476 Note that this is a global option, we can't 2477 have one FEC in standard MII mode and another in RMII mode. 2478 2479- CONFIG_CRC32_VERIFY 2480 Add a verify option to the crc32 command. 2481 The syntax is: 2482 2483 => crc32 -v <address> <count> <crc32> 2484 2485 Where address/count indicate a memory area 2486 and crc32 is the correct crc32 which the 2487 area should have. 2488 2489- CONFIG_LOOPW 2490 Add the "loopw" memory command. This only takes effect if 2491 the memory commands are activated globally (CONFIG_CMD_MEM). 2492 2493- CONFIG_MX_CYCLIC 2494 Add the "mdc" and "mwc" memory commands. These are cyclic 2495 "md/mw" commands. 2496 Examples: 2497 2498 => mdc.b 10 4 500 2499 This command will print 4 bytes (10,11,12,13) each 500 ms. 2500 2501 => mwc.l 100 12345678 10 2502 This command will write 12345678 to address 100 all 10 ms. 2503 2504 This only takes effect if the memory commands are activated 2505 globally (CONFIG_CMD_MEM). 2506 2507- CONFIG_SKIP_LOWLEVEL_INIT 2508- CONFIG_SKIP_RELOCATE_UBOOT 2509 2510 [ARM only] If these variables are defined, then 2511 certain low level initializations (like setting up 2512 the memory controller) are omitted and/or U-Boot does 2513 not relocate itself into RAM. 2514 Normally these variables MUST NOT be defined. The 2515 only exception is when U-Boot is loaded (to RAM) by 2516 some other boot loader or by a debugger which 2517 performs these intializations itself. 2518 2519 2520Building the Software: 2521====================== 2522 2523Building U-Boot has been tested in several native build environments 2524and in many different cross environments. Of course we cannot support 2525all possibly existing versions of cross development tools in all 2526(potentially obsolete) versions. In case of tool chain problems we 2527recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2528which is extensively used to build and test U-Boot. 2529 2530If you are not using a native environment, it is assumed that you 2531have GNU cross compiling tools available in your path. In this case, 2532you must set the environment variable CROSS_COMPILE in your shell. 2533Note that no changes to the Makefile or any other source files are 2534necessary. For example using the ELDK on a 4xx CPU, please enter: 2535 2536 $ CROSS_COMPILE=ppc_4xx- 2537 $ export CROSS_COMPILE 2538 2539U-Boot is intended to be simple to build. After installing the 2540sources you must configure U-Boot for one specific board type. This 2541is done by typing: 2542 2543 make NAME_config 2544 2545where "NAME_config" is the name of one of the existing configu- 2546rations; see the main Makefile for supported names. 2547 2548Note: for some board special configuration names may exist; check if 2549 additional information is available from the board vendor; for 2550 instance, the TQM823L systems are available without (standard) 2551 or with LCD support. You can select such additional "features" 2552 when chosing the configuration, i. e. 2553 2554 make TQM823L_config 2555 - will configure for a plain TQM823L, i. e. no LCD support 2556 2557 make TQM823L_LCD_config 2558 - will configure for a TQM823L with U-Boot console on LCD 2559 2560 etc. 2561 2562 2563Finally, type "make all", and you should get some working U-Boot 2564images ready for download to / installation on your system: 2565 2566- "u-boot.bin" is a raw binary image 2567- "u-boot" is an image in ELF binary format 2568- "u-boot.srec" is in Motorola S-Record format 2569 2570By default the build is performed locally and the objects are saved 2571in the source directory. One of the two methods can be used to change 2572this behavior and build U-Boot to some external directory: 2573 25741. Add O= to the make command line invocations: 2575 2576 make O=/tmp/build distclean 2577 make O=/tmp/build NAME_config 2578 make O=/tmp/build all 2579 25802. Set environment variable BUILD_DIR to point to the desired location: 2581 2582 export BUILD_DIR=/tmp/build 2583 make distclean 2584 make NAME_config 2585 make all 2586 2587Note that the command line "O=" setting overrides the BUILD_DIR environment 2588variable. 2589 2590 2591Please be aware that the Makefiles assume you are using GNU make, so 2592for instance on NetBSD you might need to use "gmake" instead of 2593native "make". 2594 2595 2596If the system board that you have is not listed, then you will need 2597to port U-Boot to your hardware platform. To do this, follow these 2598steps: 2599 26001. Add a new configuration option for your board to the toplevel 2601 "Makefile" and to the "MAKEALL" script, using the existing 2602 entries as examples. Note that here and at many other places 2603 boards and other names are listed in alphabetical sort order. Please 2604 keep this order. 26052. Create a new directory to hold your board specific code. Add any 2606 files you need. In your board directory, you will need at least 2607 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 26083. Create a new configuration file "include/configs/<board>.h" for 2609 your board 26103. If you're porting U-Boot to a new CPU, then also create a new 2611 directory to hold your CPU specific code. Add any files you need. 26124. Run "make <board>_config" with your new name. 26135. Type "make", and you should get a working "u-boot.srec" file 2614 to be installed on your target system. 26156. Debug and solve any problems that might arise. 2616 [Of course, this last step is much harder than it sounds.] 2617 2618 2619Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2620============================================================== 2621 2622If you have modified U-Boot sources (for instance added a new board 2623or support for new devices, a new CPU, etc.) you are expected to 2624provide feedback to the other developers. The feedback normally takes 2625the form of a "patch", i. e. a context diff against a certain (latest 2626official or latest in the git repository) version of U-Boot sources. 2627 2628But before you submit such a patch, please verify that your modifi- 2629cation did not break existing code. At least make sure that *ALL* of 2630the supported boards compile WITHOUT ANY compiler warnings. To do so, 2631just run the "MAKEALL" script, which will configure and build U-Boot 2632for ALL supported system. Be warned, this will take a while. You can 2633select which (cross) compiler to use by passing a `CROSS_COMPILE' 2634environment variable to the script, i. e. to use the ELDK cross tools 2635you can type 2636 2637 CROSS_COMPILE=ppc_8xx- MAKEALL 2638 2639or to build on a native PowerPC system you can type 2640 2641 CROSS_COMPILE=' ' MAKEALL 2642 2643When using the MAKEALL script, the default behaviour is to build 2644U-Boot in the source directory. This location can be changed by 2645setting the BUILD_DIR environment variable. Also, for each target 2646built, the MAKEALL script saves two log files (<target>.ERR and 2647<target>.MAKEALL) in the <source dir>/LOG directory. This default 2648location can be changed by setting the MAKEALL_LOGDIR environment 2649variable. For example: 2650 2651 export BUILD_DIR=/tmp/build 2652 export MAKEALL_LOGDIR=/tmp/log 2653 CROSS_COMPILE=ppc_8xx- MAKEALL 2654 2655With the above settings build objects are saved in the /tmp/build, 2656log files are saved in the /tmp/log and the source tree remains clean 2657during the whole build process. 2658 2659 2660See also "U-Boot Porting Guide" below. 2661 2662 2663Monitor Commands - Overview: 2664============================ 2665 2666go - start application at address 'addr' 2667run - run commands in an environment variable 2668bootm - boot application image from memory 2669bootp - boot image via network using BootP/TFTP protocol 2670tftpboot- boot image via network using TFTP protocol 2671 and env variables "ipaddr" and "serverip" 2672 (and eventually "gatewayip") 2673rarpboot- boot image via network using RARP/TFTP protocol 2674diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2675loads - load S-Record file over serial line 2676loadb - load binary file over serial line (kermit mode) 2677md - memory display 2678mm - memory modify (auto-incrementing) 2679nm - memory modify (constant address) 2680mw - memory write (fill) 2681cp - memory copy 2682cmp - memory compare 2683crc32 - checksum calculation 2684imd - i2c memory display 2685imm - i2c memory modify (auto-incrementing) 2686inm - i2c memory modify (constant address) 2687imw - i2c memory write (fill) 2688icrc32 - i2c checksum calculation 2689iprobe - probe to discover valid I2C chip addresses 2690iloop - infinite loop on address range 2691isdram - print SDRAM configuration information 2692sspi - SPI utility commands 2693base - print or set address offset 2694printenv- print environment variables 2695setenv - set environment variables 2696saveenv - save environment variables to persistent storage 2697protect - enable or disable FLASH write protection 2698erase - erase FLASH memory 2699flinfo - print FLASH memory information 2700bdinfo - print Board Info structure 2701iminfo - print header information for application image 2702coninfo - print console devices and informations 2703ide - IDE sub-system 2704loop - infinite loop on address range 2705loopw - infinite write loop on address range 2706mtest - simple RAM test 2707icache - enable or disable instruction cache 2708dcache - enable or disable data cache 2709reset - Perform RESET of the CPU 2710echo - echo args to console 2711version - print monitor version 2712help - print online help 2713? - alias for 'help' 2714 2715 2716Monitor Commands - Detailed Description: 2717======================================== 2718 2719TODO. 2720 2721For now: just type "help <command>". 2722 2723 2724Environment Variables: 2725====================== 2726 2727U-Boot supports user configuration using Environment Variables which 2728can be made persistent by saving to Flash memory. 2729 2730Environment Variables are set using "setenv", printed using 2731"printenv", and saved to Flash using "saveenv". Using "setenv" 2732without a value can be used to delete a variable from the 2733environment. As long as you don't save the environment you are 2734working with an in-memory copy. In case the Flash area containing the 2735environment is erased by accident, a default environment is provided. 2736 2737Some configuration options can be set using Environment Variables: 2738 2739 baudrate - see CONFIG_BAUDRATE 2740 2741 bootdelay - see CONFIG_BOOTDELAY 2742 2743 bootcmd - see CONFIG_BOOTCOMMAND 2744 2745 bootargs - Boot arguments when booting an RTOS image 2746 2747 bootfile - Name of the image to load with TFTP 2748 2749 autoload - if set to "no" (any string beginning with 'n'), 2750 "bootp" will just load perform a lookup of the 2751 configuration from the BOOTP server, but not try to 2752 load any image using TFTP 2753 2754 autoscript - if set to "yes" commands like "loadb", "loady", 2755 "bootp", "tftpb", "rarpboot" and "nfs" will attempt 2756 to automatically run script images (by internally 2757 calling "autoscript"). 2758 2759 autoscript_uname - if script image is in a format (FIT) this 2760 variable is used to get script subimage unit name. 2761 2762 autostart - if set to "yes", an image loaded using the "bootp", 2763 "rarpboot", "tftpboot" or "diskboot" commands will 2764 be automatically started (by internally calling 2765 "bootm") 2766 2767 If set to "no", a standalone image passed to the 2768 "bootm" command will be copied to the load address 2769 (and eventually uncompressed), but NOT be started. 2770 This can be used to load and uncompress arbitrary 2771 data. 2772 2773 i2cfast - (PPC405GP|PPC405EP only) 2774 if set to 'y' configures Linux I2C driver for fast 2775 mode (400kHZ). This environment variable is used in 2776 initialization code. So, for changes to be effective 2777 it must be saved and board must be reset. 2778 2779 initrd_high - restrict positioning of initrd images: 2780 If this variable is not set, initrd images will be 2781 copied to the highest possible address in RAM; this 2782 is usually what you want since it allows for 2783 maximum initrd size. If for some reason you want to 2784 make sure that the initrd image is loaded below the 2785 CFG_BOOTMAPSZ limit, you can set this environment 2786 variable to a value of "no" or "off" or "0". 2787 Alternatively, you can set it to a maximum upper 2788 address to use (U-Boot will still check that it 2789 does not overwrite the U-Boot stack and data). 2790 2791 For instance, when you have a system with 16 MB 2792 RAM, and want to reserve 4 MB from use by Linux, 2793 you can do this by adding "mem=12M" to the value of 2794 the "bootargs" variable. However, now you must make 2795 sure that the initrd image is placed in the first 2796 12 MB as well - this can be done with 2797 2798 setenv initrd_high 00c00000 2799 2800 If you set initrd_high to 0xFFFFFFFF, this is an 2801 indication to U-Boot that all addresses are legal 2802 for the Linux kernel, including addresses in flash 2803 memory. In this case U-Boot will NOT COPY the 2804 ramdisk at all. This may be useful to reduce the 2805 boot time on your system, but requires that this 2806 feature is supported by your Linux kernel. 2807 2808 ipaddr - IP address; needed for tftpboot command 2809 2810 loadaddr - Default load address for commands like "bootp", 2811 "rarpboot", "tftpboot", "loadb" or "diskboot" 2812 2813 loads_echo - see CONFIG_LOADS_ECHO 2814 2815 serverip - TFTP server IP address; needed for tftpboot command 2816 2817 bootretry - see CONFIG_BOOT_RETRY_TIME 2818 2819 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2820 2821 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2822 2823 ethprime - When CONFIG_NET_MULTI is enabled controls which 2824 interface is used first. 2825 2826 ethact - When CONFIG_NET_MULTI is enabled controls which 2827 interface is currently active. For example you 2828 can do the following 2829 2830 => setenv ethact FEC ETHERNET 2831 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2832 => setenv ethact SCC ETHERNET 2833 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2834 2835 ethrotate - When set to "no" U-Boot does not go through all 2836 available network interfaces. 2837 It just stays at the currently selected interface. 2838 2839 netretry - When set to "no" each network operation will 2840 either succeed or fail without retrying. 2841 When set to "once" the network operation will 2842 fail when all the available network interfaces 2843 are tried once without success. 2844 Useful on scripts which control the retry operation 2845 themselves. 2846 2847 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2848 if set load address for the npe microcode 2849 2850 tftpsrcport - If this is set, the value is used for TFTP's 2851 UDP source port. 2852 2853 tftpdstport - If this is set, the value is used for TFTP's UDP 2854 destination port instead of the Well Know Port 69. 2855 2856 vlan - When set to a value < 4095 the traffic over 2857 ethernet is encapsulated/received over 802.1q 2858 VLAN tagged frames. 2859 2860The following environment variables may be used and automatically 2861updated by the network boot commands ("bootp" and "rarpboot"), 2862depending the information provided by your boot server: 2863 2864 bootfile - see above 2865 dnsip - IP address of your Domain Name Server 2866 dnsip2 - IP address of your secondary Domain Name Server 2867 gatewayip - IP address of the Gateway (Router) to use 2868 hostname - Target hostname 2869 ipaddr - see above 2870 netmask - Subnet Mask 2871 rootpath - Pathname of the root filesystem on the NFS server 2872 serverip - see above 2873 2874 2875There are two special Environment Variables: 2876 2877 serial# - contains hardware identification information such 2878 as type string and/or serial number 2879 ethaddr - Ethernet address 2880 2881These variables can be set only once (usually during manufacturing of 2882the board). U-Boot refuses to delete or overwrite these variables 2883once they have been set once. 2884 2885 2886Further special Environment Variables: 2887 2888 ver - Contains the U-Boot version string as printed 2889 with the "version" command. This variable is 2890 readonly (see CONFIG_VERSION_VARIABLE). 2891 2892 2893Please note that changes to some configuration parameters may take 2894only effect after the next boot (yes, that's just like Windoze :-). 2895 2896 2897Command Line Parsing: 2898===================== 2899 2900There are two different command line parsers available with U-Boot: 2901the old "simple" one, and the much more powerful "hush" shell: 2902 2903Old, simple command line parser: 2904-------------------------------- 2905 2906- supports environment variables (through setenv / saveenv commands) 2907- several commands on one line, separated by ';' 2908- variable substitution using "... ${name} ..." syntax 2909- special characters ('$', ';') can be escaped by prefixing with '\', 2910 for example: 2911 setenv bootcmd bootm \${address} 2912- You can also escape text by enclosing in single apostrophes, for example: 2913 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2914 2915Hush shell: 2916----------- 2917 2918- similar to Bourne shell, with control structures like 2919 if...then...else...fi, for...do...done; while...do...done, 2920 until...do...done, ... 2921- supports environment ("global") variables (through setenv / saveenv 2922 commands) and local shell variables (through standard shell syntax 2923 "name=value"); only environment variables can be used with "run" 2924 command 2925 2926General rules: 2927-------------- 2928 2929(1) If a command line (or an environment variable executed by a "run" 2930 command) contains several commands separated by semicolon, and 2931 one of these commands fails, then the remaining commands will be 2932 executed anyway. 2933 2934(2) If you execute several variables with one call to run (i. e. 2935 calling run with a list af variables as arguments), any failing 2936 command will cause "run" to terminate, i. e. the remaining 2937 variables are not executed. 2938 2939Note for Redundant Ethernet Interfaces: 2940======================================= 2941 2942Some boards come with redundant ethernet interfaces; U-Boot supports 2943such configurations and is capable of automatic selection of a 2944"working" interface when needed. MAC assignment works as follows: 2945 2946Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2947MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2948"eth1addr" (=>eth1), "eth2addr", ... 2949 2950If the network interface stores some valid MAC address (for instance 2951in SROM), this is used as default address if there is NO correspon- 2952ding setting in the environment; if the corresponding environment 2953variable is set, this overrides the settings in the card; that means: 2954 2955o If the SROM has a valid MAC address, and there is no address in the 2956 environment, the SROM's address is used. 2957 2958o If there is no valid address in the SROM, and a definition in the 2959 environment exists, then the value from the environment variable is 2960 used. 2961 2962o If both the SROM and the environment contain a MAC address, and 2963 both addresses are the same, this MAC address is used. 2964 2965o If both the SROM and the environment contain a MAC address, and the 2966 addresses differ, the value from the environment is used and a 2967 warning is printed. 2968 2969o If neither SROM nor the environment contain a MAC address, an error 2970 is raised. 2971 2972 2973Image Formats: 2974============== 2975 2976U-Boot is capable of booting (and performing other auxiliary operations on) 2977images in two formats: 2978 2979New uImage format (FIT) 2980----------------------- 2981 2982Flexible and powerful format based on Flattened Image Tree -- FIT (similar 2983to Flattened Device Tree). It allows the use of images with multiple 2984components (several kernels, ramdisks, etc.), with contents protected by 2985SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 2986 2987 2988Old uImage format 2989----------------- 2990 2991Old image format is based on binary files which can be basically anything, 2992preceded by a special header; see the definitions in include/image.h for 2993details; basically, the header defines the following image properties: 2994 2995* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2996 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2997 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2998 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2999* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3000 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3001 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 3002* Compression Type (uncompressed, gzip, bzip2) 3003* Load Address 3004* Entry Point 3005* Image Name 3006* Image Timestamp 3007 3008The header is marked by a special Magic Number, and both the header 3009and the data portions of the image are secured against corruption by 3010CRC32 checksums. 3011 3012 3013Linux Support: 3014============== 3015 3016Although U-Boot should support any OS or standalone application 3017easily, the main focus has always been on Linux during the design of 3018U-Boot. 3019 3020U-Boot includes many features that so far have been part of some 3021special "boot loader" code within the Linux kernel. Also, any 3022"initrd" images to be used are no longer part of one big Linux image; 3023instead, kernel and "initrd" are separate images. This implementation 3024serves several purposes: 3025 3026- the same features can be used for other OS or standalone 3027 applications (for instance: using compressed images to reduce the 3028 Flash memory footprint) 3029 3030- it becomes much easier to port new Linux kernel versions because 3031 lots of low-level, hardware dependent stuff are done by U-Boot 3032 3033- the same Linux kernel image can now be used with different "initrd" 3034 images; of course this also means that different kernel images can 3035 be run with the same "initrd". This makes testing easier (you don't 3036 have to build a new "zImage.initrd" Linux image when you just 3037 change a file in your "initrd"). Also, a field-upgrade of the 3038 software is easier now. 3039 3040 3041Linux HOWTO: 3042============ 3043 3044Porting Linux to U-Boot based systems: 3045--------------------------------------- 3046 3047U-Boot cannot save you from doing all the necessary modifications to 3048configure the Linux device drivers for use with your target hardware 3049(no, we don't intend to provide a full virtual machine interface to 3050Linux :-). 3051 3052But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 3053 3054Just make sure your machine specific header file (for instance 3055include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3056Information structure as we define in include/u-boot.h, and make 3057sure that your definition of IMAP_ADDR uses the same value as your 3058U-Boot configuration in CFG_IMMR. 3059 3060 3061Configuring the Linux kernel: 3062----------------------------- 3063 3064No specific requirements for U-Boot. Make sure you have some root 3065device (initial ramdisk, NFS) for your target system. 3066 3067 3068Building a Linux Image: 3069----------------------- 3070 3071With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3072not used. If you use recent kernel source, a new build target 3073"uImage" will exist which automatically builds an image usable by 3074U-Boot. Most older kernels also have support for a "pImage" target, 3075which was introduced for our predecessor project PPCBoot and uses a 3076100% compatible format. 3077 3078Example: 3079 3080 make TQM850L_config 3081 make oldconfig 3082 make dep 3083 make uImage 3084 3085The "uImage" build target uses a special tool (in 'tools/mkimage') to 3086encapsulate a compressed Linux kernel image with header information, 3087CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3088 3089* build a standard "vmlinux" kernel image (in ELF binary format): 3090 3091* convert the kernel into a raw binary image: 3092 3093 ${CROSS_COMPILE}-objcopy -O binary \ 3094 -R .note -R .comment \ 3095 -S vmlinux linux.bin 3096 3097* compress the binary image: 3098 3099 gzip -9 linux.bin 3100 3101* package compressed binary image for U-Boot: 3102 3103 mkimage -A ppc -O linux -T kernel -C gzip \ 3104 -a 0 -e 0 -n "Linux Kernel Image" \ 3105 -d linux.bin.gz uImage 3106 3107 3108The "mkimage" tool can also be used to create ramdisk images for use 3109with U-Boot, either separated from the Linux kernel image, or 3110combined into one file. "mkimage" encapsulates the images with a 64 3111byte header containing information about target architecture, 3112operating system, image type, compression method, entry points, time 3113stamp, CRC32 checksums, etc. 3114 3115"mkimage" can be called in two ways: to verify existing images and 3116print the header information, or to build new images. 3117 3118In the first form (with "-l" option) mkimage lists the information 3119contained in the header of an existing U-Boot image; this includes 3120checksum verification: 3121 3122 tools/mkimage -l image 3123 -l ==> list image header information 3124 3125The second form (with "-d" option) is used to build a U-Boot image 3126from a "data file" which is used as image payload: 3127 3128 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3129 -n name -d data_file image 3130 -A ==> set architecture to 'arch' 3131 -O ==> set operating system to 'os' 3132 -T ==> set image type to 'type' 3133 -C ==> set compression type 'comp' 3134 -a ==> set load address to 'addr' (hex) 3135 -e ==> set entry point to 'ep' (hex) 3136 -n ==> set image name to 'name' 3137 -d ==> use image data from 'datafile' 3138 3139Right now, all Linux kernels for PowerPC systems use the same load 3140address (0x00000000), but the entry point address depends on the 3141kernel version: 3142 3143- 2.2.x kernels have the entry point at 0x0000000C, 3144- 2.3.x and later kernels have the entry point at 0x00000000. 3145 3146So a typical call to build a U-Boot image would read: 3147 3148 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3149 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3150 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3151 > examples/uImage.TQM850L 3152 Image Name: 2.4.4 kernel for TQM850L 3153 Created: Wed Jul 19 02:34:59 2000 3154 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3155 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3156 Load Address: 0x00000000 3157 Entry Point: 0x00000000 3158 3159To verify the contents of the image (or check for corruption): 3160 3161 -> tools/mkimage -l examples/uImage.TQM850L 3162 Image Name: 2.4.4 kernel for TQM850L 3163 Created: Wed Jul 19 02:34:59 2000 3164 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3165 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3166 Load Address: 0x00000000 3167 Entry Point: 0x00000000 3168 3169NOTE: for embedded systems where boot time is critical you can trade 3170speed for memory and install an UNCOMPRESSED image instead: this 3171needs more space in Flash, but boots much faster since it does not 3172need to be uncompressed: 3173 3174 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3175 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3176 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3177 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3178 > examples/uImage.TQM850L-uncompressed 3179 Image Name: 2.4.4 kernel for TQM850L 3180 Created: Wed Jul 19 02:34:59 2000 3181 Image Type: PowerPC Linux Kernel Image (uncompressed) 3182 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3183 Load Address: 0x00000000 3184 Entry Point: 0x00000000 3185 3186 3187Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3188when your kernel is intended to use an initial ramdisk: 3189 3190 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3191 > -A ppc -O linux -T ramdisk -C gzip \ 3192 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3193 Image Name: Simple Ramdisk Image 3194 Created: Wed Jan 12 14:01:50 2000 3195 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3196 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3197 Load Address: 0x00000000 3198 Entry Point: 0x00000000 3199 3200 3201Installing a Linux Image: 3202------------------------- 3203 3204To downloading a U-Boot image over the serial (console) interface, 3205you must convert the image to S-Record format: 3206 3207 objcopy -I binary -O srec examples/image examples/image.srec 3208 3209The 'objcopy' does not understand the information in the U-Boot 3210image header, so the resulting S-Record file will be relative to 3211address 0x00000000. To load it to a given address, you need to 3212specify the target address as 'offset' parameter with the 'loads' 3213command. 3214 3215Example: install the image to address 0x40100000 (which on the 3216TQM8xxL is in the first Flash bank): 3217 3218 => erase 40100000 401FFFFF 3219 3220 .......... done 3221 Erased 8 sectors 3222 3223 => loads 40100000 3224 ## Ready for S-Record download ... 3225 ~>examples/image.srec 3226 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3227 ... 3228 15989 15990 15991 15992 3229 [file transfer complete] 3230 [connected] 3231 ## Start Addr = 0x00000000 3232 3233 3234You can check the success of the download using the 'iminfo' command; 3235this includes a checksum verification so you can be sure no data 3236corruption happened: 3237 3238 => imi 40100000 3239 3240 ## Checking Image at 40100000 ... 3241 Image Name: 2.2.13 for initrd on TQM850L 3242 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3243 Data Size: 335725 Bytes = 327 kB = 0 MB 3244 Load Address: 00000000 3245 Entry Point: 0000000c 3246 Verifying Checksum ... OK 3247 3248 3249Boot Linux: 3250----------- 3251 3252The "bootm" command is used to boot an application that is stored in 3253memory (RAM or Flash). In case of a Linux kernel image, the contents 3254of the "bootargs" environment variable is passed to the kernel as 3255parameters. You can check and modify this variable using the 3256"printenv" and "setenv" commands: 3257 3258 3259 => printenv bootargs 3260 bootargs=root=/dev/ram 3261 3262 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3263 3264 => printenv bootargs 3265 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3266 3267 => bootm 40020000 3268 ## Booting Linux kernel at 40020000 ... 3269 Image Name: 2.2.13 for NFS on TQM850L 3270 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3271 Data Size: 381681 Bytes = 372 kB = 0 MB 3272 Load Address: 00000000 3273 Entry Point: 0000000c 3274 Verifying Checksum ... OK 3275 Uncompressing Kernel Image ... OK 3276 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 3277 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3278 time_init: decrementer frequency = 187500000/60 3279 Calibrating delay loop... 49.77 BogoMIPS 3280 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3281 ... 3282 3283If you want to boot a Linux kernel with initial ram disk, you pass 3284the memory addresses of both the kernel and the initrd image (PPBCOOT 3285format!) to the "bootm" command: 3286 3287 => imi 40100000 40200000 3288 3289 ## Checking Image at 40100000 ... 3290 Image Name: 2.2.13 for initrd on TQM850L 3291 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3292 Data Size: 335725 Bytes = 327 kB = 0 MB 3293 Load Address: 00000000 3294 Entry Point: 0000000c 3295 Verifying Checksum ... OK 3296 3297 ## Checking Image at 40200000 ... 3298 Image Name: Simple Ramdisk Image 3299 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3300 Data Size: 566530 Bytes = 553 kB = 0 MB 3301 Load Address: 00000000 3302 Entry Point: 00000000 3303 Verifying Checksum ... OK 3304 3305 => bootm 40100000 40200000 3306 ## Booting Linux kernel at 40100000 ... 3307 Image Name: 2.2.13 for initrd on TQM850L 3308 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3309 Data Size: 335725 Bytes = 327 kB = 0 MB 3310 Load Address: 00000000 3311 Entry Point: 0000000c 3312 Verifying Checksum ... OK 3313 Uncompressing Kernel Image ... OK 3314 ## Loading RAMDisk Image at 40200000 ... 3315 Image Name: Simple Ramdisk Image 3316 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3317 Data Size: 566530 Bytes = 553 kB = 0 MB 3318 Load Address: 00000000 3319 Entry Point: 00000000 3320 Verifying Checksum ... OK 3321 Loading Ramdisk ... OK 3322 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 3323 Boot arguments: root=/dev/ram 3324 time_init: decrementer frequency = 187500000/60 3325 Calibrating delay loop... 49.77 BogoMIPS 3326 ... 3327 RAMDISK: Compressed image found at block 0 3328 VFS: Mounted root (ext2 filesystem). 3329 3330 bash# 3331 3332Boot Linux and pass a flat device tree: 3333----------- 3334 3335First, U-Boot must be compiled with the appropriate defines. See the section 3336titled "Linux Kernel Interface" above for a more in depth explanation. The 3337following is an example of how to start a kernel and pass an updated 3338flat device tree: 3339 3340=> print oftaddr 3341oftaddr=0x300000 3342=> print oft 3343oft=oftrees/mpc8540ads.dtb 3344=> tftp $oftaddr $oft 3345Speed: 1000, full duplex 3346Using TSEC0 device 3347TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3348Filename 'oftrees/mpc8540ads.dtb'. 3349Load address: 0x300000 3350Loading: # 3351done 3352Bytes transferred = 4106 (100a hex) 3353=> tftp $loadaddr $bootfile 3354Speed: 1000, full duplex 3355Using TSEC0 device 3356TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3357Filename 'uImage'. 3358Load address: 0x200000 3359Loading:############ 3360done 3361Bytes transferred = 1029407 (fb51f hex) 3362=> print loadaddr 3363loadaddr=200000 3364=> print oftaddr 3365oftaddr=0x300000 3366=> bootm $loadaddr - $oftaddr 3367## Booting image at 00200000 ... 3368 Image Name: Linux-2.6.17-dirty 3369 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3370 Data Size: 1029343 Bytes = 1005.2 kB 3371 Load Address: 00000000 3372 Entry Point: 00000000 3373 Verifying Checksum ... OK 3374 Uncompressing Kernel Image ... OK 3375Booting using flat device tree at 0x300000 3376Using MPC85xx ADS machine description 3377Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3378[snip] 3379 3380 3381More About U-Boot Image Types: 3382------------------------------ 3383 3384U-Boot supports the following image types: 3385 3386 "Standalone Programs" are directly runnable in the environment 3387 provided by U-Boot; it is expected that (if they behave 3388 well) you can continue to work in U-Boot after return from 3389 the Standalone Program. 3390 "OS Kernel Images" are usually images of some Embedded OS which 3391 will take over control completely. Usually these programs 3392 will install their own set of exception handlers, device 3393 drivers, set up the MMU, etc. - this means, that you cannot 3394 expect to re-enter U-Boot except by resetting the CPU. 3395 "RAMDisk Images" are more or less just data blocks, and their 3396 parameters (address, size) are passed to an OS kernel that is 3397 being started. 3398 "Multi-File Images" contain several images, typically an OS 3399 (Linux) kernel image and one or more data images like 3400 RAMDisks. This construct is useful for instance when you want 3401 to boot over the network using BOOTP etc., where the boot 3402 server provides just a single image file, but you want to get 3403 for instance an OS kernel and a RAMDisk image. 3404 3405 "Multi-File Images" start with a list of image sizes, each 3406 image size (in bytes) specified by an "uint32_t" in network 3407 byte order. This list is terminated by an "(uint32_t)0". 3408 Immediately after the terminating 0 follow the images, one by 3409 one, all aligned on "uint32_t" boundaries (size rounded up to 3410 a multiple of 4 bytes). 3411 3412 "Firmware Images" are binary images containing firmware (like 3413 U-Boot or FPGA images) which usually will be programmed to 3414 flash memory. 3415 3416 "Script files" are command sequences that will be executed by 3417 U-Boot's command interpreter; this feature is especially 3418 useful when you configure U-Boot to use a real shell (hush) 3419 as command interpreter. 3420 3421 3422Standalone HOWTO: 3423================= 3424 3425One of the features of U-Boot is that you can dynamically load and 3426run "standalone" applications, which can use some resources of 3427U-Boot like console I/O functions or interrupt services. 3428 3429Two simple examples are included with the sources: 3430 3431"Hello World" Demo: 3432------------------- 3433 3434'examples/hello_world.c' contains a small "Hello World" Demo 3435application; it is automatically compiled when you build U-Boot. 3436It's configured to run at address 0x00040004, so you can play with it 3437like that: 3438 3439 => loads 3440 ## Ready for S-Record download ... 3441 ~>examples/hello_world.srec 3442 1 2 3 4 5 6 7 8 9 10 11 ... 3443 [file transfer complete] 3444 [connected] 3445 ## Start Addr = 0x00040004 3446 3447 => go 40004 Hello World! This is a test. 3448 ## Starting application at 0x00040004 ... 3449 Hello World 3450 argc = 7 3451 argv[0] = "40004" 3452 argv[1] = "Hello" 3453 argv[2] = "World!" 3454 argv[3] = "This" 3455 argv[4] = "is" 3456 argv[5] = "a" 3457 argv[6] = "test." 3458 argv[7] = "<NULL>" 3459 Hit any key to exit ... 3460 3461 ## Application terminated, rc = 0x0 3462 3463Another example, which demonstrates how to register a CPM interrupt 3464handler with the U-Boot code, can be found in 'examples/timer.c'. 3465Here, a CPM timer is set up to generate an interrupt every second. 3466The interrupt service routine is trivial, just printing a '.' 3467character, but this is just a demo program. The application can be 3468controlled by the following keys: 3469 3470 ? - print current values og the CPM Timer registers 3471 b - enable interrupts and start timer 3472 e - stop timer and disable interrupts 3473 q - quit application 3474 3475 => loads 3476 ## Ready for S-Record download ... 3477 ~>examples/timer.srec 3478 1 2 3 4 5 6 7 8 9 10 11 ... 3479 [file transfer complete] 3480 [connected] 3481 ## Start Addr = 0x00040004 3482 3483 => go 40004 3484 ## Starting application at 0x00040004 ... 3485 TIMERS=0xfff00980 3486 Using timer 1 3487 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3488 3489Hit 'b': 3490 [q, b, e, ?] Set interval 1000000 us 3491 Enabling timer 3492Hit '?': 3493 [q, b, e, ?] ........ 3494 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3495Hit '?': 3496 [q, b, e, ?] . 3497 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3498Hit '?': 3499 [q, b, e, ?] . 3500 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3501Hit '?': 3502 [q, b, e, ?] . 3503 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3504Hit 'e': 3505 [q, b, e, ?] ...Stopping timer 3506Hit 'q': 3507 [q, b, e, ?] ## Application terminated, rc = 0x0 3508 3509 3510Minicom warning: 3511================ 3512 3513Over time, many people have reported problems when trying to use the 3514"minicom" terminal emulation program for serial download. I (wd) 3515consider minicom to be broken, and recommend not to use it. Under 3516Unix, I recommend to use C-Kermit for general purpose use (and 3517especially for kermit binary protocol download ("loadb" command), and 3518use "cu" for S-Record download ("loads" command). 3519 3520Nevertheless, if you absolutely want to use it try adding this 3521configuration to your "File transfer protocols" section: 3522 3523 Name Program Name U/D FullScr IO-Red. Multi 3524 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3525 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3526 3527 3528NetBSD Notes: 3529============= 3530 3531Starting at version 0.9.2, U-Boot supports NetBSD both as host 3532(build U-Boot) and target system (boots NetBSD/mpc8xx). 3533 3534Building requires a cross environment; it is known to work on 3535NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3536need gmake since the Makefiles are not compatible with BSD make). 3537Note that the cross-powerpc package does not install include files; 3538attempting to build U-Boot will fail because <machine/ansi.h> is 3539missing. This file has to be installed and patched manually: 3540 3541 # cd /usr/pkg/cross/powerpc-netbsd/include 3542 # mkdir powerpc 3543 # ln -s powerpc machine 3544 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3545 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3546 3547Native builds *don't* work due to incompatibilities between native 3548and U-Boot include files. 3549 3550Booting assumes that (the first part of) the image booted is a 3551stage-2 loader which in turn loads and then invokes the kernel 3552proper. Loader sources will eventually appear in the NetBSD source 3553tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3554meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3555 3556 3557Implementation Internals: 3558========================= 3559 3560The following is not intended to be a complete description of every 3561implementation detail. However, it should help to understand the 3562inner workings of U-Boot and make it easier to port it to custom 3563hardware. 3564 3565 3566Initial Stack, Global Data: 3567--------------------------- 3568 3569The implementation of U-Boot is complicated by the fact that U-Boot 3570starts running out of ROM (flash memory), usually without access to 3571system RAM (because the memory controller is not initialized yet). 3572This means that we don't have writable Data or BSS segments, and BSS 3573is not initialized as zero. To be able to get a C environment working 3574at all, we have to allocate at least a minimal stack. Implementation 3575options for this are defined and restricted by the CPU used: Some CPU 3576models provide on-chip memory (like the IMMR area on MPC8xx and 3577MPC826x processors), on others (parts of) the data cache can be 3578locked as (mis-) used as memory, etc. 3579 3580 Chris Hallinan posted a good summary of these issues to the 3581 u-boot-users mailing list: 3582 3583 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3584 From: "Chris Hallinan" <clh@net1plus.com> 3585 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3586 ... 3587 3588 Correct me if I'm wrong, folks, but the way I understand it 3589 is this: Using DCACHE as initial RAM for Stack, etc, does not 3590 require any physical RAM backing up the cache. The cleverness 3591 is that the cache is being used as a temporary supply of 3592 necessary storage before the SDRAM controller is setup. It's 3593 beyond the scope of this list to expain the details, but you 3594 can see how this works by studying the cache architecture and 3595 operation in the architecture and processor-specific manuals. 3596 3597 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3598 is another option for the system designer to use as an 3599 initial stack/ram area prior to SDRAM being available. Either 3600 option should work for you. Using CS 4 should be fine if your 3601 board designers haven't used it for something that would 3602 cause you grief during the initial boot! It is frequently not 3603 used. 3604 3605 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3606 with your processor/board/system design. The default value 3607 you will find in any recent u-boot distribution in 3608 walnut.h should work for you. I'd set it to a value larger 3609 than your SDRAM module. If you have a 64MB SDRAM module, set 3610 it above 400_0000. Just make sure your board has no resources 3611 that are supposed to respond to that address! That code in 3612 start.S has been around a while and should work as is when 3613 you get the config right. 3614 3615 -Chris Hallinan 3616 DS4.COM, Inc. 3617 3618It is essential to remember this, since it has some impact on the C 3619code for the initialization procedures: 3620 3621* Initialized global data (data segment) is read-only. Do not attempt 3622 to write it. 3623 3624* Do not use any unitialized global data (or implicitely initialized 3625 as zero data - BSS segment) at all - this is undefined, initiali- 3626 zation is performed later (when relocating to RAM). 3627 3628* Stack space is very limited. Avoid big data buffers or things like 3629 that. 3630 3631Having only the stack as writable memory limits means we cannot use 3632normal global data to share information beween the code. But it 3633turned out that the implementation of U-Boot can be greatly 3634simplified by making a global data structure (gd_t) available to all 3635functions. We could pass a pointer to this data as argument to _all_ 3636functions, but this would bloat the code. Instead we use a feature of 3637the GCC compiler (Global Register Variables) to share the data: we 3638place a pointer (gd) to the global data into a register which we 3639reserve for this purpose. 3640 3641When choosing a register for such a purpose we are restricted by the 3642relevant (E)ABI specifications for the current architecture, and by 3643GCC's implementation. 3644 3645For PowerPC, the following registers have specific use: 3646 R1: stack pointer 3647 R2: reserved for system use 3648 R3-R4: parameter passing and return values 3649 R5-R10: parameter passing 3650 R13: small data area pointer 3651 R30: GOT pointer 3652 R31: frame pointer 3653 3654 (U-Boot also uses R14 as internal GOT pointer.) 3655 3656 ==> U-Boot will use R2 to hold a pointer to the global data 3657 3658 Note: on PPC, we could use a static initializer (since the 3659 address of the global data structure is known at compile time), 3660 but it turned out that reserving a register results in somewhat 3661 smaller code - although the code savings are not that big (on 3662 average for all boards 752 bytes for the whole U-Boot image, 3663 624 text + 127 data). 3664 3665On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3666 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3667 3668 ==> U-Boot will use P5 to hold a pointer to the global data 3669 3670On ARM, the following registers are used: 3671 3672 R0: function argument word/integer result 3673 R1-R3: function argument word 3674 R9: GOT pointer 3675 R10: stack limit (used only if stack checking if enabled) 3676 R11: argument (frame) pointer 3677 R12: temporary workspace 3678 R13: stack pointer 3679 R14: link register 3680 R15: program counter 3681 3682 ==> U-Boot will use R8 to hold a pointer to the global data 3683 3684NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3685or current versions of GCC may "optimize" the code too much. 3686 3687Memory Management: 3688------------------ 3689 3690U-Boot runs in system state and uses physical addresses, i.e. the 3691MMU is not used either for address mapping nor for memory protection. 3692 3693The available memory is mapped to fixed addresses using the memory 3694controller. In this process, a contiguous block is formed for each 3695memory type (Flash, SDRAM, SRAM), even when it consists of several 3696physical memory banks. 3697 3698U-Boot is installed in the first 128 kB of the first Flash bank (on 3699TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3700booting and sizing and initializing DRAM, the code relocates itself 3701to the upper end of DRAM. Immediately below the U-Boot code some 3702memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3703configuration setting]. Below that, a structure with global Board 3704Info data is placed, followed by the stack (growing downward). 3705 3706Additionally, some exception handler code is copied to the low 8 kB 3707of DRAM (0x00000000 ... 0x00001FFF). 3708 3709So a typical memory configuration with 16 MB of DRAM could look like 3710this: 3711 3712 0x0000 0000 Exception Vector code 3713 : 3714 0x0000 1FFF 3715 0x0000 2000 Free for Application Use 3716 : 3717 : 3718 3719 : 3720 : 3721 0x00FB FF20 Monitor Stack (Growing downward) 3722 0x00FB FFAC Board Info Data and permanent copy of global data 3723 0x00FC 0000 Malloc Arena 3724 : 3725 0x00FD FFFF 3726 0x00FE 0000 RAM Copy of Monitor Code 3727 ... eventually: LCD or video framebuffer 3728 ... eventually: pRAM (Protected RAM - unchanged by reset) 3729 0x00FF FFFF [End of RAM] 3730 3731 3732System Initialization: 3733---------------------- 3734 3735In the reset configuration, U-Boot starts at the reset entry point 3736(on most PowerPC systens at address 0x00000100). Because of the reset 3737configuration for CS0# this is a mirror of the onboard Flash memory. 3738To be able to re-map memory U-Boot then jumps to its link address. 3739To be able to implement the initialization code in C, a (small!) 3740initial stack is set up in the internal Dual Ported RAM (in case CPUs 3741which provide such a feature like MPC8xx or MPC8260), or in a locked 3742part of the data cache. After that, U-Boot initializes the CPU core, 3743the caches and the SIU. 3744 3745Next, all (potentially) available memory banks are mapped using a 3746preliminary mapping. For example, we put them on 512 MB boundaries 3747(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3748on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3749programmed for SDRAM access. Using the temporary configuration, a 3750simple memory test is run that determines the size of the SDRAM 3751banks. 3752 3753When there is more than one SDRAM bank, and the banks are of 3754different size, the largest is mapped first. For equal size, the first 3755bank (CS2#) is mapped first. The first mapping is always for address 37560x00000000, with any additional banks following immediately to create 3757contiguous memory starting from 0. 3758 3759Then, the monitor installs itself at the upper end of the SDRAM area 3760and allocates memory for use by malloc() and for the global Board 3761Info data; also, the exception vector code is copied to the low RAM 3762pages, and the final stack is set up. 3763 3764Only after this relocation will you have a "normal" C environment; 3765until that you are restricted in several ways, mostly because you are 3766running from ROM, and because the code will have to be relocated to a 3767new address in RAM. 3768 3769 3770U-Boot Porting Guide: 3771---------------------- 3772 3773[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3774list, October 2002] 3775 3776 3777int main (int argc, char *argv[]) 3778{ 3779 sighandler_t no_more_time; 3780 3781 signal (SIGALRM, no_more_time); 3782 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3783 3784 if (available_money > available_manpower) { 3785 pay consultant to port U-Boot; 3786 return 0; 3787 } 3788 3789 Download latest U-Boot source; 3790 3791 Subscribe to u-boot-users mailing list; 3792 3793 if (clueless) { 3794 email ("Hi, I am new to U-Boot, how do I get started?"); 3795 } 3796 3797 while (learning) { 3798 Read the README file in the top level directory; 3799 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3800 Read the source, Luke; 3801 } 3802 3803 if (available_money > toLocalCurrency ($2500)) { 3804 Buy a BDI2000; 3805 } else { 3806 Add a lot of aggravation and time; 3807 } 3808 3809 Create your own board support subdirectory; 3810 3811 Create your own board config file; 3812 3813 while (!running) { 3814 do { 3815 Add / modify source code; 3816 } until (compiles); 3817 Debug; 3818 if (clueless) 3819 email ("Hi, I am having problems..."); 3820 } 3821 Send patch file to Wolfgang; 3822 3823 return 0; 3824} 3825 3826void no_more_time (int sig) 3827{ 3828 hire_a_guru(); 3829} 3830 3831 3832Coding Standards: 3833----------------- 3834 3835All contributions to U-Boot should conform to the Linux kernel 3836coding style; see the file "Documentation/CodingStyle" and the script 3837"scripts/Lindent" in your Linux kernel source directory. In sources 3838originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3839spaces before parameters to function calls) is actually used. 3840 3841Source files originating from a different project (for example the 3842MTD subsystem) are generally exempt from these guidelines and are not 3843reformated to ease subsequent migration to newer versions of those 3844sources. 3845 3846Please note that U-Boot is implemented in C (and to some small parts in 3847Assembler); no C++ is used, so please do not use C++ style comments (//) 3848in your code. 3849 3850Please also stick to the following formatting rules: 3851- remove any trailing white space 3852- use TAB characters for indentation, not spaces 3853- make sure NOT to use DOS '\r\n' line feeds 3854- do not add more than 2 empty lines to source files 3855- do not add trailing empty lines to source files 3856 3857Submissions which do not conform to the standards may be returned 3858with a request to reformat the changes. 3859 3860 3861Submitting Patches: 3862------------------- 3863 3864Since the number of patches for U-Boot is growing, we need to 3865establish some rules. Submissions which do not conform to these rules 3866may be rejected, even when they contain important and valuable stuff. 3867 3868Patches shall be sent to the u-boot-users mailing list. 3869 3870Please see http://www.denx.de/wiki/UBoot/Patches for details. 3871 3872When you send a patch, please include the following information with 3873it: 3874 3875* For bug fixes: a description of the bug and how your patch fixes 3876 this bug. Please try to include a way of demonstrating that the 3877 patch actually fixes something. 3878 3879* For new features: a description of the feature and your 3880 implementation. 3881 3882* A CHANGELOG entry as plaintext (separate from the patch) 3883 3884* For major contributions, your entry to the CREDITS file 3885 3886* When you add support for a new board, don't forget to add this 3887 board to the MAKEALL script, too. 3888 3889* If your patch adds new configuration options, don't forget to 3890 document these in the README file. 3891 3892* The patch itself. If you are using git (which is *strongly* 3893 recommended) you can easily generate the patch using the 3894 "git-format-patch". If you then use "git-send-email" to send it to 3895 the U-Boot mailing list, you will avoid most of the common problems 3896 with some other mail clients. 3897 3898 If you cannot use git, use "diff -purN OLD NEW". If your version of 3899 diff does not support these options, then get the latest version of 3900 GNU diff. 3901 3902 The current directory when running this command shall be the parent 3903 directory of the U-Boot source tree (i. e. please make sure that 3904 your patch includes sufficient directory information for the 3905 affected files). 3906 3907 We prefer patches as plain text. MIME attachments are discouraged, 3908 and compressed attachments must not be used. 3909 3910* If one logical set of modifications affects or creates several 3911 files, all these changes shall be submitted in a SINGLE patch file. 3912 3913* Changesets that contain different, unrelated modifications shall be 3914 submitted as SEPARATE patches, one patch per changeset. 3915 3916 3917Notes: 3918 3919* Before sending the patch, run the MAKEALL script on your patched 3920 source tree and make sure that no errors or warnings are reported 3921 for any of the boards. 3922 3923* Keep your modifications to the necessary minimum: A patch 3924 containing several unrelated changes or arbitrary reformats will be 3925 returned with a request to re-formatting / split it. 3926 3927* If you modify existing code, make sure that your new code does not 3928 add to the memory footprint of the code ;-) Small is beautiful! 3929 When adding new features, these should compile conditionally only 3930 (using #ifdef), and the resulting code with the new feature 3931 disabled must not need more memory than the old code without your 3932 modification. 3933 3934* Remember that there is a size limit of 40 kB per message on the 3935 u-boot-users mailing list. Bigger patches will be moderated. If 3936 they are reasonable and not bigger than 100 kB, they will be 3937 acknowledged. Even bigger patches should be avoided. 3938