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_EEPRO100 755 Support for Intel 82557/82559/82559ER chips. 756 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 757 write routine for first time initialisation. 758 759 CONFIG_TULIP 760 Support for Digital 2114x chips. 761 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 762 modem chip initialisation (KS8761/QS6611). 763 764 CONFIG_NATSEMI 765 Support for National dp83815 chips. 766 767 CONFIG_NS8382X 768 Support for National dp8382[01] gigabit chips. 769 770- NETWORK Support (other): 771 772 CONFIG_DRIVER_LAN91C96 773 Support for SMSC's LAN91C96 chips. 774 775 CONFIG_LAN91C96_BASE 776 Define this to hold the physical address 777 of the LAN91C96's I/O space 778 779 CONFIG_LAN91C96_USE_32_BIT 780 Define this to enable 32 bit addressing 781 782 CONFIG_DRIVER_SMC91111 783 Support for SMSC's LAN91C111 chip 784 785 CONFIG_SMC91111_BASE 786 Define this to hold the physical address 787 of the device (I/O space) 788 789 CONFIG_SMC_USE_32_BIT 790 Define this if data bus is 32 bits 791 792 CONFIG_SMC_USE_IOFUNCS 793 Define this to use i/o functions instead of macros 794 (some hardware wont work with macros) 795 796- USB Support: 797 At the moment only the UHCI host controller is 798 supported (PIP405, MIP405, MPC5200); define 799 CONFIG_USB_UHCI to enable it. 800 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 801 and define CONFIG_USB_STORAGE to enable the USB 802 storage devices. 803 Note: 804 Supported are USB Keyboards and USB Floppy drives 805 (TEAC FD-05PUB). 806 MPC5200 USB requires additional defines: 807 CONFIG_USB_CLOCK 808 for 528 MHz Clock: 0x0001bbbb 809 CONFIG_USB_CONFIG 810 for differential drivers: 0x00001000 811 for single ended drivers: 0x00005000 812 CFG_USB_EVENT_POLL 813 May be defined to allow interrupt polling 814 instead of using asynchronous interrupts 815 816- USB Device: 817 Define the below if you wish to use the USB console. 818 Once firmware is rebuilt from a serial console issue the 819 command "setenv stdin usbtty; setenv stdout usbtty" and 820 attach your usb cable. The Unix command "dmesg" should print 821 it has found a new device. The environment variable usbtty 822 can be set to gserial or cdc_acm to enable your device to 823 appear to a USB host as a Linux gserial device or a 824 Common Device Class Abstract Control Model serial device. 825 If you select usbtty = gserial you should be able to enumerate 826 a Linux host by 827 # modprobe usbserial vendor=0xVendorID product=0xProductID 828 else if using cdc_acm, simply setting the environment 829 variable usbtty to be cdc_acm should suffice. The following 830 might be defined in YourBoardName.h 831 832 CONFIG_USB_DEVICE 833 Define this to build a UDC device 834 835 CONFIG_USB_TTY 836 Define this to have a tty type of device available to 837 talk to the UDC device 838 839 CFG_CONSOLE_IS_IN_ENV 840 Define this if you want stdin, stdout &/or stderr to 841 be set to usbtty. 842 843 mpc8xx: 844 CFG_USB_EXTC_CLK 0xBLAH 845 Derive USB clock from external clock "blah" 846 - CFG_USB_EXTC_CLK 0x02 847 848 CFG_USB_BRG_CLK 0xBLAH 849 Derive USB clock from brgclk 850 - CFG_USB_BRG_CLK 0x04 851 852 If you have a USB-IF assigned VendorID then you may wish to 853 define your own vendor specific values either in BoardName.h 854 or directly in usbd_vendor_info.h. If you don't define 855 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 856 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 857 should pretend to be a Linux device to it's target host. 858 859 CONFIG_USBD_MANUFACTURER 860 Define this string as the name of your company for 861 - CONFIG_USBD_MANUFACTURER "my company" 862 863 CONFIG_USBD_PRODUCT_NAME 864 Define this string as the name of your product 865 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 866 867 CONFIG_USBD_VENDORID 868 Define this as your assigned Vendor ID from the USB 869 Implementors Forum. This *must* be a genuine Vendor ID 870 to avoid polluting the USB namespace. 871 - CONFIG_USBD_VENDORID 0xFFFF 872 873 CONFIG_USBD_PRODUCTID 874 Define this as the unique Product ID 875 for your device 876 - CONFIG_USBD_PRODUCTID 0xFFFF 877 878 879- MMC Support: 880 The MMC controller on the Intel PXA is supported. To 881 enable this define CONFIG_MMC. The MMC can be 882 accessed from the boot prompt by mapping the device 883 to physical memory similar to flash. Command line is 884 enabled with CONFIG_CMD_MMC. The MMC driver also works with 885 the FAT fs. This is enabled with CONFIG_CMD_FAT. 886 887- Journaling Flash filesystem support: 888 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 889 CONFIG_JFFS2_NAND_DEV 890 Define these for a default partition on a NAND device 891 892 CFG_JFFS2_FIRST_SECTOR, 893 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 894 Define these for a default partition on a NOR device 895 896 CFG_JFFS_CUSTOM_PART 897 Define this to create an own partition. You have to provide a 898 function struct part_info* jffs2_part_info(int part_num) 899 900 If you define only one JFFS2 partition you may also want to 901 #define CFG_JFFS_SINGLE_PART 1 902 to disable the command chpart. This is the default when you 903 have not defined a custom partition 904 905- Keyboard Support: 906 CONFIG_ISA_KEYBOARD 907 908 Define this to enable standard (PC-Style) keyboard 909 support 910 911 CONFIG_I8042_KBD 912 Standard PC keyboard driver with US (is default) and 913 GERMAN key layout (switch via environment 'keymap=de') support. 914 Export function i8042_kbd_init, i8042_tstc and i8042_getc 915 for cfb_console. Supports cursor blinking. 916 917- Video support: 918 CONFIG_VIDEO 919 920 Define this to enable video support (for output to 921 video). 922 923 CONFIG_VIDEO_CT69000 924 925 Enable Chips & Technologies 69000 Video chip 926 927 CONFIG_VIDEO_SMI_LYNXEM 928 Enable Silicon Motion SMI 712/710/810 Video chip. The 929 video output is selected via environment 'videoout' 930 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 931 assumed. 932 933 For the CT69000 and SMI_LYNXEM drivers, videomode is 934 selected via environment 'videomode'. Two diferent ways 935 are possible: 936 - "videomode=num" 'num' is a standard LiLo mode numbers. 937 Following standard modes are supported (* is default): 938 939 Colors 640x480 800x600 1024x768 1152x864 1280x1024 940 -------------+--------------------------------------------- 941 8 bits | 0x301* 0x303 0x305 0x161 0x307 942 15 bits | 0x310 0x313 0x316 0x162 0x319 943 16 bits | 0x311 0x314 0x317 0x163 0x31A 944 24 bits | 0x312 0x315 0x318 ? 0x31B 945 -------------+--------------------------------------------- 946 (i.e. setenv videomode 317; saveenv; reset;) 947 948 - "videomode=bootargs" all the video parameters are parsed 949 from the bootargs. (See drivers/video/videomodes.c) 950 951 952 CONFIG_VIDEO_SED13806 953 Enable Epson SED13806 driver. This driver supports 8bpp 954 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 955 or CONFIG_VIDEO_SED13806_16BPP 956 957- Keyboard Support: 958 CONFIG_KEYBOARD 959 960 Define this to enable a custom keyboard support. 961 This simply calls drv_keyboard_init() which must be 962 defined in your board-specific files. 963 The only board using this so far is RBC823. 964 965- LCD Support: CONFIG_LCD 966 967 Define this to enable LCD support (for output to LCD 968 display); also select one of the supported displays 969 by defining one of these: 970 971 CONFIG_NEC_NL6448AC33: 972 973 NEC NL6448AC33-18. Active, color, single scan. 974 975 CONFIG_NEC_NL6448BC20 976 977 NEC NL6448BC20-08. 6.5", 640x480. 978 Active, color, single scan. 979 980 CONFIG_NEC_NL6448BC33_54 981 982 NEC NL6448BC33-54. 10.4", 640x480. 983 Active, color, single scan. 984 985 CONFIG_SHARP_16x9 986 987 Sharp 320x240. Active, color, single scan. 988 It isn't 16x9, and I am not sure what it is. 989 990 CONFIG_SHARP_LQ64D341 991 992 Sharp LQ64D341 display, 640x480. 993 Active, color, single scan. 994 995 CONFIG_HLD1045 996 997 HLD1045 display, 640x480. 998 Active, color, single scan. 999 1000 CONFIG_OPTREX_BW 1001 1002 Optrex CBL50840-2 NF-FW 99 22 M5 1003 or 1004 Hitachi LMG6912RPFC-00T 1005 or 1006 Hitachi SP14Q002 1007 1008 320x240. Black & white. 1009 1010 Normally display is black on white background; define 1011 CFG_WHITE_ON_BLACK to get it inverted. 1012 1013- Splash Screen Support: CONFIG_SPLASH_SCREEN 1014 1015 If this option is set, the environment is checked for 1016 a variable "splashimage". If found, the usual display 1017 of logo, copyright and system information on the LCD 1018 is suppressed and the BMP image at the address 1019 specified in "splashimage" is loaded instead. The 1020 console is redirected to the "nulldev", too. This 1021 allows for a "silent" boot where a splash screen is 1022 loaded very quickly after power-on. 1023 1024- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1025 1026 If this option is set, additionally to standard BMP 1027 images, gzipped BMP images can be displayed via the 1028 splashscreen support or the bmp command. 1029 1030- Compression support: 1031 CONFIG_BZIP2 1032 1033 If this option is set, support for bzip2 compressed 1034 images is included. If not, only uncompressed and gzip 1035 compressed images are supported. 1036 1037 NOTE: the bzip2 algorithm requires a lot of RAM, so 1038 the malloc area (as defined by CFG_MALLOC_LEN) should 1039 be at least 4MB. 1040 1041- MII/PHY support: 1042 CONFIG_PHY_ADDR 1043 1044 The address of PHY on MII bus. 1045 1046 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1047 1048 The clock frequency of the MII bus 1049 1050 CONFIG_PHY_GIGE 1051 1052 If this option is set, support for speed/duplex 1053 detection of Gigabit PHY is included. 1054 1055 CONFIG_PHY_RESET_DELAY 1056 1057 Some PHY like Intel LXT971A need extra delay after 1058 reset before any MII register access is possible. 1059 For such PHY, set this option to the usec delay 1060 required. (minimum 300usec for LXT971A) 1061 1062 CONFIG_PHY_CMD_DELAY (ppc4xx) 1063 1064 Some PHY like Intel LXT971A need extra delay after 1065 command issued before MII status register can be read 1066 1067- Ethernet address: 1068 CONFIG_ETHADDR 1069 CONFIG_ETH2ADDR 1070 CONFIG_ETH3ADDR 1071 1072 Define a default value for ethernet address to use 1073 for the respective ethernet interface, in case this 1074 is not determined automatically. 1075 1076- IP address: 1077 CONFIG_IPADDR 1078 1079 Define a default value for the IP address to use for 1080 the default ethernet interface, in case this is not 1081 determined through e.g. bootp. 1082 1083- Server IP address: 1084 CONFIG_SERVERIP 1085 1086 Defines a default value for theIP address of a TFTP 1087 server to contact when using the "tftboot" command. 1088 1089- Multicast TFTP Mode: 1090 CONFIG_MCAST_TFTP 1091 1092 Defines whether you want to support multicast TFTP as per 1093 rfc-2090; for example to work with atftp. Lets lots of targets 1094 tftp down the same boot image concurrently. Note: the ethernet 1095 driver in use must provide a function: mcast() to join/leave a 1096 multicast group. 1097 1098 CONFIG_BOOTP_RANDOM_DELAY 1099- BOOTP Recovery Mode: 1100 CONFIG_BOOTP_RANDOM_DELAY 1101 1102 If you have many targets in a network that try to 1103 boot using BOOTP, you may want to avoid that all 1104 systems send out BOOTP requests at precisely the same 1105 moment (which would happen for instance at recovery 1106 from a power failure, when all systems will try to 1107 boot, thus flooding the BOOTP server. Defining 1108 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1109 inserted before sending out BOOTP requests. The 1110 following delays are inserted then: 1111 1112 1st BOOTP request: delay 0 ... 1 sec 1113 2nd BOOTP request: delay 0 ... 2 sec 1114 3rd BOOTP request: delay 0 ... 4 sec 1115 4th and following 1116 BOOTP requests: delay 0 ... 8 sec 1117 1118- DHCP Advanced Options: 1119 You can fine tune the DHCP functionality by defining 1120 CONFIG_BOOTP_* symbols: 1121 1122 CONFIG_BOOTP_SUBNETMASK 1123 CONFIG_BOOTP_GATEWAY 1124 CONFIG_BOOTP_HOSTNAME 1125 CONFIG_BOOTP_NISDOMAIN 1126 CONFIG_BOOTP_BOOTPATH 1127 CONFIG_BOOTP_BOOTFILESIZE 1128 CONFIG_BOOTP_DNS 1129 CONFIG_BOOTP_DNS2 1130 CONFIG_BOOTP_SEND_HOSTNAME 1131 CONFIG_BOOTP_NTPSERVER 1132 CONFIG_BOOTP_TIMEOFFSET 1133 CONFIG_BOOTP_VENDOREX 1134 1135 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1136 environment variable, not the BOOTP server. 1137 1138 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1139 serverip from a DHCP server, it is possible that more 1140 than one DNS serverip is offered to the client. 1141 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1142 serverip will be stored in the additional environment 1143 variable "dnsip2". The first DNS serverip is always 1144 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1145 is defined. 1146 1147 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1148 to do a dynamic update of a DNS server. To do this, they 1149 need the hostname of the DHCP requester. 1150 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1151 of the "hostname" environment variable is passed as 1152 option 12 to the DHCP server. 1153 1154 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1155 1156 A 32bit value in microseconds for a delay between 1157 receiving a "DHCP Offer" and sending the "DHCP Request". 1158 This fixes a problem with certain DHCP servers that don't 1159 respond 100% of the time to a "DHCP request". E.g. On an 1160 AT91RM9200 processor running at 180MHz, this delay needed 1161 to be *at least* 15,000 usec before a Windows Server 2003 1162 DHCP server would reply 100% of the time. I recommend at 1163 least 50,000 usec to be safe. The alternative is to hope 1164 that one of the retries will be successful but note that 1165 the DHCP timeout and retry process takes a longer than 1166 this delay. 1167 1168 - CDP Options: 1169 CONFIG_CDP_DEVICE_ID 1170 1171 The device id used in CDP trigger frames. 1172 1173 CONFIG_CDP_DEVICE_ID_PREFIX 1174 1175 A two character string which is prefixed to the MAC address 1176 of the device. 1177 1178 CONFIG_CDP_PORT_ID 1179 1180 A printf format string which contains the ascii name of 1181 the port. Normally is set to "eth%d" which sets 1182 eth0 for the first ethernet, eth1 for the second etc. 1183 1184 CONFIG_CDP_CAPABILITIES 1185 1186 A 32bit integer which indicates the device capabilities; 1187 0x00000010 for a normal host which does not forwards. 1188 1189 CONFIG_CDP_VERSION 1190 1191 An ascii string containing the version of the software. 1192 1193 CONFIG_CDP_PLATFORM 1194 1195 An ascii string containing the name of the platform. 1196 1197 CONFIG_CDP_TRIGGER 1198 1199 A 32bit integer sent on the trigger. 1200 1201 CONFIG_CDP_POWER_CONSUMPTION 1202 1203 A 16bit integer containing the power consumption of the 1204 device in .1 of milliwatts. 1205 1206 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1207 1208 A byte containing the id of the VLAN. 1209 1210- Status LED: CONFIG_STATUS_LED 1211 1212 Several configurations allow to display the current 1213 status using a LED. For instance, the LED will blink 1214 fast while running U-Boot code, stop blinking as 1215 soon as a reply to a BOOTP request was received, and 1216 start blinking slow once the Linux kernel is running 1217 (supported by a status LED driver in the Linux 1218 kernel). Defining CONFIG_STATUS_LED enables this 1219 feature in U-Boot. 1220 1221- CAN Support: CONFIG_CAN_DRIVER 1222 1223 Defining CONFIG_CAN_DRIVER enables CAN driver support 1224 on those systems that support this (optional) 1225 feature, like the TQM8xxL modules. 1226 1227- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1228 1229 These enable I2C serial bus commands. Defining either of 1230 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1231 include the appropriate I2C driver for the selected cpu. 1232 1233 This will allow you to use i2c commands at the u-boot 1234 command line (as long as you set CONFIG_CMD_I2C in 1235 CONFIG_COMMANDS) and communicate with i2c based realtime 1236 clock chips. See common/cmd_i2c.c for a description of the 1237 command line interface. 1238 1239 CONFIG_I2C_CMD_TREE is a recommended option that places 1240 all I2C commands under a single 'i2c' root command. The 1241 older 'imm', 'imd', 'iprobe' etc. commands are considered 1242 deprecated and may disappear in the future. 1243 1244 CONFIG_HARD_I2C selects a hardware I2C controller. 1245 1246 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1247 bit-banging) driver instead of CPM or similar hardware 1248 support for I2C. 1249 1250 There are several other quantities that must also be 1251 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1252 1253 In both cases you will need to define CFG_I2C_SPEED 1254 to be the frequency (in Hz) at which you wish your i2c bus 1255 to run and CFG_I2C_SLAVE to be the address of this node (ie 1256 the cpu's i2c node address). 1257 1258 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1259 sets the cpu up as a master node and so its address should 1260 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1261 p.16-473). So, set CFG_I2C_SLAVE to 0. 1262 1263 That's all that's required for CONFIG_HARD_I2C. 1264 1265 If you use the software i2c interface (CONFIG_SOFT_I2C) 1266 then the following macros need to be defined (examples are 1267 from include/configs/lwmon.h): 1268 1269 I2C_INIT 1270 1271 (Optional). Any commands necessary to enable the I2C 1272 controller or configure ports. 1273 1274 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1275 1276 I2C_PORT 1277 1278 (Only for MPC8260 CPU). The I/O port to use (the code 1279 assumes both bits are on the same port). Valid values 1280 are 0..3 for ports A..D. 1281 1282 I2C_ACTIVE 1283 1284 The code necessary to make the I2C data line active 1285 (driven). If the data line is open collector, this 1286 define can be null. 1287 1288 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1289 1290 I2C_TRISTATE 1291 1292 The code necessary to make the I2C data line tri-stated 1293 (inactive). If the data line is open collector, this 1294 define can be null. 1295 1296 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1297 1298 I2C_READ 1299 1300 Code that returns TRUE if the I2C data line is high, 1301 FALSE if it is low. 1302 1303 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1304 1305 I2C_SDA(bit) 1306 1307 If <bit> is TRUE, sets the I2C data line high. If it 1308 is FALSE, it clears it (low). 1309 1310 eg: #define I2C_SDA(bit) \ 1311 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1312 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1313 1314 I2C_SCL(bit) 1315 1316 If <bit> is TRUE, sets the I2C clock line high. If it 1317 is FALSE, it clears it (low). 1318 1319 eg: #define I2C_SCL(bit) \ 1320 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1321 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1322 1323 I2C_DELAY 1324 1325 This delay is invoked four times per clock cycle so this 1326 controls the rate of data transfer. The data rate thus 1327 is 1 / (I2C_DELAY * 4). Often defined to be something 1328 like: 1329 1330 #define I2C_DELAY udelay(2) 1331 1332 CFG_I2C_INIT_BOARD 1333 1334 When a board is reset during an i2c bus transfer 1335 chips might think that the current transfer is still 1336 in progress. On some boards it is possible to access 1337 the i2c SCLK line directly, either by using the 1338 processor pin as a GPIO or by having a second pin 1339 connected to the bus. If this option is defined a 1340 custom i2c_init_board() routine in boards/xxx/board.c 1341 is run early in the boot sequence. 1342 1343 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1344 1345 This option enables configuration of bi_iic_fast[] flags 1346 in u-boot bd_info structure based on u-boot environment 1347 variable "i2cfast". (see also i2cfast) 1348 1349 CONFIG_I2C_MULTI_BUS 1350 1351 This option allows the use of multiple I2C buses, each of which 1352 must have a controller. At any point in time, only one bus is 1353 active. To switch to a different bus, use the 'i2c dev' command. 1354 Note that bus numbering is zero-based. 1355 1356 CFG_I2C_NOPROBES 1357 1358 This option specifies a list of I2C devices that will be skipped 1359 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1360 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1361 pairs. Otherwise, specify a 1D array of device addresses 1362 1363 e.g. 1364 #undef CONFIG_I2C_MULTI_BUS 1365 #define CFG_I2C_NOPROBES {0x50,0x68} 1366 1367 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1368 1369 #define CONFIG_I2C_MULTI_BUS 1370 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1371 1372 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1373 1374 CFG_SPD_BUS_NUM 1375 1376 If defined, then this indicates the I2C bus number for DDR SPD. 1377 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1378 1379 CFG_RTC_BUS_NUM 1380 1381 If defined, then this indicates the I2C bus number for the RTC. 1382 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1383 1384 CFG_DTT_BUS_NUM 1385 1386 If defined, then this indicates the I2C bus number for the DTT. 1387 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1388 1389 CONFIG_FSL_I2C 1390 1391 Define this option if you want to use Freescale's I2C driver in 1392 drivers/i2c/fsl_i2c.c. 1393 1394 1395- SPI Support: CONFIG_SPI 1396 1397 Enables SPI driver (so far only tested with 1398 SPI EEPROM, also an instance works with Crystal A/D and 1399 D/As on the SACSng board) 1400 1401 CONFIG_SPI_X 1402 1403 Enables extended (16-bit) SPI EEPROM addressing. 1404 (symmetrical to CONFIG_I2C_X) 1405 1406 CONFIG_SOFT_SPI 1407 1408 Enables a software (bit-bang) SPI driver rather than 1409 using hardware support. This is a general purpose 1410 driver that only requires three general I/O port pins 1411 (two outputs, one input) to function. If this is 1412 defined, the board configuration must define several 1413 SPI configuration items (port pins to use, etc). For 1414 an example, see include/configs/sacsng.h. 1415 1416 CONFIG_HARD_SPI 1417 1418 Enables a hardware SPI driver for general-purpose reads 1419 and writes. As with CONFIG_SOFT_SPI, the board configuration 1420 must define a list of chip-select function pointers. 1421 Currently supported on some MPC8xxx processors. For an 1422 example, see include/configs/mpc8349emds.h. 1423 1424- FPGA Support: CONFIG_FPGA 1425 1426 Enables FPGA subsystem. 1427 1428 CONFIG_FPGA_<vendor> 1429 1430 Enables support for specific chip vendors. 1431 (ALTERA, XILINX) 1432 1433 CONFIG_FPGA_<family> 1434 1435 Enables support for FPGA family. 1436 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1437 1438 CONFIG_FPGA_COUNT 1439 1440 Specify the number of FPGA devices to support. 1441 1442 CFG_FPGA_PROG_FEEDBACK 1443 1444 Enable printing of hash marks during FPGA configuration. 1445 1446 CFG_FPGA_CHECK_BUSY 1447 1448 Enable checks on FPGA configuration interface busy 1449 status by the configuration function. This option 1450 will require a board or device specific function to 1451 be written. 1452 1453 CONFIG_FPGA_DELAY 1454 1455 If defined, a function that provides delays in the FPGA 1456 configuration driver. 1457 1458 CFG_FPGA_CHECK_CTRLC 1459 Allow Control-C to interrupt FPGA configuration 1460 1461 CFG_FPGA_CHECK_ERROR 1462 1463 Check for configuration errors during FPGA bitfile 1464 loading. For example, abort during Virtex II 1465 configuration if the INIT_B line goes low (which 1466 indicated a CRC error). 1467 1468 CFG_FPGA_WAIT_INIT 1469 1470 Maximum time to wait for the INIT_B line to deassert 1471 after PROB_B has been deasserted during a Virtex II 1472 FPGA configuration sequence. The default time is 500 1473 mS. 1474 1475 CFG_FPGA_WAIT_BUSY 1476 1477 Maximum time to wait for BUSY to deassert during 1478 Virtex II FPGA configuration. The default is 5 mS. 1479 1480 CFG_FPGA_WAIT_CONFIG 1481 1482 Time to wait after FPGA configuration. The default is 1483 200 mS. 1484 1485- Configuration Management: 1486 CONFIG_IDENT_STRING 1487 1488 If defined, this string will be added to the U-Boot 1489 version information (U_BOOT_VERSION) 1490 1491- Vendor Parameter Protection: 1492 1493 U-Boot considers the values of the environment 1494 variables "serial#" (Board Serial Number) and 1495 "ethaddr" (Ethernet Address) to be parameters that 1496 are set once by the board vendor / manufacturer, and 1497 protects these variables from casual modification by 1498 the user. Once set, these variables are read-only, 1499 and write or delete attempts are rejected. You can 1500 change this behviour: 1501 1502 If CONFIG_ENV_OVERWRITE is #defined in your config 1503 file, the write protection for vendor parameters is 1504 completely disabled. Anybody can change or delete 1505 these parameters. 1506 1507 Alternatively, if you #define _both_ CONFIG_ETHADDR 1508 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1509 ethernet address is installed in the environment, 1510 which can be changed exactly ONCE by the user. [The 1511 serial# is unaffected by this, i. e. it remains 1512 read-only.] 1513 1514- Protected RAM: 1515 CONFIG_PRAM 1516 1517 Define this variable to enable the reservation of 1518 "protected RAM", i. e. RAM which is not overwritten 1519 by U-Boot. Define CONFIG_PRAM to hold the number of 1520 kB you want to reserve for pRAM. You can overwrite 1521 this default value by defining an environment 1522 variable "pram" to the number of kB you want to 1523 reserve. Note that the board info structure will 1524 still show the full amount of RAM. If pRAM is 1525 reserved, a new environment variable "mem" will 1526 automatically be defined to hold the amount of 1527 remaining RAM in a form that can be passed as boot 1528 argument to Linux, for instance like that: 1529 1530 setenv bootargs ... mem=\${mem} 1531 saveenv 1532 1533 This way you can tell Linux not to use this memory, 1534 either, which results in a memory region that will 1535 not be affected by reboots. 1536 1537 *WARNING* If your board configuration uses automatic 1538 detection of the RAM size, you must make sure that 1539 this memory test is non-destructive. So far, the 1540 following board configurations are known to be 1541 "pRAM-clean": 1542 1543 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1544 HERMES, IP860, RPXlite, LWMON, LANTEC, 1545 PCU_E, FLAGADM, TQM8260 1546 1547- Error Recovery: 1548 CONFIG_PANIC_HANG 1549 1550 Define this variable to stop the system in case of a 1551 fatal error, so that you have to reset it manually. 1552 This is probably NOT a good idea for an embedded 1553 system where you want to system to reboot 1554 automatically as fast as possible, but it may be 1555 useful during development since you can try to debug 1556 the conditions that lead to the situation. 1557 1558 CONFIG_NET_RETRY_COUNT 1559 1560 This variable defines the number of retries for 1561 network operations like ARP, RARP, TFTP, or BOOTP 1562 before giving up the operation. If not defined, a 1563 default value of 5 is used. 1564 1565- Command Interpreter: 1566 CONFIG_AUTO_COMPLETE 1567 1568 Enable auto completion of commands using TAB. 1569 1570 Note that this feature has NOT been implemented yet 1571 for the "hush" shell. 1572 1573 1574 CFG_HUSH_PARSER 1575 1576 Define this variable to enable the "hush" shell (from 1577 Busybox) as command line interpreter, thus enabling 1578 powerful command line syntax like 1579 if...then...else...fi conditionals or `&&' and '||' 1580 constructs ("shell scripts"). 1581 1582 If undefined, you get the old, much simpler behaviour 1583 with a somewhat smaller memory footprint. 1584 1585 1586 CFG_PROMPT_HUSH_PS2 1587 1588 This defines the secondary prompt string, which is 1589 printed when the command interpreter needs more input 1590 to complete a command. Usually "> ". 1591 1592 Note: 1593 1594 In the current implementation, the local variables 1595 space and global environment variables space are 1596 separated. Local variables are those you define by 1597 simply typing `name=value'. To access a local 1598 variable later on, you have write `$name' or 1599 `${name}'; to execute the contents of a variable 1600 directly type `$name' at the command prompt. 1601 1602 Global environment variables are those you use 1603 setenv/printenv to work with. To run a command stored 1604 in such a variable, you need to use the run command, 1605 and you must not use the '$' sign to access them. 1606 1607 To store commands and special characters in a 1608 variable, please use double quotation marks 1609 surrounding the whole text of the variable, instead 1610 of the backslashes before semicolons and special 1611 symbols. 1612 1613- Commandline Editing and History: 1614 CONFIG_CMDLINE_EDITING 1615 1616 Enable editiong and History functions for interactive 1617 commandline input operations 1618 1619- Default Environment: 1620 CONFIG_EXTRA_ENV_SETTINGS 1621 1622 Define this to contain any number of null terminated 1623 strings (variable = value pairs) that will be part of 1624 the default environment compiled into the boot image. 1625 1626 For example, place something like this in your 1627 board's config file: 1628 1629 #define CONFIG_EXTRA_ENV_SETTINGS \ 1630 "myvar1=value1\0" \ 1631 "myvar2=value2\0" 1632 1633 Warning: This method is based on knowledge about the 1634 internal format how the environment is stored by the 1635 U-Boot code. This is NOT an official, exported 1636 interface! Although it is unlikely that this format 1637 will change soon, there is no guarantee either. 1638 You better know what you are doing here. 1639 1640 Note: overly (ab)use of the default environment is 1641 discouraged. Make sure to check other ways to preset 1642 the environment like the autoscript function or the 1643 boot command first. 1644 1645- DataFlash Support: 1646 CONFIG_HAS_DATAFLASH 1647 1648 Defining this option enables DataFlash features and 1649 allows to read/write in Dataflash via the standard 1650 commands cp, md... 1651 1652- SystemACE Support: 1653 CONFIG_SYSTEMACE 1654 1655 Adding this option adds support for Xilinx SystemACE 1656 chips attached via some sort of local bus. The address 1657 of the chip must alsh be defined in the 1658 CFG_SYSTEMACE_BASE macro. For example: 1659 1660 #define CONFIG_SYSTEMACE 1661 #define CFG_SYSTEMACE_BASE 0xf0000000 1662 1663 When SystemACE support is added, the "ace" device type 1664 becomes available to the fat commands, i.e. fatls. 1665 1666- TFTP Fixed UDP Port: 1667 CONFIG_TFTP_PORT 1668 1669 If this is defined, the environment variable tftpsrcp 1670 is used to supply the TFTP UDP source port value. 1671 If tftpsrcp isn't defined, the normal pseudo-random port 1672 number generator is used. 1673 1674 Also, the environment variable tftpdstp is used to supply 1675 the TFTP UDP destination port value. If tftpdstp isn't 1676 defined, the normal port 69 is used. 1677 1678 The purpose for tftpsrcp is to allow a TFTP server to 1679 blindly start the TFTP transfer using the pre-configured 1680 target IP address and UDP port. This has the effect of 1681 "punching through" the (Windows XP) firewall, allowing 1682 the remainder of the TFTP transfer to proceed normally. 1683 A better solution is to properly configure the firewall, 1684 but sometimes that is not allowed. 1685 1686- Show boot progress: 1687 CONFIG_SHOW_BOOT_PROGRESS 1688 1689 Defining this option allows to add some board- 1690 specific code (calling a user-provided function 1691 "show_boot_progress(int)") that enables you to show 1692 the system's boot progress on some display (for 1693 example, some LED's) on your board. At the moment, 1694 the following checkpoints are implemented: 1695 1696Legacy uImage format: 1697 1698 Arg Where When 1699 1 common/cmd_bootm.c before attempting to boot an image 1700 -1 common/cmd_bootm.c Image header has bad magic number 1701 2 common/cmd_bootm.c Image header has correct magic number 1702 -2 common/cmd_bootm.c Image header has bad checksum 1703 3 common/cmd_bootm.c Image header has correct checksum 1704 -3 common/cmd_bootm.c Image data has bad checksum 1705 4 common/cmd_bootm.c Image data has correct checksum 1706 -4 common/cmd_bootm.c Image is for unsupported architecture 1707 5 common/cmd_bootm.c Architecture check OK 1708 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 1709 6 common/cmd_bootm.c Image Type check OK 1710 -6 common/cmd_bootm.c gunzip uncompression error 1711 -7 common/cmd_bootm.c Unimplemented compression type 1712 7 common/cmd_bootm.c Uncompression OK 1713 8 common/cmd_bootm.c No uncompress/copy overwrite error 1714 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1715 1716 9 common/image.c Start initial ramdisk verification 1717 -10 common/image.c Ramdisk header has bad magic number 1718 -11 common/image.c Ramdisk header has bad checksum 1719 10 common/image.c Ramdisk header is OK 1720 -12 common/image.c Ramdisk data has bad checksum 1721 11 common/image.c Ramdisk data has correct checksum 1722 12 common/image.c Ramdisk verification complete, start loading 1723 -13 common/image.c Wrong Image Type (not PPC Linux Ramdisk) 1724 13 common/image.c Start multifile image verification 1725 14 common/image.c No initial ramdisk, no multifile, continue. 1726 1727 15 lib_<arch>/bootm.c All preparation done, transferring control to OS 1728 1729 -30 lib_ppc/board.c Fatal error, hang the system 1730 -31 post/post.c POST test failed, detected by post_output_backlog() 1731 -32 post/post.c POST test failed, detected by post_run_single() 1732 1733 34 common/cmd_doc.c before loading a Image from a DOC device 1734 -35 common/cmd_doc.c Bad usage of "doc" command 1735 35 common/cmd_doc.c correct usage of "doc" command 1736 -36 common/cmd_doc.c No boot device 1737 36 common/cmd_doc.c correct boot device 1738 -37 common/cmd_doc.c Unknown Chip ID on boot device 1739 37 common/cmd_doc.c correct chip ID found, device available 1740 -38 common/cmd_doc.c Read Error on boot device 1741 38 common/cmd_doc.c reading Image header from DOC device OK 1742 -39 common/cmd_doc.c Image header has bad magic number 1743 39 common/cmd_doc.c Image header has correct magic number 1744 -40 common/cmd_doc.c Error reading Image from DOC device 1745 40 common/cmd_doc.c Image header has correct magic number 1746 41 common/cmd_ide.c before loading a Image from a IDE device 1747 -42 common/cmd_ide.c Bad usage of "ide" command 1748 42 common/cmd_ide.c correct usage of "ide" command 1749 -43 common/cmd_ide.c No boot device 1750 43 common/cmd_ide.c boot device found 1751 -44 common/cmd_ide.c Device not available 1752 44 common/cmd_ide.c Device available 1753 -45 common/cmd_ide.c wrong partition selected 1754 45 common/cmd_ide.c partition selected 1755 -46 common/cmd_ide.c Unknown partition table 1756 46 common/cmd_ide.c valid partition table found 1757 -47 common/cmd_ide.c Invalid partition type 1758 47 common/cmd_ide.c correct partition type 1759 -48 common/cmd_ide.c Error reading Image Header on boot device 1760 48 common/cmd_ide.c reading Image Header from IDE device OK 1761 -49 common/cmd_ide.c Image header has bad magic number 1762 49 common/cmd_ide.c Image header has correct magic number 1763 -50 common/cmd_ide.c Image header has bad checksum 1764 50 common/cmd_ide.c Image header has correct checksum 1765 -51 common/cmd_ide.c Error reading Image from IDE device 1766 51 common/cmd_ide.c reading Image from IDE device OK 1767 52 common/cmd_nand.c before loading a Image from a NAND device 1768 -53 common/cmd_nand.c Bad usage of "nand" command 1769 53 common/cmd_nand.c correct usage of "nand" command 1770 -54 common/cmd_nand.c No boot device 1771 54 common/cmd_nand.c boot device found 1772 -55 common/cmd_nand.c Unknown Chip ID on boot device 1773 55 common/cmd_nand.c correct chip ID found, device available 1774 -56 common/cmd_nand.c Error reading Image Header on boot device 1775 56 common/cmd_nand.c reading Image Header from NAND device OK 1776 -57 common/cmd_nand.c Image header has bad magic number 1777 57 common/cmd_nand.c Image header has correct magic number 1778 -58 common/cmd_nand.c Error reading Image from NAND device 1779 58 common/cmd_nand.c reading Image from NAND device OK 1780 1781 -60 common/env_common.c Environment has a bad CRC, using default 1782 1783 64 net/eth.c starting with Ethernetconfiguration. 1784 -64 net/eth.c no Ethernet found. 1785 65 net/eth.c Ethernet found. 1786 1787 -80 common/cmd_net.c usage wrong 1788 80 common/cmd_net.c before calling NetLoop() 1789 -81 common/cmd_net.c some error in NetLoop() occured 1790 81 common/cmd_net.c NetLoop() back without error 1791 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1792 82 common/cmd_net.c trying automatic boot 1793 83 common/cmd_net.c running autoscript 1794 -83 common/cmd_net.c some error in automatic boot or autoscript 1795 84 common/cmd_net.c end without errors 1796 1797FIT uImage format: 1798 1799 Arg Where When 1800 100 common/cmd_bootm.c Kernel FIT Image has correct format 1801 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 1802 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 1803 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 1804 102 common/cmd_bootm.c Kernel unit name specified 1805 -103 common/cmd_bootm.c Can't get kernel subimage node offset 1806 103 common/cmd_bootm.c Found configuration node 1807 104 common/cmd_bootm.c Got kernel subimage node offset 1808 -104 common/cmd_bootm.c Kernel subimage hash verification failed 1809 105 common/cmd_bootm.c Kernel subimage hash verification OK 1810 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 1811 106 common/cmd_bootm.c Architecture check OK 1812 -106 common/cmd_bootm.c Kernel subimage has wrong typea 1813 107 common/cmd_bootm.c Kernel subimge type OK 1814 -107 common/cmd_bootm.c Can't get kernel subimage data/size 1815 108 common/cmd_bootm.c Got kernel subimage data/size 1816 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 1817 -109 common/cmd_bootm.c Can't get kernel subimage type 1818 -110 common/cmd_bootm.c Can't get kernel subimage comp 1819 -111 common/cmd_bootm.c Can't get kernel subimage os 1820 -112 common/cmd_bootm.c Can't get kernel subimage load address 1821 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 1822 1823 120 common/image.c Start initial ramdisk verification 1824 -120 common/image.c Ramdisk FIT image has incorrect format 1825 121 common/image.c Ramdisk FIT image has correct format 1826 122 common/image.c No Ramdisk subimage unit name, using configuration 1827 -122 common/image.c Can't get configuration for ramdisk subimage 1828 123 common/image.c Ramdisk unit name specified 1829 -124 common/image.c Can't get ramdisk subimage node offset 1830 125 common/image.c Got ramdisk subimage node offset 1831 -125 common/image.c Ramdisk subimage hash verification failed 1832 126 common/image.c Ramdisk subimage hash verification OK 1833 -126 common/image.c Ramdisk subimage for unsupported architecture 1834 127 common/image.c Architecture check OK 1835 -127 common/image.c Can't get ramdisk subimage data/size 1836 128 common/image.c Got ramdisk subimage data/size 1837 129 common/image.c Can't get ramdisk load address 1838 -129 common/image.c Got ramdisk load address 1839 1840 -130 common/cmd_doc.c Icorrect FIT image format 1841 131 common/cmd_doc.c FIT image format OK 1842 1843 -140 common/cmd_ide.c Icorrect FIT image format 1844 141 common/cmd_ide.c FIT image format OK 1845 1846 -150 common/cmd_nand.c Icorrect FIT image format 1847 151 common/cmd_nand.c FIT image format OK 1848 1849 1850Modem Support: 1851-------------- 1852 1853[so far only for SMDK2400 and TRAB boards] 1854 1855- Modem support endable: 1856 CONFIG_MODEM_SUPPORT 1857 1858- RTS/CTS Flow control enable: 1859 CONFIG_HWFLOW 1860 1861- Modem debug support: 1862 CONFIG_MODEM_SUPPORT_DEBUG 1863 1864 Enables debugging stuff (char screen[1024], dbg()) 1865 for modem support. Useful only with BDI2000. 1866 1867- Interrupt support (PPC): 1868 1869 There are common interrupt_init() and timer_interrupt() 1870 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1871 for cpu specific initialization. interrupt_init_cpu() 1872 should set decrementer_count to appropriate value. If 1873 cpu resets decrementer automatically after interrupt 1874 (ppc4xx) it should set decrementer_count to zero. 1875 timer_interrupt() calls timer_interrupt_cpu() for cpu 1876 specific handling. If board has watchdog / status_led 1877 / other_activity_monitor it works automatically from 1878 general timer_interrupt(). 1879 1880- General: 1881 1882 In the target system modem support is enabled when a 1883 specific key (key combination) is pressed during 1884 power-on. Otherwise U-Boot will boot normally 1885 (autoboot). The key_pressed() fuction is called from 1886 board_init(). Currently key_pressed() is a dummy 1887 function, returning 1 and thus enabling modem 1888 initialization. 1889 1890 If there are no modem init strings in the 1891 environment, U-Boot proceed to autoboot; the 1892 previous output (banner, info printfs) will be 1893 supressed, though. 1894 1895 See also: doc/README.Modem 1896 1897 1898Configuration Settings: 1899----------------------- 1900 1901- CFG_LONGHELP: Defined when you want long help messages included; 1902 undefine this when you're short of memory. 1903 1904- CFG_PROMPT: This is what U-Boot prints on the console to 1905 prompt for user input. 1906 1907- CFG_CBSIZE: Buffer size for input from the Console 1908 1909- CFG_PBSIZE: Buffer size for Console output 1910 1911- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1912 1913- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1914 the application (usually a Linux kernel) when it is 1915 booted 1916 1917- CFG_BAUDRATE_TABLE: 1918 List of legal baudrate settings for this board. 1919 1920- CFG_CONSOLE_INFO_QUIET 1921 Suppress display of console information at boot. 1922 1923- CFG_CONSOLE_IS_IN_ENV 1924 If the board specific function 1925 extern int overwrite_console (void); 1926 returns 1, the stdin, stderr and stdout are switched to the 1927 serial port, else the settings in the environment are used. 1928 1929- CFG_CONSOLE_OVERWRITE_ROUTINE 1930 Enable the call to overwrite_console(). 1931 1932- CFG_CONSOLE_ENV_OVERWRITE 1933 Enable overwrite of previous console environment settings. 1934 1935- CFG_MEMTEST_START, CFG_MEMTEST_END: 1936 Begin and End addresses of the area used by the 1937 simple memory test. 1938 1939- CFG_ALT_MEMTEST: 1940 Enable an alternate, more extensive memory test. 1941 1942- CFG_MEMTEST_SCRATCH: 1943 Scratch address used by the alternate memory test 1944 You only need to set this if address zero isn't writeable 1945 1946- CFG_TFTP_LOADADDR: 1947 Default load address for network file downloads 1948 1949- CFG_LOADS_BAUD_CHANGE: 1950 Enable temporary baudrate change while serial download 1951 1952- CFG_SDRAM_BASE: 1953 Physical start address of SDRAM. _Must_ be 0 here. 1954 1955- CFG_MBIO_BASE: 1956 Physical start address of Motherboard I/O (if using a 1957 Cogent motherboard) 1958 1959- CFG_FLASH_BASE: 1960 Physical start address of Flash memory. 1961 1962- CFG_MONITOR_BASE: 1963 Physical start address of boot monitor code (set by 1964 make config files to be same as the text base address 1965 (TEXT_BASE) used when linking) - same as 1966 CFG_FLASH_BASE when booting from flash. 1967 1968- CFG_MONITOR_LEN: 1969 Size of memory reserved for monitor code, used to 1970 determine _at_compile_time_ (!) if the environment is 1971 embedded within the U-Boot image, or in a separate 1972 flash sector. 1973 1974- CFG_MALLOC_LEN: 1975 Size of DRAM reserved for malloc() use. 1976 1977- CFG_BOOTM_LEN: 1978 Normally compressed uImages are limited to an 1979 uncompressed size of 8 MBytes. If this is not enough, 1980 you can define CFG_BOOTM_LEN in your board config file 1981 to adjust this setting to your needs. 1982 1983- CFG_BOOTMAPSZ: 1984 Maximum size of memory mapped by the startup code of 1985 the Linux kernel; all data that must be processed by 1986 the Linux kernel (bd_info, boot arguments, eventually 1987 initrd image) must be put below this limit. 1988 1989- CFG_MAX_FLASH_BANKS: 1990 Max number of Flash memory banks 1991 1992- CFG_MAX_FLASH_SECT: 1993 Max number of sectors on a Flash chip 1994 1995- CFG_FLASH_ERASE_TOUT: 1996 Timeout for Flash erase operations (in ms) 1997 1998- CFG_FLASH_WRITE_TOUT: 1999 Timeout for Flash write operations (in ms) 2000 2001- CFG_FLASH_LOCK_TOUT 2002 Timeout for Flash set sector lock bit operation (in ms) 2003 2004- CFG_FLASH_UNLOCK_TOUT 2005 Timeout for Flash clear lock bits operation (in ms) 2006 2007- CFG_FLASH_PROTECTION 2008 If defined, hardware flash sectors protection is used 2009 instead of U-Boot software protection. 2010 2011- CFG_DIRECT_FLASH_TFTP: 2012 2013 Enable TFTP transfers directly to flash memory; 2014 without this option such a download has to be 2015 performed in two steps: (1) download to RAM, and (2) 2016 copy from RAM to flash. 2017 2018 The two-step approach is usually more reliable, since 2019 you can check if the download worked before you erase 2020 the flash, but in some situations (when sytem RAM is 2021 too limited to allow for a tempory copy of the 2022 downloaded image) this option may be very useful. 2023 2024- CFG_FLASH_CFI: 2025 Define if the flash driver uses extra elements in the 2026 common flash structure for storing flash geometry. 2027 2028- CFG_FLASH_CFI_DRIVER 2029 This option also enables the building of the cfi_flash driver 2030 in the drivers directory 2031 2032- CFG_FLASH_QUIET_TEST 2033 If this option is defined, the common CFI flash doesn't 2034 print it's warning upon not recognized FLASH banks. This 2035 is useful, if some of the configured banks are only 2036 optionally available. 2037 2038- CONFIG_FLASH_SHOW_PROGRESS 2039 If defined (must be an integer), print out countdown 2040 digits and dots. Recommended value: 45 (9..1) for 80 2041 column displays, 15 (3..1) for 40 column displays. 2042 2043- CFG_RX_ETH_BUFFER: 2044 Defines the number of ethernet receive buffers. On some 2045 ethernet controllers it is recommended to set this value 2046 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2047 buffers can be full shortly after enabling the interface 2048 on high ethernet traffic. 2049 Defaults to 4 if not defined. 2050 2051The following definitions that deal with the placement and management 2052of environment data (variable area); in general, we support the 2053following configurations: 2054 2055- CFG_ENV_IS_IN_FLASH: 2056 2057 Define this if the environment is in flash memory. 2058 2059 a) The environment occupies one whole flash sector, which is 2060 "embedded" in the text segment with the U-Boot code. This 2061 happens usually with "bottom boot sector" or "top boot 2062 sector" type flash chips, which have several smaller 2063 sectors at the start or the end. For instance, such a 2064 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2065 such a case you would place the environment in one of the 2066 4 kB sectors - with U-Boot code before and after it. With 2067 "top boot sector" type flash chips, you would put the 2068 environment in one of the last sectors, leaving a gap 2069 between U-Boot and the environment. 2070 2071 - CFG_ENV_OFFSET: 2072 2073 Offset of environment data (variable area) to the 2074 beginning of flash memory; for instance, with bottom boot 2075 type flash chips the second sector can be used: the offset 2076 for this sector is given here. 2077 2078 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2079 2080 - CFG_ENV_ADDR: 2081 2082 This is just another way to specify the start address of 2083 the flash sector containing the environment (instead of 2084 CFG_ENV_OFFSET). 2085 2086 - CFG_ENV_SECT_SIZE: 2087 2088 Size of the sector containing the environment. 2089 2090 2091 b) Sometimes flash chips have few, equal sized, BIG sectors. 2092 In such a case you don't want to spend a whole sector for 2093 the environment. 2094 2095 - CFG_ENV_SIZE: 2096 2097 If you use this in combination with CFG_ENV_IS_IN_FLASH 2098 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2099 of this flash sector for the environment. This saves 2100 memory for the RAM copy of the environment. 2101 2102 It may also save flash memory if you decide to use this 2103 when your environment is "embedded" within U-Boot code, 2104 since then the remainder of the flash sector could be used 2105 for U-Boot code. It should be pointed out that this is 2106 STRONGLY DISCOURAGED from a robustness point of view: 2107 updating the environment in flash makes it always 2108 necessary to erase the WHOLE sector. If something goes 2109 wrong before the contents has been restored from a copy in 2110 RAM, your target system will be dead. 2111 2112 - CFG_ENV_ADDR_REDUND 2113 CFG_ENV_SIZE_REDUND 2114 2115 These settings describe a second storage area used to hold 2116 a redundand copy of the environment data, so that there is 2117 a valid backup copy in case there is a power failure during 2118 a "saveenv" operation. 2119 2120BE CAREFUL! Any changes to the flash layout, and some changes to the 2121source code will make it necessary to adapt <board>/u-boot.lds* 2122accordingly! 2123 2124 2125- CFG_ENV_IS_IN_NVRAM: 2126 2127 Define this if you have some non-volatile memory device 2128 (NVRAM, battery buffered SRAM) which you want to use for the 2129 environment. 2130 2131 - CFG_ENV_ADDR: 2132 - CFG_ENV_SIZE: 2133 2134 These two #defines are used to determin the memory area you 2135 want to use for environment. It is assumed that this memory 2136 can just be read and written to, without any special 2137 provision. 2138 2139BE CAREFUL! The first access to the environment happens quite early 2140in U-Boot initalization (when we try to get the setting of for the 2141console baudrate). You *MUST* have mappend your NVRAM area then, or 2142U-Boot will hang. 2143 2144Please note that even with NVRAM we still use a copy of the 2145environment in RAM: we could work on NVRAM directly, but we want to 2146keep settings there always unmodified except somebody uses "saveenv" 2147to save the current settings. 2148 2149 2150- CFG_ENV_IS_IN_EEPROM: 2151 2152 Use this if you have an EEPROM or similar serial access 2153 device and a driver for it. 2154 2155 - CFG_ENV_OFFSET: 2156 - CFG_ENV_SIZE: 2157 2158 These two #defines specify the offset and size of the 2159 environment area within the total memory of your EEPROM. 2160 2161 - CFG_I2C_EEPROM_ADDR: 2162 If defined, specified the chip address of the EEPROM device. 2163 The default address is zero. 2164 2165 - CFG_EEPROM_PAGE_WRITE_BITS: 2166 If defined, the number of bits used to address bytes in a 2167 single page in the EEPROM device. A 64 byte page, for example 2168 would require six bits. 2169 2170 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2171 If defined, the number of milliseconds to delay between 2172 page writes. The default is zero milliseconds. 2173 2174 - CFG_I2C_EEPROM_ADDR_LEN: 2175 The length in bytes of the EEPROM memory array address. Note 2176 that this is NOT the chip address length! 2177 2178 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2179 EEPROM chips that implement "address overflow" are ones 2180 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2181 address and the extra bits end up in the "chip address" bit 2182 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2183 byte chips. 2184 2185 Note that we consider the length of the address field to 2186 still be one byte because the extra address bits are hidden 2187 in the chip address. 2188 2189 - CFG_EEPROM_SIZE: 2190 The size in bytes of the EEPROM device. 2191 2192 2193- CFG_ENV_IS_IN_DATAFLASH: 2194 2195 Define this if you have a DataFlash memory device which you 2196 want to use for the environment. 2197 2198 - CFG_ENV_OFFSET: 2199 - CFG_ENV_ADDR: 2200 - CFG_ENV_SIZE: 2201 2202 These three #defines specify the offset and size of the 2203 environment area within the total memory of your DataFlash placed 2204 at the specified address. 2205 2206- CFG_ENV_IS_IN_NAND: 2207 2208 Define this if you have a NAND device which you want to use 2209 for the environment. 2210 2211 - CFG_ENV_OFFSET: 2212 - CFG_ENV_SIZE: 2213 2214 These two #defines specify the offset and size of the environment 2215 area within the first NAND device. 2216 2217 - CFG_ENV_OFFSET_REDUND 2218 2219 This setting describes a second storage area of CFG_ENV_SIZE 2220 size used to hold a redundant copy of the environment data, 2221 so that there is a valid backup copy in case there is a 2222 power failure during a "saveenv" operation. 2223 2224 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2225 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2226 the NAND devices block size. 2227 2228- CFG_SPI_INIT_OFFSET 2229 2230 Defines offset to the initial SPI buffer area in DPRAM. The 2231 area is used at an early stage (ROM part) if the environment 2232 is configured to reside in the SPI EEPROM: We need a 520 byte 2233 scratch DPRAM area. It is used between the two initialization 2234 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2235 to be a good choice since it makes it far enough from the 2236 start of the data area as well as from the stack pointer. 2237 2238Please note that the environment is read-only until the monitor 2239has been relocated to RAM and a RAM copy of the environment has been 2240created; also, when using EEPROM you will have to use getenv_r() 2241until then to read environment variables. 2242 2243The environment is protected by a CRC32 checksum. Before the monitor 2244is relocated into RAM, as a result of a bad CRC you will be working 2245with the compiled-in default environment - *silently*!!! [This is 2246necessary, because the first environment variable we need is the 2247"baudrate" setting for the console - if we have a bad CRC, we don't 2248have any device yet where we could complain.] 2249 2250Note: once the monitor has been relocated, then it will complain if 2251the default environment is used; a new CRC is computed as soon as you 2252use the "saveenv" command to store a valid environment. 2253 2254- CFG_FAULT_ECHO_LINK_DOWN: 2255 Echo the inverted Ethernet link state to the fault LED. 2256 2257 Note: If this option is active, then CFG_FAULT_MII_ADDR 2258 also needs to be defined. 2259 2260- CFG_FAULT_MII_ADDR: 2261 MII address of the PHY to check for the Ethernet link state. 2262 2263- CFG_64BIT_VSPRINTF: 2264 Makes vsprintf (and all *printf functions) support printing 2265 of 64bit values by using the L quantifier 2266 2267- CFG_64BIT_STRTOUL: 2268 Adds simple_strtoull that returns a 64bit value 2269 2270Low Level (hardware related) configuration options: 2271--------------------------------------------------- 2272 2273- CFG_CACHELINE_SIZE: 2274 Cache Line Size of the CPU. 2275 2276- CFG_DEFAULT_IMMR: 2277 Default address of the IMMR after system reset. 2278 2279 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2280 and RPXsuper) to be able to adjust the position of 2281 the IMMR register after a reset. 2282 2283- Floppy Disk Support: 2284 CFG_FDC_DRIVE_NUMBER 2285 2286 the default drive number (default value 0) 2287 2288 CFG_ISA_IO_STRIDE 2289 2290 defines the spacing between fdc chipset registers 2291 (default value 1) 2292 2293 CFG_ISA_IO_OFFSET 2294 2295 defines the offset of register from address. It 2296 depends on which part of the data bus is connected to 2297 the fdc chipset. (default value 0) 2298 2299 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2300 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2301 default value. 2302 2303 if CFG_FDC_HW_INIT is defined, then the function 2304 fdc_hw_init() is called at the beginning of the FDC 2305 setup. fdc_hw_init() must be provided by the board 2306 source code. It is used to make hardware dependant 2307 initializations. 2308 2309- CFG_IMMR: Physical address of the Internal Memory. 2310 DO NOT CHANGE unless you know exactly what you're 2311 doing! (11-4) [MPC8xx/82xx systems only] 2312 2313- CFG_INIT_RAM_ADDR: 2314 2315 Start address of memory area that can be used for 2316 initial data and stack; please note that this must be 2317 writable memory that is working WITHOUT special 2318 initialization, i. e. you CANNOT use normal RAM which 2319 will become available only after programming the 2320 memory controller and running certain initialization 2321 sequences. 2322 2323 U-Boot uses the following memory types: 2324 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2325 - MPC824X: data cache 2326 - PPC4xx: data cache 2327 2328- CFG_GBL_DATA_OFFSET: 2329 2330 Offset of the initial data structure in the memory 2331 area defined by CFG_INIT_RAM_ADDR. Usually 2332 CFG_GBL_DATA_OFFSET is chosen such that the initial 2333 data is located at the end of the available space 2334 (sometimes written as (CFG_INIT_RAM_END - 2335 CFG_INIT_DATA_SIZE), and the initial stack is just 2336 below that area (growing from (CFG_INIT_RAM_ADDR + 2337 CFG_GBL_DATA_OFFSET) downward. 2338 2339 Note: 2340 On the MPC824X (or other systems that use the data 2341 cache for initial memory) the address chosen for 2342 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2343 point to an otherwise UNUSED address space between 2344 the top of RAM and the start of the PCI space. 2345 2346- CFG_SIUMCR: SIU Module Configuration (11-6) 2347 2348- CFG_SYPCR: System Protection Control (11-9) 2349 2350- CFG_TBSCR: Time Base Status and Control (11-26) 2351 2352- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2353 2354- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2355 2356- CFG_SCCR: System Clock and reset Control Register (15-27) 2357 2358- CFG_OR_TIMING_SDRAM: 2359 SDRAM timing 2360 2361- CFG_MAMR_PTA: 2362 periodic timer for refresh 2363 2364- CFG_DER: Debug Event Register (37-47) 2365 2366- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2367 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2368 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2369 CFG_BR1_PRELIM: 2370 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2371 2372- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2373 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2374 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2375 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2376 2377- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2378 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2379 Machine Mode Register and Memory Periodic Timer 2380 Prescaler definitions (SDRAM timing) 2381 2382- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2383 enable I2C microcode relocation patch (MPC8xx); 2384 define relocation offset in DPRAM [DSP2] 2385 2386- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2387 enable SMC microcode relocation patch (MPC8xx); 2388 define relocation offset in DPRAM [SMC1] 2389 2390- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2391 enable SPI microcode relocation patch (MPC8xx); 2392 define relocation offset in DPRAM [SCC4] 2393 2394- CFG_USE_OSCCLK: 2395 Use OSCM clock mode on MBX8xx board. Be careful, 2396 wrong setting might damage your board. Read 2397 doc/README.MBX before setting this variable! 2398 2399- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2400 Offset of the bootmode word in DPRAM used by post 2401 (Power On Self Tests). This definition overrides 2402 #define'd default value in commproc.h resp. 2403 cpm_8260.h. 2404 2405- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2406 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2407 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2408 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2409 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2410 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2411 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2412 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2413 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2414 2415- CONFIG_SPD_EEPROM 2416 Get DDR timing information from an I2C EEPROM. Common 2417 with pluggable memory modules such as SODIMMs 2418 2419 SPD_EEPROM_ADDRESS 2420 I2C address of the SPD EEPROM 2421 2422- CFG_SPD_BUS_NUM 2423 If SPD EEPROM is on an I2C bus other than the first 2424 one, specify here. Note that the value must resolve 2425 to something your driver can deal with. 2426 2427- CFG_83XX_DDR_USES_CS0 2428 Only for 83xx systems. If specified, then DDR should 2429 be configured using CS0 and CS1 instead of CS2 and CS3. 2430 2431- CFG_83XX_DDR_USES_CS0 2432 Only for 83xx systems. If specified, then DDR should 2433 be configured using CS0 and CS1 instead of CS2 and CS3. 2434 2435- CONFIG_ETHER_ON_FEC[12] 2436 Define to enable FEC[12] on a 8xx series processor. 2437 2438- CONFIG_FEC[12]_PHY 2439 Define to the hardcoded PHY address which corresponds 2440 to the given FEC; i. e. 2441 #define CONFIG_FEC1_PHY 4 2442 means that the PHY with address 4 is connected to FEC1 2443 2444 When set to -1, means to probe for first available. 2445 2446- CONFIG_FEC[12]_PHY_NORXERR 2447 The PHY does not have a RXERR line (RMII only). 2448 (so program the FEC to ignore it). 2449 2450- CONFIG_RMII 2451 Enable RMII mode for all FECs. 2452 Note that this is a global option, we can't 2453 have one FEC in standard MII mode and another in RMII mode. 2454 2455- CONFIG_CRC32_VERIFY 2456 Add a verify option to the crc32 command. 2457 The syntax is: 2458 2459 => crc32 -v <address> <count> <crc32> 2460 2461 Where address/count indicate a memory area 2462 and crc32 is the correct crc32 which the 2463 area should have. 2464 2465- CONFIG_LOOPW 2466 Add the "loopw" memory command. This only takes effect if 2467 the memory commands are activated globally (CONFIG_CMD_MEM). 2468 2469- CONFIG_MX_CYCLIC 2470 Add the "mdc" and "mwc" memory commands. These are cyclic 2471 "md/mw" commands. 2472 Examples: 2473 2474 => mdc.b 10 4 500 2475 This command will print 4 bytes (10,11,12,13) each 500 ms. 2476 2477 => mwc.l 100 12345678 10 2478 This command will write 12345678 to address 100 all 10 ms. 2479 2480 This only takes effect if the memory commands are activated 2481 globally (CONFIG_CMD_MEM). 2482 2483- CONFIG_SKIP_LOWLEVEL_INIT 2484- CONFIG_SKIP_RELOCATE_UBOOT 2485 2486 [ARM only] If these variables are defined, then 2487 certain low level initializations (like setting up 2488 the memory controller) are omitted and/or U-Boot does 2489 not relocate itself into RAM. 2490 Normally these variables MUST NOT be defined. The 2491 only exception is when U-Boot is loaded (to RAM) by 2492 some other boot loader or by a debugger which 2493 performs these intializations itself. 2494 2495 2496Building the Software: 2497====================== 2498 2499Building U-Boot has been tested in several native build environments 2500and in many different cross environments. Of course we cannot support 2501all possibly existing versions of cross development tools in all 2502(potentially obsolete) versions. In case of tool chain problems we 2503recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2504which is extensively used to build and test U-Boot. 2505 2506If you are not using a native environment, it is assumed that you 2507have GNU cross compiling tools available in your path. In this case, 2508you must set the environment variable CROSS_COMPILE in your shell. 2509Note that no changes to the Makefile or any other source files are 2510necessary. For example using the ELDK on a 4xx CPU, please enter: 2511 2512 $ CROSS_COMPILE=ppc_4xx- 2513 $ export CROSS_COMPILE 2514 2515U-Boot is intended to be simple to build. After installing the 2516sources you must configure U-Boot for one specific board type. This 2517is done by typing: 2518 2519 make NAME_config 2520 2521where "NAME_config" is the name of one of the existing configu- 2522rations; see the main Makefile for supported names. 2523 2524Note: for some board special configuration names may exist; check if 2525 additional information is available from the board vendor; for 2526 instance, the TQM823L systems are available without (standard) 2527 or with LCD support. You can select such additional "features" 2528 when chosing the configuration, i. e. 2529 2530 make TQM823L_config 2531 - will configure for a plain TQM823L, i. e. no LCD support 2532 2533 make TQM823L_LCD_config 2534 - will configure for a TQM823L with U-Boot console on LCD 2535 2536 etc. 2537 2538 2539Finally, type "make all", and you should get some working U-Boot 2540images ready for download to / installation on your system: 2541 2542- "u-boot.bin" is a raw binary image 2543- "u-boot" is an image in ELF binary format 2544- "u-boot.srec" is in Motorola S-Record format 2545 2546By default the build is performed locally and the objects are saved 2547in the source directory. One of the two methods can be used to change 2548this behavior and build U-Boot to some external directory: 2549 25501. Add O= to the make command line invocations: 2551 2552 make O=/tmp/build distclean 2553 make O=/tmp/build NAME_config 2554 make O=/tmp/build all 2555 25562. Set environment variable BUILD_DIR to point to the desired location: 2557 2558 export BUILD_DIR=/tmp/build 2559 make distclean 2560 make NAME_config 2561 make all 2562 2563Note that the command line "O=" setting overrides the BUILD_DIR environment 2564variable. 2565 2566 2567Please be aware that the Makefiles assume you are using GNU make, so 2568for instance on NetBSD you might need to use "gmake" instead of 2569native "make". 2570 2571 2572If the system board that you have is not listed, then you will need 2573to port U-Boot to your hardware platform. To do this, follow these 2574steps: 2575 25761. Add a new configuration option for your board to the toplevel 2577 "Makefile" and to the "MAKEALL" script, using the existing 2578 entries as examples. Note that here and at many other places 2579 boards and other names are listed in alphabetical sort order. Please 2580 keep this order. 25812. Create a new directory to hold your board specific code. Add any 2582 files you need. In your board directory, you will need at least 2583 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 25843. Create a new configuration file "include/configs/<board>.h" for 2585 your board 25863. If you're porting U-Boot to a new CPU, then also create a new 2587 directory to hold your CPU specific code. Add any files you need. 25884. Run "make <board>_config" with your new name. 25895. Type "make", and you should get a working "u-boot.srec" file 2590 to be installed on your target system. 25916. Debug and solve any problems that might arise. 2592 [Of course, this last step is much harder than it sounds.] 2593 2594 2595Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2596============================================================== 2597 2598If you have modified U-Boot sources (for instance added a new board 2599or support for new devices, a new CPU, etc.) you are expected to 2600provide feedback to the other developers. The feedback normally takes 2601the form of a "patch", i. e. a context diff against a certain (latest 2602official or latest in the git repository) version of U-Boot sources. 2603 2604But before you submit such a patch, please verify that your modifi- 2605cation did not break existing code. At least make sure that *ALL* of 2606the supported boards compile WITHOUT ANY compiler warnings. To do so, 2607just run the "MAKEALL" script, which will configure and build U-Boot 2608for ALL supported system. Be warned, this will take a while. You can 2609select which (cross) compiler to use by passing a `CROSS_COMPILE' 2610environment variable to the script, i. e. to use the ELDK cross tools 2611you can type 2612 2613 CROSS_COMPILE=ppc_8xx- MAKEALL 2614 2615or to build on a native PowerPC system you can type 2616 2617 CROSS_COMPILE=' ' MAKEALL 2618 2619When using the MAKEALL script, the default behaviour is to build 2620U-Boot in the source directory. This location can be changed by 2621setting the BUILD_DIR environment variable. Also, for each target 2622built, the MAKEALL script saves two log files (<target>.ERR and 2623<target>.MAKEALL) in the <source dir>/LOG directory. This default 2624location can be changed by setting the MAKEALL_LOGDIR environment 2625variable. For example: 2626 2627 export BUILD_DIR=/tmp/build 2628 export MAKEALL_LOGDIR=/tmp/log 2629 CROSS_COMPILE=ppc_8xx- MAKEALL 2630 2631With the above settings build objects are saved in the /tmp/build, 2632log files are saved in the /tmp/log and the source tree remains clean 2633during the whole build process. 2634 2635 2636See also "U-Boot Porting Guide" below. 2637 2638 2639Monitor Commands - Overview: 2640============================ 2641 2642go - start application at address 'addr' 2643run - run commands in an environment variable 2644bootm - boot application image from memory 2645bootp - boot image via network using BootP/TFTP protocol 2646tftpboot- boot image via network using TFTP protocol 2647 and env variables "ipaddr" and "serverip" 2648 (and eventually "gatewayip") 2649rarpboot- boot image via network using RARP/TFTP protocol 2650diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2651loads - load S-Record file over serial line 2652loadb - load binary file over serial line (kermit mode) 2653md - memory display 2654mm - memory modify (auto-incrementing) 2655nm - memory modify (constant address) 2656mw - memory write (fill) 2657cp - memory copy 2658cmp - memory compare 2659crc32 - checksum calculation 2660imd - i2c memory display 2661imm - i2c memory modify (auto-incrementing) 2662inm - i2c memory modify (constant address) 2663imw - i2c memory write (fill) 2664icrc32 - i2c checksum calculation 2665iprobe - probe to discover valid I2C chip addresses 2666iloop - infinite loop on address range 2667isdram - print SDRAM configuration information 2668sspi - SPI utility commands 2669base - print or set address offset 2670printenv- print environment variables 2671setenv - set environment variables 2672saveenv - save environment variables to persistent storage 2673protect - enable or disable FLASH write protection 2674erase - erase FLASH memory 2675flinfo - print FLASH memory information 2676bdinfo - print Board Info structure 2677iminfo - print header information for application image 2678coninfo - print console devices and informations 2679ide - IDE sub-system 2680loop - infinite loop on address range 2681loopw - infinite write loop on address range 2682mtest - simple RAM test 2683icache - enable or disable instruction cache 2684dcache - enable or disable data cache 2685reset - Perform RESET of the CPU 2686echo - echo args to console 2687version - print monitor version 2688help - print online help 2689? - alias for 'help' 2690 2691 2692Monitor Commands - Detailed Description: 2693======================================== 2694 2695TODO. 2696 2697For now: just type "help <command>". 2698 2699 2700Environment Variables: 2701====================== 2702 2703U-Boot supports user configuration using Environment Variables which 2704can be made persistent by saving to Flash memory. 2705 2706Environment Variables are set using "setenv", printed using 2707"printenv", and saved to Flash using "saveenv". Using "setenv" 2708without a value can be used to delete a variable from the 2709environment. As long as you don't save the environment you are 2710working with an in-memory copy. In case the Flash area containing the 2711environment is erased by accident, a default environment is provided. 2712 2713Some configuration options can be set using Environment Variables: 2714 2715 baudrate - see CONFIG_BAUDRATE 2716 2717 bootdelay - see CONFIG_BOOTDELAY 2718 2719 bootcmd - see CONFIG_BOOTCOMMAND 2720 2721 bootargs - Boot arguments when booting an RTOS image 2722 2723 bootfile - Name of the image to load with TFTP 2724 2725 autoload - if set to "no" (any string beginning with 'n'), 2726 "bootp" will just load perform a lookup of the 2727 configuration from the BOOTP server, but not try to 2728 load any image using TFTP 2729 2730 autoscript - if set to "yes" commands like "loadb", "loady", 2731 "bootp", "tftpb", "rarpboot" and "nfs" will attempt 2732 to automatically run script images (by internally 2733 calling "autoscript"). 2734 2735 autoscript_uname - if script image is in a format (FIT) this 2736 variable is used to get script subimage unit name. 2737 2738 autostart - if set to "yes", an image loaded using the "bootp", 2739 "rarpboot", "tftpboot" or "diskboot" commands will 2740 be automatically started (by internally calling 2741 "bootm") 2742 2743 If set to "no", a standalone image passed to the 2744 "bootm" command will be copied to the load address 2745 (and eventually uncompressed), but NOT be started. 2746 This can be used to load and uncompress arbitrary 2747 data. 2748 2749 i2cfast - (PPC405GP|PPC405EP only) 2750 if set to 'y' configures Linux I2C driver for fast 2751 mode (400kHZ). This environment variable is used in 2752 initialization code. So, for changes to be effective 2753 it must be saved and board must be reset. 2754 2755 initrd_high - restrict positioning of initrd images: 2756 If this variable is not set, initrd images will be 2757 copied to the highest possible address in RAM; this 2758 is usually what you want since it allows for 2759 maximum initrd size. If for some reason you want to 2760 make sure that the initrd image is loaded below the 2761 CFG_BOOTMAPSZ limit, you can set this environment 2762 variable to a value of "no" or "off" or "0". 2763 Alternatively, you can set it to a maximum upper 2764 address to use (U-Boot will still check that it 2765 does not overwrite the U-Boot stack and data). 2766 2767 For instance, when you have a system with 16 MB 2768 RAM, and want to reserve 4 MB from use by Linux, 2769 you can do this by adding "mem=12M" to the value of 2770 the "bootargs" variable. However, now you must make 2771 sure that the initrd image is placed in the first 2772 12 MB as well - this can be done with 2773 2774 setenv initrd_high 00c00000 2775 2776 If you set initrd_high to 0xFFFFFFFF, this is an 2777 indication to U-Boot that all addresses are legal 2778 for the Linux kernel, including addresses in flash 2779 memory. In this case U-Boot will NOT COPY the 2780 ramdisk at all. This may be useful to reduce the 2781 boot time on your system, but requires that this 2782 feature is supported by your Linux kernel. 2783 2784 ipaddr - IP address; needed for tftpboot command 2785 2786 loadaddr - Default load address for commands like "bootp", 2787 "rarpboot", "tftpboot", "loadb" or "diskboot" 2788 2789 loads_echo - see CONFIG_LOADS_ECHO 2790 2791 serverip - TFTP server IP address; needed for tftpboot command 2792 2793 bootretry - see CONFIG_BOOT_RETRY_TIME 2794 2795 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2796 2797 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2798 2799 ethprime - When CONFIG_NET_MULTI is enabled controls which 2800 interface is used first. 2801 2802 ethact - When CONFIG_NET_MULTI is enabled controls which 2803 interface is currently active. For example you 2804 can do the following 2805 2806 => setenv ethact FEC ETHERNET 2807 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2808 => setenv ethact SCC ETHERNET 2809 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2810 2811 ethrotate - When set to "no" U-Boot does not go through all 2812 available network interfaces. 2813 It just stays at the currently selected interface. 2814 2815 netretry - When set to "no" each network operation will 2816 either succeed or fail without retrying. 2817 When set to "once" the network operation will 2818 fail when all the available network interfaces 2819 are tried once without success. 2820 Useful on scripts which control the retry operation 2821 themselves. 2822 2823 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2824 if set load address for the npe microcode 2825 2826 tftpsrcport - If this is set, the value is used for TFTP's 2827 UDP source port. 2828 2829 tftpdstport - If this is set, the value is used for TFTP's UDP 2830 destination port instead of the Well Know Port 69. 2831 2832 vlan - When set to a value < 4095 the traffic over 2833 ethernet is encapsulated/received over 802.1q 2834 VLAN tagged frames. 2835 2836The following environment variables may be used and automatically 2837updated by the network boot commands ("bootp" and "rarpboot"), 2838depending the information provided by your boot server: 2839 2840 bootfile - see above 2841 dnsip - IP address of your Domain Name Server 2842 dnsip2 - IP address of your secondary Domain Name Server 2843 gatewayip - IP address of the Gateway (Router) to use 2844 hostname - Target hostname 2845 ipaddr - see above 2846 netmask - Subnet Mask 2847 rootpath - Pathname of the root filesystem on the NFS server 2848 serverip - see above 2849 2850 2851There are two special Environment Variables: 2852 2853 serial# - contains hardware identification information such 2854 as type string and/or serial number 2855 ethaddr - Ethernet address 2856 2857These variables can be set only once (usually during manufacturing of 2858the board). U-Boot refuses to delete or overwrite these variables 2859once they have been set once. 2860 2861 2862Further special Environment Variables: 2863 2864 ver - Contains the U-Boot version string as printed 2865 with the "version" command. This variable is 2866 readonly (see CONFIG_VERSION_VARIABLE). 2867 2868 2869Please note that changes to some configuration parameters may take 2870only effect after the next boot (yes, that's just like Windoze :-). 2871 2872 2873Command Line Parsing: 2874===================== 2875 2876There are two different command line parsers available with U-Boot: 2877the old "simple" one, and the much more powerful "hush" shell: 2878 2879Old, simple command line parser: 2880-------------------------------- 2881 2882- supports environment variables (through setenv / saveenv commands) 2883- several commands on one line, separated by ';' 2884- variable substitution using "... ${name} ..." syntax 2885- special characters ('$', ';') can be escaped by prefixing with '\', 2886 for example: 2887 setenv bootcmd bootm \${address} 2888- You can also escape text by enclosing in single apostrophes, for example: 2889 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2890 2891Hush shell: 2892----------- 2893 2894- similar to Bourne shell, with control structures like 2895 if...then...else...fi, for...do...done; while...do...done, 2896 until...do...done, ... 2897- supports environment ("global") variables (through setenv / saveenv 2898 commands) and local shell variables (through standard shell syntax 2899 "name=value"); only environment variables can be used with "run" 2900 command 2901 2902General rules: 2903-------------- 2904 2905(1) If a command line (or an environment variable executed by a "run" 2906 command) contains several commands separated by semicolon, and 2907 one of these commands fails, then the remaining commands will be 2908 executed anyway. 2909 2910(2) If you execute several variables with one call to run (i. e. 2911 calling run with a list af variables as arguments), any failing 2912 command will cause "run" to terminate, i. e. the remaining 2913 variables are not executed. 2914 2915Note for Redundant Ethernet Interfaces: 2916======================================= 2917 2918Some boards come with redundant ethernet interfaces; U-Boot supports 2919such configurations and is capable of automatic selection of a 2920"working" interface when needed. MAC assignment works as follows: 2921 2922Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2923MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2924"eth1addr" (=>eth1), "eth2addr", ... 2925 2926If the network interface stores some valid MAC address (for instance 2927in SROM), this is used as default address if there is NO correspon- 2928ding setting in the environment; if the corresponding environment 2929variable is set, this overrides the settings in the card; that means: 2930 2931o If the SROM has a valid MAC address, and there is no address in the 2932 environment, the SROM's address is used. 2933 2934o If there is no valid address in the SROM, and a definition in the 2935 environment exists, then the value from the environment variable is 2936 used. 2937 2938o If both the SROM and the environment contain a MAC address, and 2939 both addresses are the same, this MAC address is used. 2940 2941o If both the SROM and the environment contain a MAC address, and the 2942 addresses differ, the value from the environment is used and a 2943 warning is printed. 2944 2945o If neither SROM nor the environment contain a MAC address, an error 2946 is raised. 2947 2948 2949Image Formats: 2950============== 2951 2952U-Boot is capable of booting (and performing other auxiliary operations on) 2953images in two formats: 2954 2955New uImage format (FIT) 2956----------------------- 2957 2958Flexible and powerful format based on Flattened Image Tree -- FIT (similar 2959to Flattened Device Tree). It allows the use of images with multiple 2960components (several kernels, ramdisks, etc.), with contents protected by 2961SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 2962 2963 2964Old uImage format 2965----------------- 2966 2967Old image format is based on binary files which can be basically anything, 2968preceded by a special header; see the definitions in include/image.h for 2969details; basically, the header defines the following image properties: 2970 2971* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2972 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2973 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2974 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2975* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 2976 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2977 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 2978* Compression Type (uncompressed, gzip, bzip2) 2979* Load Address 2980* Entry Point 2981* Image Name 2982* Image Timestamp 2983 2984The header is marked by a special Magic Number, and both the header 2985and the data portions of the image are secured against corruption by 2986CRC32 checksums. 2987 2988 2989Linux Support: 2990============== 2991 2992Although U-Boot should support any OS or standalone application 2993easily, the main focus has always been on Linux during the design of 2994U-Boot. 2995 2996U-Boot includes many features that so far have been part of some 2997special "boot loader" code within the Linux kernel. Also, any 2998"initrd" images to be used are no longer part of one big Linux image; 2999instead, kernel and "initrd" are separate images. This implementation 3000serves several purposes: 3001 3002- the same features can be used for other OS or standalone 3003 applications (for instance: using compressed images to reduce the 3004 Flash memory footprint) 3005 3006- it becomes much easier to port new Linux kernel versions because 3007 lots of low-level, hardware dependent stuff are done by U-Boot 3008 3009- the same Linux kernel image can now be used with different "initrd" 3010 images; of course this also means that different kernel images can 3011 be run with the same "initrd". This makes testing easier (you don't 3012 have to build a new "zImage.initrd" Linux image when you just 3013 change a file in your "initrd"). Also, a field-upgrade of the 3014 software is easier now. 3015 3016 3017Linux HOWTO: 3018============ 3019 3020Porting Linux to U-Boot based systems: 3021--------------------------------------- 3022 3023U-Boot cannot save you from doing all the necessary modifications to 3024configure the Linux device drivers for use with your target hardware 3025(no, we don't intend to provide a full virtual machine interface to 3026Linux :-). 3027 3028But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 3029 3030Just make sure your machine specific header file (for instance 3031include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3032Information structure as we define in include/u-boot.h, and make 3033sure that your definition of IMAP_ADDR uses the same value as your 3034U-Boot configuration in CFG_IMMR. 3035 3036 3037Configuring the Linux kernel: 3038----------------------------- 3039 3040No specific requirements for U-Boot. Make sure you have some root 3041device (initial ramdisk, NFS) for your target system. 3042 3043 3044Building a Linux Image: 3045----------------------- 3046 3047With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3048not used. If you use recent kernel source, a new build target 3049"uImage" will exist which automatically builds an image usable by 3050U-Boot. Most older kernels also have support for a "pImage" target, 3051which was introduced for our predecessor project PPCBoot and uses a 3052100% compatible format. 3053 3054Example: 3055 3056 make TQM850L_config 3057 make oldconfig 3058 make dep 3059 make uImage 3060 3061The "uImage" build target uses a special tool (in 'tools/mkimage') to 3062encapsulate a compressed Linux kernel image with header information, 3063CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3064 3065* build a standard "vmlinux" kernel image (in ELF binary format): 3066 3067* convert the kernel into a raw binary image: 3068 3069 ${CROSS_COMPILE}-objcopy -O binary \ 3070 -R .note -R .comment \ 3071 -S vmlinux linux.bin 3072 3073* compress the binary image: 3074 3075 gzip -9 linux.bin 3076 3077* package compressed binary image for U-Boot: 3078 3079 mkimage -A ppc -O linux -T kernel -C gzip \ 3080 -a 0 -e 0 -n "Linux Kernel Image" \ 3081 -d linux.bin.gz uImage 3082 3083 3084The "mkimage" tool can also be used to create ramdisk images for use 3085with U-Boot, either separated from the Linux kernel image, or 3086combined into one file. "mkimage" encapsulates the images with a 64 3087byte header containing information about target architecture, 3088operating system, image type, compression method, entry points, time 3089stamp, CRC32 checksums, etc. 3090 3091"mkimage" can be called in two ways: to verify existing images and 3092print the header information, or to build new images. 3093 3094In the first form (with "-l" option) mkimage lists the information 3095contained in the header of an existing U-Boot image; this includes 3096checksum verification: 3097 3098 tools/mkimage -l image 3099 -l ==> list image header information 3100 3101The second form (with "-d" option) is used to build a U-Boot image 3102from a "data file" which is used as image payload: 3103 3104 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3105 -n name -d data_file image 3106 -A ==> set architecture to 'arch' 3107 -O ==> set operating system to 'os' 3108 -T ==> set image type to 'type' 3109 -C ==> set compression type 'comp' 3110 -a ==> set load address to 'addr' (hex) 3111 -e ==> set entry point to 'ep' (hex) 3112 -n ==> set image name to 'name' 3113 -d ==> use image data from 'datafile' 3114 3115Right now, all Linux kernels for PowerPC systems use the same load 3116address (0x00000000), but the entry point address depends on the 3117kernel version: 3118 3119- 2.2.x kernels have the entry point at 0x0000000C, 3120- 2.3.x and later kernels have the entry point at 0x00000000. 3121 3122So a typical call to build a U-Boot image would read: 3123 3124 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3125 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3126 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3127 > examples/uImage.TQM850L 3128 Image Name: 2.4.4 kernel for TQM850L 3129 Created: Wed Jul 19 02:34:59 2000 3130 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3131 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3132 Load Address: 0x00000000 3133 Entry Point: 0x00000000 3134 3135To verify the contents of the image (or check for corruption): 3136 3137 -> tools/mkimage -l examples/uImage.TQM850L 3138 Image Name: 2.4.4 kernel for TQM850L 3139 Created: Wed Jul 19 02:34:59 2000 3140 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3141 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3142 Load Address: 0x00000000 3143 Entry Point: 0x00000000 3144 3145NOTE: for embedded systems where boot time is critical you can trade 3146speed for memory and install an UNCOMPRESSED image instead: this 3147needs more space in Flash, but boots much faster since it does not 3148need to be uncompressed: 3149 3150 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3151 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3152 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3153 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3154 > examples/uImage.TQM850L-uncompressed 3155 Image Name: 2.4.4 kernel for TQM850L 3156 Created: Wed Jul 19 02:34:59 2000 3157 Image Type: PowerPC Linux Kernel Image (uncompressed) 3158 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3159 Load Address: 0x00000000 3160 Entry Point: 0x00000000 3161 3162 3163Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3164when your kernel is intended to use an initial ramdisk: 3165 3166 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3167 > -A ppc -O linux -T ramdisk -C gzip \ 3168 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3169 Image Name: Simple Ramdisk Image 3170 Created: Wed Jan 12 14:01:50 2000 3171 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3172 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3173 Load Address: 0x00000000 3174 Entry Point: 0x00000000 3175 3176 3177Installing a Linux Image: 3178------------------------- 3179 3180To downloading a U-Boot image over the serial (console) interface, 3181you must convert the image to S-Record format: 3182 3183 objcopy -I binary -O srec examples/image examples/image.srec 3184 3185The 'objcopy' does not understand the information in the U-Boot 3186image header, so the resulting S-Record file will be relative to 3187address 0x00000000. To load it to a given address, you need to 3188specify the target address as 'offset' parameter with the 'loads' 3189command. 3190 3191Example: install the image to address 0x40100000 (which on the 3192TQM8xxL is in the first Flash bank): 3193 3194 => erase 40100000 401FFFFF 3195 3196 .......... done 3197 Erased 8 sectors 3198 3199 => loads 40100000 3200 ## Ready for S-Record download ... 3201 ~>examples/image.srec 3202 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3203 ... 3204 15989 15990 15991 15992 3205 [file transfer complete] 3206 [connected] 3207 ## Start Addr = 0x00000000 3208 3209 3210You can check the success of the download using the 'iminfo' command; 3211this includes a checksum verification so you can be sure no data 3212corruption happened: 3213 3214 => imi 40100000 3215 3216 ## Checking Image at 40100000 ... 3217 Image Name: 2.2.13 for initrd on TQM850L 3218 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3219 Data Size: 335725 Bytes = 327 kB = 0 MB 3220 Load Address: 00000000 3221 Entry Point: 0000000c 3222 Verifying Checksum ... OK 3223 3224 3225Boot Linux: 3226----------- 3227 3228The "bootm" command is used to boot an application that is stored in 3229memory (RAM or Flash). In case of a Linux kernel image, the contents 3230of the "bootargs" environment variable is passed to the kernel as 3231parameters. You can check and modify this variable using the 3232"printenv" and "setenv" commands: 3233 3234 3235 => printenv bootargs 3236 bootargs=root=/dev/ram 3237 3238 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3239 3240 => printenv bootargs 3241 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3242 3243 => bootm 40020000 3244 ## Booting Linux kernel at 40020000 ... 3245 Image Name: 2.2.13 for NFS on TQM850L 3246 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3247 Data Size: 381681 Bytes = 372 kB = 0 MB 3248 Load Address: 00000000 3249 Entry Point: 0000000c 3250 Verifying Checksum ... OK 3251 Uncompressing Kernel Image ... OK 3252 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 3253 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3254 time_init: decrementer frequency = 187500000/60 3255 Calibrating delay loop... 49.77 BogoMIPS 3256 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3257 ... 3258 3259If you want to boot a Linux kernel with initial ram disk, you pass 3260the memory addresses of both the kernel and the initrd image (PPBCOOT 3261format!) to the "bootm" command: 3262 3263 => imi 40100000 40200000 3264 3265 ## Checking Image at 40100000 ... 3266 Image Name: 2.2.13 for initrd on TQM850L 3267 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3268 Data Size: 335725 Bytes = 327 kB = 0 MB 3269 Load Address: 00000000 3270 Entry Point: 0000000c 3271 Verifying Checksum ... OK 3272 3273 ## Checking Image at 40200000 ... 3274 Image Name: Simple Ramdisk Image 3275 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3276 Data Size: 566530 Bytes = 553 kB = 0 MB 3277 Load Address: 00000000 3278 Entry Point: 00000000 3279 Verifying Checksum ... OK 3280 3281 => bootm 40100000 40200000 3282 ## Booting Linux kernel at 40100000 ... 3283 Image Name: 2.2.13 for initrd on TQM850L 3284 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3285 Data Size: 335725 Bytes = 327 kB = 0 MB 3286 Load Address: 00000000 3287 Entry Point: 0000000c 3288 Verifying Checksum ... OK 3289 Uncompressing Kernel Image ... OK 3290 ## Loading RAMDisk Image at 40200000 ... 3291 Image Name: Simple Ramdisk Image 3292 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3293 Data Size: 566530 Bytes = 553 kB = 0 MB 3294 Load Address: 00000000 3295 Entry Point: 00000000 3296 Verifying Checksum ... OK 3297 Loading Ramdisk ... OK 3298 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 3299 Boot arguments: root=/dev/ram 3300 time_init: decrementer frequency = 187500000/60 3301 Calibrating delay loop... 49.77 BogoMIPS 3302 ... 3303 RAMDISK: Compressed image found at block 0 3304 VFS: Mounted root (ext2 filesystem). 3305 3306 bash# 3307 3308Boot Linux and pass a flat device tree: 3309----------- 3310 3311First, U-Boot must be compiled with the appropriate defines. See the section 3312titled "Linux Kernel Interface" above for a more in depth explanation. The 3313following is an example of how to start a kernel and pass an updated 3314flat device tree: 3315 3316=> print oftaddr 3317oftaddr=0x300000 3318=> print oft 3319oft=oftrees/mpc8540ads.dtb 3320=> tftp $oftaddr $oft 3321Speed: 1000, full duplex 3322Using TSEC0 device 3323TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3324Filename 'oftrees/mpc8540ads.dtb'. 3325Load address: 0x300000 3326Loading: # 3327done 3328Bytes transferred = 4106 (100a hex) 3329=> tftp $loadaddr $bootfile 3330Speed: 1000, full duplex 3331Using TSEC0 device 3332TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3333Filename 'uImage'. 3334Load address: 0x200000 3335Loading:############ 3336done 3337Bytes transferred = 1029407 (fb51f hex) 3338=> print loadaddr 3339loadaddr=200000 3340=> print oftaddr 3341oftaddr=0x300000 3342=> bootm $loadaddr - $oftaddr 3343## Booting image at 00200000 ... 3344 Image Name: Linux-2.6.17-dirty 3345 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3346 Data Size: 1029343 Bytes = 1005.2 kB 3347 Load Address: 00000000 3348 Entry Point: 00000000 3349 Verifying Checksum ... OK 3350 Uncompressing Kernel Image ... OK 3351Booting using flat device tree at 0x300000 3352Using MPC85xx ADS machine description 3353Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3354[snip] 3355 3356 3357More About U-Boot Image Types: 3358------------------------------ 3359 3360U-Boot supports the following image types: 3361 3362 "Standalone Programs" are directly runnable in the environment 3363 provided by U-Boot; it is expected that (if they behave 3364 well) you can continue to work in U-Boot after return from 3365 the Standalone Program. 3366 "OS Kernel Images" are usually images of some Embedded OS which 3367 will take over control completely. Usually these programs 3368 will install their own set of exception handlers, device 3369 drivers, set up the MMU, etc. - this means, that you cannot 3370 expect to re-enter U-Boot except by resetting the CPU. 3371 "RAMDisk Images" are more or less just data blocks, and their 3372 parameters (address, size) are passed to an OS kernel that is 3373 being started. 3374 "Multi-File Images" contain several images, typically an OS 3375 (Linux) kernel image and one or more data images like 3376 RAMDisks. This construct is useful for instance when you want 3377 to boot over the network using BOOTP etc., where the boot 3378 server provides just a single image file, but you want to get 3379 for instance an OS kernel and a RAMDisk image. 3380 3381 "Multi-File Images" start with a list of image sizes, each 3382 image size (in bytes) specified by an "uint32_t" in network 3383 byte order. This list is terminated by an "(uint32_t)0". 3384 Immediately after the terminating 0 follow the images, one by 3385 one, all aligned on "uint32_t" boundaries (size rounded up to 3386 a multiple of 4 bytes). 3387 3388 "Firmware Images" are binary images containing firmware (like 3389 U-Boot or FPGA images) which usually will be programmed to 3390 flash memory. 3391 3392 "Script files" are command sequences that will be executed by 3393 U-Boot's command interpreter; this feature is especially 3394 useful when you configure U-Boot to use a real shell (hush) 3395 as command interpreter. 3396 3397 3398Standalone HOWTO: 3399================= 3400 3401One of the features of U-Boot is that you can dynamically load and 3402run "standalone" applications, which can use some resources of 3403U-Boot like console I/O functions or interrupt services. 3404 3405Two simple examples are included with the sources: 3406 3407"Hello World" Demo: 3408------------------- 3409 3410'examples/hello_world.c' contains a small "Hello World" Demo 3411application; it is automatically compiled when you build U-Boot. 3412It's configured to run at address 0x00040004, so you can play with it 3413like that: 3414 3415 => loads 3416 ## Ready for S-Record download ... 3417 ~>examples/hello_world.srec 3418 1 2 3 4 5 6 7 8 9 10 11 ... 3419 [file transfer complete] 3420 [connected] 3421 ## Start Addr = 0x00040004 3422 3423 => go 40004 Hello World! This is a test. 3424 ## Starting application at 0x00040004 ... 3425 Hello World 3426 argc = 7 3427 argv[0] = "40004" 3428 argv[1] = "Hello" 3429 argv[2] = "World!" 3430 argv[3] = "This" 3431 argv[4] = "is" 3432 argv[5] = "a" 3433 argv[6] = "test." 3434 argv[7] = "<NULL>" 3435 Hit any key to exit ... 3436 3437 ## Application terminated, rc = 0x0 3438 3439Another example, which demonstrates how to register a CPM interrupt 3440handler with the U-Boot code, can be found in 'examples/timer.c'. 3441Here, a CPM timer is set up to generate an interrupt every second. 3442The interrupt service routine is trivial, just printing a '.' 3443character, but this is just a demo program. The application can be 3444controlled by the following keys: 3445 3446 ? - print current values og the CPM Timer registers 3447 b - enable interrupts and start timer 3448 e - stop timer and disable interrupts 3449 q - quit application 3450 3451 => loads 3452 ## Ready for S-Record download ... 3453 ~>examples/timer.srec 3454 1 2 3 4 5 6 7 8 9 10 11 ... 3455 [file transfer complete] 3456 [connected] 3457 ## Start Addr = 0x00040004 3458 3459 => go 40004 3460 ## Starting application at 0x00040004 ... 3461 TIMERS=0xfff00980 3462 Using timer 1 3463 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3464 3465Hit 'b': 3466 [q, b, e, ?] Set interval 1000000 us 3467 Enabling timer 3468Hit '?': 3469 [q, b, e, ?] ........ 3470 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3471Hit '?': 3472 [q, b, e, ?] . 3473 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3474Hit '?': 3475 [q, b, e, ?] . 3476 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3477Hit '?': 3478 [q, b, e, ?] . 3479 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3480Hit 'e': 3481 [q, b, e, ?] ...Stopping timer 3482Hit 'q': 3483 [q, b, e, ?] ## Application terminated, rc = 0x0 3484 3485 3486Minicom warning: 3487================ 3488 3489Over time, many people have reported problems when trying to use the 3490"minicom" terminal emulation program for serial download. I (wd) 3491consider minicom to be broken, and recommend not to use it. Under 3492Unix, I recommend to use C-Kermit for general purpose use (and 3493especially for kermit binary protocol download ("loadb" command), and 3494use "cu" for S-Record download ("loads" command). 3495 3496Nevertheless, if you absolutely want to use it try adding this 3497configuration to your "File transfer protocols" section: 3498 3499 Name Program Name U/D FullScr IO-Red. Multi 3500 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3501 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3502 3503 3504NetBSD Notes: 3505============= 3506 3507Starting at version 0.9.2, U-Boot supports NetBSD both as host 3508(build U-Boot) and target system (boots NetBSD/mpc8xx). 3509 3510Building requires a cross environment; it is known to work on 3511NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3512need gmake since the Makefiles are not compatible with BSD make). 3513Note that the cross-powerpc package does not install include files; 3514attempting to build U-Boot will fail because <machine/ansi.h> is 3515missing. This file has to be installed and patched manually: 3516 3517 # cd /usr/pkg/cross/powerpc-netbsd/include 3518 # mkdir powerpc 3519 # ln -s powerpc machine 3520 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3521 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3522 3523Native builds *don't* work due to incompatibilities between native 3524and U-Boot include files. 3525 3526Booting assumes that (the first part of) the image booted is a 3527stage-2 loader which in turn loads and then invokes the kernel 3528proper. Loader sources will eventually appear in the NetBSD source 3529tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3530meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3531 3532 3533Implementation Internals: 3534========================= 3535 3536The following is not intended to be a complete description of every 3537implementation detail. However, it should help to understand the 3538inner workings of U-Boot and make it easier to port it to custom 3539hardware. 3540 3541 3542Initial Stack, Global Data: 3543--------------------------- 3544 3545The implementation of U-Boot is complicated by the fact that U-Boot 3546starts running out of ROM (flash memory), usually without access to 3547system RAM (because the memory controller is not initialized yet). 3548This means that we don't have writable Data or BSS segments, and BSS 3549is not initialized as zero. To be able to get a C environment working 3550at all, we have to allocate at least a minimal stack. Implementation 3551options for this are defined and restricted by the CPU used: Some CPU 3552models provide on-chip memory (like the IMMR area on MPC8xx and 3553MPC826x processors), on others (parts of) the data cache can be 3554locked as (mis-) used as memory, etc. 3555 3556 Chris Hallinan posted a good summary of these issues to the 3557 u-boot-users mailing list: 3558 3559 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3560 From: "Chris Hallinan" <clh@net1plus.com> 3561 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3562 ... 3563 3564 Correct me if I'm wrong, folks, but the way I understand it 3565 is this: Using DCACHE as initial RAM for Stack, etc, does not 3566 require any physical RAM backing up the cache. The cleverness 3567 is that the cache is being used as a temporary supply of 3568 necessary storage before the SDRAM controller is setup. It's 3569 beyond the scope of this list to expain the details, but you 3570 can see how this works by studying the cache architecture and 3571 operation in the architecture and processor-specific manuals. 3572 3573 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3574 is another option for the system designer to use as an 3575 initial stack/ram area prior to SDRAM being available. Either 3576 option should work for you. Using CS 4 should be fine if your 3577 board designers haven't used it for something that would 3578 cause you grief during the initial boot! It is frequently not 3579 used. 3580 3581 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3582 with your processor/board/system design. The default value 3583 you will find in any recent u-boot distribution in 3584 walnut.h should work for you. I'd set it to a value larger 3585 than your SDRAM module. If you have a 64MB SDRAM module, set 3586 it above 400_0000. Just make sure your board has no resources 3587 that are supposed to respond to that address! That code in 3588 start.S has been around a while and should work as is when 3589 you get the config right. 3590 3591 -Chris Hallinan 3592 DS4.COM, Inc. 3593 3594It is essential to remember this, since it has some impact on the C 3595code for the initialization procedures: 3596 3597* Initialized global data (data segment) is read-only. Do not attempt 3598 to write it. 3599 3600* Do not use any unitialized global data (or implicitely initialized 3601 as zero data - BSS segment) at all - this is undefined, initiali- 3602 zation is performed later (when relocating to RAM). 3603 3604* Stack space is very limited. Avoid big data buffers or things like 3605 that. 3606 3607Having only the stack as writable memory limits means we cannot use 3608normal global data to share information beween the code. But it 3609turned out that the implementation of U-Boot can be greatly 3610simplified by making a global data structure (gd_t) available to all 3611functions. We could pass a pointer to this data as argument to _all_ 3612functions, but this would bloat the code. Instead we use a feature of 3613the GCC compiler (Global Register Variables) to share the data: we 3614place a pointer (gd) to the global data into a register which we 3615reserve for this purpose. 3616 3617When choosing a register for such a purpose we are restricted by the 3618relevant (E)ABI specifications for the current architecture, and by 3619GCC's implementation. 3620 3621For PowerPC, the following registers have specific use: 3622 R1: stack pointer 3623 R2: reserved for system use 3624 R3-R4: parameter passing and return values 3625 R5-R10: parameter passing 3626 R13: small data area pointer 3627 R30: GOT pointer 3628 R31: frame pointer 3629 3630 (U-Boot also uses R14 as internal GOT pointer.) 3631 3632 ==> U-Boot will use R2 to hold a pointer to the global data 3633 3634 Note: on PPC, we could use a static initializer (since the 3635 address of the global data structure is known at compile time), 3636 but it turned out that reserving a register results in somewhat 3637 smaller code - although the code savings are not that big (on 3638 average for all boards 752 bytes for the whole U-Boot image, 3639 624 text + 127 data). 3640 3641On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3642 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3643 3644 ==> U-Boot will use P5 to hold a pointer to the global data 3645 3646On ARM, the following registers are used: 3647 3648 R0: function argument word/integer result 3649 R1-R3: function argument word 3650 R9: GOT pointer 3651 R10: stack limit (used only if stack checking if enabled) 3652 R11: argument (frame) pointer 3653 R12: temporary workspace 3654 R13: stack pointer 3655 R14: link register 3656 R15: program counter 3657 3658 ==> U-Boot will use R8 to hold a pointer to the global data 3659 3660NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3661or current versions of GCC may "optimize" the code too much. 3662 3663Memory Management: 3664------------------ 3665 3666U-Boot runs in system state and uses physical addresses, i.e. the 3667MMU is not used either for address mapping nor for memory protection. 3668 3669The available memory is mapped to fixed addresses using the memory 3670controller. In this process, a contiguous block is formed for each 3671memory type (Flash, SDRAM, SRAM), even when it consists of several 3672physical memory banks. 3673 3674U-Boot is installed in the first 128 kB of the first Flash bank (on 3675TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3676booting and sizing and initializing DRAM, the code relocates itself 3677to the upper end of DRAM. Immediately below the U-Boot code some 3678memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3679configuration setting]. Below that, a structure with global Board 3680Info data is placed, followed by the stack (growing downward). 3681 3682Additionally, some exception handler code is copied to the low 8 kB 3683of DRAM (0x00000000 ... 0x00001FFF). 3684 3685So a typical memory configuration with 16 MB of DRAM could look like 3686this: 3687 3688 0x0000 0000 Exception Vector code 3689 : 3690 0x0000 1FFF 3691 0x0000 2000 Free for Application Use 3692 : 3693 : 3694 3695 : 3696 : 3697 0x00FB FF20 Monitor Stack (Growing downward) 3698 0x00FB FFAC Board Info Data and permanent copy of global data 3699 0x00FC 0000 Malloc Arena 3700 : 3701 0x00FD FFFF 3702 0x00FE 0000 RAM Copy of Monitor Code 3703 ... eventually: LCD or video framebuffer 3704 ... eventually: pRAM (Protected RAM - unchanged by reset) 3705 0x00FF FFFF [End of RAM] 3706 3707 3708System Initialization: 3709---------------------- 3710 3711In the reset configuration, U-Boot starts at the reset entry point 3712(on most PowerPC systens at address 0x00000100). Because of the reset 3713configuration for CS0# this is a mirror of the onboard Flash memory. 3714To be able to re-map memory U-Boot then jumps to its link address. 3715To be able to implement the initialization code in C, a (small!) 3716initial stack is set up in the internal Dual Ported RAM (in case CPUs 3717which provide such a feature like MPC8xx or MPC8260), or in a locked 3718part of the data cache. After that, U-Boot initializes the CPU core, 3719the caches and the SIU. 3720 3721Next, all (potentially) available memory banks are mapped using a 3722preliminary mapping. For example, we put them on 512 MB boundaries 3723(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3724on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3725programmed for SDRAM access. Using the temporary configuration, a 3726simple memory test is run that determines the size of the SDRAM 3727banks. 3728 3729When there is more than one SDRAM bank, and the banks are of 3730different size, the largest is mapped first. For equal size, the first 3731bank (CS2#) is mapped first. The first mapping is always for address 37320x00000000, with any additional banks following immediately to create 3733contiguous memory starting from 0. 3734 3735Then, the monitor installs itself at the upper end of the SDRAM area 3736and allocates memory for use by malloc() and for the global Board 3737Info data; also, the exception vector code is copied to the low RAM 3738pages, and the final stack is set up. 3739 3740Only after this relocation will you have a "normal" C environment; 3741until that you are restricted in several ways, mostly because you are 3742running from ROM, and because the code will have to be relocated to a 3743new address in RAM. 3744 3745 3746U-Boot Porting Guide: 3747---------------------- 3748 3749[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3750list, October 2002] 3751 3752 3753int main (int argc, char *argv[]) 3754{ 3755 sighandler_t no_more_time; 3756 3757 signal (SIGALRM, no_more_time); 3758 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3759 3760 if (available_money > available_manpower) { 3761 pay consultant to port U-Boot; 3762 return 0; 3763 } 3764 3765 Download latest U-Boot source; 3766 3767 Subscribe to u-boot-users mailing list; 3768 3769 if (clueless) { 3770 email ("Hi, I am new to U-Boot, how do I get started?"); 3771 } 3772 3773 while (learning) { 3774 Read the README file in the top level directory; 3775 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3776 Read the source, Luke; 3777 } 3778 3779 if (available_money > toLocalCurrency ($2500)) { 3780 Buy a BDI2000; 3781 } else { 3782 Add a lot of aggravation and time; 3783 } 3784 3785 Create your own board support subdirectory; 3786 3787 Create your own board config file; 3788 3789 while (!running) { 3790 do { 3791 Add / modify source code; 3792 } until (compiles); 3793 Debug; 3794 if (clueless) 3795 email ("Hi, I am having problems..."); 3796 } 3797 Send patch file to Wolfgang; 3798 3799 return 0; 3800} 3801 3802void no_more_time (int sig) 3803{ 3804 hire_a_guru(); 3805} 3806 3807 3808Coding Standards: 3809----------------- 3810 3811All contributions to U-Boot should conform to the Linux kernel 3812coding style; see the file "Documentation/CodingStyle" and the script 3813"scripts/Lindent" in your Linux kernel source directory. In sources 3814originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3815spaces before parameters to function calls) is actually used. 3816 3817Source files originating from a different project (for example the 3818MTD subsystem) are generally exempt from these guidelines and are not 3819reformated to ease subsequent migration to newer versions of those 3820sources. 3821 3822Please note that U-Boot is implemented in C (and to some small parts in 3823Assembler); no C++ is used, so please do not use C++ style comments (//) 3824in your code. 3825 3826Please also stick to the following formatting rules: 3827- remove any trailing white space 3828- use TAB characters for indentation, not spaces 3829- make sure NOT to use DOS '\r\n' line feeds 3830- do not add more than 2 empty lines to source files 3831- do not add trailing empty lines to source files 3832 3833Submissions which do not conform to the standards may be returned 3834with a request to reformat the changes. 3835 3836 3837Submitting Patches: 3838------------------- 3839 3840Since the number of patches for U-Boot is growing, we need to 3841establish some rules. Submissions which do not conform to these rules 3842may be rejected, even when they contain important and valuable stuff. 3843 3844Patches shall be sent to the u-boot-users mailing list. 3845 3846Please see http://www.denx.de/wiki/UBoot/Patches for details. 3847 3848When you send a patch, please include the following information with 3849it: 3850 3851* For bug fixes: a description of the bug and how your patch fixes 3852 this bug. Please try to include a way of demonstrating that the 3853 patch actually fixes something. 3854 3855* For new features: a description of the feature and your 3856 implementation. 3857 3858* A CHANGELOG entry as plaintext (separate from the patch) 3859 3860* For major contributions, your entry to the CREDITS file 3861 3862* When you add support for a new board, don't forget to add this 3863 board to the MAKEALL script, too. 3864 3865* If your patch adds new configuration options, don't forget to 3866 document these in the README file. 3867 3868* The patch itself. If you are using git (which is *strongly* 3869 recommended) you can easily generate the patch using the 3870 "git-format-patch". If you then use "git-send-email" to send it to 3871 the U-Boot mailing list, you will avoid most of the common problems 3872 with some other mail clients. 3873 3874 If you cannot use git, use "diff -purN OLD NEW". If your version of 3875 diff does not support these options, then get the latest version of 3876 GNU diff. 3877 3878 The current directory when running this command shall be the parent 3879 directory of the U-Boot source tree (i. e. please make sure that 3880 your patch includes sufficient directory information for the 3881 affected files). 3882 3883 We prefer patches as plain text. MIME attachments are discouraged, 3884 and compressed attachments must not be used. 3885 3886* If one logical set of modifications affects or creates several 3887 files, all these changes shall be submitted in a SINGLE patch file. 3888 3889* Changesets that contain different, unrelated modifications shall be 3890 submitted as SEPARATE patches, one patch per changeset. 3891 3892 3893Notes: 3894 3895* Before sending the patch, run the MAKEALL script on your patched 3896 source tree and make sure that no errors or warnings are reported 3897 for any of the boards. 3898 3899* Keep your modifications to the necessary minimum: A patch 3900 containing several unrelated changes or arbitrary reformats will be 3901 returned with a request to re-formatting / split it. 3902 3903* If you modify existing code, make sure that your new code does not 3904 add to the memory footprint of the code ;-) Small is beautiful! 3905 When adding new features, these should compile conditionally only 3906 (using #ifdef), and the resulting code with the new feature 3907 disabled must not need more memory than the old code without your 3908 modification. 3909 3910* Remember that there is a size limit of 40 kB per message on the 3911 u-boot-users mailing list. Bigger patches will be moderated. If 3912 they are reasonable and not bigger than 100 kB, they will be 3913 acknowledged. Even bigger patches should be avoided. 3914