1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /avr32 Files generic to AVR32 architecture 140 /blackfin Files generic to Analog Devices Blackfin architecture 141 /m68k Files generic to m68k architecture 142 /microblaze Files generic to microblaze architecture 143 /mips Files generic to MIPS architecture 144 /nds32 Files generic to NDS32 architecture 145 /nios2 Files generic to Altera NIOS2 architecture 146 /openrisc Files generic to OpenRISC architecture 147 /powerpc Files generic to PowerPC architecture 148 /sandbox Files generic to HW-independent "sandbox" 149 /sh Files generic to SH architecture 150 /sparc Files generic to SPARC architecture 151 /x86 Files generic to x86 architecture 152/api Machine/arch independent API for external apps 153/board Board dependent files 154/common Misc architecture independent functions 155/configs Board default configuration files 156/disk Code for disk drive partition handling 157/doc Documentation (don't expect too much) 158/drivers Commonly used device drivers 159/dts Contains Makefile for building internal U-Boot fdt. 160/examples Example code for standalone applications, etc. 161/fs Filesystem code (cramfs, ext2, jffs2, etc.) 162/include Header Files 163/lib Library routines generic to all architectures 164/Licenses Various license files 165/net Networking code 166/post Power On Self Test 167/scripts Various build scripts and Makefiles 168/test Various unit test files 169/tools Tools to build S-Record or U-Boot images, etc. 170 171Software Configuration: 172======================= 173 174Configuration is usually done using C preprocessor defines; the 175rationale behind that is to avoid dead code whenever possible. 176 177There are two classes of configuration variables: 178 179* Configuration _OPTIONS_: 180 These are selectable by the user and have names beginning with 181 "CONFIG_". 182 183* Configuration _SETTINGS_: 184 These depend on the hardware etc. and should not be meddled with if 185 you don't know what you're doing; they have names beginning with 186 "CONFIG_SYS_". 187 188Previously, all configuration was done by hand, which involved creating 189symbolic links and editing configuration files manually. More recently, 190U-Boot has added the Kbuild infrastructure used by the Linux kernel, 191allowing you to use the "make menuconfig" command to configure your 192build. 193 194 195Selection of Processor Architecture and Board Type: 196--------------------------------------------------- 197 198For all supported boards there are ready-to-use default 199configurations available; just type "make <board_name>_defconfig". 200 201Example: For a TQM823L module type: 202 203 cd u-boot 204 make TQM823L_defconfig 205 206Note: If you're looking for the default configuration file for a board 207you're sure used to be there but is now missing, check the file 208doc/README.scrapyard for a list of no longer supported boards. 209 210Sandbox Environment: 211-------------------- 212 213U-Boot can be built natively to run on a Linux host using the 'sandbox' 214board. This allows feature development which is not board- or architecture- 215specific to be undertaken on a native platform. The sandbox is also used to 216run some of U-Boot's tests. 217 218See board/sandbox/README.sandbox for more details. 219 220 221Board Initialisation Flow: 222-------------------------- 223 224This is the intended start-up flow for boards. This should apply for both 225SPL and U-Boot proper (i.e. they both follow the same rules). 226 227Note: "SPL" stands for "Secondary Program Loader," which is explained in 228more detail later in this file. 229 230At present, SPL mostly uses a separate code path, but the function names 231and roles of each function are the same. Some boards or architectures 232may not conform to this. At least most ARM boards which use 233CONFIG_SPL_FRAMEWORK conform to this. 234 235Execution typically starts with an architecture-specific (and possibly 236CPU-specific) start.S file, such as: 237 238 - arch/arm/cpu/armv7/start.S 239 - arch/powerpc/cpu/mpc83xx/start.S 240 - arch/mips/cpu/start.S 241 242and so on. From there, three functions are called; the purpose and 243limitations of each of these functions are described below. 244 245lowlevel_init(): 246 - purpose: essential init to permit execution to reach board_init_f() 247 - no global_data or BSS 248 - there is no stack (ARMv7 may have one but it will soon be removed) 249 - must not set up SDRAM or use console 250 - must only do the bare minimum to allow execution to continue to 251 board_init_f() 252 - this is almost never needed 253 - return normally from this function 254 255board_init_f(): 256 - purpose: set up the machine ready for running board_init_r(): 257 i.e. SDRAM and serial UART 258 - global_data is available 259 - stack is in SRAM 260 - BSS is not available, so you cannot use global/static variables, 261 only stack variables and global_data 262 263 Non-SPL-specific notes: 264 - dram_init() is called to set up DRAM. If already done in SPL this 265 can do nothing 266 267 SPL-specific notes: 268 - you can override the entire board_init_f() function with your own 269 version as needed. 270 - preloader_console_init() can be called here in extremis 271 - should set up SDRAM, and anything needed to make the UART work 272 - these is no need to clear BSS, it will be done by crt0.S 273 - must return normally from this function (don't call board_init_r() 274 directly) 275 276Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 277this point the stack and global_data are relocated to below 278CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 279memory. 280 281board_init_r(): 282 - purpose: main execution, common code 283 - global_data is available 284 - SDRAM is available 285 - BSS is available, all static/global variables can be used 286 - execution eventually continues to main_loop() 287 288 Non-SPL-specific notes: 289 - U-Boot is relocated to the top of memory and is now running from 290 there. 291 292 SPL-specific notes: 293 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 294 CONFIG_SPL_STACK_R_ADDR points into SDRAM 295 - preloader_console_init() can be called here - typically this is 296 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 297 spl_board_init() function containing this call 298 - loads U-Boot or (in falcon mode) Linux 299 300 301 302Configuration Options: 303---------------------- 304 305Configuration depends on the combination of board and CPU type; all 306such information is kept in a configuration file 307"include/configs/<board_name>.h". 308 309Example: For a TQM823L module, all configuration settings are in 310"include/configs/TQM823L.h". 311 312 313Many of the options are named exactly as the corresponding Linux 314kernel configuration options. The intention is to make it easier to 315build a config tool - later. 316 317 318The following options need to be configured: 319 320- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 321 322- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 323 324- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 325 Define exactly one, e.g. CONFIG_ATSTK1002 326 327- CPU Module Type: (if CONFIG_COGENT is defined) 328 Define exactly one of 329 CONFIG_CMA286_60_OLD 330--- FIXME --- not tested yet: 331 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 332 CONFIG_CMA287_23, CONFIG_CMA287_50 333 334- Motherboard Type: (if CONFIG_COGENT is defined) 335 Define exactly one of 336 CONFIG_CMA101, CONFIG_CMA102 337 338- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 339 Define one or more of 340 CONFIG_CMA302 341 342- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 343 Define one or more of 344 CONFIG_LCD_HEARTBEAT - update a character position on 345 the LCD display every second with 346 a "rotator" |\-/|\-/ 347 348- Marvell Family Member 349 CONFIG_SYS_MVFS - define it if you want to enable 350 multiple fs option at one time 351 for marvell soc family 352 353- 8xx CPU Options: (if using an MPC8xx CPU) 354 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 355 get_gclk_freq() cannot work 356 e.g. if there is no 32KHz 357 reference PIT/RTC clock 358 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 359 or XTAL/EXTAL) 360 361- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 362 CONFIG_SYS_8xx_CPUCLK_MIN 363 CONFIG_SYS_8xx_CPUCLK_MAX 364 CONFIG_8xx_CPUCLK_DEFAULT 365 See doc/README.MPC866 366 367 CONFIG_SYS_MEASURE_CPUCLK 368 369 Define this to measure the actual CPU clock instead 370 of relying on the correctness of the configured 371 values. Mostly useful for board bringup to make sure 372 the PLL is locked at the intended frequency. Note 373 that this requires a (stable) reference clock (32 kHz 374 RTC clock or CONFIG_SYS_8XX_XIN) 375 376 CONFIG_SYS_DELAYED_ICACHE 377 378 Define this option if you want to enable the 379 ICache only when Code runs from RAM. 380 381- 85xx CPU Options: 382 CONFIG_SYS_PPC64 383 384 Specifies that the core is a 64-bit PowerPC implementation (implements 385 the "64" category of the Power ISA). This is necessary for ePAPR 386 compliance, among other possible reasons. 387 388 CONFIG_SYS_FSL_TBCLK_DIV 389 390 Defines the core time base clock divider ratio compared to the 391 system clock. On most PQ3 devices this is 8, on newer QorIQ 392 devices it can be 16 or 32. The ratio varies from SoC to Soc. 393 394 CONFIG_SYS_FSL_PCIE_COMPAT 395 396 Defines the string to utilize when trying to match PCIe device 397 tree nodes for the given platform. 398 399 CONFIG_SYS_PPC_E500_DEBUG_TLB 400 401 Enables a temporary TLB entry to be used during boot to work 402 around limitations in e500v1 and e500v2 external debugger 403 support. This reduces the portions of the boot code where 404 breakpoints and single stepping do not work. The value of this 405 symbol should be set to the TLB1 entry to be used for this 406 purpose. 407 408 CONFIG_SYS_FSL_ERRATUM_A004510 409 410 Enables a workaround for erratum A004510. If set, 411 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 412 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 413 414 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 415 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 416 417 Defines one or two SoC revisions (low 8 bits of SVR) 418 for which the A004510 workaround should be applied. 419 420 The rest of SVR is either not relevant to the decision 421 of whether the erratum is present (e.g. p2040 versus 422 p2041) or is implied by the build target, which controls 423 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 424 425 See Freescale App Note 4493 for more information about 426 this erratum. 427 428 CONFIG_A003399_NOR_WORKAROUND 429 Enables a workaround for IFC erratum A003399. It is only 430 required during NOR boot. 431 432 CONFIG_A008044_WORKAROUND 433 Enables a workaround for T1040/T1042 erratum A008044. It is only 434 required during NAND boot and valid for Rev 1.0 SoC revision 435 436 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 437 438 This is the value to write into CCSR offset 0x18600 439 according to the A004510 workaround. 440 441 CONFIG_SYS_FSL_DSP_DDR_ADDR 442 This value denotes start offset of DDR memory which is 443 connected exclusively to the DSP cores. 444 445 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 446 This value denotes start offset of M2 memory 447 which is directly connected to the DSP core. 448 449 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 450 This value denotes start offset of M3 memory which is directly 451 connected to the DSP core. 452 453 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 454 This value denotes start offset of DSP CCSR space. 455 456 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 457 Single Source Clock is clocking mode present in some of FSL SoC's. 458 In this mode, a single differential clock is used to supply 459 clocks to the sysclock, ddrclock and usbclock. 460 461 CONFIG_SYS_CPC_REINIT_F 462 This CONFIG is defined when the CPC is configured as SRAM at the 463 time of U-Boot entry and is required to be re-initialized. 464 465 CONFIG_DEEP_SLEEP 466 Indicates this SoC supports deep sleep feature. If deep sleep is 467 supported, core will start to execute uboot when wakes up. 468 469- Generic CPU options: 470 CONFIG_SYS_GENERIC_GLOBAL_DATA 471 Defines global data is initialized in generic board board_init_f(). 472 If this macro is defined, global data is created and cleared in 473 generic board board_init_f(). Without this macro, architecture/board 474 should initialize global data before calling board_init_f(). 475 476 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 477 478 Defines the endianess of the CPU. Implementation of those 479 values is arch specific. 480 481 CONFIG_SYS_FSL_DDR 482 Freescale DDR driver in use. This type of DDR controller is 483 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 484 SoCs. 485 486 CONFIG_SYS_FSL_DDR_ADDR 487 Freescale DDR memory-mapped register base. 488 489 CONFIG_SYS_FSL_DDR_EMU 490 Specify emulator support for DDR. Some DDR features such as 491 deskew training are not available. 492 493 CONFIG_SYS_FSL_DDRC_GEN1 494 Freescale DDR1 controller. 495 496 CONFIG_SYS_FSL_DDRC_GEN2 497 Freescale DDR2 controller. 498 499 CONFIG_SYS_FSL_DDRC_GEN3 500 Freescale DDR3 controller. 501 502 CONFIG_SYS_FSL_DDRC_GEN4 503 Freescale DDR4 controller. 504 505 CONFIG_SYS_FSL_DDRC_ARM_GEN3 506 Freescale DDR3 controller for ARM-based SoCs. 507 508 CONFIG_SYS_FSL_DDR1 509 Board config to use DDR1. It can be enabled for SoCs with 510 Freescale DDR1 or DDR2 controllers, depending on the board 511 implemetation. 512 513 CONFIG_SYS_FSL_DDR2 514 Board config to use DDR2. It can be eanbeld for SoCs with 515 Freescale DDR2 or DDR3 controllers, depending on the board 516 implementation. 517 518 CONFIG_SYS_FSL_DDR3 519 Board config to use DDR3. It can be enabled for SoCs with 520 Freescale DDR3 or DDR3L controllers. 521 522 CONFIG_SYS_FSL_DDR3L 523 Board config to use DDR3L. It can be enabled for SoCs with 524 DDR3L controllers. 525 526 CONFIG_SYS_FSL_DDR4 527 Board config to use DDR4. It can be enabled for SoCs with 528 DDR4 controllers. 529 530 CONFIG_SYS_FSL_IFC_BE 531 Defines the IFC controller register space as Big Endian 532 533 CONFIG_SYS_FSL_IFC_LE 534 Defines the IFC controller register space as Little Endian 535 536 CONFIG_SYS_FSL_PBL_PBI 537 It enables addition of RCW (Power on reset configuration) in built image. 538 Please refer doc/README.pblimage for more details 539 540 CONFIG_SYS_FSL_PBL_RCW 541 It adds PBI(pre-boot instructions) commands in u-boot build image. 542 PBI commands can be used to configure SoC before it starts the execution. 543 Please refer doc/README.pblimage for more details 544 545 CONFIG_SPL_FSL_PBL 546 It adds a target to create boot binary having SPL binary in PBI format 547 concatenated with u-boot binary. 548 549 CONFIG_SYS_FSL_DDR_BE 550 Defines the DDR controller register space as Big Endian 551 552 CONFIG_SYS_FSL_DDR_LE 553 Defines the DDR controller register space as Little Endian 554 555 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 556 Physical address from the view of DDR controllers. It is the 557 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 558 it could be different for ARM SoCs. 559 560 CONFIG_SYS_FSL_DDR_INTLV_256B 561 DDR controller interleaving on 256-byte. This is a special 562 interleaving mode, handled by Dickens for Freescale layerscape 563 SoCs with ARM core. 564 565 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 566 Number of controllers used as main memory. 567 568 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 569 Number of controllers used for other than main memory. 570 571 CONFIG_SYS_FSL_HAS_DP_DDR 572 Defines the SoC has DP-DDR used for DPAA. 573 574 CONFIG_SYS_FSL_SEC_BE 575 Defines the SEC controller register space as Big Endian 576 577 CONFIG_SYS_FSL_SEC_LE 578 Defines the SEC controller register space as Little Endian 579 580- Intel Monahans options: 581 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 582 583 Defines the Monahans run mode to oscillator 584 ratio. Valid values are 8, 16, 24, 31. The core 585 frequency is this value multiplied by 13 MHz. 586 587 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 588 589 Defines the Monahans turbo mode to oscillator 590 ratio. Valid values are 1 (default if undefined) and 591 2. The core frequency as calculated above is multiplied 592 by this value. 593 594- MIPS CPU options: 595 CONFIG_SYS_INIT_SP_OFFSET 596 597 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 598 pointer. This is needed for the temporary stack before 599 relocation. 600 601 CONFIG_SYS_MIPS_CACHE_MODE 602 603 Cache operation mode for the MIPS CPU. 604 See also arch/mips/include/asm/mipsregs.h. 605 Possible values are: 606 CONF_CM_CACHABLE_NO_WA 607 CONF_CM_CACHABLE_WA 608 CONF_CM_UNCACHED 609 CONF_CM_CACHABLE_NONCOHERENT 610 CONF_CM_CACHABLE_CE 611 CONF_CM_CACHABLE_COW 612 CONF_CM_CACHABLE_CUW 613 CONF_CM_CACHABLE_ACCELERATED 614 615 CONFIG_SYS_XWAY_EBU_BOOTCFG 616 617 Special option for Lantiq XWAY SoCs for booting from NOR flash. 618 See also arch/mips/cpu/mips32/start.S. 619 620 CONFIG_XWAY_SWAP_BYTES 621 622 Enable compilation of tools/xway-swap-bytes needed for Lantiq 623 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 624 be swapped if a flash programmer is used. 625 626- ARM options: 627 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 628 629 Select high exception vectors of the ARM core, e.g., do not 630 clear the V bit of the c1 register of CP15. 631 632 CONFIG_SYS_THUMB_BUILD 633 634 Use this flag to build U-Boot using the Thumb instruction 635 set for ARM architectures. Thumb instruction set provides 636 better code density. For ARM architectures that support 637 Thumb2 this flag will result in Thumb2 code generated by 638 GCC. 639 640 CONFIG_ARM_ERRATA_716044 641 CONFIG_ARM_ERRATA_742230 642 CONFIG_ARM_ERRATA_743622 643 CONFIG_ARM_ERRATA_751472 644 CONFIG_ARM_ERRATA_761320 645 CONFIG_ARM_ERRATA_773022 646 CONFIG_ARM_ERRATA_774769 647 CONFIG_ARM_ERRATA_794072 648 649 If set, the workarounds for these ARM errata are applied early 650 during U-Boot startup. Note that these options force the 651 workarounds to be applied; no CPU-type/version detection 652 exists, unlike the similar options in the Linux kernel. Do not 653 set these options unless they apply! 654 655 COUNTER_FREQUENCY 656 Generic timer clock source frequency. 657 658 COUNTER_FREQUENCY_REAL 659 Generic timer clock source frequency if the real clock is 660 different from COUNTER_FREQUENCY, and can only be determined 661 at run time. 662 663 NOTE: The following can be machine specific errata. These 664 do have ability to provide rudimentary version and machine 665 specific checks, but expect no product checks. 666 CONFIG_ARM_ERRATA_430973 667 CONFIG_ARM_ERRATA_454179 668 CONFIG_ARM_ERRATA_621766 669 CONFIG_ARM_ERRATA_798870 670 CONFIG_ARM_ERRATA_801819 671 672- Tegra SoC options: 673 CONFIG_TEGRA_SUPPORT_NON_SECURE 674 675 Support executing U-Boot in non-secure (NS) mode. Certain 676 impossible actions will be skipped if the CPU is in NS mode, 677 such as ARM architectural timer initialization. 678 679- Linux Kernel Interface: 680 CONFIG_CLOCKS_IN_MHZ 681 682 U-Boot stores all clock information in Hz 683 internally. For binary compatibility with older Linux 684 kernels (which expect the clocks passed in the 685 bd_info data to be in MHz) the environment variable 686 "clocks_in_mhz" can be defined so that U-Boot 687 converts clock data to MHZ before passing it to the 688 Linux kernel. 689 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 690 "clocks_in_mhz=1" is automatically included in the 691 default environment. 692 693 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 694 695 When transferring memsize parameter to Linux, some versions 696 expect it to be in bytes, others in MB. 697 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 698 699 CONFIG_OF_LIBFDT 700 701 New kernel versions are expecting firmware settings to be 702 passed using flattened device trees (based on open firmware 703 concepts). 704 705 CONFIG_OF_LIBFDT 706 * New libfdt-based support 707 * Adds the "fdt" command 708 * The bootm command automatically updates the fdt 709 710 OF_CPU - The proper name of the cpus node (only required for 711 MPC512X and MPC5xxx based boards). 712 OF_SOC - The proper name of the soc node (only required for 713 MPC512X and MPC5xxx based boards). 714 OF_TBCLK - The timebase frequency. 715 OF_STDOUT_PATH - The path to the console device 716 717 boards with QUICC Engines require OF_QE to set UCC MAC 718 addresses 719 720 CONFIG_OF_BOARD_SETUP 721 722 Board code has addition modification that it wants to make 723 to the flat device tree before handing it off to the kernel 724 725 CONFIG_OF_SYSTEM_SETUP 726 727 Other code has addition modification that it wants to make 728 to the flat device tree before handing it off to the kernel. 729 This causes ft_system_setup() to be called before booting 730 the kernel. 731 732 CONFIG_OF_BOOT_CPU 733 734 This define fills in the correct boot CPU in the boot 735 param header, the default value is zero if undefined. 736 737 CONFIG_OF_IDE_FIXUP 738 739 U-Boot can detect if an IDE device is present or not. 740 If not, and this new config option is activated, U-Boot 741 removes the ATA node from the DTS before booting Linux, 742 so the Linux IDE driver does not probe the device and 743 crash. This is needed for buggy hardware (uc101) where 744 no pull down resistor is connected to the signal IDE5V_DD7. 745 746 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 747 748 This setting is mandatory for all boards that have only one 749 machine type and must be used to specify the machine type 750 number as it appears in the ARM machine registry 751 (see http://www.arm.linux.org.uk/developer/machines/). 752 Only boards that have multiple machine types supported 753 in a single configuration file and the machine type is 754 runtime discoverable, do not have to use this setting. 755 756- vxWorks boot parameters: 757 758 bootvx constructs a valid bootline using the following 759 environments variables: bootdev, bootfile, ipaddr, netmask, 760 serverip, gatewayip, hostname, othbootargs. 761 It loads the vxWorks image pointed bootfile. 762 763 Note: If a "bootargs" environment is defined, it will overwride 764 the defaults discussed just above. 765 766- Cache Configuration: 767 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 768 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 769 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 770 771- Cache Configuration for ARM: 772 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 773 controller 774 CONFIG_SYS_PL310_BASE - Physical base address of PL310 775 controller register space 776 777- Serial Ports: 778 CONFIG_PL010_SERIAL 779 780 Define this if you want support for Amba PrimeCell PL010 UARTs. 781 782 CONFIG_PL011_SERIAL 783 784 Define this if you want support for Amba PrimeCell PL011 UARTs. 785 786 CONFIG_PL011_CLOCK 787 788 If you have Amba PrimeCell PL011 UARTs, set this variable to 789 the clock speed of the UARTs. 790 791 CONFIG_PL01x_PORTS 792 793 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 794 define this to a list of base addresses for each (supported) 795 port. See e.g. include/configs/versatile.h 796 797 CONFIG_SERIAL_HW_FLOW_CONTROL 798 799 Define this variable to enable hw flow control in serial driver. 800 Current user of this option is drivers/serial/nsl16550.c driver 801 802- Console Interface: 803 Depending on board, define exactly one serial port 804 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 805 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 806 console by defining CONFIG_8xx_CONS_NONE 807 808 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 809 port routines must be defined elsewhere 810 (i.e. serial_init(), serial_getc(), ...) 811 812 CONFIG_CFB_CONSOLE 813 Enables console device for a color framebuffer. Needs following 814 defines (cf. smiLynxEM, i8042) 815 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 816 (default big endian) 817 VIDEO_HW_RECTFILL graphic chip supports 818 rectangle fill 819 (cf. smiLynxEM) 820 VIDEO_HW_BITBLT graphic chip supports 821 bit-blit (cf. smiLynxEM) 822 VIDEO_VISIBLE_COLS visible pixel columns 823 (cols=pitch) 824 VIDEO_VISIBLE_ROWS visible pixel rows 825 VIDEO_PIXEL_SIZE bytes per pixel 826 VIDEO_DATA_FORMAT graphic data format 827 (0-5, cf. cfb_console.c) 828 VIDEO_FB_ADRS framebuffer address 829 VIDEO_KBD_INIT_FCT keyboard int fct 830 (i.e. rx51_kp_init()) 831 VIDEO_TSTC_FCT test char fct 832 (i.e. rx51_kp_tstc) 833 VIDEO_GETC_FCT get char fct 834 (i.e. rx51_kp_getc) 835 CONFIG_VIDEO_LOGO display Linux logo in 836 upper left corner 837 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 838 linux_logo.h for logo. 839 Requires CONFIG_VIDEO_LOGO 840 CONFIG_CONSOLE_EXTRA_INFO 841 additional board info beside 842 the logo 843 844 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 845 a limited number of ANSI escape sequences (cursor control, 846 erase functions and limited graphics rendition control). 847 848 When CONFIG_CFB_CONSOLE is defined, video console is 849 default i/o. Serial console can be forced with 850 environment 'console=serial'. 851 852 When CONFIG_SILENT_CONSOLE is defined, all console 853 messages (by U-Boot and Linux!) can be silenced with 854 the "silent" environment variable. See 855 doc/README.silent for more information. 856 857 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 858 is 0x00. 859 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 860 is 0xa0. 861 862- Console Baudrate: 863 CONFIG_BAUDRATE - in bps 864 Select one of the baudrates listed in 865 CONFIG_SYS_BAUDRATE_TABLE, see below. 866 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 867 868- Console Rx buffer length 869 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 870 the maximum receive buffer length for the SMC. 871 This option is actual only for 82xx and 8xx possible. 872 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 873 must be defined, to setup the maximum idle timeout for 874 the SMC. 875 876- Pre-Console Buffer: 877 Prior to the console being initialised (i.e. serial UART 878 initialised etc) all console output is silently discarded. 879 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 880 buffer any console messages prior to the console being 881 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 882 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 883 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 884 bytes are output before the console is initialised, the 885 earlier bytes are discarded. 886 887 Note that when printing the buffer a copy is made on the 888 stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack. 889 890 'Sane' compilers will generate smaller code if 891 CONFIG_PRE_CON_BUF_SZ is a power of 2 892 893- Boot Delay: CONFIG_BOOTDELAY - in seconds 894 Delay before automatically booting the default image; 895 set to -1 to disable autoboot. 896 set to -2 to autoboot with no delay and not check for abort 897 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 898 899 See doc/README.autoboot for these options that 900 work with CONFIG_BOOTDELAY. None are required. 901 CONFIG_BOOT_RETRY_TIME 902 CONFIG_BOOT_RETRY_MIN 903 CONFIG_AUTOBOOT_KEYED 904 CONFIG_AUTOBOOT_PROMPT 905 CONFIG_AUTOBOOT_DELAY_STR 906 CONFIG_AUTOBOOT_STOP_STR 907 CONFIG_ZERO_BOOTDELAY_CHECK 908 CONFIG_RESET_TO_RETRY 909 910- Autoboot Command: 911 CONFIG_BOOTCOMMAND 912 Only needed when CONFIG_BOOTDELAY is enabled; 913 define a command string that is automatically executed 914 when no character is read on the console interface 915 within "Boot Delay" after reset. 916 917 CONFIG_BOOTARGS 918 This can be used to pass arguments to the bootm 919 command. The value of CONFIG_BOOTARGS goes into the 920 environment value "bootargs". 921 922 CONFIG_RAMBOOT and CONFIG_NFSBOOT 923 The value of these goes into the environment as 924 "ramboot" and "nfsboot" respectively, and can be used 925 as a convenience, when switching between booting from 926 RAM and NFS. 927 928- Bootcount: 929 CONFIG_BOOTCOUNT_LIMIT 930 Implements a mechanism for detecting a repeating reboot 931 cycle, see: 932 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 933 934 CONFIG_BOOTCOUNT_ENV 935 If no softreset save registers are found on the hardware 936 "bootcount" is stored in the environment. To prevent a 937 saveenv on all reboots, the environment variable 938 "upgrade_available" is used. If "upgrade_available" is 939 0, "bootcount" is always 0, if "upgrade_available" is 940 1 "bootcount" is incremented in the environment. 941 So the Userspace Applikation must set the "upgrade_available" 942 and "bootcount" variable to 0, if a boot was successfully. 943 944- Pre-Boot Commands: 945 CONFIG_PREBOOT 946 947 When this option is #defined, the existence of the 948 environment variable "preboot" will be checked 949 immediately before starting the CONFIG_BOOTDELAY 950 countdown and/or running the auto-boot command resp. 951 entering interactive mode. 952 953 This feature is especially useful when "preboot" is 954 automatically generated or modified. For an example 955 see the LWMON board specific code: here "preboot" is 956 modified when the user holds down a certain 957 combination of keys on the (special) keyboard when 958 booting the systems 959 960- Serial Download Echo Mode: 961 CONFIG_LOADS_ECHO 962 If defined to 1, all characters received during a 963 serial download (using the "loads" command) are 964 echoed back. This might be needed by some terminal 965 emulations (like "cu"), but may as well just take 966 time on others. This setting #define's the initial 967 value of the "loads_echo" environment variable. 968 969- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 970 CONFIG_KGDB_BAUDRATE 971 Select one of the baudrates listed in 972 CONFIG_SYS_BAUDRATE_TABLE, see below. 973 974- Monitor Functions: 975 Monitor commands can be included or excluded 976 from the build by using the #include files 977 <config_cmd_all.h> and #undef'ing unwanted 978 commands, or adding #define's for wanted commands. 979 980 The default command configuration includes all commands 981 except those marked below with a "*". 982 983 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 984 CONFIG_CMD_ASKENV * ask for env variable 985 CONFIG_CMD_BDI bdinfo 986 CONFIG_CMD_BEDBUG * Include BedBug Debugger 987 CONFIG_CMD_BMP * BMP support 988 CONFIG_CMD_BSP * Board specific commands 989 CONFIG_CMD_BOOTD bootd 990 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 991 CONFIG_CMD_CACHE * icache, dcache 992 CONFIG_CMD_CLK * clock command support 993 CONFIG_CMD_CONSOLE coninfo 994 CONFIG_CMD_CRC32 * crc32 995 CONFIG_CMD_DATE * support for RTC, date/time... 996 CONFIG_CMD_DHCP * DHCP support 997 CONFIG_CMD_DIAG * Diagnostics 998 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 999 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1000 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1001 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1002 CONFIG_CMD_DTT * Digital Therm and Thermostat 1003 CONFIG_CMD_ECHO echo arguments 1004 CONFIG_CMD_EDITENV edit env variable 1005 CONFIG_CMD_EEPROM * EEPROM read/write support 1006 CONFIG_CMD_ELF * bootelf, bootvx 1007 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1008 CONFIG_CMD_ENV_FLAGS * display details about env flags 1009 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1010 CONFIG_CMD_EXPORTENV * export the environment 1011 CONFIG_CMD_EXT2 * ext2 command support 1012 CONFIG_CMD_EXT4 * ext4 command support 1013 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1014 that work for multiple fs types 1015 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1016 CONFIG_CMD_SAVEENV saveenv 1017 CONFIG_CMD_FDC * Floppy Disk Support 1018 CONFIG_CMD_FAT * FAT command support 1019 CONFIG_CMD_FLASH flinfo, erase, protect 1020 CONFIG_CMD_FPGA FPGA device initialization support 1021 CONFIG_CMD_FUSE * Device fuse support 1022 CONFIG_CMD_GETTIME * Get time since boot 1023 CONFIG_CMD_GO * the 'go' command (exec code) 1024 CONFIG_CMD_GREPENV * search environment 1025 CONFIG_CMD_HASH * calculate hash / digest 1026 CONFIG_CMD_I2C * I2C serial bus support 1027 CONFIG_CMD_IDE * IDE harddisk support 1028 CONFIG_CMD_IMI iminfo 1029 CONFIG_CMD_IMLS List all images found in NOR flash 1030 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1031 CONFIG_CMD_IMMAP * IMMR dump support 1032 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1033 CONFIG_CMD_IMPORTENV * import an environment 1034 CONFIG_CMD_INI * import data from an ini file into the env 1035 CONFIG_CMD_IRQ * irqinfo 1036 CONFIG_CMD_ITEST Integer/string test of 2 values 1037 CONFIG_CMD_JFFS2 * JFFS2 Support 1038 CONFIG_CMD_KGDB * kgdb 1039 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1040 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1041 (169.254.*.*) 1042 CONFIG_CMD_LOADB loadb 1043 CONFIG_CMD_LOADS loads 1044 CONFIG_CMD_MD5SUM * print md5 message digest 1045 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1046 CONFIG_CMD_MEMINFO * Display detailed memory information 1047 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1048 loop, loopw 1049 CONFIG_CMD_MEMTEST * mtest 1050 CONFIG_CMD_MISC Misc functions like sleep etc 1051 CONFIG_CMD_MMC * MMC memory mapped support 1052 CONFIG_CMD_MII * MII utility commands 1053 CONFIG_CMD_MTDPARTS * MTD partition support 1054 CONFIG_CMD_NAND * NAND support 1055 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1056 CONFIG_CMD_NFS NFS support 1057 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1058 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1059 CONFIG_CMD_PCI * pciinfo 1060 CONFIG_CMD_PCMCIA * PCMCIA support 1061 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1062 host 1063 CONFIG_CMD_PORTIO * Port I/O 1064 CONFIG_CMD_READ * Read raw data from partition 1065 CONFIG_CMD_REGINFO * Register dump 1066 CONFIG_CMD_RUN run command in env variable 1067 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1068 CONFIG_CMD_SAVES * save S record dump 1069 CONFIG_SCSI * SCSI Support 1070 CONFIG_CMD_SDRAM * print SDRAM configuration information 1071 (requires CONFIG_CMD_I2C) 1072 CONFIG_CMD_SETGETDCR Support for DCR Register access 1073 (4xx only) 1074 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1075 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1076 (requires CONFIG_CMD_MEMORY) 1077 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1078 CONFIG_CMD_SOURCE "source" command Support 1079 CONFIG_CMD_SPI * SPI serial bus support 1080 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1081 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1082 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1083 CONFIG_CMD_TIMER * access to the system tick timer 1084 CONFIG_CMD_USB * USB support 1085 CONFIG_CMD_CDP * Cisco Discover Protocol support 1086 CONFIG_CMD_MFSL * Microblaze FSL support 1087 CONFIG_CMD_XIMG Load part of Multi Image 1088 CONFIG_CMD_UUID * Generate random UUID or GUID string 1089 1090 EXAMPLE: If you want all functions except of network 1091 support you can write: 1092 1093 #include "config_cmd_all.h" 1094 #undef CONFIG_CMD_NET 1095 1096 Other Commands: 1097 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1098 1099 Note: Don't enable the "icache" and "dcache" commands 1100 (configuration option CONFIG_CMD_CACHE) unless you know 1101 what you (and your U-Boot users) are doing. Data 1102 cache cannot be enabled on systems like the 8xx or 1103 8260 (where accesses to the IMMR region must be 1104 uncached), and it cannot be disabled on all other 1105 systems where we (mis-) use the data cache to hold an 1106 initial stack and some data. 1107 1108 1109 XXX - this list needs to get updated! 1110 1111- Removal of commands 1112 If no commands are needed to boot, you can disable 1113 CONFIG_CMDLINE to remove them. In this case, the command line 1114 will not be available, and when U-Boot wants to execute the 1115 boot command (on start-up) it will call board_run_command() 1116 instead. This can reduce image size significantly for very 1117 simple boot procedures. 1118 1119- Regular expression support: 1120 CONFIG_REGEX 1121 If this variable is defined, U-Boot is linked against 1122 the SLRE (Super Light Regular Expression) library, 1123 which adds regex support to some commands, as for 1124 example "env grep" and "setexpr". 1125 1126- Device tree: 1127 CONFIG_OF_CONTROL 1128 If this variable is defined, U-Boot will use a device tree 1129 to configure its devices, instead of relying on statically 1130 compiled #defines in the board file. This option is 1131 experimental and only available on a few boards. The device 1132 tree is available in the global data as gd->fdt_blob. 1133 1134 U-Boot needs to get its device tree from somewhere. This can 1135 be done using one of the two options below: 1136 1137 CONFIG_OF_EMBED 1138 If this variable is defined, U-Boot will embed a device tree 1139 binary in its image. This device tree file should be in the 1140 board directory and called <soc>-<board>.dts. The binary file 1141 is then picked up in board_init_f() and made available through 1142 the global data structure as gd->blob. 1143 1144 CONFIG_OF_SEPARATE 1145 If this variable is defined, U-Boot will build a device tree 1146 binary. It will be called u-boot.dtb. Architecture-specific 1147 code will locate it at run-time. Generally this works by: 1148 1149 cat u-boot.bin u-boot.dtb >image.bin 1150 1151 and in fact, U-Boot does this for you, creating a file called 1152 u-boot-dtb.bin which is useful in the common case. You can 1153 still use the individual files if you need something more 1154 exotic. 1155 1156- Watchdog: 1157 CONFIG_WATCHDOG 1158 If this variable is defined, it enables watchdog 1159 support for the SoC. There must be support in the SoC 1160 specific code for a watchdog. For the 8xx and 8260 1161 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1162 register. When supported for a specific SoC is 1163 available, then no further board specific code should 1164 be needed to use it. 1165 1166 CONFIG_HW_WATCHDOG 1167 When using a watchdog circuitry external to the used 1168 SoC, then define this variable and provide board 1169 specific code for the "hw_watchdog_reset" function. 1170 1171 CONFIG_AT91_HW_WDT_TIMEOUT 1172 specify the timeout in seconds. default 2 seconds. 1173 1174- U-Boot Version: 1175 CONFIG_VERSION_VARIABLE 1176 If this variable is defined, an environment variable 1177 named "ver" is created by U-Boot showing the U-Boot 1178 version as printed by the "version" command. 1179 Any change to this variable will be reverted at the 1180 next reset. 1181 1182- Real-Time Clock: 1183 1184 When CONFIG_CMD_DATE is selected, the type of the RTC 1185 has to be selected, too. Define exactly one of the 1186 following options: 1187 1188 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1189 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1190 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1191 CONFIG_RTC_MC146818 - use MC146818 RTC 1192 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1193 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1194 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1195 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1196 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1197 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1198 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1199 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1200 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1201 RV3029 RTC. 1202 1203 Note that if the RTC uses I2C, then the I2C interface 1204 must also be configured. See I2C Support, below. 1205 1206- GPIO Support: 1207 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1208 1209 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1210 chip-ngpio pairs that tell the PCA953X driver the number of 1211 pins supported by a particular chip. 1212 1213 Note that if the GPIO device uses I2C, then the I2C interface 1214 must also be configured. See I2C Support, below. 1215 1216- I/O tracing: 1217 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1218 accesses and can checksum them or write a list of them out 1219 to memory. See the 'iotrace' command for details. This is 1220 useful for testing device drivers since it can confirm that 1221 the driver behaves the same way before and after a code 1222 change. Currently this is supported on sandbox and arm. To 1223 add support for your architecture, add '#include <iotrace.h>' 1224 to the bottom of arch/<arch>/include/asm/io.h and test. 1225 1226 Example output from the 'iotrace stats' command is below. 1227 Note that if the trace buffer is exhausted, the checksum will 1228 still continue to operate. 1229 1230 iotrace is enabled 1231 Start: 10000000 (buffer start address) 1232 Size: 00010000 (buffer size) 1233 Offset: 00000120 (current buffer offset) 1234 Output: 10000120 (start + offset) 1235 Count: 00000018 (number of trace records) 1236 CRC32: 9526fb66 (CRC32 of all trace records) 1237 1238- Timestamp Support: 1239 1240 When CONFIG_TIMESTAMP is selected, the timestamp 1241 (date and time) of an image is printed by image 1242 commands like bootm or iminfo. This option is 1243 automatically enabled when you select CONFIG_CMD_DATE . 1244 1245- Partition Labels (disklabels) Supported: 1246 Zero or more of the following: 1247 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1248 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1249 Intel architecture, USB sticks, etc. 1250 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1251 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1252 bootloader. Note 2TB partition limit; see 1253 disk/part_efi.c 1254 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1255 1256 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1257 CONFIG_SCSI) you must configure support for at 1258 least one non-MTD partition type as well. 1259 1260- IDE Reset method: 1261 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1262 board configurations files but used nowhere! 1263 1264 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1265 be performed by calling the function 1266 ide_set_reset(int reset) 1267 which has to be defined in a board specific file 1268 1269- ATAPI Support: 1270 CONFIG_ATAPI 1271 1272 Set this to enable ATAPI support. 1273 1274- LBA48 Support 1275 CONFIG_LBA48 1276 1277 Set this to enable support for disks larger than 137GB 1278 Also look at CONFIG_SYS_64BIT_LBA. 1279 Whithout these , LBA48 support uses 32bit variables and will 'only' 1280 support disks up to 2.1TB. 1281 1282 CONFIG_SYS_64BIT_LBA: 1283 When enabled, makes the IDE subsystem use 64bit sector addresses. 1284 Default is 32bit. 1285 1286- SCSI Support: 1287 At the moment only there is only support for the 1288 SYM53C8XX SCSI controller; define 1289 CONFIG_SCSI_SYM53C8XX to enable it. 1290 1291 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1292 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1293 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1294 maximum numbers of LUNs, SCSI ID's and target 1295 devices. 1296 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1297 1298 The environment variable 'scsidevs' is set to the number of 1299 SCSI devices found during the last scan. 1300 1301- NETWORK Support (PCI): 1302 CONFIG_E1000 1303 Support for Intel 8254x/8257x gigabit chips. 1304 1305 CONFIG_E1000_SPI 1306 Utility code for direct access to the SPI bus on Intel 8257x. 1307 This does not do anything useful unless you set at least one 1308 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1309 1310 CONFIG_E1000_SPI_GENERIC 1311 Allow generic access to the SPI bus on the Intel 8257x, for 1312 example with the "sspi" command. 1313 1314 CONFIG_CMD_E1000 1315 Management command for E1000 devices. When used on devices 1316 with SPI support you can reprogram the EEPROM from U-Boot. 1317 1318 CONFIG_EEPRO100 1319 Support for Intel 82557/82559/82559ER chips. 1320 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1321 write routine for first time initialisation. 1322 1323 CONFIG_TULIP 1324 Support for Digital 2114x chips. 1325 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1326 modem chip initialisation (KS8761/QS6611). 1327 1328 CONFIG_NATSEMI 1329 Support for National dp83815 chips. 1330 1331 CONFIG_NS8382X 1332 Support for National dp8382[01] gigabit chips. 1333 1334- NETWORK Support (other): 1335 1336 CONFIG_DRIVER_AT91EMAC 1337 Support for AT91RM9200 EMAC. 1338 1339 CONFIG_RMII 1340 Define this to use reduced MII inteface 1341 1342 CONFIG_DRIVER_AT91EMAC_QUIET 1343 If this defined, the driver is quiet. 1344 The driver doen't show link status messages. 1345 1346 CONFIG_CALXEDA_XGMAC 1347 Support for the Calxeda XGMAC device 1348 1349 CONFIG_LAN91C96 1350 Support for SMSC's LAN91C96 chips. 1351 1352 CONFIG_LAN91C96_BASE 1353 Define this to hold the physical address 1354 of the LAN91C96's I/O space 1355 1356 CONFIG_LAN91C96_USE_32_BIT 1357 Define this to enable 32 bit addressing 1358 1359 CONFIG_SMC91111 1360 Support for SMSC's LAN91C111 chip 1361 1362 CONFIG_SMC91111_BASE 1363 Define this to hold the physical address 1364 of the device (I/O space) 1365 1366 CONFIG_SMC_USE_32_BIT 1367 Define this if data bus is 32 bits 1368 1369 CONFIG_SMC_USE_IOFUNCS 1370 Define this to use i/o functions instead of macros 1371 (some hardware wont work with macros) 1372 1373 CONFIG_DRIVER_TI_EMAC 1374 Support for davinci emac 1375 1376 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1377 Define this if you have more then 3 PHYs. 1378 1379 CONFIG_FTGMAC100 1380 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1381 1382 CONFIG_FTGMAC100_EGIGA 1383 Define this to use GE link update with gigabit PHY. 1384 Define this if FTGMAC100 is connected to gigabit PHY. 1385 If your system has 10/100 PHY only, it might not occur 1386 wrong behavior. Because PHY usually return timeout or 1387 useless data when polling gigabit status and gigabit 1388 control registers. This behavior won't affect the 1389 correctnessof 10/100 link speed update. 1390 1391 CONFIG_SMC911X 1392 Support for SMSC's LAN911x and LAN921x chips 1393 1394 CONFIG_SMC911X_BASE 1395 Define this to hold the physical address 1396 of the device (I/O space) 1397 1398 CONFIG_SMC911X_32_BIT 1399 Define this if data bus is 32 bits 1400 1401 CONFIG_SMC911X_16_BIT 1402 Define this if data bus is 16 bits. If your processor 1403 automatically converts one 32 bit word to two 16 bit 1404 words you may also try CONFIG_SMC911X_32_BIT. 1405 1406 CONFIG_SH_ETHER 1407 Support for Renesas on-chip Ethernet controller 1408 1409 CONFIG_SH_ETHER_USE_PORT 1410 Define the number of ports to be used 1411 1412 CONFIG_SH_ETHER_PHY_ADDR 1413 Define the ETH PHY's address 1414 1415 CONFIG_SH_ETHER_CACHE_WRITEBACK 1416 If this option is set, the driver enables cache flush. 1417 1418- PWM Support: 1419 CONFIG_PWM_IMX 1420 Support for PWM modul on the imx6. 1421 1422- TPM Support: 1423 CONFIG_TPM 1424 Support TPM devices. 1425 1426 CONFIG_TPM_TIS_INFINEON 1427 Support for Infineon i2c bus TPM devices. Only one device 1428 per system is supported at this time. 1429 1430 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1431 Define the burst count bytes upper limit 1432 1433 CONFIG_TPM_ST33ZP24 1434 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1435 1436 CONFIG_TPM_ST33ZP24_I2C 1437 Support for STMicroelectronics ST33ZP24 I2C devices. 1438 Requires TPM_ST33ZP24 and I2C. 1439 1440 CONFIG_TPM_ST33ZP24_SPI 1441 Support for STMicroelectronics ST33ZP24 SPI devices. 1442 Requires TPM_ST33ZP24 and SPI. 1443 1444 CONFIG_TPM_ATMEL_TWI 1445 Support for Atmel TWI TPM device. Requires I2C support. 1446 1447 CONFIG_TPM_TIS_LPC 1448 Support for generic parallel port TPM devices. Only one device 1449 per system is supported at this time. 1450 1451 CONFIG_TPM_TIS_BASE_ADDRESS 1452 Base address where the generic TPM device is mapped 1453 to. Contemporary x86 systems usually map it at 1454 0xfed40000. 1455 1456 CONFIG_CMD_TPM 1457 Add tpm monitor functions. 1458 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1459 provides monitor access to authorized functions. 1460 1461 CONFIG_TPM 1462 Define this to enable the TPM support library which provides 1463 functional interfaces to some TPM commands. 1464 Requires support for a TPM device. 1465 1466 CONFIG_TPM_AUTH_SESSIONS 1467 Define this to enable authorized functions in the TPM library. 1468 Requires CONFIG_TPM and CONFIG_SHA1. 1469 1470- USB Support: 1471 At the moment only the UHCI host controller is 1472 supported (PIP405, MIP405, MPC5200); define 1473 CONFIG_USB_UHCI to enable it. 1474 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1475 and define CONFIG_USB_STORAGE to enable the USB 1476 storage devices. 1477 Note: 1478 Supported are USB Keyboards and USB Floppy drives 1479 (TEAC FD-05PUB). 1480 MPC5200 USB requires additional defines: 1481 CONFIG_USB_CLOCK 1482 for 528 MHz Clock: 0x0001bbbb 1483 CONFIG_PSC3_USB 1484 for USB on PSC3 1485 CONFIG_USB_CONFIG 1486 for differential drivers: 0x00001000 1487 for single ended drivers: 0x00005000 1488 for differential drivers on PSC3: 0x00000100 1489 for single ended drivers on PSC3: 0x00004100 1490 CONFIG_SYS_USB_EVENT_POLL 1491 May be defined to allow interrupt polling 1492 instead of using asynchronous interrupts 1493 1494 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1495 txfilltuning field in the EHCI controller on reset. 1496 1497 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1498 HW module registers. 1499 1500- USB Device: 1501 Define the below if you wish to use the USB console. 1502 Once firmware is rebuilt from a serial console issue the 1503 command "setenv stdin usbtty; setenv stdout usbtty" and 1504 attach your USB cable. The Unix command "dmesg" should print 1505 it has found a new device. The environment variable usbtty 1506 can be set to gserial or cdc_acm to enable your device to 1507 appear to a USB host as a Linux gserial device or a 1508 Common Device Class Abstract Control Model serial device. 1509 If you select usbtty = gserial you should be able to enumerate 1510 a Linux host by 1511 # modprobe usbserial vendor=0xVendorID product=0xProductID 1512 else if using cdc_acm, simply setting the environment 1513 variable usbtty to be cdc_acm should suffice. The following 1514 might be defined in YourBoardName.h 1515 1516 CONFIG_USB_DEVICE 1517 Define this to build a UDC device 1518 1519 CONFIG_USB_TTY 1520 Define this to have a tty type of device available to 1521 talk to the UDC device 1522 1523 CONFIG_USBD_HS 1524 Define this to enable the high speed support for usb 1525 device and usbtty. If this feature is enabled, a routine 1526 int is_usbd_high_speed(void) 1527 also needs to be defined by the driver to dynamically poll 1528 whether the enumeration has succeded at high speed or full 1529 speed. 1530 1531 CONFIG_SYS_CONSOLE_IS_IN_ENV 1532 Define this if you want stdin, stdout &/or stderr to 1533 be set to usbtty. 1534 1535 mpc8xx: 1536 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1537 Derive USB clock from external clock "blah" 1538 - CONFIG_SYS_USB_EXTC_CLK 0x02 1539 1540 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1541 Derive USB clock from brgclk 1542 - CONFIG_SYS_USB_BRG_CLK 0x04 1543 1544 If you have a USB-IF assigned VendorID then you may wish to 1545 define your own vendor specific values either in BoardName.h 1546 or directly in usbd_vendor_info.h. If you don't define 1547 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1548 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1549 should pretend to be a Linux device to it's target host. 1550 1551 CONFIG_USBD_MANUFACTURER 1552 Define this string as the name of your company for 1553 - CONFIG_USBD_MANUFACTURER "my company" 1554 1555 CONFIG_USBD_PRODUCT_NAME 1556 Define this string as the name of your product 1557 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1558 1559 CONFIG_USBD_VENDORID 1560 Define this as your assigned Vendor ID from the USB 1561 Implementors Forum. This *must* be a genuine Vendor ID 1562 to avoid polluting the USB namespace. 1563 - CONFIG_USBD_VENDORID 0xFFFF 1564 1565 CONFIG_USBD_PRODUCTID 1566 Define this as the unique Product ID 1567 for your device 1568 - CONFIG_USBD_PRODUCTID 0xFFFF 1569 1570- ULPI Layer Support: 1571 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1572 the generic ULPI layer. The generic layer accesses the ULPI PHY 1573 via the platform viewport, so you need both the genric layer and 1574 the viewport enabled. Currently only Chipidea/ARC based 1575 viewport is supported. 1576 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1577 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1578 If your ULPI phy needs a different reference clock than the 1579 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1580 the appropriate value in Hz. 1581 1582- MMC Support: 1583 The MMC controller on the Intel PXA is supported. To 1584 enable this define CONFIG_MMC. The MMC can be 1585 accessed from the boot prompt by mapping the device 1586 to physical memory similar to flash. Command line is 1587 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1588 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1589 1590 CONFIG_SH_MMCIF 1591 Support for Renesas on-chip MMCIF controller 1592 1593 CONFIG_SH_MMCIF_ADDR 1594 Define the base address of MMCIF registers 1595 1596 CONFIG_SH_MMCIF_CLK 1597 Define the clock frequency for MMCIF 1598 1599 CONFIG_GENERIC_MMC 1600 Enable the generic MMC driver 1601 1602 CONFIG_SUPPORT_EMMC_BOOT 1603 Enable some additional features of the eMMC boot partitions. 1604 1605 CONFIG_SUPPORT_EMMC_RPMB 1606 Enable the commands for reading, writing and programming the 1607 key for the Replay Protection Memory Block partition in eMMC. 1608 1609- USB Device Firmware Update (DFU) class support: 1610 CONFIG_USB_FUNCTION_DFU 1611 This enables the USB portion of the DFU USB class 1612 1613 CONFIG_CMD_DFU 1614 This enables the command "dfu" which is used to have 1615 U-Boot create a DFU class device via USB. This command 1616 requires that the "dfu_alt_info" environment variable be 1617 set and define the alt settings to expose to the host. 1618 1619 CONFIG_DFU_MMC 1620 This enables support for exposing (e)MMC devices via DFU. 1621 1622 CONFIG_DFU_NAND 1623 This enables support for exposing NAND devices via DFU. 1624 1625 CONFIG_DFU_RAM 1626 This enables support for exposing RAM via DFU. 1627 Note: DFU spec refer to non-volatile memory usage, but 1628 allow usages beyond the scope of spec - here RAM usage, 1629 one that would help mostly the developer. 1630 1631 CONFIG_SYS_DFU_DATA_BUF_SIZE 1632 Dfu transfer uses a buffer before writing data to the 1633 raw storage device. Make the size (in bytes) of this buffer 1634 configurable. The size of this buffer is also configurable 1635 through the "dfu_bufsiz" environment variable. 1636 1637 CONFIG_SYS_DFU_MAX_FILE_SIZE 1638 When updating files rather than the raw storage device, 1639 we use a static buffer to copy the file into and then write 1640 the buffer once we've been given the whole file. Define 1641 this to the maximum filesize (in bytes) for the buffer. 1642 Default is 4 MiB if undefined. 1643 1644 DFU_DEFAULT_POLL_TIMEOUT 1645 Poll timeout [ms], is the timeout a device can send to the 1646 host. The host must wait for this timeout before sending 1647 a subsequent DFU_GET_STATUS request to the device. 1648 1649 DFU_MANIFEST_POLL_TIMEOUT 1650 Poll timeout [ms], which the device sends to the host when 1651 entering dfuMANIFEST state. Host waits this timeout, before 1652 sending again an USB request to the device. 1653 1654- USB Device Android Fastboot support: 1655 CONFIG_USB_FUNCTION_FASTBOOT 1656 This enables the USB part of the fastboot gadget 1657 1658 CONFIG_CMD_FASTBOOT 1659 This enables the command "fastboot" which enables the Android 1660 fastboot mode for the platform's USB device. Fastboot is a USB 1661 protocol for downloading images, flashing and device control 1662 used on Android devices. 1663 See doc/README.android-fastboot for more information. 1664 1665 CONFIG_ANDROID_BOOT_IMAGE 1666 This enables support for booting images which use the Android 1667 image format header. 1668 1669 CONFIG_FASTBOOT_BUF_ADDR 1670 The fastboot protocol requires a large memory buffer for 1671 downloads. Define this to the starting RAM address to use for 1672 downloaded images. 1673 1674 CONFIG_FASTBOOT_BUF_SIZE 1675 The fastboot protocol requires a large memory buffer for 1676 downloads. This buffer should be as large as possible for a 1677 platform. Define this to the size available RAM for fastboot. 1678 1679 CONFIG_FASTBOOT_FLASH 1680 The fastboot protocol includes a "flash" command for writing 1681 the downloaded image to a non-volatile storage device. Define 1682 this to enable the "fastboot flash" command. 1683 1684 CONFIG_FASTBOOT_FLASH_MMC_DEV 1685 The fastboot "flash" command requires additional information 1686 regarding the non-volatile storage device. Define this to 1687 the eMMC device that fastboot should use to store the image. 1688 1689 CONFIG_FASTBOOT_GPT_NAME 1690 The fastboot "flash" command supports writing the downloaded 1691 image to the Protective MBR and the Primary GUID Partition 1692 Table. (Additionally, this downloaded image is post-processed 1693 to generate and write the Backup GUID Partition Table.) 1694 This occurs when the specified "partition name" on the 1695 "fastboot flash" command line matches this value. 1696 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1697 1698- Journaling Flash filesystem support: 1699 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1700 CONFIG_JFFS2_NAND_DEV 1701 Define these for a default partition on a NAND device 1702 1703 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1704 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1705 Define these for a default partition on a NOR device 1706 1707 CONFIG_SYS_JFFS_CUSTOM_PART 1708 Define this to create an own partition. You have to provide a 1709 function struct part_info* jffs2_part_info(int part_num) 1710 1711 If you define only one JFFS2 partition you may also want to 1712 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1713 to disable the command chpart. This is the default when you 1714 have not defined a custom partition 1715 1716- FAT(File Allocation Table) filesystem write function support: 1717 CONFIG_FAT_WRITE 1718 1719 Define this to enable support for saving memory data as a 1720 file in FAT formatted partition. 1721 1722 This will also enable the command "fatwrite" enabling the 1723 user to write files to FAT. 1724 1725CBFS (Coreboot Filesystem) support 1726 CONFIG_CMD_CBFS 1727 1728 Define this to enable support for reading from a Coreboot 1729 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1730 and cbfsload. 1731 1732- FAT(File Allocation Table) filesystem cluster size: 1733 CONFIG_FS_FAT_MAX_CLUSTSIZE 1734 1735 Define the max cluster size for fat operations else 1736 a default value of 65536 will be defined. 1737 1738- Keyboard Support: 1739 See Kconfig help for available keyboard drivers. 1740 1741 CONFIG_KEYBOARD 1742 1743 Define this to enable a custom keyboard support. 1744 This simply calls drv_keyboard_init() which must be 1745 defined in your board-specific files. This option is deprecated 1746 and is only used by novena. For new boards, use driver model 1747 instead. 1748 1749- Video support: 1750 CONFIG_VIDEO 1751 1752 Define this to enable video support (for output to 1753 video). 1754 1755 CONFIG_VIDEO_CT69000 1756 1757 Enable Chips & Technologies 69000 Video chip 1758 1759 CONFIG_VIDEO_SMI_LYNXEM 1760 Enable Silicon Motion SMI 712/710/810 Video chip. The 1761 video output is selected via environment 'videoout' 1762 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1763 assumed. 1764 1765 For the CT69000 and SMI_LYNXEM drivers, videomode is 1766 selected via environment 'videomode'. Two different ways 1767 are possible: 1768 - "videomode=num" 'num' is a standard LiLo mode numbers. 1769 Following standard modes are supported (* is default): 1770 1771 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1772 -------------+--------------------------------------------- 1773 8 bits | 0x301* 0x303 0x305 0x161 0x307 1774 15 bits | 0x310 0x313 0x316 0x162 0x319 1775 16 bits | 0x311 0x314 0x317 0x163 0x31A 1776 24 bits | 0x312 0x315 0x318 ? 0x31B 1777 -------------+--------------------------------------------- 1778 (i.e. setenv videomode 317; saveenv; reset;) 1779 1780 - "videomode=bootargs" all the video parameters are parsed 1781 from the bootargs. (See drivers/video/videomodes.c) 1782 1783 1784 CONFIG_VIDEO_SED13806 1785 Enable Epson SED13806 driver. This driver supports 8bpp 1786 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1787 or CONFIG_VIDEO_SED13806_16BPP 1788 1789 CONFIG_FSL_DIU_FB 1790 Enable the Freescale DIU video driver. Reference boards for 1791 SOCs that have a DIU should define this macro to enable DIU 1792 support, and should also define these other macros: 1793 1794 CONFIG_SYS_DIU_ADDR 1795 CONFIG_VIDEO 1796 CONFIG_CMD_BMP 1797 CONFIG_CFB_CONSOLE 1798 CONFIG_VIDEO_SW_CURSOR 1799 CONFIG_VGA_AS_SINGLE_DEVICE 1800 CONFIG_VIDEO_LOGO 1801 CONFIG_VIDEO_BMP_LOGO 1802 1803 The DIU driver will look for the 'video-mode' environment 1804 variable, and if defined, enable the DIU as a console during 1805 boot. See the documentation file doc/README.video for a 1806 description of this variable. 1807 1808- LCD Support: CONFIG_LCD 1809 1810 Define this to enable LCD support (for output to LCD 1811 display); also select one of the supported displays 1812 by defining one of these: 1813 1814 CONFIG_ATMEL_LCD: 1815 1816 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1817 1818 CONFIG_NEC_NL6448AC33: 1819 1820 NEC NL6448AC33-18. Active, color, single scan. 1821 1822 CONFIG_NEC_NL6448BC20 1823 1824 NEC NL6448BC20-08. 6.5", 640x480. 1825 Active, color, single scan. 1826 1827 CONFIG_NEC_NL6448BC33_54 1828 1829 NEC NL6448BC33-54. 10.4", 640x480. 1830 Active, color, single scan. 1831 1832 CONFIG_SHARP_16x9 1833 1834 Sharp 320x240. Active, color, single scan. 1835 It isn't 16x9, and I am not sure what it is. 1836 1837 CONFIG_SHARP_LQ64D341 1838 1839 Sharp LQ64D341 display, 640x480. 1840 Active, color, single scan. 1841 1842 CONFIG_HLD1045 1843 1844 HLD1045 display, 640x480. 1845 Active, color, single scan. 1846 1847 CONFIG_OPTREX_BW 1848 1849 Optrex CBL50840-2 NF-FW 99 22 M5 1850 or 1851 Hitachi LMG6912RPFC-00T 1852 or 1853 Hitachi SP14Q002 1854 1855 320x240. Black & white. 1856 1857 Normally display is black on white background; define 1858 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1859 1860 CONFIG_LCD_ALIGNMENT 1861 1862 Normally the LCD is page-aligned (typically 4KB). If this is 1863 defined then the LCD will be aligned to this value instead. 1864 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1865 here, since it is cheaper to change data cache settings on 1866 a per-section basis. 1867 1868 CONFIG_CONSOLE_SCROLL_LINES 1869 1870 When the console need to be scrolled, this is the number of 1871 lines to scroll by. It defaults to 1. Increasing this makes 1872 the console jump but can help speed up operation when scrolling 1873 is slow. 1874 1875 CONFIG_LCD_ROTATION 1876 1877 Sometimes, for example if the display is mounted in portrait 1878 mode or even if it's mounted landscape but rotated by 180degree, 1879 we need to rotate our content of the display relative to the 1880 framebuffer, so that user can read the messages which are 1881 printed out. 1882 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1883 initialized with a given rotation from "vl_rot" out of 1884 "vidinfo_t" which is provided by the board specific code. 1885 The value for vl_rot is coded as following (matching to 1886 fbcon=rotate:<n> linux-kernel commandline): 1887 0 = no rotation respectively 0 degree 1888 1 = 90 degree rotation 1889 2 = 180 degree rotation 1890 3 = 270 degree rotation 1891 1892 If CONFIG_LCD_ROTATION is not defined, the console will be 1893 initialized with 0degree rotation. 1894 1895 CONFIG_LCD_BMP_RLE8 1896 1897 Support drawing of RLE8-compressed bitmaps on the LCD. 1898 1899 CONFIG_I2C_EDID 1900 1901 Enables an 'i2c edid' command which can read EDID 1902 information over I2C from an attached LCD display. 1903 1904- Splash Screen Support: CONFIG_SPLASH_SCREEN 1905 1906 If this option is set, the environment is checked for 1907 a variable "splashimage". If found, the usual display 1908 of logo, copyright and system information on the LCD 1909 is suppressed and the BMP image at the address 1910 specified in "splashimage" is loaded instead. The 1911 console is redirected to the "nulldev", too. This 1912 allows for a "silent" boot where a splash screen is 1913 loaded very quickly after power-on. 1914 1915 CONFIG_SPLASHIMAGE_GUARD 1916 1917 If this option is set, then U-Boot will prevent the environment 1918 variable "splashimage" from being set to a problematic address 1919 (see doc/README.displaying-bmps). 1920 This option is useful for targets where, due to alignment 1921 restrictions, an improperly aligned BMP image will cause a data 1922 abort. If you think you will not have problems with unaligned 1923 accesses (for example because your toolchain prevents them) 1924 there is no need to set this option. 1925 1926 CONFIG_SPLASH_SCREEN_ALIGN 1927 1928 If this option is set the splash image can be freely positioned 1929 on the screen. Environment variable "splashpos" specifies the 1930 position as "x,y". If a positive number is given it is used as 1931 number of pixel from left/top. If a negative number is given it 1932 is used as number of pixel from right/bottom. You can also 1933 specify 'm' for centering the image. 1934 1935 Example: 1936 setenv splashpos m,m 1937 => image at center of screen 1938 1939 setenv splashpos 30,20 1940 => image at x = 30 and y = 20 1941 1942 setenv splashpos -10,m 1943 => vertically centered image 1944 at x = dspWidth - bmpWidth - 9 1945 1946- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1947 1948 If this option is set, additionally to standard BMP 1949 images, gzipped BMP images can be displayed via the 1950 splashscreen support or the bmp command. 1951 1952- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1953 1954 If this option is set, 8-bit RLE compressed BMP images 1955 can be displayed via the splashscreen support or the 1956 bmp command. 1957 1958- Do compressing for memory range: 1959 CONFIG_CMD_ZIP 1960 1961 If this option is set, it would use zlib deflate method 1962 to compress the specified memory at its best effort. 1963 1964- Compression support: 1965 CONFIG_GZIP 1966 1967 Enabled by default to support gzip compressed images. 1968 1969 CONFIG_BZIP2 1970 1971 If this option is set, support for bzip2 compressed 1972 images is included. If not, only uncompressed and gzip 1973 compressed images are supported. 1974 1975 NOTE: the bzip2 algorithm requires a lot of RAM, so 1976 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1977 be at least 4MB. 1978 1979 CONFIG_LZMA 1980 1981 If this option is set, support for lzma compressed 1982 images is included. 1983 1984 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1985 requires an amount of dynamic memory that is given by the 1986 formula: 1987 1988 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1989 1990 Where lc and lp stand for, respectively, Literal context bits 1991 and Literal pos bits. 1992 1993 This value is upper-bounded by 14MB in the worst case. Anyway, 1994 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1995 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1996 a very small buffer. 1997 1998 Use the lzmainfo tool to determinate the lc and lp values and 1999 then calculate the amount of needed dynamic memory (ensuring 2000 the appropriate CONFIG_SYS_MALLOC_LEN value). 2001 2002 CONFIG_LZO 2003 2004 If this option is set, support for LZO compressed images 2005 is included. 2006 2007- MII/PHY support: 2008 CONFIG_PHY_ADDR 2009 2010 The address of PHY on MII bus. 2011 2012 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2013 2014 The clock frequency of the MII bus 2015 2016 CONFIG_PHY_GIGE 2017 2018 If this option is set, support for speed/duplex 2019 detection of gigabit PHY is included. 2020 2021 CONFIG_PHY_RESET_DELAY 2022 2023 Some PHY like Intel LXT971A need extra delay after 2024 reset before any MII register access is possible. 2025 For such PHY, set this option to the usec delay 2026 required. (minimum 300usec for LXT971A) 2027 2028 CONFIG_PHY_CMD_DELAY (ppc4xx) 2029 2030 Some PHY like Intel LXT971A need extra delay after 2031 command issued before MII status register can be read 2032 2033- IP address: 2034 CONFIG_IPADDR 2035 2036 Define a default value for the IP address to use for 2037 the default Ethernet interface, in case this is not 2038 determined through e.g. bootp. 2039 (Environment variable "ipaddr") 2040 2041- Server IP address: 2042 CONFIG_SERVERIP 2043 2044 Defines a default value for the IP address of a TFTP 2045 server to contact when using the "tftboot" command. 2046 (Environment variable "serverip") 2047 2048 CONFIG_KEEP_SERVERADDR 2049 2050 Keeps the server's MAC address, in the env 'serveraddr' 2051 for passing to bootargs (like Linux's netconsole option) 2052 2053- Gateway IP address: 2054 CONFIG_GATEWAYIP 2055 2056 Defines a default value for the IP address of the 2057 default router where packets to other networks are 2058 sent to. 2059 (Environment variable "gatewayip") 2060 2061- Subnet mask: 2062 CONFIG_NETMASK 2063 2064 Defines a default value for the subnet mask (or 2065 routing prefix) which is used to determine if an IP 2066 address belongs to the local subnet or needs to be 2067 forwarded through a router. 2068 (Environment variable "netmask") 2069 2070- Multicast TFTP Mode: 2071 CONFIG_MCAST_TFTP 2072 2073 Defines whether you want to support multicast TFTP as per 2074 rfc-2090; for example to work with atftp. Lets lots of targets 2075 tftp down the same boot image concurrently. Note: the Ethernet 2076 driver in use must provide a function: mcast() to join/leave a 2077 multicast group. 2078 2079- BOOTP Recovery Mode: 2080 CONFIG_BOOTP_RANDOM_DELAY 2081 2082 If you have many targets in a network that try to 2083 boot using BOOTP, you may want to avoid that all 2084 systems send out BOOTP requests at precisely the same 2085 moment (which would happen for instance at recovery 2086 from a power failure, when all systems will try to 2087 boot, thus flooding the BOOTP server. Defining 2088 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2089 inserted before sending out BOOTP requests. The 2090 following delays are inserted then: 2091 2092 1st BOOTP request: delay 0 ... 1 sec 2093 2nd BOOTP request: delay 0 ... 2 sec 2094 3rd BOOTP request: delay 0 ... 4 sec 2095 4th and following 2096 BOOTP requests: delay 0 ... 8 sec 2097 2098 CONFIG_BOOTP_ID_CACHE_SIZE 2099 2100 BOOTP packets are uniquely identified using a 32-bit ID. The 2101 server will copy the ID from client requests to responses and 2102 U-Boot will use this to determine if it is the destination of 2103 an incoming response. Some servers will check that addresses 2104 aren't in use before handing them out (usually using an ARP 2105 ping) and therefore take up to a few hundred milliseconds to 2106 respond. Network congestion may also influence the time it 2107 takes for a response to make it back to the client. If that 2108 time is too long, U-Boot will retransmit requests. In order 2109 to allow earlier responses to still be accepted after these 2110 retransmissions, U-Boot's BOOTP client keeps a small cache of 2111 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2112 cache. The default is to keep IDs for up to four outstanding 2113 requests. Increasing this will allow U-Boot to accept offers 2114 from a BOOTP client in networks with unusually high latency. 2115 2116- DHCP Advanced Options: 2117 You can fine tune the DHCP functionality by defining 2118 CONFIG_BOOTP_* symbols: 2119 2120 CONFIG_BOOTP_SUBNETMASK 2121 CONFIG_BOOTP_GATEWAY 2122 CONFIG_BOOTP_HOSTNAME 2123 CONFIG_BOOTP_NISDOMAIN 2124 CONFIG_BOOTP_BOOTPATH 2125 CONFIG_BOOTP_BOOTFILESIZE 2126 CONFIG_BOOTP_DNS 2127 CONFIG_BOOTP_DNS2 2128 CONFIG_BOOTP_SEND_HOSTNAME 2129 CONFIG_BOOTP_NTPSERVER 2130 CONFIG_BOOTP_TIMEOFFSET 2131 CONFIG_BOOTP_VENDOREX 2132 CONFIG_BOOTP_MAY_FAIL 2133 2134 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2135 environment variable, not the BOOTP server. 2136 2137 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2138 after the configured retry count, the call will fail 2139 instead of starting over. This can be used to fail over 2140 to Link-local IP address configuration if the DHCP server 2141 is not available. 2142 2143 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2144 serverip from a DHCP server, it is possible that more 2145 than one DNS serverip is offered to the client. 2146 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2147 serverip will be stored in the additional environment 2148 variable "dnsip2". The first DNS serverip is always 2149 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2150 is defined. 2151 2152 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2153 to do a dynamic update of a DNS server. To do this, they 2154 need the hostname of the DHCP requester. 2155 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2156 of the "hostname" environment variable is passed as 2157 option 12 to the DHCP server. 2158 2159 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2160 2161 A 32bit value in microseconds for a delay between 2162 receiving a "DHCP Offer" and sending the "DHCP Request". 2163 This fixes a problem with certain DHCP servers that don't 2164 respond 100% of the time to a "DHCP request". E.g. On an 2165 AT91RM9200 processor running at 180MHz, this delay needed 2166 to be *at least* 15,000 usec before a Windows Server 2003 2167 DHCP server would reply 100% of the time. I recommend at 2168 least 50,000 usec to be safe. The alternative is to hope 2169 that one of the retries will be successful but note that 2170 the DHCP timeout and retry process takes a longer than 2171 this delay. 2172 2173 - Link-local IP address negotiation: 2174 Negotiate with other link-local clients on the local network 2175 for an address that doesn't require explicit configuration. 2176 This is especially useful if a DHCP server cannot be guaranteed 2177 to exist in all environments that the device must operate. 2178 2179 See doc/README.link-local for more information. 2180 2181 - CDP Options: 2182 CONFIG_CDP_DEVICE_ID 2183 2184 The device id used in CDP trigger frames. 2185 2186 CONFIG_CDP_DEVICE_ID_PREFIX 2187 2188 A two character string which is prefixed to the MAC address 2189 of the device. 2190 2191 CONFIG_CDP_PORT_ID 2192 2193 A printf format string which contains the ascii name of 2194 the port. Normally is set to "eth%d" which sets 2195 eth0 for the first Ethernet, eth1 for the second etc. 2196 2197 CONFIG_CDP_CAPABILITIES 2198 2199 A 32bit integer which indicates the device capabilities; 2200 0x00000010 for a normal host which does not forwards. 2201 2202 CONFIG_CDP_VERSION 2203 2204 An ascii string containing the version of the software. 2205 2206 CONFIG_CDP_PLATFORM 2207 2208 An ascii string containing the name of the platform. 2209 2210 CONFIG_CDP_TRIGGER 2211 2212 A 32bit integer sent on the trigger. 2213 2214 CONFIG_CDP_POWER_CONSUMPTION 2215 2216 A 16bit integer containing the power consumption of the 2217 device in .1 of milliwatts. 2218 2219 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2220 2221 A byte containing the id of the VLAN. 2222 2223- Status LED: CONFIG_STATUS_LED 2224 2225 Several configurations allow to display the current 2226 status using a LED. For instance, the LED will blink 2227 fast while running U-Boot code, stop blinking as 2228 soon as a reply to a BOOTP request was received, and 2229 start blinking slow once the Linux kernel is running 2230 (supported by a status LED driver in the Linux 2231 kernel). Defining CONFIG_STATUS_LED enables this 2232 feature in U-Boot. 2233 2234 Additional options: 2235 2236 CONFIG_GPIO_LED 2237 The status LED can be connected to a GPIO pin. 2238 In such cases, the gpio_led driver can be used as a 2239 status LED backend implementation. Define CONFIG_GPIO_LED 2240 to include the gpio_led driver in the U-Boot binary. 2241 2242 CONFIG_GPIO_LED_INVERTED_TABLE 2243 Some GPIO connected LEDs may have inverted polarity in which 2244 case the GPIO high value corresponds to LED off state and 2245 GPIO low value corresponds to LED on state. 2246 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2247 with a list of GPIO LEDs that have inverted polarity. 2248 2249- CAN Support: CONFIG_CAN_DRIVER 2250 2251 Defining CONFIG_CAN_DRIVER enables CAN driver support 2252 on those systems that support this (optional) 2253 feature, like the TQM8xxL modules. 2254 2255- I2C Support: CONFIG_SYS_I2C 2256 2257 This enable the NEW i2c subsystem, and will allow you to use 2258 i2c commands at the u-boot command line (as long as you set 2259 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2260 based realtime clock chips or other i2c devices. See 2261 common/cmd_i2c.c for a description of the command line 2262 interface. 2263 2264 ported i2c driver to the new framework: 2265 - drivers/i2c/soft_i2c.c: 2266 - activate first bus with CONFIG_SYS_I2C_SOFT define 2267 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2268 for defining speed and slave address 2269 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2270 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2271 for defining speed and slave address 2272 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2273 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2274 for defining speed and slave address 2275 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2276 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2277 for defining speed and slave address 2278 2279 - drivers/i2c/fsl_i2c.c: 2280 - activate i2c driver with CONFIG_SYS_I2C_FSL 2281 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2282 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2283 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2284 bus. 2285 - If your board supports a second fsl i2c bus, define 2286 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2287 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2288 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2289 second bus. 2290 2291 - drivers/i2c/tegra_i2c.c: 2292 - activate this driver with CONFIG_SYS_I2C_TEGRA 2293 - This driver adds 4 i2c buses with a fix speed from 2294 100000 and the slave addr 0! 2295 2296 - drivers/i2c/ppc4xx_i2c.c 2297 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2298 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2299 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2300 2301 - drivers/i2c/i2c_mxc.c 2302 - activate this driver with CONFIG_SYS_I2C_MXC 2303 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2304 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2305 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2306 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2307 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2308 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2309 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2310 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2311 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2312 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2313 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2314 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2315 If those defines are not set, default value is 100000 2316 for speed, and 0 for slave. 2317 2318 - drivers/i2c/rcar_i2c.c: 2319 - activate this driver with CONFIG_SYS_I2C_RCAR 2320 - This driver adds 4 i2c buses 2321 2322 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2323 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2324 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2325 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2326 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2327 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2328 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2329 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2330 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2331 2332 - drivers/i2c/sh_i2c.c: 2333 - activate this driver with CONFIG_SYS_I2C_SH 2334 - This driver adds from 2 to 5 i2c buses 2335 2336 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2337 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2338 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2339 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2340 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2341 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2342 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2343 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2344 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2345 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2346 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2347 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2348 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2349 2350 - drivers/i2c/omap24xx_i2c.c 2351 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2352 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2353 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2354 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2355 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2356 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2357 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2358 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2359 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2360 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2361 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2362 2363 - drivers/i2c/zynq_i2c.c 2364 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2365 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2366 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2367 2368 - drivers/i2c/s3c24x0_i2c.c: 2369 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2370 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2371 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2372 with a fix speed from 100000 and the slave addr 0! 2373 2374 - drivers/i2c/ihs_i2c.c 2375 - activate this driver with CONFIG_SYS_I2C_IHS 2376 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2377 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2378 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2379 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2380 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2381 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2382 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2383 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2384 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2385 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2386 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2387 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2388 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2389 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2390 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2391 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2392 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2393 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2394 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2395 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2396 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2397 2398 additional defines: 2399 2400 CONFIG_SYS_NUM_I2C_BUSES 2401 Hold the number of i2c buses you want to use. If you 2402 don't use/have i2c muxes on your i2c bus, this 2403 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2404 omit this define. 2405 2406 CONFIG_SYS_I2C_DIRECT_BUS 2407 define this, if you don't use i2c muxes on your hardware. 2408 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2409 omit this define. 2410 2411 CONFIG_SYS_I2C_MAX_HOPS 2412 define how many muxes are maximal consecutively connected 2413 on one i2c bus. If you not use i2c muxes, omit this 2414 define. 2415 2416 CONFIG_SYS_I2C_BUSES 2417 hold a list of buses you want to use, only used if 2418 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2419 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2420 CONFIG_SYS_NUM_I2C_BUSES = 9: 2421 2422 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2423 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2424 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2425 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2426 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2427 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2428 {1, {I2C_NULL_HOP}}, \ 2429 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2430 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2431 } 2432 2433 which defines 2434 bus 0 on adapter 0 without a mux 2435 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2436 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2437 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2438 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2439 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2440 bus 6 on adapter 1 without a mux 2441 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2442 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2443 2444 If you do not have i2c muxes on your board, omit this define. 2445 2446- Legacy I2C Support: CONFIG_HARD_I2C 2447 2448 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2449 provides the following compelling advantages: 2450 2451 - more than one i2c adapter is usable 2452 - approved multibus support 2453 - better i2c mux support 2454 2455 ** Please consider updating your I2C driver now. ** 2456 2457 These enable legacy I2C serial bus commands. Defining 2458 CONFIG_HARD_I2C will include the appropriate I2C driver 2459 for the selected CPU. 2460 2461 This will allow you to use i2c commands at the u-boot 2462 command line (as long as you set CONFIG_CMD_I2C in 2463 CONFIG_COMMANDS) and communicate with i2c based realtime 2464 clock chips. See common/cmd_i2c.c for a description of the 2465 command line interface. 2466 2467 CONFIG_HARD_I2C selects a hardware I2C controller. 2468 2469 There are several other quantities that must also be 2470 defined when you define CONFIG_HARD_I2C. 2471 2472 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2473 to be the frequency (in Hz) at which you wish your i2c bus 2474 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2475 the CPU's i2c node address). 2476 2477 Now, the u-boot i2c code for the mpc8xx 2478 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2479 and so its address should therefore be cleared to 0 (See, 2480 eg, MPC823e User's Manual p.16-473). So, set 2481 CONFIG_SYS_I2C_SLAVE to 0. 2482 2483 CONFIG_SYS_I2C_INIT_MPC5XXX 2484 2485 When a board is reset during an i2c bus transfer 2486 chips might think that the current transfer is still 2487 in progress. Reset the slave devices by sending start 2488 commands until the slave device responds. 2489 2490 That's all that's required for CONFIG_HARD_I2C. 2491 2492 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2493 then the following macros need to be defined (examples are 2494 from include/configs/lwmon.h): 2495 2496 I2C_INIT 2497 2498 (Optional). Any commands necessary to enable the I2C 2499 controller or configure ports. 2500 2501 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2502 2503 I2C_PORT 2504 2505 (Only for MPC8260 CPU). The I/O port to use (the code 2506 assumes both bits are on the same port). Valid values 2507 are 0..3 for ports A..D. 2508 2509 I2C_ACTIVE 2510 2511 The code necessary to make the I2C data line active 2512 (driven). If the data line is open collector, this 2513 define can be null. 2514 2515 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2516 2517 I2C_TRISTATE 2518 2519 The code necessary to make the I2C data line tri-stated 2520 (inactive). If the data line is open collector, this 2521 define can be null. 2522 2523 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2524 2525 I2C_READ 2526 2527 Code that returns true if the I2C data line is high, 2528 false if it is low. 2529 2530 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2531 2532 I2C_SDA(bit) 2533 2534 If <bit> is true, sets the I2C data line high. If it 2535 is false, it clears it (low). 2536 2537 eg: #define I2C_SDA(bit) \ 2538 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2539 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2540 2541 I2C_SCL(bit) 2542 2543 If <bit> is true, sets the I2C clock line high. If it 2544 is false, it clears it (low). 2545 2546 eg: #define I2C_SCL(bit) \ 2547 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2548 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2549 2550 I2C_DELAY 2551 2552 This delay is invoked four times per clock cycle so this 2553 controls the rate of data transfer. The data rate thus 2554 is 1 / (I2C_DELAY * 4). Often defined to be something 2555 like: 2556 2557 #define I2C_DELAY udelay(2) 2558 2559 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2560 2561 If your arch supports the generic GPIO framework (asm/gpio.h), 2562 then you may alternatively define the two GPIOs that are to be 2563 used as SCL / SDA. Any of the previous I2C_xxx macros will 2564 have GPIO-based defaults assigned to them as appropriate. 2565 2566 You should define these to the GPIO value as given directly to 2567 the generic GPIO functions. 2568 2569 CONFIG_SYS_I2C_INIT_BOARD 2570 2571 When a board is reset during an i2c bus transfer 2572 chips might think that the current transfer is still 2573 in progress. On some boards it is possible to access 2574 the i2c SCLK line directly, either by using the 2575 processor pin as a GPIO or by having a second pin 2576 connected to the bus. If this option is defined a 2577 custom i2c_init_board() routine in boards/xxx/board.c 2578 is run early in the boot sequence. 2579 2580 CONFIG_SYS_I2C_BOARD_LATE_INIT 2581 2582 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2583 defined a custom i2c_board_late_init() routine in 2584 boards/xxx/board.c is run AFTER the operations in i2c_init() 2585 is completed. This callpoint can be used to unreset i2c bus 2586 using CPU i2c controller register accesses for CPUs whose i2c 2587 controller provide such a method. It is called at the end of 2588 i2c_init() to allow i2c_init operations to setup the i2c bus 2589 controller on the CPU (e.g. setting bus speed & slave address). 2590 2591 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2592 2593 This option enables configuration of bi_iic_fast[] flags 2594 in u-boot bd_info structure based on u-boot environment 2595 variable "i2cfast". (see also i2cfast) 2596 2597 CONFIG_I2C_MULTI_BUS 2598 2599 This option allows the use of multiple I2C buses, each of which 2600 must have a controller. At any point in time, only one bus is 2601 active. To switch to a different bus, use the 'i2c dev' command. 2602 Note that bus numbering is zero-based. 2603 2604 CONFIG_SYS_I2C_NOPROBES 2605 2606 This option specifies a list of I2C devices that will be skipped 2607 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2608 is set, specify a list of bus-device pairs. Otherwise, specify 2609 a 1D array of device addresses 2610 2611 e.g. 2612 #undef CONFIG_I2C_MULTI_BUS 2613 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2614 2615 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2616 2617 #define CONFIG_I2C_MULTI_BUS 2618 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2619 2620 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2621 2622 CONFIG_SYS_SPD_BUS_NUM 2623 2624 If defined, then this indicates the I2C bus number for DDR SPD. 2625 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2626 2627 CONFIG_SYS_RTC_BUS_NUM 2628 2629 If defined, then this indicates the I2C bus number for the RTC. 2630 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2631 2632 CONFIG_SYS_DTT_BUS_NUM 2633 2634 If defined, then this indicates the I2C bus number for the DTT. 2635 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2636 2637 CONFIG_SYS_I2C_DTT_ADDR: 2638 2639 If defined, specifies the I2C address of the DTT device. 2640 If not defined, then U-Boot uses predefined value for 2641 specified DTT device. 2642 2643 CONFIG_SOFT_I2C_READ_REPEATED_START 2644 2645 defining this will force the i2c_read() function in 2646 the soft_i2c driver to perform an I2C repeated start 2647 between writing the address pointer and reading the 2648 data. If this define is omitted the default behaviour 2649 of doing a stop-start sequence will be used. Most I2C 2650 devices can use either method, but some require one or 2651 the other. 2652 2653- SPI Support: CONFIG_SPI 2654 2655 Enables SPI driver (so far only tested with 2656 SPI EEPROM, also an instance works with Crystal A/D and 2657 D/As on the SACSng board) 2658 2659 CONFIG_SH_SPI 2660 2661 Enables the driver for SPI controller on SuperH. Currently 2662 only SH7757 is supported. 2663 2664 CONFIG_SOFT_SPI 2665 2666 Enables a software (bit-bang) SPI driver rather than 2667 using hardware support. This is a general purpose 2668 driver that only requires three general I/O port pins 2669 (two outputs, one input) to function. If this is 2670 defined, the board configuration must define several 2671 SPI configuration items (port pins to use, etc). For 2672 an example, see include/configs/sacsng.h. 2673 2674 CONFIG_HARD_SPI 2675 2676 Enables a hardware SPI driver for general-purpose reads 2677 and writes. As with CONFIG_SOFT_SPI, the board configuration 2678 must define a list of chip-select function pointers. 2679 Currently supported on some MPC8xxx processors. For an 2680 example, see include/configs/mpc8349emds.h. 2681 2682 CONFIG_MXC_SPI 2683 2684 Enables the driver for the SPI controllers on i.MX and MXC 2685 SoCs. Currently i.MX31/35/51 are supported. 2686 2687 CONFIG_SYS_SPI_MXC_WAIT 2688 Timeout for waiting until spi transfer completed. 2689 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2690 2691- FPGA Support: CONFIG_FPGA 2692 2693 Enables FPGA subsystem. 2694 2695 CONFIG_FPGA_<vendor> 2696 2697 Enables support for specific chip vendors. 2698 (ALTERA, XILINX) 2699 2700 CONFIG_FPGA_<family> 2701 2702 Enables support for FPGA family. 2703 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2704 2705 CONFIG_FPGA_COUNT 2706 2707 Specify the number of FPGA devices to support. 2708 2709 CONFIG_CMD_FPGA_LOADMK 2710 2711 Enable support for fpga loadmk command 2712 2713 CONFIG_CMD_FPGA_LOADP 2714 2715 Enable support for fpga loadp command - load partial bitstream 2716 2717 CONFIG_CMD_FPGA_LOADBP 2718 2719 Enable support for fpga loadbp command - load partial bitstream 2720 (Xilinx only) 2721 2722 CONFIG_SYS_FPGA_PROG_FEEDBACK 2723 2724 Enable printing of hash marks during FPGA configuration. 2725 2726 CONFIG_SYS_FPGA_CHECK_BUSY 2727 2728 Enable checks on FPGA configuration interface busy 2729 status by the configuration function. This option 2730 will require a board or device specific function to 2731 be written. 2732 2733 CONFIG_FPGA_DELAY 2734 2735 If defined, a function that provides delays in the FPGA 2736 configuration driver. 2737 2738 CONFIG_SYS_FPGA_CHECK_CTRLC 2739 Allow Control-C to interrupt FPGA configuration 2740 2741 CONFIG_SYS_FPGA_CHECK_ERROR 2742 2743 Check for configuration errors during FPGA bitfile 2744 loading. For example, abort during Virtex II 2745 configuration if the INIT_B line goes low (which 2746 indicated a CRC error). 2747 2748 CONFIG_SYS_FPGA_WAIT_INIT 2749 2750 Maximum time to wait for the INIT_B line to de-assert 2751 after PROB_B has been de-asserted during a Virtex II 2752 FPGA configuration sequence. The default time is 500 2753 ms. 2754 2755 CONFIG_SYS_FPGA_WAIT_BUSY 2756 2757 Maximum time to wait for BUSY to de-assert during 2758 Virtex II FPGA configuration. The default is 5 ms. 2759 2760 CONFIG_SYS_FPGA_WAIT_CONFIG 2761 2762 Time to wait after FPGA configuration. The default is 2763 200 ms. 2764 2765- Configuration Management: 2766 CONFIG_BUILD_TARGET 2767 2768 Some SoCs need special image types (e.g. U-Boot binary 2769 with a special header) as build targets. By defining 2770 CONFIG_BUILD_TARGET in the SoC / board header, this 2771 special image will be automatically built upon calling 2772 make / MAKEALL. 2773 2774 CONFIG_IDENT_STRING 2775 2776 If defined, this string will be added to the U-Boot 2777 version information (U_BOOT_VERSION) 2778 2779- Vendor Parameter Protection: 2780 2781 U-Boot considers the values of the environment 2782 variables "serial#" (Board Serial Number) and 2783 "ethaddr" (Ethernet Address) to be parameters that 2784 are set once by the board vendor / manufacturer, and 2785 protects these variables from casual modification by 2786 the user. Once set, these variables are read-only, 2787 and write or delete attempts are rejected. You can 2788 change this behaviour: 2789 2790 If CONFIG_ENV_OVERWRITE is #defined in your config 2791 file, the write protection for vendor parameters is 2792 completely disabled. Anybody can change or delete 2793 these parameters. 2794 2795 Alternatively, if you define _both_ an ethaddr in the 2796 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2797 Ethernet address is installed in the environment, 2798 which can be changed exactly ONCE by the user. [The 2799 serial# is unaffected by this, i. e. it remains 2800 read-only.] 2801 2802 The same can be accomplished in a more flexible way 2803 for any variable by configuring the type of access 2804 to allow for those variables in the ".flags" variable 2805 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2806 2807- Protected RAM: 2808 CONFIG_PRAM 2809 2810 Define this variable to enable the reservation of 2811 "protected RAM", i. e. RAM which is not overwritten 2812 by U-Boot. Define CONFIG_PRAM to hold the number of 2813 kB you want to reserve for pRAM. You can overwrite 2814 this default value by defining an environment 2815 variable "pram" to the number of kB you want to 2816 reserve. Note that the board info structure will 2817 still show the full amount of RAM. If pRAM is 2818 reserved, a new environment variable "mem" will 2819 automatically be defined to hold the amount of 2820 remaining RAM in a form that can be passed as boot 2821 argument to Linux, for instance like that: 2822 2823 setenv bootargs ... mem=\${mem} 2824 saveenv 2825 2826 This way you can tell Linux not to use this memory, 2827 either, which results in a memory region that will 2828 not be affected by reboots. 2829 2830 *WARNING* If your board configuration uses automatic 2831 detection of the RAM size, you must make sure that 2832 this memory test is non-destructive. So far, the 2833 following board configurations are known to be 2834 "pRAM-clean": 2835 2836 IVMS8, IVML24, SPD8xx, TQM8xxL, 2837 HERMES, IP860, RPXlite, LWMON, 2838 FLAGADM, TQM8260 2839 2840- Access to physical memory region (> 4GB) 2841 Some basic support is provided for operations on memory not 2842 normally accessible to U-Boot - e.g. some architectures 2843 support access to more than 4GB of memory on 32-bit 2844 machines using physical address extension or similar. 2845 Define CONFIG_PHYSMEM to access this basic support, which 2846 currently only supports clearing the memory. 2847 2848- Error Recovery: 2849 CONFIG_PANIC_HANG 2850 2851 Define this variable to stop the system in case of a 2852 fatal error, so that you have to reset it manually. 2853 This is probably NOT a good idea for an embedded 2854 system where you want the system to reboot 2855 automatically as fast as possible, but it may be 2856 useful during development since you can try to debug 2857 the conditions that lead to the situation. 2858 2859 CONFIG_NET_RETRY_COUNT 2860 2861 This variable defines the number of retries for 2862 network operations like ARP, RARP, TFTP, or BOOTP 2863 before giving up the operation. If not defined, a 2864 default value of 5 is used. 2865 2866 CONFIG_ARP_TIMEOUT 2867 2868 Timeout waiting for an ARP reply in milliseconds. 2869 2870 CONFIG_NFS_TIMEOUT 2871 2872 Timeout in milliseconds used in NFS protocol. 2873 If you encounter "ERROR: Cannot umount" in nfs command, 2874 try longer timeout such as 2875 #define CONFIG_NFS_TIMEOUT 10000UL 2876 2877- Command Interpreter: 2878 CONFIG_AUTO_COMPLETE 2879 2880 Enable auto completion of commands using TAB. 2881 2882 CONFIG_SYS_PROMPT_HUSH_PS2 2883 2884 This defines the secondary prompt string, which is 2885 printed when the command interpreter needs more input 2886 to complete a command. Usually "> ". 2887 2888 Note: 2889 2890 In the current implementation, the local variables 2891 space and global environment variables space are 2892 separated. Local variables are those you define by 2893 simply typing `name=value'. To access a local 2894 variable later on, you have write `$name' or 2895 `${name}'; to execute the contents of a variable 2896 directly type `$name' at the command prompt. 2897 2898 Global environment variables are those you use 2899 setenv/printenv to work with. To run a command stored 2900 in such a variable, you need to use the run command, 2901 and you must not use the '$' sign to access them. 2902 2903 To store commands and special characters in a 2904 variable, please use double quotation marks 2905 surrounding the whole text of the variable, instead 2906 of the backslashes before semicolons and special 2907 symbols. 2908 2909- Command Line Editing and History: 2910 CONFIG_CMDLINE_EDITING 2911 2912 Enable editing and History functions for interactive 2913 command line input operations 2914 2915- Command Line PS1/PS2 support: 2916 CONFIG_CMDLINE_PS_SUPPORT 2917 2918 Enable support for changing the command prompt string 2919 at run-time. Only static string is supported so far. 2920 The string is obtained from environment variables PS1 2921 and PS2. 2922 2923- Default Environment: 2924 CONFIG_EXTRA_ENV_SETTINGS 2925 2926 Define this to contain any number of null terminated 2927 strings (variable = value pairs) that will be part of 2928 the default environment compiled into the boot image. 2929 2930 For example, place something like this in your 2931 board's config file: 2932 2933 #define CONFIG_EXTRA_ENV_SETTINGS \ 2934 "myvar1=value1\0" \ 2935 "myvar2=value2\0" 2936 2937 Warning: This method is based on knowledge about the 2938 internal format how the environment is stored by the 2939 U-Boot code. This is NOT an official, exported 2940 interface! Although it is unlikely that this format 2941 will change soon, there is no guarantee either. 2942 You better know what you are doing here. 2943 2944 Note: overly (ab)use of the default environment is 2945 discouraged. Make sure to check other ways to preset 2946 the environment like the "source" command or the 2947 boot command first. 2948 2949 CONFIG_ENV_VARS_UBOOT_CONFIG 2950 2951 Define this in order to add variables describing the 2952 U-Boot build configuration to the default environment. 2953 These will be named arch, cpu, board, vendor, and soc. 2954 2955 Enabling this option will cause the following to be defined: 2956 2957 - CONFIG_SYS_ARCH 2958 - CONFIG_SYS_CPU 2959 - CONFIG_SYS_BOARD 2960 - CONFIG_SYS_VENDOR 2961 - CONFIG_SYS_SOC 2962 2963 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2964 2965 Define this in order to add variables describing certain 2966 run-time determined information about the hardware to the 2967 environment. These will be named board_name, board_rev. 2968 2969 CONFIG_DELAY_ENVIRONMENT 2970 2971 Normally the environment is loaded when the board is 2972 initialised so that it is available to U-Boot. This inhibits 2973 that so that the environment is not available until 2974 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2975 this is instead controlled by the value of 2976 /config/load-environment. 2977 2978- Parallel Flash support: 2979 CONFIG_SYS_NO_FLASH 2980 2981 Traditionally U-Boot was run on systems with parallel NOR 2982 flash. This option is used to disable support for parallel NOR 2983 flash. This option should be defined if the board does not have 2984 parallel flash. 2985 2986 If this option is not defined one of the generic flash drivers 2987 (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be 2988 selected or the board must provide an implementation of the 2989 flash API (see include/flash.h). 2990 2991- DataFlash Support: 2992 CONFIG_HAS_DATAFLASH 2993 2994 Defining this option enables DataFlash features and 2995 allows to read/write in Dataflash via the standard 2996 commands cp, md... 2997 2998- Serial Flash support 2999 CONFIG_CMD_SF 3000 3001 Defining this option enables SPI flash commands 3002 'sf probe/read/write/erase/update'. 3003 3004 Usage requires an initial 'probe' to define the serial 3005 flash parameters, followed by read/write/erase/update 3006 commands. 3007 3008 The following defaults may be provided by the platform 3009 to handle the common case when only a single serial 3010 flash is present on the system. 3011 3012 CONFIG_SF_DEFAULT_BUS Bus identifier 3013 CONFIG_SF_DEFAULT_CS Chip-select 3014 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3015 CONFIG_SF_DEFAULT_SPEED in Hz 3016 3017 CONFIG_CMD_SF_TEST 3018 3019 Define this option to include a destructive SPI flash 3020 test ('sf test'). 3021 3022 CONFIG_SF_DUAL_FLASH Dual flash memories 3023 3024 Define this option to use dual flash support where two flash 3025 memories can be connected with a given cs line. 3026 Currently Xilinx Zynq qspi supports these type of connections. 3027 3028- SystemACE Support: 3029 CONFIG_SYSTEMACE 3030 3031 Adding this option adds support for Xilinx SystemACE 3032 chips attached via some sort of local bus. The address 3033 of the chip must also be defined in the 3034 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3035 3036 #define CONFIG_SYSTEMACE 3037 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3038 3039 When SystemACE support is added, the "ace" device type 3040 becomes available to the fat commands, i.e. fatls. 3041 3042- TFTP Fixed UDP Port: 3043 CONFIG_TFTP_PORT 3044 3045 If this is defined, the environment variable tftpsrcp 3046 is used to supply the TFTP UDP source port value. 3047 If tftpsrcp isn't defined, the normal pseudo-random port 3048 number generator is used. 3049 3050 Also, the environment variable tftpdstp is used to supply 3051 the TFTP UDP destination port value. If tftpdstp isn't 3052 defined, the normal port 69 is used. 3053 3054 The purpose for tftpsrcp is to allow a TFTP server to 3055 blindly start the TFTP transfer using the pre-configured 3056 target IP address and UDP port. This has the effect of 3057 "punching through" the (Windows XP) firewall, allowing 3058 the remainder of the TFTP transfer to proceed normally. 3059 A better solution is to properly configure the firewall, 3060 but sometimes that is not allowed. 3061 3062- Hashing support: 3063 CONFIG_CMD_HASH 3064 3065 This enables a generic 'hash' command which can produce 3066 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3067 3068 CONFIG_HASH_VERIFY 3069 3070 Enable the hash verify command (hash -v). This adds to code 3071 size a little. 3072 3073 CONFIG_SHA1 - This option enables support of hashing using SHA1 3074 algorithm. The hash is calculated in software. 3075 CONFIG_SHA256 - This option enables support of hashing using 3076 SHA256 algorithm. The hash is calculated in software. 3077 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3078 for SHA1/SHA256 hashing. 3079 This affects the 'hash' command and also the 3080 hash_lookup_algo() function. 3081 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3082 hardware-acceleration for SHA1/SHA256 progressive hashing. 3083 Data can be streamed in a block at a time and the hashing 3084 is performed in hardware. 3085 3086 Note: There is also a sha1sum command, which should perhaps 3087 be deprecated in favour of 'hash sha1'. 3088 3089- Freescale i.MX specific commands: 3090 CONFIG_CMD_HDMIDETECT 3091 This enables 'hdmidet' command which returns true if an 3092 HDMI monitor is detected. This command is i.MX 6 specific. 3093 3094 CONFIG_CMD_BMODE 3095 This enables the 'bmode' (bootmode) command for forcing 3096 a boot from specific media. 3097 3098 This is useful for forcing the ROM's usb downloader to 3099 activate upon a watchdog reset which is nice when iterating 3100 on U-Boot. Using the reset button or running bmode normal 3101 will set it back to normal. This command currently 3102 supports i.MX53 and i.MX6. 3103 3104- bootcount support: 3105 CONFIG_BOOTCOUNT_LIMIT 3106 3107 This enables the bootcounter support, see: 3108 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3109 3110 CONFIG_AT91SAM9XE 3111 enable special bootcounter support on at91sam9xe based boards. 3112 CONFIG_BLACKFIN 3113 enable special bootcounter support on blackfin based boards. 3114 CONFIG_SOC_DA8XX 3115 enable special bootcounter support on da850 based boards. 3116 CONFIG_BOOTCOUNT_RAM 3117 enable support for the bootcounter in RAM 3118 CONFIG_BOOTCOUNT_I2C 3119 enable support for the bootcounter on an i2c (like RTC) device. 3120 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3121 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3122 the bootcounter. 3123 CONFIG_BOOTCOUNT_ALEN = address len 3124 3125- Show boot progress: 3126 CONFIG_SHOW_BOOT_PROGRESS 3127 3128 Defining this option allows to add some board- 3129 specific code (calling a user-provided function 3130 "show_boot_progress(int)") that enables you to show 3131 the system's boot progress on some display (for 3132 example, some LED's) on your board. At the moment, 3133 the following checkpoints are implemented: 3134 3135 3136Legacy uImage format: 3137 3138 Arg Where When 3139 1 common/cmd_bootm.c before attempting to boot an image 3140 -1 common/cmd_bootm.c Image header has bad magic number 3141 2 common/cmd_bootm.c Image header has correct magic number 3142 -2 common/cmd_bootm.c Image header has bad checksum 3143 3 common/cmd_bootm.c Image header has correct checksum 3144 -3 common/cmd_bootm.c Image data has bad checksum 3145 4 common/cmd_bootm.c Image data has correct checksum 3146 -4 common/cmd_bootm.c Image is for unsupported architecture 3147 5 common/cmd_bootm.c Architecture check OK 3148 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3149 6 common/cmd_bootm.c Image Type check OK 3150 -6 common/cmd_bootm.c gunzip uncompression error 3151 -7 common/cmd_bootm.c Unimplemented compression type 3152 7 common/cmd_bootm.c Uncompression OK 3153 8 common/cmd_bootm.c No uncompress/copy overwrite error 3154 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3155 3156 9 common/image.c Start initial ramdisk verification 3157 -10 common/image.c Ramdisk header has bad magic number 3158 -11 common/image.c Ramdisk header has bad checksum 3159 10 common/image.c Ramdisk header is OK 3160 -12 common/image.c Ramdisk data has bad checksum 3161 11 common/image.c Ramdisk data has correct checksum 3162 12 common/image.c Ramdisk verification complete, start loading 3163 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3164 13 common/image.c Start multifile image verification 3165 14 common/image.c No initial ramdisk, no multifile, continue. 3166 3167 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3168 3169 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3170 -31 post/post.c POST test failed, detected by post_output_backlog() 3171 -32 post/post.c POST test failed, detected by post_run_single() 3172 3173 34 common/cmd_doc.c before loading a Image from a DOC device 3174 -35 common/cmd_doc.c Bad usage of "doc" command 3175 35 common/cmd_doc.c correct usage of "doc" command 3176 -36 common/cmd_doc.c No boot device 3177 36 common/cmd_doc.c correct boot device 3178 -37 common/cmd_doc.c Unknown Chip ID on boot device 3179 37 common/cmd_doc.c correct chip ID found, device available 3180 -38 common/cmd_doc.c Read Error on boot device 3181 38 common/cmd_doc.c reading Image header from DOC device OK 3182 -39 common/cmd_doc.c Image header has bad magic number 3183 39 common/cmd_doc.c Image header has correct magic number 3184 -40 common/cmd_doc.c Error reading Image from DOC device 3185 40 common/cmd_doc.c Image header has correct magic number 3186 41 common/cmd_ide.c before loading a Image from a IDE device 3187 -42 common/cmd_ide.c Bad usage of "ide" command 3188 42 common/cmd_ide.c correct usage of "ide" command 3189 -43 common/cmd_ide.c No boot device 3190 43 common/cmd_ide.c boot device found 3191 -44 common/cmd_ide.c Device not available 3192 44 common/cmd_ide.c Device available 3193 -45 common/cmd_ide.c wrong partition selected 3194 45 common/cmd_ide.c partition selected 3195 -46 common/cmd_ide.c Unknown partition table 3196 46 common/cmd_ide.c valid partition table found 3197 -47 common/cmd_ide.c Invalid partition type 3198 47 common/cmd_ide.c correct partition type 3199 -48 common/cmd_ide.c Error reading Image Header on boot device 3200 48 common/cmd_ide.c reading Image Header from IDE device OK 3201 -49 common/cmd_ide.c Image header has bad magic number 3202 49 common/cmd_ide.c Image header has correct magic number 3203 -50 common/cmd_ide.c Image header has bad checksum 3204 50 common/cmd_ide.c Image header has correct checksum 3205 -51 common/cmd_ide.c Error reading Image from IDE device 3206 51 common/cmd_ide.c reading Image from IDE device OK 3207 52 common/cmd_nand.c before loading a Image from a NAND device 3208 -53 common/cmd_nand.c Bad usage of "nand" command 3209 53 common/cmd_nand.c correct usage of "nand" command 3210 -54 common/cmd_nand.c No boot device 3211 54 common/cmd_nand.c boot device found 3212 -55 common/cmd_nand.c Unknown Chip ID on boot device 3213 55 common/cmd_nand.c correct chip ID found, device available 3214 -56 common/cmd_nand.c Error reading Image Header on boot device 3215 56 common/cmd_nand.c reading Image Header from NAND device OK 3216 -57 common/cmd_nand.c Image header has bad magic number 3217 57 common/cmd_nand.c Image header has correct magic number 3218 -58 common/cmd_nand.c Error reading Image from NAND device 3219 58 common/cmd_nand.c reading Image from NAND device OK 3220 3221 -60 common/env_common.c Environment has a bad CRC, using default 3222 3223 64 net/eth.c starting with Ethernet configuration. 3224 -64 net/eth.c no Ethernet found. 3225 65 net/eth.c Ethernet found. 3226 3227 -80 common/cmd_net.c usage wrong 3228 80 common/cmd_net.c before calling net_loop() 3229 -81 common/cmd_net.c some error in net_loop() occurred 3230 81 common/cmd_net.c net_loop() back without error 3231 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3232 82 common/cmd_net.c trying automatic boot 3233 83 common/cmd_net.c running "source" command 3234 -83 common/cmd_net.c some error in automatic boot or "source" command 3235 84 common/cmd_net.c end without errors 3236 3237FIT uImage format: 3238 3239 Arg Where When 3240 100 common/cmd_bootm.c Kernel FIT Image has correct format 3241 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3242 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3243 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3244 102 common/cmd_bootm.c Kernel unit name specified 3245 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3246 103 common/cmd_bootm.c Found configuration node 3247 104 common/cmd_bootm.c Got kernel subimage node offset 3248 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3249 105 common/cmd_bootm.c Kernel subimage hash verification OK 3250 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3251 106 common/cmd_bootm.c Architecture check OK 3252 -106 common/cmd_bootm.c Kernel subimage has wrong type 3253 107 common/cmd_bootm.c Kernel subimage type OK 3254 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3255 108 common/cmd_bootm.c Got kernel subimage data/size 3256 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3257 -109 common/cmd_bootm.c Can't get kernel subimage type 3258 -110 common/cmd_bootm.c Can't get kernel subimage comp 3259 -111 common/cmd_bootm.c Can't get kernel subimage os 3260 -112 common/cmd_bootm.c Can't get kernel subimage load address 3261 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3262 3263 120 common/image.c Start initial ramdisk verification 3264 -120 common/image.c Ramdisk FIT image has incorrect format 3265 121 common/image.c Ramdisk FIT image has correct format 3266 122 common/image.c No ramdisk subimage unit name, using configuration 3267 -122 common/image.c Can't get configuration for ramdisk subimage 3268 123 common/image.c Ramdisk unit name specified 3269 -124 common/image.c Can't get ramdisk subimage node offset 3270 125 common/image.c Got ramdisk subimage node offset 3271 -125 common/image.c Ramdisk subimage hash verification failed 3272 126 common/image.c Ramdisk subimage hash verification OK 3273 -126 common/image.c Ramdisk subimage for unsupported architecture 3274 127 common/image.c Architecture check OK 3275 -127 common/image.c Can't get ramdisk subimage data/size 3276 128 common/image.c Got ramdisk subimage data/size 3277 129 common/image.c Can't get ramdisk load address 3278 -129 common/image.c Got ramdisk load address 3279 3280 -130 common/cmd_doc.c Incorrect FIT image format 3281 131 common/cmd_doc.c FIT image format OK 3282 3283 -140 common/cmd_ide.c Incorrect FIT image format 3284 141 common/cmd_ide.c FIT image format OK 3285 3286 -150 common/cmd_nand.c Incorrect FIT image format 3287 151 common/cmd_nand.c FIT image format OK 3288 3289- legacy image format: 3290 CONFIG_IMAGE_FORMAT_LEGACY 3291 enables the legacy image format support in U-Boot. 3292 3293 Default: 3294 enabled if CONFIG_FIT_SIGNATURE is not defined. 3295 3296 CONFIG_DISABLE_IMAGE_LEGACY 3297 disable the legacy image format 3298 3299 This define is introduced, as the legacy image format is 3300 enabled per default for backward compatibility. 3301 3302- FIT image support: 3303 CONFIG_FIT_DISABLE_SHA256 3304 Supporting SHA256 hashes has quite an impact on binary size. 3305 For constrained systems sha256 hash support can be disabled 3306 with this option. 3307 3308 TODO(sjg@chromium.org): Adjust this option to be positive, 3309 and move it to Kconfig 3310 3311- Standalone program support: 3312 CONFIG_STANDALONE_LOAD_ADDR 3313 3314 This option defines a board specific value for the 3315 address where standalone program gets loaded, thus 3316 overwriting the architecture dependent default 3317 settings. 3318 3319- Frame Buffer Address: 3320 CONFIG_FB_ADDR 3321 3322 Define CONFIG_FB_ADDR if you want to use specific 3323 address for frame buffer. This is typically the case 3324 when using a graphics controller has separate video 3325 memory. U-Boot will then place the frame buffer at 3326 the given address instead of dynamically reserving it 3327 in system RAM by calling lcd_setmem(), which grabs 3328 the memory for the frame buffer depending on the 3329 configured panel size. 3330 3331 Please see board_init_f function. 3332 3333- Automatic software updates via TFTP server 3334 CONFIG_UPDATE_TFTP 3335 CONFIG_UPDATE_TFTP_CNT_MAX 3336 CONFIG_UPDATE_TFTP_MSEC_MAX 3337 3338 These options enable and control the auto-update feature; 3339 for a more detailed description refer to doc/README.update. 3340 3341- MTD Support (mtdparts command, UBI support) 3342 CONFIG_MTD_DEVICE 3343 3344 Adds the MTD device infrastructure from the Linux kernel. 3345 Needed for mtdparts command support. 3346 3347 CONFIG_MTD_PARTITIONS 3348 3349 Adds the MTD partitioning infrastructure from the Linux 3350 kernel. Needed for UBI support. 3351 3352- UBI support 3353 CONFIG_CMD_UBI 3354 3355 Adds commands for interacting with MTD partitions formatted 3356 with the UBI flash translation layer 3357 3358 Requires also defining CONFIG_RBTREE 3359 3360 CONFIG_UBI_SILENCE_MSG 3361 3362 Make the verbose messages from UBI stop printing. This leaves 3363 warnings and errors enabled. 3364 3365 3366 CONFIG_MTD_UBI_WL_THRESHOLD 3367 This parameter defines the maximum difference between the highest 3368 erase counter value and the lowest erase counter value of eraseblocks 3369 of UBI devices. When this threshold is exceeded, UBI starts performing 3370 wear leveling by means of moving data from eraseblock with low erase 3371 counter to eraseblocks with high erase counter. 3372 3373 The default value should be OK for SLC NAND flashes, NOR flashes and 3374 other flashes which have eraseblock life-cycle 100000 or more. 3375 However, in case of MLC NAND flashes which typically have eraseblock 3376 life-cycle less than 10000, the threshold should be lessened (e.g., 3377 to 128 or 256, although it does not have to be power of 2). 3378 3379 default: 4096 3380 3381 CONFIG_MTD_UBI_BEB_LIMIT 3382 This option specifies the maximum bad physical eraseblocks UBI 3383 expects on the MTD device (per 1024 eraseblocks). If the 3384 underlying flash does not admit of bad eraseblocks (e.g. NOR 3385 flash), this value is ignored. 3386 3387 NAND datasheets often specify the minimum and maximum NVM 3388 (Number of Valid Blocks) for the flashes' endurance lifetime. 3389 The maximum expected bad eraseblocks per 1024 eraseblocks 3390 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3391 which gives 20 for most NANDs (MaxNVB is basically the total 3392 count of eraseblocks on the chip). 3393 3394 To put it differently, if this value is 20, UBI will try to 3395 reserve about 1.9% of physical eraseblocks for bad blocks 3396 handling. And that will be 1.9% of eraseblocks on the entire 3397 NAND chip, not just the MTD partition UBI attaches. This means 3398 that if you have, say, a NAND flash chip admits maximum 40 bad 3399 eraseblocks, and it is split on two MTD partitions of the same 3400 size, UBI will reserve 40 eraseblocks when attaching a 3401 partition. 3402 3403 default: 20 3404 3405 CONFIG_MTD_UBI_FASTMAP 3406 Fastmap is a mechanism which allows attaching an UBI device 3407 in nearly constant time. Instead of scanning the whole MTD device it 3408 only has to locate a checkpoint (called fastmap) on the device. 3409 The on-flash fastmap contains all information needed to attach 3410 the device. Using fastmap makes only sense on large devices where 3411 attaching by scanning takes long. UBI will not automatically install 3412 a fastmap on old images, but you can set the UBI parameter 3413 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3414 that fastmap-enabled images are still usable with UBI implementations 3415 without fastmap support. On typical flash devices the whole fastmap 3416 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3417 3418 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3419 Set this parameter to enable fastmap automatically on images 3420 without a fastmap. 3421 default: 0 3422 3423 CONFIG_MTD_UBI_FM_DEBUG 3424 Enable UBI fastmap debug 3425 default: 0 3426 3427- UBIFS support 3428 CONFIG_CMD_UBIFS 3429 3430 Adds commands for interacting with UBI volumes formatted as 3431 UBIFS. UBIFS is read-only in u-boot. 3432 3433 Requires UBI support as well as CONFIG_LZO 3434 3435 CONFIG_UBIFS_SILENCE_MSG 3436 3437 Make the verbose messages from UBIFS stop printing. This leaves 3438 warnings and errors enabled. 3439 3440- SPL framework 3441 CONFIG_SPL 3442 Enable building of SPL globally. 3443 3444 CONFIG_SPL_LDSCRIPT 3445 LDSCRIPT for linking the SPL binary. 3446 3447 CONFIG_SPL_MAX_FOOTPRINT 3448 Maximum size in memory allocated to the SPL, BSS included. 3449 When defined, the linker checks that the actual memory 3450 used by SPL from _start to __bss_end does not exceed it. 3451 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3452 must not be both defined at the same time. 3453 3454 CONFIG_SPL_MAX_SIZE 3455 Maximum size of the SPL image (text, data, rodata, and 3456 linker lists sections), BSS excluded. 3457 When defined, the linker checks that the actual size does 3458 not exceed it. 3459 3460 CONFIG_SPL_TEXT_BASE 3461 TEXT_BASE for linking the SPL binary. 3462 3463 CONFIG_SPL_RELOC_TEXT_BASE 3464 Address to relocate to. If unspecified, this is equal to 3465 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3466 3467 CONFIG_SPL_BSS_START_ADDR 3468 Link address for the BSS within the SPL binary. 3469 3470 CONFIG_SPL_BSS_MAX_SIZE 3471 Maximum size in memory allocated to the SPL BSS. 3472 When defined, the linker checks that the actual memory used 3473 by SPL from __bss_start to __bss_end does not exceed it. 3474 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3475 must not be both defined at the same time. 3476 3477 CONFIG_SPL_STACK 3478 Adress of the start of the stack SPL will use 3479 3480 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3481 When defined, SPL will panic() if the image it has 3482 loaded does not have a signature. 3483 Defining this is useful when code which loads images 3484 in SPL cannot guarantee that absolutely all read errors 3485 will be caught. 3486 An example is the LPC32XX MLC NAND driver, which will 3487 consider that a completely unreadable NAND block is bad, 3488 and thus should be skipped silently. 3489 3490 CONFIG_SPL_ABORT_ON_RAW_IMAGE 3491 When defined, SPL will proceed to another boot method 3492 if the image it has loaded does not have a signature. 3493 3494 CONFIG_SPL_RELOC_STACK 3495 Adress of the start of the stack SPL will use after 3496 relocation. If unspecified, this is equal to 3497 CONFIG_SPL_STACK. 3498 3499 CONFIG_SYS_SPL_MALLOC_START 3500 Starting address of the malloc pool used in SPL. 3501 When this option is set the full malloc is used in SPL and 3502 it is set up by spl_init() and before that, the simple malloc() 3503 can be used if CONFIG_SYS_MALLOC_F is defined. 3504 3505 CONFIG_SYS_SPL_MALLOC_SIZE 3506 The size of the malloc pool used in SPL. 3507 3508 CONFIG_SPL_FRAMEWORK 3509 Enable the SPL framework under common/. This framework 3510 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3511 NAND loading of the Linux Kernel. 3512 3513 CONFIG_SPL_OS_BOOT 3514 Enable booting directly to an OS from SPL. 3515 See also: doc/README.falcon 3516 3517 CONFIG_SPL_DISPLAY_PRINT 3518 For ARM, enable an optional function to print more information 3519 about the running system. 3520 3521 CONFIG_SPL_INIT_MINIMAL 3522 Arch init code should be built for a very small image 3523 3524 CONFIG_SPL_LIBCOMMON_SUPPORT 3525 Support for common/libcommon.o in SPL binary 3526 3527 CONFIG_SPL_LIBDISK_SUPPORT 3528 Support for disk/libdisk.o in SPL binary 3529 3530 CONFIG_SPL_I2C_SUPPORT 3531 Support for drivers/i2c/libi2c.o in SPL binary 3532 3533 CONFIG_SPL_GPIO_SUPPORT 3534 Support for drivers/gpio/libgpio.o in SPL binary 3535 3536 CONFIG_SPL_MMC_SUPPORT 3537 Support for drivers/mmc/libmmc.o in SPL binary 3538 3539 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3540 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3541 Address and partition on the MMC to load U-Boot from 3542 when the MMC is being used in raw mode. 3543 3544 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3545 Partition on the MMC to load U-Boot from when the MMC is being 3546 used in raw mode 3547 3548 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3549 Sector to load kernel uImage from when MMC is being 3550 used in raw mode (for Falcon mode) 3551 3552 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3553 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3554 Sector and number of sectors to load kernel argument 3555 parameters from when MMC is being used in raw mode 3556 (for falcon mode) 3557 3558 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3559 Partition on the MMC to load U-Boot from when the MMC is being 3560 used in fs mode 3561 3562 CONFIG_SPL_FAT_SUPPORT 3563 Support for fs/fat/libfat.o in SPL binary 3564 3565 CONFIG_SPL_EXT_SUPPORT 3566 Support for EXT filesystem in SPL binary 3567 3568 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3569 Filename to read to load U-Boot when reading from filesystem 3570 3571 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3572 Filename to read to load kernel uImage when reading 3573 from filesystem (for Falcon mode) 3574 3575 CONFIG_SPL_FS_LOAD_ARGS_NAME 3576 Filename to read to load kernel argument parameters 3577 when reading from filesystem (for Falcon mode) 3578 3579 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3580 Set this for NAND SPL on PPC mpc83xx targets, so that 3581 start.S waits for the rest of the SPL to load before 3582 continuing (the hardware starts execution after just 3583 loading the first page rather than the full 4K). 3584 3585 CONFIG_SPL_SKIP_RELOCATE 3586 Avoid SPL relocation 3587 3588 CONFIG_SPL_NAND_BASE 3589 Include nand_base.c in the SPL. Requires 3590 CONFIG_SPL_NAND_DRIVERS. 3591 3592 CONFIG_SPL_NAND_DRIVERS 3593 SPL uses normal NAND drivers, not minimal drivers. 3594 3595 CONFIG_SPL_NAND_ECC 3596 Include standard software ECC in the SPL 3597 3598 CONFIG_SPL_NAND_SIMPLE 3599 Support for NAND boot using simple NAND drivers that 3600 expose the cmd_ctrl() interface. 3601 3602 CONFIG_SPL_MTD_SUPPORT 3603 Support for the MTD subsystem within SPL. Useful for 3604 environment on NAND support within SPL. 3605 3606 CONFIG_SPL_NAND_RAW_ONLY 3607 Support to boot only raw u-boot.bin images. Use this only 3608 if you need to save space. 3609 3610 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3611 Set for the SPL on PPC mpc8xxx targets, support for 3612 drivers/ddr/fsl/libddr.o in SPL binary. 3613 3614 CONFIG_SPL_COMMON_INIT_DDR 3615 Set for common ddr init with serial presence detect in 3616 SPL binary. 3617 3618 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3619 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3620 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3621 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3622 CONFIG_SYS_NAND_ECCBYTES 3623 Defines the size and behavior of the NAND that SPL uses 3624 to read U-Boot 3625 3626 CONFIG_SPL_NAND_BOOT 3627 Add support NAND boot 3628 3629 CONFIG_SYS_NAND_U_BOOT_OFFS 3630 Location in NAND to read U-Boot from 3631 3632 CONFIG_SYS_NAND_U_BOOT_DST 3633 Location in memory to load U-Boot to 3634 3635 CONFIG_SYS_NAND_U_BOOT_SIZE 3636 Size of image to load 3637 3638 CONFIG_SYS_NAND_U_BOOT_START 3639 Entry point in loaded image to jump to 3640 3641 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3642 Define this if you need to first read the OOB and then the 3643 data. This is used, for example, on davinci platforms. 3644 3645 CONFIG_SPL_OMAP3_ID_NAND 3646 Support for an OMAP3-specific set of functions to return the 3647 ID and MFR of the first attached NAND chip, if present. 3648 3649 CONFIG_SPL_SERIAL_SUPPORT 3650 Support for drivers/serial/libserial.o in SPL binary 3651 3652 CONFIG_SPL_SPI_FLASH_SUPPORT 3653 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3654 3655 CONFIG_SPL_SPI_SUPPORT 3656 Support for drivers/spi/libspi.o in SPL binary 3657 3658 CONFIG_SPL_RAM_DEVICE 3659 Support for running image already present in ram, in SPL binary 3660 3661 CONFIG_SPL_LIBGENERIC_SUPPORT 3662 Support for lib/libgeneric.o in SPL binary 3663 3664 CONFIG_SPL_ENV_SUPPORT 3665 Support for the environment operating in SPL binary 3666 3667 CONFIG_SPL_NET_SUPPORT 3668 Support for the net/libnet.o in SPL binary. 3669 It conflicts with SPL env from storage medium specified by 3670 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3671 3672 CONFIG_SPL_PAD_TO 3673 Image offset to which the SPL should be padded before appending 3674 the SPL payload. By default, this is defined as 3675 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3676 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3677 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3678 3679 CONFIG_SPL_TARGET 3680 Final target image containing SPL and payload. Some SPLs 3681 use an arch-specific makefile fragment instead, for 3682 example if more than one image needs to be produced. 3683 3684 CONFIG_FIT_SPL_PRINT 3685 Printing information about a FIT image adds quite a bit of 3686 code to SPL. So this is normally disabled in SPL. Use this 3687 option to re-enable it. This will affect the output of the 3688 bootm command when booting a FIT image. 3689 3690- TPL framework 3691 CONFIG_TPL 3692 Enable building of TPL globally. 3693 3694 CONFIG_TPL_PAD_TO 3695 Image offset to which the TPL should be padded before appending 3696 the TPL payload. By default, this is defined as 3697 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3698 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3699 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3700 3701- Interrupt support (PPC): 3702 3703 There are common interrupt_init() and timer_interrupt() 3704 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3705 for CPU specific initialization. interrupt_init_cpu() 3706 should set decrementer_count to appropriate value. If 3707 CPU resets decrementer automatically after interrupt 3708 (ppc4xx) it should set decrementer_count to zero. 3709 timer_interrupt() calls timer_interrupt_cpu() for CPU 3710 specific handling. If board has watchdog / status_led 3711 / other_activity_monitor it works automatically from 3712 general timer_interrupt(). 3713 3714 3715Board initialization settings: 3716------------------------------ 3717 3718During Initialization u-boot calls a number of board specific functions 3719to allow the preparation of board specific prerequisites, e.g. pin setup 3720before drivers are initialized. To enable these callbacks the 3721following configuration macros have to be defined. Currently this is 3722architecture specific, so please check arch/your_architecture/lib/board.c 3723typically in board_init_f() and board_init_r(). 3724 3725- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3726- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3727- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3728- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3729 3730Configuration Settings: 3731----------------------- 3732 3733- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3734 Optionally it can be defined to support 64-bit memory commands. 3735 3736- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3737 undefine this when you're short of memory. 3738 3739- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3740 width of the commands listed in the 'help' command output. 3741 3742- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3743 prompt for user input. 3744 3745- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3746 3747- CONFIG_SYS_PBSIZE: Buffer size for Console output 3748 3749- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3750 3751- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3752 the application (usually a Linux kernel) when it is 3753 booted 3754 3755- CONFIG_SYS_BAUDRATE_TABLE: 3756 List of legal baudrate settings for this board. 3757 3758- CONFIG_SYS_CONSOLE_INFO_QUIET 3759 Suppress display of console information at boot. 3760 3761- CONFIG_SYS_CONSOLE_IS_IN_ENV 3762 If the board specific function 3763 extern int overwrite_console (void); 3764 returns 1, the stdin, stderr and stdout are switched to the 3765 serial port, else the settings in the environment are used. 3766 3767- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3768 Enable the call to overwrite_console(). 3769 3770- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3771 Enable overwrite of previous console environment settings. 3772 3773- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3774 Begin and End addresses of the area used by the 3775 simple memory test. 3776 3777- CONFIG_SYS_ALT_MEMTEST: 3778 Enable an alternate, more extensive memory test. 3779 3780- CONFIG_SYS_MEMTEST_SCRATCH: 3781 Scratch address used by the alternate memory test 3782 You only need to set this if address zero isn't writeable 3783 3784- CONFIG_SYS_MEM_RESERVE_SECURE 3785 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3786 is substracted from total RAM and won't be reported to OS. 3787 This memory can be used as secure memory. A variable 3788 gd->secure_ram is used to track the location. In systems 3789 the RAM base is not zero, or RAM is divided into banks, 3790 this variable needs to be recalcuated to get the address. 3791 3792- CONFIG_SYS_MEM_TOP_HIDE: 3793 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3794 this specified memory area will get subtracted from the top 3795 (end) of RAM and won't get "touched" at all by U-Boot. By 3796 fixing up gd->ram_size the Linux kernel should gets passed 3797 the now "corrected" memory size and won't touch it either. 3798 This should work for arch/ppc and arch/powerpc. Only Linux 3799 board ports in arch/powerpc with bootwrapper support that 3800 recalculate the memory size from the SDRAM controller setup 3801 will have to get fixed in Linux additionally. 3802 3803 This option can be used as a workaround for the 440EPx/GRx 3804 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3805 be touched. 3806 3807 WARNING: Please make sure that this value is a multiple of 3808 the Linux page size (normally 4k). If this is not the case, 3809 then the end address of the Linux memory will be located at a 3810 non page size aligned address and this could cause major 3811 problems. 3812 3813- CONFIG_SYS_LOADS_BAUD_CHANGE: 3814 Enable temporary baudrate change while serial download 3815 3816- CONFIG_SYS_SDRAM_BASE: 3817 Physical start address of SDRAM. _Must_ be 0 here. 3818 3819- CONFIG_SYS_MBIO_BASE: 3820 Physical start address of Motherboard I/O (if using a 3821 Cogent motherboard) 3822 3823- CONFIG_SYS_FLASH_BASE: 3824 Physical start address of Flash memory. 3825 3826- CONFIG_SYS_MONITOR_BASE: 3827 Physical start address of boot monitor code (set by 3828 make config files to be same as the text base address 3829 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3830 CONFIG_SYS_FLASH_BASE when booting from flash. 3831 3832- CONFIG_SYS_MONITOR_LEN: 3833 Size of memory reserved for monitor code, used to 3834 determine _at_compile_time_ (!) if the environment is 3835 embedded within the U-Boot image, or in a separate 3836 flash sector. 3837 3838- CONFIG_SYS_MALLOC_LEN: 3839 Size of DRAM reserved for malloc() use. 3840 3841- CONFIG_SYS_MALLOC_F_LEN 3842 Size of the malloc() pool for use before relocation. If 3843 this is defined, then a very simple malloc() implementation 3844 will become available before relocation. The address is just 3845 below the global data, and the stack is moved down to make 3846 space. 3847 3848 This feature allocates regions with increasing addresses 3849 within the region. calloc() is supported, but realloc() 3850 is not available. free() is supported but does nothing. 3851 The memory will be freed (or in fact just forgotten) when 3852 U-Boot relocates itself. 3853 3854 Pre-relocation malloc() is only supported on ARM and sandbox 3855 at present but is fairly easy to enable for other archs. 3856 3857- CONFIG_SYS_MALLOC_SIMPLE 3858 Provides a simple and small malloc() and calloc() for those 3859 boards which do not use the full malloc in SPL (which is 3860 enabled with CONFIG_SYS_SPL_MALLOC_START). 3861 3862- CONFIG_SYS_NONCACHED_MEMORY: 3863 Size of non-cached memory area. This area of memory will be 3864 typically located right below the malloc() area and mapped 3865 uncached in the MMU. This is useful for drivers that would 3866 otherwise require a lot of explicit cache maintenance. For 3867 some drivers it's also impossible to properly maintain the 3868 cache. For example if the regions that need to be flushed 3869 are not a multiple of the cache-line size, *and* padding 3870 cannot be allocated between the regions to align them (i.e. 3871 if the HW requires a contiguous array of regions, and the 3872 size of each region is not cache-aligned), then a flush of 3873 one region may result in overwriting data that hardware has 3874 written to another region in the same cache-line. This can 3875 happen for example in network drivers where descriptors for 3876 buffers are typically smaller than the CPU cache-line (e.g. 3877 16 bytes vs. 32 or 64 bytes). 3878 3879 Non-cached memory is only supported on 32-bit ARM at present. 3880 3881- CONFIG_SYS_BOOTM_LEN: 3882 Normally compressed uImages are limited to an 3883 uncompressed size of 8 MBytes. If this is not enough, 3884 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3885 to adjust this setting to your needs. 3886 3887- CONFIG_SYS_BOOTMAPSZ: 3888 Maximum size of memory mapped by the startup code of 3889 the Linux kernel; all data that must be processed by 3890 the Linux kernel (bd_info, boot arguments, FDT blob if 3891 used) must be put below this limit, unless "bootm_low" 3892 environment variable is defined and non-zero. In such case 3893 all data for the Linux kernel must be between "bootm_low" 3894 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3895 variable "bootm_mapsize" will override the value of 3896 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3897 then the value in "bootm_size" will be used instead. 3898 3899- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3900 Enable initrd_high functionality. If defined then the 3901 initrd_high feature is enabled and the bootm ramdisk subcommand 3902 is enabled. 3903 3904- CONFIG_SYS_BOOT_GET_CMDLINE: 3905 Enables allocating and saving kernel cmdline in space between 3906 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3907 3908- CONFIG_SYS_BOOT_GET_KBD: 3909 Enables allocating and saving a kernel copy of the bd_info in 3910 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3911 3912- CONFIG_SYS_MAX_FLASH_BANKS: 3913 Max number of Flash memory banks 3914 3915- CONFIG_SYS_MAX_FLASH_SECT: 3916 Max number of sectors on a Flash chip 3917 3918- CONFIG_SYS_FLASH_ERASE_TOUT: 3919 Timeout for Flash erase operations (in ms) 3920 3921- CONFIG_SYS_FLASH_WRITE_TOUT: 3922 Timeout for Flash write operations (in ms) 3923 3924- CONFIG_SYS_FLASH_LOCK_TOUT 3925 Timeout for Flash set sector lock bit operation (in ms) 3926 3927- CONFIG_SYS_FLASH_UNLOCK_TOUT 3928 Timeout for Flash clear lock bits operation (in ms) 3929 3930- CONFIG_SYS_FLASH_PROTECTION 3931 If defined, hardware flash sectors protection is used 3932 instead of U-Boot software protection. 3933 3934- CONFIG_SYS_DIRECT_FLASH_TFTP: 3935 3936 Enable TFTP transfers directly to flash memory; 3937 without this option such a download has to be 3938 performed in two steps: (1) download to RAM, and (2) 3939 copy from RAM to flash. 3940 3941 The two-step approach is usually more reliable, since 3942 you can check if the download worked before you erase 3943 the flash, but in some situations (when system RAM is 3944 too limited to allow for a temporary copy of the 3945 downloaded image) this option may be very useful. 3946 3947- CONFIG_SYS_FLASH_CFI: 3948 Define if the flash driver uses extra elements in the 3949 common flash structure for storing flash geometry. 3950 3951- CONFIG_FLASH_CFI_DRIVER 3952 This option also enables the building of the cfi_flash driver 3953 in the drivers directory 3954 3955- CONFIG_FLASH_CFI_MTD 3956 This option enables the building of the cfi_mtd driver 3957 in the drivers directory. The driver exports CFI flash 3958 to the MTD layer. 3959 3960- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3961 Use buffered writes to flash. 3962 3963- CONFIG_FLASH_SPANSION_S29WS_N 3964 s29ws-n MirrorBit flash has non-standard addresses for buffered 3965 write commands. 3966 3967- CONFIG_SYS_FLASH_QUIET_TEST 3968 If this option is defined, the common CFI flash doesn't 3969 print it's warning upon not recognized FLASH banks. This 3970 is useful, if some of the configured banks are only 3971 optionally available. 3972 3973- CONFIG_FLASH_SHOW_PROGRESS 3974 If defined (must be an integer), print out countdown 3975 digits and dots. Recommended value: 45 (9..1) for 80 3976 column displays, 15 (3..1) for 40 column displays. 3977 3978- CONFIG_FLASH_VERIFY 3979 If defined, the content of the flash (destination) is compared 3980 against the source after the write operation. An error message 3981 will be printed when the contents are not identical. 3982 Please note that this option is useless in nearly all cases, 3983 since such flash programming errors usually are detected earlier 3984 while unprotecting/erasing/programming. Please only enable 3985 this option if you really know what you are doing. 3986 3987- CONFIG_SYS_RX_ETH_BUFFER: 3988 Defines the number of Ethernet receive buffers. On some 3989 Ethernet controllers it is recommended to set this value 3990 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3991 buffers can be full shortly after enabling the interface 3992 on high Ethernet traffic. 3993 Defaults to 4 if not defined. 3994 3995- CONFIG_ENV_MAX_ENTRIES 3996 3997 Maximum number of entries in the hash table that is used 3998 internally to store the environment settings. The default 3999 setting is supposed to be generous and should work in most 4000 cases. This setting can be used to tune behaviour; see 4001 lib/hashtable.c for details. 4002 4003- CONFIG_ENV_FLAGS_LIST_DEFAULT 4004- CONFIG_ENV_FLAGS_LIST_STATIC 4005 Enable validation of the values given to environment variables when 4006 calling env set. Variables can be restricted to only decimal, 4007 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4008 the variables can also be restricted to IP address or MAC address. 4009 4010 The format of the list is: 4011 type_attribute = [s|d|x|b|i|m] 4012 access_attribute = [a|r|o|c] 4013 attributes = type_attribute[access_attribute] 4014 entry = variable_name[:attributes] 4015 list = entry[,list] 4016 4017 The type attributes are: 4018 s - String (default) 4019 d - Decimal 4020 x - Hexadecimal 4021 b - Boolean ([1yYtT|0nNfF]) 4022 i - IP address 4023 m - MAC address 4024 4025 The access attributes are: 4026 a - Any (default) 4027 r - Read-only 4028 o - Write-once 4029 c - Change-default 4030 4031 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4032 Define this to a list (string) to define the ".flags" 4033 environment variable in the default or embedded environment. 4034 4035 - CONFIG_ENV_FLAGS_LIST_STATIC 4036 Define this to a list (string) to define validation that 4037 should be done if an entry is not found in the ".flags" 4038 environment variable. To override a setting in the static 4039 list, simply add an entry for the same variable name to the 4040 ".flags" variable. 4041 4042 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4043 regular expression. This allows multiple variables to define the same 4044 flags without explicitly listing them for each variable. 4045 4046- CONFIG_ENV_ACCESS_IGNORE_FORCE 4047 If defined, don't allow the -f switch to env set override variable 4048 access flags. 4049 4050- CONFIG_SYS_GENERIC_BOARD 4051 This selects the architecture-generic board system instead of the 4052 architecture-specific board files. It is intended to move boards 4053 to this new framework over time. Defining this will disable the 4054 arch/foo/lib/board.c file and use common/board_f.c and 4055 common/board_r.c instead. To use this option your architecture 4056 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig). 4057 If you find problems enabling this option on your board please report 4058 the problem and send patches! 4059 4060- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4061 This is set by OMAP boards for the max time that reset should 4062 be asserted. See doc/README.omap-reset-time for details on how 4063 the value can be calculated on a given board. 4064 4065- CONFIG_USE_STDINT 4066 If stdint.h is available with your toolchain you can define this 4067 option to enable it. You can provide option 'USE_STDINT=1' when 4068 building U-Boot to enable this. 4069 4070The following definitions that deal with the placement and management 4071of environment data (variable area); in general, we support the 4072following configurations: 4073 4074- CONFIG_BUILD_ENVCRC: 4075 4076 Builds up envcrc with the target environment so that external utils 4077 may easily extract it and embed it in final U-Boot images. 4078 4079- CONFIG_ENV_IS_IN_FLASH: 4080 4081 Define this if the environment is in flash memory. 4082 4083 a) The environment occupies one whole flash sector, which is 4084 "embedded" in the text segment with the U-Boot code. This 4085 happens usually with "bottom boot sector" or "top boot 4086 sector" type flash chips, which have several smaller 4087 sectors at the start or the end. For instance, such a 4088 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4089 such a case you would place the environment in one of the 4090 4 kB sectors - with U-Boot code before and after it. With 4091 "top boot sector" type flash chips, you would put the 4092 environment in one of the last sectors, leaving a gap 4093 between U-Boot and the environment. 4094 4095 - CONFIG_ENV_OFFSET: 4096 4097 Offset of environment data (variable area) to the 4098 beginning of flash memory; for instance, with bottom boot 4099 type flash chips the second sector can be used: the offset 4100 for this sector is given here. 4101 4102 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4103 4104 - CONFIG_ENV_ADDR: 4105 4106 This is just another way to specify the start address of 4107 the flash sector containing the environment (instead of 4108 CONFIG_ENV_OFFSET). 4109 4110 - CONFIG_ENV_SECT_SIZE: 4111 4112 Size of the sector containing the environment. 4113 4114 4115 b) Sometimes flash chips have few, equal sized, BIG sectors. 4116 In such a case you don't want to spend a whole sector for 4117 the environment. 4118 4119 - CONFIG_ENV_SIZE: 4120 4121 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4122 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4123 of this flash sector for the environment. This saves 4124 memory for the RAM copy of the environment. 4125 4126 It may also save flash memory if you decide to use this 4127 when your environment is "embedded" within U-Boot code, 4128 since then the remainder of the flash sector could be used 4129 for U-Boot code. It should be pointed out that this is 4130 STRONGLY DISCOURAGED from a robustness point of view: 4131 updating the environment in flash makes it always 4132 necessary to erase the WHOLE sector. If something goes 4133 wrong before the contents has been restored from a copy in 4134 RAM, your target system will be dead. 4135 4136 - CONFIG_ENV_ADDR_REDUND 4137 CONFIG_ENV_SIZE_REDUND 4138 4139 These settings describe a second storage area used to hold 4140 a redundant copy of the environment data, so that there is 4141 a valid backup copy in case there is a power failure during 4142 a "saveenv" operation. 4143 4144BE CAREFUL! Any changes to the flash layout, and some changes to the 4145source code will make it necessary to adapt <board>/u-boot.lds* 4146accordingly! 4147 4148 4149- CONFIG_ENV_IS_IN_NVRAM: 4150 4151 Define this if you have some non-volatile memory device 4152 (NVRAM, battery buffered SRAM) which you want to use for the 4153 environment. 4154 4155 - CONFIG_ENV_ADDR: 4156 - CONFIG_ENV_SIZE: 4157 4158 These two #defines are used to determine the memory area you 4159 want to use for environment. It is assumed that this memory 4160 can just be read and written to, without any special 4161 provision. 4162 4163BE CAREFUL! The first access to the environment happens quite early 4164in U-Boot initialization (when we try to get the setting of for the 4165console baudrate). You *MUST* have mapped your NVRAM area then, or 4166U-Boot will hang. 4167 4168Please note that even with NVRAM we still use a copy of the 4169environment in RAM: we could work on NVRAM directly, but we want to 4170keep settings there always unmodified except somebody uses "saveenv" 4171to save the current settings. 4172 4173 4174- CONFIG_ENV_IS_IN_EEPROM: 4175 4176 Use this if you have an EEPROM or similar serial access 4177 device and a driver for it. 4178 4179 - CONFIG_ENV_OFFSET: 4180 - CONFIG_ENV_SIZE: 4181 4182 These two #defines specify the offset and size of the 4183 environment area within the total memory of your EEPROM. 4184 4185 - CONFIG_SYS_I2C_EEPROM_ADDR: 4186 If defined, specified the chip address of the EEPROM device. 4187 The default address is zero. 4188 4189 - CONFIG_SYS_I2C_EEPROM_BUS: 4190 If defined, specified the i2c bus of the EEPROM device. 4191 4192 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4193 If defined, the number of bits used to address bytes in a 4194 single page in the EEPROM device. A 64 byte page, for example 4195 would require six bits. 4196 4197 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4198 If defined, the number of milliseconds to delay between 4199 page writes. The default is zero milliseconds. 4200 4201 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4202 The length in bytes of the EEPROM memory array address. Note 4203 that this is NOT the chip address length! 4204 4205 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4206 EEPROM chips that implement "address overflow" are ones 4207 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4208 address and the extra bits end up in the "chip address" bit 4209 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4210 byte chips. 4211 4212 Note that we consider the length of the address field to 4213 still be one byte because the extra address bits are hidden 4214 in the chip address. 4215 4216 - CONFIG_SYS_EEPROM_SIZE: 4217 The size in bytes of the EEPROM device. 4218 4219 - CONFIG_ENV_EEPROM_IS_ON_I2C 4220 define this, if you have I2C and SPI activated, and your 4221 EEPROM, which holds the environment, is on the I2C bus. 4222 4223 - CONFIG_I2C_ENV_EEPROM_BUS 4224 if you have an Environment on an EEPROM reached over 4225 I2C muxes, you can define here, how to reach this 4226 EEPROM. For example: 4227 4228 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4229 4230 EEPROM which holds the environment, is reached over 4231 a pca9547 i2c mux with address 0x70, channel 3. 4232 4233- CONFIG_ENV_IS_IN_DATAFLASH: 4234 4235 Define this if you have a DataFlash memory device which you 4236 want to use for the environment. 4237 4238 - CONFIG_ENV_OFFSET: 4239 - CONFIG_ENV_ADDR: 4240 - CONFIG_ENV_SIZE: 4241 4242 These three #defines specify the offset and size of the 4243 environment area within the total memory of your DataFlash placed 4244 at the specified address. 4245 4246- CONFIG_ENV_IS_IN_SPI_FLASH: 4247 4248 Define this if you have a SPI Flash memory device which you 4249 want to use for the environment. 4250 4251 - CONFIG_ENV_OFFSET: 4252 - CONFIG_ENV_SIZE: 4253 4254 These two #defines specify the offset and size of the 4255 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4256 aligned to an erase sector boundary. 4257 4258 - CONFIG_ENV_SECT_SIZE: 4259 4260 Define the SPI flash's sector size. 4261 4262 - CONFIG_ENV_OFFSET_REDUND (optional): 4263 4264 This setting describes a second storage area of CONFIG_ENV_SIZE 4265 size used to hold a redundant copy of the environment data, so 4266 that there is a valid backup copy in case there is a power failure 4267 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4268 aligned to an erase sector boundary. 4269 4270 - CONFIG_ENV_SPI_BUS (optional): 4271 - CONFIG_ENV_SPI_CS (optional): 4272 4273 Define the SPI bus and chip select. If not defined they will be 0. 4274 4275 - CONFIG_ENV_SPI_MAX_HZ (optional): 4276 4277 Define the SPI max work clock. If not defined then use 1MHz. 4278 4279 - CONFIG_ENV_SPI_MODE (optional): 4280 4281 Define the SPI work mode. If not defined then use SPI_MODE_3. 4282 4283- CONFIG_ENV_IS_IN_REMOTE: 4284 4285 Define this if you have a remote memory space which you 4286 want to use for the local device's environment. 4287 4288 - CONFIG_ENV_ADDR: 4289 - CONFIG_ENV_SIZE: 4290 4291 These two #defines specify the address and size of the 4292 environment area within the remote memory space. The 4293 local device can get the environment from remote memory 4294 space by SRIO or PCIE links. 4295 4296BE CAREFUL! For some special cases, the local device can not use 4297"saveenv" command. For example, the local device will get the 4298environment stored in a remote NOR flash by SRIO or PCIE link, 4299but it can not erase, write this NOR flash by SRIO or PCIE interface. 4300 4301- CONFIG_ENV_IS_IN_NAND: 4302 4303 Define this if you have a NAND device which you want to use 4304 for the environment. 4305 4306 - CONFIG_ENV_OFFSET: 4307 - CONFIG_ENV_SIZE: 4308 4309 These two #defines specify the offset and size of the environment 4310 area within the first NAND device. CONFIG_ENV_OFFSET must be 4311 aligned to an erase block boundary. 4312 4313 - CONFIG_ENV_OFFSET_REDUND (optional): 4314 4315 This setting describes a second storage area of CONFIG_ENV_SIZE 4316 size used to hold a redundant copy of the environment data, so 4317 that there is a valid backup copy in case there is a power failure 4318 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4319 aligned to an erase block boundary. 4320 4321 - CONFIG_ENV_RANGE (optional): 4322 4323 Specifies the length of the region in which the environment 4324 can be written. This should be a multiple of the NAND device's 4325 block size. Specifying a range with more erase blocks than 4326 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4327 the range to be avoided. 4328 4329 - CONFIG_ENV_OFFSET_OOB (optional): 4330 4331 Enables support for dynamically retrieving the offset of the 4332 environment from block zero's out-of-band data. The 4333 "nand env.oob" command can be used to record this offset. 4334 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4335 using CONFIG_ENV_OFFSET_OOB. 4336 4337- CONFIG_NAND_ENV_DST 4338 4339 Defines address in RAM to which the nand_spl code should copy the 4340 environment. If redundant environment is used, it will be copied to 4341 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4342 4343- CONFIG_ENV_IS_IN_UBI: 4344 4345 Define this if you have an UBI volume that you want to use for the 4346 environment. This has the benefit of wear-leveling the environment 4347 accesses, which is important on NAND. 4348 4349 - CONFIG_ENV_UBI_PART: 4350 4351 Define this to a string that is the mtd partition containing the UBI. 4352 4353 - CONFIG_ENV_UBI_VOLUME: 4354 4355 Define this to the name of the volume that you want to store the 4356 environment in. 4357 4358 - CONFIG_ENV_UBI_VOLUME_REDUND: 4359 4360 Define this to the name of another volume to store a second copy of 4361 the environment in. This will enable redundant environments in UBI. 4362 It is assumed that both volumes are in the same MTD partition. 4363 4364 - CONFIG_UBI_SILENCE_MSG 4365 - CONFIG_UBIFS_SILENCE_MSG 4366 4367 You will probably want to define these to avoid a really noisy system 4368 when storing the env in UBI. 4369 4370- CONFIG_ENV_IS_IN_FAT: 4371 Define this if you want to use the FAT file system for the environment. 4372 4373 - FAT_ENV_INTERFACE: 4374 4375 Define this to a string that is the name of the block device. 4376 4377 - FAT_ENV_DEV_AND_PART: 4378 4379 Define this to a string to specify the partition of the device. It can 4380 be as following: 4381 4382 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4383 - "D:P": device D partition P. Error occurs if device D has no 4384 partition table. 4385 - "D:0": device D. 4386 - "D" or "D:": device D partition 1 if device D has partition 4387 table, or the whole device D if has no partition 4388 table. 4389 - "D:auto": first partition in device D with bootable flag set. 4390 If none, first valid partition in device D. If no 4391 partition table then means device D. 4392 4393 - FAT_ENV_FILE: 4394 4395 It's a string of the FAT file name. This file use to store the 4396 environment. 4397 4398 - CONFIG_FAT_WRITE: 4399 This should be defined. Otherwise it cannot save the environment file. 4400 4401- CONFIG_ENV_IS_IN_MMC: 4402 4403 Define this if you have an MMC device which you want to use for the 4404 environment. 4405 4406 - CONFIG_SYS_MMC_ENV_DEV: 4407 4408 Specifies which MMC device the environment is stored in. 4409 4410 - CONFIG_SYS_MMC_ENV_PART (optional): 4411 4412 Specifies which MMC partition the environment is stored in. If not 4413 set, defaults to partition 0, the user area. Common values might be 4414 1 (first MMC boot partition), 2 (second MMC boot partition). 4415 4416 - CONFIG_ENV_OFFSET: 4417 - CONFIG_ENV_SIZE: 4418 4419 These two #defines specify the offset and size of the environment 4420 area within the specified MMC device. 4421 4422 If offset is positive (the usual case), it is treated as relative to 4423 the start of the MMC partition. If offset is negative, it is treated 4424 as relative to the end of the MMC partition. This can be useful if 4425 your board may be fitted with different MMC devices, which have 4426 different sizes for the MMC partitions, and you always want the 4427 environment placed at the very end of the partition, to leave the 4428 maximum possible space before it, to store other data. 4429 4430 These two values are in units of bytes, but must be aligned to an 4431 MMC sector boundary. 4432 4433 - CONFIG_ENV_OFFSET_REDUND (optional): 4434 4435 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4436 hold a redundant copy of the environment data. This provides a 4437 valid backup copy in case the other copy is corrupted, e.g. due 4438 to a power failure during a "saveenv" operation. 4439 4440 This value may also be positive or negative; this is handled in the 4441 same way as CONFIG_ENV_OFFSET. 4442 4443 This value is also in units of bytes, but must also be aligned to 4444 an MMC sector boundary. 4445 4446 - CONFIG_ENV_SIZE_REDUND (optional): 4447 4448 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4449 set. If this value is set, it must be set to the same value as 4450 CONFIG_ENV_SIZE. 4451 4452- CONFIG_SYS_SPI_INIT_OFFSET 4453 4454 Defines offset to the initial SPI buffer area in DPRAM. The 4455 area is used at an early stage (ROM part) if the environment 4456 is configured to reside in the SPI EEPROM: We need a 520 byte 4457 scratch DPRAM area. It is used between the two initialization 4458 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4459 to be a good choice since it makes it far enough from the 4460 start of the data area as well as from the stack pointer. 4461 4462Please note that the environment is read-only until the monitor 4463has been relocated to RAM and a RAM copy of the environment has been 4464created; also, when using EEPROM you will have to use getenv_f() 4465until then to read environment variables. 4466 4467The environment is protected by a CRC32 checksum. Before the monitor 4468is relocated into RAM, as a result of a bad CRC you will be working 4469with the compiled-in default environment - *silently*!!! [This is 4470necessary, because the first environment variable we need is the 4471"baudrate" setting for the console - if we have a bad CRC, we don't 4472have any device yet where we could complain.] 4473 4474Note: once the monitor has been relocated, then it will complain if 4475the default environment is used; a new CRC is computed as soon as you 4476use the "saveenv" command to store a valid environment. 4477 4478- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4479 Echo the inverted Ethernet link state to the fault LED. 4480 4481 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4482 also needs to be defined. 4483 4484- CONFIG_SYS_FAULT_MII_ADDR: 4485 MII address of the PHY to check for the Ethernet link state. 4486 4487- CONFIG_NS16550_MIN_FUNCTIONS: 4488 Define this if you desire to only have use of the NS16550_init 4489 and NS16550_putc functions for the serial driver located at 4490 drivers/serial/ns16550.c. This option is useful for saving 4491 space for already greatly restricted images, including but not 4492 limited to NAND_SPL configurations. 4493 4494- CONFIG_DISPLAY_BOARDINFO 4495 Display information about the board that U-Boot is running on 4496 when U-Boot starts up. The board function checkboard() is called 4497 to do this. 4498 4499- CONFIG_DISPLAY_BOARDINFO_LATE 4500 Similar to the previous option, but display this information 4501 later, once stdio is running and output goes to the LCD, if 4502 present. 4503 4504- CONFIG_BOARD_SIZE_LIMIT: 4505 Maximum size of the U-Boot image. When defined, the 4506 build system checks that the actual size does not 4507 exceed it. 4508 4509Low Level (hardware related) configuration options: 4510--------------------------------------------------- 4511 4512- CONFIG_SYS_CACHELINE_SIZE: 4513 Cache Line Size of the CPU. 4514 4515- CONFIG_SYS_DEFAULT_IMMR: 4516 Default address of the IMMR after system reset. 4517 4518 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4519 and RPXsuper) to be able to adjust the position of 4520 the IMMR register after a reset. 4521 4522- CONFIG_SYS_CCSRBAR_DEFAULT: 4523 Default (power-on reset) physical address of CCSR on Freescale 4524 PowerPC SOCs. 4525 4526- CONFIG_SYS_CCSRBAR: 4527 Virtual address of CCSR. On a 32-bit build, this is typically 4528 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4529 4530 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4531 for cross-platform code that uses that macro instead. 4532 4533- CONFIG_SYS_CCSRBAR_PHYS: 4534 Physical address of CCSR. CCSR can be relocated to a new 4535 physical address, if desired. In this case, this macro should 4536 be set to that address. Otherwise, it should be set to the 4537 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4538 is typically relocated on 36-bit builds. It is recommended 4539 that this macro be defined via the _HIGH and _LOW macros: 4540 4541 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4542 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4543 4544- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4545 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4546 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4547 used in assembly code, so it must not contain typecasts or 4548 integer size suffixes (e.g. "ULL"). 4549 4550- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4551 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4552 used in assembly code, so it must not contain typecasts or 4553 integer size suffixes (e.g. "ULL"). 4554 4555- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4556 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4557 forced to a value that ensures that CCSR is not relocated. 4558 4559- Floppy Disk Support: 4560 CONFIG_SYS_FDC_DRIVE_NUMBER 4561 4562 the default drive number (default value 0) 4563 4564 CONFIG_SYS_ISA_IO_STRIDE 4565 4566 defines the spacing between FDC chipset registers 4567 (default value 1) 4568 4569 CONFIG_SYS_ISA_IO_OFFSET 4570 4571 defines the offset of register from address. It 4572 depends on which part of the data bus is connected to 4573 the FDC chipset. (default value 0) 4574 4575 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4576 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4577 default value. 4578 4579 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4580 fdc_hw_init() is called at the beginning of the FDC 4581 setup. fdc_hw_init() must be provided by the board 4582 source code. It is used to make hardware-dependent 4583 initializations. 4584 4585- CONFIG_IDE_AHB: 4586 Most IDE controllers were designed to be connected with PCI 4587 interface. Only few of them were designed for AHB interface. 4588 When software is doing ATA command and data transfer to 4589 IDE devices through IDE-AHB controller, some additional 4590 registers accessing to these kind of IDE-AHB controller 4591 is required. 4592 4593- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4594 DO NOT CHANGE unless you know exactly what you're 4595 doing! (11-4) [MPC8xx/82xx systems only] 4596 4597- CONFIG_SYS_INIT_RAM_ADDR: 4598 4599 Start address of memory area that can be used for 4600 initial data and stack; please note that this must be 4601 writable memory that is working WITHOUT special 4602 initialization, i. e. you CANNOT use normal RAM which 4603 will become available only after programming the 4604 memory controller and running certain initialization 4605 sequences. 4606 4607 U-Boot uses the following memory types: 4608 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4609 - MPC824X: data cache 4610 - PPC4xx: data cache 4611 4612- CONFIG_SYS_GBL_DATA_OFFSET: 4613 4614 Offset of the initial data structure in the memory 4615 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4616 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4617 data is located at the end of the available space 4618 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4619 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4620 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4621 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4622 4623 Note: 4624 On the MPC824X (or other systems that use the data 4625 cache for initial memory) the address chosen for 4626 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4627 point to an otherwise UNUSED address space between 4628 the top of RAM and the start of the PCI space. 4629 4630- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4631 4632- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4633 4634- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4635 4636- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4637 4638- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4639 4640- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4641 4642- CONFIG_SYS_OR_TIMING_SDRAM: 4643 SDRAM timing 4644 4645- CONFIG_SYS_MAMR_PTA: 4646 periodic timer for refresh 4647 4648- CONFIG_SYS_DER: Debug Event Register (37-47) 4649 4650- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4651 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4652 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4653 CONFIG_SYS_BR1_PRELIM: 4654 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4655 4656- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4657 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4658 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4659 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4660 4661- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4662 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4663 Machine Mode Register and Memory Periodic Timer 4664 Prescaler definitions (SDRAM timing) 4665 4666- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4667 enable I2C microcode relocation patch (MPC8xx); 4668 define relocation offset in DPRAM [DSP2] 4669 4670- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4671 enable SMC microcode relocation patch (MPC8xx); 4672 define relocation offset in DPRAM [SMC1] 4673 4674- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4675 enable SPI microcode relocation patch (MPC8xx); 4676 define relocation offset in DPRAM [SCC4] 4677 4678- CONFIG_SYS_USE_OSCCLK: 4679 Use OSCM clock mode on MBX8xx board. Be careful, 4680 wrong setting might damage your board. Read 4681 doc/README.MBX before setting this variable! 4682 4683- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4684 Offset of the bootmode word in DPRAM used by post 4685 (Power On Self Tests). This definition overrides 4686 #define'd default value in commproc.h resp. 4687 cpm_8260.h. 4688 4689- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4690 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4691 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4692 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4693 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4694 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4695 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4696 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4697 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4698 4699- CONFIG_PCI_DISABLE_PCIE: 4700 Disable PCI-Express on systems where it is supported but not 4701 required. 4702 4703- CONFIG_PCI_ENUM_ONLY 4704 Only scan through and get the devices on the buses. 4705 Don't do any setup work, presumably because someone or 4706 something has already done it, and we don't need to do it 4707 a second time. Useful for platforms that are pre-booted 4708 by coreboot or similar. 4709 4710- CONFIG_PCI_INDIRECT_BRIDGE: 4711 Enable support for indirect PCI bridges. 4712 4713- CONFIG_SYS_SRIO: 4714 Chip has SRIO or not 4715 4716- CONFIG_SRIO1: 4717 Board has SRIO 1 port available 4718 4719- CONFIG_SRIO2: 4720 Board has SRIO 2 port available 4721 4722- CONFIG_SRIO_PCIE_BOOT_MASTER 4723 Board can support master function for Boot from SRIO and PCIE 4724 4725- CONFIG_SYS_SRIOn_MEM_VIRT: 4726 Virtual Address of SRIO port 'n' memory region 4727 4728- CONFIG_SYS_SRIOn_MEM_PHYS: 4729 Physical Address of SRIO port 'n' memory region 4730 4731- CONFIG_SYS_SRIOn_MEM_SIZE: 4732 Size of SRIO port 'n' memory region 4733 4734- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4735 Defined to tell the NAND controller that the NAND chip is using 4736 a 16 bit bus. 4737 Not all NAND drivers use this symbol. 4738 Example of drivers that use it: 4739 - drivers/mtd/nand/ndfc.c 4740 - drivers/mtd/nand/mxc_nand.c 4741 4742- CONFIG_SYS_NDFC_EBC0_CFG 4743 Sets the EBC0_CFG register for the NDFC. If not defined 4744 a default value will be used. 4745 4746- CONFIG_SPD_EEPROM 4747 Get DDR timing information from an I2C EEPROM. Common 4748 with pluggable memory modules such as SODIMMs 4749 4750 SPD_EEPROM_ADDRESS 4751 I2C address of the SPD EEPROM 4752 4753- CONFIG_SYS_SPD_BUS_NUM 4754 If SPD EEPROM is on an I2C bus other than the first 4755 one, specify here. Note that the value must resolve 4756 to something your driver can deal with. 4757 4758- CONFIG_SYS_DDR_RAW_TIMING 4759 Get DDR timing information from other than SPD. Common with 4760 soldered DDR chips onboard without SPD. DDR raw timing 4761 parameters are extracted from datasheet and hard-coded into 4762 header files or board specific files. 4763 4764- CONFIG_FSL_DDR_INTERACTIVE 4765 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4766 4767- CONFIG_FSL_DDR_SYNC_REFRESH 4768 Enable sync of refresh for multiple controllers. 4769 4770- CONFIG_FSL_DDR_BIST 4771 Enable built-in memory test for Freescale DDR controllers. 4772 4773- CONFIG_SYS_83XX_DDR_USES_CS0 4774 Only for 83xx systems. If specified, then DDR should 4775 be configured using CS0 and CS1 instead of CS2 and CS3. 4776 4777- CONFIG_ETHER_ON_FEC[12] 4778 Define to enable FEC[12] on a 8xx series processor. 4779 4780- CONFIG_FEC[12]_PHY 4781 Define to the hardcoded PHY address which corresponds 4782 to the given FEC; i. e. 4783 #define CONFIG_FEC1_PHY 4 4784 means that the PHY with address 4 is connected to FEC1 4785 4786 When set to -1, means to probe for first available. 4787 4788- CONFIG_FEC[12]_PHY_NORXERR 4789 The PHY does not have a RXERR line (RMII only). 4790 (so program the FEC to ignore it). 4791 4792- CONFIG_RMII 4793 Enable RMII mode for all FECs. 4794 Note that this is a global option, we can't 4795 have one FEC in standard MII mode and another in RMII mode. 4796 4797- CONFIG_CRC32_VERIFY 4798 Add a verify option to the crc32 command. 4799 The syntax is: 4800 4801 => crc32 -v <address> <count> <crc32> 4802 4803 Where address/count indicate a memory area 4804 and crc32 is the correct crc32 which the 4805 area should have. 4806 4807- CONFIG_LOOPW 4808 Add the "loopw" memory command. This only takes effect if 4809 the memory commands are activated globally (CONFIG_CMD_MEM). 4810 4811- CONFIG_MX_CYCLIC 4812 Add the "mdc" and "mwc" memory commands. These are cyclic 4813 "md/mw" commands. 4814 Examples: 4815 4816 => mdc.b 10 4 500 4817 This command will print 4 bytes (10,11,12,13) each 500 ms. 4818 4819 => mwc.l 100 12345678 10 4820 This command will write 12345678 to address 100 all 10 ms. 4821 4822 This only takes effect if the memory commands are activated 4823 globally (CONFIG_CMD_MEM). 4824 4825- CONFIG_SKIP_LOWLEVEL_INIT 4826 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4827 low level initializations (like setting up the memory 4828 controller) are omitted and/or U-Boot does not 4829 relocate itself into RAM. 4830 4831 Normally this variable MUST NOT be defined. The only 4832 exception is when U-Boot is loaded (to RAM) by some 4833 other boot loader or by a debugger which performs 4834 these initializations itself. 4835 4836- CONFIG_SPL_BUILD 4837 Modifies the behaviour of start.S when compiling a loader 4838 that is executed before the actual U-Boot. E.g. when 4839 compiling a NAND SPL. 4840 4841- CONFIG_TPL_BUILD 4842 Modifies the behaviour of start.S when compiling a loader 4843 that is executed after the SPL and before the actual U-Boot. 4844 It is loaded by the SPL. 4845 4846- CONFIG_SYS_MPC85XX_NO_RESETVEC 4847 Only for 85xx systems. If this variable is specified, the section 4848 .resetvec is not kept and the section .bootpg is placed in the 4849 previous 4k of the .text section. 4850 4851- CONFIG_ARCH_MAP_SYSMEM 4852 Generally U-Boot (and in particular the md command) uses 4853 effective address. It is therefore not necessary to regard 4854 U-Boot address as virtual addresses that need to be translated 4855 to physical addresses. However, sandbox requires this, since 4856 it maintains its own little RAM buffer which contains all 4857 addressable memory. This option causes some memory accesses 4858 to be mapped through map_sysmem() / unmap_sysmem(). 4859 4860- CONFIG_USE_ARCH_MEMCPY 4861 CONFIG_USE_ARCH_MEMSET 4862 If these options are used a optimized version of memcpy/memset will 4863 be used if available. These functions may be faster under some 4864 conditions but may increase the binary size. 4865 4866- CONFIG_X86_RESET_VECTOR 4867 If defined, the x86 reset vector code is included. This is not 4868 needed when U-Boot is running from Coreboot. 4869 4870- CONFIG_SYS_MPUCLK 4871 Defines the MPU clock speed (in MHz). 4872 4873 NOTE : currently only supported on AM335x platforms. 4874 4875- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4876 Enables the RTC32K OSC on AM33xx based plattforms 4877 4878- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4879 Option to disable subpage write in NAND driver 4880 driver that uses this: 4881 drivers/mtd/nand/davinci_nand.c 4882 4883Freescale QE/FMAN Firmware Support: 4884----------------------------------- 4885 4886The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4887loading of "firmware", which is encoded in the QE firmware binary format. 4888This firmware often needs to be loaded during U-Boot booting, so macros 4889are used to identify the storage device (NOR flash, SPI, etc) and the address 4890within that device. 4891 4892- CONFIG_SYS_FMAN_FW_ADDR 4893 The address in the storage device where the FMAN microcode is located. The 4894 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4895 is also specified. 4896 4897- CONFIG_SYS_QE_FW_ADDR 4898 The address in the storage device where the QE microcode is located. The 4899 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4900 is also specified. 4901 4902- CONFIG_SYS_QE_FMAN_FW_LENGTH 4903 The maximum possible size of the firmware. The firmware binary format 4904 has a field that specifies the actual size of the firmware, but it 4905 might not be possible to read any part of the firmware unless some 4906 local storage is allocated to hold the entire firmware first. 4907 4908- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4909 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4910 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4911 virtual address in NOR flash. 4912 4913- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4914 Specifies that QE/FMAN firmware is located in NAND flash. 4915 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4916 4917- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4918 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4919 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4920 4921- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4922 Specifies that QE/FMAN firmware is located on the primary SPI 4923 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4924 4925- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4926 Specifies that QE/FMAN firmware is located in the remote (master) 4927 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4928 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4929 window->master inbound window->master LAW->the ucode address in 4930 master's memory space. 4931 4932Freescale Layerscape Management Complex Firmware Support: 4933--------------------------------------------------------- 4934The Freescale Layerscape Management Complex (MC) supports the loading of 4935"firmware". 4936This firmware often needs to be loaded during U-Boot booting, so macros 4937are used to identify the storage device (NOR flash, SPI, etc) and the address 4938within that device. 4939 4940- CONFIG_FSL_MC_ENET 4941 Enable the MC driver for Layerscape SoCs. 4942 4943- CONFIG_SYS_LS_MC_FW_ADDR 4944 The address in the storage device where the firmware is located. The 4945 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 4946 is also specified. 4947 4948- CONFIG_SYS_LS_MC_FW_LENGTH 4949 The maximum possible size of the firmware. The firmware binary format 4950 has a field that specifies the actual size of the firmware, but it 4951 might not be possible to read any part of the firmware unless some 4952 local storage is allocated to hold the entire firmware first. 4953 4954- CONFIG_SYS_LS_MC_FW_IN_NOR 4955 Specifies that MC firmware is located in NOR flash, mapped as 4956 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 4957 virtual address in NOR flash. 4958 4959Freescale Layerscape Debug Server Support: 4960------------------------------------------- 4961The Freescale Layerscape Debug Server Support supports the loading of 4962"Debug Server firmware" and triggering SP boot-rom. 4963This firmware often needs to be loaded during U-Boot booting. 4964 4965- CONFIG_FSL_DEBUG_SERVER 4966 Enable the Debug Server for Layerscape SoCs. 4967 4968- CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE 4969 Define minimum DDR size required for debug server image 4970 4971- CONFIG_SYS_MC_RSV_MEM_ALIGN 4972 Define alignment of reserved memory MC requires 4973 4974Reproducible builds 4975------------------- 4976 4977In order to achieve reproducible builds, timestamps used in the U-Boot build 4978process have to be set to a fixed value. 4979 4980This is done using the SOURCE_DATE_EPOCH environment variable. 4981SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4982option for U-Boot or an environment variable in U-Boot. 4983 4984SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4985 4986Building the Software: 4987====================== 4988 4989Building U-Boot has been tested in several native build environments 4990and in many different cross environments. Of course we cannot support 4991all possibly existing versions of cross development tools in all 4992(potentially obsolete) versions. In case of tool chain problems we 4993recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4994which is extensively used to build and test U-Boot. 4995 4996If you are not using a native environment, it is assumed that you 4997have GNU cross compiling tools available in your path. In this case, 4998you must set the environment variable CROSS_COMPILE in your shell. 4999Note that no changes to the Makefile or any other source files are 5000necessary. For example using the ELDK on a 4xx CPU, please enter: 5001 5002 $ CROSS_COMPILE=ppc_4xx- 5003 $ export CROSS_COMPILE 5004 5005Note: If you wish to generate Windows versions of the utilities in 5006 the tools directory you can use the MinGW toolchain 5007 (http://www.mingw.org). Set your HOST tools to the MinGW 5008 toolchain and execute 'make tools'. For example: 5009 5010 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5011 5012 Binaries such as tools/mkimage.exe will be created which can 5013 be executed on computers running Windows. 5014 5015U-Boot is intended to be simple to build. After installing the 5016sources you must configure U-Boot for one specific board type. This 5017is done by typing: 5018 5019 make NAME_defconfig 5020 5021where "NAME_defconfig" is the name of one of the existing configu- 5022rations; see boards.cfg for supported names. 5023 5024Note: for some board special configuration names may exist; check if 5025 additional information is available from the board vendor; for 5026 instance, the TQM823L systems are available without (standard) 5027 or with LCD support. You can select such additional "features" 5028 when choosing the configuration, i. e. 5029 5030 make TQM823L_defconfig 5031 - will configure for a plain TQM823L, i. e. no LCD support 5032 5033 make TQM823L_LCD_defconfig 5034 - will configure for a TQM823L with U-Boot console on LCD 5035 5036 etc. 5037 5038 5039Finally, type "make all", and you should get some working U-Boot 5040images ready for download to / installation on your system: 5041 5042- "u-boot.bin" is a raw binary image 5043- "u-boot" is an image in ELF binary format 5044- "u-boot.srec" is in Motorola S-Record format 5045 5046By default the build is performed locally and the objects are saved 5047in the source directory. One of the two methods can be used to change 5048this behavior and build U-Boot to some external directory: 5049 50501. Add O= to the make command line invocations: 5051 5052 make O=/tmp/build distclean 5053 make O=/tmp/build NAME_defconfig 5054 make O=/tmp/build all 5055 50562. Set environment variable KBUILD_OUTPUT to point to the desired location: 5057 5058 export KBUILD_OUTPUT=/tmp/build 5059 make distclean 5060 make NAME_defconfig 5061 make all 5062 5063Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5064variable. 5065 5066 5067Please be aware that the Makefiles assume you are using GNU make, so 5068for instance on NetBSD you might need to use "gmake" instead of 5069native "make". 5070 5071 5072If the system board that you have is not listed, then you will need 5073to port U-Boot to your hardware platform. To do this, follow these 5074steps: 5075 50761. Create a new directory to hold your board specific code. Add any 5077 files you need. In your board directory, you will need at least 5078 the "Makefile" and a "<board>.c". 50792. Create a new configuration file "include/configs/<board>.h" for 5080 your board. 50813. If you're porting U-Boot to a new CPU, then also create a new 5082 directory to hold your CPU specific code. Add any files you need. 50834. Run "make <board>_defconfig" with your new name. 50845. Type "make", and you should get a working "u-boot.srec" file 5085 to be installed on your target system. 50866. Debug and solve any problems that might arise. 5087 [Of course, this last step is much harder than it sounds.] 5088 5089 5090Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5091============================================================== 5092 5093If you have modified U-Boot sources (for instance added a new board 5094or support for new devices, a new CPU, etc.) you are expected to 5095provide feedback to the other developers. The feedback normally takes 5096the form of a "patch", i. e. a context diff against a certain (latest 5097official or latest in the git repository) version of U-Boot sources. 5098 5099But before you submit such a patch, please verify that your modifi- 5100cation did not break existing code. At least make sure that *ALL* of 5101the supported boards compile WITHOUT ANY compiler warnings. To do so, 5102just run the "MAKEALL" script, which will configure and build U-Boot 5103for ALL supported system. Be warned, this will take a while. You can 5104select which (cross) compiler to use by passing a `CROSS_COMPILE' 5105environment variable to the script, i. e. to use the ELDK cross tools 5106you can type 5107 5108 CROSS_COMPILE=ppc_8xx- MAKEALL 5109 5110or to build on a native PowerPC system you can type 5111 5112 CROSS_COMPILE=' ' MAKEALL 5113 5114When using the MAKEALL script, the default behaviour is to build 5115U-Boot in the source directory. This location can be changed by 5116setting the BUILD_DIR environment variable. Also, for each target 5117built, the MAKEALL script saves two log files (<target>.ERR and 5118<target>.MAKEALL) in the <source dir>/LOG directory. This default 5119location can be changed by setting the MAKEALL_LOGDIR environment 5120variable. For example: 5121 5122 export BUILD_DIR=/tmp/build 5123 export MAKEALL_LOGDIR=/tmp/log 5124 CROSS_COMPILE=ppc_8xx- MAKEALL 5125 5126With the above settings build objects are saved in the /tmp/build, 5127log files are saved in the /tmp/log and the source tree remains clean 5128during the whole build process. 5129 5130 5131See also "U-Boot Porting Guide" below. 5132 5133 5134Monitor Commands - Overview: 5135============================ 5136 5137go - start application at address 'addr' 5138run - run commands in an environment variable 5139bootm - boot application image from memory 5140bootp - boot image via network using BootP/TFTP protocol 5141bootz - boot zImage from memory 5142tftpboot- boot image via network using TFTP protocol 5143 and env variables "ipaddr" and "serverip" 5144 (and eventually "gatewayip") 5145tftpput - upload a file via network using TFTP protocol 5146rarpboot- boot image via network using RARP/TFTP protocol 5147diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5148loads - load S-Record file over serial line 5149loadb - load binary file over serial line (kermit mode) 5150md - memory display 5151mm - memory modify (auto-incrementing) 5152nm - memory modify (constant address) 5153mw - memory write (fill) 5154cp - memory copy 5155cmp - memory compare 5156crc32 - checksum calculation 5157i2c - I2C sub-system 5158sspi - SPI utility commands 5159base - print or set address offset 5160printenv- print environment variables 5161setenv - set environment variables 5162saveenv - save environment variables to persistent storage 5163protect - enable or disable FLASH write protection 5164erase - erase FLASH memory 5165flinfo - print FLASH memory information 5166nand - NAND memory operations (see doc/README.nand) 5167bdinfo - print Board Info structure 5168iminfo - print header information for application image 5169coninfo - print console devices and informations 5170ide - IDE sub-system 5171loop - infinite loop on address range 5172loopw - infinite write loop on address range 5173mtest - simple RAM test 5174icache - enable or disable instruction cache 5175dcache - enable or disable data cache 5176reset - Perform RESET of the CPU 5177echo - echo args to console 5178version - print monitor version 5179help - print online help 5180? - alias for 'help' 5181 5182 5183Monitor Commands - Detailed Description: 5184======================================== 5185 5186TODO. 5187 5188For now: just type "help <command>". 5189 5190 5191Environment Variables: 5192====================== 5193 5194U-Boot supports user configuration using Environment Variables which 5195can be made persistent by saving to Flash memory. 5196 5197Environment Variables are set using "setenv", printed using 5198"printenv", and saved to Flash using "saveenv". Using "setenv" 5199without a value can be used to delete a variable from the 5200environment. As long as you don't save the environment you are 5201working with an in-memory copy. In case the Flash area containing the 5202environment is erased by accident, a default environment is provided. 5203 5204Some configuration options can be set using Environment Variables. 5205 5206List of environment variables (most likely not complete): 5207 5208 baudrate - see CONFIG_BAUDRATE 5209 5210 bootdelay - see CONFIG_BOOTDELAY 5211 5212 bootcmd - see CONFIG_BOOTCOMMAND 5213 5214 bootargs - Boot arguments when booting an RTOS image 5215 5216 bootfile - Name of the image to load with TFTP 5217 5218 bootm_low - Memory range available for image processing in the bootm 5219 command can be restricted. This variable is given as 5220 a hexadecimal number and defines lowest address allowed 5221 for use by the bootm command. See also "bootm_size" 5222 environment variable. Address defined by "bootm_low" is 5223 also the base of the initial memory mapping for the Linux 5224 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5225 bootm_mapsize. 5226 5227 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5228 This variable is given as a hexadecimal number and it 5229 defines the size of the memory region starting at base 5230 address bootm_low that is accessible by the Linux kernel 5231 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5232 as the default value if it is defined, and bootm_size is 5233 used otherwise. 5234 5235 bootm_size - Memory range available for image processing in the bootm 5236 command can be restricted. This variable is given as 5237 a hexadecimal number and defines the size of the region 5238 allowed for use by the bootm command. See also "bootm_low" 5239 environment variable. 5240 5241 updatefile - Location of the software update file on a TFTP server, used 5242 by the automatic software update feature. Please refer to 5243 documentation in doc/README.update for more details. 5244 5245 autoload - if set to "no" (any string beginning with 'n'), 5246 "bootp" will just load perform a lookup of the 5247 configuration from the BOOTP server, but not try to 5248 load any image using TFTP 5249 5250 autostart - if set to "yes", an image loaded using the "bootp", 5251 "rarpboot", "tftpboot" or "diskboot" commands will 5252 be automatically started (by internally calling 5253 "bootm") 5254 5255 If set to "no", a standalone image passed to the 5256 "bootm" command will be copied to the load address 5257 (and eventually uncompressed), but NOT be started. 5258 This can be used to load and uncompress arbitrary 5259 data. 5260 5261 fdt_high - if set this restricts the maximum address that the 5262 flattened device tree will be copied into upon boot. 5263 For example, if you have a system with 1 GB memory 5264 at physical address 0x10000000, while Linux kernel 5265 only recognizes the first 704 MB as low memory, you 5266 may need to set fdt_high as 0x3C000000 to have the 5267 device tree blob be copied to the maximum address 5268 of the 704 MB low memory, so that Linux kernel can 5269 access it during the boot procedure. 5270 5271 If this is set to the special value 0xFFFFFFFF then 5272 the fdt will not be copied at all on boot. For this 5273 to work it must reside in writable memory, have 5274 sufficient padding on the end of it for u-boot to 5275 add the information it needs into it, and the memory 5276 must be accessible by the kernel. 5277 5278 fdtcontroladdr- if set this is the address of the control flattened 5279 device tree used by U-Boot when CONFIG_OF_CONTROL is 5280 defined. 5281 5282 i2cfast - (PPC405GP|PPC405EP only) 5283 if set to 'y' configures Linux I2C driver for fast 5284 mode (400kHZ). This environment variable is used in 5285 initialization code. So, for changes to be effective 5286 it must be saved and board must be reset. 5287 5288 initrd_high - restrict positioning of initrd images: 5289 If this variable is not set, initrd images will be 5290 copied to the highest possible address in RAM; this 5291 is usually what you want since it allows for 5292 maximum initrd size. If for some reason you want to 5293 make sure that the initrd image is loaded below the 5294 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5295 variable to a value of "no" or "off" or "0". 5296 Alternatively, you can set it to a maximum upper 5297 address to use (U-Boot will still check that it 5298 does not overwrite the U-Boot stack and data). 5299 5300 For instance, when you have a system with 16 MB 5301 RAM, and want to reserve 4 MB from use by Linux, 5302 you can do this by adding "mem=12M" to the value of 5303 the "bootargs" variable. However, now you must make 5304 sure that the initrd image is placed in the first 5305 12 MB as well - this can be done with 5306 5307 setenv initrd_high 00c00000 5308 5309 If you set initrd_high to 0xFFFFFFFF, this is an 5310 indication to U-Boot that all addresses are legal 5311 for the Linux kernel, including addresses in flash 5312 memory. In this case U-Boot will NOT COPY the 5313 ramdisk at all. This may be useful to reduce the 5314 boot time on your system, but requires that this 5315 feature is supported by your Linux kernel. 5316 5317 ipaddr - IP address; needed for tftpboot command 5318 5319 loadaddr - Default load address for commands like "bootp", 5320 "rarpboot", "tftpboot", "loadb" or "diskboot" 5321 5322 loads_echo - see CONFIG_LOADS_ECHO 5323 5324 serverip - TFTP server IP address; needed for tftpboot command 5325 5326 bootretry - see CONFIG_BOOT_RETRY_TIME 5327 5328 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5329 5330 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5331 5332 ethprime - controls which interface is used first. 5333 5334 ethact - controls which interface is currently active. 5335 For example you can do the following 5336 5337 => setenv ethact FEC 5338 => ping 192.168.0.1 # traffic sent on FEC 5339 => setenv ethact SCC 5340 => ping 10.0.0.1 # traffic sent on SCC 5341 5342 ethrotate - When set to "no" U-Boot does not go through all 5343 available network interfaces. 5344 It just stays at the currently selected interface. 5345 5346 netretry - When set to "no" each network operation will 5347 either succeed or fail without retrying. 5348 When set to "once" the network operation will 5349 fail when all the available network interfaces 5350 are tried once without success. 5351 Useful on scripts which control the retry operation 5352 themselves. 5353 5354 npe_ucode - set load address for the NPE microcode 5355 5356 silent_linux - If set then Linux will be told to boot silently, by 5357 changing the console to be empty. If "yes" it will be 5358 made silent. If "no" it will not be made silent. If 5359 unset, then it will be made silent if the U-Boot console 5360 is silent. 5361 5362 tftpsrcp - If this is set, the value is used for TFTP's 5363 UDP source port. 5364 5365 tftpdstp - If this is set, the value is used for TFTP's UDP 5366 destination port instead of the Well Know Port 69. 5367 5368 tftpblocksize - Block size to use for TFTP transfers; if not set, 5369 we use the TFTP server's default block size 5370 5371 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5372 seconds, minimum value is 1000 = 1 second). Defines 5373 when a packet is considered to be lost so it has to 5374 be retransmitted. The default is 5000 = 5 seconds. 5375 Lowering this value may make downloads succeed 5376 faster in networks with high packet loss rates or 5377 with unreliable TFTP servers. 5378 5379 tftptimeoutcountmax - maximum count of TFTP timeouts (no 5380 unit, minimum value = 0). Defines how many timeouts 5381 can happen during a single file transfer before that 5382 transfer is aborted. The default is 10, and 0 means 5383 'no timeouts allowed'. Increasing this value may help 5384 downloads succeed with high packet loss rates, or with 5385 unreliable TFTP servers or client hardware. 5386 5387 vlan - When set to a value < 4095 the traffic over 5388 Ethernet is encapsulated/received over 802.1q 5389 VLAN tagged frames. 5390 5391 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 5392 Unsigned value, in milliseconds. If not set, the period will 5393 be either the default (28000), or a value based on 5394 CONFIG_NET_RETRY_COUNT, if defined. This value has 5395 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 5396 5397The following image location variables contain the location of images 5398used in booting. The "Image" column gives the role of the image and is 5399not an environment variable name. The other columns are environment 5400variable names. "File Name" gives the name of the file on a TFTP 5401server, "RAM Address" gives the location in RAM the image will be 5402loaded to, and "Flash Location" gives the image's address in NOR 5403flash or offset in NAND flash. 5404 5405*Note* - these variables don't have to be defined for all boards, some 5406boards currently use other variables for these purposes, and some 5407boards use these variables for other purposes. 5408 5409Image File Name RAM Address Flash Location 5410----- --------- ----------- -------------- 5411u-boot u-boot u-boot_addr_r u-boot_addr 5412Linux kernel bootfile kernel_addr_r kernel_addr 5413device tree blob fdtfile fdt_addr_r fdt_addr 5414ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5415 5416The following environment variables may be used and automatically 5417updated by the network boot commands ("bootp" and "rarpboot"), 5418depending the information provided by your boot server: 5419 5420 bootfile - see above 5421 dnsip - IP address of your Domain Name Server 5422 dnsip2 - IP address of your secondary Domain Name Server 5423 gatewayip - IP address of the Gateway (Router) to use 5424 hostname - Target hostname 5425 ipaddr - see above 5426 netmask - Subnet Mask 5427 rootpath - Pathname of the root filesystem on the NFS server 5428 serverip - see above 5429 5430 5431There are two special Environment Variables: 5432 5433 serial# - contains hardware identification information such 5434 as type string and/or serial number 5435 ethaddr - Ethernet address 5436 5437These variables can be set only once (usually during manufacturing of 5438the board). U-Boot refuses to delete or overwrite these variables 5439once they have been set once. 5440 5441 5442Further special Environment Variables: 5443 5444 ver - Contains the U-Boot version string as printed 5445 with the "version" command. This variable is 5446 readonly (see CONFIG_VERSION_VARIABLE). 5447 5448 5449Please note that changes to some configuration parameters may take 5450only effect after the next boot (yes, that's just like Windoze :-). 5451 5452 5453Callback functions for environment variables: 5454--------------------------------------------- 5455 5456For some environment variables, the behavior of u-boot needs to change 5457when their values are changed. This functionality allows functions to 5458be associated with arbitrary variables. On creation, overwrite, or 5459deletion, the callback will provide the opportunity for some side 5460effect to happen or for the change to be rejected. 5461 5462The callbacks are named and associated with a function using the 5463U_BOOT_ENV_CALLBACK macro in your board or driver code. 5464 5465These callbacks are associated with variables in one of two ways. The 5466static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5467in the board configuration to a string that defines a list of 5468associations. The list must be in the following format: 5469 5470 entry = variable_name[:callback_name] 5471 list = entry[,list] 5472 5473If the callback name is not specified, then the callback is deleted. 5474Spaces are also allowed anywhere in the list. 5475 5476Callbacks can also be associated by defining the ".callbacks" variable 5477with the same list format above. Any association in ".callbacks" will 5478override any association in the static list. You can define 5479CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5480".callbacks" environment variable in the default or embedded environment. 5481 5482If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5483regular expression. This allows multiple variables to be connected to 5484the same callback without explicitly listing them all out. 5485 5486 5487Command Line Parsing: 5488===================== 5489 5490There are two different command line parsers available with U-Boot: 5491the old "simple" one, and the much more powerful "hush" shell: 5492 5493Old, simple command line parser: 5494-------------------------------- 5495 5496- supports environment variables (through setenv / saveenv commands) 5497- several commands on one line, separated by ';' 5498- variable substitution using "... ${name} ..." syntax 5499- special characters ('$', ';') can be escaped by prefixing with '\', 5500 for example: 5501 setenv bootcmd bootm \${address} 5502- You can also escape text by enclosing in single apostrophes, for example: 5503 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5504 5505Hush shell: 5506----------- 5507 5508- similar to Bourne shell, with control structures like 5509 if...then...else...fi, for...do...done; while...do...done, 5510 until...do...done, ... 5511- supports environment ("global") variables (through setenv / saveenv 5512 commands) and local shell variables (through standard shell syntax 5513 "name=value"); only environment variables can be used with "run" 5514 command 5515 5516General rules: 5517-------------- 5518 5519(1) If a command line (or an environment variable executed by a "run" 5520 command) contains several commands separated by semicolon, and 5521 one of these commands fails, then the remaining commands will be 5522 executed anyway. 5523 5524(2) If you execute several variables with one call to run (i. e. 5525 calling run with a list of variables as arguments), any failing 5526 command will cause "run" to terminate, i. e. the remaining 5527 variables are not executed. 5528 5529Note for Redundant Ethernet Interfaces: 5530======================================= 5531 5532Some boards come with redundant Ethernet interfaces; U-Boot supports 5533such configurations and is capable of automatic selection of a 5534"working" interface when needed. MAC assignment works as follows: 5535 5536Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5537MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5538"eth1addr" (=>eth1), "eth2addr", ... 5539 5540If the network interface stores some valid MAC address (for instance 5541in SROM), this is used as default address if there is NO correspon- 5542ding setting in the environment; if the corresponding environment 5543variable is set, this overrides the settings in the card; that means: 5544 5545o If the SROM has a valid MAC address, and there is no address in the 5546 environment, the SROM's address is used. 5547 5548o If there is no valid address in the SROM, and a definition in the 5549 environment exists, then the value from the environment variable is 5550 used. 5551 5552o If both the SROM and the environment contain a MAC address, and 5553 both addresses are the same, this MAC address is used. 5554 5555o If both the SROM and the environment contain a MAC address, and the 5556 addresses differ, the value from the environment is used and a 5557 warning is printed. 5558 5559o If neither SROM nor the environment contain a MAC address, an error 5560 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5561 a random, locally-assigned MAC is used. 5562 5563If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5564will be programmed into hardware as part of the initialization process. This 5565may be skipped by setting the appropriate 'ethmacskip' environment variable. 5566The naming convention is as follows: 5567"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5568 5569Image Formats: 5570============== 5571 5572U-Boot is capable of booting (and performing other auxiliary operations on) 5573images in two formats: 5574 5575New uImage format (FIT) 5576----------------------- 5577 5578Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5579to Flattened Device Tree). It allows the use of images with multiple 5580components (several kernels, ramdisks, etc.), with contents protected by 5581SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5582 5583 5584Old uImage format 5585----------------- 5586 5587Old image format is based on binary files which can be basically anything, 5588preceded by a special header; see the definitions in include/image.h for 5589details; basically, the header defines the following image properties: 5590 5591* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5592 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5593 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5594 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5595 INTEGRITY). 5596* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5597 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5598 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5599* Compression Type (uncompressed, gzip, bzip2) 5600* Load Address 5601* Entry Point 5602* Image Name 5603* Image Timestamp 5604 5605The header is marked by a special Magic Number, and both the header 5606and the data portions of the image are secured against corruption by 5607CRC32 checksums. 5608 5609 5610Linux Support: 5611============== 5612 5613Although U-Boot should support any OS or standalone application 5614easily, the main focus has always been on Linux during the design of 5615U-Boot. 5616 5617U-Boot includes many features that so far have been part of some 5618special "boot loader" code within the Linux kernel. Also, any 5619"initrd" images to be used are no longer part of one big Linux image; 5620instead, kernel and "initrd" are separate images. This implementation 5621serves several purposes: 5622 5623- the same features can be used for other OS or standalone 5624 applications (for instance: using compressed images to reduce the 5625 Flash memory footprint) 5626 5627- it becomes much easier to port new Linux kernel versions because 5628 lots of low-level, hardware dependent stuff are done by U-Boot 5629 5630- the same Linux kernel image can now be used with different "initrd" 5631 images; of course this also means that different kernel images can 5632 be run with the same "initrd". This makes testing easier (you don't 5633 have to build a new "zImage.initrd" Linux image when you just 5634 change a file in your "initrd"). Also, a field-upgrade of the 5635 software is easier now. 5636 5637 5638Linux HOWTO: 5639============ 5640 5641Porting Linux to U-Boot based systems: 5642--------------------------------------- 5643 5644U-Boot cannot save you from doing all the necessary modifications to 5645configure the Linux device drivers for use with your target hardware 5646(no, we don't intend to provide a full virtual machine interface to 5647Linux :-). 5648 5649But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5650 5651Just make sure your machine specific header file (for instance 5652include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5653Information structure as we define in include/asm-<arch>/u-boot.h, 5654and make sure that your definition of IMAP_ADDR uses the same value 5655as your U-Boot configuration in CONFIG_SYS_IMMR. 5656 5657Note that U-Boot now has a driver model, a unified model for drivers. 5658If you are adding a new driver, plumb it into driver model. If there 5659is no uclass available, you are encouraged to create one. See 5660doc/driver-model. 5661 5662 5663Configuring the Linux kernel: 5664----------------------------- 5665 5666No specific requirements for U-Boot. Make sure you have some root 5667device (initial ramdisk, NFS) for your target system. 5668 5669 5670Building a Linux Image: 5671----------------------- 5672 5673With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5674not used. If you use recent kernel source, a new build target 5675"uImage" will exist which automatically builds an image usable by 5676U-Boot. Most older kernels also have support for a "pImage" target, 5677which was introduced for our predecessor project PPCBoot and uses a 5678100% compatible format. 5679 5680Example: 5681 5682 make TQM850L_defconfig 5683 make oldconfig 5684 make dep 5685 make uImage 5686 5687The "uImage" build target uses a special tool (in 'tools/mkimage') to 5688encapsulate a compressed Linux kernel image with header information, 5689CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5690 5691* build a standard "vmlinux" kernel image (in ELF binary format): 5692 5693* convert the kernel into a raw binary image: 5694 5695 ${CROSS_COMPILE}-objcopy -O binary \ 5696 -R .note -R .comment \ 5697 -S vmlinux linux.bin 5698 5699* compress the binary image: 5700 5701 gzip -9 linux.bin 5702 5703* package compressed binary image for U-Boot: 5704 5705 mkimage -A ppc -O linux -T kernel -C gzip \ 5706 -a 0 -e 0 -n "Linux Kernel Image" \ 5707 -d linux.bin.gz uImage 5708 5709 5710The "mkimage" tool can also be used to create ramdisk images for use 5711with U-Boot, either separated from the Linux kernel image, or 5712combined into one file. "mkimage" encapsulates the images with a 64 5713byte header containing information about target architecture, 5714operating system, image type, compression method, entry points, time 5715stamp, CRC32 checksums, etc. 5716 5717"mkimage" can be called in two ways: to verify existing images and 5718print the header information, or to build new images. 5719 5720In the first form (with "-l" option) mkimage lists the information 5721contained in the header of an existing U-Boot image; this includes 5722checksum verification: 5723 5724 tools/mkimage -l image 5725 -l ==> list image header information 5726 5727The second form (with "-d" option) is used to build a U-Boot image 5728from a "data file" which is used as image payload: 5729 5730 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5731 -n name -d data_file image 5732 -A ==> set architecture to 'arch' 5733 -O ==> set operating system to 'os' 5734 -T ==> set image type to 'type' 5735 -C ==> set compression type 'comp' 5736 -a ==> set load address to 'addr' (hex) 5737 -e ==> set entry point to 'ep' (hex) 5738 -n ==> set image name to 'name' 5739 -d ==> use image data from 'datafile' 5740 5741Right now, all Linux kernels for PowerPC systems use the same load 5742address (0x00000000), but the entry point address depends on the 5743kernel version: 5744 5745- 2.2.x kernels have the entry point at 0x0000000C, 5746- 2.3.x and later kernels have the entry point at 0x00000000. 5747 5748So a typical call to build a U-Boot image would read: 5749 5750 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5751 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5752 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5753 > examples/uImage.TQM850L 5754 Image Name: 2.4.4 kernel for TQM850L 5755 Created: Wed Jul 19 02:34:59 2000 5756 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5757 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5758 Load Address: 0x00000000 5759 Entry Point: 0x00000000 5760 5761To verify the contents of the image (or check for corruption): 5762 5763 -> tools/mkimage -l examples/uImage.TQM850L 5764 Image Name: 2.4.4 kernel for TQM850L 5765 Created: Wed Jul 19 02:34:59 2000 5766 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5767 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5768 Load Address: 0x00000000 5769 Entry Point: 0x00000000 5770 5771NOTE: for embedded systems where boot time is critical you can trade 5772speed for memory and install an UNCOMPRESSED image instead: this 5773needs more space in Flash, but boots much faster since it does not 5774need to be uncompressed: 5775 5776 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5777 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5778 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5779 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5780 > examples/uImage.TQM850L-uncompressed 5781 Image Name: 2.4.4 kernel for TQM850L 5782 Created: Wed Jul 19 02:34:59 2000 5783 Image Type: PowerPC Linux Kernel Image (uncompressed) 5784 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5785 Load Address: 0x00000000 5786 Entry Point: 0x00000000 5787 5788 5789Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5790when your kernel is intended to use an initial ramdisk: 5791 5792 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5793 > -A ppc -O linux -T ramdisk -C gzip \ 5794 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5795 Image Name: Simple Ramdisk Image 5796 Created: Wed Jan 12 14:01:50 2000 5797 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5798 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5799 Load Address: 0x00000000 5800 Entry Point: 0x00000000 5801 5802The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5803option performs the converse operation of the mkimage's second form (the "-d" 5804option). Given an image built by mkimage, the dumpimage extracts a "data file" 5805from the image: 5806 5807 tools/dumpimage -i image -T type -p position data_file 5808 -i ==> extract from the 'image' a specific 'data_file' 5809 -T ==> set image type to 'type' 5810 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5811 5812 5813Installing a Linux Image: 5814------------------------- 5815 5816To downloading a U-Boot image over the serial (console) interface, 5817you must convert the image to S-Record format: 5818 5819 objcopy -I binary -O srec examples/image examples/image.srec 5820 5821The 'objcopy' does not understand the information in the U-Boot 5822image header, so the resulting S-Record file will be relative to 5823address 0x00000000. To load it to a given address, you need to 5824specify the target address as 'offset' parameter with the 'loads' 5825command. 5826 5827Example: install the image to address 0x40100000 (which on the 5828TQM8xxL is in the first Flash bank): 5829 5830 => erase 40100000 401FFFFF 5831 5832 .......... done 5833 Erased 8 sectors 5834 5835 => loads 40100000 5836 ## Ready for S-Record download ... 5837 ~>examples/image.srec 5838 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5839 ... 5840 15989 15990 15991 15992 5841 [file transfer complete] 5842 [connected] 5843 ## Start Addr = 0x00000000 5844 5845 5846You can check the success of the download using the 'iminfo' command; 5847this includes a checksum verification so you can be sure no data 5848corruption happened: 5849 5850 => imi 40100000 5851 5852 ## Checking Image at 40100000 ... 5853 Image Name: 2.2.13 for initrd on TQM850L 5854 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5855 Data Size: 335725 Bytes = 327 kB = 0 MB 5856 Load Address: 00000000 5857 Entry Point: 0000000c 5858 Verifying Checksum ... OK 5859 5860 5861Boot Linux: 5862----------- 5863 5864The "bootm" command is used to boot an application that is stored in 5865memory (RAM or Flash). In case of a Linux kernel image, the contents 5866of the "bootargs" environment variable is passed to the kernel as 5867parameters. You can check and modify this variable using the 5868"printenv" and "setenv" commands: 5869 5870 5871 => printenv bootargs 5872 bootargs=root=/dev/ram 5873 5874 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5875 5876 => printenv bootargs 5877 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5878 5879 => bootm 40020000 5880 ## Booting Linux kernel at 40020000 ... 5881 Image Name: 2.2.13 for NFS on TQM850L 5882 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5883 Data Size: 381681 Bytes = 372 kB = 0 MB 5884 Load Address: 00000000 5885 Entry Point: 0000000c 5886 Verifying Checksum ... OK 5887 Uncompressing Kernel Image ... OK 5888 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 5889 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5890 time_init: decrementer frequency = 187500000/60 5891 Calibrating delay loop... 49.77 BogoMIPS 5892 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5893 ... 5894 5895If you want to boot a Linux kernel with initial RAM disk, you pass 5896the memory addresses of both the kernel and the initrd image (PPBCOOT 5897format!) to the "bootm" command: 5898 5899 => imi 40100000 40200000 5900 5901 ## Checking Image at 40100000 ... 5902 Image Name: 2.2.13 for initrd on TQM850L 5903 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5904 Data Size: 335725 Bytes = 327 kB = 0 MB 5905 Load Address: 00000000 5906 Entry Point: 0000000c 5907 Verifying Checksum ... OK 5908 5909 ## Checking Image at 40200000 ... 5910 Image Name: Simple Ramdisk Image 5911 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5912 Data Size: 566530 Bytes = 553 kB = 0 MB 5913 Load Address: 00000000 5914 Entry Point: 00000000 5915 Verifying Checksum ... OK 5916 5917 => bootm 40100000 40200000 5918 ## Booting Linux kernel at 40100000 ... 5919 Image Name: 2.2.13 for initrd on TQM850L 5920 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5921 Data Size: 335725 Bytes = 327 kB = 0 MB 5922 Load Address: 00000000 5923 Entry Point: 0000000c 5924 Verifying Checksum ... OK 5925 Uncompressing Kernel Image ... OK 5926 ## Loading RAMDisk Image at 40200000 ... 5927 Image Name: Simple Ramdisk Image 5928 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5929 Data Size: 566530 Bytes = 553 kB = 0 MB 5930 Load Address: 00000000 5931 Entry Point: 00000000 5932 Verifying Checksum ... OK 5933 Loading Ramdisk ... OK 5934 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 5935 Boot arguments: root=/dev/ram 5936 time_init: decrementer frequency = 187500000/60 5937 Calibrating delay loop... 49.77 BogoMIPS 5938 ... 5939 RAMDISK: Compressed image found at block 0 5940 VFS: Mounted root (ext2 filesystem). 5941 5942 bash# 5943 5944Boot Linux and pass a flat device tree: 5945----------- 5946 5947First, U-Boot must be compiled with the appropriate defines. See the section 5948titled "Linux Kernel Interface" above for a more in depth explanation. The 5949following is an example of how to start a kernel and pass an updated 5950flat device tree: 5951 5952=> print oftaddr 5953oftaddr=0x300000 5954=> print oft 5955oft=oftrees/mpc8540ads.dtb 5956=> tftp $oftaddr $oft 5957Speed: 1000, full duplex 5958Using TSEC0 device 5959TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5960Filename 'oftrees/mpc8540ads.dtb'. 5961Load address: 0x300000 5962Loading: # 5963done 5964Bytes transferred = 4106 (100a hex) 5965=> tftp $loadaddr $bootfile 5966Speed: 1000, full duplex 5967Using TSEC0 device 5968TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5969Filename 'uImage'. 5970Load address: 0x200000 5971Loading:############ 5972done 5973Bytes transferred = 1029407 (fb51f hex) 5974=> print loadaddr 5975loadaddr=200000 5976=> print oftaddr 5977oftaddr=0x300000 5978=> bootm $loadaddr - $oftaddr 5979## Booting image at 00200000 ... 5980 Image Name: Linux-2.6.17-dirty 5981 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5982 Data Size: 1029343 Bytes = 1005.2 kB 5983 Load Address: 00000000 5984 Entry Point: 00000000 5985 Verifying Checksum ... OK 5986 Uncompressing Kernel Image ... OK 5987Booting using flat device tree at 0x300000 5988Using MPC85xx ADS machine description 5989Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5990[snip] 5991 5992 5993More About U-Boot Image Types: 5994------------------------------ 5995 5996U-Boot supports the following image types: 5997 5998 "Standalone Programs" are directly runnable in the environment 5999 provided by U-Boot; it is expected that (if they behave 6000 well) you can continue to work in U-Boot after return from 6001 the Standalone Program. 6002 "OS Kernel Images" are usually images of some Embedded OS which 6003 will take over control completely. Usually these programs 6004 will install their own set of exception handlers, device 6005 drivers, set up the MMU, etc. - this means, that you cannot 6006 expect to re-enter U-Boot except by resetting the CPU. 6007 "RAMDisk Images" are more or less just data blocks, and their 6008 parameters (address, size) are passed to an OS kernel that is 6009 being started. 6010 "Multi-File Images" contain several images, typically an OS 6011 (Linux) kernel image and one or more data images like 6012 RAMDisks. This construct is useful for instance when you want 6013 to boot over the network using BOOTP etc., where the boot 6014 server provides just a single image file, but you want to get 6015 for instance an OS kernel and a RAMDisk image. 6016 6017 "Multi-File Images" start with a list of image sizes, each 6018 image size (in bytes) specified by an "uint32_t" in network 6019 byte order. This list is terminated by an "(uint32_t)0". 6020 Immediately after the terminating 0 follow the images, one by 6021 one, all aligned on "uint32_t" boundaries (size rounded up to 6022 a multiple of 4 bytes). 6023 6024 "Firmware Images" are binary images containing firmware (like 6025 U-Boot or FPGA images) which usually will be programmed to 6026 flash memory. 6027 6028 "Script files" are command sequences that will be executed by 6029 U-Boot's command interpreter; this feature is especially 6030 useful when you configure U-Boot to use a real shell (hush) 6031 as command interpreter. 6032 6033Booting the Linux zImage: 6034------------------------- 6035 6036On some platforms, it's possible to boot Linux zImage. This is done 6037using the "bootz" command. The syntax of "bootz" command is the same 6038as the syntax of "bootm" command. 6039 6040Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6041kernel with raw initrd images. The syntax is slightly different, the 6042address of the initrd must be augmented by it's size, in the following 6043format: "<initrd addres>:<initrd size>". 6044 6045 6046Standalone HOWTO: 6047================= 6048 6049One of the features of U-Boot is that you can dynamically load and 6050run "standalone" applications, which can use some resources of 6051U-Boot like console I/O functions or interrupt services. 6052 6053Two simple examples are included with the sources: 6054 6055"Hello World" Demo: 6056------------------- 6057 6058'examples/hello_world.c' contains a small "Hello World" Demo 6059application; it is automatically compiled when you build U-Boot. 6060It's configured to run at address 0x00040004, so you can play with it 6061like that: 6062 6063 => loads 6064 ## Ready for S-Record download ... 6065 ~>examples/hello_world.srec 6066 1 2 3 4 5 6 7 8 9 10 11 ... 6067 [file transfer complete] 6068 [connected] 6069 ## Start Addr = 0x00040004 6070 6071 => go 40004 Hello World! This is a test. 6072 ## Starting application at 0x00040004 ... 6073 Hello World 6074 argc = 7 6075 argv[0] = "40004" 6076 argv[1] = "Hello" 6077 argv[2] = "World!" 6078 argv[3] = "This" 6079 argv[4] = "is" 6080 argv[5] = "a" 6081 argv[6] = "test." 6082 argv[7] = "<NULL>" 6083 Hit any key to exit ... 6084 6085 ## Application terminated, rc = 0x0 6086 6087Another example, which demonstrates how to register a CPM interrupt 6088handler with the U-Boot code, can be found in 'examples/timer.c'. 6089Here, a CPM timer is set up to generate an interrupt every second. 6090The interrupt service routine is trivial, just printing a '.' 6091character, but this is just a demo program. The application can be 6092controlled by the following keys: 6093 6094 ? - print current values og the CPM Timer registers 6095 b - enable interrupts and start timer 6096 e - stop timer and disable interrupts 6097 q - quit application 6098 6099 => loads 6100 ## Ready for S-Record download ... 6101 ~>examples/timer.srec 6102 1 2 3 4 5 6 7 8 9 10 11 ... 6103 [file transfer complete] 6104 [connected] 6105 ## Start Addr = 0x00040004 6106 6107 => go 40004 6108 ## Starting application at 0x00040004 ... 6109 TIMERS=0xfff00980 6110 Using timer 1 6111 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6112 6113Hit 'b': 6114 [q, b, e, ?] Set interval 1000000 us 6115 Enabling timer 6116Hit '?': 6117 [q, b, e, ?] ........ 6118 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6119Hit '?': 6120 [q, b, e, ?] . 6121 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6122Hit '?': 6123 [q, b, e, ?] . 6124 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6125Hit '?': 6126 [q, b, e, ?] . 6127 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6128Hit 'e': 6129 [q, b, e, ?] ...Stopping timer 6130Hit 'q': 6131 [q, b, e, ?] ## Application terminated, rc = 0x0 6132 6133 6134Minicom warning: 6135================ 6136 6137Over time, many people have reported problems when trying to use the 6138"minicom" terminal emulation program for serial download. I (wd) 6139consider minicom to be broken, and recommend not to use it. Under 6140Unix, I recommend to use C-Kermit for general purpose use (and 6141especially for kermit binary protocol download ("loadb" command), and 6142use "cu" for S-Record download ("loads" command). See 6143http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6144for help with kermit. 6145 6146 6147Nevertheless, if you absolutely want to use it try adding this 6148configuration to your "File transfer protocols" section: 6149 6150 Name Program Name U/D FullScr IO-Red. Multi 6151 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6152 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6153 6154 6155NetBSD Notes: 6156============= 6157 6158Starting at version 0.9.2, U-Boot supports NetBSD both as host 6159(build U-Boot) and target system (boots NetBSD/mpc8xx). 6160 6161Building requires a cross environment; it is known to work on 6162NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6163need gmake since the Makefiles are not compatible with BSD make). 6164Note that the cross-powerpc package does not install include files; 6165attempting to build U-Boot will fail because <machine/ansi.h> is 6166missing. This file has to be installed and patched manually: 6167 6168 # cd /usr/pkg/cross/powerpc-netbsd/include 6169 # mkdir powerpc 6170 # ln -s powerpc machine 6171 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6172 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6173 6174Native builds *don't* work due to incompatibilities between native 6175and U-Boot include files. 6176 6177Booting assumes that (the first part of) the image booted is a 6178stage-2 loader which in turn loads and then invokes the kernel 6179proper. Loader sources will eventually appear in the NetBSD source 6180tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6181meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6182 6183 6184Implementation Internals: 6185========================= 6186 6187The following is not intended to be a complete description of every 6188implementation detail. However, it should help to understand the 6189inner workings of U-Boot and make it easier to port it to custom 6190hardware. 6191 6192 6193Initial Stack, Global Data: 6194--------------------------- 6195 6196The implementation of U-Boot is complicated by the fact that U-Boot 6197starts running out of ROM (flash memory), usually without access to 6198system RAM (because the memory controller is not initialized yet). 6199This means that we don't have writable Data or BSS segments, and BSS 6200is not initialized as zero. To be able to get a C environment working 6201at all, we have to allocate at least a minimal stack. Implementation 6202options for this are defined and restricted by the CPU used: Some CPU 6203models provide on-chip memory (like the IMMR area on MPC8xx and 6204MPC826x processors), on others (parts of) the data cache can be 6205locked as (mis-) used as memory, etc. 6206 6207 Chris Hallinan posted a good summary of these issues to the 6208 U-Boot mailing list: 6209 6210 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6211 From: "Chris Hallinan" <clh@net1plus.com> 6212 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6213 ... 6214 6215 Correct me if I'm wrong, folks, but the way I understand it 6216 is this: Using DCACHE as initial RAM for Stack, etc, does not 6217 require any physical RAM backing up the cache. The cleverness 6218 is that the cache is being used as a temporary supply of 6219 necessary storage before the SDRAM controller is setup. It's 6220 beyond the scope of this list to explain the details, but you 6221 can see how this works by studying the cache architecture and 6222 operation in the architecture and processor-specific manuals. 6223 6224 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6225 is another option for the system designer to use as an 6226 initial stack/RAM area prior to SDRAM being available. Either 6227 option should work for you. Using CS 4 should be fine if your 6228 board designers haven't used it for something that would 6229 cause you grief during the initial boot! It is frequently not 6230 used. 6231 6232 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6233 with your processor/board/system design. The default value 6234 you will find in any recent u-boot distribution in 6235 walnut.h should work for you. I'd set it to a value larger 6236 than your SDRAM module. If you have a 64MB SDRAM module, set 6237 it above 400_0000. Just make sure your board has no resources 6238 that are supposed to respond to that address! That code in 6239 start.S has been around a while and should work as is when 6240 you get the config right. 6241 6242 -Chris Hallinan 6243 DS4.COM, Inc. 6244 6245It is essential to remember this, since it has some impact on the C 6246code for the initialization procedures: 6247 6248* Initialized global data (data segment) is read-only. Do not attempt 6249 to write it. 6250 6251* Do not use any uninitialized global data (or implicitly initialized 6252 as zero data - BSS segment) at all - this is undefined, initiali- 6253 zation is performed later (when relocating to RAM). 6254 6255* Stack space is very limited. Avoid big data buffers or things like 6256 that. 6257 6258Having only the stack as writable memory limits means we cannot use 6259normal global data to share information between the code. But it 6260turned out that the implementation of U-Boot can be greatly 6261simplified by making a global data structure (gd_t) available to all 6262functions. We could pass a pointer to this data as argument to _all_ 6263functions, but this would bloat the code. Instead we use a feature of 6264the GCC compiler (Global Register Variables) to share the data: we 6265place a pointer (gd) to the global data into a register which we 6266reserve for this purpose. 6267 6268When choosing a register for such a purpose we are restricted by the 6269relevant (E)ABI specifications for the current architecture, and by 6270GCC's implementation. 6271 6272For PowerPC, the following registers have specific use: 6273 R1: stack pointer 6274 R2: reserved for system use 6275 R3-R4: parameter passing and return values 6276 R5-R10: parameter passing 6277 R13: small data area pointer 6278 R30: GOT pointer 6279 R31: frame pointer 6280 6281 (U-Boot also uses R12 as internal GOT pointer. r12 6282 is a volatile register so r12 needs to be reset when 6283 going back and forth between asm and C) 6284 6285 ==> U-Boot will use R2 to hold a pointer to the global data 6286 6287 Note: on PPC, we could use a static initializer (since the 6288 address of the global data structure is known at compile time), 6289 but it turned out that reserving a register results in somewhat 6290 smaller code - although the code savings are not that big (on 6291 average for all boards 752 bytes for the whole U-Boot image, 6292 624 text + 127 data). 6293 6294On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6295 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6296 6297 ==> U-Boot will use P3 to hold a pointer to the global data 6298 6299On ARM, the following registers are used: 6300 6301 R0: function argument word/integer result 6302 R1-R3: function argument word 6303 R9: platform specific 6304 R10: stack limit (used only if stack checking is enabled) 6305 R11: argument (frame) pointer 6306 R12: temporary workspace 6307 R13: stack pointer 6308 R14: link register 6309 R15: program counter 6310 6311 ==> U-Boot will use R9 to hold a pointer to the global data 6312 6313 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6314 6315On Nios II, the ABI is documented here: 6316 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6317 6318 ==> U-Boot will use gp to hold a pointer to the global data 6319 6320 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6321 to access small data sections, so gp is free. 6322 6323On NDS32, the following registers are used: 6324 6325 R0-R1: argument/return 6326 R2-R5: argument 6327 R15: temporary register for assembler 6328 R16: trampoline register 6329 R28: frame pointer (FP) 6330 R29: global pointer (GP) 6331 R30: link register (LP) 6332 R31: stack pointer (SP) 6333 PC: program counter (PC) 6334 6335 ==> U-Boot will use R10 to hold a pointer to the global data 6336 6337NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6338or current versions of GCC may "optimize" the code too much. 6339 6340Memory Management: 6341------------------ 6342 6343U-Boot runs in system state and uses physical addresses, i.e. the 6344MMU is not used either for address mapping nor for memory protection. 6345 6346The available memory is mapped to fixed addresses using the memory 6347controller. In this process, a contiguous block is formed for each 6348memory type (Flash, SDRAM, SRAM), even when it consists of several 6349physical memory banks. 6350 6351U-Boot is installed in the first 128 kB of the first Flash bank (on 6352TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6353booting and sizing and initializing DRAM, the code relocates itself 6354to the upper end of DRAM. Immediately below the U-Boot code some 6355memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6356configuration setting]. Below that, a structure with global Board 6357Info data is placed, followed by the stack (growing downward). 6358 6359Additionally, some exception handler code is copied to the low 8 kB 6360of DRAM (0x00000000 ... 0x00001FFF). 6361 6362So a typical memory configuration with 16 MB of DRAM could look like 6363this: 6364 6365 0x0000 0000 Exception Vector code 6366 : 6367 0x0000 1FFF 6368 0x0000 2000 Free for Application Use 6369 : 6370 : 6371 6372 : 6373 : 6374 0x00FB FF20 Monitor Stack (Growing downward) 6375 0x00FB FFAC Board Info Data and permanent copy of global data 6376 0x00FC 0000 Malloc Arena 6377 : 6378 0x00FD FFFF 6379 0x00FE 0000 RAM Copy of Monitor Code 6380 ... eventually: LCD or video framebuffer 6381 ... eventually: pRAM (Protected RAM - unchanged by reset) 6382 0x00FF FFFF [End of RAM] 6383 6384 6385System Initialization: 6386---------------------- 6387 6388In the reset configuration, U-Boot starts at the reset entry point 6389(on most PowerPC systems at address 0x00000100). Because of the reset 6390configuration for CS0# this is a mirror of the on board Flash memory. 6391To be able to re-map memory U-Boot then jumps to its link address. 6392To be able to implement the initialization code in C, a (small!) 6393initial stack is set up in the internal Dual Ported RAM (in case CPUs 6394which provide such a feature like MPC8xx or MPC8260), or in a locked 6395part of the data cache. After that, U-Boot initializes the CPU core, 6396the caches and the SIU. 6397 6398Next, all (potentially) available memory banks are mapped using a 6399preliminary mapping. For example, we put them on 512 MB boundaries 6400(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6401on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6402programmed for SDRAM access. Using the temporary configuration, a 6403simple memory test is run that determines the size of the SDRAM 6404banks. 6405 6406When there is more than one SDRAM bank, and the banks are of 6407different size, the largest is mapped first. For equal size, the first 6408bank (CS2#) is mapped first. The first mapping is always for address 64090x00000000, with any additional banks following immediately to create 6410contiguous memory starting from 0. 6411 6412Then, the monitor installs itself at the upper end of the SDRAM area 6413and allocates memory for use by malloc() and for the global Board 6414Info data; also, the exception vector code is copied to the low RAM 6415pages, and the final stack is set up. 6416 6417Only after this relocation will you have a "normal" C environment; 6418until that you are restricted in several ways, mostly because you are 6419running from ROM, and because the code will have to be relocated to a 6420new address in RAM. 6421 6422 6423U-Boot Porting Guide: 6424---------------------- 6425 6426[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6427list, October 2002] 6428 6429 6430int main(int argc, char *argv[]) 6431{ 6432 sighandler_t no_more_time; 6433 6434 signal(SIGALRM, no_more_time); 6435 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6436 6437 if (available_money > available_manpower) { 6438 Pay consultant to port U-Boot; 6439 return 0; 6440 } 6441 6442 Download latest U-Boot source; 6443 6444 Subscribe to u-boot mailing list; 6445 6446 if (clueless) 6447 email("Hi, I am new to U-Boot, how do I get started?"); 6448 6449 while (learning) { 6450 Read the README file in the top level directory; 6451 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6452 Read applicable doc/*.README; 6453 Read the source, Luke; 6454 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6455 } 6456 6457 if (available_money > toLocalCurrency ($2500)) 6458 Buy a BDI3000; 6459 else 6460 Add a lot of aggravation and time; 6461 6462 if (a similar board exists) { /* hopefully... */ 6463 cp -a board/<similar> board/<myboard> 6464 cp include/configs/<similar>.h include/configs/<myboard>.h 6465 } else { 6466 Create your own board support subdirectory; 6467 Create your own board include/configs/<myboard>.h file; 6468 } 6469 Edit new board/<myboard> files 6470 Edit new include/configs/<myboard>.h 6471 6472 while (!accepted) { 6473 while (!running) { 6474 do { 6475 Add / modify source code; 6476 } until (compiles); 6477 Debug; 6478 if (clueless) 6479 email("Hi, I am having problems..."); 6480 } 6481 Send patch file to the U-Boot email list; 6482 if (reasonable critiques) 6483 Incorporate improvements from email list code review; 6484 else 6485 Defend code as written; 6486 } 6487 6488 return 0; 6489} 6490 6491void no_more_time (int sig) 6492{ 6493 hire_a_guru(); 6494} 6495 6496 6497Coding Standards: 6498----------------- 6499 6500All contributions to U-Boot should conform to the Linux kernel 6501coding style; see the file "Documentation/CodingStyle" and the script 6502"scripts/Lindent" in your Linux kernel source directory. 6503 6504Source files originating from a different project (for example the 6505MTD subsystem) are generally exempt from these guidelines and are not 6506reformatted to ease subsequent migration to newer versions of those 6507sources. 6508 6509Please note that U-Boot is implemented in C (and to some small parts in 6510Assembler); no C++ is used, so please do not use C++ style comments (//) 6511in your code. 6512 6513Please also stick to the following formatting rules: 6514- remove any trailing white space 6515- use TAB characters for indentation and vertical alignment, not spaces 6516- make sure NOT to use DOS '\r\n' line feeds 6517- do not add more than 2 consecutive empty lines to source files 6518- do not add trailing empty lines to source files 6519 6520Submissions which do not conform to the standards may be returned 6521with a request to reformat the changes. 6522 6523 6524Submitting Patches: 6525------------------- 6526 6527Since the number of patches for U-Boot is growing, we need to 6528establish some rules. Submissions which do not conform to these rules 6529may be rejected, even when they contain important and valuable stuff. 6530 6531Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6532 6533Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6534see http://lists.denx.de/mailman/listinfo/u-boot 6535 6536When you send a patch, please include the following information with 6537it: 6538 6539* For bug fixes: a description of the bug and how your patch fixes 6540 this bug. Please try to include a way of demonstrating that the 6541 patch actually fixes something. 6542 6543* For new features: a description of the feature and your 6544 implementation. 6545 6546* A CHANGELOG entry as plaintext (separate from the patch) 6547 6548* For major contributions, add a MAINTAINERS file with your 6549 information and associated file and directory references. 6550 6551* When you add support for a new board, don't forget to add a 6552 maintainer e-mail address to the boards.cfg file, too. 6553 6554* If your patch adds new configuration options, don't forget to 6555 document these in the README file. 6556 6557* The patch itself. If you are using git (which is *strongly* 6558 recommended) you can easily generate the patch using the 6559 "git format-patch". If you then use "git send-email" to send it to 6560 the U-Boot mailing list, you will avoid most of the common problems 6561 with some other mail clients. 6562 6563 If you cannot use git, use "diff -purN OLD NEW". If your version of 6564 diff does not support these options, then get the latest version of 6565 GNU diff. 6566 6567 The current directory when running this command shall be the parent 6568 directory of the U-Boot source tree (i. e. please make sure that 6569 your patch includes sufficient directory information for the 6570 affected files). 6571 6572 We prefer patches as plain text. MIME attachments are discouraged, 6573 and compressed attachments must not be used. 6574 6575* If one logical set of modifications affects or creates several 6576 files, all these changes shall be submitted in a SINGLE patch file. 6577 6578* Changesets that contain different, unrelated modifications shall be 6579 submitted as SEPARATE patches, one patch per changeset. 6580 6581 6582Notes: 6583 6584* Before sending the patch, run the MAKEALL script on your patched 6585 source tree and make sure that no errors or warnings are reported 6586 for any of the boards. 6587 6588* Keep your modifications to the necessary minimum: A patch 6589 containing several unrelated changes or arbitrary reformats will be 6590 returned with a request to re-formatting / split it. 6591 6592* If you modify existing code, make sure that your new code does not 6593 add to the memory footprint of the code ;-) Small is beautiful! 6594 When adding new features, these should compile conditionally only 6595 (using #ifdef), and the resulting code with the new feature 6596 disabled must not need more memory than the old code without your 6597 modification. 6598 6599* Remember that there is a size limit of 100 kB per message on the 6600 u-boot mailing list. Bigger patches will be moderated. If they are 6601 reasonable and not too big, they will be acknowledged. But patches 6602 bigger than the size limit should be avoided. 6603