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 candidate 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 /m68k Files generic to m68k architecture 141 /microblaze Files generic to microblaze architecture 142 /mips Files generic to MIPS architecture 143 /nds32 Files generic to NDS32 architecture 144 /nios2 Files generic to Altera NIOS2 architecture 145 /openrisc Files generic to OpenRISC architecture 146 /powerpc Files generic to PowerPC architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /x86 Files generic to x86 architecture 150/api Machine/arch independent API for external apps 151/board Board dependent files 152/cmd U-Boot commands functions 153/common Misc architecture independent functions 154/configs Board default configuration files 155/disk Code for disk drive partition handling 156/doc Documentation (don't expect too much) 157/drivers Commonly used device drivers 158/dts Contains Makefile for building internal U-Boot fdt. 159/examples Example code for standalone applications, etc. 160/fs Filesystem code (cramfs, ext2, jffs2, etc.) 161/include Header Files 162/lib Library routines generic to all architectures 163/Licenses Various license files 164/net Networking code 165/post Power On Self Test 166/scripts Various build scripts and Makefiles 167/test Various unit test files 168/tools Tools to build S-Record or U-Boot images, etc. 169 170Software Configuration: 171======================= 172 173Configuration is usually done using C preprocessor defines; the 174rationale behind that is to avoid dead code whenever possible. 175 176There are two classes of configuration variables: 177 178* Configuration _OPTIONS_: 179 These are selectable by the user and have names beginning with 180 "CONFIG_". 181 182* Configuration _SETTINGS_: 183 These depend on the hardware etc. and should not be meddled with if 184 you don't know what you're doing; they have names beginning with 185 "CONFIG_SYS_". 186 187Previously, all configuration was done by hand, which involved creating 188symbolic links and editing configuration files manually. More recently, 189U-Boot has added the Kbuild infrastructure used by the Linux kernel, 190allowing you to use the "make menuconfig" command to configure your 191build. 192 193 194Selection of Processor Architecture and Board Type: 195--------------------------------------------------- 196 197For all supported boards there are ready-to-use default 198configurations available; just type "make <board_name>_defconfig". 199 200Example: For a TQM823L module type: 201 202 cd u-boot 203 make TQM823L_defconfig 204 205Note: If you're looking for the default configuration file for a board 206you're sure used to be there but is now missing, check the file 207doc/README.scrapyard for a list of no longer supported boards. 208 209Sandbox Environment: 210-------------------- 211 212U-Boot can be built natively to run on a Linux host using the 'sandbox' 213board. This allows feature development which is not board- or architecture- 214specific to be undertaken on a native platform. The sandbox is also used to 215run some of U-Boot's tests. 216 217See board/sandbox/README.sandbox for more details. 218 219 220Board Initialisation Flow: 221-------------------------- 222 223This is the intended start-up flow for boards. This should apply for both 224SPL and U-Boot proper (i.e. they both follow the same rules). 225 226Note: "SPL" stands for "Secondary Program Loader," which is explained in 227more detail later in this file. 228 229At present, SPL mostly uses a separate code path, but the function names 230and roles of each function are the same. Some boards or architectures 231may not conform to this. At least most ARM boards which use 232CONFIG_SPL_FRAMEWORK conform to this. 233 234Execution typically starts with an architecture-specific (and possibly 235CPU-specific) start.S file, such as: 236 237 - arch/arm/cpu/armv7/start.S 238 - arch/powerpc/cpu/mpc83xx/start.S 239 - arch/mips/cpu/start.S 240 241and so on. From there, three functions are called; the purpose and 242limitations of each of these functions are described below. 243 244lowlevel_init(): 245 - purpose: essential init to permit execution to reach board_init_f() 246 - no global_data or BSS 247 - there is no stack (ARMv7 may have one but it will soon be removed) 248 - must not set up SDRAM or use console 249 - must only do the bare minimum to allow execution to continue to 250 board_init_f() 251 - this is almost never needed 252 - return normally from this function 253 254board_init_f(): 255 - purpose: set up the machine ready for running board_init_r(): 256 i.e. SDRAM and serial UART 257 - global_data is available 258 - stack is in SRAM 259 - BSS is not available, so you cannot use global/static variables, 260 only stack variables and global_data 261 262 Non-SPL-specific notes: 263 - dram_init() is called to set up DRAM. If already done in SPL this 264 can do nothing 265 266 SPL-specific notes: 267 - you can override the entire board_init_f() function with your own 268 version as needed. 269 - preloader_console_init() can be called here in extremis 270 - should set up SDRAM, and anything needed to make the UART work 271 - these is no need to clear BSS, it will be done by crt0.S 272 - must return normally from this function (don't call board_init_r() 273 directly) 274 275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 276this point the stack and global_data are relocated to below 277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 278memory. 279 280board_init_r(): 281 - purpose: main execution, common code 282 - global_data is available 283 - SDRAM is available 284 - BSS is available, all static/global variables can be used 285 - execution eventually continues to main_loop() 286 287 Non-SPL-specific notes: 288 - U-Boot is relocated to the top of memory and is now running from 289 there. 290 291 SPL-specific notes: 292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 293 CONFIG_SPL_STACK_R_ADDR points into SDRAM 294 - preloader_console_init() can be called here - typically this is 295 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a 296 spl_board_init() function containing this call 297 - loads U-Boot or (in falcon mode) Linux 298 299 300 301Configuration Options: 302---------------------- 303 304Configuration depends on the combination of board and CPU type; all 305such information is kept in a configuration file 306"include/configs/<board_name>.h". 307 308Example: For a TQM823L module, all configuration settings are in 309"include/configs/TQM823L.h". 310 311 312Many of the options are named exactly as the corresponding Linux 313kernel configuration options. The intention is to make it easier to 314build a config tool - later. 315 316 317The following options need to be configured: 318 319- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 320 321- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 322 323- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 324 Define exactly one, e.g. CONFIG_ATSTK1002 325 326- Marvell Family Member 327 CONFIG_SYS_MVFS - define it if you want to enable 328 multiple fs option at one time 329 for marvell soc family 330 331- 8xx CPU Options: (if using an MPC8xx CPU) 332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 333 get_gclk_freq() cannot work 334 e.g. if there is no 32KHz 335 reference PIT/RTC clock 336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 337 or XTAL/EXTAL) 338 339- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 340 CONFIG_SYS_8xx_CPUCLK_MIN 341 CONFIG_SYS_8xx_CPUCLK_MAX 342 CONFIG_8xx_CPUCLK_DEFAULT 343 See doc/README.MPC866 344 345 CONFIG_SYS_MEASURE_CPUCLK 346 347 Define this to measure the actual CPU clock instead 348 of relying on the correctness of the configured 349 values. Mostly useful for board bringup to make sure 350 the PLL is locked at the intended frequency. Note 351 that this requires a (stable) reference clock (32 kHz 352 RTC clock or CONFIG_SYS_8XX_XIN) 353 354 CONFIG_SYS_DELAYED_ICACHE 355 356 Define this option if you want to enable the 357 ICache only when Code runs from RAM. 358 359- 85xx CPU Options: 360 CONFIG_SYS_PPC64 361 362 Specifies that the core is a 64-bit PowerPC implementation (implements 363 the "64" category of the Power ISA). This is necessary for ePAPR 364 compliance, among other possible reasons. 365 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377 CONFIG_SYS_FSL_ERRATUM_A004510 378 379 Enables a workaround for erratum A004510. If set, 380 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 381 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 382 383 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 385 386 Defines one or two SoC revisions (low 8 bits of SVR) 387 for which the A004510 workaround should be applied. 388 389 The rest of SVR is either not relevant to the decision 390 of whether the erratum is present (e.g. p2040 versus 391 p2041) or is implied by the build target, which controls 392 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 393 394 See Freescale App Note 4493 for more information about 395 this erratum. 396 397 CONFIG_A003399_NOR_WORKAROUND 398 Enables a workaround for IFC erratum A003399. It is only 399 required during NOR boot. 400 401 CONFIG_A008044_WORKAROUND 402 Enables a workaround for T1040/T1042 erratum A008044. It is only 403 required during NAND boot and valid for Rev 1.0 SoC revision 404 405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 406 407 This is the value to write into CCSR offset 0x18600 408 according to the A004510 workaround. 409 410 CONFIG_SYS_FSL_DSP_DDR_ADDR 411 This value denotes start offset of DDR memory which is 412 connected exclusively to the DSP cores. 413 414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 415 This value denotes start offset of M2 memory 416 which is directly connected to the DSP core. 417 418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 419 This value denotes start offset of M3 memory which is directly 420 connected to the DSP core. 421 422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 423 This value denotes start offset of DSP CCSR space. 424 425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 426 Single Source Clock is clocking mode present in some of FSL SoC's. 427 In this mode, a single differential clock is used to supply 428 clocks to the sysclock, ddrclock and usbclock. 429 430 CONFIG_SYS_CPC_REINIT_F 431 This CONFIG is defined when the CPC is configured as SRAM at the 432 time of U-Boot entry and is required to be re-initialized. 433 434 CONFIG_DEEP_SLEEP 435 Indicates this SoC supports deep sleep feature. If deep sleep is 436 supported, core will start to execute uboot when wakes up. 437 438- Generic CPU options: 439 CONFIG_SYS_GENERIC_GLOBAL_DATA 440 Defines global data is initialized in generic board board_init_f(). 441 If this macro is defined, global data is created and cleared in 442 generic board board_init_f(). Without this macro, architecture/board 443 should initialize global data before calling board_init_f(). 444 445 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 446 447 Defines the endianess of the CPU. Implementation of those 448 values is arch specific. 449 450 CONFIG_SYS_FSL_DDR 451 Freescale DDR driver in use. This type of DDR controller is 452 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 453 SoCs. 454 455 CONFIG_SYS_FSL_DDR_ADDR 456 Freescale DDR memory-mapped register base. 457 458 CONFIG_SYS_FSL_DDR_EMU 459 Specify emulator support for DDR. Some DDR features such as 460 deskew training are not available. 461 462 CONFIG_SYS_FSL_DDRC_GEN1 463 Freescale DDR1 controller. 464 465 CONFIG_SYS_FSL_DDRC_GEN2 466 Freescale DDR2 controller. 467 468 CONFIG_SYS_FSL_DDRC_GEN3 469 Freescale DDR3 controller. 470 471 CONFIG_SYS_FSL_DDRC_GEN4 472 Freescale DDR4 controller. 473 474 CONFIG_SYS_FSL_DDRC_ARM_GEN3 475 Freescale DDR3 controller for ARM-based SoCs. 476 477 CONFIG_SYS_FSL_DDR1 478 Board config to use DDR1. It can be enabled for SoCs with 479 Freescale DDR1 or DDR2 controllers, depending on the board 480 implemetation. 481 482 CONFIG_SYS_FSL_DDR2 483 Board config to use DDR2. It can be enabled for SoCs with 484 Freescale DDR2 or DDR3 controllers, depending on the board 485 implementation. 486 487 CONFIG_SYS_FSL_DDR3 488 Board config to use DDR3. It can be enabled for SoCs with 489 Freescale DDR3 or DDR3L controllers. 490 491 CONFIG_SYS_FSL_DDR3L 492 Board config to use DDR3L. It can be enabled for SoCs with 493 DDR3L controllers. 494 495 CONFIG_SYS_FSL_DDR4 496 Board config to use DDR4. It can be enabled for SoCs with 497 DDR4 controllers. 498 499 CONFIG_SYS_FSL_IFC_BE 500 Defines the IFC controller register space as Big Endian 501 502 CONFIG_SYS_FSL_IFC_LE 503 Defines the IFC controller register space as Little Endian 504 505 CONFIG_SYS_FSL_IFC_CLK_DIV 506 Defines divider of platform clock(clock input to IFC controller). 507 508 CONFIG_SYS_FSL_LBC_CLK_DIV 509 Defines divider of platform clock(clock input to eLBC controller). 510 511 CONFIG_SYS_FSL_PBL_PBI 512 It enables addition of RCW (Power on reset configuration) in built image. 513 Please refer doc/README.pblimage for more details 514 515 CONFIG_SYS_FSL_PBL_RCW 516 It adds PBI(pre-boot instructions) commands in u-boot build image. 517 PBI commands can be used to configure SoC before it starts the execution. 518 Please refer doc/README.pblimage for more details 519 520 CONFIG_SPL_FSL_PBL 521 It adds a target to create boot binary having SPL binary in PBI format 522 concatenated with u-boot binary. 523 524 CONFIG_SYS_FSL_DDR_BE 525 Defines the DDR controller register space as Big Endian 526 527 CONFIG_SYS_FSL_DDR_LE 528 Defines the DDR controller register space as Little Endian 529 530 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 531 Physical address from the view of DDR controllers. It is the 532 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 533 it could be different for ARM SoCs. 534 535 CONFIG_SYS_FSL_DDR_INTLV_256B 536 DDR controller interleaving on 256-byte. This is a special 537 interleaving mode, handled by Dickens for Freescale layerscape 538 SoCs with ARM core. 539 540 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 541 Number of controllers used as main memory. 542 543 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 544 Number of controllers used for other than main memory. 545 546 CONFIG_SYS_FSL_HAS_DP_DDR 547 Defines the SoC has DP-DDR used for DPAA. 548 549 CONFIG_SYS_FSL_SEC_BE 550 Defines the SEC controller register space as Big Endian 551 552 CONFIG_SYS_FSL_SEC_LE 553 Defines the SEC controller register space as Little Endian 554 555- MIPS CPU options: 556 CONFIG_SYS_INIT_SP_OFFSET 557 558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 559 pointer. This is needed for the temporary stack before 560 relocation. 561 562 CONFIG_SYS_MIPS_CACHE_MODE 563 564 Cache operation mode for the MIPS CPU. 565 See also arch/mips/include/asm/mipsregs.h. 566 Possible values are: 567 CONF_CM_CACHABLE_NO_WA 568 CONF_CM_CACHABLE_WA 569 CONF_CM_UNCACHED 570 CONF_CM_CACHABLE_NONCOHERENT 571 CONF_CM_CACHABLE_CE 572 CONF_CM_CACHABLE_COW 573 CONF_CM_CACHABLE_CUW 574 CONF_CM_CACHABLE_ACCELERATED 575 576 CONFIG_SYS_XWAY_EBU_BOOTCFG 577 578 Special option for Lantiq XWAY SoCs for booting from NOR flash. 579 See also arch/mips/cpu/mips32/start.S. 580 581 CONFIG_XWAY_SWAP_BYTES 582 583 Enable compilation of tools/xway-swap-bytes needed for Lantiq 584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 585 be swapped if a flash programmer is used. 586 587- ARM options: 588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 589 590 Select high exception vectors of the ARM core, e.g., do not 591 clear the V bit of the c1 register of CP15. 592 593 COUNTER_FREQUENCY 594 Generic timer clock source frequency. 595 596 COUNTER_FREQUENCY_REAL 597 Generic timer clock source frequency if the real clock is 598 different from COUNTER_FREQUENCY, and can only be determined 599 at run time. 600 601- Tegra SoC options: 602 CONFIG_TEGRA_SUPPORT_NON_SECURE 603 604 Support executing U-Boot in non-secure (NS) mode. Certain 605 impossible actions will be skipped if the CPU is in NS mode, 606 such as ARM architectural timer initialization. 607 608- Linux Kernel Interface: 609 CONFIG_CLOCKS_IN_MHZ 610 611 U-Boot stores all clock information in Hz 612 internally. For binary compatibility with older Linux 613 kernels (which expect the clocks passed in the 614 bd_info data to be in MHz) the environment variable 615 "clocks_in_mhz" can be defined so that U-Boot 616 converts clock data to MHZ before passing it to the 617 Linux kernel. 618 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 619 "clocks_in_mhz=1" is automatically included in the 620 default environment. 621 622 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 623 624 When transferring memsize parameter to Linux, some versions 625 expect it to be in bytes, others in MB. 626 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 627 628 CONFIG_OF_LIBFDT 629 630 New kernel versions are expecting firmware settings to be 631 passed using flattened device trees (based on open firmware 632 concepts). 633 634 CONFIG_OF_LIBFDT 635 * New libfdt-based support 636 * Adds the "fdt" command 637 * The bootm command automatically updates the fdt 638 639 OF_CPU - The proper name of the cpus node (only required for 640 MPC512X and MPC5xxx based boards). 641 OF_SOC - The proper name of the soc node (only required for 642 MPC512X and MPC5xxx based boards). 643 OF_TBCLK - The timebase frequency. 644 OF_STDOUT_PATH - The path to the console device 645 646 boards with QUICC Engines require OF_QE to set UCC MAC 647 addresses 648 649 CONFIG_OF_BOARD_SETUP 650 651 Board code has addition modification that it wants to make 652 to the flat device tree before handing it off to the kernel 653 654 CONFIG_OF_SYSTEM_SETUP 655 656 Other code has addition modification that it wants to make 657 to the flat device tree before handing it off to the kernel. 658 This causes ft_system_setup() to be called before booting 659 the kernel. 660 661 CONFIG_OF_IDE_FIXUP 662 663 U-Boot can detect if an IDE device is present or not. 664 If not, and this new config option is activated, U-Boot 665 removes the ATA node from the DTS before booting Linux, 666 so the Linux IDE driver does not probe the device and 667 crash. This is needed for buggy hardware (uc101) where 668 no pull down resistor is connected to the signal IDE5V_DD7. 669 670 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 671 672 This setting is mandatory for all boards that have only one 673 machine type and must be used to specify the machine type 674 number as it appears in the ARM machine registry 675 (see http://www.arm.linux.org.uk/developer/machines/). 676 Only boards that have multiple machine types supported 677 in a single configuration file and the machine type is 678 runtime discoverable, do not have to use this setting. 679 680- vxWorks boot parameters: 681 682 bootvx constructs a valid bootline using the following 683 environments variables: bootdev, bootfile, ipaddr, netmask, 684 serverip, gatewayip, hostname, othbootargs. 685 It loads the vxWorks image pointed bootfile. 686 687 Note: If a "bootargs" environment is defined, it will overwride 688 the defaults discussed just above. 689 690- Cache Configuration: 691 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 692 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 693 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 694 695- Cache Configuration for ARM: 696 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 697 controller 698 CONFIG_SYS_PL310_BASE - Physical base address of PL310 699 controller register space 700 701- Serial Ports: 702 CONFIG_PL010_SERIAL 703 704 Define this if you want support for Amba PrimeCell PL010 UARTs. 705 706 CONFIG_PL011_SERIAL 707 708 Define this if you want support for Amba PrimeCell PL011 UARTs. 709 710 CONFIG_PL011_CLOCK 711 712 If you have Amba PrimeCell PL011 UARTs, set this variable to 713 the clock speed of the UARTs. 714 715 CONFIG_PL01x_PORTS 716 717 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 718 define this to a list of base addresses for each (supported) 719 port. See e.g. include/configs/versatile.h 720 721 CONFIG_SERIAL_HW_FLOW_CONTROL 722 723 Define this variable to enable hw flow control in serial driver. 724 Current user of this option is drivers/serial/nsl16550.c driver 725 726- Console Interface: 727 Depending on board, define exactly one serial port 728 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 729 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 730 console by defining CONFIG_8xx_CONS_NONE 731 732 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 733 port routines must be defined elsewhere 734 (i.e. serial_init(), serial_getc(), ...) 735 736- Console Baudrate: 737 CONFIG_BAUDRATE - in bps 738 Select one of the baudrates listed in 739 CONFIG_SYS_BAUDRATE_TABLE, see below. 740 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 741 742- Console Rx buffer length 743 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 744 the maximum receive buffer length for the SMC. 745 This option is actual only for 82xx and 8xx possible. 746 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 747 must be defined, to setup the maximum idle timeout for 748 the SMC. 749 750- Autoboot Command: 751 CONFIG_BOOTCOMMAND 752 Only needed when CONFIG_BOOTDELAY is enabled; 753 define a command string that is automatically executed 754 when no character is read on the console interface 755 within "Boot Delay" after reset. 756 757 CONFIG_BOOTARGS 758 This can be used to pass arguments to the bootm 759 command. The value of CONFIG_BOOTARGS goes into the 760 environment value "bootargs". 761 762 CONFIG_RAMBOOT and CONFIG_NFSBOOT 763 The value of these goes into the environment as 764 "ramboot" and "nfsboot" respectively, and can be used 765 as a convenience, when switching between booting from 766 RAM and NFS. 767 768- Bootcount: 769 CONFIG_BOOTCOUNT_LIMIT 770 Implements a mechanism for detecting a repeating reboot 771 cycle, see: 772 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 773 774 CONFIG_BOOTCOUNT_ENV 775 If no softreset save registers are found on the hardware 776 "bootcount" is stored in the environment. To prevent a 777 saveenv on all reboots, the environment variable 778 "upgrade_available" is used. If "upgrade_available" is 779 0, "bootcount" is always 0, if "upgrade_available" is 780 1 "bootcount" is incremented in the environment. 781 So the Userspace Applikation must set the "upgrade_available" 782 and "bootcount" variable to 0, if a boot was successfully. 783 784- Pre-Boot Commands: 785 CONFIG_PREBOOT 786 787 When this option is #defined, the existence of the 788 environment variable "preboot" will be checked 789 immediately before starting the CONFIG_BOOTDELAY 790 countdown and/or running the auto-boot command resp. 791 entering interactive mode. 792 793 This feature is especially useful when "preboot" is 794 automatically generated or modified. For an example 795 see the LWMON board specific code: here "preboot" is 796 modified when the user holds down a certain 797 combination of keys on the (special) keyboard when 798 booting the systems 799 800- Serial Download Echo Mode: 801 CONFIG_LOADS_ECHO 802 If defined to 1, all characters received during a 803 serial download (using the "loads" command) are 804 echoed back. This might be needed by some terminal 805 emulations (like "cu"), but may as well just take 806 time on others. This setting #define's the initial 807 value of the "loads_echo" environment variable. 808 809- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 810 CONFIG_KGDB_BAUDRATE 811 Select one of the baudrates listed in 812 CONFIG_SYS_BAUDRATE_TABLE, see below. 813 814- Monitor Functions: 815 Monitor commands can be included or excluded 816 from the build by using the #include files 817 <config_cmd_all.h> and #undef'ing unwanted 818 commands, or adding #define's for wanted commands. 819 820 The default command configuration includes all commands 821 except those marked below with a "*". 822 823 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 824 CONFIG_CMD_ASKENV * ask for env variable 825 CONFIG_CMD_BDI bdinfo 826 CONFIG_CMD_BOOTD bootd 827 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 828 CONFIG_CMD_CACHE * icache, dcache 829 CONFIG_CMD_CONSOLE coninfo 830 CONFIG_CMD_CRC32 * crc32 831 CONFIG_CMD_DHCP * DHCP support 832 CONFIG_CMD_DIAG * Diagnostics 833 CONFIG_CMD_ECHO echo arguments 834 CONFIG_CMD_EDITENV edit env variable 835 CONFIG_CMD_ELF * bootelf, bootvx 836 CONFIG_CMD_ENV_EXISTS * check existence of env variable 837 CONFIG_CMD_EXPORTENV * export the environment 838 CONFIG_CMD_EXT2 * ext2 command support 839 CONFIG_CMD_EXT4 * ext4 command support 840 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 841 that work for multiple fs types 842 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 843 CONFIG_CMD_SAVEENV saveenv 844 CONFIG_CMD_FAT * FAT command support 845 CONFIG_CMD_FLASH flinfo, erase, protect 846 CONFIG_CMD_FPGA FPGA device initialization support 847 CONFIG_CMD_FUSE * Device fuse support 848 CONFIG_CMD_GETTIME * Get time since boot 849 CONFIG_CMD_GO * the 'go' command (exec code) 850 CONFIG_CMD_GREPENV * search environment 851 CONFIG_CMD_HASH * calculate hash / digest 852 CONFIG_CMD_I2C * I2C serial bus support 853 CONFIG_CMD_IDE * IDE harddisk support 854 CONFIG_CMD_IMI iminfo 855 CONFIG_CMD_IMLS List all images found in NOR flash 856 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 857 CONFIG_CMD_IMMAP * IMMR dump support 858 CONFIG_CMD_IOTRACE * I/O tracing for debugging 859 CONFIG_CMD_IMPORTENV * import an environment 860 CONFIG_CMD_INI * import data from an ini file into the env 861 CONFIG_CMD_IRQ * irqinfo 862 CONFIG_CMD_ITEST Integer/string test of 2 values 863 CONFIG_CMD_JFFS2 * JFFS2 Support 864 CONFIG_CMD_KGDB * kgdb 865 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 866 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 867 (169.254.*.*) 868 CONFIG_CMD_LOADB loadb 869 CONFIG_CMD_LOADS loads 870 CONFIG_CMD_MD5SUM * print md5 message digest 871 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 872 CONFIG_CMD_MEMINFO * Display detailed memory information 873 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 874 loop, loopw 875 CONFIG_CMD_MEMTEST * mtest 876 CONFIG_CMD_MISC Misc functions like sleep etc 877 CONFIG_CMD_MMC * MMC memory mapped support 878 CONFIG_CMD_MII * MII utility commands 879 CONFIG_CMD_MTDPARTS * MTD partition support 880 CONFIG_CMD_NAND * NAND support 881 CONFIG_CMD_NET bootp, tftpboot, rarpboot 882 CONFIG_CMD_NFS NFS support 883 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 884 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 885 CONFIG_CMD_PCI * pciinfo 886 CONFIG_CMD_PCMCIA * PCMCIA support 887 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 888 host 889 CONFIG_CMD_PORTIO * Port I/O 890 CONFIG_CMD_READ * Read raw data from partition 891 CONFIG_CMD_REGINFO * Register dump 892 CONFIG_CMD_RUN run command in env variable 893 CONFIG_CMD_SANDBOX * sb command to access sandbox features 894 CONFIG_CMD_SAVES * save S record dump 895 CONFIG_SCSI * SCSI Support 896 CONFIG_CMD_SDRAM * print SDRAM configuration information 897 (requires CONFIG_CMD_I2C) 898 CONFIG_CMD_SETGETDCR Support for DCR Register access 899 (4xx only) 900 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 901 CONFIG_CMD_SHA1SUM * print sha1 memory digest 902 (requires CONFIG_CMD_MEMORY) 903 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 904 CONFIG_CMD_SOURCE "source" command Support 905 CONFIG_CMD_SPI * SPI serial bus support 906 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 907 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 908 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 909 CONFIG_CMD_TIMER * access to the system tick timer 910 CONFIG_CMD_USB * USB support 911 CONFIG_CMD_CDP * Cisco Discover Protocol support 912 CONFIG_CMD_MFSL * Microblaze FSL support 913 CONFIG_CMD_XIMG Load part of Multi Image 914 CONFIG_CMD_UUID * Generate random UUID or GUID string 915 916 EXAMPLE: If you want all functions except of network 917 support you can write: 918 919 #include "config_cmd_all.h" 920 #undef CONFIG_CMD_NET 921 922 Other Commands: 923 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 924 925 Note: Don't enable the "icache" and "dcache" commands 926 (configuration option CONFIG_CMD_CACHE) unless you know 927 what you (and your U-Boot users) are doing. Data 928 cache cannot be enabled on systems like the 8xx or 929 8260 (where accesses to the IMMR region must be 930 uncached), and it cannot be disabled on all other 931 systems where we (mis-) use the data cache to hold an 932 initial stack and some data. 933 934 935 XXX - this list needs to get updated! 936 937- Removal of commands 938 If no commands are needed to boot, you can disable 939 CONFIG_CMDLINE to remove them. In this case, the command line 940 will not be available, and when U-Boot wants to execute the 941 boot command (on start-up) it will call board_run_command() 942 instead. This can reduce image size significantly for very 943 simple boot procedures. 944 945- Regular expression support: 946 CONFIG_REGEX 947 If this variable is defined, U-Boot is linked against 948 the SLRE (Super Light Regular Expression) library, 949 which adds regex support to some commands, as for 950 example "env grep" and "setexpr". 951 952- Device tree: 953 CONFIG_OF_CONTROL 954 If this variable is defined, U-Boot will use a device tree 955 to configure its devices, instead of relying on statically 956 compiled #defines in the board file. This option is 957 experimental and only available on a few boards. The device 958 tree is available in the global data as gd->fdt_blob. 959 960 U-Boot needs to get its device tree from somewhere. This can 961 be done using one of the three options below: 962 963 CONFIG_OF_EMBED 964 If this variable is defined, U-Boot will embed a device tree 965 binary in its image. This device tree file should be in the 966 board directory and called <soc>-<board>.dts. The binary file 967 is then picked up in board_init_f() and made available through 968 the global data structure as gd->blob. 969 970 CONFIG_OF_SEPARATE 971 If this variable is defined, U-Boot will build a device tree 972 binary. It will be called u-boot.dtb. Architecture-specific 973 code will locate it at run-time. Generally this works by: 974 975 cat u-boot.bin u-boot.dtb >image.bin 976 977 and in fact, U-Boot does this for you, creating a file called 978 u-boot-dtb.bin which is useful in the common case. You can 979 still use the individual files if you need something more 980 exotic. 981 982 CONFIG_OF_BOARD 983 If this variable is defined, U-Boot will use the device tree 984 provided by the board at runtime instead of embedding one with 985 the image. Only boards defining board_fdt_blob_setup() support 986 this option (see include/fdtdec.h file). 987 988- Watchdog: 989 CONFIG_WATCHDOG 990 If this variable is defined, it enables watchdog 991 support for the SoC. There must be support in the SoC 992 specific code for a watchdog. For the 8xx and 8260 993 CPUs, the SIU Watchdog feature is enabled in the SYPCR 994 register. When supported for a specific SoC is 995 available, then no further board specific code should 996 be needed to use it. 997 998 CONFIG_HW_WATCHDOG 999 When using a watchdog circuitry external to the used 1000 SoC, then define this variable and provide board 1001 specific code for the "hw_watchdog_reset" function. 1002 1003 CONFIG_AT91_HW_WDT_TIMEOUT 1004 specify the timeout in seconds. default 2 seconds. 1005 1006- U-Boot Version: 1007 CONFIG_VERSION_VARIABLE 1008 If this variable is defined, an environment variable 1009 named "ver" is created by U-Boot showing the U-Boot 1010 version as printed by the "version" command. 1011 Any change to this variable will be reverted at the 1012 next reset. 1013 1014- Real-Time Clock: 1015 1016 When CONFIG_CMD_DATE is selected, the type of the RTC 1017 has to be selected, too. Define exactly one of the 1018 following options: 1019 1020 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1021 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1022 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1023 CONFIG_RTC_MC146818 - use MC146818 RTC 1024 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1025 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1026 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1027 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1028 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1029 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1030 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1031 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1032 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1033 RV3029 RTC. 1034 1035 Note that if the RTC uses I2C, then the I2C interface 1036 must also be configured. See I2C Support, below. 1037 1038- GPIO Support: 1039 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1040 1041 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1042 chip-ngpio pairs that tell the PCA953X driver the number of 1043 pins supported by a particular chip. 1044 1045 Note that if the GPIO device uses I2C, then the I2C interface 1046 must also be configured. See I2C Support, below. 1047 1048- I/O tracing: 1049 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1050 accesses and can checksum them or write a list of them out 1051 to memory. See the 'iotrace' command for details. This is 1052 useful for testing device drivers since it can confirm that 1053 the driver behaves the same way before and after a code 1054 change. Currently this is supported on sandbox and arm. To 1055 add support for your architecture, add '#include <iotrace.h>' 1056 to the bottom of arch/<arch>/include/asm/io.h and test. 1057 1058 Example output from the 'iotrace stats' command is below. 1059 Note that if the trace buffer is exhausted, the checksum will 1060 still continue to operate. 1061 1062 iotrace is enabled 1063 Start: 10000000 (buffer start address) 1064 Size: 00010000 (buffer size) 1065 Offset: 00000120 (current buffer offset) 1066 Output: 10000120 (start + offset) 1067 Count: 00000018 (number of trace records) 1068 CRC32: 9526fb66 (CRC32 of all trace records) 1069 1070- Timestamp Support: 1071 1072 When CONFIG_TIMESTAMP is selected, the timestamp 1073 (date and time) of an image is printed by image 1074 commands like bootm or iminfo. This option is 1075 automatically enabled when you select CONFIG_CMD_DATE . 1076 1077- Partition Labels (disklabels) Supported: 1078 Zero or more of the following: 1079 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1080 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1081 Intel architecture, USB sticks, etc. 1082 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1083 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1084 bootloader. Note 2TB partition limit; see 1085 disk/part_efi.c 1086 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1087 1088 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1089 CONFIG_SCSI) you must configure support for at 1090 least one non-MTD partition type as well. 1091 1092- IDE Reset method: 1093 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1094 board configurations files but used nowhere! 1095 1096 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1097 be performed by calling the function 1098 ide_set_reset(int reset) 1099 which has to be defined in a board specific file 1100 1101- ATAPI Support: 1102 CONFIG_ATAPI 1103 1104 Set this to enable ATAPI support. 1105 1106- LBA48 Support 1107 CONFIG_LBA48 1108 1109 Set this to enable support for disks larger than 137GB 1110 Also look at CONFIG_SYS_64BIT_LBA. 1111 Whithout these , LBA48 support uses 32bit variables and will 'only' 1112 support disks up to 2.1TB. 1113 1114 CONFIG_SYS_64BIT_LBA: 1115 When enabled, makes the IDE subsystem use 64bit sector addresses. 1116 Default is 32bit. 1117 1118- SCSI Support: 1119 At the moment only there is only support for the 1120 SYM53C8XX SCSI controller; define 1121 CONFIG_SCSI_SYM53C8XX to enable it. 1122 1123 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1124 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1125 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1126 maximum numbers of LUNs, SCSI ID's and target 1127 devices. 1128 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1129 1130 The environment variable 'scsidevs' is set to the number of 1131 SCSI devices found during the last scan. 1132 1133- NETWORK Support (PCI): 1134 CONFIG_E1000 1135 Support for Intel 8254x/8257x gigabit chips. 1136 1137 CONFIG_E1000_SPI 1138 Utility code for direct access to the SPI bus on Intel 8257x. 1139 This does not do anything useful unless you set at least one 1140 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1141 1142 CONFIG_E1000_SPI_GENERIC 1143 Allow generic access to the SPI bus on the Intel 8257x, for 1144 example with the "sspi" command. 1145 1146 CONFIG_CMD_E1000 1147 Management command for E1000 devices. When used on devices 1148 with SPI support you can reprogram the EEPROM from U-Boot. 1149 1150 CONFIG_EEPRO100 1151 Support for Intel 82557/82559/82559ER chips. 1152 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1153 write routine for first time initialisation. 1154 1155 CONFIG_TULIP 1156 Support for Digital 2114x chips. 1157 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1158 modem chip initialisation (KS8761/QS6611). 1159 1160 CONFIG_NATSEMI 1161 Support for National dp83815 chips. 1162 1163 CONFIG_NS8382X 1164 Support for National dp8382[01] gigabit chips. 1165 1166- NETWORK Support (other): 1167 1168 CONFIG_DRIVER_AT91EMAC 1169 Support for AT91RM9200 EMAC. 1170 1171 CONFIG_RMII 1172 Define this to use reduced MII inteface 1173 1174 CONFIG_DRIVER_AT91EMAC_QUIET 1175 If this defined, the driver is quiet. 1176 The driver doen't show link status messages. 1177 1178 CONFIG_CALXEDA_XGMAC 1179 Support for the Calxeda XGMAC device 1180 1181 CONFIG_LAN91C96 1182 Support for SMSC's LAN91C96 chips. 1183 1184 CONFIG_LAN91C96_USE_32_BIT 1185 Define this to enable 32 bit addressing 1186 1187 CONFIG_SMC91111 1188 Support for SMSC's LAN91C111 chip 1189 1190 CONFIG_SMC91111_BASE 1191 Define this to hold the physical address 1192 of the device (I/O space) 1193 1194 CONFIG_SMC_USE_32_BIT 1195 Define this if data bus is 32 bits 1196 1197 CONFIG_SMC_USE_IOFUNCS 1198 Define this to use i/o functions instead of macros 1199 (some hardware wont work with macros) 1200 1201 CONFIG_DRIVER_TI_EMAC 1202 Support for davinci emac 1203 1204 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1205 Define this if you have more then 3 PHYs. 1206 1207 CONFIG_FTGMAC100 1208 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1209 1210 CONFIG_FTGMAC100_EGIGA 1211 Define this to use GE link update with gigabit PHY. 1212 Define this if FTGMAC100 is connected to gigabit PHY. 1213 If your system has 10/100 PHY only, it might not occur 1214 wrong behavior. Because PHY usually return timeout or 1215 useless data when polling gigabit status and gigabit 1216 control registers. This behavior won't affect the 1217 correctnessof 10/100 link speed update. 1218 1219 CONFIG_SMC911X 1220 Support for SMSC's LAN911x and LAN921x chips 1221 1222 CONFIG_SMC911X_BASE 1223 Define this to hold the physical address 1224 of the device (I/O space) 1225 1226 CONFIG_SMC911X_32_BIT 1227 Define this if data bus is 32 bits 1228 1229 CONFIG_SMC911X_16_BIT 1230 Define this if data bus is 16 bits. If your processor 1231 automatically converts one 32 bit word to two 16 bit 1232 words you may also try CONFIG_SMC911X_32_BIT. 1233 1234 CONFIG_SH_ETHER 1235 Support for Renesas on-chip Ethernet controller 1236 1237 CONFIG_SH_ETHER_USE_PORT 1238 Define the number of ports to be used 1239 1240 CONFIG_SH_ETHER_PHY_ADDR 1241 Define the ETH PHY's address 1242 1243 CONFIG_SH_ETHER_CACHE_WRITEBACK 1244 If this option is set, the driver enables cache flush. 1245 1246- PWM Support: 1247 CONFIG_PWM_IMX 1248 Support for PWM module on the imx6. 1249 1250- TPM Support: 1251 CONFIG_TPM 1252 Support TPM devices. 1253 1254 CONFIG_TPM_TIS_INFINEON 1255 Support for Infineon i2c bus TPM devices. Only one device 1256 per system is supported at this time. 1257 1258 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1259 Define the burst count bytes upper limit 1260 1261 CONFIG_TPM_ST33ZP24 1262 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1263 1264 CONFIG_TPM_ST33ZP24_I2C 1265 Support for STMicroelectronics ST33ZP24 I2C devices. 1266 Requires TPM_ST33ZP24 and I2C. 1267 1268 CONFIG_TPM_ST33ZP24_SPI 1269 Support for STMicroelectronics ST33ZP24 SPI devices. 1270 Requires TPM_ST33ZP24 and SPI. 1271 1272 CONFIG_TPM_ATMEL_TWI 1273 Support for Atmel TWI TPM device. Requires I2C support. 1274 1275 CONFIG_TPM_TIS_LPC 1276 Support for generic parallel port TPM devices. Only one device 1277 per system is supported at this time. 1278 1279 CONFIG_TPM_TIS_BASE_ADDRESS 1280 Base address where the generic TPM device is mapped 1281 to. Contemporary x86 systems usually map it at 1282 0xfed40000. 1283 1284 CONFIG_CMD_TPM 1285 Add tpm monitor functions. 1286 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1287 provides monitor access to authorized functions. 1288 1289 CONFIG_TPM 1290 Define this to enable the TPM support library which provides 1291 functional interfaces to some TPM commands. 1292 Requires support for a TPM device. 1293 1294 CONFIG_TPM_AUTH_SESSIONS 1295 Define this to enable authorized functions in the TPM library. 1296 Requires CONFIG_TPM and CONFIG_SHA1. 1297 1298- USB Support: 1299 At the moment only the UHCI host controller is 1300 supported (PIP405, MIP405, MPC5200); define 1301 CONFIG_USB_UHCI to enable it. 1302 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1303 and define CONFIG_USB_STORAGE to enable the USB 1304 storage devices. 1305 Note: 1306 Supported are USB Keyboards and USB Floppy drives 1307 (TEAC FD-05PUB). 1308 MPC5200 USB requires additional defines: 1309 CONFIG_USB_CLOCK 1310 for 528 MHz Clock: 0x0001bbbb 1311 CONFIG_PSC3_USB 1312 for USB on PSC3 1313 CONFIG_USB_CONFIG 1314 for differential drivers: 0x00001000 1315 for single ended drivers: 0x00005000 1316 for differential drivers on PSC3: 0x00000100 1317 for single ended drivers on PSC3: 0x00004100 1318 CONFIG_SYS_USB_EVENT_POLL 1319 May be defined to allow interrupt polling 1320 instead of using asynchronous interrupts 1321 1322 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1323 txfilltuning field in the EHCI controller on reset. 1324 1325 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1326 HW module registers. 1327 1328- USB Device: 1329 Define the below if you wish to use the USB console. 1330 Once firmware is rebuilt from a serial console issue the 1331 command "setenv stdin usbtty; setenv stdout usbtty" and 1332 attach your USB cable. The Unix command "dmesg" should print 1333 it has found a new device. The environment variable usbtty 1334 can be set to gserial or cdc_acm to enable your device to 1335 appear to a USB host as a Linux gserial device or a 1336 Common Device Class Abstract Control Model serial device. 1337 If you select usbtty = gserial you should be able to enumerate 1338 a Linux host by 1339 # modprobe usbserial vendor=0xVendorID product=0xProductID 1340 else if using cdc_acm, simply setting the environment 1341 variable usbtty to be cdc_acm should suffice. The following 1342 might be defined in YourBoardName.h 1343 1344 CONFIG_USB_DEVICE 1345 Define this to build a UDC device 1346 1347 CONFIG_USB_TTY 1348 Define this to have a tty type of device available to 1349 talk to the UDC device 1350 1351 CONFIG_USBD_HS 1352 Define this to enable the high speed support for usb 1353 device and usbtty. If this feature is enabled, a routine 1354 int is_usbd_high_speed(void) 1355 also needs to be defined by the driver to dynamically poll 1356 whether the enumeration has succeded at high speed or full 1357 speed. 1358 1359 CONFIG_SYS_CONSOLE_IS_IN_ENV 1360 Define this if you want stdin, stdout &/or stderr to 1361 be set to usbtty. 1362 1363 mpc8xx: 1364 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1365 Derive USB clock from external clock "blah" 1366 - CONFIG_SYS_USB_EXTC_CLK 0x02 1367 1368 If you have a USB-IF assigned VendorID then you may wish to 1369 define your own vendor specific values either in BoardName.h 1370 or directly in usbd_vendor_info.h. If you don't define 1371 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1372 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1373 should pretend to be a Linux device to it's target host. 1374 1375 CONFIG_USBD_MANUFACTURER 1376 Define this string as the name of your company for 1377 - CONFIG_USBD_MANUFACTURER "my company" 1378 1379 CONFIG_USBD_PRODUCT_NAME 1380 Define this string as the name of your product 1381 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1382 1383 CONFIG_USBD_VENDORID 1384 Define this as your assigned Vendor ID from the USB 1385 Implementors Forum. This *must* be a genuine Vendor ID 1386 to avoid polluting the USB namespace. 1387 - CONFIG_USBD_VENDORID 0xFFFF 1388 1389 CONFIG_USBD_PRODUCTID 1390 Define this as the unique Product ID 1391 for your device 1392 - CONFIG_USBD_PRODUCTID 0xFFFF 1393 1394- ULPI Layer Support: 1395 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1396 the generic ULPI layer. The generic layer accesses the ULPI PHY 1397 via the platform viewport, so you need both the genric layer and 1398 the viewport enabled. Currently only Chipidea/ARC based 1399 viewport is supported. 1400 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1401 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1402 If your ULPI phy needs a different reference clock than the 1403 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1404 the appropriate value in Hz. 1405 1406- MMC Support: 1407 The MMC controller on the Intel PXA is supported. To 1408 enable this define CONFIG_MMC. The MMC can be 1409 accessed from the boot prompt by mapping the device 1410 to physical memory similar to flash. Command line is 1411 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1412 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1413 1414 CONFIG_SH_MMCIF 1415 Support for Renesas on-chip MMCIF controller 1416 1417 CONFIG_SH_MMCIF_ADDR 1418 Define the base address of MMCIF registers 1419 1420 CONFIG_SH_MMCIF_CLK 1421 Define the clock frequency for MMCIF 1422 1423 CONFIG_SUPPORT_EMMC_BOOT 1424 Enable some additional features of the eMMC boot partitions. 1425 1426 CONFIG_SUPPORT_EMMC_RPMB 1427 Enable the commands for reading, writing and programming the 1428 key for the Replay Protection Memory Block partition in eMMC. 1429 1430- USB Device Firmware Update (DFU) class support: 1431 CONFIG_USB_FUNCTION_DFU 1432 This enables the USB portion of the DFU USB class 1433 1434 CONFIG_CMD_DFU 1435 This enables the command "dfu" which is used to have 1436 U-Boot create a DFU class device via USB. This command 1437 requires that the "dfu_alt_info" environment variable be 1438 set and define the alt settings to expose to the host. 1439 1440 CONFIG_DFU_MMC 1441 This enables support for exposing (e)MMC devices via DFU. 1442 1443 CONFIG_DFU_NAND 1444 This enables support for exposing NAND devices via DFU. 1445 1446 CONFIG_DFU_RAM 1447 This enables support for exposing RAM via DFU. 1448 Note: DFU spec refer to non-volatile memory usage, but 1449 allow usages beyond the scope of spec - here RAM usage, 1450 one that would help mostly the developer. 1451 1452 CONFIG_SYS_DFU_DATA_BUF_SIZE 1453 Dfu transfer uses a buffer before writing data to the 1454 raw storage device. Make the size (in bytes) of this buffer 1455 configurable. The size of this buffer is also configurable 1456 through the "dfu_bufsiz" environment variable. 1457 1458 CONFIG_SYS_DFU_MAX_FILE_SIZE 1459 When updating files rather than the raw storage device, 1460 we use a static buffer to copy the file into and then write 1461 the buffer once we've been given the whole file. Define 1462 this to the maximum filesize (in bytes) for the buffer. 1463 Default is 4 MiB if undefined. 1464 1465 DFU_DEFAULT_POLL_TIMEOUT 1466 Poll timeout [ms], is the timeout a device can send to the 1467 host. The host must wait for this timeout before sending 1468 a subsequent DFU_GET_STATUS request to the device. 1469 1470 DFU_MANIFEST_POLL_TIMEOUT 1471 Poll timeout [ms], which the device sends to the host when 1472 entering dfuMANIFEST state. Host waits this timeout, before 1473 sending again an USB request to the device. 1474 1475- USB Device Android Fastboot support: 1476 CONFIG_USB_FUNCTION_FASTBOOT 1477 This enables the USB part of the fastboot gadget 1478 1479 CONFIG_CMD_FASTBOOT 1480 This enables the command "fastboot" which enables the Android 1481 fastboot mode for the platform's USB device. Fastboot is a USB 1482 protocol for downloading images, flashing and device control 1483 used on Android devices. 1484 See doc/README.android-fastboot for more information. 1485 1486 CONFIG_ANDROID_BOOT_IMAGE 1487 This enables support for booting images which use the Android 1488 image format header. 1489 1490 CONFIG_FASTBOOT_BUF_ADDR 1491 The fastboot protocol requires a large memory buffer for 1492 downloads. Define this to the starting RAM address to use for 1493 downloaded images. 1494 1495 CONFIG_FASTBOOT_BUF_SIZE 1496 The fastboot protocol requires a large memory buffer for 1497 downloads. This buffer should be as large as possible for a 1498 platform. Define this to the size available RAM for fastboot. 1499 1500 CONFIG_FASTBOOT_FLASH 1501 The fastboot protocol includes a "flash" command for writing 1502 the downloaded image to a non-volatile storage device. Define 1503 this to enable the "fastboot flash" command. 1504 1505 CONFIG_FASTBOOT_FLASH_MMC_DEV 1506 The fastboot "flash" command requires additional information 1507 regarding the non-volatile storage device. Define this to 1508 the eMMC device that fastboot should use to store the image. 1509 1510 CONFIG_FASTBOOT_GPT_NAME 1511 The fastboot "flash" command supports writing the downloaded 1512 image to the Protective MBR and the Primary GUID Partition 1513 Table. (Additionally, this downloaded image is post-processed 1514 to generate and write the Backup GUID Partition Table.) 1515 This occurs when the specified "partition name" on the 1516 "fastboot flash" command line matches this value. 1517 The default is "gpt" if undefined. 1518 1519 CONFIG_FASTBOOT_MBR_NAME 1520 The fastboot "flash" command supports writing the downloaded 1521 image to DOS MBR. 1522 This occurs when the "partition name" specified on the 1523 "fastboot flash" command line matches this value. 1524 If not defined the default value "mbr" is used. 1525 1526- Journaling Flash filesystem support: 1527 CONFIG_JFFS2_NAND 1528 Define these for a default partition on a NAND device 1529 1530 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1531 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1532 Define these for a default partition on a NOR device 1533 1534- FAT(File Allocation Table) filesystem write function support: 1535 CONFIG_FAT_WRITE 1536 1537 Define this to enable support for saving memory data as a 1538 file in FAT formatted partition. 1539 1540 This will also enable the command "fatwrite" enabling the 1541 user to write files to FAT. 1542 1543- FAT(File Allocation Table) filesystem cluster size: 1544 CONFIG_FS_FAT_MAX_CLUSTSIZE 1545 1546 Define the max cluster size for fat operations else 1547 a default value of 65536 will be defined. 1548 1549- Keyboard Support: 1550 See Kconfig help for available keyboard drivers. 1551 1552 CONFIG_KEYBOARD 1553 1554 Define this to enable a custom keyboard support. 1555 This simply calls drv_keyboard_init() which must be 1556 defined in your board-specific files. This option is deprecated 1557 and is only used by novena. For new boards, use driver model 1558 instead. 1559 1560- Video support: 1561 CONFIG_FSL_DIU_FB 1562 Enable the Freescale DIU video driver. Reference boards for 1563 SOCs that have a DIU should define this macro to enable DIU 1564 support, and should also define these other macros: 1565 1566 CONFIG_SYS_DIU_ADDR 1567 CONFIG_VIDEO 1568 CONFIG_CFB_CONSOLE 1569 CONFIG_VIDEO_SW_CURSOR 1570 CONFIG_VGA_AS_SINGLE_DEVICE 1571 CONFIG_VIDEO_LOGO 1572 CONFIG_VIDEO_BMP_LOGO 1573 1574 The DIU driver will look for the 'video-mode' environment 1575 variable, and if defined, enable the DIU as a console during 1576 boot. See the documentation file doc/README.video for a 1577 description of this variable. 1578 1579- LCD Support: CONFIG_LCD 1580 1581 Define this to enable LCD support (for output to LCD 1582 display); also select one of the supported displays 1583 by defining one of these: 1584 1585 CONFIG_ATMEL_LCD: 1586 1587 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1588 1589 CONFIG_NEC_NL6448AC33: 1590 1591 NEC NL6448AC33-18. Active, color, single scan. 1592 1593 CONFIG_NEC_NL6448BC20 1594 1595 NEC NL6448BC20-08. 6.5", 640x480. 1596 Active, color, single scan. 1597 1598 CONFIG_NEC_NL6448BC33_54 1599 1600 NEC NL6448BC33-54. 10.4", 640x480. 1601 Active, color, single scan. 1602 1603 CONFIG_SHARP_16x9 1604 1605 Sharp 320x240. Active, color, single scan. 1606 It isn't 16x9, and I am not sure what it is. 1607 1608 CONFIG_SHARP_LQ64D341 1609 1610 Sharp LQ64D341 display, 640x480. 1611 Active, color, single scan. 1612 1613 CONFIG_HLD1045 1614 1615 HLD1045 display, 640x480. 1616 Active, color, single scan. 1617 1618 CONFIG_OPTREX_BW 1619 1620 Optrex CBL50840-2 NF-FW 99 22 M5 1621 or 1622 Hitachi LMG6912RPFC-00T 1623 or 1624 Hitachi SP14Q002 1625 1626 320x240. Black & white. 1627 1628 CONFIG_LCD_ALIGNMENT 1629 1630 Normally the LCD is page-aligned (typically 4KB). If this is 1631 defined then the LCD will be aligned to this value instead. 1632 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1633 here, since it is cheaper to change data cache settings on 1634 a per-section basis. 1635 1636 1637 CONFIG_LCD_ROTATION 1638 1639 Sometimes, for example if the display is mounted in portrait 1640 mode or even if it's mounted landscape but rotated by 180degree, 1641 we need to rotate our content of the display relative to the 1642 framebuffer, so that user can read the messages which are 1643 printed out. 1644 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1645 initialized with a given rotation from "vl_rot" out of 1646 "vidinfo_t" which is provided by the board specific code. 1647 The value for vl_rot is coded as following (matching to 1648 fbcon=rotate:<n> linux-kernel commandline): 1649 0 = no rotation respectively 0 degree 1650 1 = 90 degree rotation 1651 2 = 180 degree rotation 1652 3 = 270 degree rotation 1653 1654 If CONFIG_LCD_ROTATION is not defined, the console will be 1655 initialized with 0degree rotation. 1656 1657 CONFIG_LCD_BMP_RLE8 1658 1659 Support drawing of RLE8-compressed bitmaps on the LCD. 1660 1661 CONFIG_I2C_EDID 1662 1663 Enables an 'i2c edid' command which can read EDID 1664 information over I2C from an attached LCD display. 1665 1666- Splash Screen Support: CONFIG_SPLASH_SCREEN 1667 1668 If this option is set, the environment is checked for 1669 a variable "splashimage". If found, the usual display 1670 of logo, copyright and system information on the LCD 1671 is suppressed and the BMP image at the address 1672 specified in "splashimage" is loaded instead. The 1673 console is redirected to the "nulldev", too. This 1674 allows for a "silent" boot where a splash screen is 1675 loaded very quickly after power-on. 1676 1677 CONFIG_SPLASHIMAGE_GUARD 1678 1679 If this option is set, then U-Boot will prevent the environment 1680 variable "splashimage" from being set to a problematic address 1681 (see doc/README.displaying-bmps). 1682 This option is useful for targets where, due to alignment 1683 restrictions, an improperly aligned BMP image will cause a data 1684 abort. If you think you will not have problems with unaligned 1685 accesses (for example because your toolchain prevents them) 1686 there is no need to set this option. 1687 1688 CONFIG_SPLASH_SCREEN_ALIGN 1689 1690 If this option is set the splash image can be freely positioned 1691 on the screen. Environment variable "splashpos" specifies the 1692 position as "x,y". If a positive number is given it is used as 1693 number of pixel from left/top. If a negative number is given it 1694 is used as number of pixel from right/bottom. You can also 1695 specify 'm' for centering the image. 1696 1697 Example: 1698 setenv splashpos m,m 1699 => image at center of screen 1700 1701 setenv splashpos 30,20 1702 => image at x = 30 and y = 20 1703 1704 setenv splashpos -10,m 1705 => vertically centered image 1706 at x = dspWidth - bmpWidth - 9 1707 1708- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1709 1710 If this option is set, additionally to standard BMP 1711 images, gzipped BMP images can be displayed via the 1712 splashscreen support or the bmp command. 1713 1714- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1715 1716 If this option is set, 8-bit RLE compressed BMP images 1717 can be displayed via the splashscreen support or the 1718 bmp command. 1719 1720- Compression support: 1721 CONFIG_GZIP 1722 1723 Enabled by default to support gzip compressed images. 1724 1725 CONFIG_BZIP2 1726 1727 If this option is set, support for bzip2 compressed 1728 images is included. If not, only uncompressed and gzip 1729 compressed images are supported. 1730 1731 NOTE: the bzip2 algorithm requires a lot of RAM, so 1732 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1733 be at least 4MB. 1734 1735 CONFIG_LZMA 1736 1737 If this option is set, support for lzma compressed 1738 images is included. 1739 1740 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1741 requires an amount of dynamic memory that is given by the 1742 formula: 1743 1744 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1745 1746 Where lc and lp stand for, respectively, Literal context bits 1747 and Literal pos bits. 1748 1749 This value is upper-bounded by 14MB in the worst case. Anyway, 1750 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1751 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1752 a very small buffer. 1753 1754 Use the lzmainfo tool to determinate the lc and lp values and 1755 then calculate the amount of needed dynamic memory (ensuring 1756 the appropriate CONFIG_SYS_MALLOC_LEN value). 1757 1758 CONFIG_LZO 1759 1760 If this option is set, support for LZO compressed images 1761 is included. 1762 1763- MII/PHY support: 1764 CONFIG_PHY_ADDR 1765 1766 The address of PHY on MII bus. 1767 1768 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1769 1770 The clock frequency of the MII bus 1771 1772 CONFIG_PHY_GIGE 1773 1774 If this option is set, support for speed/duplex 1775 detection of gigabit PHY is included. 1776 1777 CONFIG_PHY_RESET_DELAY 1778 1779 Some PHY like Intel LXT971A need extra delay after 1780 reset before any MII register access is possible. 1781 For such PHY, set this option to the usec delay 1782 required. (minimum 300usec for LXT971A) 1783 1784 CONFIG_PHY_CMD_DELAY (ppc4xx) 1785 1786 Some PHY like Intel LXT971A need extra delay after 1787 command issued before MII status register can be read 1788 1789- IP address: 1790 CONFIG_IPADDR 1791 1792 Define a default value for the IP address to use for 1793 the default Ethernet interface, in case this is not 1794 determined through e.g. bootp. 1795 (Environment variable "ipaddr") 1796 1797- Server IP address: 1798 CONFIG_SERVERIP 1799 1800 Defines a default value for the IP address of a TFTP 1801 server to contact when using the "tftboot" command. 1802 (Environment variable "serverip") 1803 1804 CONFIG_KEEP_SERVERADDR 1805 1806 Keeps the server's MAC address, in the env 'serveraddr' 1807 for passing to bootargs (like Linux's netconsole option) 1808 1809- Gateway IP address: 1810 CONFIG_GATEWAYIP 1811 1812 Defines a default value for the IP address of the 1813 default router where packets to other networks are 1814 sent to. 1815 (Environment variable "gatewayip") 1816 1817- Subnet mask: 1818 CONFIG_NETMASK 1819 1820 Defines a default value for the subnet mask (or 1821 routing prefix) which is used to determine if an IP 1822 address belongs to the local subnet or needs to be 1823 forwarded through a router. 1824 (Environment variable "netmask") 1825 1826- Multicast TFTP Mode: 1827 CONFIG_MCAST_TFTP 1828 1829 Defines whether you want to support multicast TFTP as per 1830 rfc-2090; for example to work with atftp. Lets lots of targets 1831 tftp down the same boot image concurrently. Note: the Ethernet 1832 driver in use must provide a function: mcast() to join/leave a 1833 multicast group. 1834 1835- BOOTP Recovery Mode: 1836 CONFIG_BOOTP_RANDOM_DELAY 1837 1838 If you have many targets in a network that try to 1839 boot using BOOTP, you may want to avoid that all 1840 systems send out BOOTP requests at precisely the same 1841 moment (which would happen for instance at recovery 1842 from a power failure, when all systems will try to 1843 boot, thus flooding the BOOTP server. Defining 1844 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1845 inserted before sending out BOOTP requests. The 1846 following delays are inserted then: 1847 1848 1st BOOTP request: delay 0 ... 1 sec 1849 2nd BOOTP request: delay 0 ... 2 sec 1850 3rd BOOTP request: delay 0 ... 4 sec 1851 4th and following 1852 BOOTP requests: delay 0 ... 8 sec 1853 1854 CONFIG_BOOTP_ID_CACHE_SIZE 1855 1856 BOOTP packets are uniquely identified using a 32-bit ID. The 1857 server will copy the ID from client requests to responses and 1858 U-Boot will use this to determine if it is the destination of 1859 an incoming response. Some servers will check that addresses 1860 aren't in use before handing them out (usually using an ARP 1861 ping) and therefore take up to a few hundred milliseconds to 1862 respond. Network congestion may also influence the time it 1863 takes for a response to make it back to the client. If that 1864 time is too long, U-Boot will retransmit requests. In order 1865 to allow earlier responses to still be accepted after these 1866 retransmissions, U-Boot's BOOTP client keeps a small cache of 1867 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1868 cache. The default is to keep IDs for up to four outstanding 1869 requests. Increasing this will allow U-Boot to accept offers 1870 from a BOOTP client in networks with unusually high latency. 1871 1872- DHCP Advanced Options: 1873 You can fine tune the DHCP functionality by defining 1874 CONFIG_BOOTP_* symbols: 1875 1876 CONFIG_BOOTP_SUBNETMASK 1877 CONFIG_BOOTP_GATEWAY 1878 CONFIG_BOOTP_HOSTNAME 1879 CONFIG_BOOTP_NISDOMAIN 1880 CONFIG_BOOTP_BOOTPATH 1881 CONFIG_BOOTP_BOOTFILESIZE 1882 CONFIG_BOOTP_DNS 1883 CONFIG_BOOTP_DNS2 1884 CONFIG_BOOTP_SEND_HOSTNAME 1885 CONFIG_BOOTP_NTPSERVER 1886 CONFIG_BOOTP_TIMEOFFSET 1887 CONFIG_BOOTP_VENDOREX 1888 CONFIG_BOOTP_MAY_FAIL 1889 1890 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1891 environment variable, not the BOOTP server. 1892 1893 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1894 after the configured retry count, the call will fail 1895 instead of starting over. This can be used to fail over 1896 to Link-local IP address configuration if the DHCP server 1897 is not available. 1898 1899 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1900 serverip from a DHCP server, it is possible that more 1901 than one DNS serverip is offered to the client. 1902 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1903 serverip will be stored in the additional environment 1904 variable "dnsip2". The first DNS serverip is always 1905 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1906 is defined. 1907 1908 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1909 to do a dynamic update of a DNS server. To do this, they 1910 need the hostname of the DHCP requester. 1911 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1912 of the "hostname" environment variable is passed as 1913 option 12 to the DHCP server. 1914 1915 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1916 1917 A 32bit value in microseconds for a delay between 1918 receiving a "DHCP Offer" and sending the "DHCP Request". 1919 This fixes a problem with certain DHCP servers that don't 1920 respond 100% of the time to a "DHCP request". E.g. On an 1921 AT91RM9200 processor running at 180MHz, this delay needed 1922 to be *at least* 15,000 usec before a Windows Server 2003 1923 DHCP server would reply 100% of the time. I recommend at 1924 least 50,000 usec to be safe. The alternative is to hope 1925 that one of the retries will be successful but note that 1926 the DHCP timeout and retry process takes a longer than 1927 this delay. 1928 1929 - Link-local IP address negotiation: 1930 Negotiate with other link-local clients on the local network 1931 for an address that doesn't require explicit configuration. 1932 This is especially useful if a DHCP server cannot be guaranteed 1933 to exist in all environments that the device must operate. 1934 1935 See doc/README.link-local for more information. 1936 1937 - CDP Options: 1938 CONFIG_CDP_DEVICE_ID 1939 1940 The device id used in CDP trigger frames. 1941 1942 CONFIG_CDP_DEVICE_ID_PREFIX 1943 1944 A two character string which is prefixed to the MAC address 1945 of the device. 1946 1947 CONFIG_CDP_PORT_ID 1948 1949 A printf format string which contains the ascii name of 1950 the port. Normally is set to "eth%d" which sets 1951 eth0 for the first Ethernet, eth1 for the second etc. 1952 1953 CONFIG_CDP_CAPABILITIES 1954 1955 A 32bit integer which indicates the device capabilities; 1956 0x00000010 for a normal host which does not forwards. 1957 1958 CONFIG_CDP_VERSION 1959 1960 An ascii string containing the version of the software. 1961 1962 CONFIG_CDP_PLATFORM 1963 1964 An ascii string containing the name of the platform. 1965 1966 CONFIG_CDP_TRIGGER 1967 1968 A 32bit integer sent on the trigger. 1969 1970 CONFIG_CDP_POWER_CONSUMPTION 1971 1972 A 16bit integer containing the power consumption of the 1973 device in .1 of milliwatts. 1974 1975 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1976 1977 A byte containing the id of the VLAN. 1978 1979- Status LED: CONFIG_LED_STATUS 1980 1981 Several configurations allow to display the current 1982 status using a LED. For instance, the LED will blink 1983 fast while running U-Boot code, stop blinking as 1984 soon as a reply to a BOOTP request was received, and 1985 start blinking slow once the Linux kernel is running 1986 (supported by a status LED driver in the Linux 1987 kernel). Defining CONFIG_LED_STATUS enables this 1988 feature in U-Boot. 1989 1990 Additional options: 1991 1992 CONFIG_LED_STATUS_GPIO 1993 The status LED can be connected to a GPIO pin. 1994 In such cases, the gpio_led driver can be used as a 1995 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 1996 to include the gpio_led driver in the U-Boot binary. 1997 1998 CONFIG_GPIO_LED_INVERTED_TABLE 1999 Some GPIO connected LEDs may have inverted polarity in which 2000 case the GPIO high value corresponds to LED off state and 2001 GPIO low value corresponds to LED on state. 2002 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2003 with a list of GPIO LEDs that have inverted polarity. 2004 2005- CAN Support: CONFIG_CAN_DRIVER 2006 2007 Defining CONFIG_CAN_DRIVER enables CAN driver support 2008 on those systems that support this (optional) 2009 feature, like the TQM8xxL modules. 2010 2011- I2C Support: CONFIG_SYS_I2C 2012 2013 This enable the NEW i2c subsystem, and will allow you to use 2014 i2c commands at the u-boot command line (as long as you set 2015 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2016 based realtime clock chips or other i2c devices. See 2017 common/cmd_i2c.c for a description of the command line 2018 interface. 2019 2020 ported i2c driver to the new framework: 2021 - drivers/i2c/soft_i2c.c: 2022 - activate first bus with CONFIG_SYS_I2C_SOFT define 2023 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2024 for defining speed and slave address 2025 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2026 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2027 for defining speed and slave address 2028 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2029 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2030 for defining speed and slave address 2031 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2032 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2033 for defining speed and slave address 2034 2035 - drivers/i2c/fsl_i2c.c: 2036 - activate i2c driver with CONFIG_SYS_I2C_FSL 2037 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2038 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2039 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2040 bus. 2041 - If your board supports a second fsl i2c bus, define 2042 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2043 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2044 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2045 second bus. 2046 2047 - drivers/i2c/tegra_i2c.c: 2048 - activate this driver with CONFIG_SYS_I2C_TEGRA 2049 - This driver adds 4 i2c buses with a fix speed from 2050 100000 and the slave addr 0! 2051 2052 - drivers/i2c/ppc4xx_i2c.c 2053 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2054 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2055 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2056 2057 - drivers/i2c/i2c_mxc.c 2058 - activate this driver with CONFIG_SYS_I2C_MXC 2059 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2060 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2061 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2062 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2063 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2064 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2065 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2066 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2067 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2068 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2069 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2070 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2071 If those defines are not set, default value is 100000 2072 for speed, and 0 for slave. 2073 2074 - drivers/i2c/rcar_i2c.c: 2075 - activate this driver with CONFIG_SYS_I2C_RCAR 2076 - This driver adds 4 i2c buses 2077 2078 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2079 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2080 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2081 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2082 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2083 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2084 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2085 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2086 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2087 2088 - drivers/i2c/sh_i2c.c: 2089 - activate this driver with CONFIG_SYS_I2C_SH 2090 - This driver adds from 2 to 5 i2c buses 2091 2092 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2093 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2094 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2095 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2096 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2097 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2098 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2099 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2100 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2101 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2102 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2103 2104 - drivers/i2c/omap24xx_i2c.c 2105 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2106 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2107 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2108 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2109 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2110 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2111 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2112 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2113 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2114 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2115 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2116 2117 - drivers/i2c/zynq_i2c.c 2118 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2119 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2120 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2121 2122 - drivers/i2c/s3c24x0_i2c.c: 2123 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2124 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2125 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2126 with a fix speed from 100000 and the slave addr 0! 2127 2128 - drivers/i2c/ihs_i2c.c 2129 - activate this driver with CONFIG_SYS_I2C_IHS 2130 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2131 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2132 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2133 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2134 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2135 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2136 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2137 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2138 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2139 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2140 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2141 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2142 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2143 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2144 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2145 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2146 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2147 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2148 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2149 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2150 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2151 2152 additional defines: 2153 2154 CONFIG_SYS_NUM_I2C_BUSES 2155 Hold the number of i2c buses you want to use. 2156 2157 CONFIG_SYS_I2C_DIRECT_BUS 2158 define this, if you don't use i2c muxes on your hardware. 2159 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2160 omit this define. 2161 2162 CONFIG_SYS_I2C_MAX_HOPS 2163 define how many muxes are maximal consecutively connected 2164 on one i2c bus. If you not use i2c muxes, omit this 2165 define. 2166 2167 CONFIG_SYS_I2C_BUSES 2168 hold a list of buses you want to use, only used if 2169 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2170 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2171 CONFIG_SYS_NUM_I2C_BUSES = 9: 2172 2173 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2174 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2175 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2176 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2177 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2178 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2179 {1, {I2C_NULL_HOP}}, \ 2180 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2181 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2182 } 2183 2184 which defines 2185 bus 0 on adapter 0 without a mux 2186 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2187 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2188 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2189 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2190 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2191 bus 6 on adapter 1 without a mux 2192 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2193 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2194 2195 If you do not have i2c muxes on your board, omit this define. 2196 2197- Legacy I2C Support: 2198 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2199 then the following macros need to be defined (examples are 2200 from include/configs/lwmon.h): 2201 2202 I2C_INIT 2203 2204 (Optional). Any commands necessary to enable the I2C 2205 controller or configure ports. 2206 2207 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2208 2209 I2C_PORT 2210 2211 (Only for MPC8260 CPU). The I/O port to use (the code 2212 assumes both bits are on the same port). Valid values 2213 are 0..3 for ports A..D. 2214 2215 I2C_ACTIVE 2216 2217 The code necessary to make the I2C data line active 2218 (driven). If the data line is open collector, this 2219 define can be null. 2220 2221 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2222 2223 I2C_TRISTATE 2224 2225 The code necessary to make the I2C data line tri-stated 2226 (inactive). If the data line is open collector, this 2227 define can be null. 2228 2229 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2230 2231 I2C_READ 2232 2233 Code that returns true if the I2C data line is high, 2234 false if it is low. 2235 2236 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2237 2238 I2C_SDA(bit) 2239 2240 If <bit> is true, sets the I2C data line high. If it 2241 is false, it clears it (low). 2242 2243 eg: #define I2C_SDA(bit) \ 2244 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2245 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2246 2247 I2C_SCL(bit) 2248 2249 If <bit> is true, sets the I2C clock line high. If it 2250 is false, it clears it (low). 2251 2252 eg: #define I2C_SCL(bit) \ 2253 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2254 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2255 2256 I2C_DELAY 2257 2258 This delay is invoked four times per clock cycle so this 2259 controls the rate of data transfer. The data rate thus 2260 is 1 / (I2C_DELAY * 4). Often defined to be something 2261 like: 2262 2263 #define I2C_DELAY udelay(2) 2264 2265 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2266 2267 If your arch supports the generic GPIO framework (asm/gpio.h), 2268 then you may alternatively define the two GPIOs that are to be 2269 used as SCL / SDA. Any of the previous I2C_xxx macros will 2270 have GPIO-based defaults assigned to them as appropriate. 2271 2272 You should define these to the GPIO value as given directly to 2273 the generic GPIO functions. 2274 2275 CONFIG_SYS_I2C_INIT_BOARD 2276 2277 When a board is reset during an i2c bus transfer 2278 chips might think that the current transfer is still 2279 in progress. On some boards it is possible to access 2280 the i2c SCLK line directly, either by using the 2281 processor pin as a GPIO or by having a second pin 2282 connected to the bus. If this option is defined a 2283 custom i2c_init_board() routine in boards/xxx/board.c 2284 is run early in the boot sequence. 2285 2286 CONFIG_I2C_MULTI_BUS 2287 2288 This option allows the use of multiple I2C buses, each of which 2289 must have a controller. At any point in time, only one bus is 2290 active. To switch to a different bus, use the 'i2c dev' command. 2291 Note that bus numbering is zero-based. 2292 2293 CONFIG_SYS_I2C_NOPROBES 2294 2295 This option specifies a list of I2C devices that will be skipped 2296 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2297 is set, specify a list of bus-device pairs. Otherwise, specify 2298 a 1D array of device addresses 2299 2300 e.g. 2301 #undef CONFIG_I2C_MULTI_BUS 2302 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2303 2304 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2305 2306 #define CONFIG_I2C_MULTI_BUS 2307 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2308 2309 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2310 2311 CONFIG_SYS_SPD_BUS_NUM 2312 2313 If defined, then this indicates the I2C bus number for DDR SPD. 2314 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2315 2316 CONFIG_SYS_RTC_BUS_NUM 2317 2318 If defined, then this indicates the I2C bus number for the RTC. 2319 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2320 2321 CONFIG_SOFT_I2C_READ_REPEATED_START 2322 2323 defining this will force the i2c_read() function in 2324 the soft_i2c driver to perform an I2C repeated start 2325 between writing the address pointer and reading the 2326 data. If this define is omitted the default behaviour 2327 of doing a stop-start sequence will be used. Most I2C 2328 devices can use either method, but some require one or 2329 the other. 2330 2331- SPI Support: CONFIG_SPI 2332 2333 Enables SPI driver (so far only tested with 2334 SPI EEPROM, also an instance works with Crystal A/D and 2335 D/As on the SACSng board) 2336 2337 CONFIG_SH_SPI 2338 2339 Enables the driver for SPI controller on SuperH. Currently 2340 only SH7757 is supported. 2341 2342 CONFIG_SOFT_SPI 2343 2344 Enables a software (bit-bang) SPI driver rather than 2345 using hardware support. This is a general purpose 2346 driver that only requires three general I/O port pins 2347 (two outputs, one input) to function. If this is 2348 defined, the board configuration must define several 2349 SPI configuration items (port pins to use, etc). For 2350 an example, see include/configs/sacsng.h. 2351 2352 CONFIG_HARD_SPI 2353 2354 Enables a hardware SPI driver for general-purpose reads 2355 and writes. As with CONFIG_SOFT_SPI, the board configuration 2356 must define a list of chip-select function pointers. 2357 Currently supported on some MPC8xxx processors. For an 2358 example, see include/configs/mpc8349emds.h. 2359 2360 CONFIG_MXC_SPI 2361 2362 Enables the driver for the SPI controllers on i.MX and MXC 2363 SoCs. Currently i.MX31/35/51 are supported. 2364 2365 CONFIG_SYS_SPI_MXC_WAIT 2366 Timeout for waiting until spi transfer completed. 2367 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2368 2369- FPGA Support: CONFIG_FPGA 2370 2371 Enables FPGA subsystem. 2372 2373 CONFIG_FPGA_<vendor> 2374 2375 Enables support for specific chip vendors. 2376 (ALTERA, XILINX) 2377 2378 CONFIG_FPGA_<family> 2379 2380 Enables support for FPGA family. 2381 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2382 2383 CONFIG_FPGA_COUNT 2384 2385 Specify the number of FPGA devices to support. 2386 2387 CONFIG_CMD_FPGA_LOADMK 2388 2389 Enable support for fpga loadmk command 2390 2391 CONFIG_CMD_FPGA_LOADP 2392 2393 Enable support for fpga loadp command - load partial bitstream 2394 2395 CONFIG_CMD_FPGA_LOADBP 2396 2397 Enable support for fpga loadbp command - load partial bitstream 2398 (Xilinx only) 2399 2400 CONFIG_SYS_FPGA_PROG_FEEDBACK 2401 2402 Enable printing of hash marks during FPGA configuration. 2403 2404 CONFIG_SYS_FPGA_CHECK_BUSY 2405 2406 Enable checks on FPGA configuration interface busy 2407 status by the configuration function. This option 2408 will require a board or device specific function to 2409 be written. 2410 2411 CONFIG_FPGA_DELAY 2412 2413 If defined, a function that provides delays in the FPGA 2414 configuration driver. 2415 2416 CONFIG_SYS_FPGA_CHECK_CTRLC 2417 Allow Control-C to interrupt FPGA configuration 2418 2419 CONFIG_SYS_FPGA_CHECK_ERROR 2420 2421 Check for configuration errors during FPGA bitfile 2422 loading. For example, abort during Virtex II 2423 configuration if the INIT_B line goes low (which 2424 indicated a CRC error). 2425 2426 CONFIG_SYS_FPGA_WAIT_INIT 2427 2428 Maximum time to wait for the INIT_B line to de-assert 2429 after PROB_B has been de-asserted during a Virtex II 2430 FPGA configuration sequence. The default time is 500 2431 ms. 2432 2433 CONFIG_SYS_FPGA_WAIT_BUSY 2434 2435 Maximum time to wait for BUSY to de-assert during 2436 Virtex II FPGA configuration. The default is 5 ms. 2437 2438 CONFIG_SYS_FPGA_WAIT_CONFIG 2439 2440 Time to wait after FPGA configuration. The default is 2441 200 ms. 2442 2443- Configuration Management: 2444 CONFIG_BUILD_TARGET 2445 2446 Some SoCs need special image types (e.g. U-Boot binary 2447 with a special header) as build targets. By defining 2448 CONFIG_BUILD_TARGET in the SoC / board header, this 2449 special image will be automatically built upon calling 2450 make / buildman. 2451 2452 CONFIG_IDENT_STRING 2453 2454 If defined, this string will be added to the U-Boot 2455 version information (U_BOOT_VERSION) 2456 2457- Vendor Parameter Protection: 2458 2459 U-Boot considers the values of the environment 2460 variables "serial#" (Board Serial Number) and 2461 "ethaddr" (Ethernet Address) to be parameters that 2462 are set once by the board vendor / manufacturer, and 2463 protects these variables from casual modification by 2464 the user. Once set, these variables are read-only, 2465 and write or delete attempts are rejected. You can 2466 change this behaviour: 2467 2468 If CONFIG_ENV_OVERWRITE is #defined in your config 2469 file, the write protection for vendor parameters is 2470 completely disabled. Anybody can change or delete 2471 these parameters. 2472 2473 Alternatively, if you define _both_ an ethaddr in the 2474 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2475 Ethernet address is installed in the environment, 2476 which can be changed exactly ONCE by the user. [The 2477 serial# is unaffected by this, i. e. it remains 2478 read-only.] 2479 2480 The same can be accomplished in a more flexible way 2481 for any variable by configuring the type of access 2482 to allow for those variables in the ".flags" variable 2483 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2484 2485- Protected RAM: 2486 CONFIG_PRAM 2487 2488 Define this variable to enable the reservation of 2489 "protected RAM", i. e. RAM which is not overwritten 2490 by U-Boot. Define CONFIG_PRAM to hold the number of 2491 kB you want to reserve for pRAM. You can overwrite 2492 this default value by defining an environment 2493 variable "pram" to the number of kB you want to 2494 reserve. Note that the board info structure will 2495 still show the full amount of RAM. If pRAM is 2496 reserved, a new environment variable "mem" will 2497 automatically be defined to hold the amount of 2498 remaining RAM in a form that can be passed as boot 2499 argument to Linux, for instance like that: 2500 2501 setenv bootargs ... mem=\${mem} 2502 saveenv 2503 2504 This way you can tell Linux not to use this memory, 2505 either, which results in a memory region that will 2506 not be affected by reboots. 2507 2508 *WARNING* If your board configuration uses automatic 2509 detection of the RAM size, you must make sure that 2510 this memory test is non-destructive. So far, the 2511 following board configurations are known to be 2512 "pRAM-clean": 2513 2514 IVMS8, IVML24, SPD8xx, TQM8xxL, 2515 HERMES, IP860, RPXlite, LWMON, 2516 FLAGADM, TQM8260 2517 2518- Access to physical memory region (> 4GB) 2519 Some basic support is provided for operations on memory not 2520 normally accessible to U-Boot - e.g. some architectures 2521 support access to more than 4GB of memory on 32-bit 2522 machines using physical address extension or similar. 2523 Define CONFIG_PHYSMEM to access this basic support, which 2524 currently only supports clearing the memory. 2525 2526- Error Recovery: 2527 CONFIG_PANIC_HANG 2528 2529 Define this variable to stop the system in case of a 2530 fatal error, so that you have to reset it manually. 2531 This is probably NOT a good idea for an embedded 2532 system where you want the system to reboot 2533 automatically as fast as possible, but it may be 2534 useful during development since you can try to debug 2535 the conditions that lead to the situation. 2536 2537 CONFIG_NET_RETRY_COUNT 2538 2539 This variable defines the number of retries for 2540 network operations like ARP, RARP, TFTP, or BOOTP 2541 before giving up the operation. If not defined, a 2542 default value of 5 is used. 2543 2544 CONFIG_ARP_TIMEOUT 2545 2546 Timeout waiting for an ARP reply in milliseconds. 2547 2548 CONFIG_NFS_TIMEOUT 2549 2550 Timeout in milliseconds used in NFS protocol. 2551 If you encounter "ERROR: Cannot umount" in nfs command, 2552 try longer timeout such as 2553 #define CONFIG_NFS_TIMEOUT 10000UL 2554 2555- Command Interpreter: 2556 CONFIG_AUTO_COMPLETE 2557 2558 Enable auto completion of commands using TAB. 2559 2560 CONFIG_SYS_PROMPT_HUSH_PS2 2561 2562 This defines the secondary prompt string, which is 2563 printed when the command interpreter needs more input 2564 to complete a command. Usually "> ". 2565 2566 Note: 2567 2568 In the current implementation, the local variables 2569 space and global environment variables space are 2570 separated. Local variables are those you define by 2571 simply typing `name=value'. To access a local 2572 variable later on, you have write `$name' or 2573 `${name}'; to execute the contents of a variable 2574 directly type `$name' at the command prompt. 2575 2576 Global environment variables are those you use 2577 setenv/printenv to work with. To run a command stored 2578 in such a variable, you need to use the run command, 2579 and you must not use the '$' sign to access them. 2580 2581 To store commands and special characters in a 2582 variable, please use double quotation marks 2583 surrounding the whole text of the variable, instead 2584 of the backslashes before semicolons and special 2585 symbols. 2586 2587- Command Line Editing and History: 2588 CONFIG_CMDLINE_EDITING 2589 2590 Enable editing and History functions for interactive 2591 command line input operations 2592 2593- Command Line PS1/PS2 support: 2594 CONFIG_CMDLINE_PS_SUPPORT 2595 2596 Enable support for changing the command prompt string 2597 at run-time. Only static string is supported so far. 2598 The string is obtained from environment variables PS1 2599 and PS2. 2600 2601- Default Environment: 2602 CONFIG_EXTRA_ENV_SETTINGS 2603 2604 Define this to contain any number of null terminated 2605 strings (variable = value pairs) that will be part of 2606 the default environment compiled into the boot image. 2607 2608 For example, place something like this in your 2609 board's config file: 2610 2611 #define CONFIG_EXTRA_ENV_SETTINGS \ 2612 "myvar1=value1\0" \ 2613 "myvar2=value2\0" 2614 2615 Warning: This method is based on knowledge about the 2616 internal format how the environment is stored by the 2617 U-Boot code. This is NOT an official, exported 2618 interface! Although it is unlikely that this format 2619 will change soon, there is no guarantee either. 2620 You better know what you are doing here. 2621 2622 Note: overly (ab)use of the default environment is 2623 discouraged. Make sure to check other ways to preset 2624 the environment like the "source" command or the 2625 boot command first. 2626 2627 CONFIG_ENV_VARS_UBOOT_CONFIG 2628 2629 Define this in order to add variables describing the 2630 U-Boot build configuration to the default environment. 2631 These will be named arch, cpu, board, vendor, and soc. 2632 2633 Enabling this option will cause the following to be defined: 2634 2635 - CONFIG_SYS_ARCH 2636 - CONFIG_SYS_CPU 2637 - CONFIG_SYS_BOARD 2638 - CONFIG_SYS_VENDOR 2639 - CONFIG_SYS_SOC 2640 2641 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2642 2643 Define this in order to add variables describing certain 2644 run-time determined information about the hardware to the 2645 environment. These will be named board_name, board_rev. 2646 2647 CONFIG_DELAY_ENVIRONMENT 2648 2649 Normally the environment is loaded when the board is 2650 initialised so that it is available to U-Boot. This inhibits 2651 that so that the environment is not available until 2652 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2653 this is instead controlled by the value of 2654 /config/load-environment. 2655 2656- DataFlash Support: 2657 CONFIG_HAS_DATAFLASH 2658 2659 Defining this option enables DataFlash features and 2660 allows to read/write in Dataflash via the standard 2661 commands cp, md... 2662 2663- Serial Flash support 2664 CONFIG_CMD_SF 2665 2666 Defining this option enables SPI flash commands 2667 'sf probe/read/write/erase/update'. 2668 2669 Usage requires an initial 'probe' to define the serial 2670 flash parameters, followed by read/write/erase/update 2671 commands. 2672 2673 The following defaults may be provided by the platform 2674 to handle the common case when only a single serial 2675 flash is present on the system. 2676 2677 CONFIG_SF_DEFAULT_BUS Bus identifier 2678 CONFIG_SF_DEFAULT_CS Chip-select 2679 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2680 CONFIG_SF_DEFAULT_SPEED in Hz 2681 2682 CONFIG_CMD_SF_TEST 2683 2684 Define this option to include a destructive SPI flash 2685 test ('sf test'). 2686 2687 CONFIG_SF_DUAL_FLASH Dual flash memories 2688 2689 Define this option to use dual flash support where two flash 2690 memories can be connected with a given cs line. 2691 Currently Xilinx Zynq qspi supports these type of connections. 2692 2693- SystemACE Support: 2694 CONFIG_SYSTEMACE 2695 2696 Adding this option adds support for Xilinx SystemACE 2697 chips attached via some sort of local bus. The address 2698 of the chip must also be defined in the 2699 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2700 2701 #define CONFIG_SYSTEMACE 2702 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2703 2704 When SystemACE support is added, the "ace" device type 2705 becomes available to the fat commands, i.e. fatls. 2706 2707- TFTP Fixed UDP Port: 2708 CONFIG_TFTP_PORT 2709 2710 If this is defined, the environment variable tftpsrcp 2711 is used to supply the TFTP UDP source port value. 2712 If tftpsrcp isn't defined, the normal pseudo-random port 2713 number generator is used. 2714 2715 Also, the environment variable tftpdstp is used to supply 2716 the TFTP UDP destination port value. If tftpdstp isn't 2717 defined, the normal port 69 is used. 2718 2719 The purpose for tftpsrcp is to allow a TFTP server to 2720 blindly start the TFTP transfer using the pre-configured 2721 target IP address and UDP port. This has the effect of 2722 "punching through" the (Windows XP) firewall, allowing 2723 the remainder of the TFTP transfer to proceed normally. 2724 A better solution is to properly configure the firewall, 2725 but sometimes that is not allowed. 2726 2727- Hashing support: 2728 CONFIG_CMD_HASH 2729 2730 This enables a generic 'hash' command which can produce 2731 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2732 2733 CONFIG_HASH_VERIFY 2734 2735 Enable the hash verify command (hash -v). This adds to code 2736 size a little. 2737 2738 Note: There is also a sha1sum command, which should perhaps 2739 be deprecated in favour of 'hash sha1'. 2740 2741- Freescale i.MX specific commands: 2742 CONFIG_CMD_HDMIDETECT 2743 This enables 'hdmidet' command which returns true if an 2744 HDMI monitor is detected. This command is i.MX 6 specific. 2745 2746- bootcount support: 2747 CONFIG_BOOTCOUNT_LIMIT 2748 2749 This enables the bootcounter support, see: 2750 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2751 2752 CONFIG_AT91SAM9XE 2753 enable special bootcounter support on at91sam9xe based boards. 2754 CONFIG_SOC_DA8XX 2755 enable special bootcounter support on da850 based boards. 2756 CONFIG_BOOTCOUNT_RAM 2757 enable support for the bootcounter in RAM 2758 CONFIG_BOOTCOUNT_I2C 2759 enable support for the bootcounter on an i2c (like RTC) device. 2760 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2761 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2762 the bootcounter. 2763 CONFIG_BOOTCOUNT_ALEN = address len 2764 2765- Show boot progress: 2766 CONFIG_SHOW_BOOT_PROGRESS 2767 2768 Defining this option allows to add some board- 2769 specific code (calling a user-provided function 2770 "show_boot_progress(int)") that enables you to show 2771 the system's boot progress on some display (for 2772 example, some LED's) on your board. At the moment, 2773 the following checkpoints are implemented: 2774 2775 2776Legacy uImage format: 2777 2778 Arg Where When 2779 1 common/cmd_bootm.c before attempting to boot an image 2780 -1 common/cmd_bootm.c Image header has bad magic number 2781 2 common/cmd_bootm.c Image header has correct magic number 2782 -2 common/cmd_bootm.c Image header has bad checksum 2783 3 common/cmd_bootm.c Image header has correct checksum 2784 -3 common/cmd_bootm.c Image data has bad checksum 2785 4 common/cmd_bootm.c Image data has correct checksum 2786 -4 common/cmd_bootm.c Image is for unsupported architecture 2787 5 common/cmd_bootm.c Architecture check OK 2788 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2789 6 common/cmd_bootm.c Image Type check OK 2790 -6 common/cmd_bootm.c gunzip uncompression error 2791 -7 common/cmd_bootm.c Unimplemented compression type 2792 7 common/cmd_bootm.c Uncompression OK 2793 8 common/cmd_bootm.c No uncompress/copy overwrite error 2794 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2795 2796 9 common/image.c Start initial ramdisk verification 2797 -10 common/image.c Ramdisk header has bad magic number 2798 -11 common/image.c Ramdisk header has bad checksum 2799 10 common/image.c Ramdisk header is OK 2800 -12 common/image.c Ramdisk data has bad checksum 2801 11 common/image.c Ramdisk data has correct checksum 2802 12 common/image.c Ramdisk verification complete, start loading 2803 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2804 13 common/image.c Start multifile image verification 2805 14 common/image.c No initial ramdisk, no multifile, continue. 2806 2807 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2808 2809 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2810 -31 post/post.c POST test failed, detected by post_output_backlog() 2811 -32 post/post.c POST test failed, detected by post_run_single() 2812 2813 34 common/cmd_doc.c before loading a Image from a DOC device 2814 -35 common/cmd_doc.c Bad usage of "doc" command 2815 35 common/cmd_doc.c correct usage of "doc" command 2816 -36 common/cmd_doc.c No boot device 2817 36 common/cmd_doc.c correct boot device 2818 -37 common/cmd_doc.c Unknown Chip ID on boot device 2819 37 common/cmd_doc.c correct chip ID found, device available 2820 -38 common/cmd_doc.c Read Error on boot device 2821 38 common/cmd_doc.c reading Image header from DOC device OK 2822 -39 common/cmd_doc.c Image header has bad magic number 2823 39 common/cmd_doc.c Image header has correct magic number 2824 -40 common/cmd_doc.c Error reading Image from DOC device 2825 40 common/cmd_doc.c Image header has correct magic number 2826 41 common/cmd_ide.c before loading a Image from a IDE device 2827 -42 common/cmd_ide.c Bad usage of "ide" command 2828 42 common/cmd_ide.c correct usage of "ide" command 2829 -43 common/cmd_ide.c No boot device 2830 43 common/cmd_ide.c boot device found 2831 -44 common/cmd_ide.c Device not available 2832 44 common/cmd_ide.c Device available 2833 -45 common/cmd_ide.c wrong partition selected 2834 45 common/cmd_ide.c partition selected 2835 -46 common/cmd_ide.c Unknown partition table 2836 46 common/cmd_ide.c valid partition table found 2837 -47 common/cmd_ide.c Invalid partition type 2838 47 common/cmd_ide.c correct partition type 2839 -48 common/cmd_ide.c Error reading Image Header on boot device 2840 48 common/cmd_ide.c reading Image Header from IDE device OK 2841 -49 common/cmd_ide.c Image header has bad magic number 2842 49 common/cmd_ide.c Image header has correct magic number 2843 -50 common/cmd_ide.c Image header has bad checksum 2844 50 common/cmd_ide.c Image header has correct checksum 2845 -51 common/cmd_ide.c Error reading Image from IDE device 2846 51 common/cmd_ide.c reading Image from IDE device OK 2847 52 common/cmd_nand.c before loading a Image from a NAND device 2848 -53 common/cmd_nand.c Bad usage of "nand" command 2849 53 common/cmd_nand.c correct usage of "nand" command 2850 -54 common/cmd_nand.c No boot device 2851 54 common/cmd_nand.c boot device found 2852 -55 common/cmd_nand.c Unknown Chip ID on boot device 2853 55 common/cmd_nand.c correct chip ID found, device available 2854 -56 common/cmd_nand.c Error reading Image Header on boot device 2855 56 common/cmd_nand.c reading Image Header from NAND device OK 2856 -57 common/cmd_nand.c Image header has bad magic number 2857 57 common/cmd_nand.c Image header has correct magic number 2858 -58 common/cmd_nand.c Error reading Image from NAND device 2859 58 common/cmd_nand.c reading Image from NAND device OK 2860 2861 -60 common/env_common.c Environment has a bad CRC, using default 2862 2863 64 net/eth.c starting with Ethernet configuration. 2864 -64 net/eth.c no Ethernet found. 2865 65 net/eth.c Ethernet found. 2866 2867 -80 common/cmd_net.c usage wrong 2868 80 common/cmd_net.c before calling net_loop() 2869 -81 common/cmd_net.c some error in net_loop() occurred 2870 81 common/cmd_net.c net_loop() back without error 2871 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2872 82 common/cmd_net.c trying automatic boot 2873 83 common/cmd_net.c running "source" command 2874 -83 common/cmd_net.c some error in automatic boot or "source" command 2875 84 common/cmd_net.c end without errors 2876 2877FIT uImage format: 2878 2879 Arg Where When 2880 100 common/cmd_bootm.c Kernel FIT Image has correct format 2881 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2882 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2883 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2884 102 common/cmd_bootm.c Kernel unit name specified 2885 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2886 103 common/cmd_bootm.c Found configuration node 2887 104 common/cmd_bootm.c Got kernel subimage node offset 2888 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2889 105 common/cmd_bootm.c Kernel subimage hash verification OK 2890 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2891 106 common/cmd_bootm.c Architecture check OK 2892 -106 common/cmd_bootm.c Kernel subimage has wrong type 2893 107 common/cmd_bootm.c Kernel subimage type OK 2894 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2895 108 common/cmd_bootm.c Got kernel subimage data/size 2896 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2897 -109 common/cmd_bootm.c Can't get kernel subimage type 2898 -110 common/cmd_bootm.c Can't get kernel subimage comp 2899 -111 common/cmd_bootm.c Can't get kernel subimage os 2900 -112 common/cmd_bootm.c Can't get kernel subimage load address 2901 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2902 2903 120 common/image.c Start initial ramdisk verification 2904 -120 common/image.c Ramdisk FIT image has incorrect format 2905 121 common/image.c Ramdisk FIT image has correct format 2906 122 common/image.c No ramdisk subimage unit name, using configuration 2907 -122 common/image.c Can't get configuration for ramdisk subimage 2908 123 common/image.c Ramdisk unit name specified 2909 -124 common/image.c Can't get ramdisk subimage node offset 2910 125 common/image.c Got ramdisk subimage node offset 2911 -125 common/image.c Ramdisk subimage hash verification failed 2912 126 common/image.c Ramdisk subimage hash verification OK 2913 -126 common/image.c Ramdisk subimage for unsupported architecture 2914 127 common/image.c Architecture check OK 2915 -127 common/image.c Can't get ramdisk subimage data/size 2916 128 common/image.c Got ramdisk subimage data/size 2917 129 common/image.c Can't get ramdisk load address 2918 -129 common/image.c Got ramdisk load address 2919 2920 -130 common/cmd_doc.c Incorrect FIT image format 2921 131 common/cmd_doc.c FIT image format OK 2922 2923 -140 common/cmd_ide.c Incorrect FIT image format 2924 141 common/cmd_ide.c FIT image format OK 2925 2926 -150 common/cmd_nand.c Incorrect FIT image format 2927 151 common/cmd_nand.c FIT image format OK 2928 2929- legacy image format: 2930 CONFIG_IMAGE_FORMAT_LEGACY 2931 enables the legacy image format support in U-Boot. 2932 2933 Default: 2934 enabled if CONFIG_FIT_SIGNATURE is not defined. 2935 2936 CONFIG_DISABLE_IMAGE_LEGACY 2937 disable the legacy image format 2938 2939 This define is introduced, as the legacy image format is 2940 enabled per default for backward compatibility. 2941 2942- Standalone program support: 2943 CONFIG_STANDALONE_LOAD_ADDR 2944 2945 This option defines a board specific value for the 2946 address where standalone program gets loaded, thus 2947 overwriting the architecture dependent default 2948 settings. 2949 2950- Frame Buffer Address: 2951 CONFIG_FB_ADDR 2952 2953 Define CONFIG_FB_ADDR if you want to use specific 2954 address for frame buffer. This is typically the case 2955 when using a graphics controller has separate video 2956 memory. U-Boot will then place the frame buffer at 2957 the given address instead of dynamically reserving it 2958 in system RAM by calling lcd_setmem(), which grabs 2959 the memory for the frame buffer depending on the 2960 configured panel size. 2961 2962 Please see board_init_f function. 2963 2964- Automatic software updates via TFTP server 2965 CONFIG_UPDATE_TFTP 2966 CONFIG_UPDATE_TFTP_CNT_MAX 2967 CONFIG_UPDATE_TFTP_MSEC_MAX 2968 2969 These options enable and control the auto-update feature; 2970 for a more detailed description refer to doc/README.update. 2971 2972- MTD Support (mtdparts command, UBI support) 2973 CONFIG_MTD_DEVICE 2974 2975 Adds the MTD device infrastructure from the Linux kernel. 2976 Needed for mtdparts command support. 2977 2978 CONFIG_MTD_PARTITIONS 2979 2980 Adds the MTD partitioning infrastructure from the Linux 2981 kernel. Needed for UBI support. 2982 2983- UBI support 2984 CONFIG_CMD_UBI 2985 2986 Adds commands for interacting with MTD partitions formatted 2987 with the UBI flash translation layer 2988 2989 Requires also defining CONFIG_RBTREE 2990 2991 CONFIG_UBI_SILENCE_MSG 2992 2993 Make the verbose messages from UBI stop printing. This leaves 2994 warnings and errors enabled. 2995 2996 2997 CONFIG_MTD_UBI_WL_THRESHOLD 2998 This parameter defines the maximum difference between the highest 2999 erase counter value and the lowest erase counter value of eraseblocks 3000 of UBI devices. When this threshold is exceeded, UBI starts performing 3001 wear leveling by means of moving data from eraseblock with low erase 3002 counter to eraseblocks with high erase counter. 3003 3004 The default value should be OK for SLC NAND flashes, NOR flashes and 3005 other flashes which have eraseblock life-cycle 100000 or more. 3006 However, in case of MLC NAND flashes which typically have eraseblock 3007 life-cycle less than 10000, the threshold should be lessened (e.g., 3008 to 128 or 256, although it does not have to be power of 2). 3009 3010 default: 4096 3011 3012 CONFIG_MTD_UBI_BEB_LIMIT 3013 This option specifies the maximum bad physical eraseblocks UBI 3014 expects on the MTD device (per 1024 eraseblocks). If the 3015 underlying flash does not admit of bad eraseblocks (e.g. NOR 3016 flash), this value is ignored. 3017 3018 NAND datasheets often specify the minimum and maximum NVM 3019 (Number of Valid Blocks) for the flashes' endurance lifetime. 3020 The maximum expected bad eraseblocks per 1024 eraseblocks 3021 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3022 which gives 20 for most NANDs (MaxNVB is basically the total 3023 count of eraseblocks on the chip). 3024 3025 To put it differently, if this value is 20, UBI will try to 3026 reserve about 1.9% of physical eraseblocks for bad blocks 3027 handling. And that will be 1.9% of eraseblocks on the entire 3028 NAND chip, not just the MTD partition UBI attaches. This means 3029 that if you have, say, a NAND flash chip admits maximum 40 bad 3030 eraseblocks, and it is split on two MTD partitions of the same 3031 size, UBI will reserve 40 eraseblocks when attaching a 3032 partition. 3033 3034 default: 20 3035 3036 CONFIG_MTD_UBI_FASTMAP 3037 Fastmap is a mechanism which allows attaching an UBI device 3038 in nearly constant time. Instead of scanning the whole MTD device it 3039 only has to locate a checkpoint (called fastmap) on the device. 3040 The on-flash fastmap contains all information needed to attach 3041 the device. Using fastmap makes only sense on large devices where 3042 attaching by scanning takes long. UBI will not automatically install 3043 a fastmap on old images, but you can set the UBI parameter 3044 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3045 that fastmap-enabled images are still usable with UBI implementations 3046 without fastmap support. On typical flash devices the whole fastmap 3047 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3048 3049 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3050 Set this parameter to enable fastmap automatically on images 3051 without a fastmap. 3052 default: 0 3053 3054 CONFIG_MTD_UBI_FM_DEBUG 3055 Enable UBI fastmap debug 3056 default: 0 3057 3058- UBIFS support 3059 CONFIG_CMD_UBIFS 3060 3061 Adds commands for interacting with UBI volumes formatted as 3062 UBIFS. UBIFS is read-only in u-boot. 3063 3064 Requires UBI support as well as CONFIG_LZO 3065 3066 CONFIG_UBIFS_SILENCE_MSG 3067 3068 Make the verbose messages from UBIFS stop printing. This leaves 3069 warnings and errors enabled. 3070 3071- SPL framework 3072 CONFIG_SPL 3073 Enable building of SPL globally. 3074 3075 CONFIG_SPL_LDSCRIPT 3076 LDSCRIPT for linking the SPL binary. 3077 3078 CONFIG_SPL_MAX_FOOTPRINT 3079 Maximum size in memory allocated to the SPL, BSS included. 3080 When defined, the linker checks that the actual memory 3081 used by SPL from _start to __bss_end does not exceed it. 3082 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3083 must not be both defined at the same time. 3084 3085 CONFIG_SPL_MAX_SIZE 3086 Maximum size of the SPL image (text, data, rodata, and 3087 linker lists sections), BSS excluded. 3088 When defined, the linker checks that the actual size does 3089 not exceed it. 3090 3091 CONFIG_SPL_TEXT_BASE 3092 TEXT_BASE for linking the SPL binary. 3093 3094 CONFIG_SPL_RELOC_TEXT_BASE 3095 Address to relocate to. If unspecified, this is equal to 3096 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3097 3098 CONFIG_SPL_BSS_START_ADDR 3099 Link address for the BSS within the SPL binary. 3100 3101 CONFIG_SPL_BSS_MAX_SIZE 3102 Maximum size in memory allocated to the SPL BSS. 3103 When defined, the linker checks that the actual memory used 3104 by SPL from __bss_start to __bss_end does not exceed it. 3105 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3106 must not be both defined at the same time. 3107 3108 CONFIG_SPL_STACK 3109 Adress of the start of the stack SPL will use 3110 3111 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3112 When defined, SPL will panic() if the image it has 3113 loaded does not have a signature. 3114 Defining this is useful when code which loads images 3115 in SPL cannot guarantee that absolutely all read errors 3116 will be caught. 3117 An example is the LPC32XX MLC NAND driver, which will 3118 consider that a completely unreadable NAND block is bad, 3119 and thus should be skipped silently. 3120 3121 CONFIG_SPL_RELOC_STACK 3122 Adress of the start of the stack SPL will use after 3123 relocation. If unspecified, this is equal to 3124 CONFIG_SPL_STACK. 3125 3126 CONFIG_SYS_SPL_MALLOC_START 3127 Starting address of the malloc pool used in SPL. 3128 When this option is set the full malloc is used in SPL and 3129 it is set up by spl_init() and before that, the simple malloc() 3130 can be used if CONFIG_SYS_MALLOC_F is defined. 3131 3132 CONFIG_SYS_SPL_MALLOC_SIZE 3133 The size of the malloc pool used in SPL. 3134 3135 CONFIG_SPL_FRAMEWORK 3136 Enable the SPL framework under common/. This framework 3137 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3138 NAND loading of the Linux Kernel. 3139 3140 CONFIG_SPL_OS_BOOT 3141 Enable booting directly to an OS from SPL. 3142 See also: doc/README.falcon 3143 3144 CONFIG_SPL_DISPLAY_PRINT 3145 For ARM, enable an optional function to print more information 3146 about the running system. 3147 3148 CONFIG_SPL_INIT_MINIMAL 3149 Arch init code should be built for a very small image 3150 3151 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3152 Partition on the MMC to load U-Boot from when the MMC is being 3153 used in raw mode 3154 3155 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3156 Sector to load kernel uImage from when MMC is being 3157 used in raw mode (for Falcon mode) 3158 3159 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3160 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3161 Sector and number of sectors to load kernel argument 3162 parameters from when MMC is being used in raw mode 3163 (for falcon mode) 3164 3165 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3166 Partition on the MMC to load U-Boot from when the MMC is being 3167 used in fs mode 3168 3169 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3170 Filename to read to load U-Boot when reading from filesystem 3171 3172 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3173 Filename to read to load kernel uImage when reading 3174 from filesystem (for Falcon mode) 3175 3176 CONFIG_SPL_FS_LOAD_ARGS_NAME 3177 Filename to read to load kernel argument parameters 3178 when reading from filesystem (for Falcon mode) 3179 3180 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3181 Set this for NAND SPL on PPC mpc83xx targets, so that 3182 start.S waits for the rest of the SPL to load before 3183 continuing (the hardware starts execution after just 3184 loading the first page rather than the full 4K). 3185 3186 CONFIG_SPL_SKIP_RELOCATE 3187 Avoid SPL relocation 3188 3189 CONFIG_SPL_NAND_BASE 3190 Include nand_base.c in the SPL. Requires 3191 CONFIG_SPL_NAND_DRIVERS. 3192 3193 CONFIG_SPL_NAND_DRIVERS 3194 SPL uses normal NAND drivers, not minimal drivers. 3195 3196 CONFIG_SPL_NAND_ECC 3197 Include standard software ECC in the SPL 3198 3199 CONFIG_SPL_NAND_SIMPLE 3200 Support for NAND boot using simple NAND drivers that 3201 expose the cmd_ctrl() interface. 3202 3203 CONFIG_SPL_UBI 3204 Support for a lightweight UBI (fastmap) scanner and 3205 loader 3206 3207 CONFIG_SPL_NAND_RAW_ONLY 3208 Support to boot only raw u-boot.bin images. Use this only 3209 if you need to save space. 3210 3211 CONFIG_SPL_COMMON_INIT_DDR 3212 Set for common ddr init with serial presence detect in 3213 SPL binary. 3214 3215 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3216 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3217 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3218 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3219 CONFIG_SYS_NAND_ECCBYTES 3220 Defines the size and behavior of the NAND that SPL uses 3221 to read U-Boot 3222 3223 CONFIG_SPL_NAND_BOOT 3224 Add support NAND boot 3225 3226 CONFIG_SYS_NAND_U_BOOT_OFFS 3227 Location in NAND to read U-Boot from 3228 3229 CONFIG_SYS_NAND_U_BOOT_DST 3230 Location in memory to load U-Boot to 3231 3232 CONFIG_SYS_NAND_U_BOOT_SIZE 3233 Size of image to load 3234 3235 CONFIG_SYS_NAND_U_BOOT_START 3236 Entry point in loaded image to jump to 3237 3238 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3239 Define this if you need to first read the OOB and then the 3240 data. This is used, for example, on davinci platforms. 3241 3242 CONFIG_SPL_OMAP3_ID_NAND 3243 Support for an OMAP3-specific set of functions to return the 3244 ID and MFR of the first attached NAND chip, if present. 3245 3246 CONFIG_SPL_RAM_DEVICE 3247 Support for running image already present in ram, in SPL binary 3248 3249 CONFIG_SPL_PAD_TO 3250 Image offset to which the SPL should be padded before appending 3251 the SPL payload. By default, this is defined as 3252 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3253 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3254 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3255 3256 CONFIG_SPL_TARGET 3257 Final target image containing SPL and payload. Some SPLs 3258 use an arch-specific makefile fragment instead, for 3259 example if more than one image needs to be produced. 3260 3261 CONFIG_FIT_SPL_PRINT 3262 Printing information about a FIT image adds quite a bit of 3263 code to SPL. So this is normally disabled in SPL. Use this 3264 option to re-enable it. This will affect the output of the 3265 bootm command when booting a FIT image. 3266 3267- TPL framework 3268 CONFIG_TPL 3269 Enable building of TPL globally. 3270 3271 CONFIG_TPL_PAD_TO 3272 Image offset to which the TPL should be padded before appending 3273 the TPL payload. By default, this is defined as 3274 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3275 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3276 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3277 3278- Interrupt support (PPC): 3279 3280 There are common interrupt_init() and timer_interrupt() 3281 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3282 for CPU specific initialization. interrupt_init_cpu() 3283 should set decrementer_count to appropriate value. If 3284 CPU resets decrementer automatically after interrupt 3285 (ppc4xx) it should set decrementer_count to zero. 3286 timer_interrupt() calls timer_interrupt_cpu() for CPU 3287 specific handling. If board has watchdog / status_led 3288 / other_activity_monitor it works automatically from 3289 general timer_interrupt(). 3290 3291 3292Board initialization settings: 3293------------------------------ 3294 3295During Initialization u-boot calls a number of board specific functions 3296to allow the preparation of board specific prerequisites, e.g. pin setup 3297before drivers are initialized. To enable these callbacks the 3298following configuration macros have to be defined. Currently this is 3299architecture specific, so please check arch/your_architecture/lib/board.c 3300typically in board_init_f() and board_init_r(). 3301 3302- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3303- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3304- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3305- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3306 3307Configuration Settings: 3308----------------------- 3309 3310- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3311 Optionally it can be defined to support 64-bit memory commands. 3312 3313- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3314 undefine this when you're short of memory. 3315 3316- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3317 width of the commands listed in the 'help' command output. 3318 3319- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3320 prompt for user input. 3321 3322- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3323 3324- CONFIG_SYS_PBSIZE: Buffer size for Console output 3325 3326- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3327 3328- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3329 the application (usually a Linux kernel) when it is 3330 booted 3331 3332- CONFIG_SYS_BAUDRATE_TABLE: 3333 List of legal baudrate settings for this board. 3334 3335- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3336 Begin and End addresses of the area used by the 3337 simple memory test. 3338 3339- CONFIG_SYS_ALT_MEMTEST: 3340 Enable an alternate, more extensive memory test. 3341 3342- CONFIG_SYS_MEMTEST_SCRATCH: 3343 Scratch address used by the alternate memory test 3344 You only need to set this if address zero isn't writeable 3345 3346- CONFIG_SYS_MEM_RESERVE_SECURE 3347 Only implemented for ARMv8 for now. 3348 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3349 is substracted from total RAM and won't be reported to OS. 3350 This memory can be used as secure memory. A variable 3351 gd->arch.secure_ram is used to track the location. In systems 3352 the RAM base is not zero, or RAM is divided into banks, 3353 this variable needs to be recalcuated to get the address. 3354 3355- CONFIG_SYS_MEM_TOP_HIDE: 3356 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3357 this specified memory area will get subtracted from the top 3358 (end) of RAM and won't get "touched" at all by U-Boot. By 3359 fixing up gd->ram_size the Linux kernel should gets passed 3360 the now "corrected" memory size and won't touch it either. 3361 This should work for arch/ppc and arch/powerpc. Only Linux 3362 board ports in arch/powerpc with bootwrapper support that 3363 recalculate the memory size from the SDRAM controller setup 3364 will have to get fixed in Linux additionally. 3365 3366 This option can be used as a workaround for the 440EPx/GRx 3367 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3368 be touched. 3369 3370 WARNING: Please make sure that this value is a multiple of 3371 the Linux page size (normally 4k). If this is not the case, 3372 then the end address of the Linux memory will be located at a 3373 non page size aligned address and this could cause major 3374 problems. 3375 3376- CONFIG_SYS_LOADS_BAUD_CHANGE: 3377 Enable temporary baudrate change while serial download 3378 3379- CONFIG_SYS_SDRAM_BASE: 3380 Physical start address of SDRAM. _Must_ be 0 here. 3381 3382- CONFIG_SYS_FLASH_BASE: 3383 Physical start address of Flash memory. 3384 3385- CONFIG_SYS_MONITOR_BASE: 3386 Physical start address of boot monitor code (set by 3387 make config files to be same as the text base address 3388 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3389 CONFIG_SYS_FLASH_BASE when booting from flash. 3390 3391- CONFIG_SYS_MONITOR_LEN: 3392 Size of memory reserved for monitor code, used to 3393 determine _at_compile_time_ (!) if the environment is 3394 embedded within the U-Boot image, or in a separate 3395 flash sector. 3396 3397- CONFIG_SYS_MALLOC_LEN: 3398 Size of DRAM reserved for malloc() use. 3399 3400- CONFIG_SYS_MALLOC_F_LEN 3401 Size of the malloc() pool for use before relocation. If 3402 this is defined, then a very simple malloc() implementation 3403 will become available before relocation. The address is just 3404 below the global data, and the stack is moved down to make 3405 space. 3406 3407 This feature allocates regions with increasing addresses 3408 within the region. calloc() is supported, but realloc() 3409 is not available. free() is supported but does nothing. 3410 The memory will be freed (or in fact just forgotten) when 3411 U-Boot relocates itself. 3412 3413- CONFIG_SYS_MALLOC_SIMPLE 3414 Provides a simple and small malloc() and calloc() for those 3415 boards which do not use the full malloc in SPL (which is 3416 enabled with CONFIG_SYS_SPL_MALLOC_START). 3417 3418- CONFIG_SYS_NONCACHED_MEMORY: 3419 Size of non-cached memory area. This area of memory will be 3420 typically located right below the malloc() area and mapped 3421 uncached in the MMU. This is useful for drivers that would 3422 otherwise require a lot of explicit cache maintenance. For 3423 some drivers it's also impossible to properly maintain the 3424 cache. For example if the regions that need to be flushed 3425 are not a multiple of the cache-line size, *and* padding 3426 cannot be allocated between the regions to align them (i.e. 3427 if the HW requires a contiguous array of regions, and the 3428 size of each region is not cache-aligned), then a flush of 3429 one region may result in overwriting data that hardware has 3430 written to another region in the same cache-line. This can 3431 happen for example in network drivers where descriptors for 3432 buffers are typically smaller than the CPU cache-line (e.g. 3433 16 bytes vs. 32 or 64 bytes). 3434 3435 Non-cached memory is only supported on 32-bit ARM at present. 3436 3437- CONFIG_SYS_BOOTM_LEN: 3438 Normally compressed uImages are limited to an 3439 uncompressed size of 8 MBytes. If this is not enough, 3440 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3441 to adjust this setting to your needs. 3442 3443- CONFIG_SYS_BOOTMAPSZ: 3444 Maximum size of memory mapped by the startup code of 3445 the Linux kernel; all data that must be processed by 3446 the Linux kernel (bd_info, boot arguments, FDT blob if 3447 used) must be put below this limit, unless "bootm_low" 3448 environment variable is defined and non-zero. In such case 3449 all data for the Linux kernel must be between "bootm_low" 3450 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3451 variable "bootm_mapsize" will override the value of 3452 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3453 then the value in "bootm_size" will be used instead. 3454 3455- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3456 Enable initrd_high functionality. If defined then the 3457 initrd_high feature is enabled and the bootm ramdisk subcommand 3458 is enabled. 3459 3460- CONFIG_SYS_BOOT_GET_CMDLINE: 3461 Enables allocating and saving kernel cmdline in space between 3462 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3463 3464- CONFIG_SYS_BOOT_GET_KBD: 3465 Enables allocating and saving a kernel copy of the bd_info in 3466 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3467 3468- CONFIG_SYS_MAX_FLASH_BANKS: 3469 Max number of Flash memory banks 3470 3471- CONFIG_SYS_MAX_FLASH_SECT: 3472 Max number of sectors on a Flash chip 3473 3474- CONFIG_SYS_FLASH_ERASE_TOUT: 3475 Timeout for Flash erase operations (in ms) 3476 3477- CONFIG_SYS_FLASH_WRITE_TOUT: 3478 Timeout for Flash write operations (in ms) 3479 3480- CONFIG_SYS_FLASH_LOCK_TOUT 3481 Timeout for Flash set sector lock bit operation (in ms) 3482 3483- CONFIG_SYS_FLASH_UNLOCK_TOUT 3484 Timeout for Flash clear lock bits operation (in ms) 3485 3486- CONFIG_SYS_FLASH_PROTECTION 3487 If defined, hardware flash sectors protection is used 3488 instead of U-Boot software protection. 3489 3490- CONFIG_SYS_DIRECT_FLASH_TFTP: 3491 3492 Enable TFTP transfers directly to flash memory; 3493 without this option such a download has to be 3494 performed in two steps: (1) download to RAM, and (2) 3495 copy from RAM to flash. 3496 3497 The two-step approach is usually more reliable, since 3498 you can check if the download worked before you erase 3499 the flash, but in some situations (when system RAM is 3500 too limited to allow for a temporary copy of the 3501 downloaded image) this option may be very useful. 3502 3503- CONFIG_SYS_FLASH_CFI: 3504 Define if the flash driver uses extra elements in the 3505 common flash structure for storing flash geometry. 3506 3507- CONFIG_FLASH_CFI_DRIVER 3508 This option also enables the building of the cfi_flash driver 3509 in the drivers directory 3510 3511- CONFIG_FLASH_CFI_MTD 3512 This option enables the building of the cfi_mtd driver 3513 in the drivers directory. The driver exports CFI flash 3514 to the MTD layer. 3515 3516- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3517 Use buffered writes to flash. 3518 3519- CONFIG_FLASH_SPANSION_S29WS_N 3520 s29ws-n MirrorBit flash has non-standard addresses for buffered 3521 write commands. 3522 3523- CONFIG_SYS_FLASH_QUIET_TEST 3524 If this option is defined, the common CFI flash doesn't 3525 print it's warning upon not recognized FLASH banks. This 3526 is useful, if some of the configured banks are only 3527 optionally available. 3528 3529- CONFIG_FLASH_SHOW_PROGRESS 3530 If defined (must be an integer), print out countdown 3531 digits and dots. Recommended value: 45 (9..1) for 80 3532 column displays, 15 (3..1) for 40 column displays. 3533 3534- CONFIG_FLASH_VERIFY 3535 If defined, the content of the flash (destination) is compared 3536 against the source after the write operation. An error message 3537 will be printed when the contents are not identical. 3538 Please note that this option is useless in nearly all cases, 3539 since such flash programming errors usually are detected earlier 3540 while unprotecting/erasing/programming. Please only enable 3541 this option if you really know what you are doing. 3542 3543- CONFIG_SYS_RX_ETH_BUFFER: 3544 Defines the number of Ethernet receive buffers. On some 3545 Ethernet controllers it is recommended to set this value 3546 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3547 buffers can be full shortly after enabling the interface 3548 on high Ethernet traffic. 3549 Defaults to 4 if not defined. 3550 3551- CONFIG_ENV_MAX_ENTRIES 3552 3553 Maximum number of entries in the hash table that is used 3554 internally to store the environment settings. The default 3555 setting is supposed to be generous and should work in most 3556 cases. This setting can be used to tune behaviour; see 3557 lib/hashtable.c for details. 3558 3559- CONFIG_ENV_FLAGS_LIST_DEFAULT 3560- CONFIG_ENV_FLAGS_LIST_STATIC 3561 Enable validation of the values given to environment variables when 3562 calling env set. Variables can be restricted to only decimal, 3563 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3564 the variables can also be restricted to IP address or MAC address. 3565 3566 The format of the list is: 3567 type_attribute = [s|d|x|b|i|m] 3568 access_attribute = [a|r|o|c] 3569 attributes = type_attribute[access_attribute] 3570 entry = variable_name[:attributes] 3571 list = entry[,list] 3572 3573 The type attributes are: 3574 s - String (default) 3575 d - Decimal 3576 x - Hexadecimal 3577 b - Boolean ([1yYtT|0nNfF]) 3578 i - IP address 3579 m - MAC address 3580 3581 The access attributes are: 3582 a - Any (default) 3583 r - Read-only 3584 o - Write-once 3585 c - Change-default 3586 3587 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3588 Define this to a list (string) to define the ".flags" 3589 environment variable in the default or embedded environment. 3590 3591 - CONFIG_ENV_FLAGS_LIST_STATIC 3592 Define this to a list (string) to define validation that 3593 should be done if an entry is not found in the ".flags" 3594 environment variable. To override a setting in the static 3595 list, simply add an entry for the same variable name to the 3596 ".flags" variable. 3597 3598 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3599 regular expression. This allows multiple variables to define the same 3600 flags without explicitly listing them for each variable. 3601 3602- CONFIG_ENV_ACCESS_IGNORE_FORCE 3603 If defined, don't allow the -f switch to env set override variable 3604 access flags. 3605 3606- CONFIG_USE_STDINT 3607 If stdint.h is available with your toolchain you can define this 3608 option to enable it. You can provide option 'USE_STDINT=1' when 3609 building U-Boot to enable this. 3610 3611The following definitions that deal with the placement and management 3612of environment data (variable area); in general, we support the 3613following configurations: 3614 3615- CONFIG_BUILD_ENVCRC: 3616 3617 Builds up envcrc with the target environment so that external utils 3618 may easily extract it and embed it in final U-Boot images. 3619 3620- CONFIG_ENV_IS_IN_FLASH: 3621 3622 Define this if the environment is in flash memory. 3623 3624 a) The environment occupies one whole flash sector, which is 3625 "embedded" in the text segment with the U-Boot code. This 3626 happens usually with "bottom boot sector" or "top boot 3627 sector" type flash chips, which have several smaller 3628 sectors at the start or the end. For instance, such a 3629 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3630 such a case you would place the environment in one of the 3631 4 kB sectors - with U-Boot code before and after it. With 3632 "top boot sector" type flash chips, you would put the 3633 environment in one of the last sectors, leaving a gap 3634 between U-Boot and the environment. 3635 3636 - CONFIG_ENV_OFFSET: 3637 3638 Offset of environment data (variable area) to the 3639 beginning of flash memory; for instance, with bottom boot 3640 type flash chips the second sector can be used: the offset 3641 for this sector is given here. 3642 3643 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3644 3645 - CONFIG_ENV_ADDR: 3646 3647 This is just another way to specify the start address of 3648 the flash sector containing the environment (instead of 3649 CONFIG_ENV_OFFSET). 3650 3651 - CONFIG_ENV_SECT_SIZE: 3652 3653 Size of the sector containing the environment. 3654 3655 3656 b) Sometimes flash chips have few, equal sized, BIG sectors. 3657 In such a case you don't want to spend a whole sector for 3658 the environment. 3659 3660 - CONFIG_ENV_SIZE: 3661 3662 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3663 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3664 of this flash sector for the environment. This saves 3665 memory for the RAM copy of the environment. 3666 3667 It may also save flash memory if you decide to use this 3668 when your environment is "embedded" within U-Boot code, 3669 since then the remainder of the flash sector could be used 3670 for U-Boot code. It should be pointed out that this is 3671 STRONGLY DISCOURAGED from a robustness point of view: 3672 updating the environment in flash makes it always 3673 necessary to erase the WHOLE sector. If something goes 3674 wrong before the contents has been restored from a copy in 3675 RAM, your target system will be dead. 3676 3677 - CONFIG_ENV_ADDR_REDUND 3678 CONFIG_ENV_SIZE_REDUND 3679 3680 These settings describe a second storage area used to hold 3681 a redundant copy of the environment data, so that there is 3682 a valid backup copy in case there is a power failure during 3683 a "saveenv" operation. 3684 3685BE CAREFUL! Any changes to the flash layout, and some changes to the 3686source code will make it necessary to adapt <board>/u-boot.lds* 3687accordingly! 3688 3689 3690- CONFIG_ENV_IS_IN_NVRAM: 3691 3692 Define this if you have some non-volatile memory device 3693 (NVRAM, battery buffered SRAM) which you want to use for the 3694 environment. 3695 3696 - CONFIG_ENV_ADDR: 3697 - CONFIG_ENV_SIZE: 3698 3699 These two #defines are used to determine the memory area you 3700 want to use for environment. It is assumed that this memory 3701 can just be read and written to, without any special 3702 provision. 3703 3704BE CAREFUL! The first access to the environment happens quite early 3705in U-Boot initialization (when we try to get the setting of for the 3706console baudrate). You *MUST* have mapped your NVRAM area then, or 3707U-Boot will hang. 3708 3709Please note that even with NVRAM we still use a copy of the 3710environment in RAM: we could work on NVRAM directly, but we want to 3711keep settings there always unmodified except somebody uses "saveenv" 3712to save the current settings. 3713 3714 3715- CONFIG_ENV_IS_IN_EEPROM: 3716 3717 Use this if you have an EEPROM or similar serial access 3718 device and a driver for it. 3719 3720 - CONFIG_ENV_OFFSET: 3721 - CONFIG_ENV_SIZE: 3722 3723 These two #defines specify the offset and size of the 3724 environment area within the total memory of your EEPROM. 3725 3726 - CONFIG_SYS_I2C_EEPROM_ADDR: 3727 If defined, specified the chip address of the EEPROM device. 3728 The default address is zero. 3729 3730 - CONFIG_SYS_I2C_EEPROM_BUS: 3731 If defined, specified the i2c bus of the EEPROM device. 3732 3733 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3734 If defined, the number of bits used to address bytes in a 3735 single page in the EEPROM device. A 64 byte page, for example 3736 would require six bits. 3737 3738 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3739 If defined, the number of milliseconds to delay between 3740 page writes. The default is zero milliseconds. 3741 3742 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3743 The length in bytes of the EEPROM memory array address. Note 3744 that this is NOT the chip address length! 3745 3746 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3747 EEPROM chips that implement "address overflow" are ones 3748 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3749 address and the extra bits end up in the "chip address" bit 3750 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3751 byte chips. 3752 3753 Note that we consider the length of the address field to 3754 still be one byte because the extra address bits are hidden 3755 in the chip address. 3756 3757 - CONFIG_SYS_EEPROM_SIZE: 3758 The size in bytes of the EEPROM device. 3759 3760 - CONFIG_ENV_EEPROM_IS_ON_I2C 3761 define this, if you have I2C and SPI activated, and your 3762 EEPROM, which holds the environment, is on the I2C bus. 3763 3764 - CONFIG_I2C_ENV_EEPROM_BUS 3765 if you have an Environment on an EEPROM reached over 3766 I2C muxes, you can define here, how to reach this 3767 EEPROM. For example: 3768 3769 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3770 3771 EEPROM which holds the environment, is reached over 3772 a pca9547 i2c mux with address 0x70, channel 3. 3773 3774- CONFIG_ENV_IS_IN_DATAFLASH: 3775 3776 Define this if you have a DataFlash memory device which you 3777 want to use for the environment. 3778 3779 - CONFIG_ENV_OFFSET: 3780 - CONFIG_ENV_ADDR: 3781 - CONFIG_ENV_SIZE: 3782 3783 These three #defines specify the offset and size of the 3784 environment area within the total memory of your DataFlash placed 3785 at the specified address. 3786 3787- CONFIG_ENV_IS_IN_SPI_FLASH: 3788 3789 Define this if you have a SPI Flash memory device which you 3790 want to use for the environment. 3791 3792 - CONFIG_ENV_OFFSET: 3793 - CONFIG_ENV_SIZE: 3794 3795 These two #defines specify the offset and size of the 3796 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3797 aligned to an erase sector boundary. 3798 3799 - CONFIG_ENV_SECT_SIZE: 3800 3801 Define the SPI flash's sector size. 3802 3803 - CONFIG_ENV_OFFSET_REDUND (optional): 3804 3805 This setting describes a second storage area of CONFIG_ENV_SIZE 3806 size used to hold a redundant copy of the environment data, so 3807 that there is a valid backup copy in case there is a power failure 3808 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3809 aligned to an erase sector boundary. 3810 3811 - CONFIG_ENV_SPI_BUS (optional): 3812 - CONFIG_ENV_SPI_CS (optional): 3813 3814 Define the SPI bus and chip select. If not defined they will be 0. 3815 3816 - CONFIG_ENV_SPI_MAX_HZ (optional): 3817 3818 Define the SPI max work clock. If not defined then use 1MHz. 3819 3820 - CONFIG_ENV_SPI_MODE (optional): 3821 3822 Define the SPI work mode. If not defined then use SPI_MODE_3. 3823 3824- CONFIG_ENV_IS_IN_REMOTE: 3825 3826 Define this if you have a remote memory space which you 3827 want to use for the local device's environment. 3828 3829 - CONFIG_ENV_ADDR: 3830 - CONFIG_ENV_SIZE: 3831 3832 These two #defines specify the address and size of the 3833 environment area within the remote memory space. The 3834 local device can get the environment from remote memory 3835 space by SRIO or PCIE links. 3836 3837BE CAREFUL! For some special cases, the local device can not use 3838"saveenv" command. For example, the local device will get the 3839environment stored in a remote NOR flash by SRIO or PCIE link, 3840but it can not erase, write this NOR flash by SRIO or PCIE interface. 3841 3842- CONFIG_ENV_IS_IN_NAND: 3843 3844 Define this if you have a NAND device which you want to use 3845 for the environment. 3846 3847 - CONFIG_ENV_OFFSET: 3848 - CONFIG_ENV_SIZE: 3849 3850 These two #defines specify the offset and size of the environment 3851 area within the first NAND device. CONFIG_ENV_OFFSET must be 3852 aligned to an erase block boundary. 3853 3854 - CONFIG_ENV_OFFSET_REDUND (optional): 3855 3856 This setting describes a second storage area of CONFIG_ENV_SIZE 3857 size used to hold a redundant copy of the environment data, so 3858 that there is a valid backup copy in case there is a power failure 3859 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3860 aligned to an erase block boundary. 3861 3862 - CONFIG_ENV_RANGE (optional): 3863 3864 Specifies the length of the region in which the environment 3865 can be written. This should be a multiple of the NAND device's 3866 block size. Specifying a range with more erase blocks than 3867 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3868 the range to be avoided. 3869 3870 - CONFIG_ENV_OFFSET_OOB (optional): 3871 3872 Enables support for dynamically retrieving the offset of the 3873 environment from block zero's out-of-band data. The 3874 "nand env.oob" command can be used to record this offset. 3875 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3876 using CONFIG_ENV_OFFSET_OOB. 3877 3878- CONFIG_NAND_ENV_DST 3879 3880 Defines address in RAM to which the nand_spl code should copy the 3881 environment. If redundant environment is used, it will be copied to 3882 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3883 3884- CONFIG_ENV_IS_IN_UBI: 3885 3886 Define this if you have an UBI volume that you want to use for the 3887 environment. This has the benefit of wear-leveling the environment 3888 accesses, which is important on NAND. 3889 3890 - CONFIG_ENV_UBI_PART: 3891 3892 Define this to a string that is the mtd partition containing the UBI. 3893 3894 - CONFIG_ENV_UBI_VOLUME: 3895 3896 Define this to the name of the volume that you want to store the 3897 environment in. 3898 3899 - CONFIG_ENV_UBI_VOLUME_REDUND: 3900 3901 Define this to the name of another volume to store a second copy of 3902 the environment in. This will enable redundant environments in UBI. 3903 It is assumed that both volumes are in the same MTD partition. 3904 3905 - CONFIG_UBI_SILENCE_MSG 3906 - CONFIG_UBIFS_SILENCE_MSG 3907 3908 You will probably want to define these to avoid a really noisy system 3909 when storing the env in UBI. 3910 3911- CONFIG_ENV_IS_IN_FAT: 3912 Define this if you want to use the FAT file system for the environment. 3913 3914 - FAT_ENV_INTERFACE: 3915 3916 Define this to a string that is the name of the block device. 3917 3918 - FAT_ENV_DEVICE_AND_PART: 3919 3920 Define this to a string to specify the partition of the device. It can 3921 be as following: 3922 3923 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 3924 - "D:P": device D partition P. Error occurs if device D has no 3925 partition table. 3926 - "D:0": device D. 3927 - "D" or "D:": device D partition 1 if device D has partition 3928 table, or the whole device D if has no partition 3929 table. 3930 - "D:auto": first partition in device D with bootable flag set. 3931 If none, first valid partition in device D. If no 3932 partition table then means device D. 3933 3934 - FAT_ENV_FILE: 3935 3936 It's a string of the FAT file name. This file use to store the 3937 environment. 3938 3939 - CONFIG_FAT_WRITE: 3940 This should be defined. Otherwise it cannot save the environment file. 3941 3942- CONFIG_ENV_IS_IN_MMC: 3943 3944 Define this if you have an MMC device which you want to use for the 3945 environment. 3946 3947 - CONFIG_SYS_MMC_ENV_DEV: 3948 3949 Specifies which MMC device the environment is stored in. 3950 3951 - CONFIG_SYS_MMC_ENV_PART (optional): 3952 3953 Specifies which MMC partition the environment is stored in. If not 3954 set, defaults to partition 0, the user area. Common values might be 3955 1 (first MMC boot partition), 2 (second MMC boot partition). 3956 3957 - CONFIG_ENV_OFFSET: 3958 - CONFIG_ENV_SIZE: 3959 3960 These two #defines specify the offset and size of the environment 3961 area within the specified MMC device. 3962 3963 If offset is positive (the usual case), it is treated as relative to 3964 the start of the MMC partition. If offset is negative, it is treated 3965 as relative to the end of the MMC partition. This can be useful if 3966 your board may be fitted with different MMC devices, which have 3967 different sizes for the MMC partitions, and you always want the 3968 environment placed at the very end of the partition, to leave the 3969 maximum possible space before it, to store other data. 3970 3971 These two values are in units of bytes, but must be aligned to an 3972 MMC sector boundary. 3973 3974 - CONFIG_ENV_OFFSET_REDUND (optional): 3975 3976 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 3977 hold a redundant copy of the environment data. This provides a 3978 valid backup copy in case the other copy is corrupted, e.g. due 3979 to a power failure during a "saveenv" operation. 3980 3981 This value may also be positive or negative; this is handled in the 3982 same way as CONFIG_ENV_OFFSET. 3983 3984 This value is also in units of bytes, but must also be aligned to 3985 an MMC sector boundary. 3986 3987 - CONFIG_ENV_SIZE_REDUND (optional): 3988 3989 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 3990 set. If this value is set, it must be set to the same value as 3991 CONFIG_ENV_SIZE. 3992 3993- CONFIG_SYS_SPI_INIT_OFFSET 3994 3995 Defines offset to the initial SPI buffer area in DPRAM. The 3996 area is used at an early stage (ROM part) if the environment 3997 is configured to reside in the SPI EEPROM: We need a 520 byte 3998 scratch DPRAM area. It is used between the two initialization 3999 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4000 to be a good choice since it makes it far enough from the 4001 start of the data area as well as from the stack pointer. 4002 4003Please note that the environment is read-only until the monitor 4004has been relocated to RAM and a RAM copy of the environment has been 4005created; also, when using EEPROM you will have to use getenv_f() 4006until then to read environment variables. 4007 4008The environment is protected by a CRC32 checksum. Before the monitor 4009is relocated into RAM, as a result of a bad CRC you will be working 4010with the compiled-in default environment - *silently*!!! [This is 4011necessary, because the first environment variable we need is the 4012"baudrate" setting for the console - if we have a bad CRC, we don't 4013have any device yet where we could complain.] 4014 4015Note: once the monitor has been relocated, then it will complain if 4016the default environment is used; a new CRC is computed as soon as you 4017use the "saveenv" command to store a valid environment. 4018 4019- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4020 Echo the inverted Ethernet link state to the fault LED. 4021 4022 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4023 also needs to be defined. 4024 4025- CONFIG_SYS_FAULT_MII_ADDR: 4026 MII address of the PHY to check for the Ethernet link state. 4027 4028- CONFIG_NS16550_MIN_FUNCTIONS: 4029 Define this if you desire to only have use of the NS16550_init 4030 and NS16550_putc functions for the serial driver located at 4031 drivers/serial/ns16550.c. This option is useful for saving 4032 space for already greatly restricted images, including but not 4033 limited to NAND_SPL configurations. 4034 4035- CONFIG_DISPLAY_BOARDINFO 4036 Display information about the board that U-Boot is running on 4037 when U-Boot starts up. The board function checkboard() is called 4038 to do this. 4039 4040- CONFIG_DISPLAY_BOARDINFO_LATE 4041 Similar to the previous option, but display this information 4042 later, once stdio is running and output goes to the LCD, if 4043 present. 4044 4045- CONFIG_BOARD_SIZE_LIMIT: 4046 Maximum size of the U-Boot image. When defined, the 4047 build system checks that the actual size does not 4048 exceed it. 4049 4050Low Level (hardware related) configuration options: 4051--------------------------------------------------- 4052 4053- CONFIG_SYS_CACHELINE_SIZE: 4054 Cache Line Size of the CPU. 4055 4056- CONFIG_SYS_DEFAULT_IMMR: 4057 Default address of the IMMR after system reset. 4058 4059 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4060 and RPXsuper) to be able to adjust the position of 4061 the IMMR register after a reset. 4062 4063- CONFIG_SYS_CCSRBAR_DEFAULT: 4064 Default (power-on reset) physical address of CCSR on Freescale 4065 PowerPC SOCs. 4066 4067- CONFIG_SYS_CCSRBAR: 4068 Virtual address of CCSR. On a 32-bit build, this is typically 4069 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4070 4071 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4072 for cross-platform code that uses that macro instead. 4073 4074- CONFIG_SYS_CCSRBAR_PHYS: 4075 Physical address of CCSR. CCSR can be relocated to a new 4076 physical address, if desired. In this case, this macro should 4077 be set to that address. Otherwise, it should be set to the 4078 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4079 is typically relocated on 36-bit builds. It is recommended 4080 that this macro be defined via the _HIGH and _LOW macros: 4081 4082 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4083 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4084 4085- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4086 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4087 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4088 used in assembly code, so it must not contain typecasts or 4089 integer size suffixes (e.g. "ULL"). 4090 4091- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4092 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4093 used in assembly code, so it must not contain typecasts or 4094 integer size suffixes (e.g. "ULL"). 4095 4096- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4097 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4098 forced to a value that ensures that CCSR is not relocated. 4099 4100- Floppy Disk Support: 4101 CONFIG_SYS_FDC_DRIVE_NUMBER 4102 4103 the default drive number (default value 0) 4104 4105 CONFIG_SYS_ISA_IO_STRIDE 4106 4107 defines the spacing between FDC chipset registers 4108 (default value 1) 4109 4110 CONFIG_SYS_ISA_IO_OFFSET 4111 4112 defines the offset of register from address. It 4113 depends on which part of the data bus is connected to 4114 the FDC chipset. (default value 0) 4115 4116 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4117 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4118 default value. 4119 4120 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4121 fdc_hw_init() is called at the beginning of the FDC 4122 setup. fdc_hw_init() must be provided by the board 4123 source code. It is used to make hardware-dependent 4124 initializations. 4125 4126- CONFIG_IDE_AHB: 4127 Most IDE controllers were designed to be connected with PCI 4128 interface. Only few of them were designed for AHB interface. 4129 When software is doing ATA command and data transfer to 4130 IDE devices through IDE-AHB controller, some additional 4131 registers accessing to these kind of IDE-AHB controller 4132 is required. 4133 4134- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4135 DO NOT CHANGE unless you know exactly what you're 4136 doing! (11-4) [MPC8xx/82xx systems only] 4137 4138- CONFIG_SYS_INIT_RAM_ADDR: 4139 4140 Start address of memory area that can be used for 4141 initial data and stack; please note that this must be 4142 writable memory that is working WITHOUT special 4143 initialization, i. e. you CANNOT use normal RAM which 4144 will become available only after programming the 4145 memory controller and running certain initialization 4146 sequences. 4147 4148 U-Boot uses the following memory types: 4149 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4150 - MPC824X: data cache 4151 - PPC4xx: data cache 4152 4153- CONFIG_SYS_GBL_DATA_OFFSET: 4154 4155 Offset of the initial data structure in the memory 4156 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4157 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4158 data is located at the end of the available space 4159 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4160 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4161 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4162 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4163 4164 Note: 4165 On the MPC824X (or other systems that use the data 4166 cache for initial memory) the address chosen for 4167 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4168 point to an otherwise UNUSED address space between 4169 the top of RAM and the start of the PCI space. 4170 4171- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4172 4173- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4174 4175- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4176 4177- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4178 4179- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4180 4181- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4182 4183- CONFIG_SYS_OR_TIMING_SDRAM: 4184 SDRAM timing 4185 4186- CONFIG_SYS_MAMR_PTA: 4187 periodic timer for refresh 4188 4189- CONFIG_SYS_DER: Debug Event Register (37-47) 4190 4191- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4192 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4193 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4194 CONFIG_SYS_BR1_PRELIM: 4195 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4196 4197- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4198 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4199 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4200 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4201 4202- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4203 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4204 Machine Mode Register and Memory Periodic Timer 4205 Prescaler definitions (SDRAM timing) 4206 4207- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4208 enable I2C microcode relocation patch (MPC8xx); 4209 define relocation offset in DPRAM [DSP2] 4210 4211- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4212 enable SMC microcode relocation patch (MPC8xx); 4213 define relocation offset in DPRAM [SMC1] 4214 4215- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4216 enable SPI microcode relocation patch (MPC8xx); 4217 define relocation offset in DPRAM [SCC4] 4218 4219- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4220 Offset of the bootmode word in DPRAM used by post 4221 (Power On Self Tests). This definition overrides 4222 #define'd default value in commproc.h resp. 4223 cpm_8260.h. 4224 4225- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4226 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4227 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4228 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4229 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4230 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4231 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4232 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4233 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4234 4235- CONFIG_PCI_DISABLE_PCIE: 4236 Disable PCI-Express on systems where it is supported but not 4237 required. 4238 4239- CONFIG_PCI_ENUM_ONLY 4240 Only scan through and get the devices on the buses. 4241 Don't do any setup work, presumably because someone or 4242 something has already done it, and we don't need to do it 4243 a second time. Useful for platforms that are pre-booted 4244 by coreboot or similar. 4245 4246- CONFIG_PCI_INDIRECT_BRIDGE: 4247 Enable support for indirect PCI bridges. 4248 4249- CONFIG_SYS_SRIO: 4250 Chip has SRIO or not 4251 4252- CONFIG_SRIO1: 4253 Board has SRIO 1 port available 4254 4255- CONFIG_SRIO2: 4256 Board has SRIO 2 port available 4257 4258- CONFIG_SRIO_PCIE_BOOT_MASTER 4259 Board can support master function for Boot from SRIO and PCIE 4260 4261- CONFIG_SYS_SRIOn_MEM_VIRT: 4262 Virtual Address of SRIO port 'n' memory region 4263 4264- CONFIG_SYS_SRIOn_MEM_PHYS: 4265 Physical Address of SRIO port 'n' memory region 4266 4267- CONFIG_SYS_SRIOn_MEM_SIZE: 4268 Size of SRIO port 'n' memory region 4269 4270- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4271 Defined to tell the NAND controller that the NAND chip is using 4272 a 16 bit bus. 4273 Not all NAND drivers use this symbol. 4274 Example of drivers that use it: 4275 - drivers/mtd/nand/ndfc.c 4276 - drivers/mtd/nand/mxc_nand.c 4277 4278- CONFIG_SYS_NDFC_EBC0_CFG 4279 Sets the EBC0_CFG register for the NDFC. If not defined 4280 a default value will be used. 4281 4282- CONFIG_SPD_EEPROM 4283 Get DDR timing information from an I2C EEPROM. Common 4284 with pluggable memory modules such as SODIMMs 4285 4286 SPD_EEPROM_ADDRESS 4287 I2C address of the SPD EEPROM 4288 4289- CONFIG_SYS_SPD_BUS_NUM 4290 If SPD EEPROM is on an I2C bus other than the first 4291 one, specify here. Note that the value must resolve 4292 to something your driver can deal with. 4293 4294- CONFIG_SYS_DDR_RAW_TIMING 4295 Get DDR timing information from other than SPD. Common with 4296 soldered DDR chips onboard without SPD. DDR raw timing 4297 parameters are extracted from datasheet and hard-coded into 4298 header files or board specific files. 4299 4300- CONFIG_FSL_DDR_INTERACTIVE 4301 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4302 4303- CONFIG_FSL_DDR_SYNC_REFRESH 4304 Enable sync of refresh for multiple controllers. 4305 4306- CONFIG_FSL_DDR_BIST 4307 Enable built-in memory test for Freescale DDR controllers. 4308 4309- CONFIG_SYS_83XX_DDR_USES_CS0 4310 Only for 83xx systems. If specified, then DDR should 4311 be configured using CS0 and CS1 instead of CS2 and CS3. 4312 4313- CONFIG_ETHER_ON_FEC[12] 4314 Define to enable FEC[12] on a 8xx series processor. 4315 4316- CONFIG_FEC[12]_PHY 4317 Define to the hardcoded PHY address which corresponds 4318 to the given FEC; i. e. 4319 #define CONFIG_FEC1_PHY 4 4320 means that the PHY with address 4 is connected to FEC1 4321 4322 When set to -1, means to probe for first available. 4323 4324- CONFIG_FEC[12]_PHY_NORXERR 4325 The PHY does not have a RXERR line (RMII only). 4326 (so program the FEC to ignore it). 4327 4328- CONFIG_RMII 4329 Enable RMII mode for all FECs. 4330 Note that this is a global option, we can't 4331 have one FEC in standard MII mode and another in RMII mode. 4332 4333- CONFIG_CRC32_VERIFY 4334 Add a verify option to the crc32 command. 4335 The syntax is: 4336 4337 => crc32 -v <address> <count> <crc32> 4338 4339 Where address/count indicate a memory area 4340 and crc32 is the correct crc32 which the 4341 area should have. 4342 4343- CONFIG_LOOPW 4344 Add the "loopw" memory command. This only takes effect if 4345 the memory commands are activated globally (CONFIG_CMD_MEM). 4346 4347- CONFIG_MX_CYCLIC 4348 Add the "mdc" and "mwc" memory commands. These are cyclic 4349 "md/mw" commands. 4350 Examples: 4351 4352 => mdc.b 10 4 500 4353 This command will print 4 bytes (10,11,12,13) each 500 ms. 4354 4355 => mwc.l 100 12345678 10 4356 This command will write 12345678 to address 100 all 10 ms. 4357 4358 This only takes effect if the memory commands are activated 4359 globally (CONFIG_CMD_MEM). 4360 4361- CONFIG_SKIP_LOWLEVEL_INIT 4362 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4363 low level initializations (like setting up the memory 4364 controller) are omitted and/or U-Boot does not 4365 relocate itself into RAM. 4366 4367 Normally this variable MUST NOT be defined. The only 4368 exception is when U-Boot is loaded (to RAM) by some 4369 other boot loader or by a debugger which performs 4370 these initializations itself. 4371 4372- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4373 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4374 to be skipped. The normal CP15 init (such as enabling the 4375 instruction cache) is still performed. 4376 4377- CONFIG_SPL_BUILD 4378 Modifies the behaviour of start.S when compiling a loader 4379 that is executed before the actual U-Boot. E.g. when 4380 compiling a NAND SPL. 4381 4382- CONFIG_TPL_BUILD 4383 Modifies the behaviour of start.S when compiling a loader 4384 that is executed after the SPL and before the actual U-Boot. 4385 It is loaded by the SPL. 4386 4387- CONFIG_SYS_MPC85XX_NO_RESETVEC 4388 Only for 85xx systems. If this variable is specified, the section 4389 .resetvec is not kept and the section .bootpg is placed in the 4390 previous 4k of the .text section. 4391 4392- CONFIG_ARCH_MAP_SYSMEM 4393 Generally U-Boot (and in particular the md command) uses 4394 effective address. It is therefore not necessary to regard 4395 U-Boot address as virtual addresses that need to be translated 4396 to physical addresses. However, sandbox requires this, since 4397 it maintains its own little RAM buffer which contains all 4398 addressable memory. This option causes some memory accesses 4399 to be mapped through map_sysmem() / unmap_sysmem(). 4400 4401- CONFIG_X86_RESET_VECTOR 4402 If defined, the x86 reset vector code is included. This is not 4403 needed when U-Boot is running from Coreboot. 4404 4405- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4406 Enables the RTC32K OSC on AM33xx based plattforms 4407 4408- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4409 Option to disable subpage write in NAND driver 4410 driver that uses this: 4411 drivers/mtd/nand/davinci_nand.c 4412 4413Freescale QE/FMAN Firmware Support: 4414----------------------------------- 4415 4416The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4417loading of "firmware", which is encoded in the QE firmware binary format. 4418This firmware often needs to be loaded during U-Boot booting, so macros 4419are used to identify the storage device (NOR flash, SPI, etc) and the address 4420within that device. 4421 4422- CONFIG_SYS_FMAN_FW_ADDR 4423 The address in the storage device where the FMAN microcode is located. The 4424 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4425 is also specified. 4426 4427- CONFIG_SYS_QE_FW_ADDR 4428 The address in the storage device where the QE microcode is located. The 4429 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4430 is also specified. 4431 4432- CONFIG_SYS_QE_FMAN_FW_LENGTH 4433 The maximum possible size of the firmware. The firmware binary format 4434 has a field that specifies the actual size of the firmware, but it 4435 might not be possible to read any part of the firmware unless some 4436 local storage is allocated to hold the entire firmware first. 4437 4438- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4439 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4440 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4441 virtual address in NOR flash. 4442 4443- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4444 Specifies that QE/FMAN firmware is located in NAND flash. 4445 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4446 4447- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4448 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4449 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4450 4451- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4452 Specifies that QE/FMAN firmware is located in the remote (master) 4453 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4454 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4455 window->master inbound window->master LAW->the ucode address in 4456 master's memory space. 4457 4458Freescale Layerscape Management Complex Firmware Support: 4459--------------------------------------------------------- 4460The Freescale Layerscape Management Complex (MC) supports the loading of 4461"firmware". 4462This firmware often needs to be loaded during U-Boot booting, so macros 4463are used to identify the storage device (NOR flash, SPI, etc) and the address 4464within that device. 4465 4466- CONFIG_FSL_MC_ENET 4467 Enable the MC driver for Layerscape SoCs. 4468 4469Freescale Layerscape Debug Server Support: 4470------------------------------------------- 4471The Freescale Layerscape Debug Server Support supports the loading of 4472"Debug Server firmware" and triggering SP boot-rom. 4473This firmware often needs to be loaded during U-Boot booting. 4474 4475- CONFIG_SYS_MC_RSV_MEM_ALIGN 4476 Define alignment of reserved memory MC requires 4477 4478Reproducible builds 4479------------------- 4480 4481In order to achieve reproducible builds, timestamps used in the U-Boot build 4482process have to be set to a fixed value. 4483 4484This is done using the SOURCE_DATE_EPOCH environment variable. 4485SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4486option for U-Boot or an environment variable in U-Boot. 4487 4488SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4489 4490Building the Software: 4491====================== 4492 4493Building U-Boot has been tested in several native build environments 4494and in many different cross environments. Of course we cannot support 4495all possibly existing versions of cross development tools in all 4496(potentially obsolete) versions. In case of tool chain problems we 4497recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4498which is extensively used to build and test U-Boot. 4499 4500If you are not using a native environment, it is assumed that you 4501have GNU cross compiling tools available in your path. In this case, 4502you must set the environment variable CROSS_COMPILE in your shell. 4503Note that no changes to the Makefile or any other source files are 4504necessary. For example using the ELDK on a 4xx CPU, please enter: 4505 4506 $ CROSS_COMPILE=ppc_4xx- 4507 $ export CROSS_COMPILE 4508 4509Note: If you wish to generate Windows versions of the utilities in 4510 the tools directory you can use the MinGW toolchain 4511 (http://www.mingw.org). Set your HOST tools to the MinGW 4512 toolchain and execute 'make tools'. For example: 4513 4514 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4515 4516 Binaries such as tools/mkimage.exe will be created which can 4517 be executed on computers running Windows. 4518 4519U-Boot is intended to be simple to build. After installing the 4520sources you must configure U-Boot for one specific board type. This 4521is done by typing: 4522 4523 make NAME_defconfig 4524 4525where "NAME_defconfig" is the name of one of the existing configu- 4526rations; see boards.cfg for supported names. 4527 4528Note: for some board special configuration names may exist; check if 4529 additional information is available from the board vendor; for 4530 instance, the TQM823L systems are available without (standard) 4531 or with LCD support. You can select such additional "features" 4532 when choosing the configuration, i. e. 4533 4534 make TQM823L_defconfig 4535 - will configure for a plain TQM823L, i. e. no LCD support 4536 4537 make TQM823L_LCD_defconfig 4538 - will configure for a TQM823L with U-Boot console on LCD 4539 4540 etc. 4541 4542 4543Finally, type "make all", and you should get some working U-Boot 4544images ready for download to / installation on your system: 4545 4546- "u-boot.bin" is a raw binary image 4547- "u-boot" is an image in ELF binary format 4548- "u-boot.srec" is in Motorola S-Record format 4549 4550By default the build is performed locally and the objects are saved 4551in the source directory. One of the two methods can be used to change 4552this behavior and build U-Boot to some external directory: 4553 45541. Add O= to the make command line invocations: 4555 4556 make O=/tmp/build distclean 4557 make O=/tmp/build NAME_defconfig 4558 make O=/tmp/build all 4559 45602. Set environment variable KBUILD_OUTPUT to point to the desired location: 4561 4562 export KBUILD_OUTPUT=/tmp/build 4563 make distclean 4564 make NAME_defconfig 4565 make all 4566 4567Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4568variable. 4569 4570 4571Please be aware that the Makefiles assume you are using GNU make, so 4572for instance on NetBSD you might need to use "gmake" instead of 4573native "make". 4574 4575 4576If the system board that you have is not listed, then you will need 4577to port U-Boot to your hardware platform. To do this, follow these 4578steps: 4579 45801. Create a new directory to hold your board specific code. Add any 4581 files you need. In your board directory, you will need at least 4582 the "Makefile" and a "<board>.c". 45832. Create a new configuration file "include/configs/<board>.h" for 4584 your board. 45853. If you're porting U-Boot to a new CPU, then also create a new 4586 directory to hold your CPU specific code. Add any files you need. 45874. Run "make <board>_defconfig" with your new name. 45885. Type "make", and you should get a working "u-boot.srec" file 4589 to be installed on your target system. 45906. Debug and solve any problems that might arise. 4591 [Of course, this last step is much harder than it sounds.] 4592 4593 4594Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4595============================================================== 4596 4597If you have modified U-Boot sources (for instance added a new board 4598or support for new devices, a new CPU, etc.) you are expected to 4599provide feedback to the other developers. The feedback normally takes 4600the form of a "patch", i. e. a context diff against a certain (latest 4601official or latest in the git repository) version of U-Boot sources. 4602 4603But before you submit such a patch, please verify that your modifi- 4604cation did not break existing code. At least make sure that *ALL* of 4605the supported boards compile WITHOUT ANY compiler warnings. To do so, 4606just run the buildman script (tools/buildman/buildman), which will 4607configure and build U-Boot for ALL supported system. Be warned, this 4608will take a while. Please see the buildman README, or run 'buildman -H' 4609for documentation. 4610 4611 4612See also "U-Boot Porting Guide" below. 4613 4614 4615Monitor Commands - Overview: 4616============================ 4617 4618go - start application at address 'addr' 4619run - run commands in an environment variable 4620bootm - boot application image from memory 4621bootp - boot image via network using BootP/TFTP protocol 4622bootz - boot zImage from memory 4623tftpboot- boot image via network using TFTP protocol 4624 and env variables "ipaddr" and "serverip" 4625 (and eventually "gatewayip") 4626tftpput - upload a file via network using TFTP protocol 4627rarpboot- boot image via network using RARP/TFTP protocol 4628diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4629loads - load S-Record file over serial line 4630loadb - load binary file over serial line (kermit mode) 4631md - memory display 4632mm - memory modify (auto-incrementing) 4633nm - memory modify (constant address) 4634mw - memory write (fill) 4635cp - memory copy 4636cmp - memory compare 4637crc32 - checksum calculation 4638i2c - I2C sub-system 4639sspi - SPI utility commands 4640base - print or set address offset 4641printenv- print environment variables 4642setenv - set environment variables 4643saveenv - save environment variables to persistent storage 4644protect - enable or disable FLASH write protection 4645erase - erase FLASH memory 4646flinfo - print FLASH memory information 4647nand - NAND memory operations (see doc/README.nand) 4648bdinfo - print Board Info structure 4649iminfo - print header information for application image 4650coninfo - print console devices and informations 4651ide - IDE sub-system 4652loop - infinite loop on address range 4653loopw - infinite write loop on address range 4654mtest - simple RAM test 4655icache - enable or disable instruction cache 4656dcache - enable or disable data cache 4657reset - Perform RESET of the CPU 4658echo - echo args to console 4659version - print monitor version 4660help - print online help 4661? - alias for 'help' 4662 4663 4664Monitor Commands - Detailed Description: 4665======================================== 4666 4667TODO. 4668 4669For now: just type "help <command>". 4670 4671 4672Environment Variables: 4673====================== 4674 4675U-Boot supports user configuration using Environment Variables which 4676can be made persistent by saving to Flash memory. 4677 4678Environment Variables are set using "setenv", printed using 4679"printenv", and saved to Flash using "saveenv". Using "setenv" 4680without a value can be used to delete a variable from the 4681environment. As long as you don't save the environment you are 4682working with an in-memory copy. In case the Flash area containing the 4683environment is erased by accident, a default environment is provided. 4684 4685Some configuration options can be set using Environment Variables. 4686 4687List of environment variables (most likely not complete): 4688 4689 baudrate - see CONFIG_BAUDRATE 4690 4691 bootdelay - see CONFIG_BOOTDELAY 4692 4693 bootcmd - see CONFIG_BOOTCOMMAND 4694 4695 bootargs - Boot arguments when booting an RTOS image 4696 4697 bootfile - Name of the image to load with TFTP 4698 4699 bootm_low - Memory range available for image processing in the bootm 4700 command can be restricted. This variable is given as 4701 a hexadecimal number and defines lowest address allowed 4702 for use by the bootm command. See also "bootm_size" 4703 environment variable. Address defined by "bootm_low" is 4704 also the base of the initial memory mapping for the Linux 4705 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4706 bootm_mapsize. 4707 4708 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4709 This variable is given as a hexadecimal number and it 4710 defines the size of the memory region starting at base 4711 address bootm_low that is accessible by the Linux kernel 4712 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4713 as the default value if it is defined, and bootm_size is 4714 used otherwise. 4715 4716 bootm_size - Memory range available for image processing in the bootm 4717 command can be restricted. This variable is given as 4718 a hexadecimal number and defines the size of the region 4719 allowed for use by the bootm command. See also "bootm_low" 4720 environment variable. 4721 4722 updatefile - Location of the software update file on a TFTP server, used 4723 by the automatic software update feature. Please refer to 4724 documentation in doc/README.update for more details. 4725 4726 autoload - if set to "no" (any string beginning with 'n'), 4727 "bootp" will just load perform a lookup of the 4728 configuration from the BOOTP server, but not try to 4729 load any image using TFTP 4730 4731 autostart - if set to "yes", an image loaded using the "bootp", 4732 "rarpboot", "tftpboot" or "diskboot" commands will 4733 be automatically started (by internally calling 4734 "bootm") 4735 4736 If set to "no", a standalone image passed to the 4737 "bootm" command will be copied to the load address 4738 (and eventually uncompressed), but NOT be started. 4739 This can be used to load and uncompress arbitrary 4740 data. 4741 4742 fdt_high - if set this restricts the maximum address that the 4743 flattened device tree will be copied into upon boot. 4744 For example, if you have a system with 1 GB memory 4745 at physical address 0x10000000, while Linux kernel 4746 only recognizes the first 704 MB as low memory, you 4747 may need to set fdt_high as 0x3C000000 to have the 4748 device tree blob be copied to the maximum address 4749 of the 704 MB low memory, so that Linux kernel can 4750 access it during the boot procedure. 4751 4752 If this is set to the special value 0xFFFFFFFF then 4753 the fdt will not be copied at all on boot. For this 4754 to work it must reside in writable memory, have 4755 sufficient padding on the end of it for u-boot to 4756 add the information it needs into it, and the memory 4757 must be accessible by the kernel. 4758 4759 fdtcontroladdr- if set this is the address of the control flattened 4760 device tree used by U-Boot when CONFIG_OF_CONTROL is 4761 defined. 4762 4763 i2cfast - (PPC405GP|PPC405EP only) 4764 if set to 'y' configures Linux I2C driver for fast 4765 mode (400kHZ). This environment variable is used in 4766 initialization code. So, for changes to be effective 4767 it must be saved and board must be reset. 4768 4769 initrd_high - restrict positioning of initrd images: 4770 If this variable is not set, initrd images will be 4771 copied to the highest possible address in RAM; this 4772 is usually what you want since it allows for 4773 maximum initrd size. If for some reason you want to 4774 make sure that the initrd image is loaded below the 4775 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4776 variable to a value of "no" or "off" or "0". 4777 Alternatively, you can set it to a maximum upper 4778 address to use (U-Boot will still check that it 4779 does not overwrite the U-Boot stack and data). 4780 4781 For instance, when you have a system with 16 MB 4782 RAM, and want to reserve 4 MB from use by Linux, 4783 you can do this by adding "mem=12M" to the value of 4784 the "bootargs" variable. However, now you must make 4785 sure that the initrd image is placed in the first 4786 12 MB as well - this can be done with 4787 4788 setenv initrd_high 00c00000 4789 4790 If you set initrd_high to 0xFFFFFFFF, this is an 4791 indication to U-Boot that all addresses are legal 4792 for the Linux kernel, including addresses in flash 4793 memory. In this case U-Boot will NOT COPY the 4794 ramdisk at all. This may be useful to reduce the 4795 boot time on your system, but requires that this 4796 feature is supported by your Linux kernel. 4797 4798 ipaddr - IP address; needed for tftpboot command 4799 4800 loadaddr - Default load address for commands like "bootp", 4801 "rarpboot", "tftpboot", "loadb" or "diskboot" 4802 4803 loads_echo - see CONFIG_LOADS_ECHO 4804 4805 serverip - TFTP server IP address; needed for tftpboot command 4806 4807 bootretry - see CONFIG_BOOT_RETRY_TIME 4808 4809 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4810 4811 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4812 4813 ethprime - controls which interface is used first. 4814 4815 ethact - controls which interface is currently active. 4816 For example you can do the following 4817 4818 => setenv ethact FEC 4819 => ping 192.168.0.1 # traffic sent on FEC 4820 => setenv ethact SCC 4821 => ping 10.0.0.1 # traffic sent on SCC 4822 4823 ethrotate - When set to "no" U-Boot does not go through all 4824 available network interfaces. 4825 It just stays at the currently selected interface. 4826 4827 netretry - When set to "no" each network operation will 4828 either succeed or fail without retrying. 4829 When set to "once" the network operation will 4830 fail when all the available network interfaces 4831 are tried once without success. 4832 Useful on scripts which control the retry operation 4833 themselves. 4834 4835 npe_ucode - set load address for the NPE microcode 4836 4837 silent_linux - If set then Linux will be told to boot silently, by 4838 changing the console to be empty. If "yes" it will be 4839 made silent. If "no" it will not be made silent. If 4840 unset, then it will be made silent if the U-Boot console 4841 is silent. 4842 4843 tftpsrcp - If this is set, the value is used for TFTP's 4844 UDP source port. 4845 4846 tftpdstp - If this is set, the value is used for TFTP's UDP 4847 destination port instead of the Well Know Port 69. 4848 4849 tftpblocksize - Block size to use for TFTP transfers; if not set, 4850 we use the TFTP server's default block size 4851 4852 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4853 seconds, minimum value is 1000 = 1 second). Defines 4854 when a packet is considered to be lost so it has to 4855 be retransmitted. The default is 5000 = 5 seconds. 4856 Lowering this value may make downloads succeed 4857 faster in networks with high packet loss rates or 4858 with unreliable TFTP servers. 4859 4860 tftptimeoutcountmax - maximum count of TFTP timeouts (no 4861 unit, minimum value = 0). Defines how many timeouts 4862 can happen during a single file transfer before that 4863 transfer is aborted. The default is 10, and 0 means 4864 'no timeouts allowed'. Increasing this value may help 4865 downloads succeed with high packet loss rates, or with 4866 unreliable TFTP servers or client hardware. 4867 4868 vlan - When set to a value < 4095 the traffic over 4869 Ethernet is encapsulated/received over 802.1q 4870 VLAN tagged frames. 4871 4872 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 4873 Unsigned value, in milliseconds. If not set, the period will 4874 be either the default (28000), or a value based on 4875 CONFIG_NET_RETRY_COUNT, if defined. This value has 4876 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 4877 4878The following image location variables contain the location of images 4879used in booting. The "Image" column gives the role of the image and is 4880not an environment variable name. The other columns are environment 4881variable names. "File Name" gives the name of the file on a TFTP 4882server, "RAM Address" gives the location in RAM the image will be 4883loaded to, and "Flash Location" gives the image's address in NOR 4884flash or offset in NAND flash. 4885 4886*Note* - these variables don't have to be defined for all boards, some 4887boards currently use other variables for these purposes, and some 4888boards use these variables for other purposes. 4889 4890Image File Name RAM Address Flash Location 4891----- --------- ----------- -------------- 4892u-boot u-boot u-boot_addr_r u-boot_addr 4893Linux kernel bootfile kernel_addr_r kernel_addr 4894device tree blob fdtfile fdt_addr_r fdt_addr 4895ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4896 4897The following environment variables may be used and automatically 4898updated by the network boot commands ("bootp" and "rarpboot"), 4899depending the information provided by your boot server: 4900 4901 bootfile - see above 4902 dnsip - IP address of your Domain Name Server 4903 dnsip2 - IP address of your secondary Domain Name Server 4904 gatewayip - IP address of the Gateway (Router) to use 4905 hostname - Target hostname 4906 ipaddr - see above 4907 netmask - Subnet Mask 4908 rootpath - Pathname of the root filesystem on the NFS server 4909 serverip - see above 4910 4911 4912There are two special Environment Variables: 4913 4914 serial# - contains hardware identification information such 4915 as type string and/or serial number 4916 ethaddr - Ethernet address 4917 4918These variables can be set only once (usually during manufacturing of 4919the board). U-Boot refuses to delete or overwrite these variables 4920once they have been set once. 4921 4922 4923Further special Environment Variables: 4924 4925 ver - Contains the U-Boot version string as printed 4926 with the "version" command. This variable is 4927 readonly (see CONFIG_VERSION_VARIABLE). 4928 4929 4930Please note that changes to some configuration parameters may take 4931only effect after the next boot (yes, that's just like Windoze :-). 4932 4933 4934Callback functions for environment variables: 4935--------------------------------------------- 4936 4937For some environment variables, the behavior of u-boot needs to change 4938when their values are changed. This functionality allows functions to 4939be associated with arbitrary variables. On creation, overwrite, or 4940deletion, the callback will provide the opportunity for some side 4941effect to happen or for the change to be rejected. 4942 4943The callbacks are named and associated with a function using the 4944U_BOOT_ENV_CALLBACK macro in your board or driver code. 4945 4946These callbacks are associated with variables in one of two ways. The 4947static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4948in the board configuration to a string that defines a list of 4949associations. The list must be in the following format: 4950 4951 entry = variable_name[:callback_name] 4952 list = entry[,list] 4953 4954If the callback name is not specified, then the callback is deleted. 4955Spaces are also allowed anywhere in the list. 4956 4957Callbacks can also be associated by defining the ".callbacks" variable 4958with the same list format above. Any association in ".callbacks" will 4959override any association in the static list. You can define 4960CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4961".callbacks" environment variable in the default or embedded environment. 4962 4963If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4964regular expression. This allows multiple variables to be connected to 4965the same callback without explicitly listing them all out. 4966 4967 4968Command Line Parsing: 4969===================== 4970 4971There are two different command line parsers available with U-Boot: 4972the old "simple" one, and the much more powerful "hush" shell: 4973 4974Old, simple command line parser: 4975-------------------------------- 4976 4977- supports environment variables (through setenv / saveenv commands) 4978- several commands on one line, separated by ';' 4979- variable substitution using "... ${name} ..." syntax 4980- special characters ('$', ';') can be escaped by prefixing with '\', 4981 for example: 4982 setenv bootcmd bootm \${address} 4983- You can also escape text by enclosing in single apostrophes, for example: 4984 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4985 4986Hush shell: 4987----------- 4988 4989- similar to Bourne shell, with control structures like 4990 if...then...else...fi, for...do...done; while...do...done, 4991 until...do...done, ... 4992- supports environment ("global") variables (through setenv / saveenv 4993 commands) and local shell variables (through standard shell syntax 4994 "name=value"); only environment variables can be used with "run" 4995 command 4996 4997General rules: 4998-------------- 4999 5000(1) If a command line (or an environment variable executed by a "run" 5001 command) contains several commands separated by semicolon, and 5002 one of these commands fails, then the remaining commands will be 5003 executed anyway. 5004 5005(2) If you execute several variables with one call to run (i. e. 5006 calling run with a list of variables as arguments), any failing 5007 command will cause "run" to terminate, i. e. the remaining 5008 variables are not executed. 5009 5010Note for Redundant Ethernet Interfaces: 5011======================================= 5012 5013Some boards come with redundant Ethernet interfaces; U-Boot supports 5014such configurations and is capable of automatic selection of a 5015"working" interface when needed. MAC assignment works as follows: 5016 5017Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5018MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5019"eth1addr" (=>eth1), "eth2addr", ... 5020 5021If the network interface stores some valid MAC address (for instance 5022in SROM), this is used as default address if there is NO correspon- 5023ding setting in the environment; if the corresponding environment 5024variable is set, this overrides the settings in the card; that means: 5025 5026o If the SROM has a valid MAC address, and there is no address in the 5027 environment, the SROM's address is used. 5028 5029o If there is no valid address in the SROM, and a definition in the 5030 environment exists, then the value from the environment variable is 5031 used. 5032 5033o If both the SROM and the environment contain a MAC address, and 5034 both addresses are the same, this MAC address is used. 5035 5036o If both the SROM and the environment contain a MAC address, and the 5037 addresses differ, the value from the environment is used and a 5038 warning is printed. 5039 5040o If neither SROM nor the environment contain a MAC address, an error 5041 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5042 a random, locally-assigned MAC is used. 5043 5044If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5045will be programmed into hardware as part of the initialization process. This 5046may be skipped by setting the appropriate 'ethmacskip' environment variable. 5047The naming convention is as follows: 5048"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5049 5050Image Formats: 5051============== 5052 5053U-Boot is capable of booting (and performing other auxiliary operations on) 5054images in two formats: 5055 5056New uImage format (FIT) 5057----------------------- 5058 5059Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5060to Flattened Device Tree). It allows the use of images with multiple 5061components (several kernels, ramdisks, etc.), with contents protected by 5062SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5063 5064 5065Old uImage format 5066----------------- 5067 5068Old image format is based on binary files which can be basically anything, 5069preceded by a special header; see the definitions in include/image.h for 5070details; basically, the header defines the following image properties: 5071 5072* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5073 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5074 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5075 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5076 INTEGRITY). 5077* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5078 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5079 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5080* Compression Type (uncompressed, gzip, bzip2) 5081* Load Address 5082* Entry Point 5083* Image Name 5084* Image Timestamp 5085 5086The header is marked by a special Magic Number, and both the header 5087and the data portions of the image are secured against corruption by 5088CRC32 checksums. 5089 5090 5091Linux Support: 5092============== 5093 5094Although U-Boot should support any OS or standalone application 5095easily, the main focus has always been on Linux during the design of 5096U-Boot. 5097 5098U-Boot includes many features that so far have been part of some 5099special "boot loader" code within the Linux kernel. Also, any 5100"initrd" images to be used are no longer part of one big Linux image; 5101instead, kernel and "initrd" are separate images. This implementation 5102serves several purposes: 5103 5104- the same features can be used for other OS or standalone 5105 applications (for instance: using compressed images to reduce the 5106 Flash memory footprint) 5107 5108- it becomes much easier to port new Linux kernel versions because 5109 lots of low-level, hardware dependent stuff are done by U-Boot 5110 5111- the same Linux kernel image can now be used with different "initrd" 5112 images; of course this also means that different kernel images can 5113 be run with the same "initrd". This makes testing easier (you don't 5114 have to build a new "zImage.initrd" Linux image when you just 5115 change a file in your "initrd"). Also, a field-upgrade of the 5116 software is easier now. 5117 5118 5119Linux HOWTO: 5120============ 5121 5122Porting Linux to U-Boot based systems: 5123--------------------------------------- 5124 5125U-Boot cannot save you from doing all the necessary modifications to 5126configure the Linux device drivers for use with your target hardware 5127(no, we don't intend to provide a full virtual machine interface to 5128Linux :-). 5129 5130But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5131 5132Just make sure your machine specific header file (for instance 5133include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5134Information structure as we define in include/asm-<arch>/u-boot.h, 5135and make sure that your definition of IMAP_ADDR uses the same value 5136as your U-Boot configuration in CONFIG_SYS_IMMR. 5137 5138Note that U-Boot now has a driver model, a unified model for drivers. 5139If you are adding a new driver, plumb it into driver model. If there 5140is no uclass available, you are encouraged to create one. See 5141doc/driver-model. 5142 5143 5144Configuring the Linux kernel: 5145----------------------------- 5146 5147No specific requirements for U-Boot. Make sure you have some root 5148device (initial ramdisk, NFS) for your target system. 5149 5150 5151Building a Linux Image: 5152----------------------- 5153 5154With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5155not used. If you use recent kernel source, a new build target 5156"uImage" will exist which automatically builds an image usable by 5157U-Boot. Most older kernels also have support for a "pImage" target, 5158which was introduced for our predecessor project PPCBoot and uses a 5159100% compatible format. 5160 5161Example: 5162 5163 make TQM850L_defconfig 5164 make oldconfig 5165 make dep 5166 make uImage 5167 5168The "uImage" build target uses a special tool (in 'tools/mkimage') to 5169encapsulate a compressed Linux kernel image with header information, 5170CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5171 5172* build a standard "vmlinux" kernel image (in ELF binary format): 5173 5174* convert the kernel into a raw binary image: 5175 5176 ${CROSS_COMPILE}-objcopy -O binary \ 5177 -R .note -R .comment \ 5178 -S vmlinux linux.bin 5179 5180* compress the binary image: 5181 5182 gzip -9 linux.bin 5183 5184* package compressed binary image for U-Boot: 5185 5186 mkimage -A ppc -O linux -T kernel -C gzip \ 5187 -a 0 -e 0 -n "Linux Kernel Image" \ 5188 -d linux.bin.gz uImage 5189 5190 5191The "mkimage" tool can also be used to create ramdisk images for use 5192with U-Boot, either separated from the Linux kernel image, or 5193combined into one file. "mkimage" encapsulates the images with a 64 5194byte header containing information about target architecture, 5195operating system, image type, compression method, entry points, time 5196stamp, CRC32 checksums, etc. 5197 5198"mkimage" can be called in two ways: to verify existing images and 5199print the header information, or to build new images. 5200 5201In the first form (with "-l" option) mkimage lists the information 5202contained in the header of an existing U-Boot image; this includes 5203checksum verification: 5204 5205 tools/mkimage -l image 5206 -l ==> list image header information 5207 5208The second form (with "-d" option) is used to build a U-Boot image 5209from a "data file" which is used as image payload: 5210 5211 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5212 -n name -d data_file image 5213 -A ==> set architecture to 'arch' 5214 -O ==> set operating system to 'os' 5215 -T ==> set image type to 'type' 5216 -C ==> set compression type 'comp' 5217 -a ==> set load address to 'addr' (hex) 5218 -e ==> set entry point to 'ep' (hex) 5219 -n ==> set image name to 'name' 5220 -d ==> use image data from 'datafile' 5221 5222Right now, all Linux kernels for PowerPC systems use the same load 5223address (0x00000000), but the entry point address depends on the 5224kernel version: 5225 5226- 2.2.x kernels have the entry point at 0x0000000C, 5227- 2.3.x and later kernels have the entry point at 0x00000000. 5228 5229So a typical call to build a U-Boot image would read: 5230 5231 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5232 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5233 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5234 > examples/uImage.TQM850L 5235 Image Name: 2.4.4 kernel for TQM850L 5236 Created: Wed Jul 19 02:34:59 2000 5237 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5238 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5239 Load Address: 0x00000000 5240 Entry Point: 0x00000000 5241 5242To verify the contents of the image (or check for corruption): 5243 5244 -> tools/mkimage -l examples/uImage.TQM850L 5245 Image Name: 2.4.4 kernel for TQM850L 5246 Created: Wed Jul 19 02:34:59 2000 5247 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5248 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5249 Load Address: 0x00000000 5250 Entry Point: 0x00000000 5251 5252NOTE: for embedded systems where boot time is critical you can trade 5253speed for memory and install an UNCOMPRESSED image instead: this 5254needs more space in Flash, but boots much faster since it does not 5255need to be uncompressed: 5256 5257 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5258 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5259 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5260 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5261 > examples/uImage.TQM850L-uncompressed 5262 Image Name: 2.4.4 kernel for TQM850L 5263 Created: Wed Jul 19 02:34:59 2000 5264 Image Type: PowerPC Linux Kernel Image (uncompressed) 5265 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5266 Load Address: 0x00000000 5267 Entry Point: 0x00000000 5268 5269 5270Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5271when your kernel is intended to use an initial ramdisk: 5272 5273 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5274 > -A ppc -O linux -T ramdisk -C gzip \ 5275 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5276 Image Name: Simple Ramdisk Image 5277 Created: Wed Jan 12 14:01:50 2000 5278 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5279 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5280 Load Address: 0x00000000 5281 Entry Point: 0x00000000 5282 5283The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5284option performs the converse operation of the mkimage's second form (the "-d" 5285option). Given an image built by mkimage, the dumpimage extracts a "data file" 5286from the image: 5287 5288 tools/dumpimage -i image -T type -p position data_file 5289 -i ==> extract from the 'image' a specific 'data_file' 5290 -T ==> set image type to 'type' 5291 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5292 5293 5294Installing a Linux Image: 5295------------------------- 5296 5297To downloading a U-Boot image over the serial (console) interface, 5298you must convert the image to S-Record format: 5299 5300 objcopy -I binary -O srec examples/image examples/image.srec 5301 5302The 'objcopy' does not understand the information in the U-Boot 5303image header, so the resulting S-Record file will be relative to 5304address 0x00000000. To load it to a given address, you need to 5305specify the target address as 'offset' parameter with the 'loads' 5306command. 5307 5308Example: install the image to address 0x40100000 (which on the 5309TQM8xxL is in the first Flash bank): 5310 5311 => erase 40100000 401FFFFF 5312 5313 .......... done 5314 Erased 8 sectors 5315 5316 => loads 40100000 5317 ## Ready for S-Record download ... 5318 ~>examples/image.srec 5319 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5320 ... 5321 15989 15990 15991 15992 5322 [file transfer complete] 5323 [connected] 5324 ## Start Addr = 0x00000000 5325 5326 5327You can check the success of the download using the 'iminfo' command; 5328this includes a checksum verification so you can be sure no data 5329corruption happened: 5330 5331 => imi 40100000 5332 5333 ## Checking Image at 40100000 ... 5334 Image Name: 2.2.13 for initrd on TQM850L 5335 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5336 Data Size: 335725 Bytes = 327 kB = 0 MB 5337 Load Address: 00000000 5338 Entry Point: 0000000c 5339 Verifying Checksum ... OK 5340 5341 5342Boot Linux: 5343----------- 5344 5345The "bootm" command is used to boot an application that is stored in 5346memory (RAM or Flash). In case of a Linux kernel image, the contents 5347of the "bootargs" environment variable is passed to the kernel as 5348parameters. You can check and modify this variable using the 5349"printenv" and "setenv" commands: 5350 5351 5352 => printenv bootargs 5353 bootargs=root=/dev/ram 5354 5355 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5356 5357 => printenv bootargs 5358 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5359 5360 => bootm 40020000 5361 ## Booting Linux kernel at 40020000 ... 5362 Image Name: 2.2.13 for NFS on TQM850L 5363 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5364 Data Size: 381681 Bytes = 372 kB = 0 MB 5365 Load Address: 00000000 5366 Entry Point: 0000000c 5367 Verifying Checksum ... OK 5368 Uncompressing Kernel Image ... OK 5369 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 5370 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5371 time_init: decrementer frequency = 187500000/60 5372 Calibrating delay loop... 49.77 BogoMIPS 5373 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5374 ... 5375 5376If you want to boot a Linux kernel with initial RAM disk, you pass 5377the memory addresses of both the kernel and the initrd image (PPBCOOT 5378format!) to the "bootm" command: 5379 5380 => imi 40100000 40200000 5381 5382 ## Checking Image at 40100000 ... 5383 Image Name: 2.2.13 for initrd on TQM850L 5384 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5385 Data Size: 335725 Bytes = 327 kB = 0 MB 5386 Load Address: 00000000 5387 Entry Point: 0000000c 5388 Verifying Checksum ... OK 5389 5390 ## Checking Image at 40200000 ... 5391 Image Name: Simple Ramdisk Image 5392 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5393 Data Size: 566530 Bytes = 553 kB = 0 MB 5394 Load Address: 00000000 5395 Entry Point: 00000000 5396 Verifying Checksum ... OK 5397 5398 => bootm 40100000 40200000 5399 ## Booting Linux kernel at 40100000 ... 5400 Image Name: 2.2.13 for initrd on TQM850L 5401 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5402 Data Size: 335725 Bytes = 327 kB = 0 MB 5403 Load Address: 00000000 5404 Entry Point: 0000000c 5405 Verifying Checksum ... OK 5406 Uncompressing Kernel Image ... OK 5407 ## Loading RAMDisk Image at 40200000 ... 5408 Image Name: Simple Ramdisk Image 5409 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5410 Data Size: 566530 Bytes = 553 kB = 0 MB 5411 Load Address: 00000000 5412 Entry Point: 00000000 5413 Verifying Checksum ... OK 5414 Loading Ramdisk ... OK 5415 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 5416 Boot arguments: root=/dev/ram 5417 time_init: decrementer frequency = 187500000/60 5418 Calibrating delay loop... 49.77 BogoMIPS 5419 ... 5420 RAMDISK: Compressed image found at block 0 5421 VFS: Mounted root (ext2 filesystem). 5422 5423 bash# 5424 5425Boot Linux and pass a flat device tree: 5426----------- 5427 5428First, U-Boot must be compiled with the appropriate defines. See the section 5429titled "Linux Kernel Interface" above for a more in depth explanation. The 5430following is an example of how to start a kernel and pass an updated 5431flat device tree: 5432 5433=> print oftaddr 5434oftaddr=0x300000 5435=> print oft 5436oft=oftrees/mpc8540ads.dtb 5437=> tftp $oftaddr $oft 5438Speed: 1000, full duplex 5439Using TSEC0 device 5440TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5441Filename 'oftrees/mpc8540ads.dtb'. 5442Load address: 0x300000 5443Loading: # 5444done 5445Bytes transferred = 4106 (100a hex) 5446=> tftp $loadaddr $bootfile 5447Speed: 1000, full duplex 5448Using TSEC0 device 5449TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5450Filename 'uImage'. 5451Load address: 0x200000 5452Loading:############ 5453done 5454Bytes transferred = 1029407 (fb51f hex) 5455=> print loadaddr 5456loadaddr=200000 5457=> print oftaddr 5458oftaddr=0x300000 5459=> bootm $loadaddr - $oftaddr 5460## Booting image at 00200000 ... 5461 Image Name: Linux-2.6.17-dirty 5462 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5463 Data Size: 1029343 Bytes = 1005.2 kB 5464 Load Address: 00000000 5465 Entry Point: 00000000 5466 Verifying Checksum ... OK 5467 Uncompressing Kernel Image ... OK 5468Booting using flat device tree at 0x300000 5469Using MPC85xx ADS machine description 5470Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5471[snip] 5472 5473 5474More About U-Boot Image Types: 5475------------------------------ 5476 5477U-Boot supports the following image types: 5478 5479 "Standalone Programs" are directly runnable in the environment 5480 provided by U-Boot; it is expected that (if they behave 5481 well) you can continue to work in U-Boot after return from 5482 the Standalone Program. 5483 "OS Kernel Images" are usually images of some Embedded OS which 5484 will take over control completely. Usually these programs 5485 will install their own set of exception handlers, device 5486 drivers, set up the MMU, etc. - this means, that you cannot 5487 expect to re-enter U-Boot except by resetting the CPU. 5488 "RAMDisk Images" are more or less just data blocks, and their 5489 parameters (address, size) are passed to an OS kernel that is 5490 being started. 5491 "Multi-File Images" contain several images, typically an OS 5492 (Linux) kernel image and one or more data images like 5493 RAMDisks. This construct is useful for instance when you want 5494 to boot over the network using BOOTP etc., where the boot 5495 server provides just a single image file, but you want to get 5496 for instance an OS kernel and a RAMDisk image. 5497 5498 "Multi-File Images" start with a list of image sizes, each 5499 image size (in bytes) specified by an "uint32_t" in network 5500 byte order. This list is terminated by an "(uint32_t)0". 5501 Immediately after the terminating 0 follow the images, one by 5502 one, all aligned on "uint32_t" boundaries (size rounded up to 5503 a multiple of 4 bytes). 5504 5505 "Firmware Images" are binary images containing firmware (like 5506 U-Boot or FPGA images) which usually will be programmed to 5507 flash memory. 5508 5509 "Script files" are command sequences that will be executed by 5510 U-Boot's command interpreter; this feature is especially 5511 useful when you configure U-Boot to use a real shell (hush) 5512 as command interpreter. 5513 5514Booting the Linux zImage: 5515------------------------- 5516 5517On some platforms, it's possible to boot Linux zImage. This is done 5518using the "bootz" command. The syntax of "bootz" command is the same 5519as the syntax of "bootm" command. 5520 5521Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5522kernel with raw initrd images. The syntax is slightly different, the 5523address of the initrd must be augmented by it's size, in the following 5524format: "<initrd addres>:<initrd size>". 5525 5526 5527Standalone HOWTO: 5528================= 5529 5530One of the features of U-Boot is that you can dynamically load and 5531run "standalone" applications, which can use some resources of 5532U-Boot like console I/O functions or interrupt services. 5533 5534Two simple examples are included with the sources: 5535 5536"Hello World" Demo: 5537------------------- 5538 5539'examples/hello_world.c' contains a small "Hello World" Demo 5540application; it is automatically compiled when you build U-Boot. 5541It's configured to run at address 0x00040004, so you can play with it 5542like that: 5543 5544 => loads 5545 ## Ready for S-Record download ... 5546 ~>examples/hello_world.srec 5547 1 2 3 4 5 6 7 8 9 10 11 ... 5548 [file transfer complete] 5549 [connected] 5550 ## Start Addr = 0x00040004 5551 5552 => go 40004 Hello World! This is a test. 5553 ## Starting application at 0x00040004 ... 5554 Hello World 5555 argc = 7 5556 argv[0] = "40004" 5557 argv[1] = "Hello" 5558 argv[2] = "World!" 5559 argv[3] = "This" 5560 argv[4] = "is" 5561 argv[5] = "a" 5562 argv[6] = "test." 5563 argv[7] = "<NULL>" 5564 Hit any key to exit ... 5565 5566 ## Application terminated, rc = 0x0 5567 5568Another example, which demonstrates how to register a CPM interrupt 5569handler with the U-Boot code, can be found in 'examples/timer.c'. 5570Here, a CPM timer is set up to generate an interrupt every second. 5571The interrupt service routine is trivial, just printing a '.' 5572character, but this is just a demo program. The application can be 5573controlled by the following keys: 5574 5575 ? - print current values og the CPM Timer registers 5576 b - enable interrupts and start timer 5577 e - stop timer and disable interrupts 5578 q - quit application 5579 5580 => loads 5581 ## Ready for S-Record download ... 5582 ~>examples/timer.srec 5583 1 2 3 4 5 6 7 8 9 10 11 ... 5584 [file transfer complete] 5585 [connected] 5586 ## Start Addr = 0x00040004 5587 5588 => go 40004 5589 ## Starting application at 0x00040004 ... 5590 TIMERS=0xfff00980 5591 Using timer 1 5592 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5593 5594Hit 'b': 5595 [q, b, e, ?] Set interval 1000000 us 5596 Enabling timer 5597Hit '?': 5598 [q, b, e, ?] ........ 5599 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5600Hit '?': 5601 [q, b, e, ?] . 5602 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5603Hit '?': 5604 [q, b, e, ?] . 5605 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5606Hit '?': 5607 [q, b, e, ?] . 5608 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5609Hit 'e': 5610 [q, b, e, ?] ...Stopping timer 5611Hit 'q': 5612 [q, b, e, ?] ## Application terminated, rc = 0x0 5613 5614 5615Minicom warning: 5616================ 5617 5618Over time, many people have reported problems when trying to use the 5619"minicom" terminal emulation program for serial download. I (wd) 5620consider minicom to be broken, and recommend not to use it. Under 5621Unix, I recommend to use C-Kermit for general purpose use (and 5622especially for kermit binary protocol download ("loadb" command), and 5623use "cu" for S-Record download ("loads" command). See 5624http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5625for help with kermit. 5626 5627 5628Nevertheless, if you absolutely want to use it try adding this 5629configuration to your "File transfer protocols" section: 5630 5631 Name Program Name U/D FullScr IO-Red. Multi 5632 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5633 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5634 5635 5636NetBSD Notes: 5637============= 5638 5639Starting at version 0.9.2, U-Boot supports NetBSD both as host 5640(build U-Boot) and target system (boots NetBSD/mpc8xx). 5641 5642Building requires a cross environment; it is known to work on 5643NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5644need gmake since the Makefiles are not compatible with BSD make). 5645Note that the cross-powerpc package does not install include files; 5646attempting to build U-Boot will fail because <machine/ansi.h> is 5647missing. This file has to be installed and patched manually: 5648 5649 # cd /usr/pkg/cross/powerpc-netbsd/include 5650 # mkdir powerpc 5651 # ln -s powerpc machine 5652 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5653 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5654 5655Native builds *don't* work due to incompatibilities between native 5656and U-Boot include files. 5657 5658Booting assumes that (the first part of) the image booted is a 5659stage-2 loader which in turn loads and then invokes the kernel 5660proper. Loader sources will eventually appear in the NetBSD source 5661tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5662meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5663 5664 5665Implementation Internals: 5666========================= 5667 5668The following is not intended to be a complete description of every 5669implementation detail. However, it should help to understand the 5670inner workings of U-Boot and make it easier to port it to custom 5671hardware. 5672 5673 5674Initial Stack, Global Data: 5675--------------------------- 5676 5677The implementation of U-Boot is complicated by the fact that U-Boot 5678starts running out of ROM (flash memory), usually without access to 5679system RAM (because the memory controller is not initialized yet). 5680This means that we don't have writable Data or BSS segments, and BSS 5681is not initialized as zero. To be able to get a C environment working 5682at all, we have to allocate at least a minimal stack. Implementation 5683options for this are defined and restricted by the CPU used: Some CPU 5684models provide on-chip memory (like the IMMR area on MPC8xx and 5685MPC826x processors), on others (parts of) the data cache can be 5686locked as (mis-) used as memory, etc. 5687 5688 Chris Hallinan posted a good summary of these issues to the 5689 U-Boot mailing list: 5690 5691 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5692 From: "Chris Hallinan" <clh@net1plus.com> 5693 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5694 ... 5695 5696 Correct me if I'm wrong, folks, but the way I understand it 5697 is this: Using DCACHE as initial RAM for Stack, etc, does not 5698 require any physical RAM backing up the cache. The cleverness 5699 is that the cache is being used as a temporary supply of 5700 necessary storage before the SDRAM controller is setup. It's 5701 beyond the scope of this list to explain the details, but you 5702 can see how this works by studying the cache architecture and 5703 operation in the architecture and processor-specific manuals. 5704 5705 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5706 is another option for the system designer to use as an 5707 initial stack/RAM area prior to SDRAM being available. Either 5708 option should work for you. Using CS 4 should be fine if your 5709 board designers haven't used it for something that would 5710 cause you grief during the initial boot! It is frequently not 5711 used. 5712 5713 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5714 with your processor/board/system design. The default value 5715 you will find in any recent u-boot distribution in 5716 walnut.h should work for you. I'd set it to a value larger 5717 than your SDRAM module. If you have a 64MB SDRAM module, set 5718 it above 400_0000. Just make sure your board has no resources 5719 that are supposed to respond to that address! That code in 5720 start.S has been around a while and should work as is when 5721 you get the config right. 5722 5723 -Chris Hallinan 5724 DS4.COM, Inc. 5725 5726It is essential to remember this, since it has some impact on the C 5727code for the initialization procedures: 5728 5729* Initialized global data (data segment) is read-only. Do not attempt 5730 to write it. 5731 5732* Do not use any uninitialized global data (or implicitly initialized 5733 as zero data - BSS segment) at all - this is undefined, initiali- 5734 zation is performed later (when relocating to RAM). 5735 5736* Stack space is very limited. Avoid big data buffers or things like 5737 that. 5738 5739Having only the stack as writable memory limits means we cannot use 5740normal global data to share information between the code. But it 5741turned out that the implementation of U-Boot can be greatly 5742simplified by making a global data structure (gd_t) available to all 5743functions. We could pass a pointer to this data as argument to _all_ 5744functions, but this would bloat the code. Instead we use a feature of 5745the GCC compiler (Global Register Variables) to share the data: we 5746place a pointer (gd) to the global data into a register which we 5747reserve for this purpose. 5748 5749When choosing a register for such a purpose we are restricted by the 5750relevant (E)ABI specifications for the current architecture, and by 5751GCC's implementation. 5752 5753For PowerPC, the following registers have specific use: 5754 R1: stack pointer 5755 R2: reserved for system use 5756 R3-R4: parameter passing and return values 5757 R5-R10: parameter passing 5758 R13: small data area pointer 5759 R30: GOT pointer 5760 R31: frame pointer 5761 5762 (U-Boot also uses R12 as internal GOT pointer. r12 5763 is a volatile register so r12 needs to be reset when 5764 going back and forth between asm and C) 5765 5766 ==> U-Boot will use R2 to hold a pointer to the global data 5767 5768 Note: on PPC, we could use a static initializer (since the 5769 address of the global data structure is known at compile time), 5770 but it turned out that reserving a register results in somewhat 5771 smaller code - although the code savings are not that big (on 5772 average for all boards 752 bytes for the whole U-Boot image, 5773 624 text + 127 data). 5774 5775On ARM, the following registers are used: 5776 5777 R0: function argument word/integer result 5778 R1-R3: function argument word 5779 R9: platform specific 5780 R10: stack limit (used only if stack checking is enabled) 5781 R11: argument (frame) pointer 5782 R12: temporary workspace 5783 R13: stack pointer 5784 R14: link register 5785 R15: program counter 5786 5787 ==> U-Boot will use R9 to hold a pointer to the global data 5788 5789 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5790 5791On Nios II, the ABI is documented here: 5792 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5793 5794 ==> U-Boot will use gp to hold a pointer to the global data 5795 5796 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5797 to access small data sections, so gp is free. 5798 5799On NDS32, the following registers are used: 5800 5801 R0-R1: argument/return 5802 R2-R5: argument 5803 R15: temporary register for assembler 5804 R16: trampoline register 5805 R28: frame pointer (FP) 5806 R29: global pointer (GP) 5807 R30: link register (LP) 5808 R31: stack pointer (SP) 5809 PC: program counter (PC) 5810 5811 ==> U-Boot will use R10 to hold a pointer to the global data 5812 5813NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5814or current versions of GCC may "optimize" the code too much. 5815 5816Memory Management: 5817------------------ 5818 5819U-Boot runs in system state and uses physical addresses, i.e. the 5820MMU is not used either for address mapping nor for memory protection. 5821 5822The available memory is mapped to fixed addresses using the memory 5823controller. In this process, a contiguous block is formed for each 5824memory type (Flash, SDRAM, SRAM), even when it consists of several 5825physical memory banks. 5826 5827U-Boot is installed in the first 128 kB of the first Flash bank (on 5828TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5829booting and sizing and initializing DRAM, the code relocates itself 5830to the upper end of DRAM. Immediately below the U-Boot code some 5831memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5832configuration setting]. Below that, a structure with global Board 5833Info data is placed, followed by the stack (growing downward). 5834 5835Additionally, some exception handler code is copied to the low 8 kB 5836of DRAM (0x00000000 ... 0x00001FFF). 5837 5838So a typical memory configuration with 16 MB of DRAM could look like 5839this: 5840 5841 0x0000 0000 Exception Vector code 5842 : 5843 0x0000 1FFF 5844 0x0000 2000 Free for Application Use 5845 : 5846 : 5847 5848 : 5849 : 5850 0x00FB FF20 Monitor Stack (Growing downward) 5851 0x00FB FFAC Board Info Data and permanent copy of global data 5852 0x00FC 0000 Malloc Arena 5853 : 5854 0x00FD FFFF 5855 0x00FE 0000 RAM Copy of Monitor Code 5856 ... eventually: LCD or video framebuffer 5857 ... eventually: pRAM (Protected RAM - unchanged by reset) 5858 0x00FF FFFF [End of RAM] 5859 5860 5861System Initialization: 5862---------------------- 5863 5864In the reset configuration, U-Boot starts at the reset entry point 5865(on most PowerPC systems at address 0x00000100). Because of the reset 5866configuration for CS0# this is a mirror of the on board Flash memory. 5867To be able to re-map memory U-Boot then jumps to its link address. 5868To be able to implement the initialization code in C, a (small!) 5869initial stack is set up in the internal Dual Ported RAM (in case CPUs 5870which provide such a feature like MPC8xx or MPC8260), or in a locked 5871part of the data cache. After that, U-Boot initializes the CPU core, 5872the caches and the SIU. 5873 5874Next, all (potentially) available memory banks are mapped using a 5875preliminary mapping. For example, we put them on 512 MB boundaries 5876(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5877on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5878programmed for SDRAM access. Using the temporary configuration, a 5879simple memory test is run that determines the size of the SDRAM 5880banks. 5881 5882When there is more than one SDRAM bank, and the banks are of 5883different size, the largest is mapped first. For equal size, the first 5884bank (CS2#) is mapped first. The first mapping is always for address 58850x00000000, with any additional banks following immediately to create 5886contiguous memory starting from 0. 5887 5888Then, the monitor installs itself at the upper end of the SDRAM area 5889and allocates memory for use by malloc() and for the global Board 5890Info data; also, the exception vector code is copied to the low RAM 5891pages, and the final stack is set up. 5892 5893Only after this relocation will you have a "normal" C environment; 5894until that you are restricted in several ways, mostly because you are 5895running from ROM, and because the code will have to be relocated to a 5896new address in RAM. 5897 5898 5899U-Boot Porting Guide: 5900---------------------- 5901 5902[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5903list, October 2002] 5904 5905 5906int main(int argc, char *argv[]) 5907{ 5908 sighandler_t no_more_time; 5909 5910 signal(SIGALRM, no_more_time); 5911 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5912 5913 if (available_money > available_manpower) { 5914 Pay consultant to port U-Boot; 5915 return 0; 5916 } 5917 5918 Download latest U-Boot source; 5919 5920 Subscribe to u-boot mailing list; 5921 5922 if (clueless) 5923 email("Hi, I am new to U-Boot, how do I get started?"); 5924 5925 while (learning) { 5926 Read the README file in the top level directory; 5927 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5928 Read applicable doc/*.README; 5929 Read the source, Luke; 5930 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5931 } 5932 5933 if (available_money > toLocalCurrency ($2500)) 5934 Buy a BDI3000; 5935 else 5936 Add a lot of aggravation and time; 5937 5938 if (a similar board exists) { /* hopefully... */ 5939 cp -a board/<similar> board/<myboard> 5940 cp include/configs/<similar>.h include/configs/<myboard>.h 5941 } else { 5942 Create your own board support subdirectory; 5943 Create your own board include/configs/<myboard>.h file; 5944 } 5945 Edit new board/<myboard> files 5946 Edit new include/configs/<myboard>.h 5947 5948 while (!accepted) { 5949 while (!running) { 5950 do { 5951 Add / modify source code; 5952 } until (compiles); 5953 Debug; 5954 if (clueless) 5955 email("Hi, I am having problems..."); 5956 } 5957 Send patch file to the U-Boot email list; 5958 if (reasonable critiques) 5959 Incorporate improvements from email list code review; 5960 else 5961 Defend code as written; 5962 } 5963 5964 return 0; 5965} 5966 5967void no_more_time (int sig) 5968{ 5969 hire_a_guru(); 5970} 5971 5972 5973Coding Standards: 5974----------------- 5975 5976All contributions to U-Boot should conform to the Linux kernel 5977coding style; see the file "Documentation/CodingStyle" and the script 5978"scripts/Lindent" in your Linux kernel source directory. 5979 5980Source files originating from a different project (for example the 5981MTD subsystem) are generally exempt from these guidelines and are not 5982reformatted to ease subsequent migration to newer versions of those 5983sources. 5984 5985Please note that U-Boot is implemented in C (and to some small parts in 5986Assembler); no C++ is used, so please do not use C++ style comments (//) 5987in your code. 5988 5989Please also stick to the following formatting rules: 5990- remove any trailing white space 5991- use TAB characters for indentation and vertical alignment, not spaces 5992- make sure NOT to use DOS '\r\n' line feeds 5993- do not add more than 2 consecutive empty lines to source files 5994- do not add trailing empty lines to source files 5995 5996Submissions which do not conform to the standards may be returned 5997with a request to reformat the changes. 5998 5999 6000Submitting Patches: 6001------------------- 6002 6003Since the number of patches for U-Boot is growing, we need to 6004establish some rules. Submissions which do not conform to these rules 6005may be rejected, even when they contain important and valuable stuff. 6006 6007Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6008 6009Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6010see http://lists.denx.de/mailman/listinfo/u-boot 6011 6012When you send a patch, please include the following information with 6013it: 6014 6015* For bug fixes: a description of the bug and how your patch fixes 6016 this bug. Please try to include a way of demonstrating that the 6017 patch actually fixes something. 6018 6019* For new features: a description of the feature and your 6020 implementation. 6021 6022* A CHANGELOG entry as plaintext (separate from the patch) 6023 6024* For major contributions, add a MAINTAINERS file with your 6025 information and associated file and directory references. 6026 6027* When you add support for a new board, don't forget to add a 6028 maintainer e-mail address to the boards.cfg file, too. 6029 6030* If your patch adds new configuration options, don't forget to 6031 document these in the README file. 6032 6033* The patch itself. If you are using git (which is *strongly* 6034 recommended) you can easily generate the patch using the 6035 "git format-patch". If you then use "git send-email" to send it to 6036 the U-Boot mailing list, you will avoid most of the common problems 6037 with some other mail clients. 6038 6039 If you cannot use git, use "diff -purN OLD NEW". If your version of 6040 diff does not support these options, then get the latest version of 6041 GNU diff. 6042 6043 The current directory when running this command shall be the parent 6044 directory of the U-Boot source tree (i. e. please make sure that 6045 your patch includes sufficient directory information for the 6046 affected files). 6047 6048 We prefer patches as plain text. MIME attachments are discouraged, 6049 and compressed attachments must not be used. 6050 6051* If one logical set of modifications affects or creates several 6052 files, all these changes shall be submitted in a SINGLE patch file. 6053 6054* Changesets that contain different, unrelated modifications shall be 6055 submitted as SEPARATE patches, one patch per changeset. 6056 6057 6058Notes: 6059 6060* Before sending the patch, run the buildman script on your patched 6061 source tree and make sure that no errors or warnings are reported 6062 for any of the boards. 6063 6064* Keep your modifications to the necessary minimum: A patch 6065 containing several unrelated changes or arbitrary reformats will be 6066 returned with a request to re-formatting / split it. 6067 6068* If you modify existing code, make sure that your new code does not 6069 add to the memory footprint of the code ;-) Small is beautiful! 6070 When adding new features, these should compile conditionally only 6071 (using #ifdef), and the resulting code with the new feature 6072 disabled must not need more memory than the old code without your 6073 modification. 6074 6075* Remember that there is a size limit of 100 kB per message on the 6076 u-boot mailing list. Bigger patches will be moderated. If they are 6077 reasonable and not too big, they will be acknowledged. But patches 6078 bigger than the size limit should be avoided. 6079