#
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# (C) Copyright 2000 - 2013
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# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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#
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# SPDX-License-Identifier: GPL-2.0+
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#
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Summary:
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========
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This directory contains the source code for U-Boot, a boot loader for
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Embedded boards based on PowerPC, ARM, MIPS and several other
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processors, which can be installed in a boot ROM and used to
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initialize and test the hardware or to download and run application
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code.
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The development of U-Boot is closely related to Linux: some parts of
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the source code originate in the Linux source tree, we have some
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header files in common, and special provision has been made to
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support booting of Linux images.
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Some attention has been paid to make this software easily
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configurable and extendable. For instance, all monitor commands are
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implemented with the same call interface, so that it's very easy to
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add new commands. Also, instead of permanently adding rarely used
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code (for instance hardware test utilities) to the monitor, you can
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load and run it dynamically.
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Status:
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=======
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In general, all boards for which a configuration option exists in the
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Makefile have been tested to some extent and can be considered
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"working". In fact, many of them are used in production systems.
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In case of problems see the CHANGELOG file to find out who contributed
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the specific port. In addition, there are various MAINTAINERS files
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scattered throughout the U-Boot source identifying the people or
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companies responsible for various boards and subsystems.
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Note: As of August, 2010, there is no longer a CHANGELOG file in the
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actual U-Boot source tree; however, it can be created dynamically
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from the Git log using:
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make CHANGELOG
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Where to get help:
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==================
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In case you have questions about, problems with or contributions for
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U-Boot, you should send a message to the U-Boot mailing list at
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<u-boot@lists.denx.de>. There is also an archive of previous traffic
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on the mailing list - please search the archive before asking FAQ's.
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Please see http://lists.denx.de/pipermail/u-boot and
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http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
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Where to get source code:
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=========================
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The U-Boot source code is maintained in the Git repository at
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git://www.denx.de/git/u-boot.git ; you can browse it online at
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http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
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The "snapshot" links on this page allow you to download tarballs of
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any version you might be interested in. Official releases are also
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available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
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directory.
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Pre-built (and tested) images are available from
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ftp://ftp.denx.de/pub/u-boot/images/
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Where we come from:
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===================
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- start from 8xxrom sources
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- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
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- clean up code
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- make it easier to add custom boards
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- make it possible to add other [PowerPC] CPUs
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- extend functions, especially:
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* Provide extended interface to Linux boot loader
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* S-Record download
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* network boot
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* PCMCIA / CompactFlash / ATA disk / SCSI ... boot
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- create ARMBoot project (http://sourceforge.net/projects/armboot)
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- add other CPU families (starting with ARM)
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- create U-Boot project (http://sourceforge.net/projects/u-boot)
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- current project page: see http://www.denx.de/wiki/U-Boot
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Names and Spelling:
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===================
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The "official" name of this project is "Das U-Boot". The spelling
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"U-Boot" shall be used in all written text (documentation, comments
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in source files etc.). Example:
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This is the README file for the U-Boot project.
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File names etc. shall be based on the string "u-boot". Examples:
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include/asm-ppc/u-boot.h
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#include <asm/u-boot.h>
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Variable names, preprocessor constants etc. shall be either based on
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the string "u_boot" or on "U_BOOT". Example:
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U_BOOT_VERSION u_boot_logo
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IH_OS_U_BOOT u_boot_hush_start
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Versioning:
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===========
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Starting with the release in October 2008, the names of the releases
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were changed from numerical release numbers without deeper meaning
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into a time stamp based numbering. Regular releases are identified by
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names consisting of the calendar year and month of the release date.
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Additional fields (if present) indicate release candidates or bug fix
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releases in "stable" maintenance trees.
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Examples:
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U-Boot v2009.11 - Release November 2009
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U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
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U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
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Directory Hierarchy:
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====================
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/arch Architecture specific files
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/arc Files generic to ARC architecture
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/arm Files generic to ARM architecture
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/m68k Files generic to m68k architecture
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/microblaze Files generic to microblaze architecture
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/mips Files generic to MIPS architecture
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/nds32 Files generic to NDS32 architecture
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/nios2 Files generic to Altera NIOS2 architecture
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/openrisc Files generic to OpenRISC architecture
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/powerpc Files generic to PowerPC architecture
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/sandbox Files generic to HW-independent "sandbox"
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/sh Files generic to SH architecture
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/x86 Files generic to x86 architecture
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/api Machine/arch independent API for external apps
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/board Board dependent files
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/cmd U-Boot commands functions
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/common Misc architecture independent functions
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/configs Board default configuration files
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/disk Code for disk drive partition handling
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/doc Documentation (don't expect too much)
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/drivers Commonly used device drivers
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/dts Contains Makefile for building internal U-Boot fdt.
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/examples Example code for standalone applications, etc.
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/fs Filesystem code (cramfs, ext2, jffs2, etc.)
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/include Header Files
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/lib Library routines generic to all architectures
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/Licenses Various license files
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/net Networking code
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/post Power On Self Test
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/scripts Various build scripts and Makefiles
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/test Various unit test files
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/tools Tools to build S-Record or U-Boot images, etc.
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Software Configuration:
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=======================
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Configuration is usually done using C preprocessor defines; the
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rationale behind that is to avoid dead code whenever possible.
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There are two classes of configuration variables:
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* Configuration _OPTIONS_:
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These are selectable by the user and have names beginning with
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"CONFIG_".
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* Configuration _SETTINGS_:
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These depend on the hardware etc. and should not be meddled with if
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you don't know what you're doing; they have names beginning with
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"CONFIG_SYS_".
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Previously, all configuration was done by hand, which involved creating
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symbolic links and editing configuration files manually. More recently,
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U-Boot has added the Kbuild infrastructure used by the Linux kernel,
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allowing you to use the "make menuconfig" command to configure your
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build.
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Selection of Processor Architecture and Board Type:
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---------------------------------------------------
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For all supported boards there are ready-to-use default
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configurations available; just type "make <board_name>_defconfig".
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Example: For a TQM823L module type:
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cd u-boot
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make TQM823L_defconfig
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Note: If you're looking for the default configuration file for a board
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you're sure used to be there but is now missing, check the file
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doc/README.scrapyard for a list of no longer supported boards.
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Sandbox Environment:
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--------------------
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U-Boot can be built natively to run on a Linux host using the 'sandbox'
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board. This allows feature development which is not board- or architecture-
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specific to be undertaken on a native platform. The sandbox is also used to
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run some of U-Boot's tests.
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See board/sandbox/README.sandbox for more details.
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Board Initialisation Flow:
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--------------------------
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This is the intended start-up flow for boards. This should apply for both
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SPL and U-Boot proper (i.e. they both follow the same rules).
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Note: "SPL" stands for "Secondary Program Loader," which is explained in
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more detail later in this file.
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At present, SPL mostly uses a separate code path, but the function names
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and roles of each function are the same. Some boards or architectures
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may not conform to this. At least most ARM boards which use
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CONFIG_SPL_FRAMEWORK conform to this.
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Execution typically starts with an architecture-specific (and possibly
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CPU-specific) start.S file, such as:
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- arch/arm/cpu/armv7/start.S
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- arch/powerpc/cpu/mpc83xx/start.S
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- arch/mips/cpu/start.S
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and so on. From there, three functions are called; the purpose and
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limitations of each of these functions are described below.
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lowlevel_init():
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- purpose: essential init to permit execution to reach board_init_f()
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- no global_data or BSS
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- there is no stack (ARMv7 may have one but it will soon be removed)
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- must not set up SDRAM or use console
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- must only do the bare minimum to allow execution to continue to
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board_init_f()
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- this is almost never needed
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- return normally from this function
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board_init_f():
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- purpose: set up the machine ready for running board_init_r():
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i.e. SDRAM and serial UART
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- global_data is available
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- stack is in SRAM
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- BSS is not available, so you cannot use global/static variables,
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only stack variables and global_data
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Non-SPL-specific notes:
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- dram_init() is called to set up DRAM. If already done in SPL this
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can do nothing
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SPL-specific notes:
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- you can override the entire board_init_f() function with your own
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version as needed.
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- preloader_console_init() can be called here in extremis
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- should set up SDRAM, and anything needed to make the UART work
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- these is no need to clear BSS, it will be done by crt0.S
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- must return normally from this function (don't call board_init_r()
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directly)
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Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
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this point the stack and global_data are relocated to below
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CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
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memory.
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board_init_r():
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- purpose: main execution, common code
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- global_data is available
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- SDRAM is available
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- BSS is available, all static/global variables can be used
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- execution eventually continues to main_loop()
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Non-SPL-specific notes:
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- U-Boot is relocated to the top of memory and is now running from
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there.
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SPL-specific notes:
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- stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
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CONFIG_SPL_STACK_R_ADDR points into SDRAM
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- preloader_console_init() can be called here - typically this is
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done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
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spl_board_init() function containing this call
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- loads U-Boot or (in falcon mode) Linux
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Configuration Options:
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----------------------
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Configuration depends on the combination of board and CPU type; all
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such information is kept in a configuration file
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"include/configs/<board_name>.h".
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Example: For a TQM823L module, all configuration settings are in
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"include/configs/TQM823L.h".
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Many of the options are named exactly as the corresponding Linux
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kernel configuration options. The intention is to make it easier to
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build a config tool - later.
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The following options need to be configured:
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- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
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- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
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- Marvell Family Member
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CONFIG_SYS_MVFS - define it if you want to enable
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multiple fs option at one time
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for marvell soc family
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- 85xx CPU Options:
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CONFIG_SYS_PPC64
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Specifies that the core is a 64-bit PowerPC implementation (implements
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the "64" category of the Power ISA). This is necessary for ePAPR
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compliance, among other possible reasons.
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CONFIG_SYS_FSL_TBCLK_DIV
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Defines the core time base clock divider ratio compared to the
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system clock. On most PQ3 devices this is 8, on newer QorIQ
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devices it can be 16 or 32. The ratio varies from SoC to Soc.
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CONFIG_SYS_FSL_PCIE_COMPAT
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Defines the string to utilize when trying to match PCIe device
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tree nodes for the given platform.
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CONFIG_SYS_FSL_ERRATUM_A004510
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Enables a workaround for erratum A004510. If set,
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then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
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CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
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CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
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CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
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Defines one or two SoC revisions (low 8 bits of SVR)
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for which the A004510 workaround should be applied.
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The rest of SVR is either not relevant to the decision
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of whether the erratum is present (e.g. p2040 versus
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p2041) or is implied by the build target, which controls
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whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
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See Freescale App Note 4493 for more information about
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this erratum.
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CONFIG_A003399_NOR_WORKAROUND
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Enables a workaround for IFC erratum A003399. It is only
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required during NOR boot.
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CONFIG_A008044_WORKAROUND
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Enables a workaround for T1040/T1042 erratum A008044. It is only
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required during NAND boot and valid for Rev 1.0 SoC revision
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CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
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This is the value to write into CCSR offset 0x18600
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according to the A004510 workaround.
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CONFIG_SYS_FSL_DSP_DDR_ADDR
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This value denotes start offset of DDR memory which is
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connected exclusively to the DSP cores.
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CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
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This value denotes start offset of M2 memory
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which is directly connected to the DSP core.
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CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
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This value denotes start offset of M3 memory which is directly
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connected to the DSP core.
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CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
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This value denotes start offset of DSP CCSR space.
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CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
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Single Source Clock is clocking mode present in some of FSL SoC's.
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In this mode, a single differential clock is used to supply
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clocks to the sysclock, ddrclock and usbclock.
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CONFIG_SYS_CPC_REINIT_F
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This CONFIG is defined when the CPC is configured as SRAM at the
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time of U-Boot entry and is required to be re-initialized.
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CONFIG_DEEP_SLEEP
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Indicates this SoC supports deep sleep feature. If deep sleep is
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supported, core will start to execute uboot when wakes up.
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- Generic CPU options:
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CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
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Defines the endianess of the CPU. Implementation of those
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values is arch specific.
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CONFIG_SYS_FSL_DDR
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Freescale DDR driver in use. This type of DDR controller is
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found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
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SoCs.
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CONFIG_SYS_FSL_DDR_ADDR
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Freescale DDR memory-mapped register base.
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CONFIG_SYS_FSL_DDR_EMU
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Specify emulator support for DDR. Some DDR features such as
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deskew training are not available.
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CONFIG_SYS_FSL_DDRC_GEN1
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Freescale DDR1 controller.
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CONFIG_SYS_FSL_DDRC_GEN2
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Freescale DDR2 controller.
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CONFIG_SYS_FSL_DDRC_GEN3
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Freescale DDR3 controller.
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CONFIG_SYS_FSL_DDRC_GEN4
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Freescale DDR4 controller.
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CONFIG_SYS_FSL_DDRC_ARM_GEN3
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Freescale DDR3 controller for ARM-based SoCs.
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CONFIG_SYS_FSL_DDR1
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Board config to use DDR1. It can be enabled for SoCs with
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Freescale DDR1 or DDR2 controllers, depending on the board
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implemetation.
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CONFIG_SYS_FSL_DDR2
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Board config to use DDR2. It can be enabled for SoCs with
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Freescale DDR2 or DDR3 controllers, depending on the board
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implementation.
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CONFIG_SYS_FSL_DDR3
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Board config to use DDR3. It can be enabled for SoCs with
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Freescale DDR3 or DDR3L controllers.
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CONFIG_SYS_FSL_DDR3L
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Board config to use DDR3L. It can be enabled for SoCs with
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DDR3L controllers.
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CONFIG_SYS_FSL_DDR4
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Board config to use DDR4. It can be enabled for SoCs with
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DDR4 controllers.
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CONFIG_SYS_FSL_IFC_BE
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Defines the IFC controller register space as Big Endian
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CONFIG_SYS_FSL_IFC_LE
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Defines the IFC controller register space as Little Endian
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CONFIG_SYS_FSL_IFC_CLK_DIV
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Defines divider of platform clock(clock input to IFC controller).
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CONFIG_SYS_FSL_LBC_CLK_DIV
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Defines divider of platform clock(clock input to eLBC controller).
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CONFIG_SYS_FSL_PBL_PBI
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It enables addition of RCW (Power on reset configuration) in built image.
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Please refer doc/README.pblimage for more details
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CONFIG_SYS_FSL_PBL_RCW
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It adds PBI(pre-boot instructions) commands in u-boot build image.
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PBI commands can be used to configure SoC before it starts the execution.
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Please refer doc/README.pblimage for more details
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CONFIG_SPL_FSL_PBL
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It adds a target to create boot binary having SPL binary in PBI format
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concatenated with u-boot binary.
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CONFIG_SYS_FSL_DDR_BE
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Defines the DDR controller register space as Big Endian
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CONFIG_SYS_FSL_DDR_LE
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Defines the DDR controller register space as Little Endian
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CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
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Physical address from the view of DDR controllers. It is the
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same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
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it could be different for ARM SoCs.
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CONFIG_SYS_FSL_DDR_INTLV_256B
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DDR controller interleaving on 256-byte. This is a special
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interleaving mode, handled by Dickens for Freescale layerscape
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SoCs with ARM core.
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CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
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Number of controllers used as main memory.
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CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
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Number of controllers used for other than main memory.
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CONFIG_SYS_FSL_HAS_DP_DDR
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Defines the SoC has DP-DDR used for DPAA.
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CONFIG_SYS_FSL_SEC_BE
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Defines the SEC controller register space as Big Endian
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CONFIG_SYS_FSL_SEC_LE
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Defines the SEC controller register space as Little Endian
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- MIPS CPU options:
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CONFIG_SYS_INIT_SP_OFFSET
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Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
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pointer. This is needed for the temporary stack before
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relocation.
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CONFIG_SYS_MIPS_CACHE_MODE
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Cache operation mode for the MIPS CPU.
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See also arch/mips/include/asm/mipsregs.h.
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Possible values are:
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CONF_CM_CACHABLE_NO_WA
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CONF_CM_CACHABLE_WA
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CONF_CM_UNCACHED
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CONF_CM_CACHABLE_NONCOHERENT
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CONF_CM_CACHABLE_CE
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CONF_CM_CACHABLE_COW
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CONF_CM_CACHABLE_CUW
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CONF_CM_CACHABLE_ACCELERATED
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CONFIG_SYS_XWAY_EBU_BOOTCFG
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Special option for Lantiq XWAY SoCs for booting from NOR flash.
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See also arch/mips/cpu/mips32/start.S.
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CONFIG_XWAY_SWAP_BYTES
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Enable compilation of tools/xway-swap-bytes needed for Lantiq
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XWAY SoCs for booting from NOR flash. The U-Boot image needs to
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be swapped if a flash programmer is used.
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- ARM options:
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CONFIG_SYS_EXCEPTION_VECTORS_HIGH
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Select high exception vectors of the ARM core, e.g., do not
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clear the V bit of the c1 register of CP15.
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COUNTER_FREQUENCY
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Generic timer clock source frequency.
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COUNTER_FREQUENCY_REAL
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Generic timer clock source frequency if the real clock is
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different from COUNTER_FREQUENCY, and can only be determined
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at run time.
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- Tegra SoC options:
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CONFIG_TEGRA_SUPPORT_NON_SECURE
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Support executing U-Boot in non-secure (NS) mode. Certain
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impossible actions will be skipped if the CPU is in NS mode,
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such as ARM architectural timer initialization.
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- Linux Kernel Interface:
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CONFIG_CLOCKS_IN_MHZ
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U-Boot stores all clock information in Hz
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internally. For binary compatibility with older Linux
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kernels (which expect the clocks passed in the
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bd_info data to be in MHz) the environment variable
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"clocks_in_mhz" can be defined so that U-Boot
|
converts clock data to MHZ before passing it to the
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Linux kernel.
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When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
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"clocks_in_mhz=1" is automatically included in the
|
default environment.
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CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
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When transferring memsize parameter to Linux, some versions
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expect it to be in bytes, others in MB.
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Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
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CONFIG_OF_LIBFDT
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New kernel versions are expecting firmware settings to be
|
passed using flattened device trees (based on open firmware
|
concepts).
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CONFIG_OF_LIBFDT
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* New libfdt-based support
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* Adds the "fdt" command
|
* The bootm command automatically updates the fdt
|
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OF_TBCLK - The timebase frequency.
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OF_STDOUT_PATH - The path to the console device
|
|
boards with QUICC Engines require OF_QE to set UCC MAC
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addresses
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CONFIG_OF_BOARD_SETUP
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Board code has addition modification that it wants to make
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to the flat device tree before handing it off to the kernel
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CONFIG_OF_SYSTEM_SETUP
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Other code has addition modification that it wants to make
|
to the flat device tree before handing it off to the kernel.
|
This causes ft_system_setup() to be called before booting
|
the kernel.
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CONFIG_OF_IDE_FIXUP
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|
U-Boot can detect if an IDE device is present or not.
|
If not, and this new config option is activated, U-Boot
|
removes the ATA node from the DTS before booting Linux,
|
so the Linux IDE driver does not probe the device and
|
crash. This is needed for buggy hardware (uc101) where
|
no pull down resistor is connected to the signal IDE5V_DD7.
|
|
CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
|
|
This setting is mandatory for all boards that have only one
|
machine type and must be used to specify the machine type
|
number as it appears in the ARM machine registry
|
(see http://www.arm.linux.org.uk/developer/machines/).
|
Only boards that have multiple machine types supported
|
in a single configuration file and the machine type is
|
runtime discoverable, do not have to use this setting.
|
|
- vxWorks boot parameters:
|
|
bootvx constructs a valid bootline using the following
|
environments variables: bootdev, bootfile, ipaddr, netmask,
|
serverip, gatewayip, hostname, othbootargs.
|
It loads the vxWorks image pointed bootfile.
|
|
Note: If a "bootargs" environment is defined, it will overwride
|
the defaults discussed just above.
|
|
- Cache Configuration:
|
CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
|
CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
|
CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
|
|
- Cache Configuration for ARM:
|
CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
|
controller
|
CONFIG_SYS_PL310_BASE - Physical base address of PL310
|
controller register space
|
|
- Serial Ports:
|
CONFIG_PL010_SERIAL
|
|
Define this if you want support for Amba PrimeCell PL010 UARTs.
|
|
CONFIG_PL011_SERIAL
|
|
Define this if you want support for Amba PrimeCell PL011 UARTs.
|
|
CONFIG_PL011_CLOCK
|
|
If you have Amba PrimeCell PL011 UARTs, set this variable to
|
the clock speed of the UARTs.
|
|
CONFIG_PL01x_PORTS
|
|
If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
|
define this to a list of base addresses for each (supported)
|
port. See e.g. include/configs/versatile.h
|
|
CONFIG_SERIAL_HW_FLOW_CONTROL
|
|
Define this variable to enable hw flow control in serial driver.
|
Current user of this option is drivers/serial/nsl16550.c driver
|
|
- Console Baudrate:
|
CONFIG_BAUDRATE - in bps
|
Select one of the baudrates listed in
|
CONFIG_SYS_BAUDRATE_TABLE, see below.
|
|
- Autoboot Command:
|
CONFIG_BOOTCOMMAND
|
Only needed when CONFIG_BOOTDELAY is enabled;
|
define a command string that is automatically executed
|
when no character is read on the console interface
|
within "Boot Delay" after reset.
|
|
CONFIG_RAMBOOT and CONFIG_NFSBOOT
|
The value of these goes into the environment as
|
"ramboot" and "nfsboot" respectively, and can be used
|
as a convenience, when switching between booting from
|
RAM and NFS.
|
|
- Bootcount:
|
CONFIG_BOOTCOUNT_LIMIT
|
Implements a mechanism for detecting a repeating reboot
|
cycle, see:
|
http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
|
|
CONFIG_BOOTCOUNT_ENV
|
If no softreset save registers are found on the hardware
|
"bootcount" is stored in the environment. To prevent a
|
saveenv on all reboots, the environment variable
|
"upgrade_available" is used. If "upgrade_available" is
|
0, "bootcount" is always 0, if "upgrade_available" is
|
1 "bootcount" is incremented in the environment.
|
So the Userspace Applikation must set the "upgrade_available"
|
and "bootcount" variable to 0, if a boot was successfully.
|
|
- Pre-Boot Commands:
|
CONFIG_PREBOOT
|
|
When this option is #defined, the existence of the
|
environment variable "preboot" will be checked
|
immediately before starting the CONFIG_BOOTDELAY
|
countdown and/or running the auto-boot command resp.
|
entering interactive mode.
|
|
This feature is especially useful when "preboot" is
|
automatically generated or modified. For an example
|
see the LWMON board specific code: here "preboot" is
|
modified when the user holds down a certain
|
combination of keys on the (special) keyboard when
|
booting the systems
|
|
- Serial Download Echo Mode:
|
CONFIG_LOADS_ECHO
|
If defined to 1, all characters received during a
|
serial download (using the "loads" command) are
|
echoed back. This might be needed by some terminal
|
emulations (like "cu"), but may as well just take
|
time on others. This setting #define's the initial
|
value of the "loads_echo" environment variable.
|
|
- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
|
CONFIG_KGDB_BAUDRATE
|
Select one of the baudrates listed in
|
CONFIG_SYS_BAUDRATE_TABLE, see below.
|
|
- Removal of commands
|
If no commands are needed to boot, you can disable
|
CONFIG_CMDLINE to remove them. In this case, the command line
|
will not be available, and when U-Boot wants to execute the
|
boot command (on start-up) it will call board_run_command()
|
instead. This can reduce image size significantly for very
|
simple boot procedures.
|
|
- Regular expression support:
|
CONFIG_REGEX
|
If this variable is defined, U-Boot is linked against
|
the SLRE (Super Light Regular Expression) library,
|
which adds regex support to some commands, as for
|
example "env grep" and "setexpr".
|
|
- Device tree:
|
CONFIG_OF_CONTROL
|
If this variable is defined, U-Boot will use a device tree
|
to configure its devices, instead of relying on statically
|
compiled #defines in the board file. This option is
|
experimental and only available on a few boards. The device
|
tree is available in the global data as gd->fdt_blob.
|
|
U-Boot needs to get its device tree from somewhere. This can
|
be done using one of the three options below:
|
|
CONFIG_OF_EMBED
|
If this variable is defined, U-Boot will embed a device tree
|
binary in its image. This device tree file should be in the
|
board directory and called <soc>-<board>.dts. The binary file
|
is then picked up in board_init_f() and made available through
|
the global data structure as gd->fdt_blob.
|
|
CONFIG_OF_SEPARATE
|
If this variable is defined, U-Boot will build a device tree
|
binary. It will be called u-boot.dtb. Architecture-specific
|
code will locate it at run-time. Generally this works by:
|
|
cat u-boot.bin u-boot.dtb >image.bin
|
|
and in fact, U-Boot does this for you, creating a file called
|
u-boot-dtb.bin which is useful in the common case. You can
|
still use the individual files if you need something more
|
exotic.
|
|
CONFIG_OF_BOARD
|
If this variable is defined, U-Boot will use the device tree
|
provided by the board at runtime instead of embedding one with
|
the image. Only boards defining board_fdt_blob_setup() support
|
this option (see include/fdtdec.h file).
|
|
- Watchdog:
|
CONFIG_WATCHDOG
|
If this variable is defined, it enables watchdog
|
support for the SoC. There must be support in the SoC
|
specific code for a watchdog. For the 8xx
|
CPUs, the SIU Watchdog feature is enabled in the SYPCR
|
register. When supported for a specific SoC is
|
available, then no further board specific code should
|
be needed to use it.
|
|
CONFIG_HW_WATCHDOG
|
When using a watchdog circuitry external to the used
|
SoC, then define this variable and provide board
|
specific code for the "hw_watchdog_reset" function.
|
|
CONFIG_AT91_HW_WDT_TIMEOUT
|
specify the timeout in seconds. default 2 seconds.
|
|
- U-Boot Version:
|
CONFIG_VERSION_VARIABLE
|
If this variable is defined, an environment variable
|
named "ver" is created by U-Boot showing the U-Boot
|
version as printed by the "version" command.
|
Any change to this variable will be reverted at the
|
next reset.
|
|
- Real-Time Clock:
|
|
When CONFIG_CMD_DATE is selected, the type of the RTC
|
has to be selected, too. Define exactly one of the
|
following options:
|
|
CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
|
CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
|
CONFIG_RTC_MC146818 - use MC146818 RTC
|
CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
|
CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
|
CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
|
CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
|
CONFIG_RTC_DS164x - use Dallas DS164x RTC
|
CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
|
CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
|
CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
|
CONFIG_SYS_RV3029_TCR - enable trickle charger on
|
RV3029 RTC.
|
|
Note that if the RTC uses I2C, then the I2C interface
|
must also be configured. See I2C Support, below.
|
|
- GPIO Support:
|
CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
|
|
The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
|
chip-ngpio pairs that tell the PCA953X driver the number of
|
pins supported by a particular chip.
|
|
Note that if the GPIO device uses I2C, then the I2C interface
|
must also be configured. See I2C Support, below.
|
|
- I/O tracing:
|
When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
|
accesses and can checksum them or write a list of them out
|
to memory. See the 'iotrace' command for details. This is
|
useful for testing device drivers since it can confirm that
|
the driver behaves the same way before and after a code
|
change. Currently this is supported on sandbox and arm. To
|
add support for your architecture, add '#include <iotrace.h>'
|
to the bottom of arch/<arch>/include/asm/io.h and test.
|
|
Example output from the 'iotrace stats' command is below.
|
Note that if the trace buffer is exhausted, the checksum will
|
still continue to operate.
|
|
iotrace is enabled
|
Start: 10000000 (buffer start address)
|
Size: 00010000 (buffer size)
|
Offset: 00000120 (current buffer offset)
|
Output: 10000120 (start + offset)
|
Count: 00000018 (number of trace records)
|
CRC32: 9526fb66 (CRC32 of all trace records)
|
|
- Timestamp Support:
|
|
When CONFIG_TIMESTAMP is selected, the timestamp
|
(date and time) of an image is printed by image
|
commands like bootm or iminfo. This option is
|
automatically enabled when you select CONFIG_CMD_DATE .
|
|
- Partition Labels (disklabels) Supported:
|
Zero or more of the following:
|
CONFIG_MAC_PARTITION Apple's MacOS partition table.
|
CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
|
CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
|
bootloader. Note 2TB partition limit; see
|
disk/part_efi.c
|
CONFIG_SCSI) you must configure support for at
|
least one non-MTD partition type as well.
|
|
- IDE Reset method:
|
CONFIG_IDE_RESET_ROUTINE - this is defined in several
|
board configurations files but used nowhere!
|
|
CONFIG_IDE_RESET - is this is defined, IDE Reset will
|
be performed by calling the function
|
ide_set_reset(int reset)
|
which has to be defined in a board specific file
|
|
- ATAPI Support:
|
CONFIG_ATAPI
|
|
Set this to enable ATAPI support.
|
|
- LBA48 Support
|
CONFIG_LBA48
|
|
Set this to enable support for disks larger than 137GB
|
Also look at CONFIG_SYS_64BIT_LBA.
|
Whithout these , LBA48 support uses 32bit variables and will 'only'
|
support disks up to 2.1TB.
|
|
CONFIG_SYS_64BIT_LBA:
|
When enabled, makes the IDE subsystem use 64bit sector addresses.
|
Default is 32bit.
|
|
- SCSI Support:
|
CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
|
CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
|
CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
|
maximum numbers of LUNs, SCSI ID's and target
|
devices.
|
|
The environment variable 'scsidevs' is set to the number of
|
SCSI devices found during the last scan.
|
|
- NETWORK Support (PCI):
|
CONFIG_E1000
|
Support for Intel 8254x/8257x gigabit chips.
|
|
CONFIG_E1000_SPI
|
Utility code for direct access to the SPI bus on Intel 8257x.
|
This does not do anything useful unless you set at least one
|
of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
|
|
CONFIG_E1000_SPI_GENERIC
|
Allow generic access to the SPI bus on the Intel 8257x, for
|
example with the "sspi" command.
|
|
CONFIG_EEPRO100
|
Support for Intel 82557/82559/82559ER chips.
|
Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
|
write routine for first time initialisation.
|
|
CONFIG_TULIP
|
Support for Digital 2114x chips.
|
Optional CONFIG_TULIP_SELECT_MEDIA for board specific
|
modem chip initialisation (KS8761/QS6611).
|
|
CONFIG_NATSEMI
|
Support for National dp83815 chips.
|
|
CONFIG_NS8382X
|
Support for National dp8382[01] gigabit chips.
|
|
- NETWORK Support (other):
|
|
CONFIG_DRIVER_AT91EMAC
|
Support for AT91RM9200 EMAC.
|
|
CONFIG_RMII
|
Define this to use reduced MII inteface
|
|
CONFIG_DRIVER_AT91EMAC_QUIET
|
If this defined, the driver is quiet.
|
The driver doen't show link status messages.
|
|
CONFIG_CALXEDA_XGMAC
|
Support for the Calxeda XGMAC device
|
|
CONFIG_LAN91C96
|
Support for SMSC's LAN91C96 chips.
|
|
CONFIG_LAN91C96_USE_32_BIT
|
Define this to enable 32 bit addressing
|
|
CONFIG_SMC91111
|
Support for SMSC's LAN91C111 chip
|
|
CONFIG_SMC91111_BASE
|
Define this to hold the physical address
|
of the device (I/O space)
|
|
CONFIG_SMC_USE_32_BIT
|
Define this if data bus is 32 bits
|
|
CONFIG_SMC_USE_IOFUNCS
|
Define this to use i/o functions instead of macros
|
(some hardware wont work with macros)
|
|
CONFIG_DRIVER_TI_EMAC
|
Support for davinci emac
|
|
CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
|
Define this if you have more then 3 PHYs.
|
|
CONFIG_FTGMAC100
|
Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
|
|
CONFIG_FTGMAC100_EGIGA
|
Define this to use GE link update with gigabit PHY.
|
Define this if FTGMAC100 is connected to gigabit PHY.
|
If your system has 10/100 PHY only, it might not occur
|
wrong behavior. Because PHY usually return timeout or
|
useless data when polling gigabit status and gigabit
|
control registers. This behavior won't affect the
|
correctnessof 10/100 link speed update.
|
|
CONFIG_SMC911X
|
Support for SMSC's LAN911x and LAN921x chips
|
|
CONFIG_SMC911X_BASE
|
Define this to hold the physical address
|
of the device (I/O space)
|
|
CONFIG_SMC911X_32_BIT
|
Define this if data bus is 32 bits
|
|
CONFIG_SMC911X_16_BIT
|
Define this if data bus is 16 bits. If your processor
|
automatically converts one 32 bit word to two 16 bit
|
words you may also try CONFIG_SMC911X_32_BIT.
|
|
CONFIG_SH_ETHER
|
Support for Renesas on-chip Ethernet controller
|
|
CONFIG_SH_ETHER_USE_PORT
|
Define the number of ports to be used
|
|
CONFIG_SH_ETHER_PHY_ADDR
|
Define the ETH PHY's address
|
|
CONFIG_SH_ETHER_CACHE_WRITEBACK
|
If this option is set, the driver enables cache flush.
|
|
- PWM Support:
|
CONFIG_PWM_IMX
|
Support for PWM module on the imx6.
|
|
- TPM Support:
|
CONFIG_TPM
|
Support TPM devices.
|
|
CONFIG_TPM_TIS_INFINEON
|
Support for Infineon i2c bus TPM devices. Only one device
|
per system is supported at this time.
|
|
CONFIG_TPM_TIS_I2C_BURST_LIMITATION
|
Define the burst count bytes upper limit
|
|
CONFIG_TPM_ST33ZP24
|
Support for STMicroelectronics TPM devices. Requires DM_TPM support.
|
|
CONFIG_TPM_ST33ZP24_I2C
|
Support for STMicroelectronics ST33ZP24 I2C devices.
|
Requires TPM_ST33ZP24 and I2C.
|
|
CONFIG_TPM_ST33ZP24_SPI
|
Support for STMicroelectronics ST33ZP24 SPI devices.
|
Requires TPM_ST33ZP24 and SPI.
|
|
CONFIG_TPM_ATMEL_TWI
|
Support for Atmel TWI TPM device. Requires I2C support.
|
|
CONFIG_TPM_TIS_LPC
|
Support for generic parallel port TPM devices. Only one device
|
per system is supported at this time.
|
|
CONFIG_TPM_TIS_BASE_ADDRESS
|
Base address where the generic TPM device is mapped
|
to. Contemporary x86 systems usually map it at
|
0xfed40000.
|
|
CONFIG_TPM
|
Define this to enable the TPM support library which provides
|
functional interfaces to some TPM commands.
|
Requires support for a TPM device.
|
|
CONFIG_TPM_AUTH_SESSIONS
|
Define this to enable authorized functions in the TPM library.
|
Requires CONFIG_TPM and CONFIG_SHA1.
|
|
- USB Support:
|
At the moment only the UHCI host controller is
|
supported (PIP405, MIP405); define
|
CONFIG_USB_UHCI to enable it.
|
define CONFIG_USB_KEYBOARD to enable the USB Keyboard
|
and define CONFIG_USB_STORAGE to enable the USB
|
storage devices.
|
Note:
|
Supported are USB Keyboards and USB Floppy drives
|
(TEAC FD-05PUB).
|
|
CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
|
txfilltuning field in the EHCI controller on reset.
|
|
CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
|
HW module registers.
|
|
- USB Device:
|
Define the below if you wish to use the USB console.
|
Once firmware is rebuilt from a serial console issue the
|
command "setenv stdin usbtty; setenv stdout usbtty" and
|
attach your USB cable. The Unix command "dmesg" should print
|
it has found a new device. The environment variable usbtty
|
can be set to gserial or cdc_acm to enable your device to
|
appear to a USB host as a Linux gserial device or a
|
Common Device Class Abstract Control Model serial device.
|
If you select usbtty = gserial you should be able to enumerate
|
a Linux host by
|
# modprobe usbserial vendor=0xVendorID product=0xProductID
|
else if using cdc_acm, simply setting the environment
|
variable usbtty to be cdc_acm should suffice. The following
|
might be defined in YourBoardName.h
|
|
CONFIG_USB_DEVICE
|
Define this to build a UDC device
|
|
CONFIG_USB_TTY
|
Define this to have a tty type of device available to
|
talk to the UDC device
|
|
CONFIG_USBD_HS
|
Define this to enable the high speed support for usb
|
device and usbtty. If this feature is enabled, a routine
|
int is_usbd_high_speed(void)
|
also needs to be defined by the driver to dynamically poll
|
whether the enumeration has succeded at high speed or full
|
speed.
|
|
CONFIG_SYS_CONSOLE_IS_IN_ENV
|
Define this if you want stdin, stdout &/or stderr to
|
be set to usbtty.
|
|
If you have a USB-IF assigned VendorID then you may wish to
|
define your own vendor specific values either in BoardName.h
|
or directly in usbd_vendor_info.h. If you don't define
|
CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
|
CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
|
should pretend to be a Linux device to it's target host.
|
|
CONFIG_USBD_MANUFACTURER
|
Define this string as the name of your company for
|
- CONFIG_USBD_MANUFACTURER "my company"
|
|
CONFIG_USBD_PRODUCT_NAME
|
Define this string as the name of your product
|
- CONFIG_USBD_PRODUCT_NAME "acme usb device"
|
|
CONFIG_USBD_VENDORID
|
Define this as your assigned Vendor ID from the USB
|
Implementors Forum. This *must* be a genuine Vendor ID
|
to avoid polluting the USB namespace.
|
- CONFIG_USBD_VENDORID 0xFFFF
|
|
CONFIG_USBD_PRODUCTID
|
Define this as the unique Product ID
|
for your device
|
- CONFIG_USBD_PRODUCTID 0xFFFF
|
|
- ULPI Layer Support:
|
The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
|
the generic ULPI layer. The generic layer accesses the ULPI PHY
|
via the platform viewport, so you need both the genric layer and
|
the viewport enabled. Currently only Chipidea/ARC based
|
viewport is supported.
|
To enable the ULPI layer support, define CONFIG_USB_ULPI and
|
CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
|
If your ULPI phy needs a different reference clock than the
|
standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
|
the appropriate value in Hz.
|
|
- MMC Support:
|
The MMC controller on the Intel PXA is supported. To
|
enable this define CONFIG_MMC. The MMC can be
|
accessed from the boot prompt by mapping the device
|
to physical memory similar to flash. Command line is
|
enabled with CONFIG_CMD_MMC. The MMC driver also works with
|
the FAT fs. This is enabled with CONFIG_CMD_FAT.
|
|
CONFIG_SH_MMCIF
|
Support for Renesas on-chip MMCIF controller
|
|
CONFIG_SH_MMCIF_ADDR
|
Define the base address of MMCIF registers
|
|
CONFIG_SH_MMCIF_CLK
|
Define the clock frequency for MMCIF
|
|
CONFIG_SUPPORT_EMMC_BOOT
|
Enable some additional features of the eMMC boot partitions.
|
|
CONFIG_SUPPORT_EMMC_RPMB
|
Enable the commands for reading, writing and programming the
|
key for the Replay Protection Memory Block partition in eMMC.
|
|
- USB Device Firmware Update (DFU) class support:
|
CONFIG_USB_FUNCTION_DFU
|
This enables the USB portion of the DFU USB class
|
|
CONFIG_DFU_MMC
|
This enables support for exposing (e)MMC devices via DFU.
|
|
CONFIG_DFU_NAND
|
This enables support for exposing NAND devices via DFU.
|
|
CONFIG_DFU_RAM
|
This enables support for exposing RAM via DFU.
|
Note: DFU spec refer to non-volatile memory usage, but
|
allow usages beyond the scope of spec - here RAM usage,
|
one that would help mostly the developer.
|
|
CONFIG_SYS_DFU_DATA_BUF_SIZE
|
Dfu transfer uses a buffer before writing data to the
|
raw storage device. Make the size (in bytes) of this buffer
|
configurable. The size of this buffer is also configurable
|
through the "dfu_bufsiz" environment variable.
|
|
CONFIG_SYS_DFU_MAX_FILE_SIZE
|
When updating files rather than the raw storage device,
|
we use a static buffer to copy the file into and then write
|
the buffer once we've been given the whole file. Define
|
this to the maximum filesize (in bytes) for the buffer.
|
Default is 4 MiB if undefined.
|
|
DFU_DEFAULT_POLL_TIMEOUT
|
Poll timeout [ms], is the timeout a device can send to the
|
host. The host must wait for this timeout before sending
|
a subsequent DFU_GET_STATUS request to the device.
|
|
DFU_MANIFEST_POLL_TIMEOUT
|
Poll timeout [ms], which the device sends to the host when
|
entering dfuMANIFEST state. Host waits this timeout, before
|
sending again an USB request to the device.
|
|
- Android Bootloader support:
|
CONFIG_CMD_BOOT_ANDROID
|
This enables the command "boot_android" which executes the
|
Android Bootloader flow. Enabling CONFIG_CMD_FASTBOOT is
|
recommended to support the Android Fastboot protocol as part
|
of the bootloader.
|
|
CONFIG_ANDROID_BOOTLOADER
|
This enables support for the Android bootloader flow. Android
|
devices can boot in normal mode, recovery mode or bootloader
|
mode. The normal mode is the most common boot mode, but
|
recovery mode is often used to perform factory reset and OTA
|
(over-the-air) updates in the legacy updater. Also it is
|
possible for an Android system to request a reboot to the
|
"bootloader", which often means reboot to fastboot but may also
|
include a UI with a menu.
|
|
CONFIG_ANDROID_BOOT_IMAGE
|
This enables support for booting images which use the Android
|
image format header.
|
|
- USB Device Android Fastboot support:
|
CONFIG_USB_FUNCTION_FASTBOOT
|
This enables the USB part of the fastboot gadget
|
|
CONFIG_CMD_FASTBOOT
|
This enables the command "fastboot" which enables the Android
|
fastboot mode for the platform's USB device. Fastboot is a USB
|
protocol for downloading images, flashing and device control
|
used on Android devices.
|
See doc/README.android-fastboot for more information.
|
|
CONFIG_FASTBOOT_BUF_ADDR
|
The fastboot protocol requires a large memory buffer for
|
downloads. Define this to the starting RAM address to use for
|
downloaded images.
|
|
CONFIG_FASTBOOT_BUF_SIZE
|
The fastboot protocol requires a large memory buffer for
|
downloads. This buffer should be as large as possible for a
|
platform. Define this to the size available RAM for fastboot.
|
|
CONFIG_FASTBOOT_FLASH
|
The fastboot protocol includes a "flash" command for writing
|
the downloaded image to a non-volatile storage device. Define
|
this to enable the "fastboot flash" command.
|
|
CONFIG_FASTBOOT_FLASH_MMC_DEV
|
The fastboot "flash" command requires additional information
|
regarding the non-volatile storage device. Define this to
|
the eMMC device that fastboot should use to store the image.
|
|
CONFIG_FASTBOOT_GPT_NAME
|
The fastboot "flash" command supports writing the downloaded
|
image to the Protective MBR and the Primary GUID Partition
|
Table. (Additionally, this downloaded image is post-processed
|
to generate and write the Backup GUID Partition Table.)
|
This occurs when the specified "partition name" on the
|
"fastboot flash" command line matches this value.
|
The default is "gpt" if undefined.
|
|
CONFIG_FASTBOOT_MBR_NAME
|
The fastboot "flash" command supports writing the downloaded
|
image to DOS MBR.
|
This occurs when the "partition name" specified on the
|
"fastboot flash" command line matches this value.
|
If not defined the default value "mbr" is used.
|
|
- Journaling Flash filesystem support:
|
CONFIG_JFFS2_NAND
|
Define these for a default partition on a NAND device
|
|
CONFIG_SYS_JFFS2_FIRST_SECTOR,
|
CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
|
Define these for a default partition on a NOR device
|
|
- Keyboard Support:
|
See Kconfig help for available keyboard drivers.
|
|
CONFIG_KEYBOARD
|
|
Define this to enable a custom keyboard support.
|
This simply calls drv_keyboard_init() which must be
|
defined in your board-specific files. This option is deprecated
|
and is only used by novena. For new boards, use driver model
|
instead.
|
|
- Video support:
|
CONFIG_FSL_DIU_FB
|
Enable the Freescale DIU video driver. Reference boards for
|
SOCs that have a DIU should define this macro to enable DIU
|
support, and should also define these other macros:
|
|
CONFIG_SYS_DIU_ADDR
|
CONFIG_VIDEO
|
CONFIG_CFB_CONSOLE
|
CONFIG_VIDEO_SW_CURSOR
|
CONFIG_VGA_AS_SINGLE_DEVICE
|
CONFIG_VIDEO_LOGO
|
CONFIG_VIDEO_BMP_LOGO
|
|
The DIU driver will look for the 'video-mode' environment
|
variable, and if defined, enable the DIU as a console during
|
boot. See the documentation file doc/README.video for a
|
description of this variable.
|
|
- LCD Support: CONFIG_LCD
|
|
Define this to enable LCD support (for output to LCD
|
display); also select one of the supported displays
|
by defining one of these:
|
|
CONFIG_ATMEL_LCD:
|
|
HITACHI TX09D70VM1CCA, 3.5", 240x320.
|
|
CONFIG_NEC_NL6448AC33:
|
|
NEC NL6448AC33-18. Active, color, single scan.
|
|
CONFIG_NEC_NL6448BC20
|
|
NEC NL6448BC20-08. 6.5", 640x480.
|
Active, color, single scan.
|
|
CONFIG_NEC_NL6448BC33_54
|
|
NEC NL6448BC33-54. 10.4", 640x480.
|
Active, color, single scan.
|
|
CONFIG_SHARP_16x9
|
|
Sharp 320x240. Active, color, single scan.
|
It isn't 16x9, and I am not sure what it is.
|
|
CONFIG_SHARP_LQ64D341
|
|
Sharp LQ64D341 display, 640x480.
|
Active, color, single scan.
|
|
CONFIG_HLD1045
|
|
HLD1045 display, 640x480.
|
Active, color, single scan.
|
|
CONFIG_OPTREX_BW
|
|
Optrex CBL50840-2 NF-FW 99 22 M5
|
or
|
Hitachi LMG6912RPFC-00T
|
or
|
Hitachi SP14Q002
|
|
320x240. Black & white.
|
|
CONFIG_LCD_ALIGNMENT
|
|
Normally the LCD is page-aligned (typically 4KB). If this is
|
defined then the LCD will be aligned to this value instead.
|
For ARM it is sometimes useful to use MMU_SECTION_SIZE
|
here, since it is cheaper to change data cache settings on
|
a per-section basis.
|
|
|
CONFIG_LCD_ROTATION
|
|
Sometimes, for example if the display is mounted in portrait
|
mode or even if it's mounted landscape but rotated by 180degree,
|
we need to rotate our content of the display relative to the
|
framebuffer, so that user can read the messages which are
|
printed out.
|
Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
|
initialized with a given rotation from "vl_rot" out of
|
"vidinfo_t" which is provided by the board specific code.
|
The value for vl_rot is coded as following (matching to
|
fbcon=rotate:<n> linux-kernel commandline):
|
0 = no rotation respectively 0 degree
|
1 = 90 degree rotation
|
2 = 180 degree rotation
|
3 = 270 degree rotation
|
|
If CONFIG_LCD_ROTATION is not defined, the console will be
|
initialized with 0degree rotation.
|
|
CONFIG_LCD_BMP_RLE8
|
|
Support drawing of RLE8-compressed bitmaps on the LCD.
|
|
CONFIG_I2C_EDID
|
|
Enables an 'i2c edid' command which can read EDID
|
information over I2C from an attached LCD display.
|
|
- Splash Screen Support: CONFIG_SPLASH_SCREEN
|
|
If this option is set, the environment is checked for
|
a variable "splashimage". If found, the usual display
|
of logo, copyright and system information on the LCD
|
is suppressed and the BMP image at the address
|
specified in "splashimage" is loaded instead. The
|
console is redirected to the "nulldev", too. This
|
allows for a "silent" boot where a splash screen is
|
loaded very quickly after power-on.
|
|
CONFIG_SPLASHIMAGE_GUARD
|
|
If this option is set, then U-Boot will prevent the environment
|
variable "splashimage" from being set to a problematic address
|
(see doc/README.displaying-bmps).
|
This option is useful for targets where, due to alignment
|
restrictions, an improperly aligned BMP image will cause a data
|
abort. If you think you will not have problems with unaligned
|
accesses (for example because your toolchain prevents them)
|
there is no need to set this option.
|
|
CONFIG_SPLASH_SCREEN_ALIGN
|
|
If this option is set the splash image can be freely positioned
|
on the screen. Environment variable "splashpos" specifies the
|
position as "x,y". If a positive number is given it is used as
|
number of pixel from left/top. If a negative number is given it
|
is used as number of pixel from right/bottom. You can also
|
specify 'm' for centering the image.
|
|
Example:
|
setenv splashpos m,m
|
=> image at center of screen
|
|
setenv splashpos 30,20
|
=> image at x = 30 and y = 20
|
|
setenv splashpos -10,m
|
=> vertically centered image
|
at x = dspWidth - bmpWidth - 9
|
|
- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
|
|
If this option is set, additionally to standard BMP
|
images, gzipped BMP images can be displayed via the
|
splashscreen support or the bmp command.
|
|
- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
|
|
If this option is set, 8-bit RLE compressed BMP images
|
can be displayed via the splashscreen support or the
|
bmp command.
|
|
- Compression support:
|
CONFIG_GZIP
|
|
Enabled by default to support gzip compressed images.
|
|
CONFIG_BZIP2
|
|
If this option is set, support for bzip2 compressed
|
images is included. If not, only uncompressed and gzip
|
compressed images are supported.
|
|
NOTE: the bzip2 algorithm requires a lot of RAM, so
|
the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
|
be at least 4MB.
|
|
- MII/PHY support:
|
CONFIG_PHY_ADDR
|
|
The address of PHY on MII bus.
|
|
CONFIG_PHY_CLOCK_FREQ (ppc4xx)
|
|
The clock frequency of the MII bus
|
|
CONFIG_PHY_RESET_DELAY
|
|
Some PHY like Intel LXT971A need extra delay after
|
reset before any MII register access is possible.
|
For such PHY, set this option to the usec delay
|
required. (minimum 300usec for LXT971A)
|
|
CONFIG_PHY_CMD_DELAY (ppc4xx)
|
|
Some PHY like Intel LXT971A need extra delay after
|
command issued before MII status register can be read
|
|
- IP address:
|
CONFIG_IPADDR
|
|
Define a default value for the IP address to use for
|
the default Ethernet interface, in case this is not
|
determined through e.g. bootp.
|
(Environment variable "ipaddr")
|
|
- Server IP address:
|
CONFIG_SERVERIP
|
|
Defines a default value for the IP address of a TFTP
|
server to contact when using the "tftboot" command.
|
(Environment variable "serverip")
|
|
CONFIG_KEEP_SERVERADDR
|
|
Keeps the server's MAC address, in the env 'serveraddr'
|
for passing to bootargs (like Linux's netconsole option)
|
|
- Gateway IP address:
|
CONFIG_GATEWAYIP
|
|
Defines a default value for the IP address of the
|
default router where packets to other networks are
|
sent to.
|
(Environment variable "gatewayip")
|
|
- Subnet mask:
|
CONFIG_NETMASK
|
|
Defines a default value for the subnet mask (or
|
routing prefix) which is used to determine if an IP
|
address belongs to the local subnet or needs to be
|
forwarded through a router.
|
(Environment variable "netmask")
|
|
- Multicast TFTP Mode:
|
CONFIG_MCAST_TFTP
|
|
Defines whether you want to support multicast TFTP as per
|
rfc-2090; for example to work with atftp. Lets lots of targets
|
tftp down the same boot image concurrently. Note: the Ethernet
|
driver in use must provide a function: mcast() to join/leave a
|
multicast group.
|
|
- BOOTP Recovery Mode:
|
CONFIG_BOOTP_RANDOM_DELAY
|
|
If you have many targets in a network that try to
|
boot using BOOTP, you may want to avoid that all
|
systems send out BOOTP requests at precisely the same
|
moment (which would happen for instance at recovery
|
from a power failure, when all systems will try to
|
boot, thus flooding the BOOTP server. Defining
|
CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
|
inserted before sending out BOOTP requests. The
|
following delays are inserted then:
|
|
1st BOOTP request: delay 0 ... 1 sec
|
2nd BOOTP request: delay 0 ... 2 sec
|
3rd BOOTP request: delay 0 ... 4 sec
|
4th and following
|
BOOTP requests: delay 0 ... 8 sec
|
|
CONFIG_BOOTP_ID_CACHE_SIZE
|
|
BOOTP packets are uniquely identified using a 32-bit ID. The
|
server will copy the ID from client requests to responses and
|
U-Boot will use this to determine if it is the destination of
|
an incoming response. Some servers will check that addresses
|
aren't in use before handing them out (usually using an ARP
|
ping) and therefore take up to a few hundred milliseconds to
|
respond. Network congestion may also influence the time it
|
takes for a response to make it back to the client. If that
|
time is too long, U-Boot will retransmit requests. In order
|
to allow earlier responses to still be accepted after these
|
retransmissions, U-Boot's BOOTP client keeps a small cache of
|
IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
|
cache. The default is to keep IDs for up to four outstanding
|
requests. Increasing this will allow U-Boot to accept offers
|
from a BOOTP client in networks with unusually high latency.
|
|
- DHCP Advanced Options:
|
You can fine tune the DHCP functionality by defining
|
CONFIG_BOOTP_* symbols:
|
|
CONFIG_BOOTP_SUBNETMASK
|
CONFIG_BOOTP_GATEWAY
|
CONFIG_BOOTP_HOSTNAME
|
CONFIG_BOOTP_NISDOMAIN
|
CONFIG_BOOTP_BOOTPATH
|
CONFIG_BOOTP_BOOTFILESIZE
|
CONFIG_BOOTP_DNS
|
CONFIG_BOOTP_DNS2
|
CONFIG_BOOTP_SEND_HOSTNAME
|
CONFIG_BOOTP_NTPSERVER
|
CONFIG_BOOTP_TIMEOFFSET
|
CONFIG_BOOTP_VENDOREX
|
CONFIG_BOOTP_MAY_FAIL
|
|
CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
|
environment variable, not the BOOTP server.
|
|
CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
|
after the configured retry count, the call will fail
|
instead of starting over. This can be used to fail over
|
to Link-local IP address configuration if the DHCP server
|
is not available.
|
|
CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
|
serverip from a DHCP server, it is possible that more
|
than one DNS serverip is offered to the client.
|
If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
|
serverip will be stored in the additional environment
|
variable "dnsip2". The first DNS serverip is always
|
stored in the variable "dnsip", when CONFIG_BOOTP_DNS
|
is defined.
|
|
CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
|
to do a dynamic update of a DNS server. To do this, they
|
need the hostname of the DHCP requester.
|
If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
|
of the "hostname" environment variable is passed as
|
option 12 to the DHCP server.
|
|
CONFIG_BOOTP_DHCP_REQUEST_DELAY
|
|
A 32bit value in microseconds for a delay between
|
receiving a "DHCP Offer" and sending the "DHCP Request".
|
This fixes a problem with certain DHCP servers that don't
|
respond 100% of the time to a "DHCP request". E.g. On an
|
AT91RM9200 processor running at 180MHz, this delay needed
|
to be *at least* 15,000 usec before a Windows Server 2003
|
DHCP server would reply 100% of the time. I recommend at
|
least 50,000 usec to be safe. The alternative is to hope
|
that one of the retries will be successful but note that
|
the DHCP timeout and retry process takes a longer than
|
this delay.
|
|
- Link-local IP address negotiation:
|
Negotiate with other link-local clients on the local network
|
for an address that doesn't require explicit configuration.
|
This is especially useful if a DHCP server cannot be guaranteed
|
to exist in all environments that the device must operate.
|
|
See doc/README.link-local for more information.
|
|
- MAC address from environment variables
|
|
FDT_SEQ_MACADDR_FROM_ENV
|
|
Fix-up device tree with MAC addresses fetched sequentially from
|
environment variables. This config work on assumption that
|
non-usable ethernet node of device-tree are either not present
|
or their status has been marked as "disabled".
|
|
- CDP Options:
|
CONFIG_CDP_DEVICE_ID
|
|
The device id used in CDP trigger frames.
|
|
CONFIG_CDP_DEVICE_ID_PREFIX
|
|
A two character string which is prefixed to the MAC address
|
of the device.
|
|
CONFIG_CDP_PORT_ID
|
|
A printf format string which contains the ascii name of
|
the port. Normally is set to "eth%d" which sets
|
eth0 for the first Ethernet, eth1 for the second etc.
|
|
CONFIG_CDP_CAPABILITIES
|
|
A 32bit integer which indicates the device capabilities;
|
0x00000010 for a normal host which does not forwards.
|
|
CONFIG_CDP_VERSION
|
|
An ascii string containing the version of the software.
|
|
CONFIG_CDP_PLATFORM
|
|
An ascii string containing the name of the platform.
|
|
CONFIG_CDP_TRIGGER
|
|
A 32bit integer sent on the trigger.
|
|
CONFIG_CDP_POWER_CONSUMPTION
|
|
A 16bit integer containing the power consumption of the
|
device in .1 of milliwatts.
|
|
CONFIG_CDP_APPLIANCE_VLAN_TYPE
|
|
A byte containing the id of the VLAN.
|
|
- Status LED: CONFIG_LED_STATUS
|
|
Several configurations allow to display the current
|
status using a LED. For instance, the LED will blink
|
fast while running U-Boot code, stop blinking as
|
soon as a reply to a BOOTP request was received, and
|
start blinking slow once the Linux kernel is running
|
(supported by a status LED driver in the Linux
|
kernel). Defining CONFIG_LED_STATUS enables this
|
feature in U-Boot.
|
|
Additional options:
|
|
CONFIG_LED_STATUS_GPIO
|
The status LED can be connected to a GPIO pin.
|
In such cases, the gpio_led driver can be used as a
|
status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
|
to include the gpio_led driver in the U-Boot binary.
|
|
CONFIG_GPIO_LED_INVERTED_TABLE
|
Some GPIO connected LEDs may have inverted polarity in which
|
case the GPIO high value corresponds to LED off state and
|
GPIO low value corresponds to LED on state.
|
In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
|
with a list of GPIO LEDs that have inverted polarity.
|
|
- I2C Support: CONFIG_SYS_I2C
|
|
This enable the NEW i2c subsystem, and will allow you to use
|
i2c commands at the u-boot command line (as long as you set
|
CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
|
based realtime clock chips or other i2c devices. See
|
common/cmd_i2c.c for a description of the command line
|
interface.
|
|
ported i2c driver to the new framework:
|
- drivers/i2c/soft_i2c.c:
|
- activate first bus with CONFIG_SYS_I2C_SOFT define
|
CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
|
for defining speed and slave address
|
- activate second bus with I2C_SOFT_DECLARATIONS2 define
|
CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
|
for defining speed and slave address
|
- activate third bus with I2C_SOFT_DECLARATIONS3 define
|
CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
|
for defining speed and slave address
|
- activate fourth bus with I2C_SOFT_DECLARATIONS4 define
|
CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
|
for defining speed and slave address
|
|
- drivers/i2c/fsl_i2c.c:
|
- activate i2c driver with CONFIG_SYS_I2C_FSL
|
define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
|
offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
|
CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
|
bus.
|
- If your board supports a second fsl i2c bus, define
|
CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
|
CONFIG_SYS_FSL_I2C2_SPEED for the speed and
|
CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
|
second bus.
|
|
- drivers/i2c/tegra_i2c.c:
|
- activate this driver with CONFIG_SYS_I2C_TEGRA
|
- This driver adds 4 i2c buses with a fix speed from
|
100000 and the slave addr 0!
|
|
- drivers/i2c/ppc4xx_i2c.c
|
- activate this driver with CONFIG_SYS_I2C_PPC4XX
|
- CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
|
- CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
|
|
- drivers/i2c/i2c_mxc.c
|
- activate this driver with CONFIG_SYS_I2C_MXC
|
- enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
|
- enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
|
- enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
|
- enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
|
- define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
|
- define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
|
- define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
|
- define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
|
- define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
|
- define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
|
- define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
|
- define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
|
If those defines are not set, default value is 100000
|
for speed, and 0 for slave.
|
|
- drivers/i2c/rcar_i2c.c:
|
- activate this driver with CONFIG_SYS_I2C_RCAR
|
- This driver adds 4 i2c buses
|
|
- CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
|
- CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
|
- CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
|
- CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
|
- CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
|
- CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
|
- CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
|
- CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
|
- CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
|
|
- drivers/i2c/sh_i2c.c:
|
- activate this driver with CONFIG_SYS_I2C_SH
|
- This driver adds from 2 to 5 i2c buses
|
|
- CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
|
- CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
|
- CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
|
- CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
|
- CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
|
- CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
|
- CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
|
- CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
|
- CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
|
- CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
|
- CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
|
|
- drivers/i2c/omap24xx_i2c.c
|
- activate this driver with CONFIG_SYS_I2C_OMAP24XX
|
- CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
|
- CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
|
- CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
|
- CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
|
- CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
|
- CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
|
- CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
|
- CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
|
- CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
|
- CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
|
|
- drivers/i2c/zynq_i2c.c
|
- activate this driver with CONFIG_SYS_I2C_ZYNQ
|
- set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting
|
- set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr
|
|
- drivers/i2c/s3c24x0_i2c.c:
|
- activate this driver with CONFIG_SYS_I2C_S3C24X0
|
- This driver adds i2c buses (11 for Exynos5250, Exynos5420
|
9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
|
with a fix speed from 100000 and the slave addr 0!
|
|
- drivers/i2c/ihs_i2c.c
|
- activate this driver with CONFIG_SYS_I2C_IHS
|
- CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
|
- CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
|
- CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
|
- CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
|
- CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
|
- CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
|
- CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
|
- CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
|
- CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
|
- CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
|
- CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
|
- CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
|
- activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
|
- CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
|
- CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
|
- CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
|
- CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
|
- CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
|
- CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
|
- CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
|
- CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
|
|
additional defines:
|
|
CONFIG_SYS_NUM_I2C_BUSES
|
Hold the number of i2c buses you want to use.
|
|
CONFIG_SYS_I2C_DIRECT_BUS
|
define this, if you don't use i2c muxes on your hardware.
|
if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
|
omit this define.
|
|
CONFIG_SYS_I2C_MAX_HOPS
|
define how many muxes are maximal consecutively connected
|
on one i2c bus. If you not use i2c muxes, omit this
|
define.
|
|
CONFIG_SYS_I2C_BUSES
|
hold a list of buses you want to use, only used if
|
CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
|
a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
|
CONFIG_SYS_NUM_I2C_BUSES = 9:
|
|
CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
|
{0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
|
{0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
|
{0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
|
{0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
|
{0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
|
{1, {I2C_NULL_HOP}}, \
|
{1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
|
{1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
|
}
|
|
which defines
|
bus 0 on adapter 0 without a mux
|
bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
|
bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
|
bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
|
bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
|
bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
|
bus 6 on adapter 1 without a mux
|
bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
|
bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
|
|
If you do not have i2c muxes on your board, omit this define.
|
|
- Legacy I2C Support:
|
If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
|
then the following macros need to be defined (examples are
|
from include/configs/lwmon.h):
|
|
I2C_INIT
|
|
(Optional). Any commands necessary to enable the I2C
|
controller or configure ports.
|
|
eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
|
|
I2C_ACTIVE
|
|
The code necessary to make the I2C data line active
|
(driven). If the data line is open collector, this
|
define can be null.
|
|
eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
|
|
I2C_TRISTATE
|
|
The code necessary to make the I2C data line tri-stated
|
(inactive). If the data line is open collector, this
|
define can be null.
|
|
eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
|
|
I2C_READ
|
|
Code that returns true if the I2C data line is high,
|
false if it is low.
|
|
eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
|
|
I2C_SDA(bit)
|
|
If <bit> is true, sets the I2C data line high. If it
|
is false, it clears it (low).
|
|
eg: #define I2C_SDA(bit) \
|
if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
|
else immr->im_cpm.cp_pbdat &= ~PB_SDA
|
|
I2C_SCL(bit)
|
|
If <bit> is true, sets the I2C clock line high. If it
|
is false, it clears it (low).
|
|
eg: #define I2C_SCL(bit) \
|
if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
|
else immr->im_cpm.cp_pbdat &= ~PB_SCL
|
|
I2C_DELAY
|
|
This delay is invoked four times per clock cycle so this
|
controls the rate of data transfer. The data rate thus
|
is 1 / (I2C_DELAY * 4). Often defined to be something
|
like:
|
|
#define I2C_DELAY udelay(2)
|
|
CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
|
|
If your arch supports the generic GPIO framework (asm/gpio.h),
|
then you may alternatively define the two GPIOs that are to be
|
used as SCL / SDA. Any of the previous I2C_xxx macros will
|
have GPIO-based defaults assigned to them as appropriate.
|
|
You should define these to the GPIO value as given directly to
|
the generic GPIO functions.
|
|
CONFIG_SYS_I2C_INIT_BOARD
|
|
When a board is reset during an i2c bus transfer
|
chips might think that the current transfer is still
|
in progress. On some boards it is possible to access
|
the i2c SCLK line directly, either by using the
|
processor pin as a GPIO or by having a second pin
|
connected to the bus. If this option is defined a
|
custom i2c_init_board() routine in boards/xxx/board.c
|
is run early in the boot sequence.
|
|
CONFIG_I2C_MULTI_BUS
|
|
This option allows the use of multiple I2C buses, each of which
|
must have a controller. At any point in time, only one bus is
|
active. To switch to a different bus, use the 'i2c dev' command.
|
Note that bus numbering is zero-based.
|
|
CONFIG_SYS_I2C_NOPROBES
|
|
This option specifies a list of I2C devices that will be skipped
|
when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
|
is set, specify a list of bus-device pairs. Otherwise, specify
|
a 1D array of device addresses
|
|
e.g.
|
#undef CONFIG_I2C_MULTI_BUS
|
#define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
|
|
will skip addresses 0x50 and 0x68 on a board with one I2C bus
|
|
#define CONFIG_I2C_MULTI_BUS
|
#define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
|
|
will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
|
|
CONFIG_SYS_SPD_BUS_NUM
|
|
If defined, then this indicates the I2C bus number for DDR SPD.
|
If not defined, then U-Boot assumes that SPD is on I2C bus 0.
|
|
CONFIG_SYS_RTC_BUS_NUM
|
|
If defined, then this indicates the I2C bus number for the RTC.
|
If not defined, then U-Boot assumes that RTC is on I2C bus 0.
|
|
CONFIG_SOFT_I2C_READ_REPEATED_START
|
|
defining this will force the i2c_read() function in
|
the soft_i2c driver to perform an I2C repeated start
|
between writing the address pointer and reading the
|
data. If this define is omitted the default behaviour
|
of doing a stop-start sequence will be used. Most I2C
|
devices can use either method, but some require one or
|
the other.
|
|
- SPI Support: CONFIG_SPI
|
|
Enables SPI driver (so far only tested with
|
SPI EEPROM, also an instance works with Crystal A/D and
|
D/As on the SACSng board)
|
|
CONFIG_SOFT_SPI
|
|
Enables a software (bit-bang) SPI driver rather than
|
using hardware support. This is a general purpose
|
driver that only requires three general I/O port pins
|
(two outputs, one input) to function. If this is
|
defined, the board configuration must define several
|
SPI configuration items (port pins to use, etc). For
|
an example, see include/configs/sacsng.h.
|
|
CONFIG_HARD_SPI
|
|
Enables a hardware SPI driver for general-purpose reads
|
and writes. As with CONFIG_SOFT_SPI, the board configuration
|
must define a list of chip-select function pointers.
|
Currently supported on some MPC8xxx processors. For an
|
example, see include/configs/mpc8349emds.h.
|
|
CONFIG_MXC_SPI
|
|
Enables the driver for the SPI controllers on i.MX and MXC
|
SoCs. Currently i.MX31/35/51 are supported.
|
|
CONFIG_SYS_SPI_MXC_WAIT
|
Timeout for waiting until spi transfer completed.
|
default: (CONFIG_SYS_HZ/100) /* 10 ms */
|
|
- FPGA Support: CONFIG_FPGA
|
|
Enables FPGA subsystem.
|
|
CONFIG_FPGA_<vendor>
|
|
Enables support for specific chip vendors.
|
(ALTERA, XILINX)
|
|
CONFIG_FPGA_<family>
|
|
Enables support for FPGA family.
|
(SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
|
|
CONFIG_FPGA_COUNT
|
|
Specify the number of FPGA devices to support.
|
|
CONFIG_SYS_FPGA_PROG_FEEDBACK
|
|
Enable printing of hash marks during FPGA configuration.
|
|
CONFIG_SYS_FPGA_CHECK_BUSY
|
|
Enable checks on FPGA configuration interface busy
|
status by the configuration function. This option
|
will require a board or device specific function to
|
be written.
|
|
CONFIG_FPGA_DELAY
|
|
If defined, a function that provides delays in the FPGA
|
configuration driver.
|
|
CONFIG_SYS_FPGA_CHECK_CTRLC
|
Allow Control-C to interrupt FPGA configuration
|
|
CONFIG_SYS_FPGA_CHECK_ERROR
|
|
Check for configuration errors during FPGA bitfile
|
loading. For example, abort during Virtex II
|
configuration if the INIT_B line goes low (which
|
indicated a CRC error).
|
|
CONFIG_SYS_FPGA_WAIT_INIT
|
|
Maximum time to wait for the INIT_B line to de-assert
|
after PROB_B has been de-asserted during a Virtex II
|
FPGA configuration sequence. The default time is 500
|
ms.
|
|
CONFIG_SYS_FPGA_WAIT_BUSY
|
|
Maximum time to wait for BUSY to de-assert during
|
Virtex II FPGA configuration. The default is 5 ms.
|
|
CONFIG_SYS_FPGA_WAIT_CONFIG
|
|
Time to wait after FPGA configuration. The default is
|
200 ms.
|
|
- Configuration Management:
|
CONFIG_BUILD_TARGET
|
|
Some SoCs need special image types (e.g. U-Boot binary
|
with a special header) as build targets. By defining
|
CONFIG_BUILD_TARGET in the SoC / board header, this
|
special image will be automatically built upon calling
|
make / buildman.
|
|
CONFIG_IDENT_STRING
|
|
If defined, this string will be added to the U-Boot
|
version information (U_BOOT_VERSION)
|
|
- Vendor Parameter Protection:
|
|
U-Boot considers the values of the environment
|
variables "serial#" (Board Serial Number) and
|
"ethaddr" (Ethernet Address) to be parameters that
|
are set once by the board vendor / manufacturer, and
|
protects these variables from casual modification by
|
the user. Once set, these variables are read-only,
|
and write or delete attempts are rejected. You can
|
change this behaviour:
|
|
If CONFIG_ENV_OVERWRITE is #defined in your config
|
file, the write protection for vendor parameters is
|
completely disabled. Anybody can change or delete
|
these parameters.
|
|
Alternatively, if you define _both_ an ethaddr in the
|
default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
|
Ethernet address is installed in the environment,
|
which can be changed exactly ONCE by the user. [The
|
serial# is unaffected by this, i. e. it remains
|
read-only.]
|
|
The same can be accomplished in a more flexible way
|
for any variable by configuring the type of access
|
to allow for those variables in the ".flags" variable
|
or define CONFIG_ENV_FLAGS_LIST_STATIC.
|
|
- Protected RAM:
|
CONFIG_PRAM
|
|
Define this variable to enable the reservation of
|
"protected RAM", i. e. RAM which is not overwritten
|
by U-Boot. Define CONFIG_PRAM to hold the number of
|
kB you want to reserve for pRAM. You can overwrite
|
this default value by defining an environment
|
variable "pram" to the number of kB you want to
|
reserve. Note that the board info structure will
|
still show the full amount of RAM. If pRAM is
|
reserved, a new environment variable "mem" will
|
automatically be defined to hold the amount of
|
remaining RAM in a form that can be passed as boot
|
argument to Linux, for instance like that:
|
|
setenv bootargs ... mem=\${mem}
|
saveenv
|
|
This way you can tell Linux not to use this memory,
|
either, which results in a memory region that will
|
not be affected by reboots.
|
|
*WARNING* If your board configuration uses automatic
|
detection of the RAM size, you must make sure that
|
this memory test is non-destructive. So far, the
|
following board configurations are known to be
|
"pRAM-clean":
|
|
IVMS8, IVML24, SPD8xx,
|
HERMES, IP860, RPXlite, LWMON,
|
FLAGADM
|
|
- Access to physical memory region (> 4GB)
|
Some basic support is provided for operations on memory not
|
normally accessible to U-Boot - e.g. some architectures
|
support access to more than 4GB of memory on 32-bit
|
machines using physical address extension or similar.
|
Define CONFIG_PHYSMEM to access this basic support, which
|
currently only supports clearing the memory.
|
|
- Error Recovery:
|
CONFIG_NET_RETRY_COUNT
|
|
This variable defines the number of retries for
|
network operations like ARP, RARP, TFTP, or BOOTP
|
before giving up the operation. If not defined, a
|
default value of 5 is used.
|
|
CONFIG_ARP_TIMEOUT
|
|
Timeout waiting for an ARP reply in milliseconds.
|
|
CONFIG_NFS_TIMEOUT
|
|
Timeout in milliseconds used in NFS protocol.
|
If you encounter "ERROR: Cannot umount" in nfs command,
|
try longer timeout such as
|
#define CONFIG_NFS_TIMEOUT 10000UL
|
|
- Command Interpreter:
|
CONFIG_AUTO_COMPLETE
|
|
Enable auto completion of commands using TAB.
|
|
CONFIG_SYS_PROMPT_HUSH_PS2
|
|
This defines the secondary prompt string, which is
|
printed when the command interpreter needs more input
|
to complete a command. Usually "> ".
|
|
Note:
|
|
In the current implementation, the local variables
|
space and global environment variables space are
|
separated. Local variables are those you define by
|
simply typing `name=value'. To access a local
|
variable later on, you have write `$name' or
|
`${name}'; to execute the contents of a variable
|
directly type `$name' at the command prompt.
|
|
Global environment variables are those you use
|
setenv/printenv to work with. To run a command stored
|
in such a variable, you need to use the run command,
|
and you must not use the '$' sign to access them.
|
|
To store commands and special characters in a
|
variable, please use double quotation marks
|
surrounding the whole text of the variable, instead
|
of the backslashes before semicolons and special
|
symbols.
|
|
- Command Line Editing and History:
|
CONFIG_CMDLINE_EDITING
|
|
Enable editing and History functions for interactive
|
command line input operations
|
|
- Command Line PS1/PS2 support:
|
CONFIG_CMDLINE_PS_SUPPORT
|
|
Enable support for changing the command prompt string
|
at run-time. Only static string is supported so far.
|
The string is obtained from environment variables PS1
|
and PS2.
|
|
- Default Environment:
|
CONFIG_EXTRA_ENV_SETTINGS
|
|
Define this to contain any number of null terminated
|
strings (variable = value pairs) that will be part of
|
the default environment compiled into the boot image.
|
|
For example, place something like this in your
|
board's config file:
|
|
#define CONFIG_EXTRA_ENV_SETTINGS \
|
"myvar1=value1\0" \
|
"myvar2=value2\0"
|
|
Warning: This method is based on knowledge about the
|
internal format how the environment is stored by the
|
U-Boot code. This is NOT an official, exported
|
interface! Although it is unlikely that this format
|
will change soon, there is no guarantee either.
|
You better know what you are doing here.
|
|
Note: overly (ab)use of the default environment is
|
discouraged. Make sure to check other ways to preset
|
the environment like the "source" command or the
|
boot command first.
|
|
CONFIG_ENV_VARS_UBOOT_CONFIG
|
|
Define this in order to add variables describing the
|
U-Boot build configuration to the default environment.
|
These will be named arch, cpu, board, vendor, and soc.
|
|
Enabling this option will cause the following to be defined:
|
|
- CONFIG_SYS_ARCH
|
- CONFIG_SYS_CPU
|
- CONFIG_SYS_BOARD
|
- CONFIG_SYS_VENDOR
|
- CONFIG_SYS_SOC
|
|
CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
|
|
Define this in order to add variables describing certain
|
run-time determined information about the hardware to the
|
environment. These will be named board_name, board_rev.
|
|
CONFIG_DELAY_ENVIRONMENT
|
|
Normally the environment is loaded when the board is
|
initialised so that it is available to U-Boot. This inhibits
|
that so that the environment is not available until
|
explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
|
this is instead controlled by the value of
|
/config/load-environment.
|
|
- TFTP Fixed UDP Port:
|
CONFIG_TFTP_PORT
|
|
If this is defined, the environment variable tftpsrcp
|
is used to supply the TFTP UDP source port value.
|
If tftpsrcp isn't defined, the normal pseudo-random port
|
number generator is used.
|
|
Also, the environment variable tftpdstp is used to supply
|
the TFTP UDP destination port value. If tftpdstp isn't
|
defined, the normal port 69 is used.
|
|
The purpose for tftpsrcp is to allow a TFTP server to
|
blindly start the TFTP transfer using the pre-configured
|
target IP address and UDP port. This has the effect of
|
"punching through" the (Windows XP) firewall, allowing
|
the remainder of the TFTP transfer to proceed normally.
|
A better solution is to properly configure the firewall,
|
but sometimes that is not allowed.
|
|
- bootcount support:
|
CONFIG_BOOTCOUNT_LIMIT
|
|
This enables the bootcounter support, see:
|
http://www.denx.de/wiki/DULG/UBootBootCountLimit
|
|
CONFIG_AT91SAM9XE
|
enable special bootcounter support on at91sam9xe based boards.
|
CONFIG_SOC_DA8XX
|
enable special bootcounter support on da850 based boards.
|
CONFIG_BOOTCOUNT_RAM
|
enable support for the bootcounter in RAM
|
CONFIG_BOOTCOUNT_I2C
|
enable support for the bootcounter on an i2c (like RTC) device.
|
CONFIG_SYS_I2C_RTC_ADDR = i2c chip address
|
CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for
|
the bootcounter.
|
CONFIG_BOOTCOUNT_ALEN = address len
|
CONFIG_BOOTCOUNT_EXT
|
enable support for the bootcounter in EXT filesystem
|
CONFIG_SYS_BOOTCOUNT_ADDR = RAM address used for read
|
and write.
|
CONFIG_SYS_BOOTCOUNT_EXT_INTERFACE = interface
|
CONFIG_SYS_BOOTCOUNT_EXT_DEVPART = device and part
|
CONFIG_SYS_BOOTCOUNT_EXT_NAME = filename
|
|
- Show boot progress:
|
CONFIG_SHOW_BOOT_PROGRESS
|
|
Defining this option allows to add some board-
|
specific code (calling a user-provided function
|
"show_boot_progress(int)") that enables you to show
|
the system's boot progress on some display (for
|
example, some LED's) on your board. At the moment,
|
the following checkpoints are implemented:
|
|
|
Legacy uImage format:
|
|
Arg Where When
|
1 common/cmd_bootm.c before attempting to boot an image
|
-1 common/cmd_bootm.c Image header has bad magic number
|
2 common/cmd_bootm.c Image header has correct magic number
|
-2 common/cmd_bootm.c Image header has bad checksum
|
3 common/cmd_bootm.c Image header has correct checksum
|
-3 common/cmd_bootm.c Image data has bad checksum
|
4 common/cmd_bootm.c Image data has correct checksum
|
-4 common/cmd_bootm.c Image is for unsupported architecture
|
5 common/cmd_bootm.c Architecture check OK
|
-5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
|
6 common/cmd_bootm.c Image Type check OK
|
-6 common/cmd_bootm.c gunzip uncompression error
|
-7 common/cmd_bootm.c Unimplemented compression type
|
7 common/cmd_bootm.c Uncompression OK
|
8 common/cmd_bootm.c No uncompress/copy overwrite error
|
-9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
|
|
9 common/image.c Start initial ramdisk verification
|
-10 common/image.c Ramdisk header has bad magic number
|
-11 common/image.c Ramdisk header has bad checksum
|
10 common/image.c Ramdisk header is OK
|
-12 common/image.c Ramdisk data has bad checksum
|
11 common/image.c Ramdisk data has correct checksum
|
12 common/image.c Ramdisk verification complete, start loading
|
-13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
|
13 common/image.c Start multifile image verification
|
14 common/image.c No initial ramdisk, no multifile, continue.
|
|
15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
|
|
-30 arch/powerpc/lib/board.c Fatal error, hang the system
|
-31 post/post.c POST test failed, detected by post_output_backlog()
|
-32 post/post.c POST test failed, detected by post_run_single()
|
|
34 common/cmd_doc.c before loading a Image from a DOC device
|
-35 common/cmd_doc.c Bad usage of "doc" command
|
35 common/cmd_doc.c correct usage of "doc" command
|
-36 common/cmd_doc.c No boot device
|
36 common/cmd_doc.c correct boot device
|
-37 common/cmd_doc.c Unknown Chip ID on boot device
|
37 common/cmd_doc.c correct chip ID found, device available
|
-38 common/cmd_doc.c Read Error on boot device
|
38 common/cmd_doc.c reading Image header from DOC device OK
|
-39 common/cmd_doc.c Image header has bad magic number
|
39 common/cmd_doc.c Image header has correct magic number
|
-40 common/cmd_doc.c Error reading Image from DOC device
|
40 common/cmd_doc.c Image header has correct magic number
|
41 common/cmd_ide.c before loading a Image from a IDE device
|
-42 common/cmd_ide.c Bad usage of "ide" command
|
42 common/cmd_ide.c correct usage of "ide" command
|
-43 common/cmd_ide.c No boot device
|
43 common/cmd_ide.c boot device found
|
-44 common/cmd_ide.c Device not available
|
44 common/cmd_ide.c Device available
|
-45 common/cmd_ide.c wrong partition selected
|
45 common/cmd_ide.c partition selected
|
-46 common/cmd_ide.c Unknown partition table
|
46 common/cmd_ide.c valid partition table found
|
-47 common/cmd_ide.c Invalid partition type
|
47 common/cmd_ide.c correct partition type
|
-48 common/cmd_ide.c Error reading Image Header on boot device
|
48 common/cmd_ide.c reading Image Header from IDE device OK
|
-49 common/cmd_ide.c Image header has bad magic number
|
49 common/cmd_ide.c Image header has correct magic number
|
-50 common/cmd_ide.c Image header has bad checksum
|
50 common/cmd_ide.c Image header has correct checksum
|
-51 common/cmd_ide.c Error reading Image from IDE device
|
51 common/cmd_ide.c reading Image from IDE device OK
|
52 common/cmd_nand.c before loading a Image from a NAND device
|
-53 common/cmd_nand.c Bad usage of "nand" command
|
53 common/cmd_nand.c correct usage of "nand" command
|
-54 common/cmd_nand.c No boot device
|
54 common/cmd_nand.c boot device found
|
-55 common/cmd_nand.c Unknown Chip ID on boot device
|
55 common/cmd_nand.c correct chip ID found, device available
|
-56 common/cmd_nand.c Error reading Image Header on boot device
|
56 common/cmd_nand.c reading Image Header from NAND device OK
|
-57 common/cmd_nand.c Image header has bad magic number
|
57 common/cmd_nand.c Image header has correct magic number
|
-58 common/cmd_nand.c Error reading Image from NAND device
|
58 common/cmd_nand.c reading Image from NAND device OK
|
|
-60 common/env_common.c Environment has a bad CRC, using default
|
|
64 net/eth.c starting with Ethernet configuration.
|
-64 net/eth.c no Ethernet found.
|
65 net/eth.c Ethernet found.
|
|
-80 common/cmd_net.c usage wrong
|
80 common/cmd_net.c before calling net_loop()
|
-81 common/cmd_net.c some error in net_loop() occurred
|
81 common/cmd_net.c net_loop() back without error
|
-82 common/cmd_net.c size == 0 (File with size 0 loaded)
|
82 common/cmd_net.c trying automatic boot
|
83 common/cmd_net.c running "source" command
|
-83 common/cmd_net.c some error in automatic boot or "source" command
|
84 common/cmd_net.c end without errors
|
|
FIT uImage format:
|
|
Arg Where When
|
100 common/cmd_bootm.c Kernel FIT Image has correct format
|
-100 common/cmd_bootm.c Kernel FIT Image has incorrect format
|
101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
|
-101 common/cmd_bootm.c Can't get configuration for kernel subimage
|
102 common/cmd_bootm.c Kernel unit name specified
|
-103 common/cmd_bootm.c Can't get kernel subimage node offset
|
103 common/cmd_bootm.c Found configuration node
|
104 common/cmd_bootm.c Got kernel subimage node offset
|
-104 common/cmd_bootm.c Kernel subimage hash verification failed
|
105 common/cmd_bootm.c Kernel subimage hash verification OK
|
-105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
|
106 common/cmd_bootm.c Architecture check OK
|
-106 common/cmd_bootm.c Kernel subimage has wrong type
|
107 common/cmd_bootm.c Kernel subimage type OK
|
-107 common/cmd_bootm.c Can't get kernel subimage data/size
|
108 common/cmd_bootm.c Got kernel subimage data/size
|
-108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
|
-109 common/cmd_bootm.c Can't get kernel subimage type
|
-110 common/cmd_bootm.c Can't get kernel subimage comp
|
-111 common/cmd_bootm.c Can't get kernel subimage os
|
-112 common/cmd_bootm.c Can't get kernel subimage load address
|
-113 common/cmd_bootm.c Image uncompress/copy overwrite error
|
|
120 common/image.c Start initial ramdisk verification
|
-120 common/image.c Ramdisk FIT image has incorrect format
|
121 common/image.c Ramdisk FIT image has correct format
|
122 common/image.c No ramdisk subimage unit name, using configuration
|
-122 common/image.c Can't get configuration for ramdisk subimage
|
123 common/image.c Ramdisk unit name specified
|
-124 common/image.c Can't get ramdisk subimage node offset
|
125 common/image.c Got ramdisk subimage node offset
|
-125 common/image.c Ramdisk subimage hash verification failed
|
126 common/image.c Ramdisk subimage hash verification OK
|
-126 common/image.c Ramdisk subimage for unsupported architecture
|
127 common/image.c Architecture check OK
|
-127 common/image.c Can't get ramdisk subimage data/size
|
128 common/image.c Got ramdisk subimage data/size
|
129 common/image.c Can't get ramdisk load address
|
-129 common/image.c Got ramdisk load address
|
|
-130 common/cmd_doc.c Incorrect FIT image format
|
131 common/cmd_doc.c FIT image format OK
|
|
-140 common/cmd_ide.c Incorrect FIT image format
|
141 common/cmd_ide.c FIT image format OK
|
|
-150 common/cmd_nand.c Incorrect FIT image format
|
151 common/cmd_nand.c FIT image format OK
|
|
- legacy image format:
|
CONFIG_IMAGE_FORMAT_LEGACY
|
enables the legacy image format support in U-Boot.
|
|
Default:
|
enabled if CONFIG_FIT_SIGNATURE is not defined.
|
|
CONFIG_DISABLE_IMAGE_LEGACY
|
disable the legacy image format
|
|
This define is introduced, as the legacy image format is
|
enabled per default for backward compatibility.
|
|
- Standalone program support:
|
CONFIG_STANDALONE_LOAD_ADDR
|
|
This option defines a board specific value for the
|
address where standalone program gets loaded, thus
|
overwriting the architecture dependent default
|
settings.
|
|
- Frame Buffer Address:
|
CONFIG_FB_ADDR
|
|
Define CONFIG_FB_ADDR if you want to use specific
|
address for frame buffer. This is typically the case
|
when using a graphics controller has separate video
|
memory. U-Boot will then place the frame buffer at
|
the given address instead of dynamically reserving it
|
in system RAM by calling lcd_setmem(), which grabs
|
the memory for the frame buffer depending on the
|
configured panel size.
|
|
Please see board_init_f function.
|
|
- Automatic software updates via TFTP server
|
CONFIG_UPDATE_TFTP
|
CONFIG_UPDATE_TFTP_CNT_MAX
|
CONFIG_UPDATE_TFTP_MSEC_MAX
|
|
These options enable and control the auto-update feature;
|
for a more detailed description refer to doc/README.update.
|
|
- MTD Support (mtdparts command, UBI support)
|
CONFIG_MTD_UBI_WL_THRESHOLD
|
This parameter defines the maximum difference between the highest
|
erase counter value and the lowest erase counter value of eraseblocks
|
of UBI devices. When this threshold is exceeded, UBI starts performing
|
wear leveling by means of moving data from eraseblock with low erase
|
counter to eraseblocks with high erase counter.
|
|
The default value should be OK for SLC NAND flashes, NOR flashes and
|
other flashes which have eraseblock life-cycle 100000 or more.
|
However, in case of MLC NAND flashes which typically have eraseblock
|
life-cycle less than 10000, the threshold should be lessened (e.g.,
|
to 128 or 256, although it does not have to be power of 2).
|
|
default: 4096
|
|
CONFIG_MTD_UBI_BEB_LIMIT
|
This option specifies the maximum bad physical eraseblocks UBI
|
expects on the MTD device (per 1024 eraseblocks). If the
|
underlying flash does not admit of bad eraseblocks (e.g. NOR
|
flash), this value is ignored.
|
|
NAND datasheets often specify the minimum and maximum NVM
|
(Number of Valid Blocks) for the flashes' endurance lifetime.
|
The maximum expected bad eraseblocks per 1024 eraseblocks
|
then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
|
which gives 20 for most NANDs (MaxNVB is basically the total
|
count of eraseblocks on the chip).
|
|
To put it differently, if this value is 20, UBI will try to
|
reserve about 1.9% of physical eraseblocks for bad blocks
|
handling. And that will be 1.9% of eraseblocks on the entire
|
NAND chip, not just the MTD partition UBI attaches. This means
|
that if you have, say, a NAND flash chip admits maximum 40 bad
|
eraseblocks, and it is split on two MTD partitions of the same
|
size, UBI will reserve 40 eraseblocks when attaching a
|
partition.
|
|
default: 20
|
|
CONFIG_MTD_UBI_FASTMAP
|
Fastmap is a mechanism which allows attaching an UBI device
|
in nearly constant time. Instead of scanning the whole MTD device it
|
only has to locate a checkpoint (called fastmap) on the device.
|
The on-flash fastmap contains all information needed to attach
|
the device. Using fastmap makes only sense on large devices where
|
attaching by scanning takes long. UBI will not automatically install
|
a fastmap on old images, but you can set the UBI parameter
|
CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
|
that fastmap-enabled images are still usable with UBI implementations
|
without fastmap support. On typical flash devices the whole fastmap
|
fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
|
|
CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
|
Set this parameter to enable fastmap automatically on images
|
without a fastmap.
|
default: 0
|
|
CONFIG_MTD_UBI_FM_DEBUG
|
Enable UBI fastmap debug
|
default: 0
|
|
- UBIFS support
|
CONFIG_UBIFS_SILENCE_MSG
|
|
Make the verbose messages from UBIFS stop printing. This leaves
|
warnings and errors enabled.
|
|
- SPL framework
|
CONFIG_SPL
|
Enable building of SPL globally.
|
|
CONFIG_SPL_LDSCRIPT
|
LDSCRIPT for linking the SPL binary.
|
|
CONFIG_SPL_MAX_FOOTPRINT
|
Maximum size in memory allocated to the SPL, BSS included.
|
When defined, the linker checks that the actual memory
|
used by SPL from _start to __bss_end does not exceed it.
|
CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
|
must not be both defined at the same time.
|
|
CONFIG_SPL_MAX_SIZE
|
Maximum size of the SPL image (text, data, rodata, and
|
linker lists sections), BSS excluded.
|
When defined, the linker checks that the actual size does
|
not exceed it.
|
|
CONFIG_SPL_TEXT_BASE
|
TEXT_BASE for linking the SPL binary.
|
|
CONFIG_SPL_RELOC_TEXT_BASE
|
Address to relocate to. If unspecified, this is equal to
|
CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
|
|
CONFIG_SPL_BSS_START_ADDR
|
Link address for the BSS within the SPL binary.
|
|
CONFIG_SPL_BSS_MAX_SIZE
|
Maximum size in memory allocated to the SPL BSS.
|
When defined, the linker checks that the actual memory used
|
by SPL from __bss_start to __bss_end does not exceed it.
|
CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
|
must not be both defined at the same time.
|
|
CONFIG_SPL_STACK
|
Adress of the start of the stack SPL will use
|
|
CONFIG_SPL_PANIC_ON_RAW_IMAGE
|
When defined, SPL will panic() if the image it has
|
loaded does not have a signature.
|
Defining this is useful when code which loads images
|
in SPL cannot guarantee that absolutely all read errors
|
will be caught.
|
An example is the LPC32XX MLC NAND driver, which will
|
consider that a completely unreadable NAND block is bad,
|
and thus should be skipped silently.
|
|
CONFIG_SPL_RELOC_STACK
|
Adress of the start of the stack SPL will use after
|
relocation. If unspecified, this is equal to
|
CONFIG_SPL_STACK.
|
|
CONFIG_SYS_SPL_MALLOC_START
|
Starting address of the malloc pool used in SPL.
|
When this option is set the full malloc is used in SPL and
|
it is set up by spl_init() and before that, the simple malloc()
|
can be used if CONFIG_SYS_MALLOC_F is defined.
|
|
CONFIG_SYS_SPL_MALLOC_SIZE
|
The size of the malloc pool used in SPL.
|
|
CONFIG_SPL_FRAMEWORK
|
Enable the SPL framework under common/. This framework
|
supports MMC, NAND and YMODEM loading of U-Boot and NAND
|
NAND loading of the Linux Kernel.
|
|
CONFIG_SPL_OS_BOOT
|
Enable booting directly to an OS from SPL.
|
See also: doc/README.falcon
|
|
CONFIG_SPL_DISPLAY_PRINT
|
For ARM, enable an optional function to print more information
|
about the running system.
|
|
CONFIG_SPL_INIT_MINIMAL
|
Arch init code should be built for a very small image
|
|
CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
|
Partition on the MMC to load U-Boot from when the MMC is being
|
used in raw mode
|
|
CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
|
Sector to load kernel uImage from when MMC is being
|
used in raw mode (for Falcon mode)
|
|
CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
|
CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
|
Sector and number of sectors to load kernel argument
|
parameters from when MMC is being used in raw mode
|
(for falcon mode)
|
|
CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
|
Partition on the MMC to load U-Boot from when the MMC is being
|
used in fs mode
|
|
CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
|
Filename to read to load U-Boot when reading from filesystem
|
|
CONFIG_SPL_FS_LOAD_KERNEL_NAME
|
Filename to read to load kernel uImage when reading
|
from filesystem (for Falcon mode)
|
|
CONFIG_SPL_FS_LOAD_ARGS_NAME
|
Filename to read to load kernel argument parameters
|
when reading from filesystem (for Falcon mode)
|
|
CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
|
Set this for NAND SPL on PPC mpc83xx targets, so that
|
start.S waits for the rest of the SPL to load before
|
continuing (the hardware starts execution after just
|
loading the first page rather than the full 4K).
|
|
CONFIG_SPL_SKIP_RELOCATE
|
Avoid SPL relocation
|
|
CONFIG_SPL_NAND_BASE
|
Include nand_base.c in the SPL. Requires
|
CONFIG_SPL_NAND_DRIVERS.
|
|
CONFIG_SPL_NAND_DRIVERS
|
SPL uses normal NAND drivers, not minimal drivers.
|
|
CONFIG_SPL_NAND_IDENT
|
SPL uses the chip ID list to identify the NAND flash.
|
Requires CONFIG_SPL_NAND_BASE.
|
|
CONFIG_SPL_NAND_ECC
|
Include standard software ECC in the SPL
|
|
CONFIG_SPL_NAND_SIMPLE
|
Support for NAND boot using simple NAND drivers that
|
expose the cmd_ctrl() interface.
|
|
CONFIG_SPL_UBI
|
Support for a lightweight UBI (fastmap) scanner and
|
loader
|
|
CONFIG_SPL_NAND_RAW_ONLY
|
Support to boot only raw u-boot.bin images. Use this only
|
if you need to save space.
|
|
CONFIG_SPL_COMMON_INIT_DDR
|
Set for common ddr init with serial presence detect in
|
SPL binary.
|
|
CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
|
CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
|
CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
|
CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
|
CONFIG_SYS_NAND_ECCBYTES
|
Defines the size and behavior of the NAND that SPL uses
|
to read U-Boot
|
|
CONFIG_SPL_NAND_BOOT
|
Add support NAND boot
|
|
CONFIG_SYS_NAND_U_BOOT_OFFS
|
Location in NAND to read U-Boot from
|
|
CONFIG_SYS_NAND_U_BOOT_DST
|
Location in memory to load U-Boot to
|
|
CONFIG_SYS_NAND_U_BOOT_SIZE
|
Size of image to load
|
|
CONFIG_SYS_NAND_U_BOOT_START
|
Entry point in loaded image to jump to
|
|
CONFIG_SYS_NAND_HW_ECC_OOBFIRST
|
Define this if you need to first read the OOB and then the
|
data. This is used, for example, on davinci platforms.
|
|
CONFIG_SPL_RAM_DEVICE
|
Support for running image already present in ram, in SPL binary
|
|
CONFIG_SPL_PAD_TO
|
Image offset to which the SPL should be padded before appending
|
the SPL payload. By default, this is defined as
|
CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
|
CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
|
payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
|
|
CONFIG_SPL_TARGET
|
Final target image containing SPL and payload. Some SPLs
|
use an arch-specific makefile fragment instead, for
|
example if more than one image needs to be produced.
|
|
CONFIG_FIT_SPL_PRINT
|
Printing information about a FIT image adds quite a bit of
|
code to SPL. So this is normally disabled in SPL. Use this
|
option to re-enable it. This will affect the output of the
|
bootm command when booting a FIT image.
|
|
- TPL framework
|
CONFIG_TPL
|
Enable building of TPL globally.
|
|
CONFIG_TPL_PAD_TO
|
Image offset to which the TPL should be padded before appending
|
the TPL payload. By default, this is defined as
|
CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
|
CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
|
payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
|
|
- Interrupt support (PPC):
|
|
There are common interrupt_init() and timer_interrupt()
|
for all PPC archs. interrupt_init() calls interrupt_init_cpu()
|
for CPU specific initialization. interrupt_init_cpu()
|
should set decrementer_count to appropriate value. If
|
CPU resets decrementer automatically after interrupt
|
(ppc4xx) it should set decrementer_count to zero.
|
timer_interrupt() calls timer_interrupt_cpu() for CPU
|
specific handling. If board has watchdog / status_led
|
/ other_activity_monitor it works automatically from
|
general timer_interrupt().
|
|
|
Board initialization settings:
|
------------------------------
|
|
During Initialization u-boot calls a number of board specific functions
|
to allow the preparation of board specific prerequisites, e.g. pin setup
|
before drivers are initialized. To enable these callbacks the
|
following configuration macros have to be defined. Currently this is
|
architecture specific, so please check arch/your_architecture/lib/board.c
|
typically in board_init_f() and board_init_r().
|
|
- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
|
- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
|
- CONFIG_BOARD_LATE_INIT: Call board_late_init()
|
- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
|
|
Configuration Settings:
|
-----------------------
|
|
- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
|
Optionally it can be defined to support 64-bit memory commands.
|
|
- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
|
undefine this when you're short of memory.
|
|
- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
|
width of the commands listed in the 'help' command output.
|
|
- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
|
prompt for user input.
|
|
- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
|
|
- CONFIG_SYS_PBSIZE: Buffer size for Console output
|
|
- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
|
|
- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
|
the application (usually a Linux kernel) when it is
|
booted
|
|
- CONFIG_SYS_BAUDRATE_TABLE:
|
List of legal baudrate settings for this board.
|
|
- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
|
Begin and End addresses of the area used by the
|
simple memory test.
|
|
- CONFIG_SYS_ALT_MEMTEST:
|
Enable an alternate, more extensive memory test.
|
|
- CONFIG_SYS_MEMTEST_SCRATCH:
|
Scratch address used by the alternate memory test
|
You only need to set this if address zero isn't writeable
|
|
- CONFIG_SYS_MEM_RESERVE_SECURE
|
Only implemented for ARMv8 for now.
|
If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
|
is substracted from total RAM and won't be reported to OS.
|
This memory can be used as secure memory. A variable
|
gd->arch.secure_ram is used to track the location. In systems
|
the RAM base is not zero, or RAM is divided into banks,
|
this variable needs to be recalcuated to get the address.
|
|
- CONFIG_SYS_MEM_TOP_HIDE:
|
If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
|
this specified memory area will get subtracted from the top
|
(end) of RAM and won't get "touched" at all by U-Boot. By
|
fixing up gd->ram_size the Linux kernel should gets passed
|
the now "corrected" memory size and won't touch it either.
|
This should work for arch/ppc and arch/powerpc. Only Linux
|
board ports in arch/powerpc with bootwrapper support that
|
recalculate the memory size from the SDRAM controller setup
|
will have to get fixed in Linux additionally.
|
|
This option can be used as a workaround for the 440EPx/GRx
|
CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
|
be touched.
|
|
WARNING: Please make sure that this value is a multiple of
|
the Linux page size (normally 4k). If this is not the case,
|
then the end address of the Linux memory will be located at a
|
non page size aligned address and this could cause major
|
problems.
|
|
- CONFIG_SYS_LOADS_BAUD_CHANGE:
|
Enable temporary baudrate change while serial download
|
|
- CONFIG_SYS_SDRAM_BASE:
|
Physical start address of SDRAM. _Must_ be 0 here.
|
|
- CONFIG_SYS_FLASH_BASE:
|
Physical start address of Flash memory.
|
|
- CONFIG_SYS_MONITOR_BASE:
|
Physical start address of boot monitor code (set by
|
make config files to be same as the text base address
|
(CONFIG_SYS_TEXT_BASE) used when linking) - same as
|
CONFIG_SYS_FLASH_BASE when booting from flash.
|
|
- CONFIG_SYS_MONITOR_LEN:
|
Size of memory reserved for monitor code, used to
|
determine _at_compile_time_ (!) if the environment is
|
embedded within the U-Boot image, or in a separate
|
flash sector.
|
|
- CONFIG_SYS_MALLOC_LEN:
|
Size of DRAM reserved for malloc() use.
|
|
- CONFIG_SYS_MALLOC_F_LEN
|
Size of the malloc() pool for use before relocation. If
|
this is defined, then a very simple malloc() implementation
|
will become available before relocation. The address is just
|
below the global data, and the stack is moved down to make
|
space.
|
|
This feature allocates regions with increasing addresses
|
within the region. calloc() is supported, but realloc()
|
is not available. free() is supported but does nothing.
|
The memory will be freed (or in fact just forgotten) when
|
U-Boot relocates itself.
|
|
- CONFIG_SYS_MALLOC_SIMPLE
|
Provides a simple and small malloc() and calloc() for those
|
boards which do not use the full malloc in SPL (which is
|
enabled with CONFIG_SYS_SPL_MALLOC_START).
|
|
- CONFIG_SYS_NONCACHED_MEMORY:
|
Size of non-cached memory area. This area of memory will be
|
typically located right below the malloc() area and mapped
|
uncached in the MMU. This is useful for drivers that would
|
otherwise require a lot of explicit cache maintenance. For
|
some drivers it's also impossible to properly maintain the
|
cache. For example if the regions that need to be flushed
|
are not a multiple of the cache-line size, *and* padding
|
cannot be allocated between the regions to align them (i.e.
|
if the HW requires a contiguous array of regions, and the
|
size of each region is not cache-aligned), then a flush of
|
one region may result in overwriting data that hardware has
|
written to another region in the same cache-line. This can
|
happen for example in network drivers where descriptors for
|
buffers are typically smaller than the CPU cache-line (e.g.
|
16 bytes vs. 32 or 64 bytes).
|
|
Non-cached memory is only supported on 32-bit ARM at present.
|
|
- CONFIG_SYS_BOOTM_LEN:
|
Normally compressed uImages are limited to an
|
uncompressed size of 8 MBytes. If this is not enough,
|
you can define CONFIG_SYS_BOOTM_LEN in your board config file
|
to adjust this setting to your needs.
|
|
- CONFIG_SYS_BOOTMAPSZ:
|
Maximum size of memory mapped by the startup code of
|
the Linux kernel; all data that must be processed by
|
the Linux kernel (bd_info, boot arguments, FDT blob if
|
used) must be put below this limit, unless "bootm_low"
|
environment variable is defined and non-zero. In such case
|
all data for the Linux kernel must be between "bootm_low"
|
and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
|
variable "bootm_mapsize" will override the value of
|
CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
|
then the value in "bootm_size" will be used instead.
|
|
- CONFIG_SYS_BOOT_RAMDISK_HIGH:
|
Enable initrd_high functionality. If defined then the
|
initrd_high feature is enabled and the bootm ramdisk subcommand
|
is enabled.
|
|
- CONFIG_SYS_BOOT_GET_CMDLINE:
|
Enables allocating and saving kernel cmdline in space between
|
"bootm_low" and "bootm_low" + BOOTMAPSZ.
|
|
- CONFIG_SYS_BOOT_GET_KBD:
|
Enables allocating and saving a kernel copy of the bd_info in
|
space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
|
|
- CONFIG_SYS_MAX_FLASH_BANKS:
|
Max number of Flash memory banks
|
|
- CONFIG_SYS_MAX_FLASH_SECT:
|
Max number of sectors on a Flash chip
|
|
- CONFIG_SYS_FLASH_ERASE_TOUT:
|
Timeout for Flash erase operations (in ms)
|
|
- CONFIG_SYS_FLASH_WRITE_TOUT:
|
Timeout for Flash write operations (in ms)
|
|
- CONFIG_SYS_FLASH_LOCK_TOUT
|
Timeout for Flash set sector lock bit operation (in ms)
|
|
- CONFIG_SYS_FLASH_UNLOCK_TOUT
|
Timeout for Flash clear lock bits operation (in ms)
|
|
- CONFIG_SYS_FLASH_PROTECTION
|
If defined, hardware flash sectors protection is used
|
instead of U-Boot software protection.
|
|
- CONFIG_SYS_DIRECT_FLASH_TFTP:
|
|
Enable TFTP transfers directly to flash memory;
|
without this option such a download has to be
|
performed in two steps: (1) download to RAM, and (2)
|
copy from RAM to flash.
|
|
The two-step approach is usually more reliable, since
|
you can check if the download worked before you erase
|
the flash, but in some situations (when system RAM is
|
too limited to allow for a temporary copy of the
|
downloaded image) this option may be very useful.
|
|
- CONFIG_SYS_FLASH_CFI:
|
Define if the flash driver uses extra elements in the
|
common flash structure for storing flash geometry.
|
|
- CONFIG_FLASH_CFI_DRIVER
|
This option also enables the building of the cfi_flash driver
|
in the drivers directory
|
|
- CONFIG_FLASH_CFI_MTD
|
This option enables the building of the cfi_mtd driver
|
in the drivers directory. The driver exports CFI flash
|
to the MTD layer.
|
|
- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
|
Use buffered writes to flash.
|
|
- CONFIG_FLASH_SPANSION_S29WS_N
|
s29ws-n MirrorBit flash has non-standard addresses for buffered
|
write commands.
|
|
- CONFIG_SYS_FLASH_QUIET_TEST
|
If this option is defined, the common CFI flash doesn't
|
print it's warning upon not recognized FLASH banks. This
|
is useful, if some of the configured banks are only
|
optionally available.
|
|
- CONFIG_FLASH_SHOW_PROGRESS
|
If defined (must be an integer), print out countdown
|
digits and dots. Recommended value: 45 (9..1) for 80
|
column displays, 15 (3..1) for 40 column displays.
|
|
- CONFIG_FLASH_VERIFY
|
If defined, the content of the flash (destination) is compared
|
against the source after the write operation. An error message
|
will be printed when the contents are not identical.
|
Please note that this option is useless in nearly all cases,
|
since such flash programming errors usually are detected earlier
|
while unprotecting/erasing/programming. Please only enable
|
this option if you really know what you are doing.
|
|
- CONFIG_SYS_RX_ETH_BUFFER:
|
Defines the number of Ethernet receive buffers. On some
|
Ethernet controllers it is recommended to set this value
|
to 8 or even higher (EEPRO100 or 405 EMAC), since all
|
buffers can be full shortly after enabling the interface
|
on high Ethernet traffic.
|
Defaults to 4 if not defined.
|
|
- CONFIG_ENV_MAX_ENTRIES
|
|
Maximum number of entries in the hash table that is used
|
internally to store the environment settings. The default
|
setting is supposed to be generous and should work in most
|
cases. This setting can be used to tune behaviour; see
|
lib/hashtable.c for details.
|
|
- CONFIG_ENV_FLAGS_LIST_DEFAULT
|
- CONFIG_ENV_FLAGS_LIST_STATIC
|
Enable validation of the values given to environment variables when
|
calling env set. Variables can be restricted to only decimal,
|
hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
|
the variables can also be restricted to IP address or MAC address.
|
|
The format of the list is:
|
type_attribute = [s|d|x|b|i|m]
|
access_attribute = [a|r|o|c]
|
attributes = type_attribute[access_attribute]
|
entry = variable_name[:attributes]
|
list = entry[,list]
|
|
The type attributes are:
|
s - String (default)
|
d - Decimal
|
x - Hexadecimal
|
b - Boolean ([1yYtT|0nNfF])
|
i - IP address
|
m - MAC address
|
|
The access attributes are:
|
a - Any (default)
|
r - Read-only
|
o - Write-once
|
c - Change-default
|
|
- CONFIG_ENV_FLAGS_LIST_DEFAULT
|
Define this to a list (string) to define the ".flags"
|
environment variable in the default or embedded environment.
|
|
- CONFIG_ENV_FLAGS_LIST_STATIC
|
Define this to a list (string) to define validation that
|
should be done if an entry is not found in the ".flags"
|
environment variable. To override a setting in the static
|
list, simply add an entry for the same variable name to the
|
".flags" variable.
|
|
If CONFIG_REGEX is defined, the variable_name above is evaluated as a
|
regular expression. This allows multiple variables to define the same
|
flags without explicitly listing them for each variable.
|
|
- CONFIG_ENV_ACCESS_IGNORE_FORCE
|
If defined, don't allow the -f switch to env set override variable
|
access flags.
|
|
- CONFIG_USE_STDINT
|
If stdint.h is available with your toolchain you can define this
|
option to enable it. You can provide option 'USE_STDINT=1' when
|
building U-Boot to enable this.
|
|
The following definitions that deal with the placement and management
|
of environment data (variable area); in general, we support the
|
following configurations:
|
|
- CONFIG_BUILD_ENVCRC:
|
|
Builds up envcrc with the target environment so that external utils
|
may easily extract it and embed it in final U-Boot images.
|
|
BE CAREFUL! The first access to the environment happens quite early
|
in U-Boot initialization (when we try to get the setting of for the
|
console baudrate). You *MUST* have mapped your NVRAM area then, or
|
U-Boot will hang.
|
|
Please note that even with NVRAM we still use a copy of the
|
environment in RAM: we could work on NVRAM directly, but we want to
|
keep settings there always unmodified except somebody uses "saveenv"
|
to save the current settings.
|
|
BE CAREFUL! For some special cases, the local device can not use
|
"saveenv" command. For example, the local device will get the
|
environment stored in a remote NOR flash by SRIO or PCIE link,
|
but it can not erase, write this NOR flash by SRIO or PCIE interface.
|
|
- CONFIG_NAND_ENV_DST
|
|
Defines address in RAM to which the nand_spl code should copy the
|
environment. If redundant environment is used, it will be copied to
|
CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
|
|
Please note that the environment is read-only until the monitor
|
has been relocated to RAM and a RAM copy of the environment has been
|
created; also, when using EEPROM you will have to use env_get_f()
|
until then to read environment variables.
|
|
The environment is protected by a CRC32 checksum. Before the monitor
|
is relocated into RAM, as a result of a bad CRC you will be working
|
with the compiled-in default environment - *silently*!!! [This is
|
necessary, because the first environment variable we need is the
|
"baudrate" setting for the console - if we have a bad CRC, we don't
|
have any device yet where we could complain.]
|
|
Note: once the monitor has been relocated, then it will complain if
|
the default environment is used; a new CRC is computed as soon as you
|
use the "saveenv" command to store a valid environment.
|
|
- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
|
Echo the inverted Ethernet link state to the fault LED.
|
|
Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
|
also needs to be defined.
|
|
- CONFIG_SYS_FAULT_MII_ADDR:
|
MII address of the PHY to check for the Ethernet link state.
|
|
- CONFIG_NS16550_MIN_FUNCTIONS:
|
Define this if you desire to only have use of the NS16550_init
|
and NS16550_putc functions for the serial driver located at
|
drivers/serial/ns16550.c. This option is useful for saving
|
space for already greatly restricted images, including but not
|
limited to NAND_SPL configurations.
|
|
- CONFIG_DISPLAY_BOARDINFO
|
Display information about the board that U-Boot is running on
|
when U-Boot starts up. The board function checkboard() is called
|
to do this.
|
|
- CONFIG_DISPLAY_BOARDINFO_LATE
|
Similar to the previous option, but display this information
|
later, once stdio is running and output goes to the LCD, if
|
present.
|
|
- CONFIG_BOARD_SIZE_LIMIT:
|
Maximum size of the U-Boot image. When defined, the
|
build system checks that the actual size does not
|
exceed it.
|
|
Low Level (hardware related) configuration options:
|
---------------------------------------------------
|
|
- CONFIG_SYS_CACHELINE_SIZE:
|
Cache Line Size of the CPU.
|
|
- CONFIG_SYS_CCSRBAR_DEFAULT:
|
Default (power-on reset) physical address of CCSR on Freescale
|
PowerPC SOCs.
|
|
- CONFIG_SYS_CCSRBAR:
|
Virtual address of CCSR. On a 32-bit build, this is typically
|
the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
|
|
- CONFIG_SYS_CCSRBAR_PHYS:
|
Physical address of CCSR. CCSR can be relocated to a new
|
physical address, if desired. In this case, this macro should
|
be set to that address. Otherwise, it should be set to the
|
same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
|
is typically relocated on 36-bit builds. It is recommended
|
that this macro be defined via the _HIGH and _LOW macros:
|
|
#define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
|
* 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
|
|
- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
|
Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
|
either 0 (32-bit build) or 0xF (36-bit build). This macro is
|
used in assembly code, so it must not contain typecasts or
|
integer size suffixes (e.g. "ULL").
|
|
- CONFIG_SYS_CCSRBAR_PHYS_LOW:
|
Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
|
used in assembly code, so it must not contain typecasts or
|
integer size suffixes (e.g. "ULL").
|
|
- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
|
If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
|
forced to a value that ensures that CCSR is not relocated.
|
|
- Floppy Disk Support:
|
CONFIG_SYS_FDC_DRIVE_NUMBER
|
|
the default drive number (default value 0)
|
|
CONFIG_SYS_ISA_IO_STRIDE
|
|
defines the spacing between FDC chipset registers
|
(default value 1)
|
|
CONFIG_SYS_ISA_IO_OFFSET
|
|
defines the offset of register from address. It
|
depends on which part of the data bus is connected to
|
the FDC chipset. (default value 0)
|
|
If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
|
CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
|
default value.
|
|
if CONFIG_SYS_FDC_HW_INIT is defined, then the function
|
fdc_hw_init() is called at the beginning of the FDC
|
setup. fdc_hw_init() must be provided by the board
|
source code. It is used to make hardware-dependent
|
initializations.
|
|
- CONFIG_IDE_AHB:
|
Most IDE controllers were designed to be connected with PCI
|
interface. Only few of them were designed for AHB interface.
|
When software is doing ATA command and data transfer to
|
IDE devices through IDE-AHB controller, some additional
|
registers accessing to these kind of IDE-AHB controller
|
is required.
|
|
- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
|
DO NOT CHANGE unless you know exactly what you're
|
doing! (11-4) [MPC8xx systems only]
|
|
- CONFIG_SYS_INIT_RAM_ADDR:
|
|
Start address of memory area that can be used for
|
initial data and stack; please note that this must be
|
writable memory that is working WITHOUT special
|
initialization, i. e. you CANNOT use normal RAM which
|
will become available only after programming the
|
memory controller and running certain initialization
|
sequences.
|
|
U-Boot uses the following memory types:
|
- MPC8xx: IMMR (internal memory of the CPU)
|
|
- CONFIG_SYS_GBL_DATA_OFFSET:
|
|
Offset of the initial data structure in the memory
|
area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
|
CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
|
data is located at the end of the available space
|
(sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
|
GENERATED_GBL_DATA_SIZE), and the initial stack is just
|
below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
|
CONFIG_SYS_GBL_DATA_OFFSET) downward.
|
|
Note:
|
On the MPC824X (or other systems that use the data
|
cache for initial memory) the address chosen for
|
CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
|
point to an otherwise UNUSED address space between
|
the top of RAM and the start of the PCI space.
|
|
- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
|
|
- CONFIG_SYS_OR_TIMING_SDRAM:
|
SDRAM timing
|
|
- CONFIG_SYS_MAMR_PTA:
|
periodic timer for refresh
|
|
- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
|
CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
|
CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
|
CONFIG_SYS_BR1_PRELIM:
|
Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
|
|
- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
|
CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
|
CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
|
Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
|
|
- CONFIG_PCI_ENUM_ONLY
|
Only scan through and get the devices on the buses.
|
Don't do any setup work, presumably because someone or
|
something has already done it, and we don't need to do it
|
a second time. Useful for platforms that are pre-booted
|
by coreboot or similar.
|
|
- CONFIG_PCI_INDIRECT_BRIDGE:
|
Enable support for indirect PCI bridges.
|
|
- CONFIG_SYS_SRIO:
|
Chip has SRIO or not
|
|
- CONFIG_SRIO1:
|
Board has SRIO 1 port available
|
|
- CONFIG_SRIO2:
|
Board has SRIO 2 port available
|
|
- CONFIG_SRIO_PCIE_BOOT_MASTER
|
Board can support master function for Boot from SRIO and PCIE
|
|
- CONFIG_SYS_SRIOn_MEM_VIRT:
|
Virtual Address of SRIO port 'n' memory region
|
|
- CONFIG_SYS_SRIOn_MEM_PHYS:
|
Physical Address of SRIO port 'n' memory region
|
|
- CONFIG_SYS_SRIOn_MEM_SIZE:
|
Size of SRIO port 'n' memory region
|
|
- CONFIG_SYS_NAND_BUSWIDTH_16BIT
|
Defined to tell the NAND controller that the NAND chip is using
|
a 16 bit bus.
|
Not all NAND drivers use this symbol.
|
Example of drivers that use it:
|
- drivers/mtd/nand/raw/ndfc.c
|
- drivers/mtd/nand/raw/mxc_nand.c
|
|
- CONFIG_SYS_NDFC_EBC0_CFG
|
Sets the EBC0_CFG register for the NDFC. If not defined
|
a default value will be used.
|
|
- CONFIG_SPD_EEPROM
|
Get DDR timing information from an I2C EEPROM. Common
|
with pluggable memory modules such as SODIMMs
|
|
SPD_EEPROM_ADDRESS
|
I2C address of the SPD EEPROM
|
|
- CONFIG_SYS_SPD_BUS_NUM
|
If SPD EEPROM is on an I2C bus other than the first
|
one, specify here. Note that the value must resolve
|
to something your driver can deal with.
|
|
- CONFIG_SYS_DDR_RAW_TIMING
|
Get DDR timing information from other than SPD. Common with
|
soldered DDR chips onboard without SPD. DDR raw timing
|
parameters are extracted from datasheet and hard-coded into
|
header files or board specific files.
|
|
- CONFIG_FSL_DDR_INTERACTIVE
|
Enable interactive DDR debugging. See doc/README.fsl-ddr.
|
|
- CONFIG_FSL_DDR_SYNC_REFRESH
|
Enable sync of refresh for multiple controllers.
|
|
- CONFIG_FSL_DDR_BIST
|
Enable built-in memory test for Freescale DDR controllers.
|
|
- CONFIG_SYS_83XX_DDR_USES_CS0
|
Only for 83xx systems. If specified, then DDR should
|
be configured using CS0 and CS1 instead of CS2 and CS3.
|
|
- CONFIG_RMII
|
Enable RMII mode for all FECs.
|
Note that this is a global option, we can't
|
have one FEC in standard MII mode and another in RMII mode.
|
|
- CONFIG_CRC32_VERIFY
|
Add a verify option to the crc32 command.
|
The syntax is:
|
|
=> crc32 -v <address> <count> <crc32>
|
|
Where address/count indicate a memory area
|
and crc32 is the correct crc32 which the
|
area should have.
|
|
- CONFIG_LOOPW
|
Add the "loopw" memory command. This only takes effect if
|
the memory commands are activated globally (CONFIG_CMD_MEMORY).
|
|
- CONFIG_MX_CYCLIC
|
Add the "mdc" and "mwc" memory commands. These are cyclic
|
"md/mw" commands.
|
Examples:
|
|
=> mdc.b 10 4 500
|
This command will print 4 bytes (10,11,12,13) each 500 ms.
|
|
=> mwc.l 100 12345678 10
|
This command will write 12345678 to address 100 all 10 ms.
|
|
This only takes effect if the memory commands are activated
|
globally (CONFIG_CMD_MEMORY).
|
|
- CONFIG_SKIP_LOWLEVEL_INIT
|
[ARM, NDS32, MIPS only] If this variable is defined, then certain
|
low level initializations (like setting up the memory
|
controller) are omitted and/or U-Boot does not
|
relocate itself into RAM.
|
|
Normally this variable MUST NOT be defined. The only
|
exception is when U-Boot is loaded (to RAM) by some
|
other boot loader or by a debugger which performs
|
these initializations itself.
|
|
- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
|
[ARM926EJ-S only] This allows just the call to lowlevel_init()
|
to be skipped. The normal CP15 init (such as enabling the
|
instruction cache) is still performed.
|
|
- CONFIG_SPL_BUILD
|
Modifies the behaviour of start.S when compiling a loader
|
that is executed before the actual U-Boot. E.g. when
|
compiling a NAND SPL.
|
|
- CONFIG_TPL_BUILD
|
Modifies the behaviour of start.S when compiling a loader
|
that is executed after the SPL and before the actual U-Boot.
|
It is loaded by the SPL.
|
|
- CONFIG_SYS_MPC85XX_NO_RESETVEC
|
Only for 85xx systems. If this variable is specified, the section
|
.resetvec is not kept and the section .bootpg is placed in the
|
previous 4k of the .text section.
|
|
- CONFIG_ARCH_MAP_SYSMEM
|
Generally U-Boot (and in particular the md command) uses
|
effective address. It is therefore not necessary to regard
|
U-Boot address as virtual addresses that need to be translated
|
to physical addresses. However, sandbox requires this, since
|
it maintains its own little RAM buffer which contains all
|
addressable memory. This option causes some memory accesses
|
to be mapped through map_sysmem() / unmap_sysmem().
|
|
- CONFIG_X86_RESET_VECTOR
|
If defined, the x86 reset vector code is included. This is not
|
needed when U-Boot is running from Coreboot.
|
|
- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC:
|
Enables the RTC32K OSC on AM33xx based plattforms
|
|
- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
|
Option to disable subpage write in NAND driver
|
driver that uses this:
|
drivers/mtd/nand/raw/davinci_nand.c
|
|
Freescale QE/FMAN Firmware Support:
|
-----------------------------------
|
|
The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
|
loading of "firmware", which is encoded in the QE firmware binary format.
|
This firmware often needs to be loaded during U-Boot booting, so macros
|
are used to identify the storage device (NOR flash, SPI, etc) and the address
|
within that device.
|
|
- CONFIG_SYS_FMAN_FW_ADDR
|
The address in the storage device where the FMAN microcode is located. The
|
meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
|
is also specified.
|
|
- CONFIG_SYS_QE_FW_ADDR
|
The address in the storage device where the QE microcode is located. The
|
meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
|
is also specified.
|
|
- CONFIG_SYS_QE_FMAN_FW_LENGTH
|
The maximum possible size of the firmware. The firmware binary format
|
has a field that specifies the actual size of the firmware, but it
|
might not be possible to read any part of the firmware unless some
|
local storage is allocated to hold the entire firmware first.
|
|
- CONFIG_SYS_QE_FMAN_FW_IN_NOR
|
Specifies that QE/FMAN firmware is located in NOR flash, mapped as
|
normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
|
virtual address in NOR flash.
|
|
- CONFIG_SYS_QE_FMAN_FW_IN_NAND
|
Specifies that QE/FMAN firmware is located in NAND flash.
|
CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
|
|
- CONFIG_SYS_QE_FMAN_FW_IN_MMC
|
Specifies that QE/FMAN firmware is located on the primary SD/MMC
|
device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
|
|
- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
|
Specifies that QE/FMAN firmware is located in the remote (master)
|
memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
|
can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
|
window->master inbound window->master LAW->the ucode address in
|
master's memory space.
|
|
Freescale Layerscape Management Complex Firmware Support:
|
---------------------------------------------------------
|
The Freescale Layerscape Management Complex (MC) supports the loading of
|
"firmware".
|
This firmware often needs to be loaded during U-Boot booting, so macros
|
are used to identify the storage device (NOR flash, SPI, etc) and the address
|
within that device.
|
|
- CONFIG_FSL_MC_ENET
|
Enable the MC driver for Layerscape SoCs.
|
|
Freescale Layerscape Debug Server Support:
|
-------------------------------------------
|
The Freescale Layerscape Debug Server Support supports the loading of
|
"Debug Server firmware" and triggering SP boot-rom.
|
This firmware often needs to be loaded during U-Boot booting.
|
|
- CONFIG_SYS_MC_RSV_MEM_ALIGN
|
Define alignment of reserved memory MC requires
|
|
Reproducible builds
|
-------------------
|
|
In order to achieve reproducible builds, timestamps used in the U-Boot build
|
process have to be set to a fixed value.
|
|
This is done using the SOURCE_DATE_EPOCH environment variable.
|
SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
|
option for U-Boot or an environment variable in U-Boot.
|
|
SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
|
|
Building the Software:
|
======================
|
|
Building U-Boot has been tested in several native build environments
|
and in many different cross environments. Of course we cannot support
|
all possibly existing versions of cross development tools in all
|
(potentially obsolete) versions. In case of tool chain problems we
|
recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
|
which is extensively used to build and test U-Boot.
|
|
If you are not using a native environment, it is assumed that you
|
have GNU cross compiling tools available in your path. In this case,
|
you must set the environment variable CROSS_COMPILE in your shell.
|
Note that no changes to the Makefile or any other source files are
|
necessary. For example using the ELDK on a 4xx CPU, please enter:
|
|
$ CROSS_COMPILE=ppc_4xx-
|
$ export CROSS_COMPILE
|
|
Note: If you wish to generate Windows versions of the utilities in
|
the tools directory you can use the MinGW toolchain
|
(http://www.mingw.org). Set your HOST tools to the MinGW
|
toolchain and execute 'make tools'. For example:
|
|
$ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
|
|
Binaries such as tools/mkimage.exe will be created which can
|
be executed on computers running Windows.
|
|
U-Boot is intended to be simple to build. After installing the
|
sources you must configure U-Boot for one specific board type. This
|
is done by typing:
|
|
make NAME_defconfig
|
|
where "NAME_defconfig" is the name of one of the existing configu-
|
rations; see boards.cfg for supported names.
|
|
Note: for some board special configuration names may exist; check if
|
additional information is available from the board vendor; for
|
instance, the TQM823L systems are available without (standard)
|
or with LCD support. You can select such additional "features"
|
when choosing the configuration, i. e.
|
|
make TQM823L_defconfig
|
- will configure for a plain TQM823L, i. e. no LCD support
|
|
make TQM823L_LCD_defconfig
|
- will configure for a TQM823L with U-Boot console on LCD
|
|
etc.
|
|
|
Finally, type "make all", and you should get some working U-Boot
|
images ready for download to / installation on your system:
|
|
- "u-boot.bin" is a raw binary image
|
- "u-boot" is an image in ELF binary format
|
- "u-boot.srec" is in Motorola S-Record format
|
|
By default the build is performed locally and the objects are saved
|
in the source directory. One of the two methods can be used to change
|
this behavior and build U-Boot to some external directory:
|
|
1. Add O= to the make command line invocations:
|
|
make O=/tmp/build distclean
|
make O=/tmp/build NAME_defconfig
|
make O=/tmp/build all
|
|
2. Set environment variable KBUILD_OUTPUT to point to the desired location:
|
|
export KBUILD_OUTPUT=/tmp/build
|
make distclean
|
make NAME_defconfig
|
make all
|
|
Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
|
variable.
|
|
|
Please be aware that the Makefiles assume you are using GNU make, so
|
for instance on NetBSD you might need to use "gmake" instead of
|
native "make".
|
|
|
If the system board that you have is not listed, then you will need
|
to port U-Boot to your hardware platform. To do this, follow these
|
steps:
|
|
1. Create a new directory to hold your board specific code. Add any
|
files you need. In your board directory, you will need at least
|
the "Makefile" and a "<board>.c".
|
2. Create a new configuration file "include/configs/<board>.h" for
|
your board.
|
3. If you're porting U-Boot to a new CPU, then also create a new
|
directory to hold your CPU specific code. Add any files you need.
|
4. Run "make <board>_defconfig" with your new name.
|
5. Type "make", and you should get a working "u-boot.srec" file
|
to be installed on your target system.
|
6. Debug and solve any problems that might arise.
|
[Of course, this last step is much harder than it sounds.]
|
|
|
Testing of U-Boot Modifications, Ports to New Hardware, etc.:
|
==============================================================
|
|
If you have modified U-Boot sources (for instance added a new board
|
or support for new devices, a new CPU, etc.) you are expected to
|
provide feedback to the other developers. The feedback normally takes
|
the form of a "patch", i. e. a context diff against a certain (latest
|
official or latest in the git repository) version of U-Boot sources.
|
|
But before you submit such a patch, please verify that your modifi-
|
cation did not break existing code. At least make sure that *ALL* of
|
the supported boards compile WITHOUT ANY compiler warnings. To do so,
|
just run the buildman script (tools/buildman/buildman), which will
|
configure and build U-Boot for ALL supported system. Be warned, this
|
will take a while. Please see the buildman README, or run 'buildman -H'
|
for documentation.
|
|
|
See also "U-Boot Porting Guide" below.
|
|
|
Monitor Commands - Overview:
|
============================
|
|
go - start application at address 'addr'
|
run - run commands in an environment variable
|
bootm - boot application image from memory
|
bootp - boot image via network using BootP/TFTP protocol
|
bootz - boot zImage from memory
|
tftpboot- boot image via network using TFTP protocol
|
and env variables "ipaddr" and "serverip"
|
(and eventually "gatewayip")
|
tftpput - upload a file via network using TFTP protocol
|
rarpboot- boot image via network using RARP/TFTP protocol
|
diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
|
loads - load S-Record file over serial line
|
loadb - load binary file over serial line (kermit mode)
|
md - memory display
|
mm - memory modify (auto-incrementing)
|
nm - memory modify (constant address)
|
mw - memory write (fill)
|
cp - memory copy
|
cmp - memory compare
|
crc32 - checksum calculation
|
i2c - I2C sub-system
|
sspi - SPI utility commands
|
base - print or set address offset
|
printenv- print environment variables
|
setenv - set environment variables
|
saveenv - save environment variables to persistent storage
|
protect - enable or disable FLASH write protection
|
erase - erase FLASH memory
|
flinfo - print FLASH memory information
|
nand - NAND memory operations (see doc/README.nand)
|
bdinfo - print Board Info structure
|
iminfo - print header information for application image
|
coninfo - print console devices and informations
|
ide - IDE sub-system
|
loop - infinite loop on address range
|
loopw - infinite write loop on address range
|
mtest - simple RAM test
|
icache - enable or disable instruction cache
|
dcache - enable or disable data cache
|
reset - Perform RESET of the CPU
|
echo - echo args to console
|
version - print monitor version
|
help - print online help
|
? - alias for 'help'
|
|
|
Monitor Commands - Detailed Description:
|
========================================
|
|
TODO.
|
|
For now: just type "help <command>".
|
|
|
Environment Variables:
|
======================
|
|
U-Boot supports user configuration using Environment Variables which
|
can be made persistent by saving to Flash memory.
|
|
Environment Variables are set using "setenv", printed using
|
"printenv", and saved to Flash using "saveenv". Using "setenv"
|
without a value can be used to delete a variable from the
|
environment. As long as you don't save the environment you are
|
working with an in-memory copy. In case the Flash area containing the
|
environment is erased by accident, a default environment is provided.
|
|
Some configuration options can be set using Environment Variables.
|
|
List of environment variables (most likely not complete):
|
|
baudrate - see CONFIG_BAUDRATE
|
|
bootdelay - see CONFIG_BOOTDELAY
|
|
bootcmd - see CONFIG_BOOTCOMMAND
|
|
bootargs - Boot arguments when booting an RTOS image
|
|
bootfile - Name of the image to load with TFTP
|
|
bootm_low - Memory range available for image processing in the bootm
|
command can be restricted. This variable is given as
|
a hexadecimal number and defines lowest address allowed
|
for use by the bootm command. See also "bootm_size"
|
environment variable. Address defined by "bootm_low" is
|
also the base of the initial memory mapping for the Linux
|
kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
|
bootm_mapsize.
|
|
bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
|
This variable is given as a hexadecimal number and it
|
defines the size of the memory region starting at base
|
address bootm_low that is accessible by the Linux kernel
|
during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
|
as the default value if it is defined, and bootm_size is
|
used otherwise.
|
|
bootm_size - Memory range available for image processing in the bootm
|
command can be restricted. This variable is given as
|
a hexadecimal number and defines the size of the region
|
allowed for use by the bootm command. See also "bootm_low"
|
environment variable.
|
|
updatefile - Location of the software update file on a TFTP server, used
|
by the automatic software update feature. Please refer to
|
documentation in doc/README.update for more details.
|
|
autoload - if set to "no" (any string beginning with 'n'),
|
"bootp" will just load perform a lookup of the
|
configuration from the BOOTP server, but not try to
|
load any image using TFTP
|
|
autostart - if set to "yes", an image loaded using the "bootp",
|
"rarpboot", "tftpboot" or "diskboot" commands will
|
be automatically started (by internally calling
|
"bootm")
|
|
If set to "no", a standalone image passed to the
|
"bootm" command will be copied to the load address
|
(and eventually uncompressed), but NOT be started.
|
This can be used to load and uncompress arbitrary
|
data.
|
|
fdt_high - if set this restricts the maximum address that the
|
flattened device tree will be copied into upon boot.
|
For example, if you have a system with 1 GB memory
|
at physical address 0x10000000, while Linux kernel
|
only recognizes the first 704 MB as low memory, you
|
may need to set fdt_high as 0x3C000000 to have the
|
device tree blob be copied to the maximum address
|
of the 704 MB low memory, so that Linux kernel can
|
access it during the boot procedure.
|
|
If this is set to the special value 0xFFFFFFFF then
|
the fdt will not be copied at all on boot. For this
|
to work it must reside in writable memory, have
|
sufficient padding on the end of it for u-boot to
|
add the information it needs into it, and the memory
|
must be accessible by the kernel.
|
|
fdtcontroladdr- if set this is the address of the control flattened
|
device tree used by U-Boot when CONFIG_OF_CONTROL is
|
defined.
|
|
i2cfast - (PPC405GP|PPC405EP only)
|
if set to 'y' configures Linux I2C driver for fast
|
mode (400kHZ). This environment variable is used in
|
initialization code. So, for changes to be effective
|
it must be saved and board must be reset.
|
|
initrd_high - restrict positioning of initrd images:
|
If this variable is not set, initrd images will be
|
copied to the highest possible address in RAM; this
|
is usually what you want since it allows for
|
maximum initrd size. If for some reason you want to
|
make sure that the initrd image is loaded below the
|
CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
|
variable to a value of "no" or "off" or "0".
|
Alternatively, you can set it to a maximum upper
|
address to use (U-Boot will still check that it
|
does not overwrite the U-Boot stack and data).
|
|
For instance, when you have a system with 16 MB
|
RAM, and want to reserve 4 MB from use by Linux,
|
you can do this by adding "mem=12M" to the value of
|
the "bootargs" variable. However, now you must make
|
sure that the initrd image is placed in the first
|
12 MB as well - this can be done with
|
|
setenv initrd_high 00c00000
|
|
If you set initrd_high to 0xFFFFFFFF, this is an
|
indication to U-Boot that all addresses are legal
|
for the Linux kernel, including addresses in flash
|
memory. In this case U-Boot will NOT COPY the
|
ramdisk at all. This may be useful to reduce the
|
boot time on your system, but requires that this
|
feature is supported by your Linux kernel.
|
|
ipaddr - IP address; needed for tftpboot command
|
|
loadaddr - Default load address for commands like "bootp",
|
"rarpboot", "tftpboot", "loadb" or "diskboot"
|
|
loads_echo - see CONFIG_LOADS_ECHO
|
|
serverip - TFTP server IP address; needed for tftpboot command
|
|
bootretry - see CONFIG_BOOT_RETRY_TIME
|
|
bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
|
|
bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
|
|
ethprime - controls which interface is used first.
|
|
ethact - controls which interface is currently active.
|
For example you can do the following
|
|
=> setenv ethact FEC
|
=> ping 192.168.0.1 # traffic sent on FEC
|
=> setenv ethact SCC
|
=> ping 10.0.0.1 # traffic sent on SCC
|
|
ethrotate - When set to "no" U-Boot does not go through all
|
available network interfaces.
|
It just stays at the currently selected interface.
|
|
netretry - When set to "no" each network operation will
|
either succeed or fail without retrying.
|
When set to "once" the network operation will
|
fail when all the available network interfaces
|
are tried once without success.
|
Useful on scripts which control the retry operation
|
themselves.
|
|
npe_ucode - set load address for the NPE microcode
|
|
silent_linux - If set then Linux will be told to boot silently, by
|
changing the console to be empty. If "yes" it will be
|
made silent. If "no" it will not be made silent. If
|
unset, then it will be made silent if the U-Boot console
|
is silent.
|
|
tftpsrcp - If this is set, the value is used for TFTP's
|
UDP source port.
|
|
tftpdstp - If this is set, the value is used for TFTP's UDP
|
destination port instead of the Well Know Port 69.
|
|
tftpblocksize - Block size to use for TFTP transfers; if not set,
|
we use the TFTP server's default block size
|
|
tftptimeout - Retransmission timeout for TFTP packets (in milli-
|
seconds, minimum value is 1000 = 1 second). Defines
|
when a packet is considered to be lost so it has to
|
be retransmitted. The default is 5000 = 5 seconds.
|
Lowering this value may make downloads succeed
|
faster in networks with high packet loss rates or
|
with unreliable TFTP servers.
|
|
tftptimeoutcountmax - maximum count of TFTP timeouts (no
|
unit, minimum value = 0). Defines how many timeouts
|
can happen during a single file transfer before that
|
transfer is aborted. The default is 10, and 0 means
|
'no timeouts allowed'. Increasing this value may help
|
downloads succeed with high packet loss rates, or with
|
unreliable TFTP servers or client hardware.
|
|
vlan - When set to a value < 4095 the traffic over
|
Ethernet is encapsulated/received over 802.1q
|
VLAN tagged frames.
|
|
bootpretryperiod - Period during which BOOTP/DHCP sends retries.
|
Unsigned value, in milliseconds. If not set, the period will
|
be either the default (28000), or a value based on
|
CONFIG_NET_RETRY_COUNT, if defined. This value has
|
precedence over the valu based on CONFIG_NET_RETRY_COUNT.
|
|
The following image location variables contain the location of images
|
used in booting. The "Image" column gives the role of the image and is
|
not an environment variable name. The other columns are environment
|
variable names. "File Name" gives the name of the file on a TFTP
|
server, "RAM Address" gives the location in RAM the image will be
|
loaded to, and "Flash Location" gives the image's address in NOR
|
flash or offset in NAND flash.
|
|
*Note* - these variables don't have to be defined for all boards, some
|
boards currently use other variables for these purposes, and some
|
boards use these variables for other purposes.
|
|
Image File Name RAM Address Flash Location
|
----- --------- ----------- --------------
|
u-boot u-boot u-boot_addr_r u-boot_addr
|
Linux kernel bootfile kernel_addr_r kernel_addr
|
device tree blob fdtfile fdt_addr_r fdt_addr
|
ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
|
|
The following environment variables may be used and automatically
|
updated by the network boot commands ("bootp" and "rarpboot"),
|
depending the information provided by your boot server:
|
|
bootfile - see above
|
dnsip - IP address of your Domain Name Server
|
dnsip2 - IP address of your secondary Domain Name Server
|
gatewayip - IP address of the Gateway (Router) to use
|
hostname - Target hostname
|
ipaddr - see above
|
netmask - Subnet Mask
|
rootpath - Pathname of the root filesystem on the NFS server
|
serverip - see above
|
|
|
There are two special Environment Variables:
|
|
serial# - contains hardware identification information such
|
as type string and/or serial number
|
ethaddr - Ethernet address
|
|
These variables can be set only once (usually during manufacturing of
|
the board). U-Boot refuses to delete or overwrite these variables
|
once they have been set once.
|
|
|
Further special Environment Variables:
|
|
ver - Contains the U-Boot version string as printed
|
with the "version" command. This variable is
|
readonly (see CONFIG_VERSION_VARIABLE).
|
|
|
Please note that changes to some configuration parameters may take
|
only effect after the next boot (yes, that's just like Windoze :-).
|
|
|
Callback functions for environment variables:
|
---------------------------------------------
|
|
For some environment variables, the behavior of u-boot needs to change
|
when their values are changed. This functionality allows functions to
|
be associated with arbitrary variables. On creation, overwrite, or
|
deletion, the callback will provide the opportunity for some side
|
effect to happen or for the change to be rejected.
|
|
The callbacks are named and associated with a function using the
|
U_BOOT_ENV_CALLBACK macro in your board or driver code.
|
|
These callbacks are associated with variables in one of two ways. The
|
static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
|
in the board configuration to a string that defines a list of
|
associations. The list must be in the following format:
|
|
entry = variable_name[:callback_name]
|
list = entry[,list]
|
|
If the callback name is not specified, then the callback is deleted.
|
Spaces are also allowed anywhere in the list.
|
|
Callbacks can also be associated by defining the ".callbacks" variable
|
with the same list format above. Any association in ".callbacks" will
|
override any association in the static list. You can define
|
CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
|
".callbacks" environment variable in the default or embedded environment.
|
|
If CONFIG_REGEX is defined, the variable_name above is evaluated as a
|
regular expression. This allows multiple variables to be connected to
|
the same callback without explicitly listing them all out.
|
|
|
Command Line Parsing:
|
=====================
|
|
There are two different command line parsers available with U-Boot:
|
the old "simple" one, and the much more powerful "hush" shell:
|
|
Old, simple command line parser:
|
--------------------------------
|
|
- supports environment variables (through setenv / saveenv commands)
|
- several commands on one line, separated by ';'
|
- variable substitution using "... ${name} ..." syntax
|
- special characters ('$', ';') can be escaped by prefixing with '\',
|
for example:
|
setenv bootcmd bootm \${address}
|
- You can also escape text by enclosing in single apostrophes, for example:
|
setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
|
|
Hush shell:
|
-----------
|
|
- similar to Bourne shell, with control structures like
|
if...then...else...fi, for...do...done; while...do...done,
|
until...do...done, ...
|
- supports environment ("global") variables (through setenv / saveenv
|
commands) and local shell variables (through standard shell syntax
|
"name=value"); only environment variables can be used with "run"
|
command
|
|
General rules:
|
--------------
|
|
(1) If a command line (or an environment variable executed by a "run"
|
command) contains several commands separated by semicolon, and
|
one of these commands fails, then the remaining commands will be
|
executed anyway.
|
|
(2) If you execute several variables with one call to run (i. e.
|
calling run with a list of variables as arguments), any failing
|
command will cause "run" to terminate, i. e. the remaining
|
variables are not executed.
|
|
Note for Redundant Ethernet Interfaces:
|
=======================================
|
|
Some boards come with redundant Ethernet interfaces; U-Boot supports
|
such configurations and is capable of automatic selection of a
|
"working" interface when needed. MAC assignment works as follows:
|
|
Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
|
MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
|
"eth1addr" (=>eth1), "eth2addr", ...
|
|
If the network interface stores some valid MAC address (for instance
|
in SROM), this is used as default address if there is NO correspon-
|
ding setting in the environment; if the corresponding environment
|
variable is set, this overrides the settings in the card; that means:
|
|
o If the SROM has a valid MAC address, and there is no address in the
|
environment, the SROM's address is used.
|
|
o If there is no valid address in the SROM, and a definition in the
|
environment exists, then the value from the environment variable is
|
used.
|
|
o If both the SROM and the environment contain a MAC address, and
|
both addresses are the same, this MAC address is used.
|
|
o If both the SROM and the environment contain a MAC address, and the
|
addresses differ, the value from the environment is used and a
|
warning is printed.
|
|
o If neither SROM nor the environment contain a MAC address, an error
|
is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
|
a random, locally-assigned MAC is used.
|
|
If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
|
will be programmed into hardware as part of the initialization process. This
|
may be skipped by setting the appropriate 'ethmacskip' environment variable.
|
The naming convention is as follows:
|
"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
|
|
Image Formats:
|
==============
|
|
U-Boot is capable of booting (and performing other auxiliary operations on)
|
images in two formats:
|
|
New uImage format (FIT)
|
-----------------------
|
|
Flexible and powerful format based on Flattened Image Tree -- FIT (similar
|
to Flattened Device Tree). It allows the use of images with multiple
|
components (several kernels, ramdisks, etc.), with contents protected by
|
SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
|
|
|
Old uImage format
|
-----------------
|
|
Old image format is based on binary files which can be basically anything,
|
preceded by a special header; see the definitions in include/image.h for
|
details; basically, the header defines the following image properties:
|
|
* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
|
4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
|
LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
|
Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
|
INTEGRITY).
|
* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
|
IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
|
Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
|
* Compression Type (uncompressed, gzip, bzip2)
|
* Load Address
|
* Entry Point
|
* Image Name
|
* Image Timestamp
|
|
The header is marked by a special Magic Number, and both the header
|
and the data portions of the image are secured against corruption by
|
CRC32 checksums.
|
|
|
Linux Support:
|
==============
|
|
Although U-Boot should support any OS or standalone application
|
easily, the main focus has always been on Linux during the design of
|
U-Boot.
|
|
U-Boot includes many features that so far have been part of some
|
special "boot loader" code within the Linux kernel. Also, any
|
"initrd" images to be used are no longer part of one big Linux image;
|
instead, kernel and "initrd" are separate images. This implementation
|
serves several purposes:
|
|
- the same features can be used for other OS or standalone
|
applications (for instance: using compressed images to reduce the
|
Flash memory footprint)
|
|
- it becomes much easier to port new Linux kernel versions because
|
lots of low-level, hardware dependent stuff are done by U-Boot
|
|
- the same Linux kernel image can now be used with different "initrd"
|
images; of course this also means that different kernel images can
|
be run with the same "initrd". This makes testing easier (you don't
|
have to build a new "zImage.initrd" Linux image when you just
|
change a file in your "initrd"). Also, a field-upgrade of the
|
software is easier now.
|
|
|
Linux HOWTO:
|
============
|
|
Porting Linux to U-Boot based systems:
|
---------------------------------------
|
|
U-Boot cannot save you from doing all the necessary modifications to
|
configure the Linux device drivers for use with your target hardware
|
(no, we don't intend to provide a full virtual machine interface to
|
Linux :-).
|
|
But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
|
|
Just make sure your machine specific header file (for instance
|
include/asm-ppc/tqm8xx.h) includes the same definition of the Board
|
Information structure as we define in include/asm-<arch>/u-boot.h,
|
and make sure that your definition of IMAP_ADDR uses the same value
|
as your U-Boot configuration in CONFIG_SYS_IMMR.
|
|
Note that U-Boot now has a driver model, a unified model for drivers.
|
If you are adding a new driver, plumb it into driver model. If there
|
is no uclass available, you are encouraged to create one. See
|
doc/driver-model.
|
|
|
Configuring the Linux kernel:
|
-----------------------------
|
|
No specific requirements for U-Boot. Make sure you have some root
|
device (initial ramdisk, NFS) for your target system.
|
|
|
Building a Linux Image:
|
-----------------------
|
|
With U-Boot, "normal" build targets like "zImage" or "bzImage" are
|
not used. If you use recent kernel source, a new build target
|
"uImage" will exist which automatically builds an image usable by
|
U-Boot. Most older kernels also have support for a "pImage" target,
|
which was introduced for our predecessor project PPCBoot and uses a
|
100% compatible format.
|
|
Example:
|
|
make TQM850L_defconfig
|
make oldconfig
|
make dep
|
make uImage
|
|
The "uImage" build target uses a special tool (in 'tools/mkimage') to
|
encapsulate a compressed Linux kernel image with header information,
|
CRC32 checksum etc. for use with U-Boot. This is what we are doing:
|
|
* build a standard "vmlinux" kernel image (in ELF binary format):
|
|
* convert the kernel into a raw binary image:
|
|
${CROSS_COMPILE}-objcopy -O binary \
|
-R .note -R .comment \
|
-S vmlinux linux.bin
|
|
* compress the binary image:
|
|
gzip -9 linux.bin
|
|
* package compressed binary image for U-Boot:
|
|
mkimage -A ppc -O linux -T kernel -C gzip \
|
-a 0 -e 0 -n "Linux Kernel Image" \
|
-d linux.bin.gz uImage
|
|
|
The "mkimage" tool can also be used to create ramdisk images for use
|
with U-Boot, either separated from the Linux kernel image, or
|
combined into one file. "mkimage" encapsulates the images with a 64
|
byte header containing information about target architecture,
|
operating system, image type, compression method, entry points, time
|
stamp, CRC32 checksums, etc.
|
|
"mkimage" can be called in two ways: to verify existing images and
|
print the header information, or to build new images.
|
|
In the first form (with "-l" option) mkimage lists the information
|
contained in the header of an existing U-Boot image; this includes
|
checksum verification:
|
|
tools/mkimage -l image
|
-l ==> list image header information
|
|
The second form (with "-d" option) is used to build a U-Boot image
|
from a "data file" which is used as image payload:
|
|
tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
|
-n name -d data_file image
|
-A ==> set architecture to 'arch'
|
-O ==> set operating system to 'os'
|
-T ==> set image type to 'type'
|
-C ==> set compression type 'comp'
|
-a ==> set load address to 'addr' (hex)
|
-e ==> set entry point to 'ep' (hex)
|
-n ==> set image name to 'name'
|
-d ==> use image data from 'datafile'
|
|
Right now, all Linux kernels for PowerPC systems use the same load
|
address (0x00000000), but the entry point address depends on the
|
kernel version:
|
|
- 2.2.x kernels have the entry point at 0x0000000C,
|
- 2.3.x and later kernels have the entry point at 0x00000000.
|
|
So a typical call to build a U-Boot image would read:
|
|
-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
|
> -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
|
> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
|
> examples/uImage.TQM850L
|
Image Name: 2.4.4 kernel for TQM850L
|
Created: Wed Jul 19 02:34:59 2000
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
|
Load Address: 0x00000000
|
Entry Point: 0x00000000
|
|
To verify the contents of the image (or check for corruption):
|
|
-> tools/mkimage -l examples/uImage.TQM850L
|
Image Name: 2.4.4 kernel for TQM850L
|
Created: Wed Jul 19 02:34:59 2000
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
|
Load Address: 0x00000000
|
Entry Point: 0x00000000
|
|
NOTE: for embedded systems where boot time is critical you can trade
|
speed for memory and install an UNCOMPRESSED image instead: this
|
needs more space in Flash, but boots much faster since it does not
|
need to be uncompressed:
|
|
-> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
|
-> tools/mkimage -n '2.4.4 kernel for TQM850L' \
|
> -A ppc -O linux -T kernel -C none -a 0 -e 0 \
|
> -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
|
> examples/uImage.TQM850L-uncompressed
|
Image Name: 2.4.4 kernel for TQM850L
|
Created: Wed Jul 19 02:34:59 2000
|
Image Type: PowerPC Linux Kernel Image (uncompressed)
|
Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
|
Load Address: 0x00000000
|
Entry Point: 0x00000000
|
|
|
Similar you can build U-Boot images from a 'ramdisk.image.gz' file
|
when your kernel is intended to use an initial ramdisk:
|
|
-> tools/mkimage -n 'Simple Ramdisk Image' \
|
> -A ppc -O linux -T ramdisk -C gzip \
|
> -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
|
Image Name: Simple Ramdisk Image
|
Created: Wed Jan 12 14:01:50 2000
|
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
|
Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
|
Load Address: 0x00000000
|
Entry Point: 0x00000000
|
|
The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
|
option performs the converse operation of the mkimage's second form (the "-d"
|
option). Given an image built by mkimage, the dumpimage extracts a "data file"
|
from the image:
|
|
tools/dumpimage -i image -T type -p position data_file
|
-i ==> extract from the 'image' a specific 'data_file'
|
-T ==> set image type to 'type'
|
-p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
|
|
|
Installing a Linux Image:
|
-------------------------
|
|
To downloading a U-Boot image over the serial (console) interface,
|
you must convert the image to S-Record format:
|
|
objcopy -I binary -O srec examples/image examples/image.srec
|
|
The 'objcopy' does not understand the information in the U-Boot
|
image header, so the resulting S-Record file will be relative to
|
address 0x00000000. To load it to a given address, you need to
|
specify the target address as 'offset' parameter with the 'loads'
|
command.
|
|
Example: install the image to address 0x40100000 (which on the
|
TQM8xxL is in the first Flash bank):
|
|
=> erase 40100000 401FFFFF
|
|
.......... done
|
Erased 8 sectors
|
|
=> loads 40100000
|
## Ready for S-Record download ...
|
~>examples/image.srec
|
1 2 3 4 5 6 7 8 9 10 11 12 13 ...
|
...
|
15989 15990 15991 15992
|
[file transfer complete]
|
[connected]
|
## Start Addr = 0x00000000
|
|
|
You can check the success of the download using the 'iminfo' command;
|
this includes a checksum verification so you can be sure no data
|
corruption happened:
|
|
=> imi 40100000
|
|
## Checking Image at 40100000 ...
|
Image Name: 2.2.13 for initrd on TQM850L
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 335725 Bytes = 327 kB = 0 MB
|
Load Address: 00000000
|
Entry Point: 0000000c
|
Verifying Checksum ... OK
|
|
|
Boot Linux:
|
-----------
|
|
The "bootm" command is used to boot an application that is stored in
|
memory (RAM or Flash). In case of a Linux kernel image, the contents
|
of the "bootargs" environment variable is passed to the kernel as
|
parameters. You can check and modify this variable using the
|
"printenv" and "setenv" commands:
|
|
|
=> printenv bootargs
|
bootargs=root=/dev/ram
|
|
=> setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
|
|
=> printenv bootargs
|
bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
|
|
=> bootm 40020000
|
## Booting Linux kernel at 40020000 ...
|
Image Name: 2.2.13 for NFS on TQM850L
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 381681 Bytes = 372 kB = 0 MB
|
Load Address: 00000000
|
Entry Point: 0000000c
|
Verifying Checksum ... OK
|
Uncompressing Kernel Image ... OK
|
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
|
Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
|
time_init: decrementer frequency = 187500000/60
|
Calibrating delay loop... 49.77 BogoMIPS
|
Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
|
...
|
|
If you want to boot a Linux kernel with initial RAM disk, you pass
|
the memory addresses of both the kernel and the initrd image (PPBCOOT
|
format!) to the "bootm" command:
|
|
=> imi 40100000 40200000
|
|
## Checking Image at 40100000 ...
|
Image Name: 2.2.13 for initrd on TQM850L
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 335725 Bytes = 327 kB = 0 MB
|
Load Address: 00000000
|
Entry Point: 0000000c
|
Verifying Checksum ... OK
|
|
## Checking Image at 40200000 ...
|
Image Name: Simple Ramdisk Image
|
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
|
Data Size: 566530 Bytes = 553 kB = 0 MB
|
Load Address: 00000000
|
Entry Point: 00000000
|
Verifying Checksum ... OK
|
|
=> bootm 40100000 40200000
|
## Booting Linux kernel at 40100000 ...
|
Image Name: 2.2.13 for initrd on TQM850L
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 335725 Bytes = 327 kB = 0 MB
|
Load Address: 00000000
|
Entry Point: 0000000c
|
Verifying Checksum ... OK
|
Uncompressing Kernel Image ... OK
|
## Loading RAMDisk Image at 40200000 ...
|
Image Name: Simple Ramdisk Image
|
Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
|
Data Size: 566530 Bytes = 553 kB = 0 MB
|
Load Address: 00000000
|
Entry Point: 00000000
|
Verifying Checksum ... OK
|
Loading Ramdisk ... OK
|
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
|
Boot arguments: root=/dev/ram
|
time_init: decrementer frequency = 187500000/60
|
Calibrating delay loop... 49.77 BogoMIPS
|
...
|
RAMDISK: Compressed image found at block 0
|
VFS: Mounted root (ext2 filesystem).
|
|
bash#
|
|
Boot Linux and pass a flat device tree:
|
-----------
|
|
First, U-Boot must be compiled with the appropriate defines. See the section
|
titled "Linux Kernel Interface" above for a more in depth explanation. The
|
following is an example of how to start a kernel and pass an updated
|
flat device tree:
|
|
=> print oftaddr
|
oftaddr=0x300000
|
=> print oft
|
oft=oftrees/mpc8540ads.dtb
|
=> tftp $oftaddr $oft
|
Speed: 1000, full duplex
|
Using TSEC0 device
|
TFTP from server 192.168.1.1; our IP address is 192.168.1.101
|
Filename 'oftrees/mpc8540ads.dtb'.
|
Load address: 0x300000
|
Loading: #
|
done
|
Bytes transferred = 4106 (100a hex)
|
=> tftp $loadaddr $bootfile
|
Speed: 1000, full duplex
|
Using TSEC0 device
|
TFTP from server 192.168.1.1; our IP address is 192.168.1.2
|
Filename 'uImage'.
|
Load address: 0x200000
|
Loading:############
|
done
|
Bytes transferred = 1029407 (fb51f hex)
|
=> print loadaddr
|
loadaddr=200000
|
=> print oftaddr
|
oftaddr=0x300000
|
=> bootm $loadaddr - $oftaddr
|
## Booting image at 00200000 ...
|
Image Name: Linux-2.6.17-dirty
|
Image Type: PowerPC Linux Kernel Image (gzip compressed)
|
Data Size: 1029343 Bytes = 1005.2 kB
|
Load Address: 00000000
|
Entry Point: 00000000
|
Verifying Checksum ... OK
|
Uncompressing Kernel Image ... OK
|
Booting using flat device tree at 0x300000
|
Using MPC85xx ADS machine description
|
Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
|
[snip]
|
|
|
More About U-Boot Image Types:
|
------------------------------
|
|
U-Boot supports the following image types:
|
|
"Standalone Programs" are directly runnable in the environment
|
provided by U-Boot; it is expected that (if they behave
|
well) you can continue to work in U-Boot after return from
|
the Standalone Program.
|
"OS Kernel Images" are usually images of some Embedded OS which
|
will take over control completely. Usually these programs
|
will install their own set of exception handlers, device
|
drivers, set up the MMU, etc. - this means, that you cannot
|
expect to re-enter U-Boot except by resetting the CPU.
|
"RAMDisk Images" are more or less just data blocks, and their
|
parameters (address, size) are passed to an OS kernel that is
|
being started.
|
"Multi-File Images" contain several images, typically an OS
|
(Linux) kernel image and one or more data images like
|
RAMDisks. This construct is useful for instance when you want
|
to boot over the network using BOOTP etc., where the boot
|
server provides just a single image file, but you want to get
|
for instance an OS kernel and a RAMDisk image.
|
|
"Multi-File Images" start with a list of image sizes, each
|
image size (in bytes) specified by an "uint32_t" in network
|
byte order. This list is terminated by an "(uint32_t)0".
|
Immediately after the terminating 0 follow the images, one by
|
one, all aligned on "uint32_t" boundaries (size rounded up to
|
a multiple of 4 bytes).
|
|
"Firmware Images" are binary images containing firmware (like
|
U-Boot or FPGA images) which usually will be programmed to
|
flash memory.
|
|
"Script files" are command sequences that will be executed by
|
U-Boot's command interpreter; this feature is especially
|
useful when you configure U-Boot to use a real shell (hush)
|
as command interpreter.
|
|
Booting the Linux zImage:
|
-------------------------
|
|
On some platforms, it's possible to boot Linux zImage. This is done
|
using the "bootz" command. The syntax of "bootz" command is the same
|
as the syntax of "bootm" command.
|
|
Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
|
kernel with raw initrd images. The syntax is slightly different, the
|
address of the initrd must be augmented by it's size, in the following
|
format: "<initrd addres>:<initrd size>".
|
|
|
Standalone HOWTO:
|
=================
|
|
One of the features of U-Boot is that you can dynamically load and
|
run "standalone" applications, which can use some resources of
|
U-Boot like console I/O functions or interrupt services.
|
|
Two simple examples are included with the sources:
|
|
"Hello World" Demo:
|
-------------------
|
|
'examples/hello_world.c' contains a small "Hello World" Demo
|
application; it is automatically compiled when you build U-Boot.
|
It's configured to run at address 0x00040004, so you can play with it
|
like that:
|
|
=> loads
|
## Ready for S-Record download ...
|
~>examples/hello_world.srec
|
1 2 3 4 5 6 7 8 9 10 11 ...
|
[file transfer complete]
|
[connected]
|
## Start Addr = 0x00040004
|
|
=> go 40004 Hello World! This is a test.
|
## Starting application at 0x00040004 ...
|
Hello World
|
argc = 7
|
argv[0] = "40004"
|
argv[1] = "Hello"
|
argv[2] = "World!"
|
argv[3] = "This"
|
argv[4] = "is"
|
argv[5] = "a"
|
argv[6] = "test."
|
argv[7] = "<NULL>"
|
Hit any key to exit ...
|
|
## Application terminated, rc = 0x0
|
|
Another example, which demonstrates how to register a CPM interrupt
|
handler with the U-Boot code, can be found in 'examples/timer.c'.
|
Here, a CPM timer is set up to generate an interrupt every second.
|
The interrupt service routine is trivial, just printing a '.'
|
character, but this is just a demo program. The application can be
|
controlled by the following keys:
|
|
? - print current values og the CPM Timer registers
|
b - enable interrupts and start timer
|
e - stop timer and disable interrupts
|
q - quit application
|
|
=> loads
|
## Ready for S-Record download ...
|
~>examples/timer.srec
|
1 2 3 4 5 6 7 8 9 10 11 ...
|
[file transfer complete]
|
[connected]
|
## Start Addr = 0x00040004
|
|
=> go 40004
|
## Starting application at 0x00040004 ...
|
TIMERS=0xfff00980
|
Using timer 1
|
tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
|
|
Hit 'b':
|
[q, b, e, ?] Set interval 1000000 us
|
Enabling timer
|
Hit '?':
|
[q, b, e, ?] ........
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
|
Hit '?':
|
[q, b, e, ?] .
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
|
Hit '?':
|
[q, b, e, ?] .
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
|
Hit '?':
|
[q, b, e, ?] .
|
tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
|
Hit 'e':
|
[q, b, e, ?] ...Stopping timer
|
Hit 'q':
|
[q, b, e, ?] ## Application terminated, rc = 0x0
|
|
|
Minicom warning:
|
================
|
|
Over time, many people have reported problems when trying to use the
|
"minicom" terminal emulation program for serial download. I (wd)
|
consider minicom to be broken, and recommend not to use it. Under
|
Unix, I recommend to use C-Kermit for general purpose use (and
|
especially for kermit binary protocol download ("loadb" command), and
|
use "cu" for S-Record download ("loads" command). See
|
http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
|
for help with kermit.
|
|
|
Nevertheless, if you absolutely want to use it try adding this
|
configuration to your "File transfer protocols" section:
|
|
Name Program Name U/D FullScr IO-Red. Multi
|
X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
|
Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
|
|
|
NetBSD Notes:
|
=============
|
|
Starting at version 0.9.2, U-Boot supports NetBSD both as host
|
(build U-Boot) and target system (boots NetBSD/mpc8xx).
|
|
Building requires a cross environment; it is known to work on
|
NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
|
need gmake since the Makefiles are not compatible with BSD make).
|
Note that the cross-powerpc package does not install include files;
|
attempting to build U-Boot will fail because <machine/ansi.h> is
|
missing. This file has to be installed and patched manually:
|
|
# cd /usr/pkg/cross/powerpc-netbsd/include
|
# mkdir powerpc
|
# ln -s powerpc machine
|
# cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
|
# ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
|
|
Native builds *don't* work due to incompatibilities between native
|
and U-Boot include files.
|
|
Booting assumes that (the first part of) the image booted is a
|
stage-2 loader which in turn loads and then invokes the kernel
|
proper. Loader sources will eventually appear in the NetBSD source
|
tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
|
meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
|
|
|
Implementation Internals:
|
=========================
|
|
The following is not intended to be a complete description of every
|
implementation detail. However, it should help to understand the
|
inner workings of U-Boot and make it easier to port it to custom
|
hardware.
|
|
|
Initial Stack, Global Data:
|
---------------------------
|
|
The implementation of U-Boot is complicated by the fact that U-Boot
|
starts running out of ROM (flash memory), usually without access to
|
system RAM (because the memory controller is not initialized yet).
|
This means that we don't have writable Data or BSS segments, and BSS
|
is not initialized as zero. To be able to get a C environment working
|
at all, we have to allocate at least a minimal stack. Implementation
|
options for this are defined and restricted by the CPU used: Some CPU
|
models provide on-chip memory (like the IMMR area on MPC8xx and
|
MPC826x processors), on others (parts of) the data cache can be
|
locked as (mis-) used as memory, etc.
|
|
Chris Hallinan posted a good summary of these issues to the
|
U-Boot mailing list:
|
|
Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
|
From: "Chris Hallinan" <clh@net1plus.com>
|
Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
|
...
|
|
Correct me if I'm wrong, folks, but the way I understand it
|
is this: Using DCACHE as initial RAM for Stack, etc, does not
|
require any physical RAM backing up the cache. The cleverness
|
is that the cache is being used as a temporary supply of
|
necessary storage before the SDRAM controller is setup. It's
|
beyond the scope of this list to explain the details, but you
|
can see how this works by studying the cache architecture and
|
operation in the architecture and processor-specific manuals.
|
|
OCM is On Chip Memory, which I believe the 405GP has 4K. It
|
is another option for the system designer to use as an
|
initial stack/RAM area prior to SDRAM being available. Either
|
option should work for you. Using CS 4 should be fine if your
|
board designers haven't used it for something that would
|
cause you grief during the initial boot! It is frequently not
|
used.
|
|
CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
|
with your processor/board/system design. The default value
|
you will find in any recent u-boot distribution in
|
walnut.h should work for you. I'd set it to a value larger
|
than your SDRAM module. If you have a 64MB SDRAM module, set
|
it above 400_0000. Just make sure your board has no resources
|
that are supposed to respond to that address! That code in
|
start.S has been around a while and should work as is when
|
you get the config right.
|
|
-Chris Hallinan
|
DS4.COM, Inc.
|
|
It is essential to remember this, since it has some impact on the C
|
code for the initialization procedures:
|
|
* Initialized global data (data segment) is read-only. Do not attempt
|
to write it.
|
|
* Do not use any uninitialized global data (or implicitly initialized
|
as zero data - BSS segment) at all - this is undefined, initiali-
|
zation is performed later (when relocating to RAM).
|
|
* Stack space is very limited. Avoid big data buffers or things like
|
that.
|
|
Having only the stack as writable memory limits means we cannot use
|
normal global data to share information between the code. But it
|
turned out that the implementation of U-Boot can be greatly
|
simplified by making a global data structure (gd_t) available to all
|
functions. We could pass a pointer to this data as argument to _all_
|
functions, but this would bloat the code. Instead we use a feature of
|
the GCC compiler (Global Register Variables) to share the data: we
|
place a pointer (gd) to the global data into a register which we
|
reserve for this purpose.
|
|
When choosing a register for such a purpose we are restricted by the
|
relevant (E)ABI specifications for the current architecture, and by
|
GCC's implementation.
|
|
For PowerPC, the following registers have specific use:
|
R1: stack pointer
|
R2: reserved for system use
|
R3-R4: parameter passing and return values
|
R5-R10: parameter passing
|
R13: small data area pointer
|
R30: GOT pointer
|
R31: frame pointer
|
|
(U-Boot also uses R12 as internal GOT pointer. r12
|
is a volatile register so r12 needs to be reset when
|
going back and forth between asm and C)
|
|
==> U-Boot will use R2 to hold a pointer to the global data
|
|
Note: on PPC, we could use a static initializer (since the
|
address of the global data structure is known at compile time),
|
but it turned out that reserving a register results in somewhat
|
smaller code - although the code savings are not that big (on
|
average for all boards 752 bytes for the whole U-Boot image,
|
624 text + 127 data).
|
|
On ARM, the following registers are used:
|
|
R0: function argument word/integer result
|
R1-R3: function argument word
|
R9: platform specific
|
R10: stack limit (used only if stack checking is enabled)
|
R11: argument (frame) pointer
|
R12: temporary workspace
|
R13: stack pointer
|
R14: link register
|
R15: program counter
|
|
==> U-Boot will use R9 to hold a pointer to the global data
|
|
Note: on ARM, only R_ARM_RELATIVE relocations are supported.
|
|
On Nios II, the ABI is documented here:
|
http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
|
|
==> U-Boot will use gp to hold a pointer to the global data
|
|
Note: on Nios II, we give "-G0" option to gcc and don't use gp
|
to access small data sections, so gp is free.
|
|
On NDS32, the following registers are used:
|
|
R0-R1: argument/return
|
R2-R5: argument
|
R15: temporary register for assembler
|
R16: trampoline register
|
R28: frame pointer (FP)
|
R29: global pointer (GP)
|
R30: link register (LP)
|
R31: stack pointer (SP)
|
PC: program counter (PC)
|
|
==> U-Boot will use R10 to hold a pointer to the global data
|
|
NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
|
or current versions of GCC may "optimize" the code too much.
|
|
Memory Management:
|
------------------
|
|
U-Boot runs in system state and uses physical addresses, i.e. the
|
MMU is not used either for address mapping nor for memory protection.
|
|
The available memory is mapped to fixed addresses using the memory
|
controller. In this process, a contiguous block is formed for each
|
memory type (Flash, SDRAM, SRAM), even when it consists of several
|
physical memory banks.
|
|
U-Boot is installed in the first 128 kB of the first Flash bank (on
|
TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
|
booting and sizing and initializing DRAM, the code relocates itself
|
to the upper end of DRAM. Immediately below the U-Boot code some
|
memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
|
configuration setting]. Below that, a structure with global Board
|
Info data is placed, followed by the stack (growing downward).
|
|
Additionally, some exception handler code is copied to the low 8 kB
|
of DRAM (0x00000000 ... 0x00001FFF).
|
|
So a typical memory configuration with 16 MB of DRAM could look like
|
this:
|
|
0x0000 0000 Exception Vector code
|
:
|
0x0000 1FFF
|
0x0000 2000 Free for Application Use
|
:
|
:
|
|
:
|
:
|
0x00FB FF20 Monitor Stack (Growing downward)
|
0x00FB FFAC Board Info Data and permanent copy of global data
|
0x00FC 0000 Malloc Arena
|
:
|
0x00FD FFFF
|
0x00FE 0000 RAM Copy of Monitor Code
|
... eventually: LCD or video framebuffer
|
... eventually: pRAM (Protected RAM - unchanged by reset)
|
0x00FF FFFF [End of RAM]
|
|
|
System Initialization:
|
----------------------
|
|
In the reset configuration, U-Boot starts at the reset entry point
|
(on most PowerPC systems at address 0x00000100). Because of the reset
|
configuration for CS0# this is a mirror of the on board Flash memory.
|
To be able to re-map memory U-Boot then jumps to its link address.
|
To be able to implement the initialization code in C, a (small!)
|
initial stack is set up in the internal Dual Ported RAM (in case CPUs
|
which provide such a feature like), or in a locked part of the data
|
cache. After that, U-Boot initializes the CPU core, the caches and
|
the SIU.
|
|
Next, all (potentially) available memory banks are mapped using a
|
preliminary mapping. For example, we put them on 512 MB boundaries
|
(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
|
on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
|
programmed for SDRAM access. Using the temporary configuration, a
|
simple memory test is run that determines the size of the SDRAM
|
banks.
|
|
When there is more than one SDRAM bank, and the banks are of
|
different size, the largest is mapped first. For equal size, the first
|
bank (CS2#) is mapped first. The first mapping is always for address
|
0x00000000, with any additional banks following immediately to create
|
contiguous memory starting from 0.
|
|
Then, the monitor installs itself at the upper end of the SDRAM area
|
and allocates memory for use by malloc() and for the global Board
|
Info data; also, the exception vector code is copied to the low RAM
|
pages, and the final stack is set up.
|
|
Only after this relocation will you have a "normal" C environment;
|
until that you are restricted in several ways, mostly because you are
|
running from ROM, and because the code will have to be relocated to a
|
new address in RAM.
|
|
|
U-Boot Porting Guide:
|
----------------------
|
|
[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
|
list, October 2002]
|
|
|
int main(int argc, char *argv[])
|
{
|
sighandler_t no_more_time;
|
|
signal(SIGALRM, no_more_time);
|
alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
|
|
if (available_money > available_manpower) {
|
Pay consultant to port U-Boot;
|
return 0;
|
}
|
|
Download latest U-Boot source;
|
|
Subscribe to u-boot mailing list;
|
|
if (clueless)
|
email("Hi, I am new to U-Boot, how do I get started?");
|
|
while (learning) {
|
Read the README file in the top level directory;
|
Read http://www.denx.de/twiki/bin/view/DULG/Manual;
|
Read applicable doc/*.README;
|
Read the source, Luke;
|
/* find . -name "*.[chS]" | xargs grep -i <keyword> */
|
}
|
|
if (available_money > toLocalCurrency ($2500))
|
Buy a BDI3000;
|
else
|
Add a lot of aggravation and time;
|
|
if (a similar board exists) { /* hopefully... */
|
cp -a board/<similar> board/<myboard>
|
cp include/configs/<similar>.h include/configs/<myboard>.h
|
} else {
|
Create your own board support subdirectory;
|
Create your own board include/configs/<myboard>.h file;
|
}
|
Edit new board/<myboard> files
|
Edit new include/configs/<myboard>.h
|
|
while (!accepted) {
|
while (!running) {
|
do {
|
Add / modify source code;
|
} until (compiles);
|
Debug;
|
if (clueless)
|
email("Hi, I am having problems...");
|
}
|
Send patch file to the U-Boot email list;
|
if (reasonable critiques)
|
Incorporate improvements from email list code review;
|
else
|
Defend code as written;
|
}
|
|
return 0;
|
}
|
|
void no_more_time (int sig)
|
{
|
hire_a_guru();
|
}
|
|
|
Coding Standards:
|
-----------------
|
|
All contributions to U-Boot should conform to the Linux kernel
|
coding style; see the kernel coding style guide at
|
https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
|
script "scripts/Lindent" in your Linux kernel source directory.
|
|
Source files originating from a different project (for example the
|
MTD subsystem) are generally exempt from these guidelines and are not
|
reformatted to ease subsequent migration to newer versions of those
|
sources.
|
|
Please note that U-Boot is implemented in C (and to some small parts in
|
Assembler); no C++ is used, so please do not use C++ style comments (//)
|
in your code.
|
|
Please also stick to the following formatting rules:
|
- remove any trailing white space
|
- use TAB characters for indentation and vertical alignment, not spaces
|
- make sure NOT to use DOS '\r\n' line feeds
|
- do not add more than 2 consecutive empty lines to source files
|
- do not add trailing empty lines to source files
|
|
Submissions which do not conform to the standards may be returned
|
with a request to reformat the changes.
|
|
|
Submitting Patches:
|
-------------------
|
|
Since the number of patches for U-Boot is growing, we need to
|
establish some rules. Submissions which do not conform to these rules
|
may be rejected, even when they contain important and valuable stuff.
|
|
Please see http://www.denx.de/wiki/U-Boot/Patches for details.
|
|
Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
|
see https://lists.denx.de/listinfo/u-boot
|
|
When you send a patch, please include the following information with
|
it:
|
|
* For bug fixes: a description of the bug and how your patch fixes
|
this bug. Please try to include a way of demonstrating that the
|
patch actually fixes something.
|
|
* For new features: a description of the feature and your
|
implementation.
|
|
* A CHANGELOG entry as plaintext (separate from the patch)
|
|
* For major contributions, add a MAINTAINERS file with your
|
information and associated file and directory references.
|
|
* When you add support for a new board, don't forget to add a
|
maintainer e-mail address to the boards.cfg file, too.
|
|
* If your patch adds new configuration options, don't forget to
|
document these in the README file.
|
|
* The patch itself. If you are using git (which is *strongly*
|
recommended) you can easily generate the patch using the
|
"git format-patch". If you then use "git send-email" to send it to
|
the U-Boot mailing list, you will avoid most of the common problems
|
with some other mail clients.
|
|
If you cannot use git, use "diff -purN OLD NEW". If your version of
|
diff does not support these options, then get the latest version of
|
GNU diff.
|
|
The current directory when running this command shall be the parent
|
directory of the U-Boot source tree (i. e. please make sure that
|
your patch includes sufficient directory information for the
|
affected files).
|
|
We prefer patches as plain text. MIME attachments are discouraged,
|
and compressed attachments must not be used.
|
|
* If one logical set of modifications affects or creates several
|
files, all these changes shall be submitted in a SINGLE patch file.
|
|
* Changesets that contain different, unrelated modifications shall be
|
submitted as SEPARATE patches, one patch per changeset.
|
|
|
Notes:
|
|
* Before sending the patch, run the buildman script on your patched
|
source tree and make sure that no errors or warnings are reported
|
for any of the boards.
|
|
* Keep your modifications to the necessary minimum: A patch
|
containing several unrelated changes or arbitrary reformats will be
|
returned with a request to re-formatting / split it.
|
|
* If you modify existing code, make sure that your new code does not
|
add to the memory footprint of the code ;-) Small is beautiful!
|
When adding new features, these should compile conditionally only
|
(using #ifdef), and the resulting code with the new feature
|
disabled must not need more memory than the old code without your
|
modification.
|
|
* Remember that there is a size limit of 100 kB per message on the
|
u-boot mailing list. Bigger patches will be moderated. If they are
|
reasonable and not too big, they will be acknowledged. But patches
|
bigger than the size limit should be avoided.
|
