NVIDIA/u-boot

NVIDIA/u-boot

Description: OpenBMC "Das U-Boot" Source Tree

Language: C

Stars: 2

Forks: 4

Open issues: 0

Created: 2024-05-06T16:48:23Z

Pushed: 2026-09-22T02:02:28Z

Default branch: v2019.04-aspeed-openbmc

Fork: yes

Parent repository: openbmc/u-boot

Archived: no

README:

SPDX-License-Identifier: GPL-2.0+

#

(C) Copyright 2000 - 2013

Wolfgang Denk, DENX Software Engineering, wd@denx.de.

Summary: ========

This directory contains the source code for U-Boot, a boot loader for Embedded boards based on PowerPC, ARM, MIPS and several other processors, which can be installed in a boot ROM and used to initialize and test the hardware or to download and run application code.

The development of U-Boot is closely related to Linux: some parts of the source code originate in the Linux source tree, we have some header files in common, and special provision has been made to support booting of Linux images.

Some attention has been paid to make this software easily configurable and extendable. For instance, all monitor commands are implemented with the same call interface, so that it's very easy to add new commands. Also, instead of permanently adding rarely used code (for instance hardware test utilities) to the monitor, you can load and run it dynamically.

Status: =======

In general, all boards for which a configuration option exists in the Makefile have been tested to some extent and can be considered "working". In fact, many of them are used in production systems.

In case of problems see the CHANGELOG file to find out who contributed the specific port. In addition, there are various MAINTAINERS files scattered throughout the U-Boot source identifying the people or companies responsible for various boards and subsystems.

Note: As of August, 2010, there is no longer a CHANGELOG file in the actual U-Boot source tree; however, it can be created dynamically from the Git log using:

make CHANGELOG

Where to get help: ==================

In case you have questions about, problems with or contributions for U-Boot, you should send a message to the U-Boot mailing list at . There is also an archive of previous traffic on the mailing list - please search the archive before asking FAQ's. Please see http://lists.denx.de/pipermail/u-boot and http://dir.gmane.org/gmane.comp.boot-loaders.u-boot

Where to get source code: =========================

The U-Boot source code is maintained in the Git repository at git://www.denx.de/git/u-boot.git ; you can browse it online at http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary

The "snapshot" links on this page allow you to download tarballs of any version you might be interested in. Official releases are also available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ directory.

Pre-built (and tested) images are available from ftp://ftp.denx.de/pub/u-boot/images/

Where we come from: ===================

• start from 8xxrom sources
• create PPCBoot project (http://sourceforge.net/projects/ppcboot)
• clean up code
• make it easier to add custom boards
• make it possible to add other [PowerPC] CPUs
• extend functions, especially:
• Provide extended interface to Linux boot loader
• S-Record download
• network boot
• PCMCIA / CompactFlash / ATA disk / SCSI ... boot
• create ARMBoot project (http://sourceforge.net/projects/armboot)
• add other CPU families (starting with ARM)
• create U-Boot project (http://sourceforge.net/projects/u-boot)
• current project page: see http://www.denx.de/wiki/U-Boot

Names and Spelling: ===================

The "official" name of this project is "Das U-Boot". The spelling "U-Boot" shall be used in all written text (documentation, comments in source files etc.). Example:

This is the README file for the U-Boot project.

File names etc. shall be based on the string "u-boot". Examples:

include/asm-ppc/u-boot.h

#include

Variable names, preprocessor constants etc. shall be either based on the string "u_boot" or on "U_BOOT". Example:

U_BOOT_VERSION u_boot_logo IH_OS_U_BOOT u_boot_hush_start

Versioning: ===========

Starting with the release in October 2008, the names of the releases were changed from numerical release numbers without deeper meaning into a time stamp based numbering. Regular releases are identified by names consisting of the calendar year and month of the release date. Additional fields (if present) indicate release candidates or bug fix releases in "stable" maintenance trees.

Examples: U-Boot v2009.11 - Release November 2009 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release

Directory Hierarchy: ====================

/arch Architecture specific files /arc Files generic to ARC architecture /arm Files generic to ARM architecture /m68k Files generic to m68k architecture /microblaze Files generic to microblaze architecture /mips Files generic to MIPS architecture /nds32 Files generic to NDS32 architecture /nios2 Files generic to Altera NIOS2 architecture /openrisc Files generic to OpenRISC architecture /powerpc Files generic to PowerPC architecture /riscv Files generic to RISC-V architecture /sandbox Files generic to HW-independent "sandbox" /sh Files generic to SH architecture /x86 Files generic to x86 architecture /api Machine/arch independent API for external apps /board Board dependent files /cmd U-Boot commands functions /common Misc architecture independent functions /configs Board default configuration files /disk Code for disk drive partition handling /doc Documentation (don't expect too much) /drivers Commonly used device drivers /dts Contains Makefile for building internal U-Boot fdt. /examples Example code for standalone applications, etc. /fs Filesystem code (cramfs, ext2, jffs2, etc.) /include Header Files /lib Library routines generic to all architectures /Licenses Various license files /net Networking code /post Power On Self Test /scripts Various build scripts and Makefiles /test Various unit test files /tools Tools to build S-Record or U-Boot images, etc.

Software Configuration: =======================

Configuration is usually done using C preprocessor defines; the rationale behind that is to avoid dead code whenever possible.

There are two classes of configuration variables:

• Configuration _OPTIONS_:

These are selectable by the user and have names beginning with "CONFIG_".

• Configuration _SETTINGS_:

These depend on the hardware etc. and should not be meddled with if you...