From 7207b366d580b256dc0951bdb0c5eb453929e5d2 Mon Sep 17 00:00:00 2001 From: "Robert P. J. Day" Date: Sat, 19 Dec 2015 07:16:10 -0500 Subject: doc: Tidy up first part of top-level README file First (small) pass at tidying up the README file, including: * remove references to obsolete CREDITS file * remove (some) references to obsolete boards.cfg file * remove at least one reference to a "scrapped" board * cut down unnecessarily detailed directory hierarchy * bunch of grammar and spelling tweaks Signed-off-by: Robert P. J. Day --- README | 128 ++++++++++++++++++++++------------------------------------------- 1 file changed, 43 insertions(+), 85 deletions(-) (limited to 'README') diff --git a/README b/README index 43f307f30f..5ac2d44567 100644 --- a/README +++ b/README @@ -34,12 +34,14 @@ 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 and CREDITS files to find out -who contributed the specific port. The boards.cfg file lists board -maintainers. +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: There is no CHANGELOG file in the actual U-Boot source tree; -it can be created dynamically from the Git log using: +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 @@ -48,7 +50,7 @@ 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 +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 @@ -58,7 +60,7 @@ 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 +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 @@ -133,79 +135,24 @@ Directory Hierarchy: /arch Architecture specific files /arc Files generic to ARC architecture - /cpu CPU specific files - /arc700 Files specific to ARC 700 CPUs - /lib Architecture specific library files /arm Files generic to ARM architecture - /cpu CPU specific files - /arm720t Files specific to ARM 720 CPUs - /arm920t Files specific to ARM 920 CPUs - /at91 Files specific to Atmel AT91RM9200 CPU - /imx Files specific to Freescale MC9328 i.MX CPUs - /s3c24x0 Files specific to Samsung S3C24X0 CPUs - /arm926ejs Files specific to ARM 926 CPUs - /arm1136 Files specific to ARM 1136 CPUs - /pxa Files specific to Intel XScale PXA CPUs - /sa1100 Files specific to Intel StrongARM SA1100 CPUs - /lib Architecture specific library files /avr32 Files generic to AVR32 architecture - /cpu CPU specific files - /lib Architecture specific library files /blackfin Files generic to Analog Devices Blackfin architecture - /cpu CPU specific files - /lib Architecture specific library files /m68k Files generic to m68k architecture - /cpu CPU specific files - /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs - /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs - /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs - /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs - /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs - /lib Architecture specific library files /microblaze Files generic to microblaze architecture - /cpu CPU specific files - /lib Architecture specific library files /mips Files generic to MIPS architecture - /cpu CPU specific files - /mips32 Files specific to MIPS32 CPUs - /mips64 Files specific to MIPS64 CPUs - /lib Architecture specific library files /nds32 Files generic to NDS32 architecture - /cpu CPU specific files - /n1213 Files specific to Andes Technology N1213 CPUs - /lib Architecture specific library files /nios2 Files generic to Altera NIOS2 architecture - /cpu CPU specific files - /lib Architecture specific library files /openrisc Files generic to OpenRISC architecture - /cpu CPU specific files - /lib Architecture specific library files /powerpc Files generic to PowerPC architecture - /cpu CPU specific files - /mpc5xx Files specific to Freescale MPC5xx CPUs - /mpc5xxx Files specific to Freescale MPC5xxx CPUs - /mpc8xx Files specific to Freescale MPC8xx CPUs - /mpc8260 Files specific to Freescale MPC8260 CPUs - /mpc85xx Files specific to Freescale MPC85xx CPUs - /ppc4xx Files specific to AMCC PowerPC 4xx CPUs - /lib Architecture specific library files + /sandbox Files generic to HW-independent "sandbox" /sh Files generic to SH architecture - /cpu CPU specific files - /sh2 Files specific to sh2 CPUs - /sh3 Files specific to sh3 CPUs - /sh4 Files specific to sh4 CPUs - /lib Architecture specific library files /sparc Files generic to SPARC architecture - /cpu CPU specific files - /leon2 Files specific to Gaisler LEON2 SPARC CPU - /leon3 Files specific to Gaisler LEON3 SPARC CPU - /lib Architecture specific library files /x86 Files generic to x86 architecture - /cpu CPU specific files - /lib Architecture specific library files /api Machine/arch independent API for external apps /board Board dependent files /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 @@ -213,13 +160,12 @@ Directory Hierarchy: /examples Example code for standalone applications, etc. /fs Filesystem code (cramfs, ext2, jffs2, etc.) /include Header Files -/lib Files generic to all architectures - /libfdt Library files to support flattened device trees - /lzma Library files to support LZMA decompression - /lzo Library files to support LZO decompression +/lib Library routines generic to all architectures +/Licenses Various license files /net Networking code /post Power On Self Test -/spl Secondary Program Loader framework +/scripts Various build scripts and Makefiles +/test Various unit test files /tools Tools to build S-Record or U-Boot images, etc. Software Configuration: @@ -239,11 +185,11 @@ There are two classes of configuration variables: you don't know what you're doing; they have names beginning with "CONFIG_SYS_". -Later we will add a configuration tool - probably similar to or even -identical to what's used for the Linux kernel. Right now, we have to -do the configuration by hand, which means creating some symbolic -links and editing some configuration files. We use the TQM8xxL boards -as an example here. +Previously, all configuration was done by hand, which involved creating +symbolic links and editing configuration files manually. More recently, +U-Boot has added the Kbuild infrastructure used by the Linux kernel, +allowing you to use the "make menuconfig" command to configure your +build. Selection of Processor Architecture and Board Type: @@ -257,10 +203,9 @@ Example: For a TQM823L module type: cd u-boot make TQM823L_defconfig -For the Cogent platform, you need to specify the CPU type as well; -e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent -directory according to the instructions in cogent/README. - +Note: If you're looking for the default configuration file for a board +you're sure used to be there but is now missing, check the file +doc/README.scrapyard for a list of no longer supported boards. Sandbox Environment: -------------------- @@ -277,13 +222,25 @@ Board Initialisation Flow: -------------------------- This is the intended start-up flow for boards. This should apply for both -SPL and U-Boot proper (i.e. they both follow the same rules). At present SPL -mostly uses a separate code path, but the funtion names and roles of each -function are the same. Some boards or architectures may not conform to this. -At least most ARM boards which use CONFIG_SPL_FRAMEWORK conform to this. +SPL and U-Boot proper (i.e. they both follow the same rules). + +Note: "SPL" stands for "Secondary Program Loader," which is explained in +more detail later in this file. + +At present, SPL mostly uses a separate code path, but the function names +and roles of each function are the same. Some boards or architectures +may not conform to this. At least most ARM boards which use +CONFIG_SPL_FRAMEWORK conform to this. + +Execution typically starts with an architecture-specific (and possibly +CPU-specific) start.S file, such as: + + - arch/arm/cpu/armv7/start.S + - arch/powerpc/cpu/mpc83xx/start.S + - arch/mips/cpu/start.S -Execution starts with start.S with three functions called during init after -that. The purpose and limitations of each is described below. +and so on. From there, three functions are called; the purpose and +limitations of each of these functions are described below. lowlevel_init(): - purpose: essential init to permit execution to reach board_init_f() @@ -6630,7 +6587,8 @@ it: * A CHANGELOG entry as plaintext (separate from the patch) -* For major contributions, your entry to the CREDITS file +* 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. -- cgit v1.2.3