From 9b95f3f7ffb77fd53b2fad7197de2b379f7fac3e Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Thu, 4 Feb 2021 21:17:12 -0700 Subject: [PATCH] README: Add doumentation for version information There are quite a few available version options in U-Boot. Add a list of the available Makefile variables and #defines, along with examples. Signed-off-by: Simon Glass Reviewed-by: Bin Meng --- doc/develop/index.rst | 1 + doc/develop/version.rst | 93 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 94 insertions(+) create mode 100644 doc/develop/version.rst diff --git a/doc/develop/index.rst b/doc/develop/index.rst index beaa64d..ac57fdb 100644 --- a/doc/develop/index.rst +++ b/doc/develop/index.rst @@ -13,6 +13,7 @@ Implementation global_data logging menus + version Debugging --------- diff --git a/doc/develop/version.rst b/doc/develop/version.rst new file mode 100644 index 0000000..6da31a4 --- /dev/null +++ b/doc/develop/version.rst @@ -0,0 +1,93 @@ +.. SPDX-License-Identifier: GPL-2.0+ +.. Copyright (c) 2013 The Chromium OS Authors. + +Version information +=================== + +U-Boot releases are named by year and patch level, for example 2020.10 means the +release that came out in October 2020. Release candidates are tagged every few +weeks as the project heads to the next release. So 2020.10-rc1 was the first +release candidate (RC), tagged soon after 2020.07 was released. + +See https://www.denx.de/wiki/view/U-Boot/ReleaseCycle for full details. + +Within the build system, various Makefile variables are created, making use of +VERSION, PATCHLEVEL and EXTRAVERSION defined at the top of 'Makefile'. There is +also SUBLEVEL available for downstream use. See also CONFIG_IDENT_STRING. + +Some variables end up in a generated header file at +include/generated/version_autogenerated.h and can be accessed from C source by +including + +The following are available: + + UBOOTRELEASE (Makefile) + Full release version as a string. If this is not a tagged release, it also + includes the number of commits since the last tag as well as the the git + hash. If there are uncommitted changes a '-dirty' suffix is added too. + + This is written by scripts/setlocalversion (maintained by Linux) to + include/config/uboot.release and ends up in the UBOOTRELEASE Makefile + variable. + + Examples:: + + 2020.10-rc3 + 2021.01-rc5-00248-g60dd854f3ba-dirty + + PLAIN_VERSION (string #define) + This is UBOOTRELEASE but available in C source. + + Examples:: + + 2020.10 + 2021.01-rc5-00248-g60dd854f3ba-dirty + + UBOOTVERSION (Makefile) + This holds just the first three components of UBOOTRELEASE (i.e. not the + git hash, etc.) + + Examples:: + + 2020.10 + 2021.01-rc5 + + U_BOOT_VERSION (string #define) + "U-Boot " followed by UBOOTRELEASE, for example:: + + U-Boot 2020.10 + U-Boot 2021.01-rc5 + + This is used as part of the banner string when U-Boot starts. + + U_BOOT_VERSION_STRING (string #define) + U_BOOT_VERSION followed by build-time information + and CONFIG_IDENT_STRING. + + Examples:: + + U-Boot 2020.10 (Jan 06 2021 - 08:50:36 -0700) + U-Boot 2021.01-rc5-00248-g60dd854f3ba-dirty (Jan 06 2021 - 08:50:36 -0700) for spring + +Build date/time is also included. See the generated file +include/generated/timestamp_autogenerated.h for the available +fields. For example:: + + #define U_BOOT_DATE "Jan 06 2021" (US format only) + #define U_BOOT_TIME "08:50:36" (24-hour clock) + #define U_BOOT_TZ "-0700" (Time zone in hours) + #define U_BOOT_DMI_DATE "01/06/2021" (US format only) + #define U_BOOT_BUILD_DATE 0x20210106 (hex yyyymmdd format) + #define U_BOOT_EPOCH 1609948236 + +The Epoch is the number of seconds since midnight on 1/1/70. You can convert +this to a time with:: + + $ date -u -d @1609948236 + Wed 06 Jan 2021 03:50:36 PM UTC + $ date -d 'Wed 06 Jan 2021 03:50:36 PM UTC' +%s + 1609948236 + +Every time you build U-Boot this will update based on the time +on your build machine. See 'Reproducible builds' if you want to +avoid that. -- 2.7.4