Boards may want to specify a board-specific U-Boot revision. At the very
least, pseudo-boards for u-boot-libre releases will need to specify their
U-Boot versions somehow.
Copy the existing mechanism from download/coreboot for specifying
build info with board.cfg files. Specify the commit hash for the
'v2021.07' pseudo-board, and 'master' as the default.
Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Once the tarball are released, it will enable distributions to use
these tarballs to produce deblobbed u-boot packages.
Note that the produced tarball is not reproducible yet. Because of
that it has to be trusted.
During a release, it's a good idea to sign the uncompressed tarball as
the various compression formats and associated tools make different
tradeoffs.
For instance with xz, xz -9e tends to compress really well with the
the most used xz[1] implementation, and most GNU/Linux users probably
already have it installed, but and the drawbacks is that the format is
very fragile[2].
The lzip format is more suited for long term archiving but its most
packaged implementation[3] is less likely to be already installed by
users than more well known formats like xz, bzip2 or gzip.
Being able to add more compression formats after the release is also
useful, for instance to accommodate different build systems or use
cases (like being able to build u-boot with less dependencies in
distributions like Guix, or building u-boot directly on devices which
don't have enough RAM for xz for instance).
[1]https://tukaani.org/xz/
[2]https://www.nongnu.org/lzip/xz_inadequate.html
[3]https://www.nongnu.org/lzip/
Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>
Leah Rowe