libre mrc on haswell is quite buggy for now, but works in
a limited fashion
this patch re-adds the old configs, but as _mrc for example
t440p_12mb_mrc instead of t440p_12mb
and t440p_12mb (without _mrc) still uses the libre mrc code
courtesy of Angel Pons from the coreboot project
this uses the following patch set from gerrit, as yet
unmerged (in coreboot master) on this date:
https://review.coreboot.org/c/coreboot/+/64198/5
logic for downloading mrc blobs has been deleted from
lbmk, as this is now completely obsolete (for haswell
boards)
if other platforms are added later that need mrc.bin,
then logic will be re-added again for that
some checks check for specific utils, which are
then used to indicate the existence of other utils,
which means that building them singularly, as is
currently done, may result in errors later if another
tool doesn't exist compiled yet
this is an obscure bug, fixed by this patch. more of a
workaround really. a dirty hack. when checking for any
of the coreboot utilities required, build all coreboot
utilities that are possibly required
the utilities are small enough that this does not add
much extra time to build, and in most cases, all of them
will be needed anyway
the --nuke option in ifdtool will be used instead, to nuke
the ME regions in specific rom sets (and cbfstool will be
used to delete mrc.bin files from rom sets)
the new method being implemented is heavier on disk io, but
simplifies lbmk, and disk io could still be optimised in
the following ways:
* when copying roms from boards with ME in them, use
ifdtool --nuke to get filename.rom.new, and *move* (not copy)
filename.rom.new to the new destination (for use with tar)
* possibly modify ifdtool to make efficient use of mmap for
disk i/o; it currently loads entire roms into an allocated
buffer in memory
the intended use-case scenario was one in which vga rom initialisation
would be used, on desktop configurations, but without coreboot itself
handling vga rom initialisation, instead leaving that task to seabios
it was assumed that grub, when running on the bare metal with
build option "--with-platform=coreboot" would be able to display
like this, but it is not so when tested
in such setups (add-on gpu with grub payload), it is necessary to
extract the video bios and insert it into the coreboot rom, having
coreboot handle such execution. this is beyond the scope of lbmk,
in context of automated building, because we cannot reliably predict
things such as PCI IDs
do away with this build option entirely, for it does not serve the
intended purpose. it will be necessary to run PC GRUB instead (build
option --with-platform=i386-pc). PC GRUB can still read from CBFS,
and you could provide it as a floppy image file inside CBFS for
SeaBIOS to execute. in this setup, GRUB would function as originally
intended by the seabios_withgrub option; such a configuration is
referred to as "SeaGRUB" by the libreboot project, and experimentation
was done with it in the past, to no avail
it's better to keep things simple, in the libreboot project. simpler
for users, that is
Leah Rowe