Add support for ram payloadsrampayload

This is enabled by CONFIG_RAMPAYLOAD.

The code will look for a ram payload and, if it is found, try
to run it. If the load fails or the payload returns it will
continue with ramstage.

We also include a new payload, linuxcheck, which is intended
to verify that linux can be loaded and run, e.g. as a LinuxBoot
payload. Currently, it fails.

This does not yet work but it makes sense as a foundation on which
to build. For one thing, we need to build at least a few tables
for Linux. The goal for LinuxBoot is to build as few as possible.

To test with linuxcheck (linux is not even close to working):
cd payloads/linuxcheck/
cp x86config  .config
make

cd ../..
make

./build/cbfstool build/coreboot.rom add-payload -n fallback/rampayload -f payloads/linuxcheck/linuxcheck.elf

qemu-system-x86_64 -nographic -m 8192 -bios build/coreboot.rom -monitor /dev/pts/$1 -s

We need to change the payload menu so we can add a rampayload but it's a bit
tricky as written, so that must come later.

Note that I'm still creating a special purpose romselfboot. The idea of
merging romselfboot and selfboot is probably a good idea -- in the future.
I think until we know how this should look, such a merge is premature.

Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>

Change-Id: I8199aae6776f6dee969b370b0e6a41ef96e854d8
clang-formatted-by: Ronald G. Minnich
Reviewed-on: https://review.coreboot.org/28402
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Tested-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/arch/x86/cbfs_and_run.c b/src/arch/x86/cbfs_and_run.c
index f25052b1edb3..cd36dbbea9b6 100644
--- a/src/arch/x86/cbfs_and_run.c
+++ b/src/arch/x86/cbfs_and_run.c
@@ -18,5 +18,7 @@
 
 asmlinkage void copy_and_run(void)
 {
+	if (IS_ENABLED(CONFIG_RAMPAYLOAD))
+		run_ramprog();
 	run_ramstage();
 }