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, 34 insertions, 0 deletions

diff --git a/payloads/linuxcheck/Makefile b/payloads/linuxcheck/Makefile
new file mode 100644
index 000000000000..0e3feae90d02
--- /dev/null
+++ b/payloads/linuxcheck/Makefile
@@ -0,0 +1,34 @@
+LIBPAYLOAD_DIR=$(CURDIR)/libpayload
+XCOMPILE=$(LIBPAYLOAD_DIR)/libpayload.xcompile
+# build libpayload and put .config file in $(CURDIR) instead of ../libpayload
+# to avoid pollute the libpayload source directory and possible conflicts
+LPOPTS=obj="$(CURDIR)/build" DESTDIR="$(CURDIR)" DOTCONFIG="$(CURDIR)/.config"
+CFLAGS += -Wall -Werror -Os -ffreestanding -nostdinc -nostdlib
+
+all: linuxcheck.elf
+
+$(LIBPAYLOAD_DIR):
+	$(MAKE) -C ../libpayload $(LPOPTS) defconfig
+	$(MAKE) -C ../libpayload $(LPOPTS)
+	$(MAKE) -C ../libpayload $(LPOPTS) install
+
+ifneq ($(strip $(wildcard libpayload)),)
+include $(XCOMPILE)
+LPGCC = CC="$(GCC_CC_x86_32)" "$(LIBPAYLOAD_DIR)/bin/lpgcc"
+%.elf: %.c Makefile
+	$(LPGCC) $(CFLAGS) -o $*.elf $*.c
+else
+# If libpayload is not found, first build libpayload,
+# then do the make, this time it'll find libpayload
+# and generate the linuxcheck.elf target
+%.elf: $(LIBPAYLOAD_DIR)
+	$(MAKE) all
+endif
+
+clean:
+	rm -f linuxcheck.elf
+
+distclean: clean
+	rm -rf build libpayload .config .config.old
+
+.PHONY: all clean distclean