Added new config BOOT_DEVICE_SPI_FLASH_NO_EARLY_WRITES to accomodate
older x86 platforms that don't allow writing to SPI flash when early
stages are running XIP from flash. If
BOOT_DEVICE_SPI_FLASH_NO_EARLY_WRITES is not selected,
BOOT_DEVICE_SPI_FLASH_RW_NOMMAP_EARLY will get auto-selected if
BOOT_DEVICE_SPI_FLASH_RW_NOMMAP=y. This allows for current platforms
that write to flash in the earlier stages, assuming that they have
that capability.
BUG=b:150502246
BRANCH=None
TEST=diff the coreboot.rom files resulting from running
./util/abuild/abuild -p none -t GOOGLE_NAMI -x -a --timeless
with and without this change to make sure that there was no
difference. Also did this for GOOGLE_CANDY board, which is
baytrail based (and has BOOT_DEVICE_SPI_FLASH_NO_EARLY_WRITES
enabled).
Change-Id: I3aef8be702f55873233610b8e20d0662aa951ca7
Signed-off-by: Shelley Chen <shchen@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45740
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>