util/amdfwtool: Add options to separate signed firmwares
Add support for separating signed firmwares into another CBFS. If
sig_opt flag in AMD/PSPFW file header is 1, it means that the firmware
is signed against AMD chain of trust and will be verified by PSP. If
those firmware binaries are put outside FW_MAIN_[AB], vboot can skip
redundant verification, improving overall verification time.
BUG=b:
206909680
TEST=Build amdfwtool. Build Skyrim BIOS image and boot to OS.
Change-Id: I9f3610a7002b2a9c70946b083b0b3be6934200b0
Signed-off-by: Kangheui Won <khwon@chromium.org>
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59866
Reviewed-by: Jon Murphy <jpmurphy@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>