|In circuit flashing||Yes|
|Dual BIOS feature||Yes|
The main SPI flash can be accessed using flashrom. The DualBIOS backup flash
chip is accessible as well using the
dualbiosindex programmer parameter.
Since the flash recovery mechanism works even with coreboot installed on the
main flash chip (it still restores the vendor UEFI though), it is useful to
leave the backup chip untouched.
Notes about the original firmware¶
The original IFD defines the BIOS region as the whole flash chip. While this is
not an issue if flashing a complete image, it confuses flashrom and trashes the
flash chip’s contents when using the
--ifd option. A possible workaround is
to create a
layout.txt file with a non-overlapping BIOS region:
00000000:00000fff fd 00180000:003fffff bios 00001000:0017ffff me
After that, use flashrom with the new layout file. For example, to create a
backup of the BIOS region and then flash a
sudo flashrom -p internal -l layout.txt -i bios -r backup.rom sudo flashrom -p internal -l layout.txt -i bios -w coreboot.rom
Modifying the IFD so that the BIOS region does not overlap would work as well. However, this makes DualBIOS unable to recover from a bad flash for some reason.