|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. However, this can be easily fixed by reading the IFD with flashrom, editing the correct values into it with ifdtool and then reflashing it.
Create a layout.txt with the following contents:
00000000:00000fff fd 00180000:003fffff bios 00001000:0017ffff me
After that, simply run:
sudo flashrom -p internal --ifd -i fd -r ifd.rom ifdtool -n layout.txt ifd.rom sudo flashrom -p internal --ifd -i fd -w ifd.rom.new
After flashing, power cycle the computer to ensure the new IFD is being used. If only a reboot is done, the old IFD layout is still seen by flashrom, even if the IFD on the flash chip is correctly defining the new region layout.