Hi,
I want to flash a legacy BIOS on my ASUS A8N-SLI Deluxe, but to make sure I don't screw up, I tried to backup the existing BIOS first. However, running a binary diff between the image extracted from the chip via flash_rom and the vendor-supplied image of the same BIOS version, it seems that a few sections differ. The image is 512 kb big.
From 0x0040000-0x005fff0, flash_rom reads only contents
with all bits set, while the vendor-supplied image contains meaningful data there.
From 0x006e000-0x006e8c0, the contents also differ, but
it seems that one is only meaningful for the extracted image.
My first thought was to just exclude 0x006e000-0x006e8c0 from flashing, but the fact that flash_rom read only 0xff from 0x0040000-0x005fff0 made me worried.
Do you have any suggestions how to find out whether the results above are expected?
switch:/storage/LinuxBIOSv2-2251/util/flashrom # ./flashrom Calibrating delay loop... ok No LinuxBIOS table found. Enabling flash write on NVIDIA CK804...OK SST49LF004A/B found at physical address: 0xfff80000 Flash part is SST49LF004A/B OK, only ENABLING flash write, but NOT FLASHING.
Thanks, Carl-Daniel