[LinuxBIOS] mcp55 flashrom problem

Ward Vandewege ward at gnu.org
Thu Mar 1 06:05:31 CET 2007

Hi all,

Richard and I spent most of this evening chasing a suspected hardware problem
that turned out to be not a hardware problem, but a flashrom problem.

Basically, I had made a copy of the rom with flashrom earlier today, and
Richard soldered a PLCC socket onto our board this evening. After that, the
board booted fine, but when reading out the rom image with flashrom again, it
came up as slightly different - 115 bytes of difference out of 512K.

Eventually, we realized that the image we read out *changed after every
boot*. We also diffed the image that is downloadable from Gigabyte of this
particular BIOS revision, and it's nothing like what flashrom returns. While
they are the same size, the flashrom copy looks like it is uncompressed (and
only part of the real BIOS), while the downloadable image has hardly any
recognizable strings in it - it's probably compressed somehow.

It looks like flashrom is not disabling shadow properly. This is probably
related to my patch of earlier today that added a new pci id for this
particular board's MCP55 (0x0360). Flashrom only knew about 0x0364 and 0x0367
for the MCP55.

I also saw a patch from Ed Swierk a couple of weeks ago, which added a whole
bunch of PCI ids for the MCP55 (among which the 0x0360), but was never
applied to the tree.

Can someone who knows the MCP55 have a look at the enable_flash_mcp55
function in flash_enable.c and figure out what's wrong?

Yinghai, can you tell us which board(s) you've tested the enable_flash_mcp55
function on?

Richard and Ward.

Ward Vandewege <ward at fsf.org>
Free Software Foundation - Senior System Administrator

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