Curious experiences with a Radeon on the fritz

[Tormod Volden]

On Wed, Sep 21, 2011 at 8:52 PM, Michael Witten wrote:
> Because my hardware does appear to be malfunctioning due to a corrupt
> video BIOS, it seems prudent to salvage as much as possible from
> its output, so that it is possible to figure out which other values
> need to be hardcoded in case of further corruption.
>
> To do this, I did 2 things:
>
>  * Export the video BIOS data via debugfs, so that it can be
>    easily backed up in secondary storage.
>
>  * Hack the existing Radeon driver code to log information
>    about which values are being read from the video BIOS
>    data and from which offsets these values are being read.
>
> I first wrote the following patch to export the video BIOS via debugfs
> (I wrote a little more than necessary; it should be generally applicable):

Is there any reason to use your debugfs patch instead of reading the
BIOS the "classic" way?

(as root)
(use lspci to get the bus id)
cd /sys/bus/pci/devices/<pci bus id>
echo 1 > rom
cat rom > /tmp/vbios.rom
echo 0 > rom

Regards,
Tormod