[Xorg] The big multiconsole nasty

Egbert Eich eich at pdx.freedesktop.org
Mon Jul 12 04:52:24 PDT 2004

Jon Smirl writes:
 > While trying to fix the radeonfb driver, BenH has run into some laptops
 > that take the system BIOS and VBIOS, put them into a single image,
 > compress it, and put it into a ROM. They can do this because the video
 > is build into the motherboard. I don't know how you are going to find
 > this without help from the system or using the C000:0 copy.

With some tricks (possibly by using the BIOS system vectors) you can
often locate pages where the BIOS lives. Of course you can only use
the pre-POSTED copy which lives somehwere beween 0xc0000 and 0xfffff.

On these systems I have found that it is unwise to re-POST anyway
as this may lead to undesireable results. In the best case the video
BIOS tries to call into some vendor specific call in the system BIOS.


More information about the xorg mailing list