[LinuxBIOS] any chance to get X fbdev driver to work ?

Richard Smith smithbone at gmail.com
Wed Dec 28 18:48:40 CET 2005

On 12/28/05, Ronald G Minnich <rminnich at lanl.gov> wrote:
> Christian Sühs wrote:
> > It seems that the content on 0x0c0000 is not the same as the vgabios
> > Only the first (between Offset 0x00 and Offset 0x7f) words are the same.
> > The rest differs from vgabios (Offset 0x80 - 0xFFFF). That is the reason
> > why X detects a valid vga-Bios section on Offset 00 and 01 (55aa) and
> > the rest fails.
> >
> > Now, I will have a look why this happens.
> > Any hint?
> >
> as ollie has mentioned, VGA bios are frequently self-modifying code.
> Once the system is up, you are looking at the code AFTER
> self-modification has happened.

I guess I misread.  I though he indicated that large areas of the code
that was supposed to be 0xff was not.

It works with the factory bios but does not with linuxbios. Yes?  So
if thats the case then the self-modification is probally not the
problem.  Also it shouldn't change checksums from run to run.

Is it possible to diff the contents of 0xc0000-0x0d0000 under both the
factory and linux bios?  I think you may have said that you have to
use different copy of the video bios for linuxbios?

Grrrr... We really need to get this stuff going under the emulator to
make it easier to figure out whats up.

Richard A. Smith

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