Subject: Re: XFree86 4.0.* palette unfriendliness
To: John Franklin <firstname.lastname@example.org>
From: Ken Hornstein <email@example.com>
Date: 02/13/2001 14:13:54
>Are you referring to being able to drop back to text mode on panic? That
>would be nice. How many different ways is mode select done? Can this
>be added to the vga driver? I don't think it'd be worth it to do the
>same thing to the vga driver we do with the audio driver (have a front
>end audio device and a back end card driver) unless we go all out and
>use it as a means for XFree86 to access the cards and their features.
It really is card-specific, and seems to vary even from model to model
(depending on the card).
The problem I see now is right now is the VGA driver knows nothing
about the specific card ... it just sees a card that implements the VGA
register set, but the high-resolution stuff is outside of the VGA
register set. You'd have to teach the VGA driver about the n-billion
different graphic cards out there to get it to be able to do them all.
Easy to do for one - damn hard to do for them all. Somehow, placing
all of XFree86 inside the kernel isn't a reasonable option, I think :-/
Now, it seems to me that on panic you _might_ be able to invoke the
INT10 BIOS extension that XFree86 uses to reset secondary video cards
and be able to get back to text mode ... but of course, you could never
continue from DDB when you've done that. But ... "might be useful".