Re: Overriding X on panic

["D. Hazelton" <dhazelton@enter.net>]

On Sunday 26 November 2006 17:19, Dave Airlie wrote:
> On 11/27/06, Alan <alan@lxorguk.ukuu.org.uk> wrote:
> > On Sun, 26 Nov 2006 09:18:41 +0100
> >
> > Arjan van de Ven <arjan@infradead.org> wrote:
> > > > The mode switch sequences for modern cards are a bit more hairy than
> > > > lists of I/O poking unfortunately.
> > >
> > > for the Intel hw Keith doesn't seem to think it's all that much of a
> > > problem though...
> >
> > Including the TV out, odder LCD panels, non BIOS modes etc ? If so then
> > it might be an interesting test case for intelfb to grow some kind of
> > console helper interface
>
> It's non-trivial, I think you are better off going initially with just
> using the current framebuffer that X is using, I know ajax was doing
> some hacking on this with a "user"-framebuffer, until I disuaded him
> due to I think the trouble caused by dual-head and something else I
> can't remember..
>
> I personally think we need to probably just bite the bullet and start
> sticking graphics drivers into the kernel, the new randr-1.2 interface
> for X is probably a good starting point for a generic mode setting
> interface that isn't so X dependent and could replace fbdev with
> something more sane wrt dualhead and multiple outputs... fbdev could
> be implemented on top of that layer then.. also suspend/resume really
> needs this sort of thing....

I've been working on this myself. Unfortunately the box I was using for devel 
has died and the start I made on the work was lost several months ago when I 
had a hard drive die on me. (I really need to go buy a UPS and a better surge 
protector - the box I was doing devel on bought it in a lightning strike and 
the hard drive I had used as a backup just died)

> My main worry with integrating graphics drivers into the kernel is
> that when they don't work the user gets no screen, with network/sound
> etc this isn't so bad, but if they can't see a screen debugging gets
> to be a bit more difficult....

Yeah - this is why the work I was doing kept the old vgacon around and used 
fbcon on those platforms that needed it (unchanged). My plan was to add a 
graphics system that would "take over" from the boot console when it was 
ready to take over.

DRH