radeon, apertures & memory mapping

[Benjamin Herrenschmidt]

On Mon, 2005-03-14 at 11:20 -0500, Michel Dänzer wrote:
> On Mon, 2005-03-14 at 18:12 +1100, Benjamin Herrenschmidt wrote:
> > On Sun, 2005-03-13 at 23:28 -0500, Michel Dänzer wrote:
> > > On Sun, 2005-03-13 at 17:43 +1100, Benjamin Herrenschmidt wrote:
> > > > 
> > > > And finally, I want to blank the screen (using the accel engine) before
> > > > setting the new mode, so that we come out "clean" of the mode setting
> > > > (without ugly artifact), and I will probably clean both fb's (simpler).
> > > 
> > > That would break X with UseFBDev.
> > 
> > How so ?
> 
> X assumes that the framebuffer (as in video RAM) contents are preserved
> on mode switches.

Which I consider bogus :) Oh well... does it do a lot of other crappy
assumptions like that ? What if I just can't allocate it and decide to
put it elsewhere in vram ? (unlikely with my current scheme but
possible). X needs to be fixed.

Ben.