Bug#406373: xserver-xorg-video-ati: [ia64] No direct rendering w/ Radeon R300 [FireGL X1]

["Alex Deucher" <alexdeucher@gmail.com>]

On 1/12/07, Bryan Stillwell <bryan.stillwell@hp.com> wrote:
> Alex Deucher wrote:
> > On 1/11/07, Bryan Stillwell <bryan.stillwell@hp.com> wrote:
> >> However, when running in mergedfb mode, the right ~1/3rd of the second
> >> monitor doesn't work properly.  The first monitor and the first ~2/3rds
> >> of the second monitor work great.  Have you seen anything like that
> >> before, or should I file a separate bug on that?  The best way I could
> >> describe it is garbage, but it seems like some of the graphics are
> >> trying to be displayed.
> >
> > How wide is your mergedfb desktop?  There are some width and height
> > limitations in the 3D engine.
>
> It is 3200x1200.  I would say the 3D engine appears to have problems
> when X is between ~2667 and 3199.  What are the limits?  Are they in the
> card or in the driver?

The limits are in the hardware.  They could potentially be worked
around in the driver, but it's non-trivial.  IIRC, the register
bitfields would indicate 4096x4096, but I think in practice it's
2560x2560 on r300s and more (not sure of the exact limit off hand,
IIRC ~4000 or so) on r400s.

Alex

> Thanks,
> Bryan