documentation on intel driver behavior?
Jesse Barnes
jbarnes at virtuousgeek.org
Fri Feb 29 10:18:59 PST 2008
On Friday, February 29, 2008 12:59 am Michel Dänzer wrote:
> On Wed, 2008-02-27 at 16:55 -0800, Eric Anholt wrote:
> > For vblank syncing, we wait for vblank before emitting that copy.
> > Note that we're not doing anything about guaranteeing that that
> > copy happens in any set amount of time. We just assume that the
> > hardware will get to it fast enough (and that we were woken up to
> > do this soon enough) that no tearing occurs.
>
> Nice writeup Eric, I'd just like to add that with drm Git, the 3D
> driver can also schedule buffer swaps to be executed by the DRM at an
> arbitrary vertical blank period. This mechanism uses a tasklet to
> mostly eliminate tearing even with several contexts running
> concurrently.
Yeah, the tasklet stuff is really nice. I wonder if it's something that
could be made into mostly generic code (ala vblank rework) so that
other drivers could use it? I guess that would mean a generic drm
ioctl for it along with a chunk of generic code for handling the
tasklets; I'm not sure how much code it would save on the driver side,
but if it's significant the effort of porting it to the core may be
worth it.
Jesse
More information about the xorg
mailing list