On Wed, 2011-04-27 at 11:08 +0200, Michel D?nzer wrote: > On Mit, 2011-04-27 at 18:58 +1000, Christopher James Halse Rogers > wrote: > > On Wed, 2011-04-27 at 10:32 +0200, Michel D?nzer wrote: > > > On Mit, 2011-04-27 at 16:10 +1000, christopher.halse.rogers at > > > canonical.com wrote: > > > > From: Christopher James Halse Rogers <christopher.halse.rogers at > > > > canonical.com> > > > > > > > > This is the least-bad behaviour. It means that we signal the > > > > vblank event before it actually happens, but since we're disabling > > > > vblanks there's no guarantee that it will *ever* happen otherwise. > > > > > > This may indeed be the best we can do for events that are pending when > > > the CRTC is disabled[0], but I can't see anything that would prevent new > > > events from getting scheduled (or synchronous vblank waits from timing > > > out) while the CRTC is disabled? > > > > > > [0] Though it might unnecessarily send events prematurely when the CRTC > > > is just disabled temporarily, e.g. as part of a modeset. > > > > > > > > > Also, this patch won't seem to help at all for other drivers which don't > > > call drm_vblank_off() directly when disabling a CRTC. > > > > This is true. On the other hand, the other drivers don't wedge the > > vblank code into a state where vblanks cannot be re-enabled. So it's > > only a problem when disabling one of 2+ monitors on those drivers, > > And with DPMS? >
Possibly. Since vblanks aren't wedged off in this case it's more likely that the user turning the monitors back on will result in a vblank irq, which will kick everything back into correct operation. I've not managed to trigger this on my radeon system in the same way as my intel systems, but I haven't stressed it as hard either. -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 490 bytes Desc: This is a digitally signed message part URL: <http://lists.freedesktop.org/archives/dri-devel/attachments/20110427/edd0bccc/attachment.pgp>
