On Fri, Oct 31, 2014 at 11:12:33AM +0200, Jani Nikula wrote: > We have drm_crtc_vblank_off very early in the disable sequence, and > drm_crtc_vblank_on very late in the enable sequence. Especially > early/late since > > commit 4b3a9526fc3228e74011b88f58088336acd2c9e2 > Author: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > Date: Thu Aug 14 22:04:37 2014 +0300 > > drm/i915: Move vblank enable earlier and disable later > > All of the audio codec enable/disable stuff, like most of mode set, is > done with vblank disabled. > > Since > > commit 44bd93a3d367913d883be6abba9a6e51a53c4e90 > Author: Daniel Vetter <daniel.vetter@xxxxxxxx> > Date: Fri Jul 25 23:36:44 2014 +0200 > > drm/i915: Use generic vblank wait > > we started using drm_wait_one_vblank instead of directly checking the > registers in intel_wait_for_vblank, and this specifically disallows its > use during mode set (and IIRC we've seen bug reports about that too). > > I don't know what the correct answer should be here. I've ensured the > audio codec enable doesn't happen until after the port/pipe are up and > running, but I still can't vblank wait. Yeah, this is a big ugly. We really can't enable vblanks earlier since on some ports the pipe really only starts running later on. Imo the proper fix is to push the audio/infoframe setup into a vblank work item, and the code here would only schedule that on the very next vblank. Unfortunately that infrastructure isn't there yet, so meanwhile I think we need to locally resurrect the old vblank_wait functions with a big XXX comment. Or given that we've never really cared about actually running in the vblank (the wait_for macro uses msleeps, so we're pretty much guaranteed to miss the actual vblank) just insert FIXME comments stating what should be done here. I'm ok with either approach really. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
