On Wed, Dec 17, 2014 at 04:41:42PM +0000, Chris Wilson wrote: > On gen2-4, we have a separate pageflip prepare/finish phase. The intent > of the stall check is to detect when we have incurred a delay, > potentially indefinite, after the pageflip is submitted and before the > flip is processed by the hardware. However, our notion of > INTEL_FLIP_PENDING/INTEL_FLIP_COMPLETE do not tally with how we set the > values during prepare/finish and the current stall check erroneously > assumes that when the pending value >= COMPLETE, the driver has seen the > hardware completion flag. But what the driver actually means, is that it > has seen the acknowlegement that the flip is queued and is now pending > the completion event. Bah, otoh, as we don't mark the flip as pending before completion on gen5+, we know don't detect when the flip is wedged there after applying this patch. It is quite possible that the work->pending check is entirely bogus. Back to the drawing board. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
