On Thu, Apr 24, 2014 at 09:40:38PM +0200, Pavel Machek wrote: > Hi! > > > And if you can indeed reliably reproduce this a bisect could be really useful. > > And we have a winner here :-) > > Ok, it was not as painfull as I feared. > > It does not revert cleanly, but doing it by hand was not that bad. Oh my. That is bizarre, can you check whether you have commit 9991ae787a0c87fe7c783b4b6f4754c3cdbb6213 Author: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Date: Wed Apr 2 16:36:07 2014 +0100 drm/i915: Move all ring resets before setting the HWS page in your latest kernel? That just makes > commit a51435a3137ad8ae75c288c39bd2d8b2696bae8f > Author: Naresh Kumar Kachhi <naresh.kumar.kachhi@xxxxxxxxx> > Date: Wed Mar 12 16:39:40 2014 +0530 > > drm/i915: disable rings before HW status page setup more consistent wrt g4x. To confirm, on drm-intel-nightly you used a patch like: diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 36a62af..ce6186a 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -494,6 +494,11 @@ static int init_ring_common(struct intel_ring_buffer *ring) I915_READ_TAIL(ring), I915_READ_START(ring)); + if (I915_NEED_GFX_HWS(dev)) + intel_ring_setup_status_page(ring); + else + ring_setup_phys_status_page(ring); + if (!stop_ring(ring)) { /* G45 ring initialization often fails to reset head to zero */ DRM_DEBUG_KMS("%s head not reset to zero " @@ -517,11 +522,6 @@ static int init_ring_common(struct intel_ring_buffer *ring) } } - if (I915_NEED_GFX_HWS(dev)) - intel_ring_setup_status_page(ring); - else - ring_setup_phys_status_page(ring); - reset: /* Initialize the ring. This must happen _after_ we've cleared the ring * registers with the above sequence (the readback of the HEAD registers -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel