diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_ringbuffer.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_ringbuffer.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 371f4c1fc33c..69852ac4018d 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -2552,14 +2552,25 @@ void intel_ring_init_seqno(struct intel_engine_cs *engine, u32 seqno) { struct drm_i915_private *dev_priv = to_i915(engine->dev); + /* Our semaphore implementation is strictly monotonic (i.e. we proceed + * so long as the semaphore value in the register/page is greater + * than the sync value), so whenever we reset the seqno, + * so long as we reset the tracking semaphore value to 0, it will + * always be before the next request's seqno. If we don't reset + * the semaphore value, then when the seqno moves backwards all + * future waits will complete instantly (causing rendering corruption). + */ if (INTEL_INFO(dev_priv)->gen == 6 || INTEL_INFO(dev_priv)->gen == 7) { I915_WRITE(RING_SYNC_0(engine->mmio_base), 0); I915_WRITE(RING_SYNC_1(engine->mmio_base), 0); if (HAS_VEBOX(dev_priv)) I915_WRITE(RING_SYNC_2(engine->mmio_base), 0); } + memset(engine->semaphore.sync_seqno, 0, + sizeof(engine->semaphore.sync_seqno)); engine->set_seqno(engine, seqno); + engine->hangcheck.seqno = seqno; } |