diff options
| -rw-r--r-- | drivers/gpu/drm/i915/intel_ringbuffer.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 2d6039b4571f..3bd85f7e3904 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -150,8 +150,6 @@ static int init_ring_common(struct intel_ring_buffer *ring) I915_WRITE_HEAD(ring, 0); ring->write_tail(ring, 0); - /* Initialize the ring. */ - I915_WRITE_START(ring, obj->gtt_offset); head = I915_READ_HEAD(ring) & HEAD_ADDR; /* G45 ring initialization fails to reset head to zero */ @@ -177,6 +175,11 @@ static int init_ring_common(struct intel_ring_buffer *ring) } } + /* Initialize the ring. This must happen _after_ we've cleared the ring + * registers with the above sequence (the readback of the HEAD registers + * also enforces ordering), otherwise the hw might lose the new ring + * register values. */ + I915_WRITE_START(ring, obj->gtt_offset); I915_WRITE_CTL(ring, ((ring->size - PAGE_SIZE) & RING_NR_PAGES) | RING_REPORT_64K | RING_VALID); |