diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_ringbuffer.c')
-rw-r--r-- | drivers/gpu/drm/i915/intel_ringbuffer.c | 19 |
1 files changed, 8 insertions, 11 deletions
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 89a65be8a3f3..31cd7e33e820 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -696,20 +696,17 @@ int intel_wait_ring_buffer(struct drm_device *dev, drm_i915_private_t *dev_priv = dev->dev_private; u32 head; - head = intel_read_status_page(ring, 4); - if (head) { - ring->head = head & HEAD_ADDR; - ring->space = ring->head - (ring->tail + 8); - if (ring->space < 0) - ring->space += ring->size; - if (ring->space >= n) - return 0; - } - trace_i915_ring_wait_begin (dev); end = jiffies + 3 * HZ; do { - ring->head = I915_READ_HEAD(ring) & HEAD_ADDR; + /* If the reported head position has wrapped or hasn't advanced, + * fallback to the slow and accurate path. + */ + head = intel_read_status_page(ring, 4); + if (head < ring->actual_head) + head = I915_READ_HEAD(ring); + ring->actual_head = head; + ring->head = head & HEAD_ADDR; ring->space = ring->head - (ring->tail + 8); if (ring->space < 0) ring->space += ring->size; |