From: Ville Syrjälä <[email protected]> According to BSpec the ring head and tail pointers must not be on the same cacheline when head > tail. The easiest way to enforce this is to reduce the reported ring space.
Signed-off-by: Ville Syrjälä <[email protected]> --- drivers/gpu/drm/i915/i915_dma.c | 2 +- drivers/gpu/drm/i915/intel_ringbuffer.c | 4 ++-- drivers/gpu/drm/i915/intel_ringbuffer.h | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 2cba7b4..d184727 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -168,7 +168,7 @@ void i915_kernel_lost_context(struct drm_device * dev) ring->head = I915_READ_HEAD(ring) & HEAD_ADDR; ring->tail = I915_READ_TAIL(ring) & TAIL_ADDR; - ring->space = ring->head - (ring->tail + 8); + ring->space = ring->head - (ring->tail + 64); if (ring->space < 0) ring->space += ring->size; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index c828169..70a184e 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -46,7 +46,7 @@ struct pipe_control { static inline int ring_space(struct intel_ring_buffer *ring) { - int space = (ring->head & HEAD_ADDR) - (ring->tail + 8); + int space = (ring->head & HEAD_ADDR) - (ring->tail + 64); if (space < 0) space += ring->size; return space; @@ -1163,7 +1163,7 @@ static int intel_ring_wait_request(struct intel_ring_buffer *ring, int n) if (request->tail == -1) continue; - space = request->tail - (ring->tail + 8); + space = request->tail - (ring->tail + 64); if (space < 0) space += ring->size; if (space >= n) { diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h index 2ea7a31..b15f896 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.h +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h @@ -187,7 +187,7 @@ void intel_cleanup_ring_buffer(struct intel_ring_buffer *ring); int __must_check intel_wait_ring_buffer(struct intel_ring_buffer *ring, int n); static inline int intel_wait_ring_idle(struct intel_ring_buffer *ring) { - return intel_wait_ring_buffer(ring, ring->size - 8); + return intel_wait_ring_buffer(ring, ring->size - 64); } int __must_check intel_ring_begin(struct intel_ring_buffer *ring, int n); -- 1.7.8.6 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
