[Intel-gfx] [PATCH 7/8] drm/i915: PIPE_CONTROL TLB invalidate requires CS stall

[Jesse Barnes]

"If ENABLED, PIPE_CONTROL command will flush the in flight data  written
out by render engine to Global Observation point on flush done. Also
Requires stall bit ([20] of DW1) set."

So set the stall bit to ensure proper invalidation.

Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
 drivers/gpu/drm/i915/intel_ringbuffer.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index e7daa90..1e09c62 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -246,7 +246,7 @@ gen6_render_ring_flush(struct intel_ring_buffer *ring,
 		/*
 		 * TLB invalidate requires a post-sync write.
 		 */
-		flags |= PIPE_CONTROL_QW_WRITE;
+		flags |= PIPE_CONTROL_QW_WRITE | PIPE_CONTROL_CS_STALL;
 	}
 
 	ret = intel_ring_begin(ring, 4);
-- 
1.7.9.5