[Intel-gfx] [PATCH] drm/i915: Flush pipecontrol post-sync writes

[Chris Wilson]

In order to flush the results from in-batch pipecontrol writes (used for
example in glQuery) before declaring the batch complete (and so declaring
the query results coherent), we need to set the FlushEnable bit in our
flushing pipecontrol. The FlushEnable bit "waits until all previous
writes of immediate data from post-sync circles are complete before
executing the next command".

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: stable at vger.kernel.org
---
 drivers/gpu/drm/i915/intel_lrc.c        | 1 +
 drivers/gpu/drm/i915/intel_ringbuffer.c | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 01cf0ca21990..e0c19d75b196 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -1771,6 +1771,7 @@ static int gen8_emit_flush_render(struct drm_i915_gem_request *request,
 	if (flush_domains) {
 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+		flags |= PIPE_CONTROL_FLUSH_ENABLE;
 	}
 
 	if (invalidate_domains) {
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index c2392f6c4204..551af7399ca1 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -330,6 +330,7 @@ gen7_render_ring_flush(struct drm_i915_gem_request *req,
 	if (flush_domains) {
 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+		flags |= PIPE_CONTROL_FLUSH_ENABLE;
 	}
 	if (invalidate_domains) {
 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
@@ -401,6 +402,7 @@ gen8_render_ring_flush(struct drm_i915_gem_request *req,
 	if (flush_domains) {
 		flags |= PIPE_CONTROL_RENDER_TARGET_CACHE_FLUSH;
 		flags |= PIPE_CONTROL_DEPTH_CACHE_FLUSH;
+		flags |= PIPE_CONTROL_FLUSH_ENABLE;
 	}
 	if (invalidate_domains) {
 		flags |= PIPE_CONTROL_TLB_INVALIDATE;
-- 
2.5.0