[Intel-gfx] [PATCH 4/5] drm/i915: Use simplest form for flushing the single cacheline in the HWS

[Chris Wilson]

Rather than call a function to compute the matching cachelines and
clflush them, just call the clflush *instruction* directly. We also know
that we can use the unpatched plain clflush rather than the clflushopt
alternative.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala at intel.com>
Cc: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/intel_ringbuffer.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index dfb14bfe5bc8..e2b2dc2c2f49 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -393,8 +393,9 @@ intel_ring_sync_index(struct intel_engine_cs *ring,
 static inline void
 intel_flush_status_page(struct intel_engine_cs *ring, int reg)
 {
-	drm_clflush_virt_range(&ring->status_page.page_addr[reg],
-			       sizeof(uint32_t));
+	mb();
+	clflush(&ring->status_page.page_addr[reg]);
+	mb();
 }
 
 static inline u32
-- 
2.7.0