1 files changed, 14 insertions, 6 deletions

diff --git a/drivers/gpu/drm/radeon/cik_sdma.c b/drivers/gpu/drm/radeon/cik_sdma.c
index d7e51c06d597..9abea87a9213 100644
--- a/drivers/gpu/drm/radeon/cik_sdma.c
+++ b/drivers/gpu/drm/radeon/cik_sdma.c
@@ -168,13 +168,21 @@ static void cik_sdma_hdp_flush_ring_emit(struct radeon_device *rdev,
                                          int ridx)
 {
         struct radeon_ring *ring = &rdev->ring[ridx];
+        u32 extra_bits = (SDMA_POLL_REG_MEM_EXTRA_OP(1) |
+                          SDMA_POLL_REG_MEM_EXTRA_FUNC(3)); /* == */
+        u32 ref_and_mask;
 
-        /* We should be using the new POLL_REG_MEM special op packet here
-         * but it causes sDMA to hang sometimes
-         */
-        radeon_ring_write(ring, SDMA_PACKET(SDMA_OPCODE_SRBM_WRITE, 0, 0xf000));
-        radeon_ring_write(ring, HDP_MEM_COHERENCY_FLUSH_CNTL >> 2);
-        radeon_ring_write(ring, 0);
+        if (ridx == R600_RING_TYPE_DMA_INDEX)
+                ref_and_mask = SDMA0;
+        else
+                ref_and_mask = SDMA1;
+
+        radeon_ring_write(ring, SDMA_PACKET(SDMA_OPCODE_POLL_REG_MEM, 0, extra_bits));
+        radeon_ring_write(ring, GPU_HDP_FLUSH_DONE);
+        radeon_ring_write(ring, GPU_HDP_FLUSH_REQ);
+        radeon_ring_write(ring, ref_and_mask); /* reference */
+        radeon_ring_write(ring, ref_and_mask); /* mask */
+        radeon_ring_write(ring, (0xfff << 16) | 10); /* retry count, poll interval */
 }
 
 /**