drm/amdgpu: drop volatile from ring buffer

Volatile only prevents the compiler from re-ordering reads and writes.
Since we always only modify the ring buffer from one CPU thread and have
an explicit barrier before signaling the HW this should have no effect at
all and just prevents compiler optimisations.

While at it drop the local variables as well.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Sunil Khatri <sunil.khatri@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 3 insertions, 7 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 42f616c05f50..a6e28fe3f8d6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -109,21 +109,17 @@ int amdgpu_ring_alloc(struct amdgpu_ring *ring, unsigned int ndw)
 void amdgpu_ring_insert_nop(struct amdgpu_ring *ring, uint32_t count)
 {
 	uint32_t occupied, chunk1, chunk2;
-	uint32_t *dst;
 
 	occupied = ring->wptr & ring->buf_mask;
-	dst = (void *)&ring->ring[occupied];
 	chunk1 = ring->buf_mask + 1 - occupied;
 	chunk1 = (chunk1 >= count) ? count : chunk1;
 	chunk2 = count - chunk1;
 
 	if (chunk1)
-		memset32(dst, ring->funcs->nop, chunk1);
+		memset32(&ring->ring[occupied], ring->funcs->nop, chunk1);
 
-	if (chunk2) {
-		dst = (void *)ring->ring;
-		memset32(dst, ring->funcs->nop, chunk2);
-	}
+	if (chunk2)
+		memset32(ring->ring, ring->funcs->nop, chunk2);
 
 	ring->wptr += count;
 	ring->wptr &= ring->ptr_mask;