[PATCH 09/19] drm/amdgpu/ring: add helper for padding the ring

[Alex Deucher]

Add a helper to pad the ring to a multiple of the fetch size.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 29 +++++++++++++++++-------
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h |  1 +
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 426834806fbf2..6a13ef9145447 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -141,21 +141,17 @@ void amdgpu_ring_generic_pad_ib(struct amdgpu_ring *ring, struct amdgpu_ib *ib)
 }
 
 /**
- * amdgpu_ring_commit - tell the GPU to execute the new
- * commands on the ring buffer
+ * amdgpu_ring_pad_to_fetch_size - pad the ring with nops
+ * to the fetch size.
  *
  * @ring: amdgpu_ring structure holding ring information
  *
- * Update the wptr (write pointer) to tell the GPU to
- * execute new commands on the ring buffer (all asics).
+ * Pad the ring with nops to align with the hardware fetch size.
  */
-void amdgpu_ring_commit(struct amdgpu_ring *ring)
+void amdgpu_ring_pad_to_fetch_size(struct amdgpu_ring *ring)
 {
 	uint32_t count;
 
-	if (ring->count_dw < 0)
-		DRM_ERROR("amdgpu: writing more dwords to the ring than expected!\n");
-
 	/* We pad to match fetch size */
 	count = ring->funcs->align_mask + 1 -
 		(ring->wptr & ring->funcs->align_mask);
@@ -163,6 +159,23 @@ void amdgpu_ring_commit(struct amdgpu_ring *ring)
 
 	if (count != 0)
 		ring->funcs->insert_nop(ring, count);
+}
+
+/**
+ * amdgpu_ring_commit - tell the GPU to execute the new
+ * commands on the ring buffer
+ *
+ * @ring: amdgpu_ring structure holding ring information
+ *
+ * Update the wptr (write pointer) to tell the GPU to
+ * execute new commands on the ring buffer (all asics).
+ */
+void amdgpu_ring_commit(struct amdgpu_ring *ring)
+{
+	if (ring->count_dw < 0)
+		DRM_ERROR("amdgpu: writing more dwords to the ring than expected!\n");
+
+	amdgpu_ring_pad_to_fetch_size(ring);
 
 	mb();
 	amdgpu_ring_set_wptr(ring);
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
index b95b471107692..235af37145dd3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
@@ -421,6 +421,7 @@ void amdgpu_ring_ib_on_emit_de(struct amdgpu_ring *ring);
 
 void amdgpu_ring_insert_nop(struct amdgpu_ring *ring, uint32_t count);
 void amdgpu_ring_generic_pad_ib(struct amdgpu_ring *ring, struct amdgpu_ib *ib);
+void amdgpu_ring_pad_to_fetch_size(struct amdgpu_ring *ring);
 void amdgpu_ring_commit(struct amdgpu_ring *ring);
 void amdgpu_ring_undo(struct amdgpu_ring *ring);
 int amdgpu_ring_init(struct amdgpu_device *adev, struct amdgpu_ring *ring,
-- 
2.49.0