[PATCH 2/4] drm/amdgpu: Fix UVD dpb min size calculation for H264

David Rosca <[email protected]> Thu, 30 Jul 2026 19:02:29 +0200
Newsgroups org.freedesktop.lists.amd-gfx
Message-ID <[email protected]>
This should use actual number of references from the decode
message, instead of maximum derived from level.

Signed-off-by: David Rosca <[email protected]>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c | 62 ++-----------------------
 1 file changed, 4 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
index 63561d1d7963..fa899e321f48 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c
@@ -646,11 +646,9 @@ static int amdgpu_uvd_cs_msg_decode(struct amdgpu_device *adev, uint32_t *msg,
 	unsigned int height = msg[7];
 	unsigned int dpb_size = msg[9];
 	unsigned int pitch = msg[28];
-	unsigned int level = msg[57];
 
 	unsigned int width_in_mb = width / 16;
 	unsigned int height_in_mb = ALIGN(height / 16, 2);
-	unsigned int fs_in_mb = width_in_mb * height_in_mb;
 
 	unsigned int image_size, tmp, min_dpb_size, num_dpb_buffer;
 	unsigned int min_ctx_size = ~0;
@@ -669,35 +667,9 @@ static int amdgpu_uvd_cs_msg_decode(struct amdgpu_device *adev, uint32_t *msg,
 
 	switch (stream_type) {
 	case 0: /* H264 */
-		switch (level) {
-		case 30:
-			num_dpb_buffer = 8100 / fs_in_mb;
-			break;
-		case 31:
-			num_dpb_buffer = 18000 / fs_in_mb;
-			break;
-		case 32:
-			num_dpb_buffer = 20480 / fs_in_mb;
-			break;
-		case 41:
-			num_dpb_buffer = 32768 / fs_in_mb;
-			break;
-		case 42:
-			num_dpb_buffer = 34816 / fs_in_mb;
-			break;
-		case 50:
-			num_dpb_buffer = 110400 / fs_in_mb;
-			break;
-		case 51:
-			num_dpb_buffer = 184320 / fs_in_mb;
-			break;
-		default:
-			num_dpb_buffer = 184320 / fs_in_mb;
-			break;
-		}
-		num_dpb_buffer++;
+		num_dpb_buffer = ((msg[61] >> 16) & 0xff) + 1;
 		if (num_dpb_buffer > 17)
-			num_dpb_buffer = 17;
+			return -EINVAL;
 
 		/* reference picture buffer */
 		min_dpb_size = image_size * num_dpb_buffer;
@@ -747,35 +719,9 @@ static int amdgpu_uvd_cs_msg_decode(struct amdgpu_device *adev, uint32_t *msg,
 		break;
 
 	case 7: /* H264 Perf */
-		switch (level) {
-		case 30:
-			num_dpb_buffer = 8100 / fs_in_mb;
-			break;
-		case 31:
-			num_dpb_buffer = 18000 / fs_in_mb;
-			break;
-		case 32:
-			num_dpb_buffer = 20480 / fs_in_mb;
-			break;
-		case 41:
-			num_dpb_buffer = 32768 / fs_in_mb;
-			break;
-		case 42:
-			num_dpb_buffer = 34816 / fs_in_mb;
-			break;
-		case 50:
-			num_dpb_buffer = 110400 / fs_in_mb;
-			break;
-		case 51:
-			num_dpb_buffer = 184320 / fs_in_mb;
-			break;
-		default:
-			num_dpb_buffer = 184320 / fs_in_mb;
-			break;
-		}
-		num_dpb_buffer++;
+		num_dpb_buffer = ((msg[61] >> 16) & 0xff) + 1;
 		if (num_dpb_buffer > 17)
-			num_dpb_buffer = 17;
+			return -EINVAL;
 
 		/* reference picture buffer */
 		min_dpb_size = image_size * num_dpb_buffer;
-- 
2.43.0