[v3] media: mediatek: vcodec: fix AV1 decoding on MT8188

Xiaoyong Lu xiaoyong.lu at mediatek.com
Thu Aug 3 04:10:17 PDT 2023


Fix AV1 decoding failure when the iova is 36bit.

Before this fix, the decoder was accessing incorrect addresses with 36bit
iova tile buffer, leading to iommu faults.

Fixes: 2f5d0aef37c6 ("media: mediatek: vcodec: support stateless AV1 decoder")
Signed-off-by: Xiaoyong Lu<xiaoyong.lu at mediatek.com>
---
Changes from v2:

- refine commit subject and message

Changes from v1:

- prefer '|' rather than '+'
- prefer '&' rather than shift operation
- add comments for address operations

v1:
- VDEC HW can access tile buffer and decode normally.
- Test ok by mt8195 32bit and mt8188 36bit iova.

---
 .../mediatek/vcodec/vdec/vdec_av1_req_lat_if.c       | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/mediatek/vcodec/vdec/vdec_av1_req_lat_if.c b/drivers/media/platform/mediatek/vcodec/vdec/vdec_av1_req_lat_if.c
index 404a1a23fd402..e9f2393f6a883 100644
--- a/drivers/media/platform/mediatek/vcodec/vdec/vdec_av1_req_lat_if.c
+++ b/drivers/media/platform/mediatek/vcodec/vdec/vdec_av1_req_lat_if.c
@@ -1658,9 +1658,9 @@ static void vdec_av1_slice_setup_tile_buffer(struct vdec_av1_slice_instance *ins
 	u32 allow_update_cdf = 0;
 	u32 sb_boundary_x_m1 = 0, sb_boundary_y_m1 = 0;
 	int tile_info_base;
-	u32 tile_buf_pa;
+	u64 tile_buf_pa;
 	u32 *tile_info_buf = instance->tile.va;
-	u32 pa = (u32)bs->dma_addr;
+	u64 pa = (u64)bs->dma_addr;
 
 	if (uh->disable_cdf_update == 0)
 		allow_update_cdf = 1;
@@ -1673,8 +1673,12 @@ static void vdec_av1_slice_setup_tile_buffer(struct vdec_av1_slice_instance *ins
 		tile_info_buf[tile_info_base + 0] = (tile_group->tile_size[tile_num] << 3);
 		tile_buf_pa = pa + tile_group->tile_start_offset[tile_num];
 
-		tile_info_buf[tile_info_base + 1] = (tile_buf_pa >> 4) << 4;
-		tile_info_buf[tile_info_base + 2] = (tile_buf_pa % 16) << 3;
+		/* save av1 tile high 4bits(bit 32-35) address in lower 4 bits position
+		 * and clear original for hw requirement.
+		 */
+		tile_info_buf[tile_info_base + 1] = (tile_buf_pa & 0xFFFFFFF0ull) |
+			((tile_buf_pa & 0xF00000000ull) >> 32);
+		tile_info_buf[tile_info_base + 2] = (tile_buf_pa & 0xFull) << 3;
 
 		sb_boundary_x_m1 =
 			(tile->mi_col_starts[tile_col + 1] - tile->mi_col_starts[tile_col] - 1) &
-- 
2.18.0




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