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

From: Hans Verkuil
Date: Mon Aug 07 2023 - 07:12:19 EST


FYI: the v2 patch has already been merged, so I dropped this v3.

On 03/08/2023 13:10, Xiaoyong Lu wrote:
> 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@xxxxxxxxxxxx>
> ---
> Changes from v2:
>
> - refine commit subject and message

It's only subject/commit message changes, the actual code is the same.

Regards,

Hans

>
> 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) &