Il 18/10/22 13:41, Yunfei Dong ha scritto:
Some cavlc bistream will decode fail when the frame size is small than
s/small/smaller/g
20 bytes. Need to add pending data at the end of the bitstream. For the minimum size of mapped memory is 256 bytes(16x16), adding four bytes data won't lead to access unknown virtual memory. Fixes: 59fba9eed5a7 ("media: mediatek: vcodec: support stateless H.264 decoding for mt8192") Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx> --- compared with v1: - add detail comments for function: vdec_h264_insert_startcode. - re-write commit message. --- .../vcodec/vdec/vdec_h264_req_multi_if.c | 32 +++++++++++++++++-- 1 file changed, 29 insertions(+), 3 deletions(-) diff --git a/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c b/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c index 4cc92700692b..18e048755d11 100644 --- a/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c +++ b/drivers/media/platform/mediatek/vcodec/vdec/vdec_h264_req_multi_if.c @@ -539,6 +539,29 @@ static int vdec_h264_slice_core_decode(struct vdec_lat_buf *lat_buf) return 0; }+static void vdec_h264_insert_startcode(struct mtk_vcodec_dev *vcodec_dev, unsigned char *buf,+ size_t *bs_size, struct mtk_h264_pps_param *pps) +{ + struct device *dev = &vcodec_dev->plat_dev->dev; + + /* Need to add pending data at the end of bitstream when bs_sz is small than + * 20 bytes for cavlc bitstream, or lat will decode fail. This pending data is + * useful for mt8192 and mt8195 platform.
What is the reason why other SoCs don't need this?
+ * + * cavlc bitstream when entropy_coding_mode_flag is false. + */ + if (pps->entropy_coding_mode_flag || *bs_size > 20 || + !(of_device_is_compatible(dev->of_node, "mediatek,mt8192-vcodec-dec") || + of_device_is_compatible(dev->of_node, "mediatek,mt8195-vcodec-dec")))
I'm not comfortable seeing of_device_is_compatible... this list will grow whenever a new SoC needing this appears. Please think about a good name for a flag/quirk, or a bool, in the platform data for these two SoCs and use it. Regards, Angelo
