[PATCH] media: mediatek: vcodec: Handle VP9 superframe bitstream with 8 sub-frames

[Irui Wang (王瑞)]

Dear Nicolas,

Thanks for your reviewing.
Yes, this patch is just for the VP9 stateful decoder process, so the
super frame is handled in stateful driver.

On Mon, 2024-02-19 at 16:09 -0500, Nicolas Dufresne wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  Hi,
> 
> Le dimanche 18 février 2024 à 19:59 +0800, Irui Wang a écrit :
> > The VP9 bitstream has 8 sub-frames into one superframe, the
> superframe
> > index validate failed when reach 8, modify the index checking so
> that the
> > last sub-frame can be decoded normally.
> 
> When I first saw this patch I was concerned, since we don't allow
> bundling super
> frame into the stateless API, but now I realize that this is for the
> stateful
> decoder. Perhaps you can help me and possibly other reviewers with
> simply
> stating that this is for stateful decoders.
> 
> > 
> > Signed-off-by: Irui Wang <irui.wang at mediatek.com>
> > ---
> >  .../media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_if.c | 4
> ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git
> a/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_if.c
> b/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_if.c
> > index 55355fa70090..4a9ced7348ee 100644
> > ---
> a/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_if.c
> > +++
> b/drivers/media/platform/mediatek/vcodec/decoder/vdec/vdec_vp9_if.c
> > @@ -526,7 +526,7 @@ static void vp9_swap_frm_bufs(struct
> vdec_vp9_inst *inst)
> >  /* if this super frame and it is not last sub-frame, get next fb
> for
> >   * sub-frame decode
> >   */
> > -if (vsi->sf_frm_cnt > 0 && vsi->sf_frm_idx != vsi->sf_frm_cnt - 1)
> > +if (vsi->sf_frm_cnt > 0 && vsi->sf_frm_idx != vsi->sf_frm_cnt)
> >  vsi->sf_next_ref_fb_idx = vp9_get_sf_ref_fb(inst);
> >  }
> >  
> > @@ -735,7 +735,7 @@ static void get_free_fb(struct vdec_vp9_inst
> *inst, struct vdec_fb **out_fb)
> >  
> >  static int validate_vsi_array_indexes(struct vdec_vp9_inst *inst,
> >  struct vdec_vp9_vsi *vsi) {
> > -if (vsi->sf_frm_idx >= VP9_MAX_FRM_BUF_NUM - 1) {
> > +if (vsi->sf_frm_idx >= VP9_MAX_FRM_BUF_NUM) {
> 
> nit: I'd propose to define a new maximum (contractions allowed):
> 
>   #define VP9_MAX_NUM_SUPER_FRAMES 8
> 
> This way you can revisit bunch of `VP9_MAX_FRM_BUF_NUM-1`, and make
> the overall
> code a bit more human readable. There is no relation between
> VP9_MAX_FRM_BUF_NUM
> and this maximum. The limits simply comes from the fact
> frames_in_superframe_minus_1 is expressed with 3 bits.
> 
> regards,
> Nicolas
> 
Yes, define a new maximum makes code more readable, we will check it.

Thanks
Best Regards

> p.s. your change looks good otherwise.
> 
> >  mtk_vdec_err(inst->ctx, "Invalid vsi->sf_frm_idx=%u.", vsi-
> >sf_frm_idx);
> >  return -EIO;
> >  }
>