[EXT] Re: [PATCH] media: amphion: only insert the first sequence startcode for vc1l format

Tue Jul 5 05:59:11 PDT 2022

Le mardi 05 juillet 2022 à 11:27 +0000, Ming Qian a écrit :
> > > From: Ming Qian
> > > Sent: 2022年7月5日 10:00
> > > To: Nicolas Dufresne <nicolas at ndufresne.ca>; mchehab at kernel.org;
> > > hverkuil-cisco at xs4all.nl
> > > Cc: shawnguo at kernel.org; robh+dt at kernel.org; s.hauer at pengutronix.de;
> > > kernel at pengutronix.de; festevam at gmail.com; dl-linux-imx
> > > <linux-imx at nxp.com>; linux-media at vger.kernel.org;
> > > linux-kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org
> > > Subject: RE: [EXT] Re: [PATCH] media: amphion: only insert the first
> > > sequence
> > > startcode for vc1l format
> > > 
> > > > From: Nicolas Dufresne <nicolas at ndufresne.ca>
> > > > Sent: 2022年7月5日 0:06
> > > > To: Ming Qian <ming.qian at nxp.com>; mchehab at kernel.org;
> > > > hverkuil-cisco at xs4all.nl
> > > > Cc: shawnguo at kernel.org; robh+dt at kernel.org; s.hauer at pengutronix.de;
> > > > kernel at pengutronix.de; festevam at gmail.com; dl-linux-imx
> > > > <linux-imx at nxp.com>; linux-media at vger.kernel.org;
> > > > linux-kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org
> > > > Subject: [EXT] Re: [PATCH] media: amphion: only insert the first
> > > > sequence startcode for vc1l format
> > > > 
> > > > Caution: EXT Email
> > > > 
> > > > Hi Ming,
> > > > 
> > > > Le mardi 28 juin 2022 à 13:20 +0800, Ming Qian a écrit :
> > > > > For some formats, the amphion vpu requires startcode before sequence
> > > > > and frame, such as vc1, vp8.
> > > > 
> > > > I'm not sure why VP8 is being mentioned here. There is no specified
> > > > sartcode for VP8, and no split of headers either.
> > > > 
> > > 
> > > Hi Nicolas,
> > >    This patch has nothing to do with vp8, and indeed there is no specified
> > > startcode for VP8.
> > > But amphion vpu requires driver to help insert some custom startcode for
> > > vp8
> > > and vc1.
> > > It's custom behavior.
> > > 
> > Instead of exposing the custom format, you should use data_offset like VENUS
> > driver do.  They vp8/9 codec in VENUS have the frame prefixed with an IVF
> > header, the data_offset let the userland skip it.
> 
> Hi Nicolas,
>     There is a stream buffer, and driver will copy the coded frame data to the
> stream buffer, driver can decide to insert custom startcode or not, userland
> won't know about it, so I don't think it's necessary to use data_offset to let
> userland skip something.
>     Currently , driver will insert startcode for format vp8 and vc1. This is
> transparent to the user.

Can't you save the slow copy by using data_offset then ? I think most of the
confusion comes from this commit message, someone else then you should be able
to understand what it means.

regards,
Nicolas

> 
> Ming
> 
> > >    I'm sorry that my description include some confusion
> > > 
> > > Ming
> > > 
> > > > > 
> > > > > But for V4L2_PIX_FMT_VC1_ANNEX_L, only the first sequence startcode
> > > > > is needed, the extra startcode will cause decoding error.
> > > > > So after seek, we don't need to insert the sequence startcode.
> > > > > 
> > > > > In other words, for V4L2_PIX_FMT_VC1_ANNEX_L, the vpu doesn't
> > > > > support dynamic resolution change.
> > > > > 
> > > > > Fixes: 145e936380edb ("media: amphion: implement malone decoder rpc
> > > > > interface")
> > > > > Signed-off-by: Ming Qian <ming.qian at nxp.com>
> > > > > ---
> > > > >  drivers/media/platform/amphion/vdec.c       | 1 +
> > > > >  drivers/media/platform/amphion/vpu.h        | 1 +
> > > > >  drivers/media/platform/amphion/vpu_malone.c | 2 ++
> > > > >  drivers/media/platform/amphion/vpu_rpc.h    | 7 ++++++-
> > > > >  4 files changed, 10 insertions(+), 1 deletion(-)
> > > > > 
> > > > > diff --git a/drivers/media/platform/amphion/vdec.c
> > > > > b/drivers/media/platform/amphion/vdec.c
> > > > > index 09d4f27970ec..51218a41a5ac 100644
> > > > > --- a/drivers/media/platform/amphion/vdec.c
> > > > > +++ b/drivers/media/platform/amphion/vdec.c
> > > > > @@ -731,6 +731,7 @@ static void vdec_stop_done(struct vpu_inst *inst)
> > > > >       vdec->eos_received = 0;
> > > > >       vdec->is_source_changed = false;
> > > > >       vdec->source_change = 0;
> > > > > +     inst->total_input_count = 0;
> > > > >       vpu_inst_unlock(inst);
> > > > >  }
> > > > > 
> > > > > diff --git a/drivers/media/platform/amphion/vpu.h
> > > > > b/drivers/media/platform/amphion/vpu.h
> > > > > index e56b96a7e5d3..f914de6ed81e 100644
> > > > > --- a/drivers/media/platform/amphion/vpu.h
> > > > > +++ b/drivers/media/platform/amphion/vpu.h
> > > > > @@ -258,6 +258,7 @@ struct vpu_inst {
> > > > >       struct vpu_format cap_format;
> > > > >       u32 min_buffer_cap;
> > > > >       u32 min_buffer_out;
> > > > > +     u32 total_input_count;
> > > > > 
> > > > >       struct v4l2_rect crop;
> > > > >       u32 colorspace;
> > > > > diff --git a/drivers/media/platform/amphion/vpu_malone.c
> > > > > b/drivers/media/platform/amphion/vpu_malone.c
> > > > > index c62b49e85060..f4a488bf9880 100644
> > > > > --- a/drivers/media/platform/amphion/vpu_malone.c
> > > > > +++ b/drivers/media/platform/amphion/vpu_malone.c
> > > > > @@ -1314,6 +1314,8 @@ static int
> > > > vpu_malone_insert_scode_vc1_l_seq(struct malone_scode_t *scode)
> > > > >       int size = 0;
> > > > >       u8 rcv_seqhdr[MALONE_VC1_RCV_SEQ_HEADER_LEN];
> > > > > 
> > > > > +     if (scode->inst->total_input_count)
> > > > > +             return 0;
> > > > >       scode->need_data = 0;
> > > > > 
> > > > >       ret = vpu_malone_insert_scode_seq(scode,
> > > > > MALONE_CODEC_ID_VC1_SIMPLE, sizeof(rcv_seqhdr)); diff --git
> > > > > a/drivers/media/platform/amphion/vpu_rpc.h
> > > > > b/drivers/media/platform/amphion/vpu_rpc.h
> > > > > index 25119e5e807e..7eb6f01e6ab5 100644
> > > > > --- a/drivers/media/platform/amphion/vpu_rpc.h
> > > > > +++ b/drivers/media/platform/amphion/vpu_rpc.h
> > > > > @@ -312,11 +312,16 @@ static inline int vpu_iface_input_frame(struct
> > > > vpu_inst *inst,
> > > > >                                       struct vb2_buffer *vb)  {
> > > > >       struct vpu_iface_ops *ops = vpu_core_get_iface(inst->core);
> > > > > +     int ret;
> > > > > 
> > > > >       if (!ops || !ops->input_frame)
> > > > >               return -EINVAL;
> > > > > 
> > > > > -     return ops->input_frame(inst->core->iface, inst, vb);
> > > > > +     ret = ops->input_frame(inst->core->iface, inst, vb);
> > > > > +     if (ret < 0)
> > > > > +             return ret;
> > > > > +     inst->total_input_count++;
> > > > > +     return ret;
> > > > >  }
> > > > > 
> > > > >  static inline int vpu_iface_config_memory_resource(struct vpu_inst
> > > > > *inst,
> 