Re: [PATCH] media: venus: dynamic handling of bitrate

[mgottam]

On 2018-11-01 20:33, Stanimir Varbanov wrote:
> On 11/1/18 4:31 PM, Tomasz Figa wrote:
> > On Thu, Nov 1, 2018 at 11:23 PM Vikash Garodia 
> > <vgarodia@xxxxxxxxxxxxxx> wrote:
> > > On 2018-11-01 19:23, Tomasz Figa wrote:
> > > > On Thu, Nov 1, 2018 at 10:01 PM <mgottam@xxxxxxxxxxxxxx> wrote:
> > > > > On 2018-11-01 17:48, Stanimir Varbanov wrote:
> > > > > > Hi Malathi,
> > > > > >
> > > > > > Thanks for the patch!
> > > > > >
> > > > > > On 10/31/18 9:42 AM, Malathi Gottam wrote:
> > > > > > > Any request for a change in bitrate after both planes
> > > > > > > are streamed on is handled by setting the target bitrate
> > > > > > > property to hardware.
> > > > > > >
> > > > > > > Signed-off-by: Malathi Gottam <mgottam@xxxxxxxxxxxxxx>
> > > > > > > ---
> > > > > > >  drivers/media/platform/qcom/venus/venc_ctrls.c | 11 +++++++++++
> > > > > > >  1 file changed, 11 insertions(+)
> > > > > > >
> > > > > > > diff --git a/drivers/media/platform/qcom/venus/venc_ctrls.c
> > > > > > > b/drivers/media/platform/qcom/venus/venc_ctrls.c
> > > > > > > index 45910172..54f310c 100644
> > > > > > > --- a/drivers/media/platform/qcom/venus/venc_ctrls.c
> > > > > > > +++ b/drivers/media/platform/qcom/venus/venc_ctrls.c
> > > > > > > @@ -79,7 +79,9 @@ static int venc_op_s_ctrl(struct v4l2_ctrl 
> > > > > > > *ctrl)
> > > > > > >  {
> > > > > > >      struct venus_inst *inst = ctrl_to_inst(ctrl);
> > > > > > >      struct venc_controls *ctr = &inst->controls.enc;
> > > > > > > +    struct hfi_bitrate brate;
> > > > > > >      u32 bframes;
> > > > > > > +    u32 ptype;
> > > > > > >      int ret;
> > > > > > >
> > > > > > >      switch (ctrl->id) {
> > > > > > > @@ -88,6 +90,15 @@ static int venc_op_s_ctrl(struct v4l2_ctrl 
> > > > > > > *ctrl)
> > > > > > >              break;
> > > > > > >      case V4L2_CID_MPEG_VIDEO_BITRATE:
> > > > > > >              ctr->bitrate = ctrl->val;
> > > > > > > +            if (inst->streamon_out && inst->streamon_cap) {
> > > > > >
> > > > > > Hmm, hfi_session_set_property already checks the instance state so 
> > > > > > I
> > > > > > don't think those checks are needed. Another thing is that we need 
> > > > > > to
> > > > > > take the instance mutex to check the instance state.
> > > > >
> > > > > Yes Stan, "hfi_session_set_property" this property check the 
> > > > > instance
> > > > > state,
> > > > > but returns EINVAL if this is set at UNINIT instance state.
> > > > >
> > > > > Controls initialization happens much earlier than session init and
> > > > > instance init.
> > > > > So the instance is still in UNINIT state which causes failure while
> > > > > setting.
> > > > >
> > > > > Through this patch we try to meet the client request of changing
> > > > > bitrate
> > > > > only
> > > > > when both planes are streamed on.
> > > >
> > > > Where does this requirement come from? It should be possible to set
> > > > the control at any time and it should apply to any encoding 
> > > > happening
> > > > after the control is set.
> > > With the patch, now video driver will set the control whenever client
> > > sets
> > > and will apply to encoder.
> >
> > That's good, thanks for clarifying. I guess I misunderstood Malathi's 
> > comment.
>
> OK, just wonder about locking when we check streamon_out/cap flags?

Yes Stan, I agree that we should add an instance lock for these flags 
check.
Posting the updated patch. Please review.