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

[Vikash Garodia <vgarodia@codeaurora.org>]

On 2018-11-01 19:23, Tomasz Figa wrote:
> On Thu, Nov 1, 2018 at 10:01 PM <mgottam@codeaurora.org> 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@codeaurora.org>
>> >> ---
>> >>  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.

Thanks,
Vikash