Hi Hans,
On 03/27/2017 11:45 AM, Hans Verkuil wrote:
> On 25/03/17 23:30, Stanimir Varbanov wrote:
>> Thanks for the comments!
<snip>
>>>> +static void vdec_buf_done(struct venus_inst *inst, unsigned int buf_type,
>>>> + u32 tag, u32 bytesused, u32 data_offset, u32 flags,
>>>> + u64 timestamp_us)
>>>> +{
>>>> + struct vb2_v4l2_buffer *vbuf;
>>>> + struct vb2_buffer *vb;
>>>> + unsigned int type;
>>>> +
>>>> + if (buf_type == HFI_BUFFER_INPUT)
>>>> + type = V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE;
>>>> + else
>>>> + type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
>>>> +
>>>> + vbuf = helper_find_buf(inst, type, tag);
>>>> + if (!vbuf)
>>>> + return;
>>>> +
>>>> + vbuf->flags = flags;
>>>> +
>>>> + if (type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE) {
>>>> + vb = &vbuf->vb2_buf;
>>>> + vb->planes[0].bytesused =
>>>> + max_t(unsigned int, inst->output_buf_size, bytesused);
>>>> + vb->planes[0].data_offset = data_offset;
>>>> + vb->timestamp = timestamp_us * NSEC_PER_USEC;
>>>> + vbuf->sequence = inst->sequence++;
>>>
>>> timestamp and sequence are only set for CAPTURE, not OUTPUT. Is that correct?
>>
>> Correct. I can add sequence for the OUTPUT queue too, but I have no idea how that sequence is used by userspace.
>
> You set V4L2_BUF_FLAG_TIMESTAMP_COPY, so you have to copy the timestamp from the output buffer
> to the capture buffer, if that makes sense for this codec. If not, then you shouldn't use that
The timestamp_us is filled by firmware and it is the timestamp of the
output buffer which is used to produce the uncompressed capture buffer.
So I think V4L2_BUF_FLAG_TIMESTAMP_COPY is correctly used here.
> V4L2_BUF_FLAG and just generate new timestamps whenever a capture buffer is ready.
>
> For sequence numbering just give the output queue its own sequence counter.
OK will do.
--
regards,
Stan
