[PATCH 09/12] media: hantro: Enable H.264 on Rockchip VDPU2

[Alex Bee]

Hi Ezequiel,

Am 29.06.21 um 14:28 schrieb Ezequiel Garcia:
> Hi Alex,
>
> On Sat, 2021-06-26 at 10:33 +0200, Alex Bee wrote:
>> Hi Ezequiel,
>>
>> Am 26.06.21 um 02:46 schrieb Ezequiel Garcia:
>>> (Adding Nicolas)
>>>
>>> Hi Alex,
>>>
>>> On Fri, 2021-06-25 at 01:13 +0200, Alex Bee wrote:
>>>> Hi Ezequiel,
>>>>
>>>> Am 24.06.21 um 20:26 schrieb Ezequiel Garcia:
>>>>> Given H.264 support for VDPU2 was just added, let's enable it.
>>>>> For now, this is only enabled on platform that don't have
>>>>> an RKVDEC core, such as RK3328.
>>>> Is there any reason, you do not want to enabe H.264 on RK3399? I know
>>>> H.264 can be done by by rkvdec already, but from what I understand that
>>>> shouldn't be an issue: The first decoder found that meets the
>>>> requirements will be taken.
>>>>
>>> Thanks a lot the review.
>>>
>>> I really doubt userspace stacks are readily supporting that strategy.
>>>
>>> The first decoder device supporting the codec format will be selected,
>>> I doubt features such as profile and levels are checked to decide
>>> which decoder to use.
>>>
>>> I'd rather play safe on the kernel side and avoid offering
>>> two competing devices for the same codec.
>> I wasn't aware of that. Current ffmpeg v4l2_request implementation seems
>> to not do VIDIOC_ENUM_FRAMESIZES - so we might end up being able to
>> decode up to 1920x1088 only if hantro decoder is picked/checked first.
>>
> Speaking of ffmpeg, now that MPEG-2, VP8 and H.264 control interfaces
> are stable, I think one of the next priorities would be to push Jonas'
> ffmpeg patches.
>
> It would be really cool if someone could take the lead on that front,
> as it would reduce kodi's out of tree stack, enable mpv, and so on.

That's absolutely true.

Note that Jonas himself started upstreaming those patches right after 
H264 uapi got stable [1].

Unfortunately I'm the absolut wrong person for doing/continuing this, 
since the very first time I ever looked at the implementation details 
was just for the response I wrote here. So I asked Jernej whos know all 
the details and contributed to those patches as well - he told me he'll 
continue whenever he finds time next.

Best,

Alex

[1] https://patchwork.ffmpeg.org/project/ffmpeg/list/?series=2898