Re: [PATCH 0/4] Add V4L2_PIX_FMT_MT21C format for MT8173 codec driver

[Tiffany Lin]

Hi Hans,

On Thu, 2016-09-08 at 09:21 +0200, Hans Verkuil wrote:
> Hi Tiffany,
> 
> On 09/07/2016 08:56 AM, Tiffany Lin wrote:
> > This patch series add Mediatek compressed block format V4L2_PIX_FMT_MT21C, the
> > decoder driver will decoded bitstream to V4L2_PIX_FMT_MT21C format.
> > 
> > User space applications could use MT8173 MDP driver to convert V4L2_PIX_FMT_MT21C to
> > V4L2_PIX_FMT_NV12M, V4L2_PIX_FMT_YUV420M and V4L2_PIX_FMT_YVU420.
> > 
> > MDP driver[1] is stand alone driver.
> > 
> > Usage:
> > MT21C -> MT8173 MDP -> NV12M/YUV420M/YVU420
> > NV12M/NV21M/YUV420M/YVU420M -> mt8173 Encoder -> H264/VP8
> > H264/VP8/VP9 -> mtk8173 Decoder -> MT21C
> > 
> > When encode with MT21 source, the pipeline will be:
> > MT21C -> MDP driver-> NV12M/NV21M/YUV420M/YVU420M -> Encoder -> H264/VP8
> > 
> > When playback, the pipeline will be:
> > H264/VP8/VP9 -> Decoder driver -> MT21C -> MDP Driver -> DRM
> > 
> > [1]https://patchwork.kernel.org/patch/9305329/
> > 
> > Tiffany Lin (4):
> >   v4l: add Mediatek compressed video block format
> >   docs-rst: Add compressed video formats used on MT8173 codec driver
> >   vcodec: mediatek: Add V4L2_PIX_FMT_MT21C support for v4l2 decoder
> >   arm64: dts: mediatek: Add Video Decoder for MT8173
> > 
> >  Documentation/media/uapi/v4l/pixfmt-reserved.rst   |    6 +++
> >  arch/arm64/boot/dts/mediatek/mt8173.dtsi           |   44 ++++++++++++++++++++
> >  drivers/media/platform/mtk-vcodec/mtk_vcodec_dec.c |    7 +++-
> >  drivers/media/v4l2-core/v4l2-ioctl.c               |    1 +
> >  include/uapi/linux/videodev2.h                     |    1 +
> >  5 files changed, 58 insertions(+), 1 deletion(-)
> > 
> 
> So basically the video decoder is useless without support for this format and
> without the MDP driver, right?
> 
Yes. It also require new vpu firmware.
Andrew will help release new vpu firmware include encode/decode/mdp
capability.

best regards,
Tiffany


> I'm wondering if I should hold off on merging the decoder driver until these two
> are in. What is the timeline for v6 of the MDP driver?
> 
> If a v6 is posted early next week, then I have time to review and (assuming it is
> OK) I can make a pull request for both this driver and the MDP driver.
> 
> If it takes longer, then there is a good chance that it will slip to 4.10. I will
> have very little time in the period September 20 - October 14.
> 
> Regards,
> 
> 	Hans