Re: [PATCH v2 0/3] media: rockchip: rkvdec: add support for the VDPU346 variant

[Dang Huynh <dang.huynh@mainlining.org>]

Hi Christian,

On Friday, December 26, 2025 11:31:37 AM Coordinated Universal Time Christian 
Hewitt wrote:
> This series depends upon Detlev Casanova's current v7 series for VDPU381 and
> VDPU383 support [0]. It adds support for the VDPU346 IP block used for
> H264, HEVC and (in active work) VP9 on the RK356X boards. VDPU346 appears
> to be a close relation to VDPU381 used with RK3588, except with a single
> core, output limited to 4K, and minor feature differences, e.g. HEVC level
> 5.1 on VDPU346 vs 6.1 on VDPU381. To handle differences we declare a new
> compatible.
> 
> The device-tree changes are derived from prior-art in Detlev's patches for
> RK3576 and RK3588, the vendor kernel [1], and some earlier patch attempts
> from Piotr Oniszczuk and Diederik de Haas.
> 
> The register differences between VDPU346 and VDPU381 appear to be minimal so
> we currently and intentionally reuse the VDPU381 h264, hevc, and regs files
> to avoid duplicating code. There is some evidence of buffer size changes in
> testing which still need to be explored. If further register analysis needs
> separate files for VDPU346 the refactoring will be beyond my current n00b
> coding skills and I will either need some coaching or would be happy to
> pass the series over to a more experienced developer.
> 
> NB: Testing with the v1 series showed lower mbps bitrate performance. This
> appears to be resolved though it's unclear to me whether this results from
> kernel changes or the ongoing reworking of ffmpeg v4l2_request support [2].
> However with my current Linux 6.19-rc2 test branch [3] I'm now able to play
> Jellyfish H264 and HEVC test media over 100mbps.
> 
> Changes since v1:
> - Drop DO-NOT-MERGE patch as changes included in Detvlev v7 series
> - Adapt to variant/capability changes in Detlev's v7 series
> - Add bindings ack from Rob
> - Add rkvdec ack from Nicolas
> - Rebase against Linux 6.19-rc2
> 
> [0] https://patchwork.kernel.org/project/linux-rockchip/list/?series=1034794
> [1]
> https://github.com/rockchip-linux/kernel/blob/develop-6.6/arch/arm64/boot/d
> ts/rockchip/rk356x.dtsi#L1539 [2]
> https://code.ffmpeg.org/Kwiboo/FFmpeg/commits/branch/v4l2request-v3 [3]
> https://github.com/chewitt/linux/commits/rockchip-6.19.y
> 
> Christian Hewitt (3):
>   media: dt-bindings: rockchip: Add RK3568 Video Decoder bindings
>   media: rkvdec: Add support for the VDPU346 variant
>   arm64: dts: rockchip: Add the vdpu346 Video Decoders on RK356X
> 
>  .../bindings/media/rockchip,vdec.yaml         |   2 +
>  arch/arm64/boot/dts/rockchip/rk356x-base.dtsi |  49 +++++++++
>  .../media/platform/rockchip/rkvdec/rkvdec.c   | 103 ++++++++++++++++++
>  3 files changed, 154 insertions(+)

I tested this patch series on my RK3566 board with my own test videos and BBB 
(1080p60 and 4k30) using mpv with [1] patchset.

The command I used was:
`mpv --vo=dmabuf-wayland --hwdec=v4l2request input_file.mp4`

Both H264 and HEVC plays with minor framedrops (which to me isn't noticeable).

You can add my Tested-by:
Tested-by: Dang Huynh <dang.huynh@mainlining.org>

[1]: https://github.com/mpv-player/mpv/pull/14690

Best regards,
Dang