Re: [PATCH RFC v2 0/3] Add Amlogic stateless H.264 video decoder for S4

[Ferass El Hafidi]

Hello, quick drive-by comments:

On Mon, 24 Nov 2025 03:32, Zhentao Guo via B4 Relay <devnull+zhentao.guo.amlogic.com@xxxxxxxxxx> wrote:
> Introduce initial driver support for Amlogic's new video acceleration
> hardware architecture, designed for video stream decoding.
>
> Compared to the current Amlogic video decoder hardware architecture,
> this new implementation eliminates the Esparser hardware component,
> enabling direct vb2 buffer input. The driver is designed to support
> the V4L2 M2M stateless decoder API. The initial phase includes support
> for H.264 decoding on Amlogic S805X2 platform.
>
> The driver is capable of:
> - Supporting stateless H.264 decoding up to a resolution 1920x1088(on the S805X2 platform).

nit: 1920x1080?

> - Supporting I/P/B frame handling.
> - Supporting vb2 mmap and dma-buf modes.
> - Supporting frame-based decode mode. (Note that some H.264 bitstreams require
>  DPB reordering to generate reference lists, the stateless decoder driver
>  cannot access reordered reference lists in this mode, requiring the driver
>  to perform reference list reordering itself)
> - Supporting NV12/NV21 output.
> - Supporting Annex B start codes.

Best regards,
Ferass