Re: [PATCH v2 1/7] media: rkvdec: Add HEVC backend

[Jonas Karlman <jonas@kwiboo.se>]

Hi Detlev,

On 8/12/2025 10:10 PM, Detlev Casanova wrote:
> Hi Jonas,
> 
> On Sunday, 10 August 2025 17:24:31 EDT Jonas Karlman wrote:
>> The Rockchip VDEC supports the HEVC codec with the Main and Main10
>> Profile up to Level 5.1 High tier: 4096x2304@60 fps.
>>
>> Add the backend for HEVC format to the decoder.
>>
>> Signed-off-by: Alex Bee <knaerzche@gmail.com>
>> Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
>> Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
>> Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
>> ---
>> Changes in v2:
>> - Use new_value in transpose_and_flatten_matrices()
>> - Add NULL check for ctrl->new_elems in rkvdec_hevc_run_preamble()
>> - Set RKVDEC_WR_DDR_ALIGN_EN for RK3328
>> ---
>>  .../media/platform/rockchip/rkvdec/Makefile   |    2 +-
>>  .../rockchip/rkvdec/rkvdec-hevc-data.c        | 1848 +++++++++++++++++
>>  .../platform/rockchip/rkvdec/rkvdec-hevc.c    |  817 ++++++++
>>  .../platform/rockchip/rkvdec/rkvdec-regs.h    |    2 +
>>  .../media/platform/rockchip/rkvdec/rkvdec.c   |   76 +
>>  .../media/platform/rockchip/rkvdec/rkvdec.h   |    1 +
>>  6 files changed, 2745 insertions(+), 1 deletion(-)
>>  create mode 100644
>> drivers/media/platform/rockchip/rkvdec/rkvdec-hevc-data.c create mode
>> 100644 drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c
>>
> 
> [snip]
> 
>> diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c
>> b/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c new file mode 100644
>> index 000000000000..1994ea24f0be
>> --- /dev/null
>> +++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-hevc.c
> 
> [snip]
> 
>> +
>> +static enum rkvdec_image_fmt rkvdec_hevc_get_image_fmt(struct rkvdec_ctx
>> *ctx, +						       struct 
> v4l2_ctrl *ctrl)
>> +{
>> +	const struct v4l2_ctrl_hevc_sps *sps = ctrl->p_new.p_hevc_sps;
>> +
>> +	if (ctrl->id != V4L2_CID_STATELESS_HEVC_SPS)
>> +		return RKVDEC_IMG_FMT_ANY;
>> +
>> +	if (sps->bit_depth_luma_minus8 == 0) {
>> +		if (sps->chroma_format_idc == 2)
>> +			return RKVDEC_IMG_FMT_422_8BIT;
> 
> Is 4:2:2 really supported ? It is not on rk3588 and likely neither on rk3576.
> You also mention later that Only 4:0:0 and 4:2:0 are supported.

On the older rkvdec it is not, and I was unsure about the newer SoCs at
the time of initial re-work of this. Regardless this is more correct
when only looking at this function, it does not include 4:4:4 but is
correct for all currently known RKVDEC_IMG_FMT. Also to keep this
function in sync with the h264 variant for more easy compare and less
confusion about the two down the line.

Regards,
Jonas

> 
>> +		else
>> +			return RKVDEC_IMG_FMT_420_8BIT;
>> +	} else if (sps->bit_depth_luma_minus8 == 2) {
>> +		if (sps->chroma_format_idc == 2)
>> +			return RKVDEC_IMG_FMT_422_10BIT;
> 
> Same here.
> 
> --
> Detlev.
> 
> 
>