Re: [PATCH v6 09/17] media: uapi: HEVC: Define V4L2_CID_STATELESS_HEVC_SLICE_PARAMS as a dynamic array

Benjamin Gaignard
2022-06-01T16:03:02Z

Le 01/06/2022 à 17:43, Jernej Škrabec a écrit :
> Dne nedelja, 29. maj 2022 ob 11:19:12 CEST je Jernej Škrabec napisal(a):
>> Dne petek, 27. maj 2022 ob 16:31:26 CEST je Benjamin Gaignard napisal(a):
>>> Make explicit that V4L2_CID_STATELESS_HEVC_SLICE_PARAMS control is
>>> a dynamic array control type.
>>> Some drivers may be able to receive multiple slices in one control
>>> to improve decoding performance.
>>>
>>> Define the max size of the dynamic that can driver can set in .dims = {}.
>>>
>>> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
>>> ---
>>> version 6:
>>> - Set V4L2_CTRL_FLAG_DYNAMIC_ARRAY flag automatically when using
>>> V4L2_CID_STATELESS_HEVC_SLICE_PARAMS control.
>>> - Add a define for max slices count
>>>
>>> Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst | 2 ++
>>> drivers/media/v4l2-core/v4l2-ctrls-defs.c | 1 +
>>> include/media/hevc-ctrls.h | 5 +++++
>>> 3 files changed, 8 insertions(+)
>>>
>>> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst b/
>> Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>>> index 06b967de140c..0796b1563daa 100644
>>> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>>> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-codec.rst
>>> @@ -2986,6 +2986,8 @@ enum v4l2_mpeg_video_hevc_size_of_length_field -
>>> These bitstream parameters are defined according to :ref:`hevc`.
>>> They are described in section 7.4.7 "General slice segment header
>>> semantics" of the specification.
>>> + This control is a dynamically sized 1-dimensional array,
>>> + V4L2_CTRL_FLAG_DYNAMIC_ARRAY flag must be set when using it.
>>>
>>> .. c:type:: v4l2_ctrl_hevc_slice_params
>>>
>>> diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/
> v4l2-
>> core/v4l2-ctrls-defs.c
>>> index 9f55503cd3d6..d594efbcbb93 100644
>>> --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
>>> +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
>>> @@ -1510,6 +1510,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum
>> v4l2_ctrl_type *type,
>>> break;
>>> case V4L2_CID_STATELESS_HEVC_SLICE_PARAMS:
>>> *type = V4L2_CTRL_TYPE_HEVC_SLICE_PARAMS;
>>> + *flags |= V4L2_CTRL_FLAG_DYNAMIC_ARRAY;
>> This change breaks Cedrus. I'll check what needs to be changed.
> Please include the change bellow to keep Cedrus working. I'll expand support
> for more slices later.

That will be in version 7. Thanks.
I will wait for more reviews on the others patches before send it.

Regards,
Benjamin

>
> Best regards,
> Jernej
>
> --- a/drivers/staging/media/sunxi/cedrus/cedrus.c
> +++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
> @@ -178,6 +178,7 @@ static const struct cedrus_control cedrus_controls[] = {
> {
> .cfg = {
> .id = V4L2_CID_STATELESS_HEVC_SLICE_PARAMS,
> + .dims = { 1 },
> },
> .codec = CEDRUS_CODEC_H265,
> },
>
>>> break;
>>> case V4L2_CID_STATELESS_HEVC_SCALING_MATRIX:
>>> *type = V4L2_CTRL_TYPE_HEVC_SCALING_MATRIX;
>>> diff --git a/include/media/hevc-ctrls.h b/include/media/hevc-ctrls.h
>>> index 0dbd5d681c28..140151609c96 100644
>>> --- a/include/media/hevc-ctrls.h
>>> +++ b/include/media/hevc-ctrls.h
>>> @@ -311,9 +311,14 @@ struct v4l2_hevc_pred_weight_table {
>>> #define
> V4L2_HEVC_SLICE_PARAMS_FLAG_SLICE_LOOP_FILTER_ACROSS_SLICES_ENABLED
>> (1ULL << 8)
>>> #define V4L2_HEVC_SLICE_PARAMS_FLAG_DEPENDENT_SLICE_SEGMENT (1ULL <<
>> 9)
>>>
>>> +#define V4L2_HEVC_SLICE_MAX_COUNT 600
>>> +
>>> /**
>>> * v4l2_ctrl_hevc_slice_params - HEVC slice parameters
>>> *
>>> + * This control is a dynamically sized 1-dimensional array,
>>> + * V4L2_CTRL_FLAG_DYNAMIC_ARRAY flag must be set when using it.
>>> + *
>>> * @bit_size: size (in bits) of the current slice data
>>> * @data_bit_offset: offset (in bits) to the video data in the current
> slice
>> data
>>> * @nal_unit_type: specifies the coding type of the slice (B, P or I)
>>> --
>>> 2.32.0
>>>
>>>
>>
>>
>