Re: [PATCH v5 1/2] drm/fourcc: Add NV20 and NV30 YUV formats

From: Christopher Obbard
Date: Mon Oct 23 2023 - 14:53:58 EST


Hi Jonas,

On Mon, 2023-10-23 at 17:37 +0000, Jonas Karlman wrote:
> DRM_FORMAT_NV20 and DRM_FORMAT_NV30 formats is the 2x1 and non-subsampled
> variant of NV15, a 10-bit 2-plane YUV format that has no padding between
> components. Instead, luminance and chrominance samples are grouped into 4s
> so that each group is packed into an integer number of bytes:
>
> YYYY = UVUV = 4 * 10 bits = 40 bits = 5 bytes
>
> The '20' and '30' suffix refers to the optimum effective bits per pixel
> which is achieved when the total number of luminance samples is a multiple
> of 4.
>
> V2: Added NV30 format
>
> Signed-off-by: Jonas Karlman <jonas@xxxxxxxxx>
> Reviewed-by: Sandy Huang <hjc@xxxxxxxxxxxxxx>

Reviewed-by: Christopher Obbard <chris.obbard@xxxxxxxxxxxxx>
Tested-by: Christopher Obbard <chris.obbard@xxxxxxxxxxxxx>


Cheers!

Chris

> ---
>  drivers/gpu/drm/drm_fourcc.c  | 8 ++++++++
>  include/uapi/drm/drm_fourcc.h | 2 ++
>  2 files changed, 10 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
> index 0f17dfa8702b..193cf8ed7912 100644
> --- a/drivers/gpu/drm/drm_fourcc.c
> +++ b/drivers/gpu/drm/drm_fourcc.c
> @@ -299,6 +299,14 @@ const struct drm_format_info *__drm_format_info(u32
> format)
>     .num_planes = 2, .char_per_block = { 5, 5, 0 },
>     .block_w = { 4, 2, 0 }, .block_h = { 1, 1, 0 }, .hsub =
> 2,
>     .vsub = 2, .is_yuv = true },
> + { .format = DRM_FORMAT_NV20, .depth = 0,
> +   .num_planes = 2, .char_per_block = { 5, 5, 0 },
> +   .block_w = { 4, 2, 0 }, .block_h = { 1, 1, 0 }, .hsub =
> 2,
> +   .vsub = 1, .is_yuv = true },
> + { .format = DRM_FORMAT_NV30, .depth = 0,
> +   .num_planes = 2, .char_per_block = { 5, 5, 0 },
> +   .block_w = { 4, 2, 0 }, .block_h = { 1, 1, 0 }, .hsub =
> 1,
> +   .vsub = 1, .is_yuv = true },
>   { .format = DRM_FORMAT_Q410, .depth = 0,
>     .num_planes = 3, .char_per_block = { 2, 2, 2 },
>     .block_w = { 1, 1, 1 }, .block_h = { 1, 1, 1 }, .hsub =
> 1,
> diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
> index 8db7fd3f743e..3151f1fc7ebb 100644
> --- a/include/uapi/drm/drm_fourcc.h
> +++ b/include/uapi/drm/drm_fourcc.h
> @@ -323,6 +323,8 @@ extern "C" {
>   * index 1 = Cr:Cb plane, [39:0] Cr1:Cb1:Cr0:Cb0 little endian
>   */
>  #define DRM_FORMAT_NV15 fourcc_code('N', 'V', '1', '5') /*
> 2x2 subsampled Cr:Cb plane */
> +#define DRM_FORMAT_NV20 fourcc_code('N', 'V', '2', '0') /*
> 2x1 subsampled Cr:Cb plane */
> +#define DRM_FORMAT_NV30 fourcc_code('N', 'V', '3', '0') /*
> non-subsampled Cr:Cb plane */
>  
>  /*
>   * 2 plane YCbCr MSB aligned