Re: [PATCH v2 5/7] drm/vkms: Add YUV support

[Louis Chauvet <louis.chauvet@bootlin.com>]

Le 10/01/24 - 14:44, Arthur Grillo a écrit :
> Add support to the YUV formats bellow:
> 
> - NV12
> - NV16
> - NV24
> - NV21
> - NV61
> - NV42
> - YUV420
> - YUV422
> - YUV444
> - YVU420
> - YVU422
> - YVU444
> 
> The conversion matrices of each encoding and range were obtained by
> rounding the values of the original conversion matrices multiplied by
> 2^8. This is done to avoid the use of fixed point operations.
> 
> Signed-off-by: Arthur Grillo <arthurgrillo@riseup.net>
> ---
>  drivers/gpu/drm/vkms/vkms_formats.c | 147 ++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/vkms/vkms_formats.h |   4 +
>  drivers/gpu/drm/vkms/vkms_plane.c   |  14 +++-
>  3 files changed, 164 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
> index 098ed16f2104..7c1a0ca322d9 100644
> --- a/drivers/gpu/drm/vkms/vkms_formats.c
> +++ b/drivers/gpu/drm/vkms/vkms_formats.c
> @@ -119,6 +119,137 @@ static void RGB565_to_argb_u16(u8 **src_pixels, struct pixel_argb_u16 *out_pixel
>  	out_pixel->b = drm_fixp2int_round(drm_fixp_mul(fp_b, fp_rb_ratio));
>  }
>  
> +static void ycbcr2rgb(const s16 m[3][3], u8 y, u8 cb, u8 cr, u8 y_offset, u8 *r, u8 *g, u8 *b)
> +{
> +	s32 y_16, cb_16, cr_16;
> +	s32 r_16, g_16, b_16;
> +
> +	y_16 =  y - y_offset;
> +	cb_16 = cb - 128;
> +	cr_16 = cr - 128;
> +
> +	r_16 = m[0][0] * y_16 + m[0][1] * cb_16 + m[0][2] * cr_16;
> +	g_16 = m[1][0] * y_16 + m[1][1] * cb_16 + m[1][2] * cr_16;
> +	b_16 = m[2][0] * y_16 + m[2][1] * cb_16 + m[2][2] * cr_16;
> +
> +	*r = clamp(r_16, 0, 0xffff) >> 8;
> +	*g = clamp(g_16, 0, 0xffff) >> 8;
> +	*b = clamp(b_16, 0, 0xffff) >> 8;
> +}
> +
> +static void yuv_u8_to_argb_u16(struct pixel_argb_u16 *argb_u16, const struct pixel_yuv_u8 *yuv_u8,
> +			       enum drm_color_encoding encoding, enum drm_color_range range)
> +{
> +	static const s16 bt601_full[3][3] = {
> +		{256,   0,  359},
> +		{256, -88, -183},
> +		{256, 454,    0},
> +	};
> +	static const s16 bt601[3][3] = {
> +		{298,    0,  409},
> +		{298, -100, -208},
> +		{298,  516,    0},
> +	};
> +	static const s16 rec709_full[3][3] = {
> +		{256,   0,  408},
> +		{256, -48, -120},
> +		{256, 476,   0 },
> +	};
> +	static const s16 rec709[3][3] = {
> +		{298,   0,  459},
> +		{298, -55, -136},
> +		{298, 541,    0},
> +	};
> +	static const s16 bt2020_full[3][3] = {
> +		{256,   0,  377},
> +		{256, -42, -146},
> +		{256, 482,    0},
> +	};
> +	static const s16 bt2020[3][3] = {
> +		{298,   0,  430},
> +		{298, -48, -167},
> +		{298, 548,    0},
> +	};
> +
> +	u8 r = 0;
> +	u8 g = 0;
> +	u8 b = 0;
> +	bool full = range == DRM_COLOR_YCBCR_FULL_RANGE;
> +	unsigned int y_offset = full ? 0 : 16;
> +
> +	switch (encoding) {
> +	case DRM_COLOR_YCBCR_BT601:
> +		ycbcr2rgb(full ? bt601_full : bt601,
> +			  yuv_u8->y, yuv_u8->u, yuv_u8->v, y_offset, &r, &g, &b);
> +		break;
> +	case DRM_COLOR_YCBCR_BT709:
> +		ycbcr2rgb(full ? rec709_full : rec709,
> +			  yuv_u8->y, yuv_u8->u, yuv_u8->v, y_offset, &r, &g, &b);
> +		break;
> +	case DRM_COLOR_YCBCR_BT2020:
> +		ycbcr2rgb(full ? bt2020_full : bt2020,
> +			  yuv_u8->y, yuv_u8->u, yuv_u8->v, y_offset, &r, &g, &b);
> +		break;
> +	default:
> +		pr_warn_once("Not supported color encoding\n");
> +		break;
> +	}
> +
> +	argb_u16->r = r * 257;
> +	argb_u16->g = g * 257;
> +	argb_u16->b = b * 257;
> +}
> +
> +static void semi_planar_yuv_to_argb_u16(u8 **src_pixels, struct pixel_argb_u16 *out_pixel,
> +					enum drm_color_encoding encoding,
> +					enum drm_color_range range)
> +{
> +	struct pixel_yuv_u8 yuv_u8;
> +
> +	yuv_u8.y = src_pixels[0][0];
> +	yuv_u8.u = src_pixels[1][0];
> +	yuv_u8.v = src_pixels[1][1];
> +
> +	yuv_u8_to_argb_u16(out_pixel, &yuv_u8, encoding, range);
> +}
> +
> +static void semi_planar_yvu_to_argb_u16(u8 **src_pixels, struct pixel_argb_u16 *out_pixel,
> +					enum drm_color_encoding encoding,
> +					enum drm_color_range range)
> +{
> +	struct pixel_yuv_u8 yuv_u8;
> +
> +	yuv_u8.y = src_pixels[0][0];
> +	yuv_u8.v = src_pixels[1][0];
> +	yuv_u8.u = src_pixels[1][1];
> +
> +	yuv_u8_to_argb_u16(out_pixel, &yuv_u8, encoding, range);
> +}
> +
> +static void planar_yuv_to_argb_u16(u8 **src_pixels, struct pixel_argb_u16 *out_pixel,
> +				   enum drm_color_encoding encoding, enum drm_color_range range)
> +{
> +	struct pixel_yuv_u8 yuv_u8;
> +
> +	yuv_u8.y = src_pixels[0][0];
> +	yuv_u8.u = src_pixels[1][0];
> +	yuv_u8.v = src_pixels[2][0];
> +
> +	yuv_u8_to_argb_u16(out_pixel, &yuv_u8, encoding, range);
> +}
> +
> +static void planar_yvu_to_argb_u16(u8 **src_pixels, struct pixel_argb_u16 *out_pixel,
> +				   enum drm_color_encoding encoding, enum drm_color_range range)
> +{
> +	struct pixel_yuv_u8 yuv_u8;
> +
> +	yuv_u8.y = src_pixels[0][0];
> +	yuv_u8.v = src_pixels[1][0];
> +	yuv_u8.u = src_pixels[2][0];
> +
> +	yuv_u8_to_argb_u16(out_pixel, &yuv_u8, encoding, range);
> +}
> +
>  /**
>   * vkms_compose_row - compose a single row of a plane
>   * @stage_buffer: output line with the composed pixels
> @@ -267,6 +398,22 @@ void *get_pixel_conversion_function(u32 format)
>  		return &XRGB16161616_to_argb_u16;
>  	case DRM_FORMAT_RGB565:
>  		return &RGB565_to_argb_u16;
> +	case DRM_FORMAT_NV12:
> +	case DRM_FORMAT_NV16:
> +	case DRM_FORMAT_NV24:
> +		return &semi_planar_yuv_to_argb_u16;
> +	case DRM_FORMAT_NV21:
> +	case DRM_FORMAT_NV61:
> +	case DRM_FORMAT_NV42:
> +		return &semi_planar_yvu_to_argb_u16;
> +	case DRM_FORMAT_YUV420:
> +	case DRM_FORMAT_YUV422:
> +	case DRM_FORMAT_YUV444:
> +		return &planar_yuv_to_argb_u16;
> +	case DRM_FORMAT_YVU420:
> +	case DRM_FORMAT_YVU422:
> +	case DRM_FORMAT_YVU444:
> +		return &planar_yvu_to_argb_u16;
>  	default:
>  		return NULL;
>  	}
> diff --git a/drivers/gpu/drm/vkms/vkms_formats.h b/drivers/gpu/drm/vkms/vkms_formats.h
> index cf59c2ed8e9a..a8b2f92bdcb5 100644
> --- a/drivers/gpu/drm/vkms/vkms_formats.h
> +++ b/drivers/gpu/drm/vkms/vkms_formats.h
> @@ -9,4 +9,8 @@ void *get_pixel_conversion_function(u32 format);
>  
>  void *get_pixel_write_function(u32 format);
>  
> +struct pixel_yuv_u8 {
> +	u8 y, u, v;
> +};
> +
>  #endif /* _VKMS_FORMATS_H_ */
> diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
> index e87c80575b7d..932736fc3ee9 100644
> --- a/drivers/gpu/drm/vkms/vkms_plane.c
> +++ b/drivers/gpu/drm/vkms/vkms_plane.c
> @@ -17,7 +17,19 @@ static const u32 vkms_formats[] = {
>  	DRM_FORMAT_XRGB8888,
>  	DRM_FORMAT_XRGB16161616,
>  	DRM_FORMAT_ARGB16161616,
> -	DRM_FORMAT_RGB565
> +	DRM_FORMAT_RGB565,
> +	DRM_FORMAT_NV12,
> +	DRM_FORMAT_NV16,
> +	DRM_FORMAT_NV24,
> +	DRM_FORMAT_NV21,
> +	DRM_FORMAT_NV61,
> +	DRM_FORMAT_NV42,
> +	DRM_FORMAT_YUV420,
> +	DRM_FORMAT_YUV422,
> +	DRM_FORMAT_YUV444,
> +	DRM_FORMAT_YVU420,
> +	DRM_FORMAT_YVU422,
> +	DRM_FORMAT_YVU444
>  };
>  
>  static struct drm_plane_state *
> 
> -- 
> 2.43.0
> 

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>