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

Arthur Grillo
2024-01-10T17:44:36Z

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