[PATCH v2 6/9] drm/vkms: Add YUV support

From: Louis Chauvet
Date: Fri Feb 23 2024 - 06:39:37 EST


From: Arthur Grillo <arthurgrillo@xxxxxxxxxx>

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@xxxxxxxxxx>
[Louis Chauvet: Adapted Arthur's work and implemented the read_line_t
callbacks for yuv formats]
Signed-off-by: Louis Chauvet <louis.chauvet@xxxxxxxxxxx>
---
drivers/gpu/drm/vkms/vkms_composer.c | 2 +-
drivers/gpu/drm/vkms/vkms_drv.h | 6 +-
drivers/gpu/drm/vkms/vkms_formats.c | 289 +++++++++++++++++++++++++++++++++--
drivers/gpu/drm/vkms/vkms_formats.h | 4 +
drivers/gpu/drm/vkms/vkms_plane.c | 14 +-
5 files changed, 295 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index e555bf9c1aee..54fc5161d565 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -312,7 +312,7 @@ static void blend(struct vkms_writeback_job *wb,
* buffer [1]
*/
current_plane->pixel_read_line(
- current_plane->frame_info,
+ current_plane,
x_start,
y_start,
direction,
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index ccc5be009f15..a4f6456cb971 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -75,6 +75,8 @@ enum pixel_read_direction {
READ_RIGHT
};

+struct vkms_plane_state;
+
/**
<<<<<<< HEAD
* typedef pixel_read_line_t - These functions are used to read a pixel line in the source frame,
@@ -87,8 +89,8 @@ enum pixel_read_direction {
* @out_pixel: Pointer where to write the pixel value. Pixels will be written between x_start and
* x_end.
*/
-typedef void (*pixel_read_line_t)(struct vkms_frame_info *frame_info, int x_start, int y_start, enum
- pixel_read_direction direction, int count, struct pixel_argb_u16 out_pixel[]);
+typedef void (*pixel_read_line_t)(struct vkms_plane_state *frame_info, int x_start, int y_start,
+ enum pixel_read_direction direction, int count, struct pixel_argb_u16 out_pixel[]);

/**
* vkms_plane_state - Driver specific plane state
diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
index 46daea6d3ee9..515c80866a58 100644
--- a/drivers/gpu/drm/vkms/vkms_formats.c
+++ b/drivers/gpu/drm/vkms/vkms_formats.c
@@ -33,7 +33,8 @@ static size_t packed_pixels_offset(const struct vkms_frame_info *frame_info, int
*/
return fb->offsets[plane_index] +
(y / drm_format_info_block_width(format, plane_index)) * fb->pitches[plane_index] +
- (x / drm_format_info_block_height(format, plane_index)) * format->char_per_block[plane_index];
+ (x / drm_format_info_block_height(format, plane_index)) *
+ format->char_per_block[plane_index];
}

/**
@@ -84,6 +85,32 @@ static int get_step_1x1(struct drm_framebuffer *fb, enum pixel_read_direction di
}
}

+/**
+ * get_subsampling() - Get the subsampling value on a specific direction
+ */
+static int get_subsampling(const struct drm_format_info *format,
+ enum pixel_read_direction direction)
+{
+ if (direction == READ_LEFT || direction == READ_RIGHT)
+ return format->hsub;
+ else if (direction == READ_DOWN || direction == READ_UP)
+ return format->vsub;
+ return 1;
+}
+
+/**
+ * get_subsampling_offset() - Get the subsampling offset to use when incrementing the pixel counter
+ */
+static int get_subsampling_offset(const struct drm_format_info *format,
+ enum pixel_read_direction direction, int x_start, int y_start)
+{
+ if (direction == READ_RIGHT || direction == READ_LEFT)
+ return x_start;
+ else if (direction == READ_DOWN || direction == READ_UP)
+ return y_start;
+ return 0;
+}
+

/*
* The following functions take pixel data (a, r, g, b, pixel, ...), convert them to the format
@@ -130,6 +157,87 @@ static void RGB565_to_argb_u16(struct pixel_argb_u16 *out_pixel, const u16 *pixe
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;
+}
+
/*
* The following functions are read_line function for each pixel format supported by VKMS.
*
@@ -142,13 +250,13 @@ static void RGB565_to_argb_u16(struct pixel_argb_u16 *out_pixel, const u16 *pixe
* [1]: https://lore.kernel.org/dri-devel/d258c8dc-78e9-4509-9037-a98f7f33b3a3@xxxxxxxxxx/
*/

-static void ARGB8888_read_line(struct vkms_frame_info *frame_info, int x_start, int y_start,
+static void ARGB8888_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
enum pixel_read_direction direction, int count,
struct pixel_argb_u16 out_pixel[])
{
- u8 *src_pixels = packed_pixels_addr(frame_info, x_start, y_start, 0);
+ u8 *src_pixels = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);

- int step = get_step_1x1(frame_info->fb, direction, 0);
+ int step = get_step_1x1(plane->frame_info->fb, direction, 0);

while (count) {
u8 *px = (u8 *)src_pixels;
@@ -160,13 +268,13 @@ static void ARGB8888_read_line(struct vkms_frame_info *frame_info, int x_start,
}
}

-static void XRGB8888_read_line(struct vkms_frame_info *frame_info, int x_start, int y_start,
+static void XRGB8888_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
enum pixel_read_direction direction, int count,
struct pixel_argb_u16 out_pixel[])
{
- u8 *src_pixels = packed_pixels_addr(frame_info, x_start, y_start, 0);
+ u8 *src_pixels = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);

- int step = get_step_1x1(frame_info->fb, direction, 0);
+ int step = get_step_1x1(plane->frame_info->fb, direction, 0);

while (count) {
u8 *px = (u8 *)src_pixels;
@@ -178,13 +286,13 @@ static void XRGB8888_read_line(struct vkms_frame_info *frame_info, int x_start,
}
}

-static void ARGB16161616_read_line(struct vkms_frame_info *frame_info, int x_start, int y_start,
+static void ARGB16161616_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
enum pixel_read_direction direction, int count,
struct pixel_argb_u16 out_pixel[])
{
- u8 *src_pixels = packed_pixels_addr(frame_info, x_start, y_start, 0);
+ u8 *src_pixels = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);

- int step = get_step_1x1(frame_info->fb, direction, 0);
+ int step = get_step_1x1(plane->frame_info->fb, direction, 0);

while (count) {
u16 *px = (u16 *)src_pixels;
@@ -196,13 +304,13 @@ static void ARGB16161616_read_line(struct vkms_frame_info *frame_info, int x_sta
}
}

-static void XRGB16161616_read_line(struct vkms_frame_info *frame_info, int x_start, int y_start,
+static void XRGB16161616_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
enum pixel_read_direction direction, int count,
struct pixel_argb_u16 out_pixel[])
{
- u8 *src_pixels = packed_pixels_addr(frame_info, x_start, y_start, 0);
+ u8 *src_pixels = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);

- int step = get_step_1x1(frame_info->fb, direction, 0);
+ int step = get_step_1x1(plane->frame_info->fb, direction, 0);

while (count) {
u16 *px = (u16 *)src_pixels;
@@ -214,13 +322,13 @@ static void XRGB16161616_read_line(struct vkms_frame_info *frame_info, int x_sta
}
}

-static void RGB565_read_line(struct vkms_frame_info *frame_info, int x_start, int y_start,
+static void RGB565_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
enum pixel_read_direction direction, int count,
struct pixel_argb_u16 out_pixel[])
{
- u8 *src_pixels = packed_pixels_addr(frame_info, x_start, y_start, 0);
+ u8 *src_pixels = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);

- int step = get_step_1x1(frame_info->fb, direction, 0);
+ int step = get_step_1x1(plane->frame_info->fb, direction, 0);

while (count) {
u16 *px = (u16 *)src_pixels;
@@ -232,6 +340,139 @@ static void RGB565_read_line(struct vkms_frame_info *frame_info, int x_start, in
}
}

+static void semi_planar_yuv_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
+ enum pixel_read_direction direction, int count,
+ struct pixel_argb_u16 out_pixel[])
+{
+ u8 *y_plane = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);
+ u8 *uv_plane = packed_pixels_addr(plane->frame_info,
+ x_start / plane->frame_info->fb->format->hsub,
+ y_start / plane->frame_info->fb->format->vsub,
+ 1);
+ struct pixel_yuv_u8 yuv_u8;
+ int step_y = get_step_1x1(plane->frame_info->fb, direction, 0);
+ int step_uv = get_step_1x1(plane->frame_info->fb, direction, 1);
+ int subsampling = get_subsampling(plane->frame_info->fb->format, direction);
+ int subsampling_offset = get_subsampling_offset(plane->frame_info->fb->format, direction,
+ x_start, y_start); // 0
+
+ for (int i = 0; i < count; i++) {
+ yuv_u8.y = y_plane[0];
+ yuv_u8.u = uv_plane[0];
+ yuv_u8.v = uv_plane[1];
+
+ yuv_u8_to_argb_u16(out_pixel, &yuv_u8, plane->base.base.color_encoding,
+ plane->base.base.color_range);
+ out_pixel += 1;
+ y_plane += step_y;
+ if ((i + subsampling_offset + 1) % subsampling == 0)
+ uv_plane += step_uv;
+ }
+}
+
+static void semi_planar_yvu_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
+ enum pixel_read_direction direction, int count,
+ struct pixel_argb_u16 out_pixel[])
+{
+ u8 *y_plane = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);
+ u8 *vu_plane = packed_pixels_addr(plane->frame_info,
+ x_start / plane->frame_info->fb->format->hsub,
+ y_start / plane->frame_info->fb->format->vsub,
+ 1);
+ struct pixel_yuv_u8 yuv_u8;
+ int step_y = get_step_1x1(plane->frame_info->fb, direction, 0);
+ int step_vu = get_step_1x1(plane->frame_info->fb, direction, 1);
+ int subsampling = get_subsampling(plane->frame_info->fb->format, direction);
+ int subsampling_offset = get_subsampling_offset(plane->frame_info->fb->format, direction,
+ x_start, y_start);
+ for (int i = 0; i < count; i++) {
+ yuv_u8.y = y_plane[0];
+ yuv_u8.u = vu_plane[1];
+ yuv_u8.v = vu_plane[0];
+
+ yuv_u8_to_argb_u16(out_pixel, &yuv_u8, plane->base.base.color_encoding,
+ plane->base.base.color_range);
+ out_pixel += 1;
+ y_plane += step_y;
+ if ((i + subsampling_offset + 1) % subsampling == 0)
+ vu_plane += step_vu;
+ }
+}
+
+static void planar_yuv_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
+ enum pixel_read_direction direction, int count,
+ struct pixel_argb_u16 out_pixel[])
+{
+ u8 *y_plane = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);
+ u8 *u_plane = packed_pixels_addr(plane->frame_info,
+ x_start / plane->frame_info->fb->format->hsub,
+ y_start / plane->frame_info->fb->format->vsub,
+ 1);
+ u8 *v_plane = packed_pixels_addr(plane->frame_info,
+ x_start / plane->frame_info->fb->format->hsub,
+ y_start / plane->frame_info->fb->format->vsub,
+ 2);
+ struct pixel_yuv_u8 yuv_u8;
+ int step_y = get_step_1x1(plane->frame_info->fb, direction, 0);
+ int step_u = get_step_1x1(plane->frame_info->fb, direction, 1);
+ int step_v = get_step_1x1(plane->frame_info->fb, direction, 2);
+ int subsampling = get_subsampling(plane->frame_info->fb->format, direction);
+ int subsampling_offset = get_subsampling_offset(plane->frame_info->fb->format, direction,
+ x_start, y_start);
+
+ for (int i = 0; i < count; i++) {
+ yuv_u8.y = *y_plane;
+ yuv_u8.u = *u_plane;
+ yuv_u8.v = *v_plane;
+
+ yuv_u8_to_argb_u16(out_pixel, &yuv_u8, plane->base.base.color_encoding,
+ plane->base.base.color_range);
+ out_pixel += 1;
+ y_plane += step_y;
+ if ((i + subsampling_offset + 1) % subsampling == 0) {
+ u_plane += step_u;
+ v_plane += step_v;
+ }
+ }
+}
+
+static void planar_yvu_read_line(struct vkms_plane_state *plane, int x_start, int y_start,
+ enum pixel_read_direction direction, int count,
+ struct pixel_argb_u16 out_pixel[])
+{
+ u8 *y_plane = packed_pixels_addr(plane->frame_info, x_start, y_start, 0);
+ u8 *v_plane = packed_pixels_addr(plane->frame_info,
+ x_start / plane->frame_info->fb->format->hsub,
+ y_start / plane->frame_info->fb->format->vsub,
+ 1);
+ u8 *u_plane = packed_pixels_addr(plane->frame_info,
+ x_start / plane->frame_info->fb->format->hsub,
+ y_start / plane->frame_info->fb->format->vsub,
+ 2);
+ struct pixel_yuv_u8 yuv_u8;
+ int step_y = get_step_1x1(plane->frame_info->fb, direction, 0);
+ int step_u = get_step_1x1(plane->frame_info->fb, direction, 1);
+ int step_v = get_step_1x1(plane->frame_info->fb, direction, 2);
+ int subsampling = get_subsampling(plane->frame_info->fb->format, direction);
+ int subsampling_offset = get_subsampling_offset(plane->frame_info->fb->format, direction,
+ x_start, y_start);
+
+ for (int i = 0; i < count; i++) {
+ yuv_u8.y = *y_plane;
+ yuv_u8.u = *u_plane;
+ yuv_u8.v = *v_plane;
+
+ yuv_u8_to_argb_u16(out_pixel, &yuv_u8, plane->base.base.color_encoding,
+ plane->base.base.color_range);
+ out_pixel += 1;
+ y_plane += step_y;
+ if ((i + subsampling_offset + 1) % subsampling == 0) {
+ u_plane += step_u;
+ v_plane += step_v;
+ }
+ }
+}
+
/*
* The following functions take one argb_u16 pixel and convert it to a specific format. The
* result is stored in @dst_pixels.
@@ -344,6 +585,22 @@ pixel_read_line_t get_pixel_read_line_function(u32 format)
return &XRGB16161616_read_line;
case DRM_FORMAT_RGB565:
return &RGB565_read_line;
+ case DRM_FORMAT_NV12:
+ case DRM_FORMAT_NV16:
+ case DRM_FORMAT_NV24:
+ return &semi_planar_yuv_read_line;
+ case DRM_FORMAT_NV21:
+ case DRM_FORMAT_NV61:
+ case DRM_FORMAT_NV42:
+ return &semi_planar_yvu_read_line;
+ case DRM_FORMAT_YUV420:
+ case DRM_FORMAT_YUV422:
+ case DRM_FORMAT_YUV444:
+ return &planar_yuv_read_line;
+ case DRM_FORMAT_YVU420:
+ case DRM_FORMAT_YVU422:
+ case DRM_FORMAT_YVU444:
+ return &planar_yvu_read_line;
default:
return (pixel_read_line_t)NULL;
}
diff --git a/drivers/gpu/drm/vkms/vkms_formats.h b/drivers/gpu/drm/vkms/vkms_formats.h
index 8d2bef95ff79..5a3a9e1328d8 100644
--- a/drivers/gpu/drm/vkms/vkms_formats.h
+++ b/drivers/gpu/drm/vkms/vkms_formats.h
@@ -9,4 +9,8 @@ pixel_read_line_t get_pixel_read_line_function(u32 format);

pixel_write_t 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 58c1c74742b5..427ca67c60ce 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