drm: Add properties to control YCbCr to RGB conversion

Add a standard optional properties to support different non RGB color encodings in DRM planes. COLOR_ENCODING select the supported non RGB color encoding, for instance ITU-R BT.709 YCbCr. COLOR_RANGE selects the value ranges within the selected color encoding. The properties are stored to drm_plane object to allow different set of supported encoding for different planes on the device.

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/gpu/drm/drm_atomic.c     |  8 ++++
 drivers/gpu/drm/drm_color_mgmt.c | 91 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_color_mgmt.h     | 19 +++++++++
 include/drm/drm_plane.h          |  8 ++++
 4 files changed, 126 insertions(+)

drivers/gpu/drm/drm_atomic.c +8 -0

index 77dcef0..8067681 100644
@@ -786,6 +786,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->color_encoding_property) {
+		state->color_encoding = val;
+	} else if (property == plane->color_range_property) {
+		state->color_range = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);

@@ -846,6 +850,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->color_encoding_property) {
+		*val = state->color_encoding;
+	} else if (property == plane->color_range_property) {
+		*val = state->color_range;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {

drivers/gpu/drm/drm_color_mgmt.c +13 -0

index 3eda500..9077bf6 100644
@@ -88,6 +88,19 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * Support for different non RGB color encodings is controlled through
+ * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties:
+ *
+ * "COLOR_ENCODING"
+ * 	Optional plane enum property to support different non RGB
+ * 	color encodings. The driver can provide a subset of standard
+ * 	enum values supported by the DRM plane.
+ *
+ * "COLOR_RANGE"
+ * 	Optional plane enum property to support different non RGB
+ * 	color parameter ranges. The driver can provide a subset of
+ * 	standard enum values supported by the DRM plane.
  */
 
 /**

drivers/gpu/drm/drm_color_mgmt.c +73 -0

+};
+
+static const char * const color_range_name[] = {
+	[DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range",
+	[DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range",
+};
+
+/**
+ * drm_plane_create_color_properties - color encoding related plane properties
+ * @supported_encodings: bitfield indicating supported color encodings
+ * @supported_ranges: bitfileld indicating supported color ranges
+ * @default_encoding: default color encoding
+ * @default_range: default color range
+ *
+ * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE
+ * properties to to the drm_plane object. The supported encodings and
+ * ranges should be provided in supported_encodings and
+ * supported_ranges bitmasks. Each bit set in the bitmask indicates
+ * the its number as enum value being supported.
+ */
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	struct drm_prop_enum_list enum_list[max(DRM_COLOR_ENCODING_MAX,
+						DRM_COLOR_RANGE_MAX)];
+	int i, len;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) {
+		if ((supported_encodings & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_encoding_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_encoding);
+	if (plane->state)
+		plane->state->color_encoding = default_encoding;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) {
+		if ((supported_ranges & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_range_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0,	"COLOR_RANGE",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_range_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_range);
+	if (plane->state)
+		plane->state->color_range = default_range;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_plane_create_color_properties);

include/drm/drm_color_mgmt.h +19 -0

index 03a59cb..b3b6d30 100644
@@ -26,6 +26,7 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 

@@ -37,4 +38,22 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_color_encoding {
+	DRM_COLOR_YCBCR_BT601,
+	DRM_COLOR_YCBCR_BT709,
+	DRM_COLOR_YCBCR_BT2020,
+	DRM_COLOR_ENCODING_MAX,
+};
+
+enum drm_color_range {
+	DRM_COLOR_YCBCR_LIMITED_RANGE,
+	DRM_COLOR_YCBCR_FULL_RANGE,
+	DRM_COLOR_RANGE_MAX,
+};
+
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range);
 #endif

include/drm/drm_plane.h +8 -0

index 9ab3e70..f4de5f9 100644
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;

@@ -112,6 +113,10 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/* Color encoding for non RGB formats */
+	enum drm_color_encoding color_encoding;
+	enum drm_color_range color_range;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 

@@ -523,6 +528,9 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	struct drm_property *color_encoding_property;
+	struct drm_property *color_range_property;
 };
 
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)

Signature · 1 line

1.9.1

Quoted 66 lines · Jyri Sarha

Add a standard optional properties to support different non RGB color encodings in DRM planes. COLOR_ENCODING select the supported non RGB color encoding, for instance ITU-R BT.709 YCbCr. COLOR_RANGE selects the value ranges within the selected color encoding. The properties are stored to drm_plane object to allow different set of supported encoding for different planes on the device.

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/gpu/drm/drm_atomic.c     |  8 ++++
 drivers/gpu/drm/drm_color_mgmt.c | 91 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_color_mgmt.h     | 19 +++++++++
 include/drm/drm_plane.h          |  8 ++++
 4 files changed, 126 insertions(+)

drivers/gpu/drm/drm_atomic.c +8 -0

index 77dcef0..8067681 100644
@@ -786,6 +786,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->color_encoding_property) {
+		state->color_encoding = val;
+	} else if (property == plane->color_range_property) {
+		state->color_range = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);

@@ -846,6 +850,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->color_encoding_property) {
+		*val = state->color_encoding;
+	} else if (property == plane->color_range_property) {
+		*val = state->color_range;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {

drivers/gpu/drm/drm_color_mgmt.c +13 -0

index 3eda500..9077bf6 100644
@@ -88,6 +88,19 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * Support for different non RGB color encodings is controlled through
+ * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties:
+ *
+ * "COLOR_ENCODING"
+ * 	Optional plane enum property to support different non RGB
+ * 	color encodings. The driver can provide a subset of standard
+ * 	enum values supported by the DRM plane.
+ *
+ * "COLOR_RANGE"
+ * 	Optional plane enum property to support different non RGB
+ * 	color parameter ranges. The driver can provide a subset of
+ * 	standard enum values supported by the DRM plane.
  */
 
 /**

drivers/gpu/drm/drm_color_mgmt.c int drm_mode_gamma_get_ioctl(struct drm_device *dev, · line 356

Quoted 8 lines

drivers/gpu/drm/drm_color_mgmt.c +5 -0

@@ -336,3 +349,81 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 	drm_modeset_unlock(&crtc->mutex);
 	return ret;
 }
+
+static const char * const color_encoding_name[] = {
+	[DRM_COLOR_YCBCR_BT601] = "ITU-R BT.601 YCbCr",
+	[DRM_COLOR_YCBCR_BT709] = "ITU-R BT.709 YCbCr",
+	[DRM_COLOR_YCBCR_BT2020] = "ITU-R BT.2020 YCbCr",

I was just looking at this again (in the hopes of landing it finally), and then I realized we probably need to split this BT.2020 into constant and non-constant luminance variants.

..._BT2020_CL and ..._BT2020_NCL maybe?

Quoted 141 lines

drivers/gpu/drm/drm_color_mgmt.c +73 -0

+};
+
+static const char * const color_range_name[] = {
+	[DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range",
+	[DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range",
+};
+
+/**
+ * drm_plane_create_color_properties - color encoding related plane properties
+ * @supported_encodings: bitfield indicating supported color encodings
+ * @supported_ranges: bitfileld indicating supported color ranges
+ * @default_encoding: default color encoding
+ * @default_range: default color range
+ *
+ * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE
+ * properties to to the drm_plane object. The supported encodings and
+ * ranges should be provided in supported_encodings and
+ * supported_ranges bitmasks. Each bit set in the bitmask indicates
+ * the its number as enum value being supported.
+ */
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	struct drm_prop_enum_list enum_list[max(DRM_COLOR_ENCODING_MAX,
+						DRM_COLOR_RANGE_MAX)];
+	int i, len;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) {
+		if ((supported_encodings & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_encoding_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_encoding);
+	if (plane->state)
+		plane->state->color_encoding = default_encoding;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) {
+		if ((supported_ranges & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_range_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0,	"COLOR_RANGE",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_range_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_range);
+	if (plane->state)
+		plane->state->color_range = default_range;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_plane_create_color_properties);

include/drm/drm_color_mgmt.h +19 -0

index 03a59cb..b3b6d30 100644
@@ -26,6 +26,7 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 

@@ -37,4 +38,22 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_color_encoding {
+	DRM_COLOR_YCBCR_BT601,
+	DRM_COLOR_YCBCR_BT709,
+	DRM_COLOR_YCBCR_BT2020,
+	DRM_COLOR_ENCODING_MAX,
+};
+
+enum drm_color_range {
+	DRM_COLOR_YCBCR_LIMITED_RANGE,
+	DRM_COLOR_YCBCR_FULL_RANGE,
+	DRM_COLOR_RANGE_MAX,
+};
+
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range);
 #endif

include/drm/drm_plane.h +8 -0

index 9ab3e70..f4de5f9 100644
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;

@@ -112,6 +113,10 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/* Color encoding for non RGB formats */
+	enum drm_color_encoding color_encoding;
+	enum drm_color_range color_range;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 

@@ -523,6 +528,9 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	struct drm_property *color_encoding_property;
+	struct drm_property *color_range_property;
 };
 

Quoted 3 lines

include/drm/drm_plane.h +0 -0

 #define obj_to_plane(x) container_of(x, struct drm_plane, base)

Signature · 1 line

1.9.1

I have not been following the subject for half a year now. Just let me know if I can do something to help land this patch, e.g. rebase and resend it.

Quoted 263 lines · Ville Syrjälä

Quoted 80 lines · Jyri Sarha

Quoted 66 lines

Add a standard optional properties to support different non RGB color encodings in DRM planes. COLOR_ENCODING select the supported non RGB color encoding, for instance ITU-R BT.709 YCbCr. COLOR_RANGE selects the value ranges within the selected color encoding. The properties are stored to drm_plane object to allow different set of supported encoding for different planes on the device.

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/gpu/drm/drm_atomic.c     |  8 ++++
 drivers/gpu/drm/drm_color_mgmt.c | 91 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_color_mgmt.h     | 19 +++++++++
 include/drm/drm_plane.h          |  8 ++++
 4 files changed, 126 insertions(+)

drivers/gpu/drm/drm_atomic.c +8 -0

index 77dcef0..8067681 100644
@@ -786,6 +786,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->color_encoding_property) {
+		state->color_encoding = val;
+	} else if (property == plane->color_range_property) {
+		state->color_range = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);

@@ -846,6 +850,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->color_encoding_property) {
+		*val = state->color_encoding;
+	} else if (property == plane->color_range_property) {
+		*val = state->color_range;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {

drivers/gpu/drm/drm_color_mgmt.c +13 -0

index 3eda500..9077bf6 100644
@@ -88,6 +88,19 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * Support for different non RGB color encodings is controlled through
+ * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties:
+ *
+ * "COLOR_ENCODING"
+ * 	Optional plane enum property to support different non RGB
+ * 	color encodings. The driver can provide a subset of standard
+ * 	enum values supported by the DRM plane.
+ *
+ * "COLOR_RANGE"
+ * 	Optional plane enum property to support different non RGB
+ * 	color parameter ranges. The driver can provide a subset of
+ * 	standard enum values supported by the DRM plane.
  */
 
 /**

drivers/gpu/drm/drm_color_mgmt.c int drm_mode_gamma_get_ioctl(struct drm_device *dev, · line 356

Quoted 8 lines

drivers/gpu/drm/drm_color_mgmt.c +5 -0

@@ -336,3 +349,81 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 	drm_modeset_unlock(&crtc->mutex);
 	return ret;
 }
+
+static const char * const color_encoding_name[] = {
+	[DRM_COLOR_YCBCR_BT601] = "ITU-R BT.601 YCbCr",
+	[DRM_COLOR_YCBCR_BT709] = "ITU-R BT.709 YCbCr",
+	[DRM_COLOR_YCBCR_BT2020] = "ITU-R BT.2020 YCbCr",

I was just looking at this again (in the hopes of landing it finally), and then I realized we probably need to split this BT.2020 into constant and non-constant luminance variants.

Quoted 1 line

..._BT2020_CL and ..._BT2020_NCL maybe?

This is what V4L2 uses:

https://hverkuil.home.xs4all.nl/spec/uapi/v4l/colorspaces-defs.html

V4L2_YCBCR_ENC_BT2020 and V4L2_YCBCR_ENC_BT2020_CONST_LUM.

I've never seen V4L2_YCBCR_ENC_BT2020_CONST_LUM in the wild. Non-constant Bt.2020 is what is normally used, so I'd keep the define just as-is:
DRM_COLOR_YCBCR_BT2020. And add a DRM_COLOR_YCBCR_BT2020_CONST_LUM if you think you need it. I've never seen anyone use this.

And in case you wonder why: this is the BT.2020 OpenGL Y'CbCr to R'G'B' conversion:

	float r = y + 1.4719 * v;
        float g = y - 0.1646 * u - 0.5703 * v;
        float b = y + 1.8814 * u;

And this for BT.2020 constant luminance:

	float b = u <= 0.0 ? y + 1.9404 * u : y + 1.5816 * u;
	float r = v <= 0.0 ? y + 1.7184 * v : y + 0.9936 * v;
	float lin_r = (r < 0.081) ? r / 4.5 : pow((r + 0.099) / 1.099, 1.0 / 0.45);
	float lin_b = (b < 0.081) ? b / 4.5 : pow((b + 0.099) / 1.099, 1.0 / 0.45);
	float lin_y = (y < 0.081) ? y / 4.5 : pow((y + 0.099) / 1.099, 1.0 / 0.45);
	float lin_g = lin_y / 0.6780 - lin_r * 0.2627 / 0.6780 - lin_b * 0.0593 / 0.6780;
	float g = (lin_g < 0.018) ? lin_g * 4.5 : 1.099 * pow(lin_g, 0.45) - 0.099;

Brr :-)

Regards,

Hans

Quoted 145 lines

Quoted 144 lines

drivers/gpu/drm/drm_color_mgmt.c +73 -0

+};
+
+static const char * const color_range_name[] = {
+	[DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range",
+	[DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range",
+};
+
+/**
+ * drm_plane_create_color_properties - color encoding related plane properties
+ * @supported_encodings: bitfield indicating supported color encodings
+ * @supported_ranges: bitfileld indicating supported color ranges
+ * @default_encoding: default color encoding
+ * @default_range: default color range
+ *
+ * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE
+ * properties to to the drm_plane object. The supported encodings and
+ * ranges should be provided in supported_encodings and
+ * supported_ranges bitmasks. Each bit set in the bitmask indicates
+ * the its number as enum value being supported.
+ */
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	struct drm_prop_enum_list enum_list[max(DRM_COLOR_ENCODING_MAX,
+						DRM_COLOR_RANGE_MAX)];
+	int i, len;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) {
+		if ((supported_encodings & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_encoding_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_encoding);
+	if (plane->state)
+		plane->state->color_encoding = default_encoding;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) {
+		if ((supported_ranges & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_range_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0,	"COLOR_RANGE",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_range_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_range);
+	if (plane->state)
+		plane->state->color_range = default_range;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_plane_create_color_properties);

include/drm/drm_color_mgmt.h +19 -0

index 03a59cb..b3b6d30 100644
@@ -26,6 +26,7 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 

@@ -37,4 +38,22 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_color_encoding {
+	DRM_COLOR_YCBCR_BT601,
+	DRM_COLOR_YCBCR_BT709,
+	DRM_COLOR_YCBCR_BT2020,
+	DRM_COLOR_ENCODING_MAX,
+};
+
+enum drm_color_range {
+	DRM_COLOR_YCBCR_LIMITED_RANGE,
+	DRM_COLOR_YCBCR_FULL_RANGE,
+	DRM_COLOR_RANGE_MAX,
+};
+
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range);
 #endif

include/drm/drm_plane.h +8 -0

index 9ab3e70..f4de5f9 100644
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;

@@ -112,6 +113,10 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/* Color encoding for non RGB formats */
+	enum drm_color_encoding color_encoding;
+	enum drm_color_range color_range;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 

@@ -523,6 +528,9 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	struct drm_property *color_encoding_property;
+	struct drm_property *color_range_property;
 };
 
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)

Signature · 1 line

1.9.1

Signature · 2 lines

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

Quoted 80 lines · Ville Syrjälä

Quoted 66 lines · Jyri Sarha

Add a standard optional properties to support different non RGB color encodings in DRM planes. COLOR_ENCODING select the supported non RGB color encoding, for instance ITU-R BT.709 YCbCr. COLOR_RANGE selects the value ranges within the selected color encoding. The properties are stored to drm_plane object to allow different set of supported encoding for different planes on the device.

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/gpu/drm/drm_atomic.c     |  8 ++++
 drivers/gpu/drm/drm_color_mgmt.c | 91 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_color_mgmt.h     | 19 +++++++++
 include/drm/drm_plane.h          |  8 ++++
 4 files changed, 126 insertions(+)

drivers/gpu/drm/drm_atomic.c +8 -0

index 77dcef0..8067681 100644
@@ -786,6 +786,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->color_encoding_property) {
+		state->color_encoding = val;
+	} else if (property == plane->color_range_property) {
+		state->color_range = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);

@@ -846,6 +850,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->color_encoding_property) {
+		*val = state->color_encoding;
+	} else if (property == plane->color_range_property) {
+		*val = state->color_range;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {

drivers/gpu/drm/drm_color_mgmt.c +13 -0

index 3eda500..9077bf6 100644
@@ -88,6 +88,19 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * Support for different non RGB color encodings is controlled through
+ * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties:
+ *
+ * "COLOR_ENCODING"
+ * 	Optional plane enum property to support different non RGB
+ * 	color encodings. The driver can provide a subset of standard
+ * 	enum values supported by the DRM plane.
+ *
+ * "COLOR_RANGE"
+ * 	Optional plane enum property to support different non RGB
+ * 	color parameter ranges. The driver can provide a subset of
+ * 	standard enum values supported by the DRM plane.
  */
 
 /**

drivers/gpu/drm/drm_color_mgmt.c int drm_mode_gamma_get_ioctl(struct drm_device *dev, · line 356

Quoted 8 lines

drivers/gpu/drm/drm_color_mgmt.c +5 -0

@@ -336,3 +349,81 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 	drm_modeset_unlock(&crtc->mutex);
 	return ret;
 }
+
+static const char * const color_encoding_name[] = {
+	[DRM_COLOR_YCBCR_BT601] = "ITU-R BT.601 YCbCr",
+	[DRM_COLOR_YCBCR_BT709] = "ITU-R BT.709 YCbCr",
+	[DRM_COLOR_YCBCR_BT2020] = "ITU-R BT.2020 YCbCr",

I was just looking at this again (in the hopes of landing it finally), and then I realized we probably need to split this BT.2020 into constant and non-constant luminance variants.

Quoted 1 line

..._BT2020_CL and ..._BT2020_NCL maybe?

This is what V4L2 uses:

https://hverkuil.home.xs4all.nl/spec/uapi/v4l/colorspaces-defs.html

V4L2_YCBCR_ENC_BT2020 and V4L2_YCBCR_ENC_BT2020_CONST_LUM.

I've never seen V4L2_YCBCR_ENC_BT2020_CONST_LUM in the wild. Non-constant Bt.2020 is what is normally used, so I'd keep the define just as-is:
DRM_COLOR_YCBCR_BT2020. And add a DRM_COLOR_YCBCR_BT2020_CONST_LUM if you think you need it. I've never seen anyone use this.

And in case you wonder why: this is the BT.2020 OpenGL Y'CbCr to R'G'B' conversion:

	float r = y + 1.4719 * v;
        float g = y - 0.1646 * u - 0.5703 * v;
        float b = y + 1.8814 * u;

And this for BT.2020 constant luminance:

	float b = u <= 0.0 ? y + 1.9404 * u : y + 1.5816 * u;
	float r = v <= 0.0 ? y + 1.7184 * v : y + 0.9936 * v;
	float lin_r = (r < 0.081) ? r / 4.5 : pow((r + 0.099) / 1.099, 1.0 / 0.45);
	float lin_b = (b < 0.081) ? b / 4.5 : pow((b + 0.099) / 1.099, 1.0 / 0.45);
	float lin_y = (y < 0.081) ? y / 4.5 : pow((y + 0.099) / 1.099, 1.0 / 0.45);
	float lin_g = lin_y / 0.6780 - lin_r * 0.2627 / 0.6780 - lin_b * 0.0593 / 0.6780;
	float g = (lin_g < 0.018) ? lin_g * 4.5 : 1.099 * pow(lin_g, 0.45) - 0.099;

Brr :-)

Regards,

Hans

Quoted 145 lines

Quoted 144 lines

drivers/gpu/drm/drm_color_mgmt.c +73 -0

+};
+
+static const char * const color_range_name[] = {
+	[DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range",
+	[DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range",
+};
+
+/**
+ * drm_plane_create_color_properties - color encoding related plane properties
+ * @supported_encodings: bitfield indicating supported color encodings
+ * @supported_ranges: bitfileld indicating supported color ranges
+ * @default_encoding: default color encoding
+ * @default_range: default color range
+ *
+ * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE
+ * properties to to the drm_plane object. The supported encodings and
+ * ranges should be provided in supported_encodings and
+ * supported_ranges bitmasks. Each bit set in the bitmask indicates
+ * the its number as enum value being supported.
+ */
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	struct drm_prop_enum_list enum_list[max(DRM_COLOR_ENCODING_MAX,
+						DRM_COLOR_RANGE_MAX)];
+	int i, len;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) {
+		if ((supported_encodings & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_encoding_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_encoding);
+	if (plane->state)
+		plane->state->color_encoding = default_encoding;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) {
+		if ((supported_ranges & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_range_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0,	"COLOR_RANGE",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_range_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_range);
+	if (plane->state)
+		plane->state->color_range = default_range;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_plane_create_color_properties);

include/drm/drm_color_mgmt.h +19 -0

index 03a59cb..b3b6d30 100644
@@ -26,6 +26,7 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 

@@ -37,4 +38,22 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_color_encoding {
+	DRM_COLOR_YCBCR_BT601,
+	DRM_COLOR_YCBCR_BT709,
+	DRM_COLOR_YCBCR_BT2020,
+	DRM_COLOR_ENCODING_MAX,
+};
+
+enum drm_color_range {
+	DRM_COLOR_YCBCR_LIMITED_RANGE,
+	DRM_COLOR_YCBCR_FULL_RANGE,
+	DRM_COLOR_RANGE_MAX,
+};
+
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range);
 #endif

include/drm/drm_plane.h +8 -0

index 9ab3e70..f4de5f9 100644
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;

@@ -112,6 +113,10 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/* Color encoding for non RGB formats */
+	enum drm_color_encoding color_encoding;
+	enum drm_color_range color_range;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 

@@ -523,6 +528,9 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	struct drm_property *color_encoding_property;
+	struct drm_property *color_range_property;
 };
 
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)

Signature · 1 line

1.9.1

Quoted 80 lines · Ville Syrjälä

Quoted 66 lines · Jyri Sarha

Add a standard optional properties to support different non RGB color encodings in DRM planes. COLOR_ENCODING select the supported non RGB color encoding, for instance ITU-R BT.709 YCbCr. COLOR_RANGE selects the value ranges within the selected color encoding. The properties are stored to drm_plane object to allow different set of supported encoding for different planes on the device.

Signed-off-by Jyri Sarha <[email protected]>

---
 drivers/gpu/drm/drm_atomic.c     |  8 ++++
 drivers/gpu/drm/drm_color_mgmt.c | 91 ++++++++++++++++++++++++++++++++++++++++
 include/drm/drm_color_mgmt.h     | 19 +++++++++
 include/drm/drm_plane.h          |  8 ++++
 4 files changed, 126 insertions(+)

drivers/gpu/drm/drm_atomic.c +8 -0

index 77dcef0..8067681 100644
@@ -786,6 +786,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->color_encoding_property) {
+		state->color_encoding = val;
+	} else if (property == plane->color_range_property) {
+		state->color_range = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);

@@ -846,6 +850,10 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->color_encoding_property) {
+		*val = state->color_encoding;
+	} else if (property == plane->color_range_property) {
+		*val = state->color_range;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {

drivers/gpu/drm/drm_color_mgmt.c +13 -0

index 3eda500..9077bf6 100644
@@ -88,6 +88,19 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * Support for different non RGB color encodings is controlled through
+ * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties:
+ *
+ * "COLOR_ENCODING"
+ * 	Optional plane enum property to support different non RGB
+ * 	color encodings. The driver can provide a subset of standard
+ * 	enum values supported by the DRM plane.
+ *
+ * "COLOR_RANGE"
+ * 	Optional plane enum property to support different non RGB
+ * 	color parameter ranges. The driver can provide a subset of
+ * 	standard enum values supported by the DRM plane.
  */
 
 /**

drivers/gpu/drm/drm_color_mgmt.c int drm_mode_gamma_get_ioctl(struct drm_device *dev, · line 356

Quoted 8 lines

drivers/gpu/drm/drm_color_mgmt.c +5 -0

@@ -336,3 +349,81 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 	drm_modeset_unlock(&crtc->mutex);
 	return ret;
 }
+
+static const char * const color_encoding_name[] = {
+	[DRM_COLOR_YCBCR_BT601] = "ITU-R BT.601 YCbCr",
+	[DRM_COLOR_YCBCR_BT709] = "ITU-R BT.709 YCbCr",
+	[DRM_COLOR_YCBCR_BT2020] = "ITU-R BT.2020 YCbCr",

I was just looking at this again (in the hopes of landing it finally), and then I realized we probably need to split this BT.2020 into constant and non-constant luminance variants.

Quoted 1 line

..._BT2020_CL and ..._BT2020_NCL maybe?

This is what V4L2 uses:

https://hverkuil.home.xs4all.nl/spec/uapi/v4l/colorspaces-defs.html

V4L2_YCBCR_ENC_BT2020 and V4L2_YCBCR_ENC_BT2020_CONST_LUM.

I've never seen V4L2_YCBCR_ENC_BT2020_CONST_LUM in the wild. Non-constant Bt.2020 is what is normally used, so I'd keep the define just as-is:
DRM_COLOR_YCBCR_BT2020. And add a DRM_COLOR_YCBCR_BT2020_CONST_LUM if you think you need it. I've never seen anyone use this.

And in case you wonder why: this is the BT.2020 OpenGL Y'CbCr to R'G'B' conversion:

	float r = y + 1.4719 * v;
        float g = y - 0.1646 * u - 0.5703 * v;
        float b = y + 1.8814 * u;

And this for BT.2020 constant luminance:

	float b = u <= 0.0 ? y + 1.9404 * u : y + 1.5816 * u;
	float r = v <= 0.0 ? y + 1.7184 * v : y + 0.9936 * v;
	float lin_r = (r < 0.081) ? r / 4.5 : pow((r + 0.099) / 1.099, 1.0 / 0.45);
	float lin_b = (b < 0.081) ? b / 4.5 : pow((b + 0.099) / 1.099, 1.0 / 0.45);
	float lin_y = (y < 0.081) ? y / 4.5 : pow((y + 0.099) / 1.099, 1.0 / 0.45);
	float lin_g = lin_y / 0.6780 - lin_r * 0.2627 / 0.6780 - lin_b * 0.0593 / 0.6780;
	float g = (lin_g < 0.018) ? lin_g * 4.5 : 1.099 * pow(lin_g, 0.45) - 0.099;

Brr :-)

Regards,

Hans

Quoted 145 lines

Quoted 144 lines

drivers/gpu/drm/drm_color_mgmt.c +73 -0

+};
+
+static const char * const color_range_name[] = {
+	[DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range",
+	[DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range",
+};
+
+/**
+ * drm_plane_create_color_properties - color encoding related plane properties
+ * @supported_encodings: bitfield indicating supported color encodings
+ * @supported_ranges: bitfileld indicating supported color ranges
+ * @default_encoding: default color encoding
+ * @default_range: default color range
+ *
+ * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE
+ * properties to to the drm_plane object. The supported encodings and
+ * ranges should be provided in supported_encodings and
+ * supported_ranges bitmasks. Each bit set in the bitmask indicates
+ * the its number as enum value being supported.
+ */
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	struct drm_prop_enum_list enum_list[max(DRM_COLOR_ENCODING_MAX,
+						DRM_COLOR_RANGE_MAX)];
+	int i, len;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) {
+		if ((supported_encodings & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_encoding_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_encoding);
+	if (plane->state)
+		plane->state->color_encoding = default_encoding;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) {
+		if ((supported_ranges & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_range_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0,	"COLOR_RANGE",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_range_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_range);
+	if (plane->state)
+		plane->state->color_range = default_range;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_plane_create_color_properties);

include/drm/drm_color_mgmt.h +19 -0

index 03a59cb..b3b6d30 100644
@@ -26,6 +26,7 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 

@@ -37,4 +38,22 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_color_encoding {
+	DRM_COLOR_YCBCR_BT601,
+	DRM_COLOR_YCBCR_BT709,
+	DRM_COLOR_YCBCR_BT2020,
+	DRM_COLOR_ENCODING_MAX,
+};
+
+enum drm_color_range {
+	DRM_COLOR_YCBCR_LIMITED_RANGE,
+	DRM_COLOR_YCBCR_FULL_RANGE,
+	DRM_COLOR_RANGE_MAX,
+};
+
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range);
 #endif

include/drm/drm_plane.h +8 -0

index 9ab3e70..f4de5f9 100644
@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;

@@ -112,6 +113,10 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/* Color encoding for non RGB formats */
+	enum drm_color_encoding color_encoding;
+	enum drm_color_range color_range;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 

@@ -523,6 +528,9 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	struct drm_property *color_encoding_property;
+	struct drm_property *color_range_property;
 };
 
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)

Signature · 1 line

1.9.1