[PATCH] drm: Add optional COLOR_ENCODING and COLOR_RANGE properties to drm_plane
Ville Syrjälä
ville.syrjala at linux.intel.com
Tue Feb 6 18:45:51 UTC 2018
On Tue, Feb 06, 2018 at 07:08:34PM +0100, Hans Verkuil wrote:
> On 02/06/2018 06:58 PM, Ville Syrjälä wrote:
> > On Mon, Jun 12, 2017 at 12:10:04AM +0300, Jyri Sarha wrote:
> >> 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 <jsarha at ti.com>
> >> ---
> >> 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(+)
> >>
> >> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> >> index 77dcef0..8067681 100644
> >> --- a/drivers/gpu/drm/drm_atomic.c
> >> +++ b/drivers/gpu/drm/drm_atomic.c
> >> @@ -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 {
> >> diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c
> >> index 3eda500..9077bf6 100644
> >> --- a/drivers/gpu/drm/drm_color_mgmt.c
> >> +++ b/drivers/gpu/drm/drm_color_mgmt.c
> >> @@ -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.
> >> */
> >>
> >> /**
> >> @@ -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?
>
> 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.
Hmm. I suppose that's a reasonable apporach. As long as we document that
the the plain BT2020 enum value is in fact the non-const luminance
variant.
>
> 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 :-)
Yeah. In my HDR Weston fork I was doing the non-const luminace with
a generic 4x4 matrix (could be 4x3 but that would have required
some extension I didn't want to look up).
Then I looked at adding the non-const luminance variant, and in
the end decided that I didn't want to uglify the shader code with
that :) If it wasn't for those darned different scaling factors
for the <0.0 vs. >0.0 cases...
>
> Regards,
>
> Hans
>
> >
> >> +};
> >> +
> >> +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);
> >> diff --git a/include/drm/drm_color_mgmt.h b/include/drm/drm_color_mgmt.h
> >> index 03a59cb..b3b6d30 100644
> >> --- a/include/drm/drm_color_mgmt.h
> >> +++ b/include/drm/drm_color_mgmt.h
> >> @@ -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
> >> diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
> >> index 9ab3e70..f4de5f9 100644
> >> --- a/include/drm/drm_plane.h
> >> +++ b/include/drm/drm_plane.h
> >> @@ -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)
> >> --
> >> 1.9.1
> >
--
Ville Syrjälä
Intel OTC
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