diff mbox series

[v10,1/3] drm: Add HDMI colorspace property

Message ID 1548852866-32349-2-git-send-email-uma.shankar@intel.com (mailing list archive)
State New, archived
Headers show
Series Add Colorspace connector property interface | expand

Commit Message

Shankar, Uma Jan. 30, 2019, 12:54 p.m. UTC
Create a new connector property to program colorspace to sink
devices. Modern sink devices support more than 1 type of
colorspace like 601, 709, BT2020 etc. This helps to switch
based on content type which is to be displayed. The decision
lies with compositors as to in which scenarios, a particular
colorspace will be picked.

This will be helpful mostly to switch to higher gamut colorspaces
like BT2020 when the media content is encoded as BT2020. Thereby
giving a good visual experience to users.

The expectation from userspace is that it should parse the EDID
and get supported colorspaces. Use this property and switch to the
one supported. Sink supported colorspaces should be retrieved by
userspace from EDID and driver will not explicitly expose them.

Basically the expectation from userspace is:
 - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
   colorspace
 - Set this new property to let the sink know what it
   converted the CRTC output to.

v2: Addressed Maarten and Ville's review comments. Enhanced
the colorspace enum to incorporate both HDMI and DP supported
colorspaces. Also, added a default option for colorspace.

v3: Removed Adobe references from enum definitions as per
Ville, Hans Verkuil and Jonas Karlman suggestions. Changed
Default to an unset state where driver will assign the colorspace
is not chosen by user, suggested by Ville and Maarten. Addressed
other misc review comments from Maarten. Split the changes to
have separate colorspace property for DP and HDMI.

v4: Addressed Chris and Ville's review comments, and created a
common colorspace property for DP and HDMI, filtered the list
based on the colorspaces supported by the respective protocol
standard.

v5: Made the property creation helper accept enum list based on
platform capabilties as suggested by Shashank. Consolidated HDMI
and DP property creation in the common helper.

v6: Addressed Shashank's review comments.

v7: Added defines instead of enum in uapi as per Brian Starkey's
suggestion in order to go with string matching at userspace. Updated
the commit message to add more details as well kernel docs.

v8: Addressed Maarten's review comments.

v9: Removed macro defines from uapi as per Brian Starkey and Daniel
Stone's comments and moved to drm include file. Moved back to older
design with exposing all HDMI colorspaces to userspace since infoframe
capability is there even on legacy platforms, as per Ville's review
comments.

v10: Fixed sparse warnings, updated the RB from Maarten and Jani's ack.

Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
 drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
 drivers/gpu/drm/drm_connector.c   | 75 +++++++++++++++++++++++++++++++++++++++
 include/drm/drm_connector.h       | 46 ++++++++++++++++++++++++
 3 files changed, 125 insertions(+)

Comments

Ville Syrjala Feb. 1, 2019, 6:50 p.m. UTC | #1
On Wed, Jan 30, 2019 at 06:24:24PM +0530, Uma Shankar wrote:
> Create a new connector property to program colorspace to sink
> devices. Modern sink devices support more than 1 type of
> colorspace like 601, 709, BT2020 etc. This helps to switch
> based on content type which is to be displayed. The decision
> lies with compositors as to in which scenarios, a particular
> colorspace will be picked.
> 
> This will be helpful mostly to switch to higher gamut colorspaces
> like BT2020 when the media content is encoded as BT2020. Thereby
> giving a good visual experience to users.
> 
> The expectation from userspace is that it should parse the EDID
> and get supported colorspaces. Use this property and switch to the
> one supported. Sink supported colorspaces should be retrieved by
> userspace from EDID and driver will not explicitly expose them.
> 
> Basically the expectation from userspace is:
>  - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
>    colorspace
>  - Set this new property to let the sink know what it
>    converted the CRTC output to.
> 
> v2: Addressed Maarten and Ville's review comments. Enhanced
> the colorspace enum to incorporate both HDMI and DP supported
> colorspaces. Also, added a default option for colorspace.
> 
> v3: Removed Adobe references from enum definitions as per
> Ville, Hans Verkuil and Jonas Karlman suggestions. Changed
> Default to an unset state where driver will assign the colorspace
> is not chosen by user, suggested by Ville and Maarten. Addressed
> other misc review comments from Maarten. Split the changes to
> have separate colorspace property for DP and HDMI.
> 
> v4: Addressed Chris and Ville's review comments, and created a
> common colorspace property for DP and HDMI, filtered the list
> based on the colorspaces supported by the respective protocol
> standard.
> 
> v5: Made the property creation helper accept enum list based on
> platform capabilties as suggested by Shashank. Consolidated HDMI
> and DP property creation in the common helper.
> 
> v6: Addressed Shashank's review comments.
> 
> v7: Added defines instead of enum in uapi as per Brian Starkey's
> suggestion in order to go with string matching at userspace. Updated
> the commit message to add more details as well kernel docs.
> 
> v8: Addressed Maarten's review comments.
> 
> v9: Removed macro defines from uapi as per Brian Starkey and Daniel
> Stone's comments and moved to drm include file. Moved back to older
> design with exposing all HDMI colorspaces to userspace since infoframe
> capability is there even on legacy platforms, as per Ville's review
> comments.
> 
> v10: Fixed sparse warnings, updated the RB from Maarten and Jani's ack.
> 
> Signed-off-by: Uma Shankar <uma.shankar@intel.com>
> Acked-by: Jani Nikula <jani.nikula@intel.com>
> Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> ---
>  drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
>  drivers/gpu/drm/drm_connector.c   | 75 +++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_connector.h       | 46 ++++++++++++++++++++++++
>  3 files changed, 125 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> index 9a1f41a..9b5d44f 100644
> --- a/drivers/gpu/drm/drm_atomic_uapi.c
> +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> @@ -746,6 +746,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
>  			return -EINVAL;
>  		}
>  		state->content_protection = val;
> +	} else if (property == connector->colorspace_property) {
> +		state->colorspace = val;
>  	} else if (property == config->writeback_fb_id_property) {
>  		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, NULL, val);
>  		int ret = drm_atomic_set_writeback_fb_for_connector(state, fb);
> @@ -814,6 +816,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
>  		*val = state->picture_aspect_ratio;
>  	} else if (property == config->content_type_property) {
>  		*val = state->content_type;
> +	} else if (property == connector->colorspace_property) {
> +		*val = state->colorspace;
>  	} else if (property == connector->scaling_mode_property) {
>  		*val = state->scaling_mode;
>  	} else if (property == connector->content_protection_property) {
> diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> index 8475396..ed10dd9 100644
> --- a/drivers/gpu/drm/drm_connector.c
> +++ b/drivers/gpu/drm/drm_connector.c
> @@ -826,6 +826,30 @@ int drm_display_info_set_bus_formats(struct drm_display_info *info,
>  };
>  DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
>  
> +static const struct drm_prop_enum_list hdmi_colorspaces[] = {
> +	/* For Default case, driver will set the colorspace */
> +	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
> +	/* Standard Definition Colorimetry based on CEA 861 */
> +	{ DRM_MODE_COLORIMETRY_ITU_601, "ITU_601" },

The spec no longer has the BT.601 note here. Which I guess makes sense
since BT.601 didn't even specify any color primaries initially. Later
versions do by they have distinct primaries for NTSC vs. PAL. The spec
calls this just SMPTE 170M now, so I think we should do the same.

> +	{ DRM_MODE_COLORIMETRY_ITU_709, "ITU_709" },
> +	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
> +	{ DRM_MODE_COLORIMETRY_XV_YCC_601, "XV_YCC_601" },
> +	/* High Definition Colorimetry based on IEC 61966-2-4 */
> +	{ DRM_MODE_COLORIMETRY_XV_YCC_709, "XV_YCC_709" },
> +	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
> +	{ DRM_MODE_COLORIMETRY_S_YCC_601, "S_YCC_601" },
> +	/* Colorimetry based on IEC 61966-2-5 [33] */
> +	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },

The spelling is rather inconsistent here. XV_ vs. S_ vs. op. Why not use
the same spelling style for all?

> +	/* Colorimetry based on IEC 61966-2-5 */
> +	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
> +	/* Colorimetry based on ITU-R BT.2020 */
> +	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
> +	/* Colorimetry based on ITU-R BT.2020 */
> +	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
> +	/* Colorimetry based on ITU-R BT.2020 */
> +	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },

"BT2020" vs. "ITU_709" is rather inconsistent as well.

We also seem to be missing the two DCI-P3 things here.

> +};
> +
>  /**
>   * DOC: standard connector properties
>   *
> @@ -1548,6 +1572,57 @@ int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
>  EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
>  
>  /**
> + * DOC: standard connector properties
> + *
> + * Colorspace:
> + *     drm_mode_create_colorspace_property - create colorspace property
> + *     This property helps select a suitable colorspace based on the sink
> + *     capability. Modern sink devices support wider gamut like BT2020.
> + *     This helps switch to BT2020 mode if the BT2020 encoded video stream
> + *     is being played by the user, same for any other colorspace. Thereby
> + *     giving a good visual experience to users.
> + *
> + *     The expectation from userspace is that it should parse the EDID
> + *     and get supported colorspaces. Use this property and switch to the
> + *     one supported. Sink supported colorspaces should be retrieved by
> + *     userspace from EDID and driver will not explicitly expose them.
> + *
> + *     Basically the expectation from userspace is:
> + *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
> + *        colorspace
> + *      - Set this new property to let the sink know what it
> + *        converted the CRTC output to.
> + *      - This property is just to inform sink what colorspace
> + *        source is trying to drive.
> + *
> + * Called by a driver the first time it's needed, must be attached to desired
> + * connectors.
> + */
> +int drm_mode_create_colorspace_property(struct drm_connector *connector)
> +{
> +	struct drm_device *dev = connector->dev;
> +	struct drm_property *prop;
> +
> +	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
> +	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
> +		prop = drm_property_create_enum(dev, DRM_MODE_PROP_ENUM,
> +						"Colorspace",
> +						hdmi_colorspaces,
> +						ARRAY_SIZE(hdmi_colorspaces));
> +		if (!prop)
> +			return -ENOMEM;
> +	} else {
> +		DRM_DEBUG_KMS("Colorspace property not supported\n");
> +		return 0;
> +	}
> +
> +	connector->colorspace_property = prop;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(drm_mode_create_colorspace_property);
> +
> +/**
>   * drm_mode_create_content_type_property - create content type property
>   * @dev: DRM device
>   *
> diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> index 9941613..29495b3 100644
> --- a/include/drm/drm_connector.h
> +++ b/include/drm/drm_connector.h
> @@ -253,6 +253,38 @@ enum drm_panel_orientation {
>  	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
>  };
>  
> +/*
> + * This is a consolidated colorimetry list supported by HDMI and
> + * DP protocol standard. The respective connectors will register
> + * a property with the subset of this list (supported by that
> + * respective protocol). Userspace will set the colorspace through
> + * a colorspace property which will be created and exposed to
> + * userspace.
> + */
> +
> +/* For Default case, driver will set the colorspace */
> +#define DRM_MODE_COLORIMETRY_DEFAULT			0
> +/* CEA 861 Normal Colorimetry options */
> +#define DRM_MODE_COLORIMETRY_ITU_601			1
> +#define DRM_MODE_COLORIMETRY_ITU_709			2
> +/* CEA 861 Extended Colorimetry Options */
> +#define DRM_MODE_COLORIMETRY_XV_YCC_601			3
> +#define DRM_MODE_COLORIMETRY_XV_YCC_709			4
> +#define DRM_MODE_COLORIMETRY_S_YCC_601			5
> +#define DRM_MODE_COLORIMETRY_OPYCC_601			6
> +#define DRM_MODE_COLORIMETRY_OPRGB			7
> +#define DRM_MODE_COLORIMETRY_BT2020_RGB			8
> +#define DRM_MODE_COLORIMETRY_BT2020_YCC			9
> +#define DRM_MODE_COLORIMETRY_BT2020_CYCC		10
> +/* DP MSA Colorimetry Options */
> +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_601		11
> +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_709		12
> +#define DRM_MODE_DP_COLORIMETRY_SRGB			13
> +#define DRM_MODE_DP_COLORIMETRY_RGB_WIDE_GAMUT		14
> +#define DRM_MODE_DP_COLORIMETRY_SCRGB			15
> +#define DRM_MODE_DP_COLORIMETRY_DCI_P3			16
> +#define DRM_MODE_DP_COLORIMETRY_CUSTOM_COLOR_PROFILE	17

I think some kind of macro to define these would be good. Assuming we're
trying directly interpret these as the C/EC/ACE bits. I can't remember
if multiple enum values can have the same integer value. If not we'd
also need a YCbCr vs. RGB bit in there somewhere. Assuming we want to
keep RGB and YCbCr separate. Currently only BT.2020 has a conflict
between the two.

> +
>  /**
>   * struct drm_display_info - runtime data about the connected sink
>   *
> @@ -503,6 +535,13 @@ struct drm_connector_state {
>  	unsigned int content_protection;
>  
>  	/**
> +	 * @colorspace: State variable for Connector property to request
> +	 * colorspace change on Sink. This is most commonly used to switch
> +	 * to wider color gamuts like BT2020.
> +	 */
> +	u32 colorspace;
> +
> +	/**
>  	 * @writeback_job: Writeback job for writeback connectors
>  	 *
>  	 * Holds the framebuffer and out-fence for a writeback connector. As
> @@ -995,6 +1034,12 @@ struct drm_connector {
>  	struct drm_property *content_protection_property;
>  
>  	/**
> +	 * @colorspace_property: Connector property to set the suitable
> +	 * colorspace supported by the sink.
> +	 */
> +	struct drm_property *colorspace_property;
> +
> +	/**
>  	 * @path_blob_ptr:
>  	 *
>  	 * DRM blob property data for the DP MST path property. This should only
> @@ -1269,6 +1314,7 @@ int drm_connector_attach_vrr_capable_property(
>  int drm_connector_attach_content_protection_property(
>  		struct drm_connector *connector);
>  int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
> +int drm_mode_create_colorspace_property(struct drm_connector *connector);
>  int drm_mode_create_content_type_property(struct drm_device *dev);
>  void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame,
>  					 const struct drm_connector_state *conn_state);
> -- 
> 1.9.1
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Ville Syrjala Feb. 4, 2019, 3:25 p.m. UTC | #2
On Fri, Feb 01, 2019 at 08:50:11PM +0200, Ville Syrjälä wrote:
> On Wed, Jan 30, 2019 at 06:24:24PM +0530, Uma Shankar wrote:
> > Create a new connector property to program colorspace to sink
> > devices. Modern sink devices support more than 1 type of
> > colorspace like 601, 709, BT2020 etc. This helps to switch
> > based on content type which is to be displayed. The decision
> > lies with compositors as to in which scenarios, a particular
> > colorspace will be picked.
> > 
> > This will be helpful mostly to switch to higher gamut colorspaces
> > like BT2020 when the media content is encoded as BT2020. Thereby
> > giving a good visual experience to users.
> > 
> > The expectation from userspace is that it should parse the EDID
> > and get supported colorspaces. Use this property and switch to the
> > one supported. Sink supported colorspaces should be retrieved by
> > userspace from EDID and driver will not explicitly expose them.
> > 
> > Basically the expectation from userspace is:
> >  - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
> >    colorspace
> >  - Set this new property to let the sink know what it
> >    converted the CRTC output to.
> > 
> > v2: Addressed Maarten and Ville's review comments. Enhanced
> > the colorspace enum to incorporate both HDMI and DP supported
> > colorspaces. Also, added a default option for colorspace.
> > 
> > v3: Removed Adobe references from enum definitions as per
> > Ville, Hans Verkuil and Jonas Karlman suggestions. Changed
> > Default to an unset state where driver will assign the colorspace
> > is not chosen by user, suggested by Ville and Maarten. Addressed
> > other misc review comments from Maarten. Split the changes to
> > have separate colorspace property for DP and HDMI.
> > 
> > v4: Addressed Chris and Ville's review comments, and created a
> > common colorspace property for DP and HDMI, filtered the list
> > based on the colorspaces supported by the respective protocol
> > standard.
> > 
> > v5: Made the property creation helper accept enum list based on
> > platform capabilties as suggested by Shashank. Consolidated HDMI
> > and DP property creation in the common helper.
> > 
> > v6: Addressed Shashank's review comments.
> > 
> > v7: Added defines instead of enum in uapi as per Brian Starkey's
> > suggestion in order to go with string matching at userspace. Updated
> > the commit message to add more details as well kernel docs.
> > 
> > v8: Addressed Maarten's review comments.
> > 
> > v9: Removed macro defines from uapi as per Brian Starkey and Daniel
> > Stone's comments and moved to drm include file. Moved back to older
> > design with exposing all HDMI colorspaces to userspace since infoframe
> > capability is there even on legacy platforms, as per Ville's review
> > comments.
> > 
> > v10: Fixed sparse warnings, updated the RB from Maarten and Jani's ack.
> > 
> > Signed-off-by: Uma Shankar <uma.shankar@intel.com>
> > Acked-by: Jani Nikula <jani.nikula@intel.com>
> > Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
> > Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> > ---
> >  drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
> >  drivers/gpu/drm/drm_connector.c   | 75 +++++++++++++++++++++++++++++++++++++++
> >  include/drm/drm_connector.h       | 46 ++++++++++++++++++++++++
> >  3 files changed, 125 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
> > index 9a1f41a..9b5d44f 100644
> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> > @@ -746,6 +746,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
> >  			return -EINVAL;
> >  		}
> >  		state->content_protection = val;
> > +	} else if (property == connector->colorspace_property) {
> > +		state->colorspace = val;
> >  	} else if (property == config->writeback_fb_id_property) {
> >  		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, NULL, val);
> >  		int ret = drm_atomic_set_writeback_fb_for_connector(state, fb);
> > @@ -814,6 +816,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
> >  		*val = state->picture_aspect_ratio;
> >  	} else if (property == config->content_type_property) {
> >  		*val = state->content_type;
> > +	} else if (property == connector->colorspace_property) {
> > +		*val = state->colorspace;
> >  	} else if (property == connector->scaling_mode_property) {
> >  		*val = state->scaling_mode;
> >  	} else if (property == connector->content_protection_property) {
> > diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
> > index 8475396..ed10dd9 100644
> > --- a/drivers/gpu/drm/drm_connector.c
> > +++ b/drivers/gpu/drm/drm_connector.c
> > @@ -826,6 +826,30 @@ int drm_display_info_set_bus_formats(struct drm_display_info *info,
> >  };
> >  DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
> >  
> > +static const struct drm_prop_enum_list hdmi_colorspaces[] = {
> > +	/* For Default case, driver will set the colorspace */
> > +	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
> > +	/* Standard Definition Colorimetry based on CEA 861 */
> > +	{ DRM_MODE_COLORIMETRY_ITU_601, "ITU_601" },
> 
> The spec no longer has the BT.601 note here. Which I guess makes sense
> since BT.601 didn't even specify any color primaries initially. Later
> versions do by they have distinct primaries for NTSC vs. PAL. The spec
> calls this just SMPTE 170M now, so I think we should do the same.
> 
> > +	{ DRM_MODE_COLORIMETRY_ITU_709, "ITU_709" },
> > +	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_601, "XV_YCC_601" },
> > +	/* High Definition Colorimetry based on IEC 61966-2-4 */
> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_709, "XV_YCC_709" },
> > +	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
> > +	{ DRM_MODE_COLORIMETRY_S_YCC_601, "S_YCC_601" },
> > +	/* Colorimetry based on IEC 61966-2-5 [33] */
> > +	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
> 
> The spelling is rather inconsistent here. XV_ vs. S_ vs. op. Why not use
> the same spelling style for all?
> 
> > +	/* Colorimetry based on IEC 61966-2-5 */
> > +	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
> > +	/* Colorimetry based on ITU-R BT.2020 */
> > +	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
> > +	/* Colorimetry based on ITU-R BT.2020 */
> > +	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
> > +	/* Colorimetry based on ITU-R BT.2020 */
> > +	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
> 
> "BT2020" vs. "ITU_709" is rather inconsistent as well.
> 
> We also seem to be missing the two DCI-P3 things here.
> 
> > +};
> > +
> >  /**
> >   * DOC: standard connector properties
> >   *
> > @@ -1548,6 +1572,57 @@ int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
> >  EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
> >  
> >  /**
> > + * DOC: standard connector properties
> > + *
> > + * Colorspace:
> > + *     drm_mode_create_colorspace_property - create colorspace property
> > + *     This property helps select a suitable colorspace based on the sink
> > + *     capability. Modern sink devices support wider gamut like BT2020.
> > + *     This helps switch to BT2020 mode if the BT2020 encoded video stream
> > + *     is being played by the user, same for any other colorspace. Thereby
> > + *     giving a good visual experience to users.
> > + *
> > + *     The expectation from userspace is that it should parse the EDID
> > + *     and get supported colorspaces. Use this property and switch to the
> > + *     one supported. Sink supported colorspaces should be retrieved by
> > + *     userspace from EDID and driver will not explicitly expose them.
> > + *
> > + *     Basically the expectation from userspace is:
> > + *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
> > + *        colorspace
> > + *      - Set this new property to let the sink know what it
> > + *        converted the CRTC output to.
> > + *      - This property is just to inform sink what colorspace
> > + *        source is trying to drive.
> > + *
> > + * Called by a driver the first time it's needed, must be attached to desired
> > + * connectors.
> > + */
> > +int drm_mode_create_colorspace_property(struct drm_connector *connector)
> > +{
> > +	struct drm_device *dev = connector->dev;
> > +	struct drm_property *prop;
> > +
> > +	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
> > +	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
> > +		prop = drm_property_create_enum(dev, DRM_MODE_PROP_ENUM,
> > +						"Colorspace",
> > +						hdmi_colorspaces,
> > +						ARRAY_SIZE(hdmi_colorspaces));
> > +		if (!prop)
> > +			return -ENOMEM;
> > +	} else {
> > +		DRM_DEBUG_KMS("Colorspace property not supported\n");
> > +		return 0;
> > +	}
> > +
> > +	connector->colorspace_property = prop;
> > +
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL(drm_mode_create_colorspace_property);
> > +
> > +/**
> >   * drm_mode_create_content_type_property - create content type property
> >   * @dev: DRM device
> >   *
> > diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
> > index 9941613..29495b3 100644
> > --- a/include/drm/drm_connector.h
> > +++ b/include/drm/drm_connector.h
> > @@ -253,6 +253,38 @@ enum drm_panel_orientation {
> >  	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
> >  };
> >  
> > +/*
> > + * This is a consolidated colorimetry list supported by HDMI and
> > + * DP protocol standard. The respective connectors will register
> > + * a property with the subset of this list (supported by that
> > + * respective protocol). Userspace will set the colorspace through
> > + * a colorspace property which will be created and exposed to
> > + * userspace.
> > + */
> > +
> > +/* For Default case, driver will set the colorspace */
> > +#define DRM_MODE_COLORIMETRY_DEFAULT			0
> > +/* CEA 861 Normal Colorimetry options */
> > +#define DRM_MODE_COLORIMETRY_ITU_601			1
> > +#define DRM_MODE_COLORIMETRY_ITU_709			2
> > +/* CEA 861 Extended Colorimetry Options */
> > +#define DRM_MODE_COLORIMETRY_XV_YCC_601			3
> > +#define DRM_MODE_COLORIMETRY_XV_YCC_709			4
> > +#define DRM_MODE_COLORIMETRY_S_YCC_601			5
> > +#define DRM_MODE_COLORIMETRY_OPYCC_601			6
> > +#define DRM_MODE_COLORIMETRY_OPRGB			7
> > +#define DRM_MODE_COLORIMETRY_BT2020_RGB			8
> > +#define DRM_MODE_COLORIMETRY_BT2020_YCC			9
> > +#define DRM_MODE_COLORIMETRY_BT2020_CYCC		10
> > +/* DP MSA Colorimetry Options */
> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_601		11
> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_709		12
> > +#define DRM_MODE_DP_COLORIMETRY_SRGB			13
> > +#define DRM_MODE_DP_COLORIMETRY_RGB_WIDE_GAMUT		14
> > +#define DRM_MODE_DP_COLORIMETRY_SCRGB			15
> > +#define DRM_MODE_DP_COLORIMETRY_DCI_P3			16
> > +#define DRM_MODE_DP_COLORIMETRY_CUSTOM_COLOR_PROFILE	17
> 
> I think some kind of macro to define these would be good. Assuming we're
> trying directly interpret these as the C/EC/ACE bits. I can't remember
> if multiple enum values can have the same integer value. If not we'd
> also need a YCbCr vs. RGB bit in there somewhere. Assuming we want to
> keep RGB and YCbCr separate. Currently only BT.2020 has a conflict
> between the two.

So I think I'm leaning towards having separate YCbCr vs. RGB values
(which is what you had here already, with BT.2020 being the only
case where that actually matters). That way someone could even do
YCbCr 4:4:4 passthrough by just stuffing YUV data into their RGB
framebuffer (with the components swizzled the right way).

The one thing that rather breaks that usecase is the automagic 4k
YCbCr 4:2:0 fallback. So in in order to guarantee that things
work correctly I guess we still need explcit control over the
output CSC.

Ie. some kind of output color encoding prop like this:
	default /* current behaviour */
	ycbcr BT.601
	ycbcr BT.709
	ycbcr BT.2020
	/* no ycbcr 4:2:0 fallback for below modes? */
	rgb 4:4:4
	ycbcr 4:4:4 BT.601
	ycbcr 4:4:4 BT.709
	ycbcr 4:4:4 BT.2020
	ycbcr 4:2:2 BT.601
	ycbcr 4:2:2 BT.709
	ycbcr 4:2:2 BT.2020
	ycbcr 4:2:0 BT.601
	ycbcr 4:2:0 BT.709
	ycbcr 4:2:0 BT.2020

Hmm. In fact the automagic 4:2:0 fallback sort of breaks the
colorspace prop alredy because if someone set an RGB colorspace
but we end up converting to YCbCr 4:2:0 what should we tell the
sink? Maybe we just reject the modeset in that case and tell
users they need to wait for the output color encoding prop to
support that usecase?

> 
> > +
> >  /**
> >   * struct drm_display_info - runtime data about the connected sink
> >   *
> > @@ -503,6 +535,13 @@ struct drm_connector_state {
> >  	unsigned int content_protection;
> >  
> >  	/**
> > +	 * @colorspace: State variable for Connector property to request
> > +	 * colorspace change on Sink. This is most commonly used to switch
> > +	 * to wider color gamuts like BT2020.
> > +	 */
> > +	u32 colorspace;
> > +
> > +	/**
> >  	 * @writeback_job: Writeback job for writeback connectors
> >  	 *
> >  	 * Holds the framebuffer and out-fence for a writeback connector. As
> > @@ -995,6 +1034,12 @@ struct drm_connector {
> >  	struct drm_property *content_protection_property;
> >  
> >  	/**
> > +	 * @colorspace_property: Connector property to set the suitable
> > +	 * colorspace supported by the sink.
> > +	 */
> > +	struct drm_property *colorspace_property;
> > +
> > +	/**
> >  	 * @path_blob_ptr:
> >  	 *
> >  	 * DRM blob property data for the DP MST path property. This should only
> > @@ -1269,6 +1314,7 @@ int drm_connector_attach_vrr_capable_property(
> >  int drm_connector_attach_content_protection_property(
> >  		struct drm_connector *connector);
> >  int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
> > +int drm_mode_create_colorspace_property(struct drm_connector *connector);
> >  int drm_mode_create_content_type_property(struct drm_device *dev);
> >  void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame,
> >  					 const struct drm_connector_state *conn_state);
> > -- 
> > 1.9.1
> > 
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Ville Syrjälä
> Intel
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Shankar, Uma Feb. 4, 2019, 5:08 p.m. UTC | #3
>-----Original Message-----
>From: Ville Syrjälä [mailto:ville.syrjala@linux.intel.com]
>Sent: Monday, February 4, 2019 8:55 PM
>To: Shankar, Uma <uma.shankar@intel.com>
>Cc: intel-gfx@lists.freedesktop.org; Syrjala, Ville <ville.syrjala@intel.com>;
>Lankhorst, Maarten <maarten.lankhorst@intel.com>; dri-
>devel@lists.freedesktop.org
>Subject: Re: [Intel-gfx] [v10 1/3] drm: Add HDMI colorspace property
>
>On Fri, Feb 01, 2019 at 08:50:11PM +0200, Ville Syrjälä wrote:
>> On Wed, Jan 30, 2019 at 06:24:24PM +0530, Uma Shankar wrote:
>> > Create a new connector property to program colorspace to sink
>> > devices. Modern sink devices support more than 1 type of colorspace
>> > like 601, 709, BT2020 etc. This helps to switch based on content
>> > type which is to be displayed. The decision lies with compositors as
>> > to in which scenarios, a particular colorspace will be picked.
>> >
>> > This will be helpful mostly to switch to higher gamut colorspaces
>> > like BT2020 when the media content is encoded as BT2020. Thereby
>> > giving a good visual experience to users.
>> >
>> > The expectation from userspace is that it should parse the EDID and
>> > get supported colorspaces. Use this property and switch to the one
>> > supported. Sink supported colorspaces should be retrieved by
>> > userspace from EDID and driver will not explicitly expose them.
>> >
>> > Basically the expectation from userspace is:
>> >  - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
>> >    colorspace
>> >  - Set this new property to let the sink know what it
>> >    converted the CRTC output to.
>> >
>> > v2: Addressed Maarten and Ville's review comments. Enhanced the
>> > colorspace enum to incorporate both HDMI and DP supported
>> > colorspaces. Also, added a default option for colorspace.
>> >
>> > v3: Removed Adobe references from enum definitions as per Ville,
>> > Hans Verkuil and Jonas Karlman suggestions. Changed Default to an
>> > unset state where driver will assign the colorspace is not chosen by
>> > user, suggested by Ville and Maarten. Addressed other misc review
>> > comments from Maarten. Split the changes to have separate colorspace
>> > property for DP and HDMI.
>> >
>> > v4: Addressed Chris and Ville's review comments, and created a
>> > common colorspace property for DP and HDMI, filtered the list based
>> > on the colorspaces supported by the respective protocol standard.
>> >
>> > v5: Made the property creation helper accept enum list based on
>> > platform capabilties as suggested by Shashank. Consolidated HDMI and
>> > DP property creation in the common helper.
>> >
>> > v6: Addressed Shashank's review comments.
>> >
>> > v7: Added defines instead of enum in uapi as per Brian Starkey's
>> > suggestion in order to go with string matching at userspace. Updated
>> > the commit message to add more details as well kernel docs.
>> >
>> > v8: Addressed Maarten's review comments.
>> >
>> > v9: Removed macro defines from uapi as per Brian Starkey and Daniel
>> > Stone's comments and moved to drm include file. Moved back to older
>> > design with exposing all HDMI colorspaces to userspace since
>> > infoframe capability is there even on legacy platforms, as per
>> > Ville's review comments.
>> >
>> > v10: Fixed sparse warnings, updated the RB from Maarten and Jani's ack.
>> >
>> > Signed-off-by: Uma Shankar <uma.shankar@intel.com>
>> > Acked-by: Jani Nikula <jani.nikula@intel.com>
>> > Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
>> > Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
>> > ---
>> >  drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
>> >  drivers/gpu/drm/drm_connector.c   | 75
>+++++++++++++++++++++++++++++++++++++++
>> >  include/drm/drm_connector.h       | 46 ++++++++++++++++++++++++
>> >  3 files changed, 125 insertions(+)
>> >
>> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c
>> > b/drivers/gpu/drm/drm_atomic_uapi.c
>> > index 9a1f41a..9b5d44f 100644
>> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
>> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
>> > @@ -746,6 +746,8 @@ static int drm_atomic_connector_set_property(struct
>drm_connector *connector,
>> >  			return -EINVAL;
>> >  		}
>> >  		state->content_protection = val;
>> > +	} else if (property == connector->colorspace_property) {
>> > +		state->colorspace = val;
>> >  	} else if (property == config->writeback_fb_id_property) {
>> >  		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev,
>NULL, val);
>> >  		int ret = drm_atomic_set_writeback_fb_for_connector(state,
>fb);
>> > @@ -814,6 +816,8 @@ static int drm_atomic_connector_set_property(struct
>drm_connector *connector,
>> >  		*val = state->picture_aspect_ratio;
>> >  	} else if (property == config->content_type_property) {
>> >  		*val = state->content_type;
>> > +	} else if (property == connector->colorspace_property) {
>> > +		*val = state->colorspace;
>> >  	} else if (property == connector->scaling_mode_property) {
>> >  		*val = state->scaling_mode;
>> >  	} else if (property == connector->content_protection_property) {
>> > diff --git a/drivers/gpu/drm/drm_connector.c
>> > b/drivers/gpu/drm/drm_connector.c index 8475396..ed10dd9 100644
>> > --- a/drivers/gpu/drm/drm_connector.c
>> > +++ b/drivers/gpu/drm/drm_connector.c
>> > @@ -826,6 +826,30 @@ int drm_display_info_set_bus_formats(struct
>> > drm_display_info *info,  };
>> > DRM_ENUM_NAME_FN(drm_get_content_protection_name,
>drm_cp_enum_list)
>> >
>> > +static const struct drm_prop_enum_list hdmi_colorspaces[] = {
>> > +	/* For Default case, driver will set the colorspace */
>> > +	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
>> > +	/* Standard Definition Colorimetry based on CEA 861 */
>> > +	{ DRM_MODE_COLORIMETRY_ITU_601, "ITU_601" },
>>
>> The spec no longer has the BT.601 note here. Which I guess makes sense
>> since BT.601 didn't even specify any color primaries initially. Later
>> versions do by they have distinct primaries for NTSC vs. PAL. The spec
>> calls this just SMPTE 170M now, so I think we should do the same.

Ok Sure, Will update this name. Yeah this was a little confusing as to what name to
go with. Will take the one defined now in spec i.e., SMPTE 170M.

>>
>> > +	{ DRM_MODE_COLORIMETRY_ITU_709, "ITU_709" },
>> > +	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
>> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_601, "XV_YCC_601" },
>> > +	/* High Definition Colorimetry based on IEC 61966-2-4 */
>> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_709, "XV_YCC_709" },
>> > +	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
>> > +	{ DRM_MODE_COLORIMETRY_S_YCC_601, "S_YCC_601" },
>> > +	/* Colorimetry based on IEC 61966-2-5 [33] */
>> > +	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
>>
>> The spelling is rather inconsistent here. XV_ vs. S_ vs. op. Why not
>> use the same spelling style for all?

This is the names defined in spec and I used as is. I will make them  as
XVYCC, SYCC and OPYCC for consistency. Hope this is ok ?

>>
>> > +	/* Colorimetry based on IEC 61966-2-5 */
>> > +	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
>> > +	/* Colorimetry based on ITU-R BT.2020 */
>> > +	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
>> > +	/* Colorimetry based on ITU-R BT.2020 */
>> > +	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
>> > +	/* Colorimetry based on ITU-R BT.2020 */
>> > +	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
>>
>> "BT2020" vs. "ITU_709" is rather inconsistent as well.

Ok, will update this.

>> We also seem to be missing the two DCI-P3 things here.

Yeah, I initially did as per 861.F where it was not there. This got added in 861.G,
will  add this.

>> > +};
>> > +
>> >  /**
>> >   * DOC: standard connector properties
>> >   *
>> > @@ -1548,6 +1572,57 @@ int
>> > drm_mode_create_aspect_ratio_property(struct drm_device *dev)
>> > EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
>> >
>> >  /**
>> > + * DOC: standard connector properties
>> > + *
>> > + * Colorspace:
>> > + *     drm_mode_create_colorspace_property - create colorspace property
>> > + *     This property helps select a suitable colorspace based on the sink
>> > + *     capability. Modern sink devices support wider gamut like BT2020.
>> > + *     This helps switch to BT2020 mode if the BT2020 encoded video stream
>> > + *     is being played by the user, same for any other colorspace. Thereby
>> > + *     giving a good visual experience to users.
>> > + *
>> > + *     The expectation from userspace is that it should parse the EDID
>> > + *     and get supported colorspaces. Use this property and switch to the
>> > + *     one supported. Sink supported colorspaces should be retrieved by
>> > + *     userspace from EDID and driver will not explicitly expose them.
>> > + *
>> > + *     Basically the expectation from userspace is:
>> > + *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
>> > + *        colorspace
>> > + *      - Set this new property to let the sink know what it
>> > + *        converted the CRTC output to.
>> > + *      - This property is just to inform sink what colorspace
>> > + *        source is trying to drive.
>> > + *
>> > + * Called by a driver the first time it's needed, must be attached
>> > +to desired
>> > + * connectors.
>> > + */
>> > +int drm_mode_create_colorspace_property(struct drm_connector
>> > +*connector) {
>> > +	struct drm_device *dev = connector->dev;
>> > +	struct drm_property *prop;
>> > +
>> > +	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
>> > +	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
>> > +		prop = drm_property_create_enum(dev,
>DRM_MODE_PROP_ENUM,
>> > +						"Colorspace",
>> > +						hdmi_colorspaces,
>> > +
>	ARRAY_SIZE(hdmi_colorspaces));
>> > +		if (!prop)
>> > +			return -ENOMEM;
>> > +	} else {
>> > +		DRM_DEBUG_KMS("Colorspace property not supported\n");
>> > +		return 0;
>> > +	}
>> > +
>> > +	connector->colorspace_property = prop;
>> > +
>> > +	return 0;
>> > +}
>> > +EXPORT_SYMBOL(drm_mode_create_colorspace_property);
>> > +
>> > +/**
>> >   * drm_mode_create_content_type_property - create content type property
>> >   * @dev: DRM device
>> >   *
>> > diff --git a/include/drm/drm_connector.h
>> > b/include/drm/drm_connector.h index 9941613..29495b3 100644
>> > --- a/include/drm/drm_connector.h
>> > +++ b/include/drm/drm_connector.h
>> > @@ -253,6 +253,38 @@ enum drm_panel_orientation {
>> >  	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
>> >  };
>> >
>> > +/*
>> > + * This is a consolidated colorimetry list supported by HDMI and
>> > + * DP protocol standard. The respective connectors will register
>> > + * a property with the subset of this list (supported by that
>> > + * respective protocol). Userspace will set the colorspace through
>> > + * a colorspace property which will be created and exposed to
>> > + * userspace.
>> > + */
>> > +
>> > +/* For Default case, driver will set the colorspace */
>> > +#define DRM_MODE_COLORIMETRY_DEFAULT			0
>> > +/* CEA 861 Normal Colorimetry options */
>> > +#define DRM_MODE_COLORIMETRY_ITU_601			1
>> > +#define DRM_MODE_COLORIMETRY_ITU_709			2
>> > +/* CEA 861 Extended Colorimetry Options */
>> > +#define DRM_MODE_COLORIMETRY_XV_YCC_601			3
>> > +#define DRM_MODE_COLORIMETRY_XV_YCC_709			4
>> > +#define DRM_MODE_COLORIMETRY_S_YCC_601			5
>> > +#define DRM_MODE_COLORIMETRY_OPYCC_601			6
>> > +#define DRM_MODE_COLORIMETRY_OPRGB			7
>> > +#define DRM_MODE_COLORIMETRY_BT2020_RGB			8
>> > +#define DRM_MODE_COLORIMETRY_BT2020_YCC			9
>> > +#define DRM_MODE_COLORIMETRY_BT2020_CYCC		10
>> > +/* DP MSA Colorimetry Options */
>> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_601		11
>> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_709		12
>> > +#define DRM_MODE_DP_COLORIMETRY_SRGB			13
>> > +#define DRM_MODE_DP_COLORIMETRY_RGB_WIDE_GAMUT
>	14
>> > +#define DRM_MODE_DP_COLORIMETRY_SCRGB			15
>> > +#define DRM_MODE_DP_COLORIMETRY_DCI_P3			16
>> > +#define DRM_MODE_DP_COLORIMETRY_CUSTOM_COLOR_PROFILE
>	17
>>
>> I think some kind of macro to define these would be good. Assuming
>> we're trying directly interpret these as the C/EC/ACE bits. I can't
>> remember if multiple enum values can have the same integer value. If
>> not we'd also need a YCbCr vs. RGB bit in there somewhere. Assuming we
>> want to keep RGB and YCbCr separate. Currently only BT.2020 has a
>> conflict between the two.
>
>So I think I'm leaning towards having separate YCbCr vs. RGB values (which is
>what you had here already, with BT.2020 being the only case where that actually
>matters). That way someone could even do YCbCr 4:4:4 passthrough by just
>stuffing YUV data into their RGB framebuffer (with the components swizzled the
>right way).
>
>The one thing that rather breaks that usecase is the automagic 4k YCbCr 4:2:0
>fallback. So in in order to guarantee that things work correctly I guess we still
>need explcit control over the output CSC.
>
>Ie. some kind of output color encoding prop like this:
>	default /* current behaviour */
>	ycbcr BT.601
>	ycbcr BT.709
>	ycbcr BT.2020
>	/* no ycbcr 4:2:0 fallback for below modes? */
>	rgb 4:4:4
>	ycbcr 4:4:4 BT.601
>	ycbcr 4:4:4 BT.709
>	ycbcr 4:4:4 BT.2020
>	ycbcr 4:2:2 BT.601
>	ycbcr 4:2:2 BT.709
>	ycbcr 4:2:2 BT.2020
>	ycbcr 4:2:0 BT.601
>	ycbcr 4:2:0 BT.709
>	ycbcr 4:2:0 BT.2020
>
>Hmm. In fact the automagic 4:2:0 fallback sort of breaks the colorspace prop
>alredy because if someone set an RGB colorspace but we end up converting to
>YCbCr 4:2:0 what should we tell the sink? Maybe we just reject the modeset in
>that case and tell users they need to wait for the output color encoding prop to
>support that usecase?

Hi yes, an output encoding property to control this make sense and will be useful.
So if a user decides to have a RGB buffer at source or wants to blend multiple layers in RGB,
and still want o/p converted to YUV420 at o/p, he can use the current colorspace property to
set that and send to sink. In case he doesn't do it explicitly we can still let the content be driven
but with warnings or choose to fail his modeset if that seems better.

What do you suggest, should we keep current property interface like this and extend the usage
with a separate property on top of it.

Thanks Ville for your review comments and suggestions.

Regards,
Uma Shankar

>
>>
>> > +
>> >  /**
>> >   * struct drm_display_info - runtime data about the connected sink
>> >   *
>> > @@ -503,6 +535,13 @@ struct drm_connector_state {
>> >  	unsigned int content_protection;
>> >
>> >  	/**
>> > +	 * @colorspace: State variable for Connector property to request
>> > +	 * colorspace change on Sink. This is most commonly used to switch
>> > +	 * to wider color gamuts like BT2020.
>> > +	 */
>> > +	u32 colorspace;
>> > +
>> > +	/**
>> >  	 * @writeback_job: Writeback job for writeback connectors
>> >  	 *
>> >  	 * Holds the framebuffer and out-fence for a writeback connector.
>> > As @@ -995,6 +1034,12 @@ struct drm_connector {
>> >  	struct drm_property *content_protection_property;
>> >
>> >  	/**
>> > +	 * @colorspace_property: Connector property to set the suitable
>> > +	 * colorspace supported by the sink.
>> > +	 */
>> > +	struct drm_property *colorspace_property;
>> > +
>> > +	/**
>> >  	 * @path_blob_ptr:
>> >  	 *
>> >  	 * DRM blob property data for the DP MST path property. This
>> > should only @@ -1269,6 +1314,7 @@ int
>> > drm_connector_attach_vrr_capable_property(
>> >  int drm_connector_attach_content_protection_property(
>> >  		struct drm_connector *connector);  int
>> > drm_mode_create_aspect_ratio_property(struct drm_device *dev);
>> > +int drm_mode_create_colorspace_property(struct drm_connector
>> > +*connector);
>> >  int drm_mode_create_content_type_property(struct drm_device *dev);
>> > void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe
>*frame,
>> >  					 const struct drm_connector_state
>*conn_state);
>> > --
>> > 1.9.1
>> >
>> > _______________________________________________
>> > Intel-gfx mailing list
>> > Intel-gfx@lists.freedesktop.org
>> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>>
>> --
>> Ville Syrjälä
>> Intel
>> _______________________________________________
>> Intel-gfx mailing list
>> Intel-gfx@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
>--
>Ville Syrjälä
>Intel
Ville Syrjala Feb. 4, 2019, 5:24 p.m. UTC | #4
On Mon, Feb 04, 2019 at 05:08:40PM +0000, Shankar, Uma wrote:
> 
> 
> >-----Original Message-----
> >From: Ville Syrjälä [mailto:ville.syrjala@linux.intel.com]
> >Sent: Monday, February 4, 2019 8:55 PM
> >To: Shankar, Uma <uma.shankar@intel.com>
> >Cc: intel-gfx@lists.freedesktop.org; Syrjala, Ville <ville.syrjala@intel.com>;
> >Lankhorst, Maarten <maarten.lankhorst@intel.com>; dri-
> >devel@lists.freedesktop.org
> >Subject: Re: [Intel-gfx] [v10 1/3] drm: Add HDMI colorspace property
> >
> >On Fri, Feb 01, 2019 at 08:50:11PM +0200, Ville Syrjälä wrote:
> >> On Wed, Jan 30, 2019 at 06:24:24PM +0530, Uma Shankar wrote:
> >> > Create a new connector property to program colorspace to sink
> >> > devices. Modern sink devices support more than 1 type of colorspace
> >> > like 601, 709, BT2020 etc. This helps to switch based on content
> >> > type which is to be displayed. The decision lies with compositors as
> >> > to in which scenarios, a particular colorspace will be picked.
> >> >
> >> > This will be helpful mostly to switch to higher gamut colorspaces
> >> > like BT2020 when the media content is encoded as BT2020. Thereby
> >> > giving a good visual experience to users.
> >> >
> >> > The expectation from userspace is that it should parse the EDID and
> >> > get supported colorspaces. Use this property and switch to the one
> >> > supported. Sink supported colorspaces should be retrieved by
> >> > userspace from EDID and driver will not explicitly expose them.
> >> >
> >> > Basically the expectation from userspace is:
> >> >  - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
> >> >    colorspace
> >> >  - Set this new property to let the sink know what it
> >> >    converted the CRTC output to.
> >> >
> >> > v2: Addressed Maarten and Ville's review comments. Enhanced the
> >> > colorspace enum to incorporate both HDMI and DP supported
> >> > colorspaces. Also, added a default option for colorspace.
> >> >
> >> > v3: Removed Adobe references from enum definitions as per Ville,
> >> > Hans Verkuil and Jonas Karlman suggestions. Changed Default to an
> >> > unset state where driver will assign the colorspace is not chosen by
> >> > user, suggested by Ville and Maarten. Addressed other misc review
> >> > comments from Maarten. Split the changes to have separate colorspace
> >> > property for DP and HDMI.
> >> >
> >> > v4: Addressed Chris and Ville's review comments, and created a
> >> > common colorspace property for DP and HDMI, filtered the list based
> >> > on the colorspaces supported by the respective protocol standard.
> >> >
> >> > v5: Made the property creation helper accept enum list based on
> >> > platform capabilties as suggested by Shashank. Consolidated HDMI and
> >> > DP property creation in the common helper.
> >> >
> >> > v6: Addressed Shashank's review comments.
> >> >
> >> > v7: Added defines instead of enum in uapi as per Brian Starkey's
> >> > suggestion in order to go with string matching at userspace. Updated
> >> > the commit message to add more details as well kernel docs.
> >> >
> >> > v8: Addressed Maarten's review comments.
> >> >
> >> > v9: Removed macro defines from uapi as per Brian Starkey and Daniel
> >> > Stone's comments and moved to drm include file. Moved back to older
> >> > design with exposing all HDMI colorspaces to userspace since
> >> > infoframe capability is there even on legacy platforms, as per
> >> > Ville's review comments.
> >> >
> >> > v10: Fixed sparse warnings, updated the RB from Maarten and Jani's ack.
> >> >
> >> > Signed-off-by: Uma Shankar <uma.shankar@intel.com>
> >> > Acked-by: Jani Nikula <jani.nikula@intel.com>
> >> > Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
> >> > Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> >> > ---
> >> >  drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
> >> >  drivers/gpu/drm/drm_connector.c   | 75
> >+++++++++++++++++++++++++++++++++++++++
> >> >  include/drm/drm_connector.h       | 46 ++++++++++++++++++++++++
> >> >  3 files changed, 125 insertions(+)
> >> >
> >> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c
> >> > b/drivers/gpu/drm/drm_atomic_uapi.c
> >> > index 9a1f41a..9b5d44f 100644
> >> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
> >> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> >> > @@ -746,6 +746,8 @@ static int drm_atomic_connector_set_property(struct
> >drm_connector *connector,
> >> >  			return -EINVAL;
> >> >  		}
> >> >  		state->content_protection = val;
> >> > +	} else if (property == connector->colorspace_property) {
> >> > +		state->colorspace = val;
> >> >  	} else if (property == config->writeback_fb_id_property) {
> >> >  		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev,
> >NULL, val);
> >> >  		int ret = drm_atomic_set_writeback_fb_for_connector(state,
> >fb);
> >> > @@ -814,6 +816,8 @@ static int drm_atomic_connector_set_property(struct
> >drm_connector *connector,
> >> >  		*val = state->picture_aspect_ratio;
> >> >  	} else if (property == config->content_type_property) {
> >> >  		*val = state->content_type;
> >> > +	} else if (property == connector->colorspace_property) {
> >> > +		*val = state->colorspace;
> >> >  	} else if (property == connector->scaling_mode_property) {
> >> >  		*val = state->scaling_mode;
> >> >  	} else if (property == connector->content_protection_property) {
> >> > diff --git a/drivers/gpu/drm/drm_connector.c
> >> > b/drivers/gpu/drm/drm_connector.c index 8475396..ed10dd9 100644
> >> > --- a/drivers/gpu/drm/drm_connector.c
> >> > +++ b/drivers/gpu/drm/drm_connector.c
> >> > @@ -826,6 +826,30 @@ int drm_display_info_set_bus_formats(struct
> >> > drm_display_info *info,  };
> >> > DRM_ENUM_NAME_FN(drm_get_content_protection_name,
> >drm_cp_enum_list)
> >> >
> >> > +static const struct drm_prop_enum_list hdmi_colorspaces[] = {
> >> > +	/* For Default case, driver will set the colorspace */
> >> > +	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
> >> > +	/* Standard Definition Colorimetry based on CEA 861 */
> >> > +	{ DRM_MODE_COLORIMETRY_ITU_601, "ITU_601" },
> >>
> >> The spec no longer has the BT.601 note here. Which I guess makes sense
> >> since BT.601 didn't even specify any color primaries initially. Later
> >> versions do by they have distinct primaries for NTSC vs. PAL. The spec
> >> calls this just SMPTE 170M now, so I think we should do the same.
> 
> Ok Sure, Will update this name. Yeah this was a little confusing as to what name to
> go with. Will take the one defined now in spec i.e., SMPTE 170M.
> 
> >>
> >> > +	{ DRM_MODE_COLORIMETRY_ITU_709, "ITU_709" },
> >> > +	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
> >> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_601, "XV_YCC_601" },
> >> > +	/* High Definition Colorimetry based on IEC 61966-2-4 */
> >> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_709, "XV_YCC_709" },
> >> > +	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
> >> > +	{ DRM_MODE_COLORIMETRY_S_YCC_601, "S_YCC_601" },
> >> > +	/* Colorimetry based on IEC 61966-2-5 [33] */
> >> > +	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
> >>
> >> The spelling is rather inconsistent here. XV_ vs. S_ vs. op. Why not
> >> use the same spelling style for all?
> 
> This is the names defined in spec and I used as is. I will make them  as
> XVYCC, SYCC and OPYCC for consistency. Hope this is ok ?
> 
> >>
> >> > +	/* Colorimetry based on IEC 61966-2-5 */
> >> > +	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
> >> > +	/* Colorimetry based on ITU-R BT.2020 */
> >> > +	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
> >> > +	/* Colorimetry based on ITU-R BT.2020 */
> >> > +	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
> >> > +	/* Colorimetry based on ITU-R BT.2020 */
> >> > +	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
> >>
> >> "BT2020" vs. "ITU_709" is rather inconsistent as well.
> 
> Ok, will update this.
> 
> >> We also seem to be missing the two DCI-P3 things here.
> 
> Yeah, I initially did as per 861.F where it was not there. This got added in 861.G,
> will  add this.
> 
> >> > +};
> >> > +
> >> >  /**
> >> >   * DOC: standard connector properties
> >> >   *
> >> > @@ -1548,6 +1572,57 @@ int
> >> > drm_mode_create_aspect_ratio_property(struct drm_device *dev)
> >> > EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
> >> >
> >> >  /**
> >> > + * DOC: standard connector properties
> >> > + *
> >> > + * Colorspace:
> >> > + *     drm_mode_create_colorspace_property - create colorspace property
> >> > + *     This property helps select a suitable colorspace based on the sink
> >> > + *     capability. Modern sink devices support wider gamut like BT2020.
> >> > + *     This helps switch to BT2020 mode if the BT2020 encoded video stream
> >> > + *     is being played by the user, same for any other colorspace. Thereby
> >> > + *     giving a good visual experience to users.
> >> > + *
> >> > + *     The expectation from userspace is that it should parse the EDID
> >> > + *     and get supported colorspaces. Use this property and switch to the
> >> > + *     one supported. Sink supported colorspaces should be retrieved by
> >> > + *     userspace from EDID and driver will not explicitly expose them.
> >> > + *
> >> > + *     Basically the expectation from userspace is:
> >> > + *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
> >> > + *        colorspace
> >> > + *      - Set this new property to let the sink know what it
> >> > + *        converted the CRTC output to.
> >> > + *      - This property is just to inform sink what colorspace
> >> > + *        source is trying to drive.
> >> > + *
> >> > + * Called by a driver the first time it's needed, must be attached
> >> > +to desired
> >> > + * connectors.
> >> > + */
> >> > +int drm_mode_create_colorspace_property(struct drm_connector
> >> > +*connector) {
> >> > +	struct drm_device *dev = connector->dev;
> >> > +	struct drm_property *prop;
> >> > +
> >> > +	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
> >> > +	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
> >> > +		prop = drm_property_create_enum(dev,
> >DRM_MODE_PROP_ENUM,
> >> > +						"Colorspace",
> >> > +						hdmi_colorspaces,
> >> > +
> >	ARRAY_SIZE(hdmi_colorspaces));
> >> > +		if (!prop)
> >> > +			return -ENOMEM;
> >> > +	} else {
> >> > +		DRM_DEBUG_KMS("Colorspace property not supported\n");
> >> > +		return 0;
> >> > +	}
> >> > +
> >> > +	connector->colorspace_property = prop;
> >> > +
> >> > +	return 0;
> >> > +}
> >> > +EXPORT_SYMBOL(drm_mode_create_colorspace_property);
> >> > +
> >> > +/**
> >> >   * drm_mode_create_content_type_property - create content type property
> >> >   * @dev: DRM device
> >> >   *
> >> > diff --git a/include/drm/drm_connector.h
> >> > b/include/drm/drm_connector.h index 9941613..29495b3 100644
> >> > --- a/include/drm/drm_connector.h
> >> > +++ b/include/drm/drm_connector.h
> >> > @@ -253,6 +253,38 @@ enum drm_panel_orientation {
> >> >  	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
> >> >  };
> >> >
> >> > +/*
> >> > + * This is a consolidated colorimetry list supported by HDMI and
> >> > + * DP protocol standard. The respective connectors will register
> >> > + * a property with the subset of this list (supported by that
> >> > + * respective protocol). Userspace will set the colorspace through
> >> > + * a colorspace property which will be created and exposed to
> >> > + * userspace.
> >> > + */
> >> > +
> >> > +/* For Default case, driver will set the colorspace */
> >> > +#define DRM_MODE_COLORIMETRY_DEFAULT			0
> >> > +/* CEA 861 Normal Colorimetry options */
> >> > +#define DRM_MODE_COLORIMETRY_ITU_601			1
> >> > +#define DRM_MODE_COLORIMETRY_ITU_709			2
> >> > +/* CEA 861 Extended Colorimetry Options */
> >> > +#define DRM_MODE_COLORIMETRY_XV_YCC_601			3
> >> > +#define DRM_MODE_COLORIMETRY_XV_YCC_709			4
> >> > +#define DRM_MODE_COLORIMETRY_S_YCC_601			5
> >> > +#define DRM_MODE_COLORIMETRY_OPYCC_601			6
> >> > +#define DRM_MODE_COLORIMETRY_OPRGB			7
> >> > +#define DRM_MODE_COLORIMETRY_BT2020_RGB			8
> >> > +#define DRM_MODE_COLORIMETRY_BT2020_YCC			9
> >> > +#define DRM_MODE_COLORIMETRY_BT2020_CYCC		10
> >> > +/* DP MSA Colorimetry Options */
> >> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_601		11
> >> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_709		12
> >> > +#define DRM_MODE_DP_COLORIMETRY_SRGB			13
> >> > +#define DRM_MODE_DP_COLORIMETRY_RGB_WIDE_GAMUT
> >	14
> >> > +#define DRM_MODE_DP_COLORIMETRY_SCRGB			15
> >> > +#define DRM_MODE_DP_COLORIMETRY_DCI_P3			16
> >> > +#define DRM_MODE_DP_COLORIMETRY_CUSTOM_COLOR_PROFILE
> >	17
> >>
> >> I think some kind of macro to define these would be good. Assuming
> >> we're trying directly interpret these as the C/EC/ACE bits. I can't
> >> remember if multiple enum values can have the same integer value. If
> >> not we'd also need a YCbCr vs. RGB bit in there somewhere. Assuming we
> >> want to keep RGB and YCbCr separate. Currently only BT.2020 has a
> >> conflict between the two.
> >
> >So I think I'm leaning towards having separate YCbCr vs. RGB values (which is
> >what you had here already, with BT.2020 being the only case where that actually
> >matters). That way someone could even do YCbCr 4:4:4 passthrough by just
> >stuffing YUV data into their RGB framebuffer (with the components swizzled the
> >right way).
> >
> >The one thing that rather breaks that usecase is the automagic 4k YCbCr 4:2:0
> >fallback. So in in order to guarantee that things work correctly I guess we still
> >need explcit control over the output CSC.
> >
> >Ie. some kind of output color encoding prop like this:
> >	default /* current behaviour */
> >	ycbcr BT.601
> >	ycbcr BT.709
> >	ycbcr BT.2020
> >	/* no ycbcr 4:2:0 fallback for below modes? */
> >	rgb 4:4:4
> >	ycbcr 4:4:4 BT.601
> >	ycbcr 4:4:4 BT.709
> >	ycbcr 4:4:4 BT.2020
> >	ycbcr 4:2:2 BT.601
> >	ycbcr 4:2:2 BT.709
> >	ycbcr 4:2:2 BT.2020
> >	ycbcr 4:2:0 BT.601
> >	ycbcr 4:2:0 BT.709
> >	ycbcr 4:2:0 BT.2020
> >
> >Hmm. In fact the automagic 4:2:0 fallback sort of breaks the colorspace prop
> >alredy because if someone set an RGB colorspace but we end up converting to
> >YCbCr 4:2:0 what should we tell the sink? Maybe we just reject the modeset in
> >that case and tell users they need to wait for the output color encoding prop to
> >support that usecase?
> 
> Hi yes, an output encoding property to control this make sense and will be useful.
> So if a user decides to have a RGB buffer at source or wants to blend multiple layers in RGB,
> and still want o/p converted to YUV420 at o/p, he can use the current colorspace property to
> set that and send to sink. In case he doesn't do it explicitly we can still let the content be driven
> but with warnings or choose to fail his modeset if that seems better.
> 
> What do you suggest, should we keep current property interface like this and extend the usage
> with a separate property on top of it.

I think separate prop to control the output CSC is best. The
colorspace prop should only control the infoframe. If the
two are in violent disagreement we can fail the modeset.

> 
> Thanks Ville for your review comments and suggestions.
> 
> Regards,
> Uma Shankar
> 
> >
> >>
> >> > +
> >> >  /**
> >> >   * struct drm_display_info - runtime data about the connected sink
> >> >   *
> >> > @@ -503,6 +535,13 @@ struct drm_connector_state {
> >> >  	unsigned int content_protection;
> >> >
> >> >  	/**
> >> > +	 * @colorspace: State variable for Connector property to request
> >> > +	 * colorspace change on Sink. This is most commonly used to switch
> >> > +	 * to wider color gamuts like BT2020.
> >> > +	 */
> >> > +	u32 colorspace;
> >> > +
> >> > +	/**
> >> >  	 * @writeback_job: Writeback job for writeback connectors
> >> >  	 *
> >> >  	 * Holds the framebuffer and out-fence for a writeback connector.
> >> > As @@ -995,6 +1034,12 @@ struct drm_connector {
> >> >  	struct drm_property *content_protection_property;
> >> >
> >> >  	/**
> >> > +	 * @colorspace_property: Connector property to set the suitable
> >> > +	 * colorspace supported by the sink.
> >> > +	 */
> >> > +	struct drm_property *colorspace_property;
> >> > +
> >> > +	/**
> >> >  	 * @path_blob_ptr:
> >> >  	 *
> >> >  	 * DRM blob property data for the DP MST path property. This
> >> > should only @@ -1269,6 +1314,7 @@ int
> >> > drm_connector_attach_vrr_capable_property(
> >> >  int drm_connector_attach_content_protection_property(
> >> >  		struct drm_connector *connector);  int
> >> > drm_mode_create_aspect_ratio_property(struct drm_device *dev);
> >> > +int drm_mode_create_colorspace_property(struct drm_connector
> >> > +*connector);
> >> >  int drm_mode_create_content_type_property(struct drm_device *dev);
> >> > void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe
> >*frame,
> >> >  					 const struct drm_connector_state
> >*conn_state);
> >> > --
> >> > 1.9.1
> >> >
> >> > _______________________________________________
> >> > Intel-gfx mailing list
> >> > Intel-gfx@lists.freedesktop.org
> >> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> >>
> >> --
> >> Ville Syrjälä
> >> Intel
> >> _______________________________________________
> >> Intel-gfx mailing list
> >> Intel-gfx@lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> >
> >--
> >Ville Syrjälä
> >Intel
Shankar, Uma Feb. 4, 2019, 6:16 p.m. UTC | #5
>-----Original Message-----
>From: dri-devel [mailto:dri-devel-bounces@lists.freedesktop.org] On Behalf Of
>Ville Syrjälä
>Sent: Monday, February 4, 2019 10:54 PM
>To: Shankar, Uma <uma.shankar@intel.com>
>Cc: intel-gfx@lists.freedesktop.org; Syrjala, Ville <ville.syrjala@intel.com>; dri-
>devel@lists.freedesktop.org; Lankhorst, Maarten
><maarten.lankhorst@intel.com>
>Subject: Re: [Intel-gfx] [v10 1/3] drm: Add HDMI colorspace property
>
>On Mon, Feb 04, 2019 at 05:08:40PM +0000, Shankar, Uma wrote:
>>
>>
>> >-----Original Message-----
>> >From: Ville Syrjälä [mailto:ville.syrjala@linux.intel.com]
>> >Sent: Monday, February 4, 2019 8:55 PM
>> >To: Shankar, Uma <uma.shankar@intel.com>
>> >Cc: intel-gfx@lists.freedesktop.org; Syrjala, Ville
>> ><ville.syrjala@intel.com>; Lankhorst, Maarten
>> ><maarten.lankhorst@intel.com>; dri- devel@lists.freedesktop.org
>> >Subject: Re: [Intel-gfx] [v10 1/3] drm: Add HDMI colorspace property
>> >
>> >On Fri, Feb 01, 2019 at 08:50:11PM +0200, Ville Syrjälä wrote:
>> >> On Wed, Jan 30, 2019 at 06:24:24PM +0530, Uma Shankar wrote:
>> >> > Create a new connector property to program colorspace to sink
>> >> > devices. Modern sink devices support more than 1 type of
>> >> > colorspace like 601, 709, BT2020 etc. This helps to switch based
>> >> > on content type which is to be displayed. The decision lies with
>> >> > compositors as to in which scenarios, a particular colorspace will be
>picked.
>> >> >
>> >> > This will be helpful mostly to switch to higher gamut colorspaces
>> >> > like BT2020 when the media content is encoded as BT2020. Thereby
>> >> > giving a good visual experience to users.
>> >> >
>> >> > The expectation from userspace is that it should parse the EDID
>> >> > and get supported colorspaces. Use this property and switch to
>> >> > the one supported. Sink supported colorspaces should be retrieved
>> >> > by userspace from EDID and driver will not explicitly expose them.
>> >> >
>> >> > Basically the expectation from userspace is:
>> >> >  - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
>> >> >    colorspace
>> >> >  - Set this new property to let the sink know what it
>> >> >    converted the CRTC output to.
>> >> >
>> >> > v2: Addressed Maarten and Ville's review comments. Enhanced the
>> >> > colorspace enum to incorporate both HDMI and DP supported
>> >> > colorspaces. Also, added a default option for colorspace.
>> >> >
>> >> > v3: Removed Adobe references from enum definitions as per Ville,
>> >> > Hans Verkuil and Jonas Karlman suggestions. Changed Default to an
>> >> > unset state where driver will assign the colorspace is not chosen
>> >> > by user, suggested by Ville and Maarten. Addressed other misc
>> >> > review comments from Maarten. Split the changes to have separate
>> >> > colorspace property for DP and HDMI.
>> >> >
>> >> > v4: Addressed Chris and Ville's review comments, and created a
>> >> > common colorspace property for DP and HDMI, filtered the list
>> >> > based on the colorspaces supported by the respective protocol standard.
>> >> >
>> >> > v5: Made the property creation helper accept enum list based on
>> >> > platform capabilties as suggested by Shashank. Consolidated HDMI
>> >> > and DP property creation in the common helper.
>> >> >
>> >> > v6: Addressed Shashank's review comments.
>> >> >
>> >> > v7: Added defines instead of enum in uapi as per Brian Starkey's
>> >> > suggestion in order to go with string matching at userspace.
>> >> > Updated the commit message to add more details as well kernel docs.
>> >> >
>> >> > v8: Addressed Maarten's review comments.
>> >> >
>> >> > v9: Removed macro defines from uapi as per Brian Starkey and
>> >> > Daniel Stone's comments and moved to drm include file. Moved back
>> >> > to older design with exposing all HDMI colorspaces to userspace
>> >> > since infoframe capability is there even on legacy platforms, as
>> >> > per Ville's review comments.
>> >> >
>> >> > v10: Fixed sparse warnings, updated the RB from Maarten and Jani's ack.
>> >> >
>> >> > Signed-off-by: Uma Shankar <uma.shankar@intel.com>
>> >> > Acked-by: Jani Nikula <jani.nikula@intel.com>
>> >> > Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
>> >> > Reviewed-by: Maarten Lankhorst
>> >> > <maarten.lankhorst@linux.intel.com>
>> >> > ---
>> >> >  drivers/gpu/drm/drm_atomic_uapi.c |  4 +++
>> >> >  drivers/gpu/drm/drm_connector.c   | 75
>> >+++++++++++++++++++++++++++++++++++++++
>> >> >  include/drm/drm_connector.h       | 46 ++++++++++++++++++++++++
>> >> >  3 files changed, 125 insertions(+)
>> >> >
>> >> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c
>> >> > b/drivers/gpu/drm/drm_atomic_uapi.c
>> >> > index 9a1f41a..9b5d44f 100644
>> >> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
>> >> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
>> >> > @@ -746,6 +746,8 @@ static int
>> >> > drm_atomic_connector_set_property(struct
>> >drm_connector *connector,
>> >> >  			return -EINVAL;
>> >> >  		}
>> >> >  		state->content_protection = val;
>> >> > +	} else if (property == connector->colorspace_property) {
>> >> > +		state->colorspace = val;
>> >> >  	} else if (property == config->writeback_fb_id_property) {
>> >> >  		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev,
>> >NULL, val);
>> >> >  		int ret = drm_atomic_set_writeback_fb_for_connector(state,
>> >fb);
>> >> > @@ -814,6 +816,8 @@ static int
>> >> > drm_atomic_connector_set_property(struct
>> >drm_connector *connector,
>> >> >  		*val = state->picture_aspect_ratio;
>> >> >  	} else if (property == config->content_type_property) {
>> >> >  		*val = state->content_type;
>> >> > +	} else if (property == connector->colorspace_property) {
>> >> > +		*val = state->colorspace;
>> >> >  	} else if (property == connector->scaling_mode_property) {
>> >> >  		*val = state->scaling_mode;
>> >> >  	} else if (property == connector->content_protection_property)
>> >> > { diff --git a/drivers/gpu/drm/drm_connector.c
>> >> > b/drivers/gpu/drm/drm_connector.c index 8475396..ed10dd9 100644
>> >> > --- a/drivers/gpu/drm/drm_connector.c
>> >> > +++ b/drivers/gpu/drm/drm_connector.c
>> >> > @@ -826,6 +826,30 @@ int drm_display_info_set_bus_formats(struct
>> >> > drm_display_info *info,  };
>> >> > DRM_ENUM_NAME_FN(drm_get_content_protection_name,
>> >drm_cp_enum_list)
>> >> >
>> >> > +static const struct drm_prop_enum_list hdmi_colorspaces[] = {
>> >> > +	/* For Default case, driver will set the colorspace */
>> >> > +	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
>> >> > +	/* Standard Definition Colorimetry based on CEA 861 */
>> >> > +	{ DRM_MODE_COLORIMETRY_ITU_601, "ITU_601" },
>> >>
>> >> The spec no longer has the BT.601 note here. Which I guess makes
>> >> sense since BT.601 didn't even specify any color primaries
>> >> initially. Later versions do by they have distinct primaries for
>> >> NTSC vs. PAL. The spec calls this just SMPTE 170M now, so I think we should
>do the same.
>>
>> Ok Sure, Will update this name. Yeah this was a little confusing as to
>> what name to go with. Will take the one defined now in spec i.e., SMPTE 170M.
>>
>> >>
>> >> > +	{ DRM_MODE_COLORIMETRY_ITU_709, "ITU_709" },
>> >> > +	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
>> >> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_601, "XV_YCC_601" },
>> >> > +	/* High Definition Colorimetry based on IEC 61966-2-4 */
>> >> > +	{ DRM_MODE_COLORIMETRY_XV_YCC_709, "XV_YCC_709" },
>> >> > +	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
>> >> > +	{ DRM_MODE_COLORIMETRY_S_YCC_601, "S_YCC_601" },
>> >> > +	/* Colorimetry based on IEC 61966-2-5 [33] */
>> >> > +	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
>> >>
>> >> The spelling is rather inconsistent here. XV_ vs. S_ vs. op. Why
>> >> not use the same spelling style for all?
>>
>> This is the names defined in spec and I used as is. I will make them
>> as XVYCC, SYCC and OPYCC for consistency. Hope this is ok ?
>>
>> >>
>> >> > +	/* Colorimetry based on IEC 61966-2-5 */
>> >> > +	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
>> >> > +	/* Colorimetry based on ITU-R BT.2020 */
>> >> > +	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
>> >> > +	/* Colorimetry based on ITU-R BT.2020 */
>> >> > +	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
>> >> > +	/* Colorimetry based on ITU-R BT.2020 */
>> >> > +	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
>> >>
>> >> "BT2020" vs. "ITU_709" is rather inconsistent as well.
>>
>> Ok, will update this.
>>
>> >> We also seem to be missing the two DCI-P3 things here.
>>
>> Yeah, I initially did as per 861.F where it was not there. This got
>> added in 861.G, will  add this.
>>
>> >> > +};
>> >> > +
>> >> >  /**
>> >> >   * DOC: standard connector properties
>> >> >   *
>> >> > @@ -1548,6 +1572,57 @@ int
>> >> > drm_mode_create_aspect_ratio_property(struct drm_device *dev)
>> >> > EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
>> >> >
>> >> >  /**
>> >> > + * DOC: standard connector properties
>> >> > + *
>> >> > + * Colorspace:
>> >> > + *     drm_mode_create_colorspace_property - create colorspace
>property
>> >> > + *     This property helps select a suitable colorspace based on the sink
>> >> > + *     capability. Modern sink devices support wider gamut like BT2020.
>> >> > + *     This helps switch to BT2020 mode if the BT2020 encoded video
>stream
>> >> > + *     is being played by the user, same for any other colorspace. Thereby
>> >> > + *     giving a good visual experience to users.
>> >> > + *
>> >> > + *     The expectation from userspace is that it should parse the EDID
>> >> > + *     and get supported colorspaces. Use this property and switch to the
>> >> > + *     one supported. Sink supported colorspaces should be retrieved by
>> >> > + *     userspace from EDID and driver will not explicitly expose them.
>> >> > + *
>> >> > + *     Basically the expectation from userspace is:
>> >> > + *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
>> >> > + *        colorspace
>> >> > + *      - Set this new property to let the sink know what it
>> >> > + *        converted the CRTC output to.
>> >> > + *      - This property is just to inform sink what colorspace
>> >> > + *        source is trying to drive.
>> >> > + *
>> >> > + * Called by a driver the first time it's needed, must be
>> >> > +attached to desired
>> >> > + * connectors.
>> >> > + */
>> >> > +int drm_mode_create_colorspace_property(struct drm_connector
>> >> > +*connector) {
>> >> > +	struct drm_device *dev = connector->dev;
>> >> > +	struct drm_property *prop;
>> >> > +
>> >> > +	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
>> >> > +	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
>> >> > +		prop = drm_property_create_enum(dev,
>> >DRM_MODE_PROP_ENUM,
>> >> > +						"Colorspace",
>> >> > +						hdmi_colorspaces,
>> >> > +
>> >	ARRAY_SIZE(hdmi_colorspaces));
>> >> > +		if (!prop)
>> >> > +			return -ENOMEM;
>> >> > +	} else {
>> >> > +		DRM_DEBUG_KMS("Colorspace property not supported\n");
>> >> > +		return 0;
>> >> > +	}
>> >> > +
>> >> > +	connector->colorspace_property = prop;
>> >> > +
>> >> > +	return 0;
>> >> > +}
>> >> > +EXPORT_SYMBOL(drm_mode_create_colorspace_property);
>> >> > +
>> >> > +/**
>> >> >   * drm_mode_create_content_type_property - create content type
>property
>> >> >   * @dev: DRM device
>> >> >   *
>> >> > diff --git a/include/drm/drm_connector.h
>> >> > b/include/drm/drm_connector.h index 9941613..29495b3 100644
>> >> > --- a/include/drm/drm_connector.h
>> >> > +++ b/include/drm/drm_connector.h
>> >> > @@ -253,6 +253,38 @@ enum drm_panel_orientation {
>> >> >  	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
>> >> >  };
>> >> >
>> >> > +/*
>> >> > + * This is a consolidated colorimetry list supported by HDMI and
>> >> > + * DP protocol standard. The respective connectors will register
>> >> > + * a property with the subset of this list (supported by that
>> >> > + * respective protocol). Userspace will set the colorspace
>> >> > +through
>> >> > + * a colorspace property which will be created and exposed to
>> >> > + * userspace.
>> >> > + */
>> >> > +
>> >> > +/* For Default case, driver will set the colorspace */
>> >> > +#define DRM_MODE_COLORIMETRY_DEFAULT			0
>> >> > +/* CEA 861 Normal Colorimetry options */
>> >> > +#define DRM_MODE_COLORIMETRY_ITU_601			1
>> >> > +#define DRM_MODE_COLORIMETRY_ITU_709			2
>> >> > +/* CEA 861 Extended Colorimetry Options */
>> >> > +#define DRM_MODE_COLORIMETRY_XV_YCC_601
>	3
>> >> > +#define DRM_MODE_COLORIMETRY_XV_YCC_709
>	4
>> >> > +#define DRM_MODE_COLORIMETRY_S_YCC_601			5
>> >> > +#define DRM_MODE_COLORIMETRY_OPYCC_601
>	6
>> >> > +#define DRM_MODE_COLORIMETRY_OPRGB			7
>> >> > +#define DRM_MODE_COLORIMETRY_BT2020_RGB
>	8
>> >> > +#define DRM_MODE_COLORIMETRY_BT2020_YCC
>	9
>> >> > +#define DRM_MODE_COLORIMETRY_BT2020_CYCC		10
>> >> > +/* DP MSA Colorimetry Options */
>> >> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_601
>	11
>> >> > +#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_709
>	12
>> >> > +#define DRM_MODE_DP_COLORIMETRY_SRGB			13
>> >> > +#define DRM_MODE_DP_COLORIMETRY_RGB_WIDE_GAMUT
>> >	14
>> >> > +#define DRM_MODE_DP_COLORIMETRY_SCRGB			15
>> >> > +#define DRM_MODE_DP_COLORIMETRY_DCI_P3			16
>> >> > +#define DRM_MODE_DP_COLORIMETRY_CUSTOM_COLOR_PROFILE
>> >	17
>> >>
>> >> I think some kind of macro to define these would be good. Assuming
>> >> we're trying directly interpret these as the C/EC/ACE bits. I can't
>> >> remember if multiple enum values can have the same integer value.
>> >> If not we'd also need a YCbCr vs. RGB bit in there somewhere.
>> >> Assuming we want to keep RGB and YCbCr separate. Currently only
>> >> BT.2020 has a conflict between the two.
>> >
>> >So I think I'm leaning towards having separate YCbCr vs. RGB values
>> >(which is what you had here already, with BT.2020 being the only case
>> >where that actually matters). That way someone could even do YCbCr
>> >4:4:4 passthrough by just stuffing YUV data into their RGB
>> >framebuffer (with the components swizzled the right way).
>> >
>> >The one thing that rather breaks that usecase is the automagic 4k
>> >YCbCr 4:2:0 fallback. So in in order to guarantee that things work
>> >correctly I guess we still need explcit control over the output CSC.
>> >
>> >Ie. some kind of output color encoding prop like this:
>> >	default /* current behaviour */
>> >	ycbcr BT.601
>> >	ycbcr BT.709
>> >	ycbcr BT.2020
>> >	/* no ycbcr 4:2:0 fallback for below modes? */
>> >	rgb 4:4:4
>> >	ycbcr 4:4:4 BT.601
>> >	ycbcr 4:4:4 BT.709
>> >	ycbcr 4:4:4 BT.2020
>> >	ycbcr 4:2:2 BT.601
>> >	ycbcr 4:2:2 BT.709
>> >	ycbcr 4:2:2 BT.2020
>> >	ycbcr 4:2:0 BT.601
>> >	ycbcr 4:2:0 BT.709
>> >	ycbcr 4:2:0 BT.2020
>> >
>> >Hmm. In fact the automagic 4:2:0 fallback sort of breaks the
>> >colorspace prop alredy because if someone set an RGB colorspace but
>> >we end up converting to YCbCr 4:2:0 what should we tell the sink?
>> >Maybe we just reject the modeset in that case and tell users they
>> >need to wait for the output color encoding prop to support that usecase?
>>
>> Hi yes, an output encoding property to control this make sense and will be
>useful.
>> So if a user decides to have a RGB buffer at source or wants to blend
>> multiple layers in RGB, and still want o/p converted to YUV420 at o/p,
>> he can use the current colorspace property to set that and send to
>> sink. In case he doesn't do it explicitly we can still let the content be driven but
>with warnings or choose to fail his modeset if that seems better.
>>
>> What do you suggest, should we keep current property interface like
>> this and extend the usage with a separate property on top of it.
>
>I think separate prop to control the output CSC is best. The colorspace prop
>should only control the infoframe. If the two are in violent disagreement we can
>fail the modeset.

Ok Sure, Will take that as a separate task to add a property interface for output CSC.
Thanks Ville !!!

>>
>> Thanks Ville for your review comments and suggestions.
>>
>> Regards,
>> Uma Shankar
>>
>> >
>> >>
>> >> > +
>> >> >  /**
>> >> >   * struct drm_display_info - runtime data about the connected sink
>> >> >   *
>> >> > @@ -503,6 +535,13 @@ struct drm_connector_state {
>> >> >  	unsigned int content_protection;
>> >> >
>> >> >  	/**
>> >> > +	 * @colorspace: State variable for Connector property to request
>> >> > +	 * colorspace change on Sink. This is most commonly used to switch
>> >> > +	 * to wider color gamuts like BT2020.
>> >> > +	 */
>> >> > +	u32 colorspace;
>> >> > +
>> >> > +	/**
>> >> >  	 * @writeback_job: Writeback job for writeback connectors
>> >> >  	 *
>> >> >  	 * Holds the framebuffer and out-fence for a writeback connector.
>> >> > As @@ -995,6 +1034,12 @@ struct drm_connector {
>> >> >  	struct drm_property *content_protection_property;
>> >> >
>> >> >  	/**
>> >> > +	 * @colorspace_property: Connector property to set the suitable
>> >> > +	 * colorspace supported by the sink.
>> >> > +	 */
>> >> > +	struct drm_property *colorspace_property;
>> >> > +
>> >> > +	/**
>> >> >  	 * @path_blob_ptr:
>> >> >  	 *
>> >> >  	 * DRM blob property data for the DP MST path property. This
>> >> > should only @@ -1269,6 +1314,7 @@ int
>> >> > drm_connector_attach_vrr_capable_property(
>> >> >  int drm_connector_attach_content_protection_property(
>> >> >  		struct drm_connector *connector);  int
>> >> > drm_mode_create_aspect_ratio_property(struct drm_device *dev);
>> >> > +int drm_mode_create_colorspace_property(struct drm_connector
>> >> > +*connector);
>> >> >  int drm_mode_create_content_type_property(struct drm_device
>> >> > *dev); void drm_hdmi_avi_infoframe_content_type(struct
>> >> > hdmi_avi_infoframe
>> >*frame,
>> >> >  					 const struct drm_connector_state
>> >*conn_state);
>> >> > --
>> >> > 1.9.1
>> >> >
>> >> > _______________________________________________
>> >> > Intel-gfx mailing list
>> >> > Intel-gfx@lists.freedesktop.org
>> >> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> >>
>> >> --
>> >> Ville Syrjälä
>> >> Intel
>> >> _______________________________________________
>> >> Intel-gfx mailing list
>> >> Intel-gfx@lists.freedesktop.org
>> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
>> >
>> >--
>> >Ville Syrjälä
>> >Intel
>
>--
>Ville Syrjälä
>Intel
>_______________________________________________
>dri-devel mailing list
>dri-devel@lists.freedesktop.org
>https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index 9a1f41a..9b5d44f 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -746,6 +746,8 @@  static int drm_atomic_connector_set_property(struct drm_connector *connector,
 			return -EINVAL;
 		}
 		state->content_protection = val;
+	} else if (property == connector->colorspace_property) {
+		state->colorspace = val;
 	} else if (property == config->writeback_fb_id_property) {
 		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, NULL, val);
 		int ret = drm_atomic_set_writeback_fb_for_connector(state, fb);
@@ -814,6 +816,8 @@  static int drm_atomic_connector_set_property(struct drm_connector *connector,
 		*val = state->picture_aspect_ratio;
 	} else if (property == config->content_type_property) {
 		*val = state->content_type;
+	} else if (property == connector->colorspace_property) {
+		*val = state->colorspace;
 	} else if (property == connector->scaling_mode_property) {
 		*val = state->scaling_mode;
 	} else if (property == connector->content_protection_property) {
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 8475396..ed10dd9 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -826,6 +826,30 @@  int drm_display_info_set_bus_formats(struct drm_display_info *info,
 };
 DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
 
+static const struct drm_prop_enum_list hdmi_colorspaces[] = {
+	/* For Default case, driver will set the colorspace */
+	{ DRM_MODE_COLORIMETRY_DEFAULT, "Default" },
+	/* Standard Definition Colorimetry based on CEA 861 */
+	{ DRM_MODE_COLORIMETRY_ITU_601, "ITU_601" },
+	{ DRM_MODE_COLORIMETRY_ITU_709, "ITU_709" },
+	/* Standard Definition Colorimetry based on IEC 61966-2-4 */
+	{ DRM_MODE_COLORIMETRY_XV_YCC_601, "XV_YCC_601" },
+	/* High Definition Colorimetry based on IEC 61966-2-4 */
+	{ DRM_MODE_COLORIMETRY_XV_YCC_709, "XV_YCC_709" },
+	/* Colorimetry based on IEC 61966-2-1/Amendment 1 */
+	{ DRM_MODE_COLORIMETRY_S_YCC_601, "S_YCC_601" },
+	/* Colorimetry based on IEC 61966-2-5 [33] */
+	{ DRM_MODE_COLORIMETRY_OPYCC_601, "opYCC_601" },
+	/* Colorimetry based on IEC 61966-2-5 */
+	{ DRM_MODE_COLORIMETRY_OPRGB, "opRGB" },
+	/* Colorimetry based on ITU-R BT.2020 */
+	{ DRM_MODE_COLORIMETRY_BT2020_RGB, "BT2020_RGB" },
+	/* Colorimetry based on ITU-R BT.2020 */
+	{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
+	/* Colorimetry based on ITU-R BT.2020 */
+	{ DRM_MODE_COLORIMETRY_BT2020_CYCC, "BT2020_CYCC" },
+};
+
 /**
  * DOC: standard connector properties
  *
@@ -1548,6 +1572,57 @@  int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
 EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);
 
 /**
+ * DOC: standard connector properties
+ *
+ * Colorspace:
+ *     drm_mode_create_colorspace_property - create colorspace property
+ *     This property helps select a suitable colorspace based on the sink
+ *     capability. Modern sink devices support wider gamut like BT2020.
+ *     This helps switch to BT2020 mode if the BT2020 encoded video stream
+ *     is being played by the user, same for any other colorspace. Thereby
+ *     giving a good visual experience to users.
+ *
+ *     The expectation from userspace is that it should parse the EDID
+ *     and get supported colorspaces. Use this property and switch to the
+ *     one supported. Sink supported colorspaces should be retrieved by
+ *     userspace from EDID and driver will not explicitly expose them.
+ *
+ *     Basically the expectation from userspace is:
+ *      - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
+ *        colorspace
+ *      - Set this new property to let the sink know what it
+ *        converted the CRTC output to.
+ *      - This property is just to inform sink what colorspace
+ *        source is trying to drive.
+ *
+ * Called by a driver the first time it's needed, must be attached to desired
+ * connectors.
+ */
+int drm_mode_create_colorspace_property(struct drm_connector *connector)
+{
+	struct drm_device *dev = connector->dev;
+	struct drm_property *prop;
+
+	if (connector->connector_type == DRM_MODE_CONNECTOR_HDMIA ||
+	    connector->connector_type == DRM_MODE_CONNECTOR_HDMIB) {
+		prop = drm_property_create_enum(dev, DRM_MODE_PROP_ENUM,
+						"Colorspace",
+						hdmi_colorspaces,
+						ARRAY_SIZE(hdmi_colorspaces));
+		if (!prop)
+			return -ENOMEM;
+	} else {
+		DRM_DEBUG_KMS("Colorspace property not supported\n");
+		return 0;
+	}
+
+	connector->colorspace_property = prop;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_mode_create_colorspace_property);
+
+/**
  * drm_mode_create_content_type_property - create content type property
  * @dev: DRM device
  *
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 9941613..29495b3 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -253,6 +253,38 @@  enum drm_panel_orientation {
 	DRM_MODE_PANEL_ORIENTATION_RIGHT_UP,
 };
 
+/*
+ * This is a consolidated colorimetry list supported by HDMI and
+ * DP protocol standard. The respective connectors will register
+ * a property with the subset of this list (supported by that
+ * respective protocol). Userspace will set the colorspace through
+ * a colorspace property which will be created and exposed to
+ * userspace.
+ */
+
+/* For Default case, driver will set the colorspace */
+#define DRM_MODE_COLORIMETRY_DEFAULT			0
+/* CEA 861 Normal Colorimetry options */
+#define DRM_MODE_COLORIMETRY_ITU_601			1
+#define DRM_MODE_COLORIMETRY_ITU_709			2
+/* CEA 861 Extended Colorimetry Options */
+#define DRM_MODE_COLORIMETRY_XV_YCC_601			3
+#define DRM_MODE_COLORIMETRY_XV_YCC_709			4
+#define DRM_MODE_COLORIMETRY_S_YCC_601			5
+#define DRM_MODE_COLORIMETRY_OPYCC_601			6
+#define DRM_MODE_COLORIMETRY_OPRGB			7
+#define DRM_MODE_COLORIMETRY_BT2020_RGB			8
+#define DRM_MODE_COLORIMETRY_BT2020_YCC			9
+#define DRM_MODE_COLORIMETRY_BT2020_CYCC		10
+/* DP MSA Colorimetry Options */
+#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_601		11
+#define DRM_MODE_DP_COLORIMETRY_Y_CBCR_ITU_709		12
+#define DRM_MODE_DP_COLORIMETRY_SRGB			13
+#define DRM_MODE_DP_COLORIMETRY_RGB_WIDE_GAMUT		14
+#define DRM_MODE_DP_COLORIMETRY_SCRGB			15
+#define DRM_MODE_DP_COLORIMETRY_DCI_P3			16
+#define DRM_MODE_DP_COLORIMETRY_CUSTOM_COLOR_PROFILE	17
+
 /**
  * struct drm_display_info - runtime data about the connected sink
  *
@@ -503,6 +535,13 @@  struct drm_connector_state {
 	unsigned int content_protection;
 
 	/**
+	 * @colorspace: State variable for Connector property to request
+	 * colorspace change on Sink. This is most commonly used to switch
+	 * to wider color gamuts like BT2020.
+	 */
+	u32 colorspace;
+
+	/**
 	 * @writeback_job: Writeback job for writeback connectors
 	 *
 	 * Holds the framebuffer and out-fence for a writeback connector. As
@@ -995,6 +1034,12 @@  struct drm_connector {
 	struct drm_property *content_protection_property;
 
 	/**
+	 * @colorspace_property: Connector property to set the suitable
+	 * colorspace supported by the sink.
+	 */
+	struct drm_property *colorspace_property;
+
+	/**
 	 * @path_blob_ptr:
 	 *
 	 * DRM blob property data for the DP MST path property. This should only
@@ -1269,6 +1314,7 @@  int drm_connector_attach_vrr_capable_property(
 int drm_connector_attach_content_protection_property(
 		struct drm_connector *connector);
 int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
+int drm_mode_create_colorspace_property(struct drm_connector *connector);
 int drm_mode_create_content_type_property(struct drm_device *dev);
 void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame,
 					 const struct drm_connector_state *conn_state);