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.

...

• { 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

---

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-- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx