[Intel-gfx] [PATCH v3] drm/i915: Add Plane color encoding support for YCBCR_BT2020

[Ville Syrjälä]

On Wed, Apr 08, 2020 at 01:23:27PM +0000, Shankar, Uma wrote:
> 
> 
> > -----Original Message-----
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Sent: Wednesday, April 8, 2020 6:17 PM
> > To: Kadiyala, Kishore <kishore.kadiyala at intel.com>
> > Cc: intel-gfx at lists.freedesktop.org; Shankar, Uma <uma.shankar at intel.com>;
> > Nikula, Jani <jani.nikula at intel.com>
> > Subject: Re: [PATCH v3] drm/i915: Add Plane color encoding support for
> > YCBCR_BT2020
> > 
> > On Wed, Apr 08, 2020 at 04:43:47PM +0530, Kishore Kadiyala wrote:
> > > Currently the plane property doesn't have support for YCBCR_BT2020,
> > > which enables the corresponding color conversion mode on plane CSC.
> > > In ICL+ platforms , this property setting is confined only to HDR
> > > Planes as there is limitation in SDR Planes and while in GLK it set
> > > for all planes.
> > >
> > > V2: Enabling support for YCBCT_BT2020 for HDR planes on
> > >     platforms GLK & ICL
> > >
> > > V3: Refined the condition check to handle GLK & ICL+ HDR planes
> > >     Also added BT2020 handling in glk_plane_color_ctl.
> > >
> > > Cc: Ville Syrjala <ville.syrjala at linux.intel.com>
> > > Cc: Uma Shankar <uma.shankar at intel.com>
> > > Cc: Jani Nikula <jani.nikula at intel.com>
> > > Signed-off-by: Kishore Kadiyala <kishore.kadiyala at intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_display.c | 12 +++++++++---
> > > drivers/gpu/drm/i915/display/intel_sprite.c  | 17 +++++++++++++++--
> > >  2 files changed, 24 insertions(+), 5 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> > > b/drivers/gpu/drm/i915/display/intel_display.c
> > > index 70ec301fe6e3..f2dfa61a49fa 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > > @@ -4808,11 +4808,17 @@ u32 glk_plane_color_ctl(const struct intel_crtc_state
> > *crtc_state,
> > >  	plane_color_ctl |= glk_plane_color_ctl_alpha(plane_state);
> > >
> > >  	if (fb->format->is_yuv && !icl_is_hdr_plane(dev_priv, plane->id)) {
> > > -		if (plane_state->hw.color_encoding ==
> > DRM_COLOR_YCBCR_BT709)
> > > +		switch (plane_state->hw.color_encoding) {
> > > +		case DRM_COLOR_YCBCR_BT709:
> > >  			plane_color_ctl |=
> > PLANE_COLOR_CSC_MODE_YUV709_TO_RGB709;
> > > -		else
> > > +			break;
> > > +		case DRM_COLOR_YCBCR_BT2020:
> > > +			plane_color_ctl |=
> > > +
> > 	PLANE_COLOR_CSC_MODE_YUV2020_TO_RGB2020;
> > > +			break;
> > > +		default:
> > >  			plane_color_ctl |=
> > PLANE_COLOR_CSC_MODE_YUV601_TO_RGB709;
> > > -
> > > +		}
> > >  		if (plane_state->hw.color_range ==
> > DRM_COLOR_YCBCR_FULL_RANGE)
> > >  			plane_color_ctl |=
> > PLANE_COLOR_YUV_RANGE_CORRECTION_DISABLE;
> > >  	} else if (fb->format->is_yuv) {
> > > diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c
> > > b/drivers/gpu/drm/i915/display/intel_sprite.c
> > > index deda351719db..237c4b951f02 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_sprite.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_sprite.c
> > > @@ -3031,6 +3031,7 @@ skl_universal_plane_create(struct drm_i915_private
> > *dev_priv,
> > >  	struct intel_plane *plane;
> > >  	enum drm_plane_type plane_type;
> > >  	unsigned int supported_rotations;
> > > +	unsigned int supported_csc;
> > >  	const u64 *modifiers;
> > >  	const u32 *formats;
> > >  	int num_formats;
> > > @@ -3105,9 +3106,21 @@ skl_universal_plane_create(struct drm_i915_private
> > *dev_priv,
> > >  					   DRM_MODE_ROTATE_0,
> > >  					   supported_rotations);
> > >
> > > +	supported_csc = BIT(DRM_COLOR_YCBCR_BT601) |
> > > +BIT(DRM_COLOR_YCBCR_BT709);
> > > +
> > > +	/*
> > > +	 * Setting the CSC BT2020 for all the planes in case of GLK
> > > +	 * While for ICL+ platforms it is set only for HDR planes 1 through 3
> > > +	 * as there are issues seen with SDR planes
> > 
> > What issues are those?
> 
> There was an issue on some of the hardcoded matrix values used in SDR planes,
> hence it would be good to not enable BT2020 conversion on SDR planes in ICL+
> till this gets resolved. 
> Reference WA: #220884772
> "Incorrect plane CSC coefficients for sRGB to Bt2020 :
> SDR planes PLANE_COLOR_CTL Plane CSC Mode 100b, RGB709 to RGB2020, 
> uses hardcoded R-Y coefficient of 0.75 instead of 0.625, resulting in incorrect BT2020
> color conversion. WA: Limit RGB709 to RGB2020 conversion to the HDR capable planes"

That only matters for RGB->RGB conversion, which has nothing to do with
this patch.

> 
> @Kishore : Please add this as comment here.
> 
> > > +	 */
> > > +	if ((INTEL_GEN(dev_priv) == 10) ||  IS_GEMINILAKE(dev_priv))
> > > +		supported_csc |= BIT(DRM_COLOR_YCBCR_BT2020);
> > > +	else
> > > +		if (icl_is_hdr_plane(dev_priv, plane_id))
> > > +			supported_csc |= BIT(DRM_COLOR_YCBCR_BT2020);
> > > +
> > >  	drm_plane_create_color_properties(&plane->base,
> > > -					  BIT(DRM_COLOR_YCBCR_BT601) |
> > > -					  BIT(DRM_COLOR_YCBCR_BT709),
> > > +					  supported_csc,
> > >
> > BIT(DRM_COLOR_YCBCR_LIMITED_RANGE) |
> > >  					  BIT(DRM_COLOR_YCBCR_FULL_RANGE),
> > >  					  DRM_COLOR_YCBCR_BT709,
> > > --
> > > 2.17.1
> > 
> > --
> > Ville Syrjälä
> > Intel

-- 
Ville Syrjälä
Intel