Re: [PATCH v2 7/9] drm/i915/dp: Replace intel_dp.dfp members with the new crtc_state dp_dfp members

["Nautiyal, Ankit K" <ankit.k.nautiyal@xxxxxxxxx>]

On 9/13/2022 12:26 AM, Ville Syrjälä wrote:
> On Thu, Sep 01, 2022 at 11:30:59AM +0530, Ankit Nautiyal wrote:
> > The decision to use DFP output format conversion capabilities should be
> > during compute_config phase.
> >
> > This patch uses the members of intel_dp->dfp to only store the
> > format conversion capabilities of the DP device and uses the crtc_state
> > dp_dfp members that are computed earlier, to program the
> > protocol-converter for colorspace/format conversion.
> >
> > Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@xxxxxxxxx>
> > ---
> >   drivers/gpu/drm/i915/display/intel_dp.c | 46 +++++++++----------------
> >   1 file changed, 17 insertions(+), 29 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
> > index f3c2aeda0c1d..409bd9cdf450 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> > @@ -805,6 +805,7 @@ intel_dp_output_format(struct intel_connector *connector,
> >   		       bool ycbcr_420_output)
> >   {
> >   	struct intel_dp *intel_dp = intel_attached_dp(connector);
> > +	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> >   
> >   	if (!connector->base.ycbcr_420_allowed || !ycbcr_420_output)
> >   		return INTEL_OUTPUT_FORMAT_RGB;
> > @@ -813,6 +814,10 @@ intel_dp_output_format(struct intel_connector *connector,
> >   	    intel_dp->dfp.ycbcr_444_to_420)
> >   		return INTEL_OUTPUT_FORMAT_RGB;
> >   
> > +	/* Prefer 4:2:0 passthrough over 4:4:4->4:2:0 conversion */
> > +	if (DISPLAY_VER(i915) >= 11 && intel_dp->dfp.ycbcr420_passthrough)
> > +		return INTEL_OUTPUT_FORMAT_YCBCR420;
> > +
> >   	if (intel_dp->dfp.ycbcr_444_to_420)
> >   		return INTEL_OUTPUT_FORMAT_YCBCR444;
> >   	else
> > @@ -2698,8 +2703,8 @@ void intel_dp_configure_protocol_converter(struct intel_dp *intel_dp,
> >   		drm_dbg_kms(&i915->drm, "Failed to %s protocol converter HDMI mode\n",
> >   			    str_enable_disable(intel_dp->has_hdmi_sink));
> >   
> > -	tmp = crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR444 &&
> > -		intel_dp->dfp.ycbcr_444_to_420 ? DP_CONVERSION_TO_YCBCR420_ENABLE : 0;
> > +	tmp = crtc_state->dp_dfp_config.ycbcr_444_to_420 ?
> > +		DP_CONVERSION_TO_YCBCR420_ENABLE : 0;
> >   
> >   	if (drm_dp_dpcd_writeb(&intel_dp->aux,
> >   			       DP_PROTOCOL_CONVERTER_CONTROL_1, tmp) != 1)
> > @@ -2707,7 +2712,7 @@ void intel_dp_configure_protocol_converter(struct intel_dp *intel_dp,
> >   			    "Failed to %s protocol converter YCbCr 4:2:0 conversion mode\n",
> >   			    str_enable_disable(intel_dp->dfp.ycbcr_444_to_420));
> >   
> > -	tmp = intel_dp->dfp.rgb_to_ycbcr ?
> > +	tmp = crtc_state->dp_dfp_config.rgb_to_ycbcr ?
> >   		DP_CONVERSION_BT709_RGB_YCBCR_ENABLE : 0;
> >   
> >   	if (drm_dp_pcon_convert_rgb_to_ycbcr(&intel_dp->aux, tmp) < 0)
> > @@ -4563,7 +4568,7 @@ intel_dp_update_420(struct intel_dp *intel_dp)
> >   {
> >   	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> >   	struct intel_connector *connector = intel_dp->attached_connector;
> > -	bool is_branch, ycbcr_420_passthrough, ycbcr_444_to_420, rgb_to_ycbcr;
> > +	bool is_branch;
> >   
> >   	/* No YCbCr output support on gmch platforms */
> >   	if (HAS_GMCH(i915))
> > @@ -4577,38 +4582,21 @@ intel_dp_update_420(struct intel_dp *intel_dp)
> >   		return;
> >   
> >   	is_branch = drm_dp_is_branch(intel_dp->dpcd);
> > -	ycbcr_420_passthrough =
> > +	intel_dp->dfp.ycbcr420_passthrough =
> >   		drm_dp_downstream_420_passthrough(intel_dp->dpcd,
> >   						  intel_dp->downstream_ports);
> >   	/* on-board LSPCON always assumed to support 4:4:4->4:2:0 conversion */
> > -	ycbcr_444_to_420 =
> > +	intel_dp->dfp.ycbcr_444_to_420 =
> >   		dp_to_dig_port(intel_dp)->lspcon.active ||
> >   		drm_dp_downstream_444_to_420_conversion(intel_dp->dpcd,
> >   							intel_dp->downstream_ports);
> > -	rgb_to_ycbcr = drm_dp_downstream_rgb_to_ycbcr_conversion(intel_dp->dpcd,
> > -								 intel_dp->downstream_ports,
> > -								 DP_DS_HDMI_BT709_RGB_YCBCR_CONV);
> > -
> > -	if (DISPLAY_VER(i915) >= 11) {
> > -		/* Let PCON convert from RGB->YCbCr if possible */
> > -		if (is_branch && rgb_to_ycbcr && ycbcr_444_to_420) {
> > -			intel_dp->dfp.rgb_to_ycbcr = true;
> > -			intel_dp->dfp.ycbcr_444_to_420 = true;
> > -			connector->base.ycbcr_420_allowed = true;
> > -		} else {
> > -		/* Prefer 4:2:0 passthrough over 4:4:4->4:2:0 conversion */
> > -			intel_dp->dfp.ycbcr_444_to_420 =
> > -				ycbcr_444_to_420 && !ycbcr_420_passthrough;
> > +	intel_dp->dfp.rgb_to_ycbcr =
> > +		drm_dp_downstream_rgb_to_ycbcr_conversion(intel_dp->dpcd,
> > +							  intel_dp->downstream_ports,
> > +							  DP_DS_HDMI_BT709_RGB_YCBCR_CONV);
> >   
> > -			connector->base.ycbcr_420_allowed =
> > -				!is_branch || ycbcr_444_to_420 || ycbcr_420_passthrough;
> > -		}
> > -	} else {
> > -		/* 4:4:4->4:2:0 conversion is the only way */
> > -		intel_dp->dfp.ycbcr_444_to_420 = ycbcr_444_to_420;
> > -
> > -		connector->base.ycbcr_420_allowed = ycbcr_444_to_420;
> > -	}
> > +	if (!is_branch || intel_dp->dfp.ycbcr420_passthrough || intel_dp->dfp.ycbcr_444_to_420)
> > +		connector->base.ycbcr_420_allowed = true;
> That part looks wrong for pre-icl now. They can't do the 4:2:0
> passthrough.


I have not put condition here, as here we are just storing the PCON 
conversion capability.

I have added the condition in intel_dp_output_format with ycbcr420passthrough for Display >= 11.

But yes for pre icl if dfp does not support 444_to_420, and since we cant do 4:2:0,
the connector->base.ycbcr420_allowed should perhaps be false.

I can add a condition for that.

Regards,
Ankit


> >   
> >   	drm_dbg_kms(&i915->drm,
> >   		    "[CONNECTOR:%d:%s] RGB->YcbCr conversion? %s, YCbCr 4:2:0 allowed? %s, YCbCr 4:4:4->4:2:0 conversion? %s\n",
> > --
> > 2.25.1