drm/i915: Fix skl+ non-scaled pfit modes

Fix skl_update_scaler_crtc() to deal with different scaling
modes correctly. The current implementation assumes
DRM_MODE_SCALE_FULLSCREEN. Fortunately we don't expose any
border properties currently so the code does actually end
up doing the right thing (assigning a scaler for pfit).
The code does need to be fixed before any borders are
exposed.

Also we have redundant calls to skl_update_scaler_crtc() in
dp/hdmi .compute_config() which can be nuked. They were anyway
called before we had even computed the pfit state so were
basically nonsense. The real call we need to keep is in
intel_crtc_atomic_check().

v2: Deal witrh skl_update_scaler_crtc() in intel_dp_ycbcr420_config()
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200422161917.17389-1-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/display/intel_display.c

@@ -6089,30 +6089,28 @@ skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach,
 	return 0;
 }
 
-/**
- * skl_update_scaler_crtc - Stages update to scaler state for a given crtc.
- *
- * @state: crtc's scaler state
- *
- * Return
- *     0 - scaler_usage updated successfully
- *    error - requested scaling cannot be supported or other error condition
- */
-int skl_update_scaler_crtc(struct intel_crtc_state *state)
+static int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state)
 {
-	const struct drm_display_mode *adjusted_mode = &state->hw.adjusted_mode;
-	bool need_scaler = false;
+	const struct drm_display_mode *adjusted_mode =
+		&crtc_state->hw.adjusted_mode;
+	int width, height;
 
-	if (state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 ||
-	    state->pch_pfit.enabled)
-		need_scaler = true;
+	if (crtc_state->pch_pfit.enabled) {
+		u32 pfit_size = crtc_state->pch_pfit.size;
+
+		width = pfit_size >> 16;
+		height = pfit_size & 0xffff;
+	} else {
+		width = adjusted_mode->crtc_hdisplay;
+		height = adjusted_mode->crtc_vdisplay;
+	}
 
-	return skl_update_scaler(state, !state->hw.active, SKL_CRTC_INDEX,
-				 &state->scaler_state.scaler_id,
-				 state->pipe_src_w, state->pipe_src_h,
-				 adjusted_mode->crtc_hdisplay,
-				 adjusted_mode->crtc_vdisplay, NULL, 0,
-				 need_scaler);
+	return skl_update_scaler(crtc_state, !crtc_state->hw.active,
+				 SKL_CRTC_INDEX,
+				 &crtc_state->scaler_state.scaler_id,
+				 crtc_state->pipe_src_w, crtc_state->pipe_src_h,
+				 width, height, NULL, 0,
+				 crtc_state->pch_pfit.enabled);
 }
 
 /**

drivers/gpu/drm/i915/display/intel_display.h

@@ -591,7 +591,6 @@ void intel_crtc_arm_fifo_underrun(struct intel_crtc *crtc,
 				  struct intel_crtc_state *crtc_state);
 
 u16 skl_scaler_calc_phase(int sub, int scale, bool chroma_center);
-int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state);
 void skl_scaler_disable(const struct intel_crtc_state *old_crtc_state);
 void ilk_pfit_disable(const struct intel_crtc_state *old_crtc_state);
 u32 glk_plane_color_ctl(const struct intel_crtc_state *crtc_state,

drivers/gpu/drm/i915/display/intel_dp.c

@@ -2342,12 +2342,10 @@ intel_dp_ycbcr420_config(struct intel_dp *intel_dp,
 			 struct drm_connector *connector,
 			 struct intel_crtc_state *crtc_state)
 {
-	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 	const struct drm_display_info *info = &connector->display_info;
 	const struct drm_display_mode *adjusted_mode =
 		&crtc_state->hw.adjusted_mode;
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
-	int ret;
 
 	if (!drm_mode_is_420_only(info, adjusted_mode) ||
 	    !intel_dp_get_colorimetry_status(intel_dp) ||
@@ -2356,14 +2354,6 @@ intel_dp_ycbcr420_config(struct intel_dp *intel_dp,
 
 	crtc_state->output_format = INTEL_OUTPUT_FORMAT_YCBCR420;
 
-	/* YCBCR 420 output conversion needs a scaler */
-	ret = skl_update_scaler_crtc(crtc_state);
-	if (ret) {
-		drm_dbg_kms(&i915->drm,
-			    "Scaler allocation for output failed\n");
-		return ret;
-	}
-
 	intel_pch_panel_fitting(crtc, crtc_state, DRM_MODE_SCALE_FULLSCREEN);
 
 	return 0;
@@ -2563,7 +2553,6 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 	else
 		ret = intel_dp_ycbcr420_config(intel_dp, &intel_connector->base,
 					       pipe_config);
-
 	if (ret)
 		return ret;
 
@@ -2579,12 +2568,6 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 		intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
 				       adjusted_mode);
 
-		if (INTEL_GEN(dev_priv) >= 9) {
-			ret = skl_update_scaler_crtc(pipe_config);
-			if (ret)
-				return ret;
-		}
-
 		if (HAS_GMCH(dev_priv))
 			intel_gmch_panel_fitting(intel_crtc, pipe_config,
 						 conn_state->scaling_mode);

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -2336,13 +2336,6 @@ intel_hdmi_ycbcr420_config(struct drm_connector *connector,
 
 	config->output_format = INTEL_OUTPUT_FORMAT_YCBCR420;
 
-	/* YCBCR 420 output conversion needs a scaler */
-	if (skl_update_scaler_crtc(config)) {
-		drm_dbg_kms(&i915->drm,
-			    "Scaler allocation for output failed\n");
-		return false;
-	}
-
 	intel_pch_panel_fitting(intel_crtc, config,
 				DRM_MODE_SCALE_FULLSCREEN);