drm/i915: Extract ilk_csc_limited_range()

Extract a helper which determines if we need to use the
pipe CSC for limited range RGB output.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190218193137.22914-4-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>

drivers/gpu/drm/i915/intel_color.c

@@ -161,22 +161,28 @@ static void ilk_load_ycbcr_conversion_matrix(struct intel_crtc *crtc)
 	}
 }
 
+static bool ilk_csc_limited_range(const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);
+
+	/*
+	 * FIXME if there's a gamma LUT after the CSC, we should
+	 * do the range compression using the gamma LUT instead.
+	 */
+	return crtc_state->limited_color_range &&
+		(IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv) ||
+		 IS_GEN_RANGE(dev_priv, 9, 10));
+}
+
 static void ilk_load_csc_matrix(const struct intel_crtc_state *crtc_state)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
-	bool limited_color_range = false;
+	bool limited_color_range = ilk_csc_limited_range(crtc_state);
 	enum pipe pipe = crtc->pipe;
 	u16 coeffs[9] = {};
 	int i;
 
-	/*
-	 * FIXME if there's a gamma LUT after the CSC, we should
-	 * do the range compression using the gamma LUT instead.
-	 */
-	if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv))
-		limited_color_range = crtc_state->limited_color_range;
-
 	if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR420 ||
 	    crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR444) {
 		ilk_load_ycbcr_conversion_matrix(crtc);