drm/i915: Merge ironlake_compute_clocks() and ironlake_crtc_compute_clock()

Merge ironlake_compute_clocks() into ironlake_crtc_compute_clock() so
the clock computation logic is all in one place. The resulting function
is still quite simple. Follow up patches will make the similar code for
GMCH platforms look similar.

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458576016-30348-12-git-send-email-ander.conselvan.de.oliveira@intel.com

drivers/gpu/drm/i915/intel_display.c

@@ -846,6 +846,11 @@ pnv_find_best_dpll(const intel_limit_t *limit,
 	return (err != target);
 }
 
+/*
+ * Returns a set of divisors for the desired target clock with the given
+ * refclk, or FALSE.  The returned values represent the clock equation:
+ * reflck * (5 * (m1 + 2) + (m2 + 2)) / (n + 2) / p1 / p2.
+ */
 static bool
 g4x_find_best_dpll(const intel_limit_t *limit,
 		   struct intel_crtc_state *crtc_state,
@@ -8628,55 +8633,6 @@ static void haswell_set_pipemisc(struct drm_crtc *crtc)
 	}
 }
 
-static bool ironlake_compute_clocks(struct drm_crtc *crtc,
-				    struct intel_crtc_state *crtc_state,
-				    intel_clock_t *clock,
-				    bool *has_reduced_clock,
-				    intel_clock_t *reduced_clock)
-{
-	struct drm_device *dev = crtc->dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
-	int refclk;
-	const intel_limit_t *limit;
-	bool ret;
-
-	refclk = 120000;
-
-	if (intel_pipe_will_have_type(crtc_state, INTEL_OUTPUT_LVDS)) {
-		if (intel_panel_use_ssc(dev_priv)) {
-			DRM_DEBUG_KMS("using SSC reference clock of %d kHz\n",
-				      dev_priv->vbt.lvds_ssc_freq);
-			refclk = dev_priv->vbt.lvds_ssc_freq;
-		}
-
-		if (intel_is_dual_link_lvds(dev)) {
-			if (refclk == 100000)
-				limit = &intel_limits_ironlake_dual_lvds_100m;
-			else
-				limit = &intel_limits_ironlake_dual_lvds;
-		} else {
-			if (refclk == 100000)
-				limit = &intel_limits_ironlake_single_lvds_100m;
-			else
-				limit = &intel_limits_ironlake_single_lvds;
-		}
-	} else {
-		limit = &intel_limits_ironlake_dac;
-	}
-
-	/*
-	 * Returns a set of divisors for the desired target clock with the given
-	 * refclk, or FALSE.  The returned values represent the clock equation:
-	 * reflck * (5 * (m1 + 2) + (m2 + 2)) / (n + 2) / p1 / p2.
-	 */
-	ret = g4x_find_best_dpll(limit, crtc_state, crtc_state->port_clock,
-				 refclk, NULL, clock);
-	if (!ret)
-		return false;
-
-	return true;
-}
-
 int ironlake_get_lanes_required(int target_clock, int link_bw, int bpp)
 {
 	/*
@@ -8801,9 +8757,13 @@ static void ironlake_compute_dpll(struct intel_crtc *intel_crtc,
 static int ironlake_crtc_compute_clock(struct intel_crtc *crtc,
 				       struct intel_crtc_state *crtc_state)
 {
+	struct drm_device *dev = crtc->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	intel_clock_t reduced_clock;
 	bool has_reduced_clock = false;
 	struct intel_shared_dpll *pll;
+	const intel_limit_t *limit;
+	int refclk = 120000;
 
 	memset(&crtc_state->dpll_hw_state, 0,
 	       sizeof(crtc_state->dpll_hw_state));
@@ -8814,11 +8774,31 @@ static int ironlake_crtc_compute_clock(struct intel_crtc *crtc,
 	if (!crtc_state->has_pch_encoder)
 		return 0;
 
+	if (intel_pipe_will_have_type(crtc_state, INTEL_OUTPUT_LVDS)) {
+		if (intel_panel_use_ssc(dev_priv)) {
+			DRM_DEBUG_KMS("using SSC reference clock of %d kHz\n",
+				      dev_priv->vbt.lvds_ssc_freq);
+			refclk = dev_priv->vbt.lvds_ssc_freq;
+		}
+
+		if (intel_is_dual_link_lvds(dev)) {
+			if (refclk == 100000)
+				limit = &intel_limits_ironlake_dual_lvds_100m;
+			else
+				limit = &intel_limits_ironlake_dual_lvds;
+		} else {
+			if (refclk == 100000)
+				limit = &intel_limits_ironlake_single_lvds_100m;
+			else
+				limit = &intel_limits_ironlake_single_lvds;
+		}
+	} else {
+		limit = &intel_limits_ironlake_dac;
+	}
+
 	if (!crtc_state->clock_set &&
-	    !ironlake_compute_clocks(&crtc->base, crtc_state,
-				     &crtc_state->dpll,
-				     &has_reduced_clock,
-				     &reduced_clock)) {
+	    !g4x_find_best_dpll(limit, crtc_state, crtc_state->port_clock,
+				refclk, NULL, &crtc_state->dpll)) {
 		DRM_ERROR("Couldn't find PLL settings for mode!\n");
 		return -EINVAL;
 	}