drm/i915: Pass computed vco to bxt_set_cdclk()

Rather than compute the vco inside bxt_set_cdclk() let's precompute it
outside and pass it in. A small step towards a fully precomputed cdclk
state.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170120182205.8141-7-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/intel_cdclk.c

@@ -1143,15 +1143,11 @@ static void bxt_de_pll_enable(struct drm_i915_private *dev_priv, int vco)
 	dev_priv->cdclk_pll.vco = vco;
 }
 
-static void bxt_set_cdclk(struct drm_i915_private *dev_priv, int cdclk)
+static void bxt_set_cdclk(struct drm_i915_private *dev_priv,
+			  int cdclk, int vco)
 {
 	u32 val, divider;
-	int vco, ret;
-
-	if (IS_GEMINILAKE(dev_priv))
-		vco = glk_de_pll_vco(dev_priv, cdclk);
-	else
-		vco = bxt_de_pll_vco(dev_priv, cdclk);
+	int ret;
 
 	DRM_DEBUG_DRIVER("Changing CDCLK to %d kHz (VCO %d kHz)\n",
 			 cdclk, vco);
@@ -1284,7 +1280,7 @@ static void bxt_sanitize_cdclk(struct drm_i915_private *dev_priv)
  */
 void bxt_init_cdclk(struct drm_i915_private *dev_priv)
 {
-	int cdclk;
+	int cdclk, vco;
 
 	bxt_sanitize_cdclk(dev_priv);
 
@@ -1296,12 +1292,15 @@ void bxt_init_cdclk(struct drm_i915_private *dev_priv)
 	 * - The initial CDCLK needs to be read from VBT.
 	 *   Need to make this change after VBT has changes for BXT.
 	 */
-	if (IS_GEMINILAKE(dev_priv))
+	if (IS_GEMINILAKE(dev_priv)) {
 		cdclk = glk_calc_cdclk(0);
-	else
+		vco = glk_de_pll_vco(dev_priv, cdclk);
+	} else {
 		cdclk = bxt_calc_cdclk(0);
+		vco = bxt_de_pll_vco(dev_priv, cdclk);
+	}
 
-	bxt_set_cdclk(dev_priv, cdclk);
+	bxt_set_cdclk(dev_priv, cdclk, vco);
 }
 
 /**
@@ -1313,7 +1312,7 @@ void bxt_init_cdclk(struct drm_i915_private *dev_priv)
  */
 void bxt_uninit_cdclk(struct drm_i915_private *dev_priv)
 {
-	bxt_set_cdclk(dev_priv, dev_priv->cdclk_pll.ref);
+	bxt_set_cdclk(dev_priv, dev_priv->cdclk_pll.ref, 0);
 }
 
 static int bdw_adjust_min_pipe_pixel_rate(struct intel_crtc_state *crtc_state,
@@ -1533,12 +1532,18 @@ static int bxt_modeset_calc_cdclk(struct drm_atomic_state *state)
 
 static void bxt_modeset_commit_cdclk(struct drm_atomic_state *old_state)
 {
-	struct drm_device *dev = old_state->dev;
+	struct drm_i915_private *dev_priv = to_i915(old_state->dev);
 	struct intel_atomic_state *old_intel_state =
 		to_intel_atomic_state(old_state);
 	unsigned int req_cdclk = old_intel_state->dev_cdclk;
+	unsigned int req_vco;
+
+	if (IS_GEMINILAKE(dev_priv))
+		req_vco = glk_de_pll_vco(dev_priv, req_cdclk);
+	else
+		req_vco = bxt_de_pll_vco(dev_priv, req_cdclk);
 
-	bxt_set_cdclk(to_i915(dev), req_cdclk);
+	bxt_set_cdclk(dev_priv, req_cdclk, req_vco);
 }
 
 static int intel_compute_max_dotclk(struct drm_i915_private *dev_priv)