drm/i915: Track full cdclk state for the logical and actual cdclk frequencies

The current dev_cdclk vs. cdclk vs. atomic_cdclk_freq is quite a mess.
So here I'm introducing the "actual" and "logical" naming for our
cdclk state. "actual" is what we'll bash into the hardware and "logical"
is what everyone should use for state computaion/checking and whatnot.
We'll track both using the intel_cdclk_state as both will need other
differing parameters than just the actual cdclk frequency.

While doing that we can at the same time unify the appearance of the
.modeset_calc_cdclk() implementations a little bit.

v2: Commit dev_priv->cdclk.actual since that already has the
    new state by the time .modeset_commit_cdclk() is called.
v3: s/locical/logical/ and improve the docs a bit

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/20170120182205.8141-9-ville.syrjala@linux.intel.com
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index ba0728c..97d84819 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -333,13 +333,20 @@ struct dpll {
 struct intel_atomic_state {
 	struct drm_atomic_state base;
 
-	unsigned int cdclk;
+	struct {
+		/*
+		 * Logical state of cdclk (used for all scaling, watermark,
+		 * etc. calculations and checks). This is computed as if all
+		 * enabled crtcs were active.
+		 */
+		struct intel_cdclk_state logical;
 
-	/*
-	 * Calculated device cdclk, can be different from cdclk
-	 * only when all crtc's are DPMS off.
-	 */
-	unsigned int dev_cdclk;
+		/*
+		 * Actual state of cdclk, can be different from the logical
+		 * state only when all crtc's are DPMS off.
+		 */
+		struct intel_cdclk_state actual;
+	} cdclk;
 
 	bool dpll_set, modeset;
 
@@ -356,9 +363,6 @@ struct intel_atomic_state {
 	unsigned int active_crtcs;
 	unsigned int min_pixclk[I915_MAX_PIPES];
 
-	/* SKL/KBL Only */
-	unsigned int cdclk_pll_vco;
-
 	struct intel_shared_dpll_state shared_dpll[I915_NUM_PLLS];
 
 	/*