drm/i915: Store rawclk_freq in dev_priv

Generalize rawclk handling by storing it in dev_priv.

Presumably our hrawclk readout works at least for CTG and ELK
since we've been using it for DP AUX on those platforms. There
are no real docs anymore after configdb vanished, so the only
reference is the public CTG GMCH spec. What bits are listed in
that doc match our code. The ELK GMCH spec have no relevant
details unfortunately.

The PNV situation is less clear. Starting from
commit aa17cdb4f836 ("drm/i915: initialize backlight max from VBT")
we assume that the CTG/ELK hrawclk readout works for PNV as well.
At least the results *seem* reasonable for one PNV machine (Lenovo
Ideapad S10-3t). Sadly the PNV GMCH spec doesn't have the goods on
the relevant register either.

So let's keep assuming it works for PNV,ELK,CTG and read it out on
those platforms. G33 also has hrawclk according to some notes
in BSpec, but we don't actually need it for anything, so let's not
even try to read it out there.

v2: Rebase due to IS_VALLYVIEW vs. IS_CHERRYVIEW split
    Use KHz() all over, and kill off a few useless temp variables

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456932138-14004-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 5a13879..2625652 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -674,13 +674,13 @@
 static uint32_t i9xx_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
 {
 	struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
-	struct drm_device *dev = intel_dig_port->base.base.dev;
+	struct drm_i915_private *dev_priv = to_i915(intel_dig_port->base.base.dev);
 
 	/*
 	 * The clock divider is based off the hrawclk, and would like to run at
 	 * 2MHz.  So, take the hrawclk value and divide by 2 and use that
 	 */
-	return index ? 0 : DIV_ROUND_CLOSEST(intel_hrawclk(dev), 2);
+	return index ? 0 : DIV_ROUND_CLOSEST(dev_priv->rawclk_freq, 2000);
 }
 
 static uint32_t ilk_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
@@ -692,12 +692,10 @@
 	if (index)
 		return 0;
 
-	if (intel_dig_port->port == PORT_A) {
+	if (intel_dig_port->port == PORT_A)
 		return DIV_ROUND_CLOSEST(dev_priv->cdclk_freq, 2000);
-
-	} else {
-		return DIV_ROUND_CLOSEST(intel_pch_rawclk(dev), 2);
-	}
+	else
+		return DIV_ROUND_CLOSEST(dev_priv->rawclk_freq, 2000);
 }
 
 static uint32_t hsw_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
@@ -718,7 +716,7 @@
 		default: return 0;
 		}
 	} else  {
-		return index ? 0 : DIV_ROUND_CLOSEST(intel_pch_rawclk(dev), 2);
+		return index ? 0 : DIV_ROUND_CLOSEST(dev_priv->rawclk_freq, 2000);
 	}
 }
 
@@ -5268,7 +5266,7 @@
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	u32 pp_on, pp_off, pp_div, port_sel = 0;
-	int div = HAS_PCH_SPLIT(dev) ? intel_pch_rawclk(dev) : intel_hrawclk(dev);
+	int div = dev_priv->rawclk_freq / 1000;
 	i915_reg_t pp_on_reg, pp_off_reg, pp_div_reg, pp_ctrl_reg;
 	enum port port = dp_to_dig_port(intel_dp)->port;
 	const struct edp_power_seq *seq = &intel_dp->pps_delays;