drm/i915: Read out VGA dotclock properly on LPT

Rather than assume the VGA dotclock is really the FDI based thing,
let's read out the real thing via iclkip, and after readout it'll
get to compare it with the FDI based number to make sure they're
in sync.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455738073-14502-6-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index f76cbf3..71abf57 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7362,9 +7362,11 @@
 /* SBI offsets */
 #define  SBI_SSCDIVINTPHASE			0x0200
 #define  SBI_SSCDIVINTPHASE6			0x0600
-#define   SBI_SSCDIVINTPHASE_DIVSEL_MASK	((0x7f)<<1)
+#define   SBI_SSCDIVINTPHASE_DIVSEL_SHIFT	1
+#define   SBI_SSCDIVINTPHASE_DIVSEL_MASK	(0x7f<<1)
 #define   SBI_SSCDIVINTPHASE_DIVSEL(x)		((x)<<1)
-#define   SBI_SSCDIVINTPHASE_INCVAL_MASK	((0x7f)<<8)
+#define   SBI_SSCDIVINTPHASE_INCVAL_SHIFT	8
+#define   SBI_SSCDIVINTPHASE_INCVAL_MASK	(0x7f<<8)
 #define   SBI_SSCDIVINTPHASE_INCVAL(x)		((x)<<8)
 #define   SBI_SSCDIVINTPHASE_DIR(x)		((x)<<15)
 #define   SBI_SSCDIVINTPHASE_PROPAGATE		(1<<0)
@@ -7374,6 +7376,8 @@
 #define   SBI_SSCCTL_PATHALT			(1<<3)
 #define   SBI_SSCCTL_DISABLE			(1<<0)
 #define  SBI_SSCAUXDIV6				0x0610
+#define   SBI_SSCAUXDIV_FINALDIV2SEL_SHIFT	4
+#define   SBI_SSCAUXDIV_FINALDIV2SEL_MASK	(1<<4)
 #define   SBI_SSCAUXDIV_FINALDIV2SEL(x)		((x)<<4)
 #define  SBI_DBUFF0				0x2a00
 #define  SBI_GEN0				0x1f00