drm/i915: Add HAS_CORE_RING_FREQ macro

Added a new HAS_CORE_RING_FREQ macro, currently used in
gen6_update_ring_freq & i915_ring_freq_table debugfs function.
The programming & read of ring frequency table is needed for newer
GEN(>=6) platforms, except VLV/CHV.

Issue: VIZ-5144
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Akash Goel <akash.goel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 45bbc19..6611356 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2548,6 +2548,9 @@
 #define HAS_RESOURCE_STREAMER(dev) (IS_HASWELL(dev) || \
 				    INTEL_INFO(dev)->gen >= 8)
 
+#define HAS_CORE_RING_FREQ(dev)	(INTEL_INFO(dev)->gen >= 6 && \
+				 !IS_VALLEYVIEW(dev))
+
 #define INTEL_PCH_DEVICE_ID_MASK		0xff00
 #define INTEL_PCH_IBX_DEVICE_ID_TYPE		0x3b00
 #define INTEL_PCH_CPT_DEVICE_ID_TYPE		0x1c00