diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index e0fc070..077d40f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1210,6 +1210,9 @@
 
 #define MCHBAR_MIRROR_BASE_SNB	0x140000
 
+/* Memory controller frequency in MCHBAR for Haswell (possible SNB+) */
+#define DCLK 0x5e04
+
 /** 915-945 and GM965 MCH register controlling DRAM channel access */
 #define DCC			0x10200
 #define DCC_ADDRESSING_MODE_SINGLE_CHANNEL		(0 << 0)
@@ -4390,6 +4393,7 @@
 #define   GEN6_DECODE_RC6_VID(vids)		(((vids) * 5) + 245)
 #define GEN6_PCODE_DATA				0x138128
 #define   GEN6_PCODE_FREQ_IA_RATIO_SHIFT	8
+#define   GEN6_PCODE_FREQ_RING_RATIO_SHIFT	16
 
 #define VLV_IOSF_DOORBELL_REQ			0x182100
 #define   IOSF_DEVFN_SHIFT			24