drm/i915/cnl: Setup PAT Index.

Different from previous platforms, on CNL+ there's separated
registers for separated indexes.

v2: Remove comments regarding uncertainty around the table.
v3: Remove extra line (by Ben)

Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815232539.3562-1-rodrigo.vivi@intel.com
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index b2d7859..ed7cd9e 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2336,6 +2336,7 @@ enum i915_power_well_id {
 #define DONE_REG		_MMIO(0x40b0)
 #define GEN8_PRIVATE_PAT_LO	_MMIO(0x40e0)
 #define GEN8_PRIVATE_PAT_HI	_MMIO(0x40e0 + 4)
+#define GEN10_PAT_INDEX(index)	_MMIO(0x40e0 + index*4)
 #define BSD_HWS_PGA_GEN7	_MMIO(0x04180)
 #define BLT_HWS_PGA_GEN7	_MMIO(0x04280)
 #define VEBOX_HWS_PGA_GEN7	_MMIO(0x04380)