drm/i915: Pass modifier instead of tiling_mode to gen4_compute_page_offset()

In preparation for handling more than X tiling, pass the fb modifier to
gen4_compute_page_offset() instead of the obj->tiling_mode.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452625717-9713-2-git-send-email-ville.syrjala@linux.intel.com
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index e27954d..0155382 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1198,8 +1198,8 @@
 #define assert_pipe_disabled(d, p) assert_pipe(d, p, false)
 unsigned long intel_gen4_compute_page_offset(struct drm_i915_private *dev_priv,
 					     int *x, int *y,
-					     unsigned int tiling_mode,
-					     unsigned int bpp,
+					     uint64_t fb_modifier,
+					     unsigned int cpp,
 					     unsigned int pitch);
 void intel_prepare_reset(struct drm_device *dev);
 void intel_finish_reset(struct drm_device *dev);