drm/i915: Update the GGTT size/alignment query functions

In order to be consistent with other address space functions, we want to
pass around 64-bit sizes, even though all known global GTT are limited
to 4GiB. Similarly, we are trying to be consistent in using the _ggtt_
nomenclature when referring to the special global GTT.

v2: Update docs to consistently state "global GTT".

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470324762-2545-11-git-send-email-chris@chris-wilson.co.uk
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 1e13693..b6e56ec 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3241,11 +3241,9 @@
 int i915_gem_open(struct drm_device *dev, struct drm_file *file);
 void i915_gem_release(struct drm_device *dev, struct drm_file *file);
 
-uint32_t
-i915_gem_get_gtt_size(struct drm_device *dev, uint32_t size, int tiling_mode);
-uint32_t
-i915_gem_get_gtt_alignment(struct drm_device *dev, uint32_t size,
-			    int tiling_mode, bool fenced);
+u64 i915_gem_get_ggtt_size(struct drm_device *dev, u64 size, int tiling_mode);
+u64 i915_gem_get_ggtt_alignment(struct drm_device *dev, u64 size,
+				int tiling_mode, bool fenced);
 
 int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
 				    enum i915_cache_level cache_level);