drm/i915: Extract tile_row_size for fencing

Computing the tile row size of a tiled object (for use with fence
registers) is repeated, so extract it to a common helper.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170109161613.11881-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

drivers/gpu/drm/i915/i915_gem.c

@@ -1696,12 +1696,7 @@ i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
 
 static unsigned int tile_row_pages(struct drm_i915_gem_object *obj)
 {
-	u64 size;
-
-	size = i915_gem_object_get_stride(obj);
-	size *= i915_gem_object_get_tiling(obj) == I915_TILING_Y ? 32 : 8;
-
-	return size >> PAGE_SHIFT;
+	return i915_gem_object_get_tile_row_size(obj) >> PAGE_SHIFT;
 }
 
 /**

drivers/gpu/drm/i915/i915_gem_fence_reg.c

@@ -77,16 +77,14 @@ static void i965_write_fence_reg(struct drm_i915_fence_reg *fence,
 
 	val = 0;
 	if (vma) {
-		unsigned int tiling = i915_gem_object_get_tiling(vma->obj);
-		bool is_y_tiled = tiling == I915_TILING_Y;
 		unsigned int stride = i915_gem_object_get_stride(vma->obj);
-		u32 row_size = stride * (is_y_tiled ? 32 : 8);
+		u32 row_size = i915_gem_object_get_tile_row_size(vma->obj);
 		u32 size = rounddown((u32)vma->node.size, row_size);
 
 		val = ((vma->node.start + size - 4096) & 0xfffff000) << 32;
 		val |= vma->node.start & 0xfffff000;
 		val |= (u64)((stride / 128) - 1) << fence_pitch_shift;
-		if (is_y_tiled)
+		if (i915_gem_object_get_tiling(vma->obj) == I915_TILING_Y)
 			val |= BIT(I965_FENCE_TILING_Y_SHIFT);
 		val |= I965_FENCE_REG_VALID;
 	}

drivers/gpu/drm/i915/i915_gem_object.h

@@ -317,6 +317,26 @@ i915_gem_object_get_stride(struct drm_i915_gem_object *obj)
 	return obj->tiling_and_stride & STRIDE_MASK;
 }
 
+static inline unsigned int
+i915_gem_tile_height(unsigned int tiling)
+{
+	GEM_BUG_ON(!tiling);
+	return tiling == I915_TILING_Y ? 32 : 8;
+}
+
+static inline unsigned int
+i915_gem_object_get_tile_height(struct drm_i915_gem_object *obj)
+{
+	return i915_gem_tile_height(i915_gem_object_get_tiling(obj));
+}
+
+static inline unsigned int
+i915_gem_object_get_tile_row_size(struct drm_i915_gem_object *obj)
+{
+	return (i915_gem_object_get_stride(obj) *
+		i915_gem_object_get_tile_height(obj));
+}
+
 static inline struct intel_engine_cs *
 i915_gem_object_last_write_engine(struct drm_i915_gem_object *obj)
 {