drm/i915: Avoid pointer arithmetic in calculating plane surface offset

VMA offsets are 64 bits. Plane surface offsets are in ggtt and
the hardware register to set this is thus 32 bits. Be explicit
about these and convert carefully to from vma to final size.

This will make sparse happy by not creating 32bit pointers out
of 64bit vma offsets.

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446204375-29831-1-git-send-email-mika.kuoppala@intel.com
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 2e05c7e..5a938ff 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2915,13 +2915,13 @@
 	}
 }
 
-unsigned long intel_plane_obj_offset(struct intel_plane *intel_plane,
-				     struct drm_i915_gem_object *obj,
-				     unsigned int plane)
+u32 intel_plane_obj_offset(struct intel_plane *intel_plane,
+			   struct drm_i915_gem_object *obj,
+			   unsigned int plane)
 {
 	const struct i915_ggtt_view *view = &i915_ggtt_view_normal;
 	struct i915_vma *vma;
-	unsigned char *offset;
+	u64 offset;
 
 	if (intel_rotation_90_or_270(intel_plane->base.state->rotation))
 		view = &i915_ggtt_view_rotated;
@@ -2931,14 +2931,16 @@
 		view->type))
 		return -1;
 
-	offset = (unsigned char *)vma->node.start;
+	offset = vma->node.start;
 
 	if (plane == 1) {
 		offset += vma->ggtt_view.rotation_info.uv_start_page *
 			  PAGE_SIZE;
 	}
 
-	return (unsigned long)offset;
+	WARN_ON(upper_32_bits(offset));
+
+	return lower_32_bits(offset);
 }
 
 static void skl_detach_scaler(struct intel_crtc *intel_crtc, int id)
@@ -3064,7 +3066,7 @@
 	u32 tile_height, plane_offset, plane_size;
 	unsigned int rotation;
 	int x_offset, y_offset;
-	unsigned long surf_addr;
+	u32 surf_addr;
 	struct intel_crtc_state *crtc_state = intel_crtc->config;
 	struct intel_plane_state *plane_state;
 	int src_x = 0, src_y = 0, src_w = 0, src_h = 0;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 92518b4..0f8fd14 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1199,9 +1199,9 @@
 int skl_update_scaler_crtc(struct intel_crtc_state *crtc_state);
 int skl_max_scale(struct intel_crtc *crtc, struct intel_crtc_state *crtc_state);
 
-unsigned long intel_plane_obj_offset(struct intel_plane *intel_plane,
-				     struct drm_i915_gem_object *obj,
-				     unsigned int plane);
+u32 intel_plane_obj_offset(struct intel_plane *intel_plane,
+			   struct drm_i915_gem_object *obj,
+			   unsigned int plane);
 
 u32 skl_plane_ctl_format(uint32_t pixel_format);
 u32 skl_plane_ctl_tiling(uint64_t fb_modifier);
diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 4276c13..a2c15f8 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -194,7 +194,7 @@
 	u32 plane_ctl, stride_div, stride;
 	const struct drm_intel_sprite_colorkey *key =
 		&to_intel_plane_state(drm_plane->state)->ckey;
-	unsigned long surf_addr;
+	u32 surf_addr;
 	u32 tile_height, plane_offset, plane_size;
 	unsigned int rotation;
 	int x_offset, y_offset;