drm/radeon/kms: rs6xx/rs740: clamp vram to aperture size

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 00bc71f..c4bdfaf 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -306,9 +306,7 @@
 
 void rs600_gpu_init(struct radeon_device *rdev)
 {
-	/* FIXME: HDP same place on rs600 ? */
 	r100_hdp_reset(rdev);
-	/* FIXME: is this correct ? */
 	r420_pipes_init(rdev);
 	/* Wait for mc idle */
 	if (rs600_mc_wait_for_idle(rdev))
@@ -317,7 +315,6 @@
 
 void rs600_vram_info(struct radeon_device *rdev)
 {
-	/* FIXME: to do or is these values sane ? */
 	rdev->mc.vram_is_ddr = true;
 	rdev->mc.vram_width = 128;
 
@@ -326,6 +323,12 @@
 
 	rdev->mc.aper_base = drm_get_resource_start(rdev->ddev, 0);
 	rdev->mc.aper_size = drm_get_resource_len(rdev->ddev, 0);
+
+	if (rdev->mc.mc_vram_size > rdev->mc.aper_size)
+		rdev->mc.mc_vram_size = rdev->mc.aper_size;
+
+	if (rdev->mc.real_vram_size > rdev->mc.aper_size)
+		rdev->mc.real_vram_size = rdev->mc.aper_size;
 }
 
 void rs600_bandwidth_update(struct radeon_device *rdev)