drm/radeon/kms: vram sizing on certain r100 chips needs workaround.

If an rn50/r100/m6/m7 GPU has < 64MB RAM, i.e. 8/16/32, the
aperture used to calculate the MC_FB_LOCATION needs to be worked
out from the CONFIG_APER_SIZE register, and not the actual vram size.

TTM VRAM size was also being initialised wrong, use actual vram size
to initialise it.

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
index 1254208..cded518 100644
--- a/drivers/gpu/drm/radeon/radeon_gem.c
+++ b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -157,9 +157,9 @@
 	struct radeon_device *rdev = dev->dev_private;
 	struct drm_radeon_gem_info *args = data;
 
-	args->vram_size = rdev->mc.vram_size;
+	args->vram_size = rdev->mc.real_vram_size;
 	/* FIXME: report somethings that makes sense */
-	args->vram_visible = rdev->mc.vram_size - (4 * 1024 * 1024);
+	args->vram_visible = rdev->mc.real_vram_size - (4 * 1024 * 1024);
 	args->gart_size = rdev->mc.gtt_size;
 	return 0;
 }