drm/radeon/kms/r600: clamp vram to aperture size

r6xx and r7xx was missing this.  We don't support
non-CPU accessible vram yet.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/gpu/drm/radeon/r600.c

@@ -380,6 +380,13 @@ int r600_mc_init(struct radeon_device *rdev)
 	/* Setup GPU memory space */
 	rdev->mc.mc_vram_size = RREG32(CONFIG_MEMSIZE);
 	rdev->mc.real_vram_size = RREG32(CONFIG_MEMSIZE);
+
+	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;
+
 	if (rdev->flags & RADEON_IS_AGP) {
 		r = radeon_agp_init(rdev);
 		if (r)

drivers/gpu/drm/radeon/rv770.c

@@ -801,6 +801,13 @@ int rv770_mc_init(struct radeon_device *rdev)
 	/* Setup GPU memory space */
 	rdev->mc.mc_vram_size = RREG32(CONFIG_MEMSIZE);
 	rdev->mc.real_vram_size = RREG32(CONFIG_MEMSIZE);
+
+	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;
+
 	if (rdev->flags & RADEON_IS_AGP) {
 		r = radeon_agp_init(rdev);
 		if (r)