drm/radeon/kms: fix vram start calculation on ontario (v2)

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/evergreend.h b/drivers/gpu/drm/radeon/evergreend.h
index 87fcaba..5b869ce 100644
--- a/drivers/gpu/drm/radeon/evergreend.h
+++ b/drivers/gpu/drm/radeon/evergreend.h
@@ -202,6 +202,7 @@
 #define	MC_VM_AGP_BOT					0x202C
 #define	MC_VM_AGP_BASE					0x2030
 #define	MC_VM_FB_LOCATION				0x2024
+#define	MC_FUS_VM_FB_OFFSET				0x2898
 #define	MC_VM_MB_L1_TLB0_CNTL				0x2234
 #define	MC_VM_MB_L1_TLB1_CNTL				0x2238
 #define	MC_VM_MB_L1_TLB2_CNTL				0x223C