diff --git a/src/soc/amd/stoneyridge/northbridge.c b/src/soc/amd/stoneyridge/northbridge.c
index 068ba56..ccfa9cb 100644
--- a/src/soc/amd/stoneyridge/northbridge.c
+++ b/src/soc/amd/stoneyridge/northbridge.c
@@ -276,7 +276,7 @@
  */
 void amd_initcpuio(void)
 {
-	uintptr_t topmem = amd_topmem();
+	uintptr_t topmem = get_top_of_mem_below_4gb();
 	uintptr_t base, limit;
 
 	/* Enable legacy video routing: D18F1xF4 VGA Enable */