diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index 8d0f2f99ddbf49c3df834b6d40d2b23cafbb81ea..7965415b47152f307a84e2823ccdcf8a2c2ff66f 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -1579,9 +1579,8 @@ static void amdvi_sysbus_realize(DeviceState *dev, Error **errp)
     /* set up MMIO */
     memory_region_init_io(&s->mmio, OBJECT(s), &mmio_mem_ops, s, "amdvi-mmio",
                           AMDVI_MMIO_SIZE);
-
-    sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->mmio);
-    sysbus_mmio_map(SYS_BUS_DEVICE(s), 0, AMDVI_BASE_ADDR);
+    memory_region_add_subregion(get_system_memory(), AMDVI_BASE_ADDR,
+                                &s->mmio);
     pci_setup_iommu(bus, amdvi_host_dma_iommu, s);
     amdvi_init(s);
 }