+ /*
+ * Order is important here to make sure any unity map requirements are
+ * fulfilled. The unity mappings are created and written to the device
+ * table during the amd_iommu_init_api() call.
+ *
+ * After that we call init_device_table_dma() to make sure any
+ * uninitialized DTE will block DMA, and in the end we flush the caches
+ * of all IOMMUs to make sure the changes to the device table are
+ * active.
+ */
+ ret = amd_iommu_init_api();
+