diff --git a/sys/arm64/iommu/iommu.c b/sys/arm64/iommu/iommu.c
--- a/sys/arm64/iommu/iommu.c
+++ b/sys/arm64/iommu/iommu.c
@@ -248,6 +248,7 @@
 	return (NULL);
 }
 
+#ifdef FDT
 struct iommu_ctx *
 iommu_get_ctx_ofw(device_t dev, int channel)
 {
@@ -333,6 +334,7 @@
 
 	return (ioctx);
 }
+#endif
 
 struct iommu_ctx *
 iommu_get_ctx(struct iommu_unit *iommu, device_t requester,
diff --git a/sys/arm64/iommu/iommu_if.m b/sys/arm64/iommu/iommu_if.m
--- a/sys/arm64/iommu/iommu_if.m
+++ b/sys/arm64/iommu/iommu_if.m
@@ -32,6 +32,8 @@
 # $FreeBSD$
 #
 
+#include "opt_platform.h"
+
 #include <sys/types.h>
 #include <sys/taskqueue.h>
 #include <sys/bus.h>
@@ -138,6 +140,7 @@
 	struct iommu_ctx	*ioctx;
 };
 
+#ifdef FDT
 #
 # Notify controller we have machine-dependent data.
 #
@@ -147,3 +150,4 @@
 	pcell_t *cells;
 	int ncells;
 };
+#endif
diff --git a/sys/arm64/iommu/smmu_fdt.c b/sys/arm64/iommu/smmu_fdt.c
--- a/sys/arm64/iommu/smmu_fdt.c
+++ b/sys/arm64/iommu/smmu_fdt.c
@@ -202,7 +202,5 @@
 DEFINE_CLASS_1(smmu, smmu_fdt_driver, smmu_fdt_methods,
     sizeof(struct smmu_softc), smmu_driver);
 
-static devclass_t smmu_fdt_devclass;
-
-EARLY_DRIVER_MODULE(smmu, simplebus, smmu_fdt_driver, smmu_fdt_devclass,
-    0, 0, BUS_PASS_INTERRUPT + BUS_PASS_ORDER_MIDDLE);
+EARLY_DRIVER_MODULE(smmu, simplebus, smmu_fdt_driver, 0, 0,
+    BUS_PASS_INTERRUPT + BUS_PASS_ORDER_MIDDLE);