diff --git a/sys/arm/arm/ofw_machdep.c b/sys/arm/arm/ofw_machdep.c
index 59b85c6cde7..9c60775b301 100644
--- a/sys/arm/arm/ofw_machdep.c
+++ b/sys/arm/arm/ofw_machdep.c
@@ -38,7 +38,7 @@ __FBSDID("$FreeBSD$");
 
 int
 OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
-    bus_space_handle_t *handle)
+    bus_space_handle_t *handle, bus_size_t *sz)
 {
 	bus_addr_t addr;
 	bus_size_t size;
@@ -66,6 +66,10 @@ OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
 	*tag = fdtbus_bs_tag;
 	flags = 0;
 #endif
+
+	if (sz != NULL)
+		*sz = size;
+
 	return (bus_space_map(*tag, addr, size, flags, handle));
 }
 
diff --git a/sys/arm64/arm64/ofw_machdep.c b/sys/arm64/arm64/ofw_machdep.c
index 6a0b714cd20..3941c1d3561 100644
--- a/sys/arm64/arm64/ofw_machdep.c
+++ b/sys/arm64/arm64/ofw_machdep.c
@@ -39,7 +39,7 @@ extern struct bus_space memmap_bus;
 
 int
 OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
-    bus_space_handle_t *handle)
+    bus_space_handle_t *handle, bus_size_t *sz)
 {
 	bus_addr_t addr;
 	bus_size_t size;
@@ -50,5 +50,9 @@ OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
 		return (err);
 
 	*tag = &memmap_bus;
+
+	if (sz != NULL)
+		*sz = size;
+
 	return (bus_space_map(*tag, addr, size, 0, handle));
 }
diff --git a/sys/dev/ofw/openfirm.h b/sys/dev/ofw/openfirm.h
index acfd2d28448..e616efcbc48 100644
--- a/sys/dev/ofw/openfirm.h
+++ b/sys/dev/ofw/openfirm.h
@@ -176,7 +176,7 @@ int		OF_interpret(const char *cmd, int nreturns, ...);
  */
 #ifndef __sparc64__
 int		OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *ptag,
-		    bus_space_handle_t *phandle);
+		    bus_space_handle_t *phandle, bus_size_t *sz);
 #endif
 
 #endif /* _KERNEL */
diff --git a/sys/dev/tsec/if_tsec_fdt.c b/sys/dev/tsec/if_tsec_fdt.c
index ccc7c948767..ab4bffc0193 100644
--- a/sys/dev/tsec/if_tsec_fdt.c
+++ b/sys/dev/tsec/if_tsec_fdt.c
@@ -167,7 +167,7 @@ tsec_fdt_attach(device_t dev)
 	}
 
 	phy = OF_node_from_xref(phy);
-	OF_decode_addr(OF_parent(phy), 0, &sc->phy_bst, &sc->phy_bsh);
+	OF_decode_addr(OF_parent(phy), 0, &sc->phy_bst, &sc->phy_bsh, NULL);
 	OF_getencprop(phy, "reg", &sc->phyaddr, sizeof(sc->phyaddr));
 
 	/* Init timer */
diff --git a/sys/dev/uart/uart_cpu_fdt.c b/sys/dev/uart/uart_cpu_fdt.c
index 1a4af9da800..6eb40f0d49d 100644
--- a/sys/dev/uart/uart_cpu_fdt.c
+++ b/sys/dev/uart/uart_cpu_fdt.c
@@ -212,5 +212,5 @@ uart_cpu_getdev(int devtype, struct uart_devinfo *di)
 	di->stopbits = 1;
 	di->parity = UART_PARITY_NONE;
 
-	return (OF_decode_addr(node, 0, &di->bas.bst, &di->bas.bsh));
+	return (OF_decode_addr(node, 0, &di->bas.bst, &di->bas.bsh, NULL));
 }
diff --git a/sys/dev/uart/uart_cpu_powerpc.c b/sys/dev/uart/uart_cpu_powerpc.c
index e41ceaea82a..8d9840577eb 100644
--- a/sys/dev/uart/uart_cpu_powerpc.c
+++ b/sys/dev/uart/uart_cpu_powerpc.c
@@ -180,7 +180,7 @@ uart_cpu_getdev(int devtype, struct uart_devinfo *di)
 	if (class == NULL)
 		return (ENXIO);
 
-	error = OF_decode_addr(input, 0, &di->bas.bst, &di->bas.bsh);
+	error = OF_decode_addr(input, 0, &di->bas.bst, &di->bas.bsh, NULL);
 	if (error)
 		return (error);
 
diff --git a/sys/dev/vt/hw/ofwfb/ofwfb.c b/sys/dev/vt/hw/ofwfb/ofwfb.c
index c3ac185c910..0776a8e622d 100644
--- a/sys/dev/vt/hw/ofwfb/ofwfb.c
+++ b/sys/dev/vt/hw/ofwfb/ofwfb.c
@@ -480,7 +480,8 @@ ofwfb_init(struct vt_device *vd)
 			return (CN_DEAD);
 
 	#if defined(__powerpc__)
-		OF_decode_addr(node, fb_phys, &sc->sc_memt, &sc->fb.fb_vbase);
+		OF_decode_addr(node, fb_phys, &sc->sc_memt, &sc->fb.fb_vbase,
+		    NULL);
 		sc->fb.fb_pbase = sc->fb.fb_vbase; /* 1:1 mapped */
 		#ifdef __powerpc64__
 		/* Real mode under a hypervisor probably doesn't cover FB */
diff --git a/sys/mips/mips/ofw_machdep.c b/sys/mips/mips/ofw_machdep.c
index 82e295912c7..26bc2600fb1 100644
--- a/sys/mips/mips/ofw_machdep.c
+++ b/sys/mips/mips/ofw_machdep.c
@@ -38,7 +38,7 @@ __FBSDID("$FreeBSD$");
 
 int
 OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
-    bus_space_handle_t *handle)
+    bus_space_handle_t *handle, bus_size_t *sz)
 {
 	bus_addr_t addr;
 	bus_size_t size;
@@ -66,5 +66,9 @@ OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
 	*tag = fdtbus_bs_tag;
 	flags = 0;
 #endif
+
+	if (sz != NULL)
+		*sz = size;
+
 	return (bus_space_map(*tag, addr, size, flags, handle));
 }
diff --git a/sys/powerpc/ofw/ofw_machdep.c b/sys/powerpc/ofw/ofw_machdep.c
index d2bb77b06ac..3051eb3fc20 100644
--- a/sys/powerpc/ofw/ofw_machdep.c
+++ b/sys/powerpc/ofw/ofw_machdep.c
@@ -565,7 +565,7 @@ OF_getetheraddr(device_t dev, u_char *addr)
  */
 int
 OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
-    bus_space_handle_t *handle)
+    bus_space_handle_t *handle, bus_size_t *sz)
 {
 	bus_addr_t addr;
 	bus_size_t size;
@@ -585,6 +585,9 @@ OF_decode_addr(phandle_t dev, int regno, bus_space_tag_t *tag,
 		    BUS_SPACE_MAP_PREFETCHABLE: 0;
 	}
 
+	if (sz != NULL)
+		*sz = size;
+
 	return (bus_space_map(*tag, addr, size, flags, handle));
 }
 
diff --git a/sys/powerpc/ofw/ofw_syscons.c b/sys/powerpc/ofw/ofw_syscons.c
index 7dc51f9888c..b766485ed17 100644
--- a/sys/powerpc/ofw/ofw_syscons.c
+++ b/sys/powerpc/ofw/ofw_syscons.c
@@ -342,7 +342,7 @@ ofwfb_configure(int flags)
 		if (fb_phys == sc->sc_num_pciaddrs)
 			return (0);
 
-		OF_decode_addr(node, fb_phys, &sc->sc_tag, &sc->sc_addr);
+		OF_decode_addr(node, fb_phys, &sc->sc_tag, &sc->sc_addr, NULL);
 	}
 
 	ofwfb_init(0, &sc->sc_va, 0);