diff --git a/sys/dev/extres/syscon/syscon.c b/sys/dev/extres/syscon/syscon.c
index d1f4fe0838b0..2ab1bec4f140 100644
--- a/sys/dev/extres/syscon/syscon.c
+++ b/sys/dev/extres/syscon/syscon.c
@@ -67,6 +67,12 @@ typedef TAILQ_HEAD(syscon_list, syscon) syscon_list_t;
  */
 static int syscon_method_init(struct syscon *syscon);
 static int syscon_method_uninit(struct syscon *syscon);
+static uint32_t syscon_method_read_4(struct syscon *syscon, bus_size_t offset);
+static int syscon_method_write_4(struct syscon *syscon, bus_size_t offset,
+    uint32_t val);
+static int syscon_method_modify_4(struct syscon *syscon, bus_size_t offset,
+    uint32_t clear_bits, uint32_t set_bits);
+
 
 MALLOC_DEFINE(M_SYSCON, "syscon", "Syscon driver");
 
@@ -80,6 +86,9 @@ SX_SYSINIT(syscon_topology, &syscon_topo_lock, "Syscon topology lock");
 static syscon_method_t syscon_methods[] = {
 	SYSCONMETHOD(syscon_init,	syscon_method_init),
 	SYSCONMETHOD(syscon_uninit,	syscon_method_uninit),
+	SYSCONMETHOD(syscon_read_4,	syscon_method_read_4),
+	SYSCONMETHOD(syscon_write_4,	syscon_method_write_4),
+	SYSCONMETHOD(syscon_modify_4,	syscon_method_modify_4),
 
 	SYSCONMETHOD_END
 };
@@ -115,6 +124,39 @@ syscon_get_softc(struct syscon *syscon)
 	return (syscon->softc);
 };
 
+static uint32_t
+syscon_method_read_4(struct syscon *syscon, bus_size_t offset)
+{
+	uint32_t val;
+
+	SYSCON_DEVICE_LOCK(syscon->pdev);
+	val = SYSCON_UNLOCKED_READ_4(syscon, offset);
+	SYSCON_DEVICE_UNLOCK(syscon->pdev);
+	return(val);
+}
+
+static int
+syscon_method_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val)
+{
+	int	rv;
+
+	SYSCON_DEVICE_LOCK(syscon->pdev);
+	rv = SYSCON_UNLOCKED_WRITE_4(syscon, offset, val);
+	SYSCON_DEVICE_UNLOCK(syscon->pdev);
+	return(rv);
+}
+
+static int
+syscon_method_modify_4(struct syscon *syscon, bus_size_t offset,
+    uint32_t clear_bits, uint32_t set_bits)
+{
+	int	rv;
+
+	SYSCON_DEVICE_LOCK(syscon->pdev);
+	rv = SYSCON_UNLOCKED_MODIFY_4(syscon, offset, clear_bits, set_bits);
+	SYSCON_DEVICE_UNLOCK(syscon->pdev);
+	return(rv);
+}
 /*
  * Create and initialize syscon object, but do not register it.
  */
@@ -254,14 +296,3 @@ syscon_get_by_ofw_property(device_t cdev, phandle_t cnode, char *name,
 	return (0);
 }
 #endif
-
-int
-syscon_get_handle_default(device_t dev, struct syscon **syscon)
-{
-	device_t parent;
-
-	parent = device_get_parent(dev);
-	if (parent == NULL)
-		return (ENODEV);
-	return (SYSCON_GET_HANDLE(parent, syscon));
-}
diff --git a/sys/dev/extres/syscon/syscon_generic.c b/sys/dev/extres/syscon/syscon_generic.c
index b68d3cdf6786..7e6c040bfb86 100644
--- a/sys/dev/extres/syscon/syscon_generic.c
+++ b/sys/dev/extres/syscon/syscon_generic.c
@@ -55,11 +55,12 @@ __FBSDID("$FreeBSD$");
 
 MALLOC_DECLARE(M_SYSCON);
 
-static uint32_t syscon_generic_read_4(struct syscon *syscon, bus_size_t offset);
-static int syscon_generic_write_4(struct syscon *syscon, bus_size_t offset,
-    uint32_t val);
-static int syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset,
-    uint32_t clear_bits, uint32_t set_bits);
+static uint32_t syscon_generic_unlocked_read_4(struct syscon *syscon,
+    bus_size_t offset);
+static int syscon_generic_unlocked_write_4(struct syscon *syscon,
+    bus_size_t offset, uint32_t val);
+static int syscon_generic_unlocked_modify_4(struct syscon *syscon,
+    bus_size_t offset, uint32_t clear_bits, uint32_t set_bits);
 static int syscon_generic_detach(device_t dev);
 /*
  * Generic syscon driver (FDT)
@@ -78,9 +79,9 @@ static struct ofw_compat_data compat_data[] = {
 #define SYSCON_ASSERT_UNLOCKED(_sc)	mtx_assert(&(_sc)->mtx, MA_NOTOWNED);
 
 static syscon_method_t syscon_generic_methods[] = {
-	SYSCONMETHOD(syscon_read_4,	syscon_generic_read_4),
-	SYSCONMETHOD(syscon_write_4,	syscon_generic_write_4),
-	SYSCONMETHOD(syscon_modify_4,	syscon_generic_modify_4),
+	SYSCONMETHOD(syscon_unlocked_read_4,  syscon_generic_unlocked_read_4),
+	SYSCONMETHOD(syscon_unlocked_write_4, syscon_generic_unlocked_write_4),
+	SYSCONMETHOD(syscon_unlocked_modify_4, syscon_generic_unlocked_modify_4),
 
 	SYSCONMETHOD_END
 };
@@ -88,50 +89,62 @@ DEFINE_CLASS_1(syscon_generic, syscon_generic_class, syscon_generic_methods,
     0, syscon_class);
 
 static uint32_t
-syscon_generic_read_4(struct syscon *syscon, bus_size_t offset)
+syscon_generic_unlocked_read_4(struct syscon *syscon, bus_size_t offset)
 {
 	struct syscon_generic_softc *sc;
 	uint32_t val;
 
 	sc = device_get_softc(syscon->pdev);
-
-	SYSCON_LOCK(sc);
+	SYSCON_ASSERT_UNLOCKED(sc);
 	val = bus_read_4(sc->mem_res, offset);
-	SYSCON_UNLOCK(sc);
 	return (val);
 }
 
 static int
-syscon_generic_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val)
+syscon_generic_unlocked_write_4(struct syscon *syscon, bus_size_t offset, uint32_t val)
 {
 	struct syscon_generic_softc *sc;
 
 	sc = device_get_softc(syscon->pdev);
-
-	SYSCON_LOCK(sc);
+	SYSCON_ASSERT_UNLOCKED(sc);
 	bus_write_4(sc->mem_res, offset, val);
-	SYSCON_UNLOCK(sc);
 	return (0);
 }
 
 static int
-syscon_generic_modify_4(struct syscon *syscon, bus_size_t offset,
+syscon_generic_unlocked_modify_4(struct syscon *syscon, bus_size_t offset,
     uint32_t clear_bits, uint32_t set_bits)
 {
 	struct syscon_generic_softc *sc;
 	uint32_t val;
 
 	sc = device_get_softc(syscon->pdev);
-
-	SYSCON_LOCK(sc);
+	SYSCON_ASSERT_UNLOCKED(sc);
 	val = bus_read_4(sc->mem_res, offset);
 	val &= ~clear_bits;
 	val |= set_bits;
 	bus_write_4(sc->mem_res, offset, val);
-	SYSCON_UNLOCK(sc);
 	return (0);
 }
 
+static void
+syscon_generic_lock(device_t dev)
+{
+	struct syscon_generic_softc *sc;
+
+	sc = device_get_softc(dev);
+	SYSCON_LOCK(sc);
+}
+
+static void
+syscon_generic_unlock(device_t dev)
+{
+	struct syscon_generic_softc *sc;
+
+	sc = device_get_softc(dev);
+	SYSCON_UNLOCK(sc);
+}
+
 static int
 syscon_generic_probe(device_t dev)
 {
@@ -211,6 +224,9 @@ static device_method_t syscon_generic_dmethods[] = {
 	DEVMETHOD(device_attach,	syscon_generic_attach),
 	DEVMETHOD(device_detach,	syscon_generic_detach),
 
+	DEVMETHOD(syscon_device_lock,	syscon_generic_lock),
+	DEVMETHOD(syscon_device_unlock,	syscon_generic_unlock),
+
 	DEVMETHOD_END
 };
 
diff --git a/sys/dev/extres/syscon/syscon_if.m b/sys/dev/extres/syscon/syscon_if.m
index 98008340cc9d..d6b88d2c35dd 100644
--- a/sys/dev/extres/syscon/syscon_if.m
+++ b/sys/dev/extres/syscon/syscon_if.m
@@ -35,6 +35,36 @@ HEADER {
 	int syscon_get_handle_default(device_t dev, struct syscon **syscon);
 }
 
+CODE {
+	#include <sys/systm.h>
+	#include <sys/bus.h>
+
+	int
+	syscon_get_handle_default(device_t dev, struct syscon **syscon)
+	{
+		device_t parent;
+
+		parent = device_get_parent(dev);
+		if (parent == NULL)
+			return (ENODEV);
+		return (SYSCON_GET_HANDLE(parent, syscon));
+	}
+
+	static void
+	syscon_device_lock_default(device_t dev)
+	{
+
+		panic("syscon_device_lock is not implemented");
+	};
+
+	static void
+	syscon_device_unlock_default(device_t dev)
+	{
+
+		panic("syscon_device_unlock is not implemented");
+	};
+}
+
 METHOD int init {
 	struct syscon	*syscon;
 };
@@ -64,6 +94,38 @@ METHOD int modify_4 {
 	uint32_t	set_bits;
 };
 
+/**
+ * Unlocked verion of access function
+ */
+METHOD uint32_t unlocked_read_4 {
+	struct syscon	*syscon;
+	bus_size_t	offset;
+};
+
+METHOD int unlocked_write_4 {
+	struct syscon	*syscon;
+	bus_size_t	offset;
+	uint32_t	val;
+};
+
+METHOD int unlocked_modify_4 {
+	struct syscon	*syscon;
+	bus_size_t	offset;
+	uint32_t	clear_bits;
+	uint32_t	set_bits;
+};
+
+/**
+* Locking for exclusive access to underlying device
+*/
+METHOD void device_lock {
+	device_t	dev;
+} DEFAULT syscon_device_lock_default;
+
+METHOD void device_unlock {
+	device_t	dev;
+} DEFAULT syscon_device_unlock_default;
+
 /**
  * Get syscon handle from parent driver
  */