Index: sys/dev/extres/clk/clk.h
===================================================================
--- sys/dev/extres/clk/clk.h
+++ sys/dev/extres/clk/clk.h
@@ -112,6 +112,7 @@
 device_t clknode_get_device(struct clknode *clk);
 struct clknode *clknode_find_by_name(const char *name);
 struct clknode *clknode_find_by_id(struct clkdom *clkdom, intptr_t id);
+int clknode_list_freq(struct clknode *clknode, uint64_t *freq, int *freq_count);
 int clknode_get_freq(struct clknode *clknode, uint64_t *freq);
 int clknode_set_freq(struct clknode *clknode, uint64_t freq, int flags,
     int enablecnt);
@@ -127,6 +128,7 @@
 int clk_get_by_name(device_t dev, const char *name, clk_t *clk);
 int clk_get_by_id(device_t dev, struct clkdom *clkdom, intptr_t id, clk_t *clk);
 int clk_release(clk_t clk);
+int clk_list_freq(clk_t clk, uint64_t *freq, int *freq_count);
 int clk_get_freq(clk_t clk, uint64_t *freq);
 int clk_set_freq(clk_t clk, uint64_t freq, int flags);
 int clk_test_freq(clk_t clk, uint64_t freq, int flags);
Index: sys/dev/extres/clk/clk.c
===================================================================
--- sys/dev/extres/clk/clk.c
+++ sys/dev/extres/clk/clk.c
@@ -65,6 +65,8 @@
 
 /* Default clock methods. */
 static int clknode_method_init(struct clknode *clk, device_t dev);
+static int clknode_method_list_freq(struct clknode *clknode, uint64_t *freq,
+    int *count);
 static int clknode_method_recalc_freq(struct clknode *clk, uint64_t *freq);
 static int clknode_method_set_freq(struct clknode *clk, uint64_t fin,
     uint64_t *fout, int flags, int *stop);
@@ -76,6 +78,7 @@
  */
 static clknode_method_t clknode_methods[] = {
 	CLKNODEMETHOD(clknode_init,		clknode_method_init),
+	CLKNODEMETHOD(clknode_list_freq,	clknode_method_list_freq),
 	CLKNODEMETHOD(clknode_recalc_freq,	clknode_method_recalc_freq),
 	CLKNODEMETHOD(clknode_set_freq,		clknode_method_set_freq),
 	CLKNODEMETHOD(clknode_set_gate,		clknode_method_set_gate),
@@ -205,6 +208,13 @@
 	return (0);
 }
 
+static int
+clknode_method_list_freq(struct clknode *clknode, uint64_t *freq, int *count)
+{
+
+	return (0);
+}
+
 static int
 clknode_method_recalc_freq(struct clknode *clknode, uint64_t *freq)
 {
@@ -929,6 +939,20 @@
 /*
  * Real consumers executive
  */
+int
+clknode_list_freq(struct clknode *clknode, uint64_t *freq, int *freq_count)
+{
+	int rv;
+
+	CLK_TOPO_ASSERT();
+
+	CLKNODE_XLOCK(clknode);
+	rv = CLKNODE_LIST_FREQ(clknode, freq, freq_count);
+	CLKNODE_UNLOCK(clknode);
+
+	return (rv);
+}
+
 int
 clknode_get_freq(struct clknode *clknode, uint64_t *freq)
 {
@@ -1186,6 +1210,20 @@
 	return (rv);
 }
 
+int
+clk_list_freq(clk_t clk, uint64_t *freq, int *freq_count)
+{
+	int rv;
+	struct clknode *clknode;
+
+	clknode = clk->clknode;
+
+	CLK_TOPO_XLOCK();
+	rv = clknode_list_freq(clknode, freq, freq_count);
+	CLK_TOPO_UNLOCK();
+	return (rv);
+}
+
 int
 clk_set_freq(clk_t clk, uint64_t freq, int flags)
 {
Index: sys/dev/extres/clk/clknode_if.m
===================================================================
--- sys/dev/extres/clk/clknode_if.m
+++ sys/dev/extres/clk/clknode_if.m
@@ -40,6 +40,15 @@
 	device_t	dev;
 };
 
+#
+# List all possible frequencies.
+#
+METHOD int list_freq {
+	struct clknode		*clk;
+	uint64_t		*freq;
+	int			*freq_count;
+};
+
 #
 # Recalculate frequency
 #     req - in/out recalulated frequency