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+* Actions S900 Clock Management Unit (CMU)
+
+The Actions S900 clock management unit generates and supplies clock to various
+controllers within the SoC. The clock binding described here is applicable to
+S900 SoC.
+
+Required Properties:
+
+- compatible: should be "actions,s900-cmu"
+- reg: physical base address of the controller and length of memory mapped
+  region.
+- clocks: Reference to the parent clocks ("hosc", "losc")
+- #clock-cells: should be 1.
+
+Each clock is assigned an identifier, and client nodes can use this identifier
+to specify the clock which they consume.
+
+All available clocks are defined as preprocessor macros in
+dt-bindings/clock/actions,s900-cmu.h header and can be used in device
+tree sources.
+
+External clocks:
+
+The hosc clock used as input for the plls is generated outside the SoC. It is
+expected that it is defined using standard clock bindings as "hosc".
+
+Actions S900 CMU also requires one more clock:
+ - "losc" - internal low frequency oscillator
+
+Example: Clock Management Unit node:
+
+        cmu: clock-controller@e0160000 {
+                compatible = "actions,s900-cmu";
+                reg = <0x0 0xe0160000 0x0 0x1000>;
+                clocks = <&hosc>, <&losc>;
+                #clock-cells = <1>;
+        };
+
+Example: UART controller node that consumes clock generated by the clock
+management unit:
+
+        uart: serial@e012a000 {
+                compatible = "actions,s900-uart", "actions,owl-uart";
+                reg = <0x0 0xe012a000 0x0 0x2000>;
+                interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+                clocks = <&cmu CLK_UART5>;
+        };