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+* Nuvoton NPCM7XX Clock Controller
+
+Nuvoton Poleg BMC NPCM7XX contains an integrated clock controller, which
+generates and supplies clocks to all modules within the BMC.
+
+External clocks:
+
+There are six fixed clocks that are generated outside the BMC. All clocks are of
+a known fixed value that cannot be changed. clk_refclk, clk_mcbypck and
+clk_sysbypck are inputs to the clock controller.
+clk_rg1refck, clk_rg2refck and clk_xin are external clocks suppling the
+network. They are set on the device tree, but not used by the clock module. The
+network devices use them directly.
+Example can be found below.
+
+All available clocks are defined as preprocessor macros in:
+dt-bindings/clock/nuvoton,npcm7xx-clock.h
+and can be reused as DT sources.
+
+Required Properties of clock controller:
+
+ - compatible: "nuvoton,npcm750-clk" : for clock controller of Nuvoton
+ Poleg BMC NPCM750
+
+ - reg: physical base address of the clock controller and length of
+ memory mapped region.
+
+ - #clock-cells: should be 1.
+
+Example: Clock controller node:
+
+ clk: clock-controller@f0801000 {
+ compatible = "nuvoton,npcm750-clk";
+ #clock-cells = <1>;
+ reg = <0xf0801000 0x1000>;
+ clock-names = "refclk", "sysbypck", "mcbypck";
+ clocks = <&clk_refclk>, <&clk_sysbypck>, <&clk_mcbypck>;
+ };
+
+Example: Required external clocks for network:
+
+ /* external reference clock */
+ clk_refclk: clk-refclk {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <25000000>;
+ clock-output-names = "refclk";
+ };
+
+ /* external reference clock for cpu. float in normal operation */
+ clk_sysbypck: clk-sysbypck {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <800000000>;
+ clock-output-names = "sysbypck";
+ };
+
+ /* external reference clock for MC. float in normal operation */
+ clk_mcbypck: clk-mcbypck {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <800000000>;
+ clock-output-names = "mcbypck";
+ };
+
+ /* external clock signal rg1refck, supplied by the phy */
+ clk_rg1refck: clk-rg1refck {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <125000000>;
+ clock-output-names = "clk_rg1refck";
+ };
+
+ /* external clock signal rg2refck, supplied by the phy */
+ clk_rg2refck: clk-rg2refck {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <125000000>;
+ clock-output-names = "clk_rg2refck";
+ };
+
+ clk_xin: clk-xin {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <50000000>;
+ clock-output-names = "clk_xin";
+ };
+
+
+Example: GMAC controller node that consumes two clocks: a generated clk by the
+clock controller and a fixed clock from DT (clk_rg1refck).
+
+ ethernet0: ethernet@f0802000 {
+ compatible = "snps,dwmac";
+ reg = <0xf0802000 0x2000>;
+ interrupts = <0 14 4>;
+ interrupt-names = "macirq";
+ clocks = <&clk_rg1refck>, <&clk NPCM7XX_CLK_AHB>;
+ clock-names = "stmmaceth", "clk_gmac";
+ };