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+* Rockchip RK3399 Clock and Reset Unit
+
+The RK3399 clock controller generates and supplies clock to various
+controllers within the SoC and also implements a reset controller for SoC
+peripherals.
+
+Required Properties:
+
+- compatible: PMU for CRU should be "rockchip,rk3399-pmucru"
+- compatible: CRU should be "rockchip,rk3399-cru"
+- reg: physical base address of the controller and length of memory mapped
+ region.
+- #clock-cells: should be 1.
+- #reset-cells: should be 1.
+
+Optional Properties:
+
+- rockchip,grf: phandle to the syscon managing the "general register files".
+ It is used for GRF muxes, if missing any muxes present in the GRF will not
+ be available.
+
+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 the dt-bindings/clock/rk3399-cru.h headers and can be
+used in device tree sources. Similar macros exist for the reset sources in
+these files.
+
+External clocks:
+
+There are several clocks that are generated outside the SoC. It is expected
+that they are defined using standard clock bindings with following
+clock-output-names:
+ - "xin24m" - crystal input - required,
+ - "xin32k" - rtc clock - optional,
+ - "clkin_gmac" - external GMAC clock - optional,
+ - "clkin_i2s" - external I2S clock - optional,
+ - "pclkin_cif" - external ISP clock - optional,
+ - "clk_usbphy0_480m" - output clock of the pll in the usbphy0
+ - "clk_usbphy1_480m" - output clock of the pll in the usbphy1
+
+Example: Clock controller node:
+
+ pmucru: pmu-clock-controller@ff750000 {
+ compatible = "rockchip,rk3399-pmucru";
+ reg = <0x0 0xff750000 0x0 0x1000>;
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
+
+ cru: clock-controller@ff760000 {
+ compatible = "rockchip,rk3399-cru";
+ reg = <0x0 0xff760000 0x0 0x1000>;
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
+
+Example: UART controller node that consumes the clock generated by the clock
+ controller:
+
+ uart0: serial@ff1a0000 {
+ compatible = "rockchip,rk3399-uart", "snps,dw-apb-uart";
+ reg = <0x0 0xff180000 0x0 0x100>;
+ clocks = <&cru SCLK_UART0>, <&cru PCLK_UART0>;
+ clock-names = "baudclk", "apb_pclk";
+ interrupts = <GIC_SPI 99 IRQ_TYPE_LEVEL_HIGH>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ };