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+* Rockchip RK3308 Clock and Reset Unit
+
+The RK3308 clock controller generates and supplies clock to various
+controllers within the SoC and also implements a reset controller for SoC
+peripherals.
+
+Required Properties:
+
+- compatible: CRU should be "rockchip,rk3308-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"
+ If missing, pll rates are not changeable, due to the missing pll lock status.
+
+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/rk3308-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,
+ - "mclk_i2s0_8ch_in", "mclk_i2s1_8ch_in", "mclk_i2s2_8ch_in",
+ "mclk_i2s3_8ch_in", "mclk_i2s0_2ch_in",
+ "mclk_i2s1_2ch_in" - external I2S or SPDIF clock - optional,
+ - "mac_clkin" - external MAC clock - optional
+
+Example: Clock controller node:
+
+ cru: clock-controller@ff500000 {
+ compatible = "rockchip,rk3308-cru";
+ reg = <0x0 0xff500000 0x0 0x1000>;
+ rockchip,grf = <&grf>;
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
+
+Example: UART controller node that consumes the clock generated by the clock
+ controller:
+
+ uart0: serial@ff0a0000 {
+ compatible = "rockchip,rk3308-uart", "snps,dw-apb-uart";
+ reg = <0x0 0xff0a0000 0x0 0x100>;
+ interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&cru SCLK_UART0>, <&cru PCLK_UART0>;
+ clock-names = "baudclk", "apb_pclk";
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ status = "disabled";
+ };