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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>;
+ };
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+// SPDX-License-Identifier: GPL-2.0+
+//
+// Device Tree binding constants for Actions Semi S900 Clock Management Unit
+//
+// Copyright (c) 2014 Actions Semi Inc.
+// Copyright (c) 2018 Linaro Ltd.
+
+#ifndef __DT_BINDINGS_CLOCK_S900_CMU_H
+#define __DT_BINDINGS_CLOCK_S900_CMU_H
+
+#define CLK_NONE 0
+
+/* fixed rate clocks */
+#define CLK_LOSC 1
+#define CLK_HOSC 2
+
+/* pll clocks */
+#define CLK_CORE_PLL 3
+#define CLK_DEV_PLL 4
+#define CLK_DDR_PLL 5
+#define CLK_NAND_PLL 6
+#define CLK_DISPLAY_PLL 7
+#define CLK_DSI_PLL 8
+#define CLK_ASSIST_PLL 9
+#define CLK_AUDIO_PLL 10
+
+/* system clock */
+#define CLK_CPU 15
+#define CLK_DEV 16
+#define CLK_NOC 17
+#define CLK_NOC_MUX 18
+#define CLK_NOC_DIV 19
+#define CLK_AHB 20
+#define CLK_APB 21
+#define CLK_DMAC 22
+
+/* peripheral device clock */
+#define CLK_GPIO 23
+
+#define CLK_BISP 24
+#define CLK_CSI0 25
+#define CLK_CSI1 26
+
+#define CLK_DE0 27
+#define CLK_DE1 28
+#define CLK_DE2 29
+#define CLK_DE3 30
+#define CLK_DSI 32
+
+#define CLK_GPU 33
+#define CLK_GPU_CORE 34
+#define CLK_GPU_MEM 35
+#define CLK_GPU_SYS 36
+
+#define CLK_HDE 37
+#define CLK_I2C0 38
+#define CLK_I2C1 39
+#define CLK_I2C2 40
+#define CLK_I2C3 41
+#define CLK_I2C4 42
+#define CLK_I2C5 43
+#define CLK_I2SRX 44
+#define CLK_I2STX 45
+#define CLK_IMX 46
+#define CLK_LCD 47
+#define CLK_NAND0 48
+#define CLK_NAND1 49
+#define CLK_PWM0 50
+#define CLK_PWM1 51
+#define CLK_PWM2 52
+#define CLK_PWM3 53
+#define CLK_PWM4 54
+#define CLK_PWM5 55
+#define CLK_SD0 56
+#define CLK_SD1 57
+#define CLK_SD2 58
+#define CLK_SD3 59
+#define CLK_SENSOR 60
+#define CLK_SPEED_SENSOR 61
+#define CLK_SPI0 62
+#define CLK_SPI1 63
+#define CLK_SPI2 64
+#define CLK_SPI3 65
+#define CLK_THERMAL_SENSOR 66
+#define CLK_UART0 67
+#define CLK_UART1 68
+#define CLK_UART2 69
+#define CLK_UART3 70
+#define CLK_UART4 71
+#define CLK_UART5 72
+#define CLK_UART6 73
+#define CLK_VCE 74
+#define CLK_VDE 75
+
+#define CLK_USB3_480MPLL0 76
+#define CLK_USB3_480MPHY0 77
+#define CLK_USB3_5GPHY 78
+#define CLK_USB3_CCE 79
+#define CLK_USB3_MAC 80
+
+#define CLK_TIMER 83
+
+#define CLK_HDMI_AUDIO 84
+
+#define CLK_24M 85
+
+#define CLK_EDP 86
+
+#define CLK_24M_EDP 87
+#define CLK_EDP_PLL 88
+#define CLK_EDP_LINK 89
+
+#define CLK_USB2H0_PLLEN 90
+#define CLK_USB2H0_PHY 91
+#define CLK_USB2H0_CCE 92
+#define CLK_USB2H1_PLLEN 93
+#define CLK_USB2H1_PHY 94
+#define CLK_USB2H1_CCE 95
+
+#define CLK_DDR0 96
+#define CLK_DDR1 97
+#define CLK_DMM 98
+
+#define CLK_ETH_MAC 99
+#define CLK_RMII_REF 100
+
+#define CLK_NR_CLKS (CLK_RMII_REF + 1)
+
+#endif /* __DT_BINDINGS_CLOCK_S900_CMU_H */