dt-bindings: clock: Add Actions S900 clock bindings

Add Actions Semi S900 clock bindings.

Signed-off-by: Manivannan Sadhasivam <[e-mail]>
Acked-by: Rob Herring <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

Documentation/devicetree/bindings/clock/actions,s900-cmu.txt

···
+* 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>;
+        };

include/dt-bindings/clock/actions,s900-cmu.h

···
+// 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 */