xref: /freebsd/sys/contrib/device-tree/Bindings/clock/samsung,s3c2412-clock.txt (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1*c66ec88fSEmmanuel Vadot* Samsung S3C2412 Clock Controller
2*c66ec88fSEmmanuel Vadot
3*c66ec88fSEmmanuel VadotThe S3C2412 clock controller generates and supplies clock to various controllers
4*c66ec88fSEmmanuel Vadotwithin the SoC. The clock binding described here is applicable to the s3c2412
5*c66ec88fSEmmanuel Vadotand s3c2413 SoCs in the s3c24x family.
6*c66ec88fSEmmanuel Vadot
7*c66ec88fSEmmanuel VadotRequired Properties:
8*c66ec88fSEmmanuel Vadot
9*c66ec88fSEmmanuel Vadot- compatible: should be "samsung,s3c2412-clock"
10*c66ec88fSEmmanuel Vadot- reg: physical base address of the controller and length of memory mapped
11*c66ec88fSEmmanuel Vadot  region.
12*c66ec88fSEmmanuel Vadot- #clock-cells: should be 1.
13*c66ec88fSEmmanuel Vadot
14*c66ec88fSEmmanuel VadotEach clock is assigned an identifier and client nodes can use this identifier
15*c66ec88fSEmmanuel Vadotto specify the clock which they consume. Some of the clocks are available only
16*c66ec88fSEmmanuel Vadoton a particular SoC.
17*c66ec88fSEmmanuel Vadot
18*c66ec88fSEmmanuel VadotAll available clocks are defined as preprocessor macros in
19*c66ec88fSEmmanuel Vadotdt-bindings/clock/s3c2412.h header and can be used in device
20*c66ec88fSEmmanuel Vadottree sources.
21*c66ec88fSEmmanuel Vadot
22*c66ec88fSEmmanuel VadotExternal clocks:
23*c66ec88fSEmmanuel Vadot
24*c66ec88fSEmmanuel VadotThere are several clocks that are generated outside the SoC. It is expected
25*c66ec88fSEmmanuel Vadotthat they are defined using standard clock bindings with following
26*c66ec88fSEmmanuel Vadotclock-output-names:
27*c66ec88fSEmmanuel Vadot - "xti" - crystal input - required,
28*c66ec88fSEmmanuel Vadot - "ext" - external clock source - optional,
29*c66ec88fSEmmanuel Vadot
30*c66ec88fSEmmanuel VadotExample: Clock controller node:
31*c66ec88fSEmmanuel Vadot
32*c66ec88fSEmmanuel Vadot	clocks: clock-controller@4c000000 {
33*c66ec88fSEmmanuel Vadot		compatible = "samsung,s3c2412-clock";
34*c66ec88fSEmmanuel Vadot		reg = <0x4c000000 0x20>;
35*c66ec88fSEmmanuel Vadot		#clock-cells = <1>;
36*c66ec88fSEmmanuel Vadot	};
37*c66ec88fSEmmanuel Vadot
38*c66ec88fSEmmanuel VadotExample: UART controller node that consumes the clock generated by the clock
39*c66ec88fSEmmanuel Vadot  controller (refer to the standard clock bindings for information about
40*c66ec88fSEmmanuel Vadot  "clocks" and "clock-names" properties):
41*c66ec88fSEmmanuel Vadot
42*c66ec88fSEmmanuel Vadot	serial@50004000 {
43*c66ec88fSEmmanuel Vadot		compatible = "samsung,s3c2412-uart";
44*c66ec88fSEmmanuel Vadot		reg = <0x50004000 0x4000>;
45*c66ec88fSEmmanuel Vadot		interrupts = <1 23 3 4>, <1 23 4 4>;
46*c66ec88fSEmmanuel Vadot		clock-names = "uart", "clk_uart_baud2", "clk_uart_baud3";
47*c66ec88fSEmmanuel Vadot		clocks = <&clocks PCLK_UART0>, <&clocks PCLK_UART0>,
48*c66ec88fSEmmanuel Vadot			 <&clocks SCLK_UART>;
49*c66ec88fSEmmanuel Vadot	};
50