xref: /kernel/linux/linux-5.10/Documentation/devicetree/bindings/clock/samsung,s3c2443-clock.txt (revision 8c2ecf20)

* Samsung S3C2443 Clock Controller

The S3C2443 clock controller generates and supplies clock to various controllers
within the SoC. The clock binding described here is applicable to all SoCs in
the s3c24x family starting with the s3c2443.

Required Properties:

- compatible: should be one of the following.
  - "samsung,s3c2416-clock" - controller compatible with S3C2416 SoC.
  - "samsung,s3c2443-clock" - controller compatible with S3C2443 SoC.
  - "samsung,s3c2450-clock" - controller compatible with S3C2450 SoC.
- reg: physical base address of the controller and length of memory mapped
  region.
- #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. Some of the clocks are available only
on a particular SoC.

All available clocks are defined as preprocessor macros in
dt-bindings/clock/s3c2443.h header and can be used in device
tree sources.

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:
 - "xti" - crystal input - required,
 - "ext" - external clock source - optional,
 - "ext_i2s" - external I2S clock - optional,
 - "ext_uart" - external uart clock - optional,

Example: Clock controller node:

	clocks: clock-controller@4c000000 {
		compatible = "samsung,s3c2416-clock";
		reg = <0x4c000000 0x40>;
		#clock-cells = <1>;
	};

Example: UART controller node that consumes the clock generated by the clock
  controller (refer to the standard clock bindings for information about
  "clocks" and "clock-names" properties):

	serial@50004000 {
		compatible = "samsung,s3c2440-uart";
		reg = <0x50004000 0x4000>;
		interrupts = <1 23 3 4>, <1 23 4 4>;
		clock-names = "uart", "clk_uart_baud2",
				"clk_uart_baud3";
		clocks = <&clocks PCLK_UART0>, <&clocks PCLK_UART0>,
				<&clocks SCLK_UART>;
	};