ubuntu-linux-kernel/Documentation/devicetree/bindings/clock/samsung,s5pv210-clock.txt

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* Samsung S5P6442/S5PC110/S5PV210 Clock Controller
Samsung S5P6442, S5PC110 and S5PV210 SoCs contain integrated clock
controller, which generates and supplies clock to various controllers
within the SoC.
Required Properties:
- compatible: should be one of following:
- "samsung,s5pv210-clock" : for clock controller of Samsung
S5PC110/S5PV210 SoCs,
- "samsung,s5p6442-clock" : for clock controller of Samsung
S5P6442 SoC.
- reg: physical base address of the controller and length of memory mapped
region.
- #clock-cells: should be 1.
All available clocks are defined as preprocessor macros in
dt-bindings/clock/s5pv210.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:
- "xxti": external crystal oscillator connected to XXTI and XXTO pins of
the SoC,
- "xusbxti": external crystal oscillator connected to XUSBXTI and XUSBXTO
pins of the SoC,
A subset of above clocks available on given board shall be specified in
board device tree, including the system base clock, as selected by XOM[0]
pin of the SoC. Refer to generic fixed rate clock bindings
documentation[1] for more information how to specify these clocks.
[1] Documentation/devicetree/bindings/clock/fixed-clock.txt
Example: Clock controller node:
clock: clock-controller@7e00f000 {
compatible = "samsung,s5pv210-clock";
reg = <0x7e00f000 0x1000>;
#clock-cells = <1>;
};
Example: Required external clocks:
xxti: clock-xxti {
compatible = "fixed-clock";
clock-output-names = "xxti";
clock-frequency = <24000000>;
#clock-cells = <0>;
};
xusbxti: clock-xusbxti {
compatible = "fixed-clock";
clock-output-names = "xusbxti";
clock-frequency = <24000000>;
#clock-cells = <0>;
};
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):
uart0: serial@e2900000 {
compatible = "samsung,s5pv210-uart";
reg = <0xe2900000 0x400>;
interrupt-parent = <&vic1>;
interrupts = <10>;
clock-names = "uart", "clk_uart_baud0",
"clk_uart_baud1";
clocks = <&clocks UART0>, <&clocks UART0>,
<&clocks SCLK_UART0>;
};