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