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78 lines
2.4 KiB
Plaintext
78 lines
2.4 KiB
Plaintext
* Samsung S3C64xx Clock Controller
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The S3C64xx clock controller generates and supplies clock to various controllers
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within the SoC. The clock binding described here is applicable to all SoCs in
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the S3C64xx family.
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Required Properties:
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- compatible: should be one of the following.
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- "samsung,s3c6400-clock" - controller compatible with S3C6400 SoC.
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- "samsung,s3c6410-clock" - controller compatible with S3C6410 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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Each clock is assigned an identifier and client nodes can use this identifier
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to specify the clock which they consume. Some of the clocks are available only
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on a particular S3C64xx SoC and this is specified where applicable.
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All available clocks are defined as preprocessor macros in
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dt-bindings/clock/samsung,s3c64xx-clock.h header and can be used in device
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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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- "fin_pll" - PLL input clock (xtal/extclk) - required,
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- "xusbxti" - USB xtal - required,
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- "iiscdclk0" - I2S0 codec clock - optional,
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- "iiscdclk1" - I2S1 codec clock - optional,
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- "iiscdclk2" - I2S2 codec clock - optional,
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- "pcmcdclk0" - PCM0 codec clock - optional,
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- "pcmcdclk1" - PCM1 codec clock - optional, only S3C6410.
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Example: Clock controller node:
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clock: clock-controller@7e00f000 {
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compatible = "samsung,s3c6410-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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fin_pll: clock-fin-pll {
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compatible = "fixed-clock";
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clock-output-names = "fin_pll";
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clock-frequency = <12000000>;
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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 = <48000000>;
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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@7f005000 {
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compatible = "samsung,s3c6400-uart";
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reg = <0x7f005000 0x100>;
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interrupt-parent = <&vic1>;
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interrupts = <5>;
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clock-names = "uart", "clk_uart_baud2",
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"clk_uart_baud3";
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clocks = <&clock PCLK_UART0>, <&clocks PCLK_UART0>,
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<&clock SCLK_UART>;
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status = "disabled";
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};
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