Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | * Samsung S3C64xx Clock Controller |
| 2 | |
| 3 | The S3C64xx clock controller generates and supplies clock to various controllers |
| 4 | within the SoC. The clock binding described here is applicable to all SoCs in |
| 5 | the S3C64xx family. |
| 6 | |
| 7 | Required Properties: |
| 8 | |
| 9 | - compatible: should be one of the following. |
| 10 | - "samsung,s3c6400-clock" - controller compatible with S3C6400 SoC. |
| 11 | - "samsung,s3c6410-clock" - controller compatible with S3C6410 SoC. |
| 12 | |
| 13 | - reg: physical base address of the controller and length of memory mapped |
| 14 | region. |
| 15 | |
| 16 | - #clock-cells: should be 1. |
| 17 | |
| 18 | Each clock is assigned an identifier and client nodes can use this identifier |
| 19 | to specify the clock which they consume. Some of the clocks are available only |
| 20 | on a particular S3C64xx SoC and this is specified where applicable. |
| 21 | |
| 22 | All available clocks are defined as preprocessor macros in |
| 23 | dt-bindings/clock/samsung,s3c64xx-clock.h header and can be used in device |
| 24 | tree sources. |
| 25 | |
| 26 | External clocks: |
| 27 | |
| 28 | There are several clocks that are generated outside the SoC. It is expected |
| 29 | that they are defined using standard clock bindings with following |
| 30 | clock-output-names: |
| 31 | - "fin_pll" - PLL input clock (xtal/extclk) - required, |
| 32 | - "xusbxti" - USB xtal - required, |
| 33 | - "iiscdclk0" - I2S0 codec clock - optional, |
| 34 | - "iiscdclk1" - I2S1 codec clock - optional, |
| 35 | - "iiscdclk2" - I2S2 codec clock - optional, |
| 36 | - "pcmcdclk0" - PCM0 codec clock - optional, |
| 37 | - "pcmcdclk1" - PCM1 codec clock - optional, only S3C6410. |
| 38 | |
| 39 | Example: Clock controller node: |
| 40 | |
| 41 | clock: clock-controller@7e00f000 { |
| 42 | compatible = "samsung,s3c6410-clock"; |
| 43 | reg = <0x7e00f000 0x1000>; |
| 44 | #clock-cells = <1>; |
| 45 | }; |
| 46 | |
| 47 | Example: Required external clocks: |
| 48 | |
| 49 | fin_pll: clock-fin-pll { |
| 50 | compatible = "fixed-clock"; |
| 51 | clock-output-names = "fin_pll"; |
| 52 | clock-frequency = <12000000>; |
| 53 | #clock-cells = <0>; |
| 54 | }; |
| 55 | |
| 56 | xusbxti: clock-xusbxti { |
| 57 | compatible = "fixed-clock"; |
| 58 | clock-output-names = "xusbxti"; |
| 59 | clock-frequency = <48000000>; |
| 60 | #clock-cells = <0>; |
| 61 | }; |
| 62 | |
| 63 | Example: UART controller node that consumes the clock generated by the clock |
| 64 | controller (refer to the standard clock bindings for information about |
| 65 | "clocks" and "clock-names" properties): |
| 66 | |
| 67 | uart0: serial@7f005000 { |
| 68 | compatible = "samsung,s3c6400-uart"; |
| 69 | reg = <0x7f005000 0x100>; |
| 70 | interrupt-parent = <&vic1>; |
| 71 | interrupts = <5>; |
| 72 | clock-names = "uart", "clk_uart_baud2", |
| 73 | "clk_uart_baud3"; |
| 74 | clocks = <&clock PCLK_UART0>, <&clocks PCLK_UART0>, |
| 75 | <&clock SCLK_UART>; |
| 76 | }; |