Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | * NXP LPC1850 Clock Control Unit (CCU) |
| 2 | |
| 3 | Each CGU base clock has several clock branches which can be turned on |
| 4 | or off independently by the Clock Control Units CCU1 or CCU2. The |
| 5 | branch clocks are distributed between CCU1 and CCU2. |
| 6 | |
| 7 | - Above text taken from NXP LPC1850 User Manual. |
| 8 | |
| 9 | This binding uses the common clock binding: |
| 10 | Documentation/devicetree/bindings/clock/clock-bindings.txt |
| 11 | |
| 12 | Required properties: |
| 13 | - compatible: |
| 14 | Should be "nxp,lpc1850-ccu" |
| 15 | - reg: |
| 16 | Shall define the base and range of the address space |
| 17 | containing clock control registers |
| 18 | - #clock-cells: |
| 19 | Shall have value <1>. The permitted clock-specifier values |
| 20 | are the branch clock names defined in table below. |
| 21 | - clocks: |
| 22 | Shall contain a list of phandles for the base clocks routed |
| 23 | from the CGU to the specific CCU. See mapping of base clocks |
| 24 | and CCU in table below. |
| 25 | - clock-names: |
| 26 | Shall contain a list of names for the base clock routed |
| 27 | from the CGU to the specific CCU. Valid CCU clock names: |
| 28 | "base_usb0_clk", "base_periph_clk", "base_usb1_clk", |
| 29 | "base_cpu_clk", "base_spifi_clk", "base_spi_clk", |
| 30 | "base_apb1_clk", "base_apb3_clk", "base_adchs_clk", |
| 31 | "base_sdio_clk", "base_ssp0_clk", "base_ssp1_clk", |
| 32 | "base_uart0_clk", "base_uart1_clk", "base_uart2_clk", |
| 33 | "base_uart3_clk", "base_audio_clk" |
| 34 | |
| 35 | Which branch clocks that are available on the CCU depends on the |
| 36 | specific LPC part. Check the user manual for your specific part. |
| 37 | |
| 38 | A list of CCU clocks can be found in dt-bindings/clock/lpc18xx-ccu.h. |
| 39 | |
| 40 | Example board file: |
| 41 | |
| 42 | soc { |
| 43 | ccu1: clock-controller@40051000 { |
| 44 | compatible = "nxp,lpc1850-ccu"; |
| 45 | reg = <0x40051000 0x1000>; |
| 46 | #clock-cells = <1>; |
| 47 | clocks = <&cgu BASE_APB3_CLK>, <&cgu BASE_APB1_CLK>, |
| 48 | <&cgu BASE_SPIFI_CLK>, <&cgu BASE_CPU_CLK>, |
| 49 | <&cgu BASE_PERIPH_CLK>, <&cgu BASE_USB0_CLK>, |
| 50 | <&cgu BASE_USB1_CLK>, <&cgu BASE_SPI_CLK>; |
| 51 | clock-names = "base_apb3_clk", "base_apb1_clk", |
| 52 | "base_spifi_clk", "base_cpu_clk", |
| 53 | "base_periph_clk", "base_usb0_clk", |
| 54 | "base_usb1_clk", "base_spi_clk"; |
| 55 | }; |
| 56 | |
| 57 | ccu2: clock-controller@40052000 { |
| 58 | compatible = "nxp,lpc1850-ccu"; |
| 59 | reg = <0x40052000 0x1000>; |
| 60 | #clock-cells = <1>; |
| 61 | clocks = <&cgu BASE_AUDIO_CLK>, <&cgu BASE_UART3_CLK>, |
| 62 | <&cgu BASE_UART2_CLK>, <&cgu BASE_UART1_CLK>, |
| 63 | <&cgu BASE_UART0_CLK>, <&cgu BASE_SSP1_CLK>, |
| 64 | <&cgu BASE_SSP0_CLK>, <&cgu BASE_SDIO_CLK>; |
| 65 | clock-names = "base_audio_clk", "base_uart3_clk", |
| 66 | "base_uart2_clk", "base_uart1_clk", |
| 67 | "base_uart0_clk", "base_ssp1_clk", |
| 68 | "base_ssp0_clk", "base_sdio_clk"; |
| 69 | }; |
| 70 | |
| 71 | /* A user of CCU branch clocks */ |
| 72 | uart1: serial@40082000 { |
| 73 | ... |
| 74 | clocks = <&ccu2 CLK_APB0_UART1>, <&ccu1 CLK_CPU_UART1>; |
| 75 | ... |
| 76 | }; |
| 77 | }; |