mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
58 lines
1.9 KiB
58 lines
1.9 KiB
* Rockchip RK3126/RK3128 Clock and Reset Unit |
|
|
|
The RK3126/RK3128 clock controller generates and supplies clock to various |
|
controllers within the SoC and also implements a reset controller for SoC |
|
peripherals. |
|
|
|
Required Properties: |
|
|
|
- compatible: should be "rockchip,rk3126-cru" or "rockchip,rk3128-cru" |
|
"rockchip,rk3126-cru" - controller compatible with RK3126 SoC. |
|
"rockchip,rk3128-cru" - controller compatible with RK3128 SoC. |
|
- reg: physical base address of the controller and length of memory mapped |
|
region. |
|
- #clock-cells: should be 1. |
|
- #reset-cells: should be 1. |
|
|
|
Optional Properties: |
|
|
|
- rockchip,grf: phandle to the syscon managing the "general register files" |
|
If missing pll rates are not changeable, due to the missing pll lock status. |
|
|
|
Each clock is assigned an identifier and client nodes can use this identifier |
|
to specify the clock which they consume. All available clocks are defined as |
|
preprocessor macros in the dt-bindings/clock/rk3128-cru.h headers and can be |
|
used in device tree sources. Similar macros exist for the reset sources in |
|
these files. |
|
|
|
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: |
|
- "xin24m" - crystal input - required, |
|
- "ext_i2s" - external I2S clock - optional, |
|
- "gmac_clkin" - external GMAC clock - optional |
|
|
|
Example: Clock controller node: |
|
|
|
cru: cru@20000000 { |
|
compatible = "rockchip,rk3128-cru"; |
|
reg = <0x20000000 0x1000>; |
|
rockchip,grf = <&grf>; |
|
|
|
#clock-cells = <1>; |
|
#reset-cells = <1>; |
|
}; |
|
|
|
Example: UART controller node that consumes the clock generated by the clock |
|
controller: |
|
|
|
uart2: serial@20068000 { |
|
compatible = "rockchip,serial"; |
|
reg = <0x20068000 0x100>; |
|
interrupts = <GIC_SPI 22 IRQ_TYPE_LEVEL_HIGH>; |
|
clock-frequency = <24000000>; |
|
clocks = <&cru SCLK_UART2>, <&cru PCLK_UART2>; |
|
clock-names = "sclk_uart", "pclk_uart"; |
|
};
|
|
|