Kernel-4.18.0-80.el8_amlogic,meson8b-clkc

• Amlogic Meson8, Meson8b and Meson8m2 Clock and Reset Unit

The Amlogic Meson8 / Meson8b / Meson8m2 clock controller generates and
supplies clock to various controllers within the SoC.

Required Properties:

• compatible: must be one of:

  • “amlogic,meson8-clkc” for Meson8 (S802) SoCs
  • “amlogic,meson8b-clkc” for Meson8 (S805) SoCs
  • “amlogic,meson8m2-clkc” for Meson8m2 (S812) SoCs

• reg: it must be composed by two tuples:

  0. physical base address of the xtal register and length of memory
     mapped region.
  1. physical base address of the clock controller and length of memory
     mapped region.

• #clock-cells: should be 1.

• #reset-cells: should be 1.

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/meson8b-clkc.h header and can be
used in device tree sources.

Similarly a preprocessor macro for each reset line is defined in
dt-bindings/reset/amlogic,meson8b-clkc-reset.h (which can be used from the
device tree sources).

Example: Clock controller node:

clkc: clock-controller@c1104000 {
    compatible = "amlogic,meson8b-clkc";
    reg = <0xc1108000 0x4>, <0xc1104000 0x460>;
    #clock-cells = <1>;
    #reset-cells = <1>;
};

Example: UART controller node that consumes the clock generated by the clock
controller:

uart_AO: serial@c81004c0 {
    compatible = "amlogic,meson-uart";
    reg = <0xc81004c0 0x14>;
    interrupts = <0 90 1>;
    clocks = <&clkc CLKID_CLK81>;
};