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2026-01-21 18:59:54 +08:00
* NXP LPC1850 CREG clocks
The NXP LPC18xx/43xx CREG (Configuration Registers) block contains
control registers for two low speed clocks. One of the clocks is a
32 kHz oscillator driver with power up/down and clock gating. Next
is a fixed divider that creates a 1 kHz clock from the 32 kHz osc.
2026-01-29 22:25:33 +08:00
These clocks are used by the RTC and the Event Router peripherals.
The 32 kHz can also be routed to other peripherals to enable low
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power modes.
This binding uses the common clock binding:
Documentation/devicetree/bindings/clock/clock-bindings.txt
Required properties:
- compatible:
Should be "nxp,lpc1850-creg-clk"
- #clock-cells:
Shall have value <1>.
- clocks:
Shall contain a phandle to the fixed 32 kHz crystal.
The creg-clk node must be a child of the creg syscon node.
The following clocks are available from the clock node.
Clock ID Name
0 1 kHz clock
1 32 kHz Oscillator
Example:
soc {
creg: syscon@40043000 {
compatible = "nxp,lpc1850-creg", "syscon", "simple-mfd";
reg = <0x40043000 0x1000>;
creg_clk: clock-controller {
compatible = "nxp,lpc1850-creg-clk";
clocks = <&xtal32>;
#clock-cells = <1>;
};
...
};
rtc: rtc@40046000 {
...
clocks = <&creg_clk 0>, <&ccu1 CLK_CPU_BUS>;
clock-names = "rtc", "reg";
...
};
};