linux/Documentation/devicetree/bindings/cpufreq/arm_big_little_dt.txt

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Generic ARM big LITTLE cpufreq driver's DT glue
-----------------------------------------------
This is DT specific glue layer for generic cpufreq driver for big LITTLE
systems.
Both required and optional properties listed below must be defined
under node /cpus/cpu@x. Where x is the first cpu inside a cluster.
FIXME: Cpus should boot in the order specified in DT and all cpus for a cluster
must be present contiguously. Generic DT driver will check only node 'x' for
cpu:x.
Required properties:
- operating-points: Refer to Documentation/devicetree/bindings/power/opp.txt
for details
Optional properties:
- clock-latency: Specify the possible maximum transition latency for clock,
in unit of nanoseconds.
Examples:
cpus {
#address-cells = <1>;
#size-cells = <0>;
cpu@0 {
compatible = "arm,cortex-a15";
reg = <0>;
next-level-cache = <&L2>;
operating-points = <
/* kHz uV */
792000 1100000
396000 950000
198000 850000
>;
clock-latency = <61036>; /* two CLK32 periods */
};
cpu@1 {
compatible = "arm,cortex-a15";
reg = <1>;
next-level-cache = <&L2>;
};
cpu@100 {
compatible = "arm,cortex-a7";
reg = <100>;
next-level-cache = <&L2>;
operating-points = <
/* kHz uV */
792000 950000
396000 750000
198000 450000
>;
clock-latency = <61036>; /* two CLK32 periods */
};
cpu@101 {
compatible = "arm,cortex-a7";
reg = <101>;
next-level-cache = <&L2>;
};
};