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/opp/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>;
};
};