linux/Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt

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Binding for NVIDIA Tegra20 CPUFreq
==================================
Required properties:
- clocks: Must contain an entry for the CPU clock.
See ../clocks/clock-bindings.txt for details.
- operating-points-v2: See ../bindings/opp/opp.txt for details.
- #cooling-cells: Should be 2. See ../thermal/thermal-cooling-devices.yaml for details.
For each opp entry in 'operating-points-v2' table:
- opp-supported-hw: Two bitfields indicating:
On Tegra20:
1. CPU process ID mask
2. SoC speedo ID mask
On Tegra30:
1. CPU process ID mask
2. CPU speedo ID mask
A bitwise AND is performed against these values and if any bit
matches, the OPP gets enabled.
- opp-microvolt: CPU voltage triplet.
Optional properties:
- cpu-supply: Phandle to the CPU power supply.
Example:
regulators {
cpu_reg: regulator0 {
regulator-name = "vdd_cpu";
};
};
cpu0_opp_table: opp_table0 {
compatible = "operating-points-v2";
opp@456000000 {
clock-latency-ns = <125000>;
opp-microvolt = <825000 825000 1125000>;
opp-supported-hw = <0x03 0x0001>;
opp-hz = /bits/ 64 <456000000>;
};
...
};
cpus {
cpu@0 {
compatible = "arm,cortex-a9";
clocks = <&tegra_car TEGRA20_CLK_CCLK>;
operating-points-v2 = <&cpu0_opp_table>;
cpu-supply = <&cpu_reg>;
#cooling-cells = <2>;
};
};