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torvalds
GitHub Repository: torvalds/linux
Path: blob/master/Documentation/devicetree/bindings/cpufreq/nvidia,tegra20-cpufreq.txt
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Binding for NVIDIA Tegra20 CPUFreq
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==================================
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Required properties:
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- clocks: Must contain an entry for the CPU clock.
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See ../clocks/clock-bindings.txt for details.
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- operating-points-v2: See ../bindings/opp/opp-v2.yaml for details.
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- #cooling-cells: Should be 2. See ../thermal/thermal-cooling-devices.yaml for details.
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For each opp entry in 'operating-points-v2' table:
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- opp-supported-hw: Two bitfields indicating:
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On Tegra20:
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1. CPU process ID mask
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2. SoC speedo ID mask
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On Tegra30:
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1. CPU process ID mask
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2. CPU speedo ID mask
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A bitwise AND is performed against these values and if any bit
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matches, the OPP gets enabled.
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- opp-microvolt: CPU voltage triplet.
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Optional properties:
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- cpu-supply: Phandle to the CPU power supply.
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Example:
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regulators {
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cpu_reg: regulator0 {
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regulator-name = "vdd_cpu";
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};
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};
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cpu0_opp_table: opp_table0 {
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compatible = "operating-points-v2";
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opp@456000000 {
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clock-latency-ns = <125000>;
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opp-microvolt = <825000 825000 1125000>;
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opp-supported-hw = <0x03 0x0001>;
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opp-hz = /bits/ 64 <456000000>;
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};
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...
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};
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cpus {
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cpu@0 {
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compatible = "arm,cortex-a9";
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clocks = <&tegra_car TEGRA20_CLK_CCLK>;
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operating-points-v2 = <&cpu0_opp_table>;
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cpu-supply = <&cpu_reg>;
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#cooling-cells = <2>;
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};
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};
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