56 lines
1.2 KiB
Plaintext
56 lines
1.2 KiB
Plaintext
Generic CPU0 cpufreq driver
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It is a generic cpufreq driver for CPU0 frequency management. It
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supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
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systems which share clock and voltage across all CPUs.
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Both required and optional properties listed below must be defined
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under node /cpus/cpu@0.
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Required properties:
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- operating-points: Refer to Documentation/devicetree/bindings/power/opp.txt
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for details
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Optional properties:
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- clock-latency: Specify the possible maximum transition latency for clock,
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in unit of nanoseconds.
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- voltage-tolerance: Specify the CPU voltage tolerance in percentage.
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Examples:
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cpus {
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#address-cells = <1>;
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#size-cells = <0>;
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cpu@0 {
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compatible = "arm,cortex-a9";
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reg = <0>;
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next-level-cache = <&L2>;
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operating-points = <
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/* kHz uV */
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792000 1100000
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396000 950000
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198000 850000
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>;
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transition-latency = <61036>; /* two CLK32 periods */
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};
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cpu@1 {
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compatible = "arm,cortex-a9";
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reg = <1>;
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next-level-cache = <&L2>;
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};
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cpu@2 {
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compatible = "arm,cortex-a9";
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reg = <2>;
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next-level-cache = <&L2>;
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};
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cpu@3 {
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compatible = "arm,cortex-a9";
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reg = <3>;
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next-level-cache = <&L2>;
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};
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};
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