Messages in this thread Patch in this message | | | From | Punit Agrawal <> | Subject | [PATCH v5 1/3] devicetree: bindings: Add optional dynamic-power-coefficient property | Date | Tue, 17 Nov 2015 12:06:21 +0000 |
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The dynamic power consumption of a device is proportional to the square of voltage (V) and the clock frequency (f). It can be expressed as
Pdyn = dynamic-power-coefficient * V^2 * f.
The coefficient represents the running time dynamic power consumption in units of mw/MHz/uVolt^2 and can be used in the above formula to calculate the dynamic power in mW.
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Acked-by: Rob Herring <robh@kernel.org> Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> --- Documentation/devicetree/bindings/arm/cpus.txt | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)
diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt index 3a07a87..6aca64f 100644 --- a/Documentation/devicetree/bindings/arm/cpus.txt +++ b/Documentation/devicetree/bindings/arm/cpus.txt @@ -242,6 +242,23 @@ nodes to be present and contain the properties described below. Definition: Specifies the syscon node controlling the cpu core power domains. + - dynamic-power-coefficient + Usage: optional + Value type: <prop-encoded-array> + Definition: A u32 value that represents the running time dynamic + power coefficient in units of mW/MHz/uVolt^2. The + coefficient can either be calculated from power + measurements or derived by analysis. + + The dynamic power consumption of the CPU is + proportional to the square of the Voltage (V) and + the clock frequency (f). The coefficient is used to + calculate the dynamic power as below - + + Pdyn = dynamic-power-coefficient * V^2 * f + + where voltage is in uV, frequency is in MHz. + Example 1 (dual-cluster big.LITTLE system 32-bit): cpus { -- 2.6.2
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