From a772af0b7053c2d728b9ffacdea4f0adee2ca69b Mon Sep 17 00:00:00 2001 From: Punit Agrawal Date: Tue, 17 Nov 2015 12:06:21 +0000 Subject: [PATCH] UPSTREAM: devicetree: bindings: Add optional dynamic-power-coefficient property 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. Change-Id: Ib208ff2f83ee45911e846f940952d765ae8c974e Signed-off-by: Punit Agrawal Acked-by: Rob Herring Reviewed-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki Signed-off-by: Finley Xiao (cherry picked from commit 3be3f8f36e7349006f19c8c8f0d686e98462a993) --- 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 58e240d75169..c352c11bd641 100644 --- a/Documentation/devicetree/bindings/arm/cpus.txt +++ b/Documentation/devicetree/bindings/arm/cpus.txt @@ -243,6 +243,23 @@ 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: + 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 { -- 2.34.1