| Message ID | 1447702225-13323-2-git-send-email-punit.agrawal@arm.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On Mon, Nov 16, 2015 at 07:30:23PM +0000, Punit Agrawal wrote: > 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> > Cc: Rob Herring <robh+dt@kernel.org> > Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Rob Herring <robh@kernel.org> > --- > 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 > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, Nov 17, 2015 at 1:00 AM, Punit Agrawal <punit.agrawal@arm.com> wrote: > 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> > Cc: Rob Herring <robh+dt@kernel.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 { Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 {
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> Cc: Rob Herring <robh+dt@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> --- Documentation/devicetree/bindings/arm/cpus.txt | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)