From mboxrd@z Thu Jan 1 00:00:00 1970 From: Punit Agrawal Subject: [PATCH 1/9] devicetree: bindings: Add optional dynamic-power-coefficient property Date: Wed, 22 Jul 2015 15:02:35 +0100 Message-ID: <1437573763-6525-2-git-send-email-punit.agrawal@arm.com> References: <1437573763-6525-1-git-send-email-punit.agrawal@arm.com> Return-path: In-Reply-To: <1437573763-6525-1-git-send-email-punit.agrawal-5wv7dgnIgG8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Punit Agrawal , lm-sensors-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, viresh.kumar-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, Rob Herring , Mark Rutland List-Id: devicetree@vger.kernel.org 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 dynamic-power-coefficient property represents an indicative running time dynamic power coefficient in fundamental 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 Cc: Rob Herring Cc: Mark Rutland --- Documentation/devicetree/bindings/arm/cpus.txt | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt index d6b794c..c32bfac 100644 --- a/Documentation/devicetree/bindings/arm/cpus.txt +++ b/Documentation/devicetree/bindings/arm/cpus.txt @@ -239,6 +239,21 @@ 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 an indicative + running time dynamic power coefficient in + fundamental units of mW/MHz/uVolt^2. + + The dynamic energy consumption of the CPU + is proportional to the square of the + Voltage (V) and the clock frequency (f). + + 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 { -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html