From patchwork Tue Nov 17 12:06:21 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 56787 Delivered-To: patch@linaro.org Received: by 10.112.155.196 with SMTP id vy4csp1892027lbb; Tue, 17 Nov 2015 04:07:11 -0800 (PST) X-Received: by 10.68.223.70 with SMTP id qs6mr62229990pbc.109.1447762031231; Tue, 17 Nov 2015 04:07:11 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id fl4si51419249pab.73.2015.11.17.04.07.10; Tue, 17 Nov 2015 04:07:11 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753095AbbKQMHF (ORCPT + 28 others); Tue, 17 Nov 2015 07:07:05 -0500 Received: from fw-tnat.cambridge.arm.com ([217.140.96.140]:25820 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752603AbbKQMHC (ORCPT ); Tue, 17 Nov 2015 07:07:02 -0500 Received: from e105922-lin.cambridge.arm.com (e105922-lin.cambridge.arm.com [10.1.207.164]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with SMTP id tAHC6jhl024980; Tue, 17 Nov 2015 12:06:45 GMT Received: by e105922-lin.cambridge.arm.com (sSMTP sendmail emulation); Tue, 17 Nov 2015 12:06:45 +0000 From: Punit Agrawal To: linux-pm@vger.kernel.org Cc: Punit Agrawal , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, edubezval@gmail.com, dawei.chien@mediatek.com, javi.merino@arm.com, viresh.kumar@linaro.org, rjw@rjwysocki.net, Mark Rutland Subject: [PATCH v5 1/3] devicetree: bindings: Add optional dynamic-power-coefficient property Date: Tue, 17 Nov 2015 12:06:21 +0000 Message-Id: <1447761983-12415-2-git-send-email-punit.agrawal@arm.com> X-Mailer: git-send-email 2.6.2 In-Reply-To: <1447761983-12415-1-git-send-email-punit.agrawal@arm.com> References: <1447761983-12415-1-git-send-email-punit.agrawal@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 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 Acked-by: Rob Herring Reviewed-by: Viresh Kumar Cc: Mark Rutland --- Documentation/devicetree/bindings/arm/cpus.txt | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) -- 2.6.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ 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: + 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 {