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: 7636821 X-Patchwork-Delegate: rjw@sisk.pl Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E2D71BF90C for ; Tue, 17 Nov 2015 12:08:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2481E20511 for ; Tue, 17 Nov 2015 12:08:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 60EB520504 for ; Tue, 17 Nov 2015 12:08:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752610AbbKQMHE (ORCPT ); Tue, 17 Nov 2015 07:07:04 -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-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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(+) 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 {