From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Lezcano Subject: Disabling power management firmware decisions Date: Thu, 19 Mar 2015 14:33:34 +0100 Message-ID: <550AD02E.2080507@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-wg0-f53.google.com ([74.125.82.53]:35699 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751530AbbCSNdi (ORCPT ); Thu, 19 Mar 2015 09:33:38 -0400 Received: by wgdm6 with SMTP id m6so62566249wgd.2 for ; Thu, 19 Mar 2015 06:33:37 -0700 (PDT) Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: "Rafael J. Wysocki" , Len Brown , Linux PM mailing list Hi, I would like to do some experiments with the x86 platform but I am=20 facing one big issue. When I use the rapl register to measure the energy consumption with=20 turbostat and another tool written by me. I see no differences between=20 my kernel changes while using the idlestat tool, I see big differences=20 in the idle state durations with the traces. I remember on x86 the firmware overrides all kernel decisions to do the= =20 power management. So I assume, it is possible my changes are not=20 measurable because of that. Is there a way to tell the firmware to stop overriding the kernel=20 decisions in order to let the kernel handle idle/dvfs on its own ? Thanks -- Daniel --=20 Linaro.org =E2=94=82 Open source software fo= r ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog