From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756559Ab1GMQpk (ORCPT ); Wed, 13 Jul 2011 12:45:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48449 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756202Ab1GMQpi (ORCPT ); Wed, 13 Jul 2011 12:45:38 -0400 Date: Wed, 13 Jul 2011 12:45:30 -0400 From: Dave Jones To: =?utf-8?B?UmFmYcWC?= Bilski Cc: Axel Lin , linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org Subject: Re: [PATCH] e_powersaver: Underclock checks Message-ID: <20110713164529.GA1652@redhat.com> Mail-Followup-To: Dave Jones , =?utf-8?B?UmFmYcWC?= Bilski , Axel Lin , linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org References: <1310114243.2940.3.camel@phoenix> <4E1B745A.5000802@interia.pl> <4E1B8404.1050909@interia.pl> <20110711232517.GC20367@redhat.com> <4E1C7D96.1030500@interia.pl> <4E1DCA76.7090809@interia.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4E1DCA76.7090809@interia.pl> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 13, 2011 at 05:40:22PM +0100, Rafał Bilski wrote: > > >Some systems are using 1.2GHz@844mV processors running at 600MHz@796mV. > OK. That's strange. It is 1,2GHz system. Can both ACPI p-states and "e_powersaver" > drivers be running at the same time? no > Can BIOS change processor frequencies without > Linux knowing and without p-states driver loaded? yes. Usually via SMI. some laptops do this when switching between power/battery, and/or when overheating. cpufreq usually detects when this happens and logs messages. Dave