Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753739Ab0LWSN7 (ORCPT ); Thu, 23 Dec 2010 13:13:59 -0500 Received: from smtp-out.google.com ([74.125.121.67]:9254 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753656Ab0LWSN6 (ORCPT ); Thu, 23 Dec 2010 13:13:58 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=google.com; s=beta; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=Uhu8PnAip8PEo1xLk1JIPhpELx9fz8k6k2r5TDYSVaV1BmNG/7pz0YHwy45e2SFx+D CgV1hu53t1asB6WpGVLw== MIME-Version: 1.0 In-Reply-To: <20101223143859.GA1402@srcf.ucam.org> References: <1293085424-18212-1-git-send-email-youquan.song@intel.com> <1293085424-18212-2-git-send-email-youquan.song@intel.com> <1293085424-18212-3-git-send-email-youquan.song@intel.com> <1293085424-18212-4-git-send-email-youquan.song@intel.com> <1293085424-18212-5-git-send-email-youquan.song@intel.com> <1293085424-18212-6-git-send-email-youquan.song@intel.com> <1293085424-18212-7-git-send-email-youquan.song@intel.com> <20101223105730.GB18363@comet.dominikbrodowski.net> <20101223143859.GA1402@srcf.ucam.org> Date: Thu, 23 Dec 2010 10:13:54 -0800 Message-ID: Subject: Re: [PATCH 6/6] cpufreq: Evaluate P1 before enter turbo mode From: Venkatesh Pallipadi To: Matthew Garrett Cc: Dominik Brodowski , Youquan Song , davej@redhat.com, cpufreq@vger.kernel.org, arjan@linux.intel.com, lenb@kernel.org, suresh.b.siddha@intel.com, kent.liu@intel.com, chaohong.guo@intel.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, Youquan Song Content-Type: text/plain; charset=ISO-8859-1 X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1467 Lines: 38 On Thu, Dec 23, 2010 at 6:38 AM, Matthew Garrett wrote: > On Thu, Dec 23, 2010 at 11:57:30AM +0100, Dominik Brodowski wrote: > >> NACK. First of all, why is it only a "turbo mode" if it's 1000 kHz >> difference? > > I believe that that's how it's supposed to be defined for Intel systems, > but you're right that this doesn't belong in generic code. AMD have > support for enabling/disabling their equivalent functionality through > sysfs - I'd say that copying that interface and using it to limit the > set of p-states provided to the core makes more sense. > If this 1000kHz hack is needed, it should be in acpi-cpufreq driver along with Intel CPU and Turbo mode capability check.. I had a change earlier and I don't think I ever pushed it out. But, it was doing the max freq transition on turbo capable CPUs in 2 steps. Something like: - cpu is in one of the low freqs. - ondemand asks for highest freq. - acpi-cpufreq will check whether the CPU is turbo capable and will only switch to non-turbo peak freq as first step. - If ondemand asks for highest freq again, acpi-cpufreq will then switch to turbo freq. Something like that would probably help the problem here? Thanks, Venki Thanks, Venki -- 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/