Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754900AbZFGKFw (ORCPT ); Sun, 7 Jun 2009 06:05:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754124AbZFGKFq (ORCPT ); Sun, 7 Jun 2009 06:05:46 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:54464 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753275AbZFGKFp (ORCPT ); Sun, 7 Jun 2009 06:05:45 -0400 Date: Sun, 7 Jun 2009 12:05:41 +0200 From: Ingo Molnar To: "Darrick J. Wong" Cc: Matthew Garrett , Thomas Renninger , linux-kernel , cpufreq@vger.kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH v2] acpi: Fix regression where _PPC is not read at boot even when ignore_ppc=0 Message-ID: <20090607100541.GJ31286@elte.hu> References: <20090428193303.GC6968@plum> <20090428195348.GA8376@srcf.ucam.org> <20090429213930.GE6968@plum> <20090429220037.GA8604@srcf.ucam.org> <20090430072556.GD16737@elte.hu> <20090430095414.GA19462@srcf.ucam.org> <20090430111042.GA12809@elte.hu> <20090430111338.GA21297@srcf.ucam.org> <20090515191219.GH6968@plum> <20090602232108.GG7917@plum> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090602232108.GG7917@plum> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3013 Lines: 79 * Darrick J. Wong wrote: > On Fri, May 15, 2009 at 12:12:19PM -0700, Darrick J. Wong wrote: > > On Thu, Apr 30, 2009 at 12:13:38PM +0100, Matthew Garrett wrote: > > > On Thu, Apr 30, 2009 at 01:10:42PM +0200, Ingo Molnar wrote: > > > > > > > thanks - i've applied this and started testing it. I suspect 1-2 > > > > days of test-time should be enough to see if it breaks this box in > > > > any way. > > > > > > My recollection was that you'd see the machine limited to 1GHz on every > > > boot? > > > > That seems accurate based on my reading of the old thread. > > > > It's been a couple of weeks; has anyone seen any problems? > > Now it's been thirty days since I last heard from anyone. Has the > problem been fixed by some other means? I see no problems on that system here, with the patch below applied. So, as i indicated above, feel free to pursue this angle, there's no objection from me. Thanks, Ingo -------------> >From 244b66ac1fbbe25262a9bcc28179e50930290de8 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Thu, 30 Apr 2009 10:54:14 +0100 Subject: [PATCH] acpi: Fix regression where _PPC is not read at boot even when ignore_ppc=0 Earlier, Ingo Molnar posted a patch to make it so that the kernel would avoid reading _PPC on his broken T60. Unfortunately, it seems that with Thomas Renninger's patch last July to eliminate _PPC evaluations when the processor driver loads, the kernel never actually reads _PPC at all! This is problematic if you happen to boot your non-T60 computer in a state where the BIOS _wants_ _PPC to be something other than zero. So, put the _PPC evaluation back into acpi_processor_get_performance_info if ignore_ppc isn't 1. This second version restores the correct function call, which simplifies the patch. I apologize for the churn and the poor eyesight. Signed-off-by: Darrick J. Wong Cc: "Darrick J. Wong" Cc: Thomas Renninger LKML-Reference: <20090430095414.GA19462@srcf.ucam.org> Signed-off-by: Ingo Molnar --- drivers/acpi/processor_perflib.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c index cafb410..85af717 100644 --- a/drivers/acpi/processor_perflib.c +++ b/drivers/acpi/processor_perflib.c @@ -348,7 +348,11 @@ static int acpi_processor_get_performance_info(struct acpi_processor *pr) if (result) goto update_bios; - return 0; + /* We need to call _PPC once when cpufreq starts */ + if (ignore_ppc != 1) + result = acpi_processor_get_platform_limit(pr); + + return result; /* * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that -- 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/