Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752927Ab0DSNoF (ORCPT ); Mon, 19 Apr 2010 09:44:05 -0400 Received: from va3ehsobe003.messaging.microsoft.com ([216.32.180.13]:25944 "EHLO VA3EHSOBE003.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751558Ab0DSNoD convert rfc822-to-8bit (ORCPT ); Mon, 19 Apr 2010 09:44:03 -0400 X-SpamScore: -11 X-BigFish: VPS-11(zz1432P1418Mzz1202hz31izz32i2a8h43h61h) X-Spam-TCS-SCL: 0:0 X-FB-SS: 5, X-WSS-ID: 0L14M4Y-01-FK3-02 X-M-MSG: From: "Langsdorf, Mark" To: "'joss@debian.org'" CC: "'linux-kernel@vger.kernel.org'" Date: Mon, 19 Apr 2010 06:43:48 -0700 Subject: Athlon L110 CPU and powernow-k8 Thread-Topic: Athlon L110 CPU and powernow-k8 Thread-Index: Acre/G7tcZX5bOQjTye14yU3Lj886wAx9EHw Message-ID: References: <20100418102608.GA29846@a1.tnic> In-Reply-To: <20100418102608.GA29846@a1.tnic> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-Reverse-DNS: unknown Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1709 Lines: 45 > Date: Fri, 16 Apr 2010 22:40:58 +0200 > From: Josselin Mouette > To: linux-kernel@vger.kernel.org > Subject: Athlon L110 CPU and powernow-k8 > X-Mailer: Evolution 2.29.92.1 > Message-ID: <1271450458.6794.33.camel@tomoyo> > > In both cases, the issue is the same: the DSDT table provided by the > BIOS does not include the P-states. Waiting for a hypothetical BIOS > update that would fix this bug requires some faith that I > don't have. It is possible to work around this by compiling the > kernel with a custom DSDT table with appropriate P-states patched > in, however I consider this a developer hack. > > I wonder what is possible to do to support this CPU correctly in the > kernel. The only sane solution I can think of is to hardcode the > P-states for this CPU model in the powernow-k8 driver itself. I think that hard-coding P-states into the PowerNow driver is not a mantainable solution. I don't quite understand why the you think that a custom DSDT as a BIOS hack, but think that adding custom frequencies to the driver itself is acceptable. The last time this issue came up on cpufreq, Dave Jones nixed a general solution to add custom P-states through the driver on the grounds that people would undervolt their systems, causing a lot of screwy, unpredictable behavior. I agreed with his opinion then and I don't see anything in this mesage to change that view. --Mark Langsdorf Operating System Research Center AMD -- 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/