From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Beglin, Brad R" Subject: bug? acpi p-state + ondemand keeps dropping max freq Date: Tue, 10 Jun 2008 18:40:57 -0400 (EDT) Message-ID: <1559428365.1484491213137657411.JavaMail.root@mail4.gatech.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=m.gmane.org+glkc-cpufreq=m.gmane.org@lists.linux.org.uk To: cpufreq@lists.linux.org.uk >I am also unable to change my max scaling frequency on my Thinkpad T61. >Interestingly enough, I can change the frequency as long as the new value >is less than 1.2 GHz. If I try to set the new max frequency higher than that, >the max scaling frequency file reverts to 1.2GHz. Here is in example: Well, I did a lot more research, and it seems, at least in my case and probably others, that this is a long-time know bug, as detailed here: http://bugzilla.kernel.org/show_bug.cgi?id=7060 http://lkml.org/lkml/2007/1/16/120 http://www.thinkwiki.org/wiki/Problem_with_CPU_frequency_scaling http://forums.lenovo.com/lnv/board/message?board.id=T_Series_Thinkpads&thread.id=7420 However, I can report, as outlined in the Thinkwiki.org article, that adding "processor.ignore_ppc=1" to the kernel boot parameters fixed the problem for me (with kernel 2.6.25-r4). I hope this helps the others who are having the same problem. mp. -- Brad R. Beglin Computational Media Undergraduate Georgia Institute of Technology