From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267887AbUGWSy2 (ORCPT ); Fri, 23 Jul 2004 14:54:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267888AbUGWSy2 (ORCPT ); Fri, 23 Jul 2004 14:54:28 -0400 Received: from ms01.sssup.it ([193.205.80.99]:34971 "EHLO sssup.it") by vger.kernel.org with ESMTP id S267887AbUGWSy0 (ORCPT ); Fri, 23 Jul 2004 14:54:26 -0400 Message-ID: <41015EEF.3070602@sssup.it> Date: Fri, 23 Jul 2004 20:54:39 +0200 From: Riccardo Vestrini User-Agent: Mozilla Thunderbird 0.7.1 (X11/20040719) X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: is it really better speedstep-ich vs. p4-clockmod cpufreq driver? X-Enigmail-Version: 0.84.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org it seems that speedstep-ich and acpi cpufreq driver have only two usable clock frequencies, while p4-clockmod has eight my cpu is: Intel Mobile Intel(R) Pentium(R) 4 CPU 3.06GHz stepping 09 last 2.6 kernel I tried (2.6.7) has introduced a warning while loading p4-clockmod module: p4-clockmod: P4/Xeon(TM) CPU On-Demand Clock Modulation available p4-clockmod: Warning: Pentium 4-M detected. The speedstep-ich or acpi cpufreq modules offer voltage scaling in addition of frequency scaling. You should use either one instead of p4-clockmod, if possible. so I immediatly switched to speedstep-ich discovering that: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 3066590 1599960 while with p4-clockmod I have: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 383323 766647 1149971 1533295 1916618 2299942 2683266 3066590 using acpi driver gives a message: cpufreq: CPU0 - ACPI performance management activated. cpufreq: P0: 3059 MHz, 24000 mW, 100 uS cpufreq: *P1: 1596 MHz, 12000 mW, 100 uS but: $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 3059000 1596000 i do not know what driver is supposed to be better and why speedstep-ich driver has only two frequencies thank you -- Riccardo Vestrini