From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-iw0-f170.google.com (mail-iw0-f170.google.com [209.85.214.170]) by ozlabs.org (Postfix) with ESMTP id 16CEDB6EE8 for ; Tue, 7 Dec 2010 05:25:51 +1100 (EST) Received: by iwn2 with SMTP id 2so40267iwn.15 for ; Mon, 06 Dec 2010 10:25:50 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1291561537-1943-1-git-send-email-maz@misterjones.org> References: <1291561537-1943-1-git-send-email-maz@misterjones.org> Date: Mon, 6 Dec 2010 12:25:49 -0600 Message-ID: Subject: Re: [PATCH] Make auto-loading of therm_pm72 possible From: kevin diggs To: Marc Zyngier Content-Type: text/plain; charset=ISO-8859-1 Cc: Linux PPC Development List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, On a sort of related issue, if anyone out there has a PowerMac7,3 (dual 2.5 GHz 970Fx, PCI-X), I would appreciate it if you could do me a favor. I think this therm_pm72 thing creates the sysfs temperature and voltage attributes for the cpus. I noticed on my machine that if I use the cpufreq driver for this thing the frequencies were like 2.0 and 2.5. The problem is that the cpu voltages were something like 1.25 and 1.37 respectively. At 1.37 and 2.5 GHz, cpu 1 would zoom to 110+ under load. When I finally managed to get a compiler built that could build a kernel past 2.6.28, I removed the cpufreq driver. Now this thing runs at 2.5 GHz all the time. Under load cpu1 tops out at like 74 ish. I eventually noticed that the voltage was 1.25. Huh? I thought this voltage scaling business used the high voltage for the high frequency. How can this thing be running at its high speed at the lower voltage??? Can someone please confirm this behavior on a different 7,3? I did get this thing off of ebay and might have myself a franken G5? Thanks! kevin P.S.: I also don't get the 2.0 GHz low speed? I thought with the FX the speed would be 2.5 / 2 or 1.25? Does this beast NOT use the FX's frequency scaling capabilities?