From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luca Subject: Re: Cpufreq on kernel 2.6.18 Date: Sun, 8 Oct 2006 19:36:37 +0200 Message-ID: <20061008193637.7cf052c7.morpheus@ferrara.linux.it> References: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: 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 Content-Type: text/plain; charset="iso-8859-1" To: "Pallipadi, Venkatesh" Cc: cpufreq@lists.linux.org.uk On Fri, 6 Oct 2006 16:08:22 -0700 "Pallipadi, Venkatesh" wrote: > =20 >=20 > >-----Original Message----- > >From: cpufreq-bounces@lists.linux.org.uk=20 > >[mailto:cpufreq-bounces@lists.linux.org.uk] On Behalf Of Luca > >Sent: Friday, October 06, 2006 1:01 PM > >To: cpufreq@lists.linux.org.uk > >Subject: Cpufreq on kernel 2.6.18 > > > >Hello, > >I just updated the kernel from 2.6.15.2 to 2.6.18 and the=20 > >frequency scaling of my Centrinlo Laptop stopped working=20 > >(keeping the same configuration). > >The dir /sys/devices/system/cpu/cpu0/ is empty and I don't=20 > >know which other tests I could make. > >I also tried to move CONFIG_X86_ACPI_CPUFREQ from builtin to=20 > >module: loading the module does not give any information nor any error. > >I need 2.6.18 for other drivers, so it would be really nice if=20 > >I could solve this problem that seems to be the only driver=20 > >that's not working properly (and my battery would be much happier :) ) > >If you need more informations just tell me. > > >=20 > Can you enable CPU_FREQ_DEBUG in your config and pass "cpufreq.debug=3D3" > in kernel parameter and send in the dmesg log. I found something, and maybe I have to ask excuse, because now it's working= .. Anyway something has changed and that's the reason that fooled me: on my ol= d logs, with the old kernel I had: acpi-cpufreq: CPU0 - ACPI performance management activated. So I focused my attention on the module acpi-cpufreq. Inserting it, even wi= th debug activated (cpufreq.debug=3D3 forgot to pass it at boot, but now se= ems not so important...) doesn't tell anything at all (and doesn't work). I was playing with other modules, and I found that loading the module speed= step-centrino enables cpufreq (even if on kernel log doesn't print anything= ). So something has changed in the software support for my hardware. I'm sorry= for not having understood earlyer. Since I'm writing here, can I kindly as= k you a short explanation on this difference between two different kernels,= on the same hardware. Thanks for the fast answer, Luca. PS: thanks for the work on cpufreq: with the moderm pcs with cpu pull to th= e limit I think it's really useful to be able to force lower frequency, whe= n you don't need all the computeing power. > Thanks, > Venki --=20 .-------------------------------------. -=3D<(=A7 Luca =A7)>=3D- =B0-------------------------------------=B0