From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dominik Brodowski Subject: Re: [PATCHSET] 0/3 A dynamic cpufreq governor Date: Mon, 27 Oct 2003 19:37:04 +0100 Sender: cpufreq-bounces@www.linux.org.uk Message-ID: <20031027183704.GA4102@brodo.de> References: <88056F38E9E48644A0F562A38C64FB6007796A@scsmsx403.sc.intel.com> <20031027151648.GD4210@brodo.de> <20031027155932.GO28351@poupinou.org> <20031027161905.GP28351@poupinou.org> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: <20031027161905.GP28351@poupinou.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: cpufreq-bounces@www.linux.org.uk Content-Type: text/plain; charset="iso-8859-1" To: Ducrot Bruno Cc: cpufreq@www.linux.org.uk, =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= On Mon, Oct 27, 2003 at 05:19:05PM +0100, Ducrot Bruno wrote: > On Mon, Oct 27, 2003 at 05:06:31PM +0100, M=E5ns Rullg=E5rd wrote: > > Ducrot Bruno writes: > >=20 > > >> >> Is there any way this thing can be made to work on a Pentium 4 = M, > > >> >> using p4-clockmod for frequency changing? > > >> > > > >> > You should prefer the speedstep-ich driver for Pentium 4 M, as l= ong as the > > >> > southbridge on your notebook is from Intel - p4-clockmod doesn't= save you > > >>=20 > > >> The problem is my chipset is SiS 650. > > >>=20 > > > > > > Does the generic acpi P-state driver work? If not, well, nobody ca= n't > >=20 > > I think so, but it only gives two different speeds to choose from, > > 1200 MHz and 2 GHz. p4-clockmod give me speeds from 250 MHz to 2 GHz. > >=20 >=20 > You have then voltage scaling with the acpi driver. > >From my point-of-view, this is better than the p4-clockmod, > the speedstep-ich would give you no more states (if > it can be made to work with SiS southbridges), just that the acpi drive= r > will be a little bit slower (it work by calling some bios functions) > than direct access to IO like speedstep-ich does. > Note that p4-clockmod do *not* regulate voltage. From power comsuption= s > like, if you are at 1200 MHz, but via the acpi driver, you would be > like at 600MHz with the p4-clockmod, and actually it may be possible > that idle loops will be more power conservative with acpi (I am not sur= e for > that one though). Dominik have better words than me to explain that. For more details and calculations, check this thread: http://www.linux.org.uk/mailman/private/cpufreq/2003-September/002495.htm= l Dominik