Re: FreeBSD & SpeedStep
"Kevin Oberman" <[email protected]>
| Newsgroups | gmane.os.freebsd.devel.mobile |
|---|---|
| Message-ID | <[email protected]> |
> Date: Fri, 11 Jun 2004 11:07:49 +0200 > From: Bruno Ducrot <[email protected]> > Sender: [email protected] > > On Fri, Jun 11, 2004 at 11:01:31AM +0200, Frank Altpeter wrote: > > > > Hello! > > > > Bruno Ducrot wrote on 2004-06-11 03:25:07 +0200: > > > On Thu, Jun 10, 2004 at 11:47:01PM +0200, Eduardo Mínguez Pérez wrote: > > > > Hi! > > > > This is my first mail to the list and I want to sorry for my english > > > > (I'm spanish ;D) > > > > My question is... Is speedstep supported by FreeBSD? My notebook is a p4 > > > > mobile (1,7 Ghz) > > > > > > Not yet. > > This answer only applies AFAIK to 4.x FreeBSD versions. 5.2-CURRENT > > does indeed support speedstep technology. > > No. > > > > > # dmesg | grep step > > acpi_cpu: throttling enabled, 8 steps (100% to 12.5%), currently 100.0% > > The processor will be throttled, so frequency will change somehow. But > the voltage (which is the key to speedstep technology) will be the same. Actually, it's not really even that. The clock runs at the same speed, but the duty cycle is reduced to accomplish the "throttling". That allows it to work with little hardware requirements, but means that, if you are testing CPU speed, it will not change. SpeedStep is actually far more sophisticated. It is not in either V4 or V5 at this time, but should be coming to V5 fairly soon. Depends on the time the small number of developers who understand the newbus and ACPI stuff has available. >From the March-April status report: Much of the ACPI project is waiting for architectural changes to be completed. For instance, the cpufreq driver requires newbus attachments for CPUs. Support code for this should be committed at the time of publication. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [email protected] Phone: +1 510 486-8634 _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-mobile To unsubscribe, send any mail to "[email protected]"