Enhanced SpeedStep driver available

Alexandre "Sunny" Kovalenko Alex.Kovalenko at verizon.net
Fri Aug 20 20:37:13 PDT 2004

On Wed, 2004-08-18 at 14:29, Toxa wrote:
> On Wed, Aug 18, 2004 at 08:21:41AM +0200, Patrick Hurrelmann wrote:
> > Pentium 4 M is the mobile version of a Pentium 4 and capable of speed step.
> > Pentium M is a complete new processor and not a mobile version of any other. Indeed it is based on the Pentium 3 layout (but only based ;) ).
> > Centrino is no processor at all. Centrino is the name for a hardware bundle:
> >  - Intel Pentium M (no Pentium 4!)
> >  - Intel Chipset (with or without onboard graphic)
> >  - Intel Wireless-LAN adapter
> > If one of this partsis missing on a system it must not be called Centrino (that's Intel politics).
> Thanks for clearing it out for us all, but the fact is that Pentium
> 4 M (not Pentium M from Centrino "toolkit") is capable of SpeedStep
> (Not Enhanced SpeedStep, right?). But freebsd lacks of speedstep support 
> (AFAIK, hw.acpi.cpu_throttle_state plays only with processor C-states,
> which are not SpeedStep),  so I'm womdering if est.ko would do
> something with Pentium 4 M processors.
Ahem... some time last fall I was using CPU throttling on my ThinkPad
560Z (Pentium II 266MHz). Worked nicely in 8 steps (12.5% increments). I
don't know if it was Pentium II specific, but it definitely worked out
of the box on then -CURRENT. CPU states were (and still are) separate
from that. I have since switched to AMD laptop and have to use separate
module (powernow_k7), but I am pretty sure that at least some CPU
throttling was there and was working. Controls, AFAICR, were somewhere
in hw.acpi.cpu space.

Sorry for vague recollections, but maybe they will elicit response from
somebody, who has better grip on the subject.

Alexandre "Sunny" Kovalenko.

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