Enhanced SpeedStep driver available

Vladimir Grebenschikov vova at fbsd.ru
Mon Aug 30 06:22:21 PDT 2004

On Mon, 2004-08-16 at 08:06 -0700, Colin Percival wrote:
>   Thanks to everyone who has been sending me data about their
> processors (and in particular, the 90nm versions), I now have
> a first draft of a Enhanced SpeedStep driver available.  For
> people with the appropriate processors (Pentium M only), this
> makes it possible to adjust the cpu frequency via a new sysctl
> (hw.est_curfreq), and have the cpu voltage adjusted at the
> same time.
>   I've also put together a very simple control daemon which
> reads kern.cp_time every second and adjusts the cpu frequency
> based on the fraction of cpu time which is idle.  This increases
> my laptop's battery life by around 40%.
>   All the code is online at
> http://www.daemonology.net/freebsd-est/
>   Assuming I don't hear any major bug reports in the next few
> days, I'll package these into ports and hopefully get them into
> the ports tree in time for 5.3-RELEASE.

Amazing, only issue, flood of speed changing messages in dmesg, please

% cat /usr/ports/sysutils/est/files/patch-est.c-no-flood 
--- est.c.orig  Mon Aug 30 16:53:43 2004
+++ est.c       Mon Aug 30 16:54:38 2004
@@ -505,8 +505,9 @@
                if (f->mhz == 0)
                        return (EOPNOTSUPP);
-               printf("Changing CPU frequency from %d MHz to %d MHz\n",
-                       mhz, mhz_wanted);
+               if (bootverbose)
+                       printf("Changing CPU frequency from %d MHz to %d
+                               mhz, mhz_wanted);
                msr = rdmsr(MSR_PERF_CTL);
                msr = (msr & ~(uint64_t)(0xffff)) |


or like

> Colin Percival

Vladimir B. Grebenchikov
vova at fbsd.ru

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