p4tcc.c from FreeBSD

[YONETANI Tomokazu]

[CC on Nate Lawson hoping we can hear good news from him]

On Sun, Jul 25, 2004 at 11:50:52AM +0000, Johannes Hofmann wrote:
> This patch adds Pentium 4 Thermal Control Circuit (TCC) support from
> FreeBSD (originally from OpenBSD, I think). 
> It can be used to reduce the CPU speed without ACPI support and might be
> useful on machines where ACPI has problems.
> In my tests it actually slowed things down, but I have no results about
> battery life yet.

Thanks for the patch, but the last time this came up, we were going
to wait for the cpufreq driver to be committed to FreeBSD, IIRC. I'm not
sure about the detail of the cpufreq driver, but I hope it include
support for Enhanced SpeedStep Technology(EST) on Pentium M processors,
which is already implemented in NetBSD:

   http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/arch/i386/i386/est.c

Of course this does not mean I'm against p4tcc.c driver to go into
DragonFly tree as it's already been used in FreeBSD.