[ltp] Temperature problem with my T41p

[Damien Challet]

On Friday 02 December 2005 16:36, Mcskasi Csaba wrote:
> On Fri, 02 Dec 2005 16:21:55 +0100, Bobby <bobby001@gmail.com> wrote:
> > I don't have /sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages on my
> > debian, how did you get it ?
>
> Here is a howto how to undervolt your cpu / getting the
> scaling_voltages-interface:
> http://www.thinkwiki.org/wiki/Pentium_M_undervolting_and_underclocking
>
> However, i could not manage to get undervolting to work with a patched
> vanilla kernel. I can't change the values in the scaling_voltage
> interface. Any clues? Thx.

Here is the script I run in /etc/init.d. Note that your minimum voltages might 
be higher (or smaller) than mine. centrino-voltages.diff patch, with vanilla 
kernel 2.6.14.2, Banias 1.7GHz.

#!/bin/sh
#
# Please copy this file in /etc/init.d and make it executable

case $1 in
  start)
    echo -n "Reducing Pentium M voltages "
# frequency voltage
    echo 600000 700 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 800000 850 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1000000 900 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1200000 1000 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1400000 1100 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1700000 1196 >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo "done."
    exit 0
    ;;

  restart|reload|force-reload)
    set -e
    echo -n "Restarting Pentium M voltage reduction"
    $0 stop > /dev/null
    $0 start > /dev/null
    echo "done."

    exit 0
    ;;

  stop)

# frequency voltage
    echo -n "Restoring Pentium M voltages ... "
    echo 600000 956  >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 800000 1004  >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1000000 1116  >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1200000 1228  >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1400000 1308  >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo 1700000 1484  >/sys/devices/system/cpu/cpu0/cpufreq/scaling_voltages
    echo "done."
    exit 0;
    ;;

  *)
      echo "Usage: $0 {stop|start|restart|reload|force-reload}" >&2
      exit 1
    ;;
esac