[ltp] undervolted T43 does not resume from suspend-to-ram when on battery

[Marcus Obst]

Hi,

two weeks age I undervolted my T43 with the unmodified example kernel
patch (Alternative 1) provieded by

    http://thinkwiki.org/wiki/Pentium_M_undervolting_and_underclocking

My system used to run quite stable even under high load (it survived
multiple kernel and QT4 compilations).

Also the other promised featuers are working:
    - high pitch noise gone
    - battery life prolonged
    - cpu temperature decreasd, especially with high load
      (15K less then before)

Yesterday I tried to wake up my Thinkpad from suspend-to-disk without
AC connected . 
The system came up but screen remained still blank.  Only the ACPI event
for the power button was generated, so I could reboot.

After reboot (still running on battery) system came up but showed
strange error messages about wrong cpu frequency settings.
I inspected /proc/cpuinfo and found a crooked frequency value.  It was
about 377MHz (normally it is the default max value of 1862MHz).
Frequency scaling was not activated at this time.

Then I plugged in AC and rebooted, everything was fine again.

-> It is a reproduceable problem which only happens if laptop is on
   battery.

Anybody seen this before, ideas?

    Best regards from Chemnitz/Germany!
    Marcus Obst

-- 
Marcus Obst <maob@hrz.tu-chemnitz.de>