[ltp] Thinkpad R40 2722: various CPUFREQ troubles

Alexander Gran linux-thinkpad@linux-thinkpad.org
Thu, 11 Dec 2003 14:42:48 +0100

Hash: SHA1

> * I Can't clock the machine at 1500 MHz when disconnected from external
> power. I know IBM wants to conserve battery power here. BUT I DON'T
> CARE. A useless (slow) system is worse than one running two hours less.
> Does this depend on BIOS settings? I think I tried everything possible,
> but never got past 600 MHz.

Which kernel do you use?
With a recent one, it should be no problem to get it to 1500Mzh. Mine does.

> * The system time runs slow. Order of magnitude is about 5 minutes slow
> per hour of operation. This doesn't seem to occur when it is turned off.
> I have to ntpdate several times a day. :-(  CPU frequency doesn't seem
> to have any influence. Time is lost at about the same speed no matter if
> 1500 or 150 MHz. Google says ACPI will fix this (and it does), but with
> ACPI the battery status doesn't work any more.

huh. strange.

> * Strange message in the syslog (appears once, some minutes after
> booting):
> | Losing too many ticks!
> | TSC cannot be used as a timesource. (Are you running with SpeedStep?)
> | Falling back to a sane timesource.

This seems to be related to your 2. problem.

> The answer to that question is probably "yes". The fallback timesource
> obviously isn't more sane either, because it's still wrong :-(

Have you configured something strange in the kernel regarding rtc?

> Pentium M CPU, Linux 2.6-test9 kernel with the CPUFREQ stuff, APM mode,
> acpi=3Doff (you know, the battery).

Ahh. perhaps post the configuration somewhere.

> BIOS settings: CPU frequency is set to "fixed max". (But still the CPU
> runs at 600 instead of 1500.)

This may be due to cpufreq which controls the spped.

> Enabling or disabling SpeedStep in the BIOS doesn't make any difference
> whatsoever. CPUFREQ happily changes frequency in both modes, the system
> time is slow in both.

Yes. you need to change the speed via cpufreq. consider perhaps cpufreqd


=2D --=20
Some operating systems are called `user friendly',
	Linux however is `expert friendly'.
Encrypted Mails welcome.
PGP-Key at http://zodiac.dnsalias.org/misc/pgpkey.asc | Key-ID: 0x6D7DD291
Version: GnuPG v1.2.3 (GNU/Linux)