Subject: Re: HEADS UP: timecounters (branch simonb-timecounters) merged into
To: Vincent <>
From: Frank Kardel <Frank.Kardel@Acrys.COM>
List: current-users
Date: 06/10/2006 23:01:48
Further debugging with Vincent showed again effects from using TSC on that
platform. Disabling TSC resolved that problem. TSC is not a good timecounter
when it is affected by powersaving or other features (maybe because of busy
waiting on an i/o port?).


Vincent wrote:

> Hi there,
> there is also a strange thing with auich since I compiled the kernel 
> featuring timecounters. Look at the auich0 rate on this excerpt from 
> dmesg:
> timecounter: Timecounter "TSC" frequency 1196183000 Hz quality 800
> WARNING: Callback scheduled before sysmon task queue thread present.
> timecounter: Timecounters tick every 10.000 msec
> timecounter: Timecounter "clockinterrupt" frequency 100 Hz quality 0
> timecounter: selected timecounter "TSC" frequency 1196183000 Hz 
> quality 800
> auich0: measured ac97 link rate at 8378 Hz, will use 48000 Hz
> Normally, it should be around 47 to 48 kHz, as it was before.
> The frequency of the TSC counter is correct, though.
> Vincent