Subject: Re: HEADS UP: timecounters (branch simonb-timecounters) merged into
To: Tom Spindler <>
From: Frank Kardel <>
List: current-users
Date: 06/13/2006 20:31:55
Tom Spindler wrote:

>While I haven't tried testing with things after I've farted around
>with adjusting the CPU rate via Enhanced SpeedStep, I now get the
>following curious messages at boot time:
>timecounter: Timecounter "TSC" frequency 1862172710 Hz quality 800
>timecounter: selected timecounter "TSC" frequency 1862172710 Hz quality 800
>WARNING: Callback scheduled before sysmon task queue thread present.
>timecounter: Timecounter "clockinterrupt" frequency 100 Hz quality 0
>auich0: measured ac97 link rate at 10152 Hz, will use 48000 Hz
>While my CPU is indeed at about 1.86Ghz, I rather doubt the ac97 link
>is at only 10kHz.
right. others have seen that too. It is a very busy loop when doing
that calibration and powermanagement is present.
Powermanagement is a killer for TSC. so the best bet is not to
select the TSC counter automatically. There is now  an ifdef  in
arch/x86/x86/tsc.c 1.5 to avoid selecting  TSC by default  when speedstep
is compiled in.

That should avoid the hickup.