Re: Linux 2.6.29-rc6

From: Ingo Molnar
Date: Thu Mar 05 2009 - 03:44:19 EST



* john stultz <johnstul@xxxxxxxxxx> wrote:

> > Ingo, Thomas: On the hardware I'm testing the fast-pit
> > calibration only triggers probably 80-90% of the time. About
> > 10-20% of the time, the initial check to
> > pit_expect_msb(0xff) fails (count=0), so we may need to look
> > more at this approach.

We definitely need to improve calibration quality.

The question is - why does fast-calibration fail 10-20% of the
time on your test-system? Also, why exactly do we miscalibrate?
Could you please have a look at that?

One theory would be that the PIT readout is unreliable. Windows
does not make use of it, so it's not the most tested aspect of
the PIT. Is that what happens on your box?

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/