[ ... reworked CPU speed calibration ... ]
> Also (assuming this all works), I'm not sure whether to put this into
> sys/arch/mips or not.  The newsmips currently uses the same DELAY()
> macro as the pmaxes; but do we want to embed this for all mips machines?

It seems OK to me if having such the calibration assistant routines
will not hurt possible other MIPS ports.  There are computers which
have high resolution timer/counter(s) available for DELAY() by
on-the-fly reprogramming, and such a counter could be used for CPU
speed calibration itself. 

That is, there should be no hard reason CPU calibration is
specifically tied with MC146818 decenders.  It's a bad practice to
attribute CPU calibration with 'mcclock' keyword as it would hurt
other MIPS ports.

Tohru Nishimura
Information Technology Centre
Nara Institute of Science and Technology