(And, yes, there is a question mark in the CPU device name - it
surprised me too, but it works with dev and it works with
find-device.)
You have a G3 upgrade, do you?
Older Apple OF versions know only about 601, 603 and 604 CPUs,
everything else becomes 60?
I think so, but I'm not really competent to be sure. There are
indications that I thought I do; my kernel config name includes "G3",
for example. The kernel says
cpu0 at mainbus0: 750 (Revision 2.2), ID 0 (primary)
cpu0: HID0 8090c0a4<EMCP,DOZE,DPM,ICE,DCE,SGE,BTIC,BHT>, powersave: 1
cpu0: 305.88 MHz, no-parity 512KB WB L2 cache (PB SRAM) at 2:1 ratio
That's another thing that had occurred to me, but without looking I
couldn't tell how feasible it was to make that value run-time
variable.
(I've often enough seen things that are set up once at startup and
then
end up with tantacles everywhere, so changing them live is messy. If
timebase-frequency is not one of them, great; a sysctl would be a
splendid alternative. I'll have to have a look.)