Side note: I'd like to change that.
250ms is a _loong_ time. It's a really really long time. It's
human-noticeable. A quarter of a second at boot is just too long.
We have a couple of options:
- make the PIT calibration shorter
I suspect we could easily make the PIT calibration be just 5ms rather
than 50ms. Yes, yes, it will be less precise, but the PIT counts at
1.1MHz or something, so we're still talking about 5000+ ticks of the
clock.
So we'll get within a fraction of a percent. We could then decide that
_if_ the HPET/PMTIMER matches the PIT, we'll decide to use that as the
reference time, because it would possibly have higher accuracy.
- do other things while calibrating.
Especially for HPET/PM_TIMER, we could actually do some other stuff
while it is calibrating, since those calibrations only depend on the
end/beginning being "close enough". This seems like it would be pretty
hard to actually do sanely, though (there's still the issue of the
HPET/PM_TIMER overflowing, although with 24 bits that should be on the
order of several seconds, I dunno)
Anyway, 250ms really is too long.
Linus
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