Rewritten Xtensa CCOUNT driver along the lines of all the other new
drivers. The new API permits much smaller code.
Notably: The Xtensa counter is a 32 bit up-counter with a comparator
register. It's in some sense the archetype of this kind of timer as
it's the simplest of the bunch (everything else has quirks: NRF is
very slow and 24 bit, HPET has a runtime frequency detection, RISC-V
is 64 bit...). I should have written this one first.
Note also that this includes a blacklist of the xtensa architecture on
the tests/driver/ipm test. I'm getting spurious failures there where
a k_sem_take() call with a non-zero timeout is being made out of the
console output code in interrupt context. This seems to have nothing
to do with the timer; I suspect it's because the old timer drivers
would (incorrectly!) call z_clock_announce() in non-interrupt context
in some contexts (e.g. "expiring really soon"). Apparently this test
(or something in the IPM or Xtensa console code) was somehow relying
on that on Xtensa. But IPM is a Quark thing and there's no particular
reason to run this test there.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
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