[Bug 202651] cpufreq no longer works in 10.2 on Intel D525MWV

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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=202651

--- Comment #1 from Viktor Štujber <viktor.stujber at gmail.com> ---
After failing to find the regression window and discovering that the previous
kernel with the new userland also exhibits the problem, I again tried searching
for existing discussions about the subject.

I found
https://lists.freebsd.org/pipermail/freebsd-stable/2015-March/082034.html from
march 2015 which points to a 1 year old change in HEAD,
https://svnweb.freebsd.org/base?view=revision&revision=265329 . Here the
committer references some other mailing list discussion, which concluded that
P-state power management is not effective and can interfere with C-state power
management.

That is nice and all, but this Intel Atom CPU does not have any C-state power
management. Using P-states has a measurable impact (a few watts). Undoing the
changes to /boot/device.hints is what I did for now.

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