Kernel PPS processing

Achim Gratz Stromeko at
Sun Jul 3 10:10:44 UTC 2016

Eric S. Raymond writes:
> Gary E. Miller <gem at>:
>> Anyone got a guess what the equivalent RasPi setting to turn off
>> power saving would be?
> turbo=1 in /boot/config.txt, I think. See also

No.  That used to be "force_turbo=1", but is not needed anymore.  You
simply define the maximum (and perhaps minimum) frequencies in
/boot/config.txt and chose the proper CPUfreq governor.  Default is
ondemand, you will either want powersave (to keep at the low frequency)
or performance (force maximum frequency).  So far I haven't seen a
difference between those when it comes to NTP performance, but I'm
running two isolated DCF77 clocks only at the moment.

Besides switching between two frequencies there aren't any powersave
features like the modern x86 has.  I can't find any obvious benefit from
using nohz=off on the kernel line either, but then I'm not yet using a
GPS receiver for the PPS.  Keep in mind that the PPS timestamping is
actually done by the VC4 and not the ARM in the BCM SoC.

+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

SD adaptations for KORG EX-800 and Poly-800MkII V0.9:

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