Should the HAVE_KERNEL_PLL conditional be abolished?

Hal Murray hmurray at
Mon Dec 4 19:35:35 UTC 2017

>> >> First: capture pulse timing info.
>> >> Second: adjust "drift" on system clock
>> >> Third: in kernel PLL to adjust drift from PPS pulses
> You need drift correction implemented in the kernel to get decent 
>> timekeeping.  ntp_adjtime is just the API.
> For the drift correction, yes.  Am I correct that it doesn't do the other
> two things?

Yes.  The PPS stuff uses time_pps_*
No man pages.  I assume everybody follows the RFC.

Turning on/off the kernel PLL uses time_pps_kcbind
On linux, it's an ioctl via PPS_KC_BIND
details in /usr/include/linux/pps.h and /usr/include/sys/timepps.h and 

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