Kernel PPS processing

Hal Murray hmurray at
Wed Jun 29 10:21:40 UTC 2016

If you turn on flag3 for a PPS driver on a Linux system, you get this error 
06-20T12:25:32 ntpd[988]: refclock_params: kernel PLL (hardpps, RFC 1589) not 

I poked around a bit.  Those options are in drivers/pps/Kconfig  Here is the 
key chunk:
config NTP_PPS
        bool "PPS kernel consumer support"
        depends on !NO_HZ
          This option adds support for direct in-kernel time
          synchronization using an external PPS signal.

          It doesn't work on tickless systems at the moment.

So I pulled over the sources and built a kernel with NO_HZ turned off and 
NTP_PPS turned on.

The next project is to figure out why it works so much better, or rather why 
the normal ntpd can't do a lot better.

These are my opinions.  I hate spam.

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