Kernel PPS processing

Achim Gratz Stromeko at
Tue Jul 5 05:35:40 UTC 2016

Gary E. Miller writes:
> Nothing at all about GPIO or timestamping.
> Did I miss something?

Maybe the fact that all the GPIO registers and the timestamp counter are
on the VC4 side of the SoC.  The Linux kernel just reads those when it
gets interrupted by the VC4, the ARM subsystem doesn't have any
connections of its own to the outside.

On another tangent back to NTP, I'm wondering if it wouldn't make sense
to offload the timestamp filtering at least to the VC4.  Most NTP boxes
would run headless anyway, so there'd be 16 processors sitting idle for
that sort of thing.

>> There seems to be nothing up yet for the BCM2837 (Pi3), but it's
>> basically just replacing the A7 cluster in the BCM2836 with an A8
>> cluster.
> Yeah, I'm wondering why the dealy in Linux kernel for 64 bit A8?

It wouldn't buy anyone anything of immediate use except having a
complete additional distro to build and maintain and more memory
pressure to deal with.  I suspect that eventually a 64bit port will be
added anyway to tick a checkbox somewhere.

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

SD adaptation for Waldorf rackAttack V1.04R1:

More information about the devel mailing list