Re: [PATCH v3 net-next 00/17] PTP support for the SJA1105 DSA driver

From: Vladimir Oltean
Date: Fri Jun 07 2019 - 05:47:31 EST


On Fri, 7 Jun 2019 at 06:32, Richard Cochran <richardcochran@xxxxxxxxx> wrote:
>
> On Thu, Jun 06, 2019 at 04:40:19PM +0300, Vladimir Oltean wrote:
> > Plain and simply because it doesn't work very well.
> > Even phc2sys from the system clock to the hardware (no timestamps
> > involved) has trouble staying put (under 1000 ns offset).
> > And using the hardware-corrected timestamps triggers a lot of clockchecks.
>
> It sounds like a bug in reading or adjusting the HW clock. Is the HW
> clock stable when you don't adjust its frequency?

How can I tell that for sure?

>
> Thanks,
> Richard