Hi Richard,

> -----Original Message-----
> From: Richard Cochran <richardcoch...@gmail.com>
> Sent: Friday, October 11, 2019 12:11 PM
> To: Y.b. Lu <yangbo...@nxp.com>
> Cc: Rodney Cummings <rodney.cummi...@ni.com>;
> linuxptp-devel@lists.sourceforge.net; rodney.greenstr...@gmail.com;
> Андрей Иванов <ia...@yandex.com>; Erik Hons <erik.h...@ni.com>
> Subject: Re: Re: [Linuxptp-devel] [Linuxptp-users] How do I implement Sync
> message receive timeout according to Automotive and 802.1 AS profiles?
> On Fri, Oct 11, 2019 at 03:24:50AM +0000, Y.b. Lu wrote:
> > [Y.b. Lu] Sorry, I didn't mean to change it now.
> > Initially I thought that end instance was different with OC. Current end
> instance of linuxptp was totally an OC without utilizing follow_up_tlv and 
> free
> running clock.
> > I thought 802.1AS should use free running clock for efficiency, and maybe
> application APIs are needed to be implemented.
> >
> > But now I understand current end instance of linuxptp is conformant to
> 802.1AS.
> > Although it doesn't support free running clock, we don't have to support it
> now to make it totally same with standard.
> But it does support free running!
> There is even an option called "free_running" and this special management
> message:
> # designed for use with gPTP and free_running
>   master_offset              0
>   ingress_time               0
>   cumulativeScaledRateOffset +0.000000000
>   scaledLastGmPhaseChange    0
>   gmTimeBaseIndicator        0
>   lastGmPhaseChange          0x0000'0000000000000000.0000
>   gmPresent                  false
>   gmIdentity                 e89a8f.fffe.74f796

[Y.b. Lu] Thanks for pointing out this.
I'm just not familiar how applications use 802.1AS synchronized time.

For physical clock adjustment, I know we have /dev/ptpx device to access for 
For free running clock, I can see master_local_rr is used for master/local rate 
ratio which makes sense for TC to synchronize frequency,
but for OC/BC/end instance, where to find the synchronized time. Is the 
TIME_STATUS_NP info enough for applications?

Sorry, I lack the knowledge of applications using 802.1AS :(

> Thanks,
> Richard

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