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: > > * TIME_STATUS_NP > # 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 time. 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 _______________________________________________ Linuxptp-devel mailing list Linuxptp-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
