Richard, Thanks for the response. I should have said before, we are using 802.1AS and I have the 'gmCapable' set to 0, but it has no effect and the OC slave still assumes the GM role. Shouldn't that setting stop it from ever assuming the GM role? Maybe I'm missing something there about the BMC algorithm.
I did a test while capturing all packets at the A10 slave. It starts with the units being in sync, then I disconnect the GM and plug it back in about 15 seconds later. As far as the Announce messages, the GM is sending an announce message every second while it's connected, and then once it's reconnected they actually do sync up briefly. Then about 5 seconds after re-sync - the slave transmits an Announce message and then starts sending Sync/Follow up messages, and I don't see another Announce from the GM up until I stopped the capture. I did indeed notice if I bring the mac down and back up - it resyncs fine. John -----Original Message----- From: Richard Cochran <richardcoch...@gmail.com> Sent: Thursday, February 14, 2019 9:23 PM To: John Lemonovich <john.lemonov...@foresys.com> Cc: linuxptp-users@lists.sourceforge.net Subject: Re: [Linuxptp-users] A10 SoC ptp4l - can't resync after losing GM On Thu, Feb 14, 2019 at 09:54:42AM -0600, John Lemonovich wrote: > I have been running ptp4l on various intel FPGA Arria 10 SoC > implementations, including one with the 10Gb MAC and a few with the > HPS EMAC (stmmicro 1GbE) and it's all working very well. One issue > we're seeing is, if our A10 slave has been sync'd with a GM clock, and > then that GM goes away (power cycled or even cable > disconnected/reconnected) - our > A10 ptp4l app won't resync to that same GM. When the cable is > reconnected, ptp4l does indeed select that same GM briefly as the BMC, > but then it loses it upon announce receipt timeout expires and it > never comes back. I tried higher thresholds for > annoucereceipttimeout, but it didn't help. Use tcpdump to see whether Announce messages are missing. Thanks, Richard _______________________________________________ Linuxptp-users mailing list Linuxptp-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-users
