Re: [Linuxptp-users] Hardware PTP clock synchronization

[Richard C. <ric...@gm...>]

On Mon, Aug 05, 2013 at 02:58:12PM +0300, Гаврилов Александр wrote:
> Hello!.
> 
> Intel® 82576 Gigabit Ethernet Controller Datasheet:
> "On both transmit and receive sides the timestamp values are locked in registers until values are read by
> software. As a result if a new PTP packet that requires time stamp arrives before software access it is 
> not time stamped. In some cases in the receive path a packet that was timestamped might be lost and 
> not reach the host. To avoid a deadlock condition on the time stamp registers the software should keep 
> a watch dog timer to clear locking of the time stamp register. The interval counted by such a timer 
> should be at least higher then the expected interval between two Sync or Delay_Req packets depends 
> on the node state (Master or Slave)."
> 
> How  should  I  modify the source code of igb driver (or ptp4l) to use
> the timer?

The timer is already implemented in the driver.

Moreover, the text you quote is about the *receive* path. You issue is
occurring on the *transmit* path.

Thanks,
Richard