Re: [Linuxptp-users] Software Based Timestamps does not work

[Keller, J. E <jac...@in...>]

> -----Original Message-----
> From: Richard Cochran [mailto:ric...@gm...]
> Sent: Saturday, February 18, 2012 12:06 AM
> To: Keller, Jacob E
> Cc: lin...@li...
> Subject: Re: [Linuxptp-users] Software Based Timestamps does not work
> 
> On Fri, Feb 17, 2012 at 11:38:40PM +0000, Keller, Jacob E wrote:
> 
> > When enabling software based timestamps via the '-s' switch, the
> > program switches to the faulty state instantly after transmitting a
> > packet that should be timestamped because the software timestamp is
> > never obtained. With further investigation, it turns out that
> > software timestamping appears to be disabled. I tested with the
> > kernel timestamping.c program, and indeed just selecting
> > sof_timestamping_tx_software, sof_timestamping_rx_software and
> > sof_timestamping_software does not return timestamps. The additional
> > option of sof_timestampns must also be enabled.
> 
> But that gets the time stamp using the legacy BSD loopback method.
> I did not support this in ptp4l because it only works on UDPv4
> packets.
> 
Hmm.. When I added SO_TIMESTAMPNS, the value did appear in the software timestamping. I'll take a look at the driver and see if that line is there. Thanks for the input. (I was not aware of that)