On Wed, Oct 31, 2012 at 8:46 PM, Richard Cochran
[off-list ref] wrote:

On Wed, Oct 31, 2012 at 05:00:55PM +0800, Bob Liu wrote:

quoted

On Wed, Oct 31, 2012 at 4:36 PM, Richard Cochran
[off-list ref] wrote:

quoted

On Wed, Oct 31, 2012 at 02:29:23PM +0800, Bob Liu wrote:

quoted

Any guide how to use ptp4l to sync system time between two machines
over ethernet?

You can run ptp4l on two machines like this

  ptp4l -i eth0 -q -v     # master
  ptp4l -i eth0 -q -v -s  # slave

Thank you.
But i'm still failed to sync system time.

On mater:
-------------------------------
root:/> date
Wed Dec 20 01:31:02 UTC 2006
root:/>
root:/>   ptp4l -i eth0 -q -v
ptp4l[33.520]: selected /dev/ptp0 as PTP clock
ptp4l[33.520]: m
ptp4l[33.520]: driver rejected most general HWTSTAMP filter
ptp4l[33.520]: port 1: INITIALIZING to LISTENING on INITIALIZE
ptp4l[33.524]: port 0: INITIALIZING to LISTENING on INITIALIZE
ptp4l[39.524]: port 1: LISTENING to MASTER on ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES
.....

-----------------------------
On slave:
root:~> date
Fri Jan  2 13:16:07 UTC 1970

root:~>   ptp4l -i eth0 -q -v -s
ptp4l[39.624]: selected /dev/ptp0 as PTP clock
ptp4l[39.628]: m
ptp4l[39.628]: driver rejected most general HWTSTAMP filter
ptp4l[39.628]: port 1: INITIALIZING to LISTENING on INITIALIZE
ptp4l[39.632]: port 0: INITIALIZING to LISTENING on INITIALIZE
ptp4l[39.664]: port 1: new foreign master 00e022.fffe.fe8529-1
ptp4l[43.672]: selected best master clock 00e022.fffe.fe8529
ptp4l[43.676]: port 1: LISTENING to UNCALIBRATED on RS_SLAVE
ptp4l[44.688]: master offset -7968957480 s0 adj      +0 path delay       8120
ptp4l[45.692]: master offset -7968953124 s0 adj      +0 path delay       9076
ptp4l[46.696]: master offset -7968947340 s0 adj      +0 path delay       8860
ptp4l[47.700]: master offset -7968941884 s1 adj      +0 path delay       8860
ptp4l[48.704]: master offset       4564 s2 adj   +4564 path delay       8860
ptp4l[48.704]: port 1: UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED
ptp4l[49.708]: master offset       5154 s2 adj   +6523 path delay       9086
ptp4l[50.712]: master offset       3686 s2 adj   +6601 path delay       9322
ptp4l[51.716]: master offset       2582 s2 adj   +6603 path delay       9322
ptp4l[52.720]: master offset       1362 s2 adj   +6158 path delay       9438
ptp4l[53.724]: master offset        658 s2 adj   +5862 path delay       9438
ptp4l[54.728]: master offset        -85 s2 adj   +5317 path delay       9685
ptp4l[55.732]: master offset       -113 s2 adj   +5263 path delay       9873
ptp4l[56.748]: master offset         86 s2 adj   +5428 path delay       9930
ptp4l[57.740]: master offset        166 s2 adj   +5534 path delay       9930
ptp4l[58.744]: master offset       -247 s2 adj   +5171 path delay      10151
ptp4l[59.748]: master offset        -39 s2 adj   +5305 path delay      10151
ptp4l[60.752]: master offset        217 s2 adj   +5549 path delay      10151
ptp4l[61.756]: master offset        256 s2 adj   +5653 path delay      10128
.....

This looks perfect. Did you fixup the wrong time stamp shift?

quoted

root:~> date
Fri Jan  2 13:16:45 UTC 1970
root:~>

The system time in slave didn't change.

That is correct. Using RAW time stamping and PHC, the time in the PHC
changes, but not the system time. The system time may be slaved to
the PHC time using the phc2sys program.

How to use it？

ptp4l -i eth0 -q -v     # master
ptp4l -i eth0 -q -v -s  # slave
And on slave i should also start:  phc2sys -s /dev/ptp0 -i eth0?
But this can't work.

Anyhow, it looks like this is working fine to me.

Thanks,
Richard

-- 
Regards,
--Bob