I did the fllowing two steps
1）The ubuntu system host only supports software clock synchronization (ethtool - T eno1), as the main end, enter the command:
‘sudo ptp4l -i eno1 -m -S’
2）Jetson AGX Xavier (L4T 35.1) as the slave, enter the command:
‘sudo ptp4l -i eno1 -m -S -s’
The result is that L4T 32.4.3 successfully synchronizes the software clock, while L4T 35.1 fails to synchronize
The main printing during failure is
‘timed out while polling for tx timestamp’ and
‘increasing tx_timestamp_timeout may correct this issue, but it is likely caused by a driver bug’ and
‘send sync failed’.