The ethernet interface over PCIe(endpoint mode) not work

Hi hermes_wu,

Please try below command to disable network manager:

$ sudo systemctl stop NetworkManager.service
$ sudo systemctl disable NetworkManager.service

Add the patch on EP and set static IP from both side.
You can reference detail steps from: Jetpack5.0.2 Xavier pcie endpoint mode [repetition] - #9 by WayneWWW