For the Jetson orin board,How to up PCIe EP mode link in the tvnet driver?

Hi,

I want to connect two Orin devkit be based on Ethernet Interface through PCIE C5.

I according to PCIe Endpoint Mode — Jetson Linux
Developer Guide 34.1 documentation

and Bringing up an Ethernet Interface over PCIe,

On the root port system:

pegasus@pegasus-desktop:~$ lspci

0001:00:00.0 PCI bridge: NVIDIA Corporation Device 229e (rev a1)

0001:01:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8822CE 802.11ac PCIe Wireless Network Adapter

0004:00:00.0 PCI bridge: NVIDIA Corporation Device 229c (rev a1)

0004:01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd Device a809

0005:00:00.0 PCI bridge: NVIDIA Corporation Device 229a (rev a1)

0005:01:00.0 Network controller: NVIDIA Corporation Device 2296

and Successfully mounted the eth1 device.

On the endpoint device:

bind tvnet drive to pcie C5 ep(ln -s functions/pci_epf_tvnet/func1 controllers/141a0000.pcie_ep/),dmesg

[ 121.934647] pci_epf_tvnet pci_epf_tvnet.0: tvnet_ep_open: PCIe link is not up

[ 121.952300] pci_epf_tvnet pci_epf_tvnet.0: tvnet_ep_open: PCIe link is not up

[ 121.963978] pci_epf_tvnet pci_epf_tvnet.0: tvnet_ep_open: PCIe link is not up

[ 121.976607] pci_epf_tvnet pci_epf_tvnet.0: tvnet_ep_open: PCIe link is not up

[ 121.991189] pci_epf_tvnet pci_epf_tvnet.0: tvnet_ep_open: PCIe link is not up

but Successfully mounted the eth1 device.

up two Orin eth1 dev and assign static IP addresses:

pegasus@pegasus-desktop:/sys/kernel/config/pci_ep$ ping 192.168.2.2

PING 192.168.2.2 (192.168.2.2) 56(84) bytes of data.

From 192.168.2.3 icmp_seq=1 Destination Host Unreachable

I want to ask,

1. What causes the network failure?

2，How to up PCIe EP mode link in the tvnet driver?