L4tbr0 USB Serial/Ethernet bridge does not work on custom carrier board, JetPack 5.1.1

I’m trying to rebuild a custom kernel image for our carrier with Jetson Orin NX.
I got a problem with L4tbr0 USB Serial/Ethernet bridge.
On Jetson Orin NX development kit, the host PC can detect and connect to Jetson via L4tbr0 USB Serial/Ethernet bridge. But on our carrier board, this function look likes not working.
This is a message from dmes: “l4tbr0: port 1(rndis0) entered blocking state”.

Is there any modify I need to add before building custom kernel image to make L4tbr0 USB Serial/Ethernet bridge work on our carrier board ?

Sorry for the late response, is this still an issue to support? Thanks

Hi kayccc,
Yes, this issue still not solve yet.
I have check our carrier board with Jetson Xavier NX, no problem occurred.
Do you have any idea ?


Is you carrier board designed for Xavier NX in the beginning?
Have you checked Jetson Orin Nano Series, Jetson Orin NX Series, and Jetson Xavier NX Series Interface Comparison & Migration Application Note ?

Hi kayccc,

No, we are targeting the Jetson Orin NX for the beginning.
We have experience with Jetson Xavier NX. We know that Jetson Xavier NX and Jetson Orin NX as same size but not fully compatible.
We notice that we must modify dts file for ignore eeprom for our carrier board. Do we need to modify something or any trick to do with L4tbr0 USB Serial/Ethernet bridge ?

Is it the same USB port on your board and devkit? What’s the difference between yours and devkit? It looks like board issue since it work well on devkit.

Orin NX devkit by default uses fusb301 for type C. Thus, default dtb behavior will be for this fusb301 type C configuration.

If your custom board totally has no such design, then it will lead to problem. How did you flash your module?

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