Ethernet and Rev. 1.9

short story: ethernet port doesn’t seem to work. How do I fix it?

long story:
I’ve been working on a Hummingboard2 Gate (v1.4) with SOM v1.5 (I think) and everything was working great. A colleague wanted to check whether the 1.9 version would also work, so we replaced the old som with a new one and tried to install Debian 12.11 on its emmc from SD-card. During the installation process, the debian installer complains about not being able to find the DHCP. It gives as a possible reason that the network is not working.
If we continue the installation process, a minimal version of debian is installed and boots up, but ethernet does not seem to be working. At start up linux says: ‘phy link never came up’.

If I reboot the system and stop at U-boot, I can assign a ip-address to the system. If i do, I can ping from U-boot to our gateway. This suggests that the ethernet port does work. I am unable to ping the hummingboard from my computer except if I do the following:

  • I have the ping running on my computer to the Hummingboard.
  • I start a ping from U-boot to an address that will not be reached.
    While U-boot is trying to ping, the ping from my computer suddenly starts responding. As soon as U-boot is done trying to ping, the computer ping also stops.
    To me this shows that the ethernet port does work with the new SOM.

Can anyone give me some leads as to how to solve this?