One of our new designs include the LAN port KSZ8895RQ and I have found a problem with it. After several proofs, I have realized that the problem is that it is only working when I have something connected to the port 1. If I connect my PC to the port 1, everything works fine, if I don't connect anything, nothing is working.
The ports are connected the following way:
- Port 1: to an Ethernet connector, used to connect a PC
- Port 2: to another Ethernet connector, used to connect a PC
- Port 3: empty, future uses
- Port 4: to another board
- Port 5: to the main CPU through the RMII interface
The ports 4 and 5 are always connected but I cannot ping the board connected to the Port 4 from the main CPU if the Port 1 is not connected. Can any of you helping me with this? It seems that the phy driver is only working if it is able to connect through the Port 1 of the switch. I use the SPI port to configure the switch