ConnectX-6/BlueField-2 ports can be individually configured to work as InfiniBand or Ethernet ports. By default both ConnectX-6/BlueField-2 ports are initialized as InfiniBand ports. If you wish to change the port type, use the mlxconfig script after the driver is loaded.
For further information on how to set the port type in ConnectX-6/BlueField-2, please refer to the MFT User Manual (www.mellanox.con → Products → Software → InfiniBand/VPI Software → MFT - Firmware Tools).