Why fpgainfo tool fails after testing with Data Plane Development Kit (DPDK) on Intel® FPGA Programmable Acceleration Card N3000?

After testing with Data Plane Development Kit (DPDK), fpgainfo utility may fail with the following error:

api-shell.c:518:opae_enumerate() **ERROR** : fpgaEnumerate() failed for "libxfpga.so"Error enumerating resources: exception

This error occurs because the FPGA is not bound to the Open Programmable Acceleration Engine (OPAE) FPGA driver. 

To work around this problem, unbind from the vfio-pcie driver and rebind to the OPAE driver by performing the following steps:

1. Unbind from vfio driver:

    $ sudo rmmod vfio-pci

2. Rebind to OPAE driver:

 $ modprobe intel-fpga-pci

 $ echo 0000:BB:DD.F > /sys/bus/pci/drivers/intel-fpga-pci/bind

 $ sudo modprobe i40e

3. Bind the XL710 interfaces to i40e driver:

$ sudo ./usertools/dpdk-devbind.py -b i40e 14:00.0 14:00.1 16:00.0 16:00.1

Note: In the command, replace the appropriate B:D:F value that corresponds to the FPGA and XL710.