> It looks like the IRQ is asserted on RESET completion and expects a data > chunk from host to deassert the IRQ. I used to test the driver in RPI 4 > using iperf3. For some reason I never faced this issue, may be when the > network device is being registered there might be some packet > transmission which leads to deliver a data chunk so that the IRQ is > deasserted. If you have IPv6 enabled, the network stack will try to add a link local IPv6 address to the interface, which means performing a Duplicate Address Detection. That means sending a few packets. Try disabling IPv6 if you want to reproduce the problem. Andrew