i have both 6ul/6ull board and they all have two etherent port using lan8720a phy.
linux kernel i have tried 4.15/4.4.
After warm reboot, the second ethernet port works well.
But after cold reboot，the second ethernet port do not work
i have known that it's a power-on sequence problem.But i'm a beginner of linux,i do not know what to do next.
Can someone tell me how to check about it?