Ethernet Status
My ClearFog Base can boot into FreeBSD 12.0-ALPHA7 7fe1a714461(master) ARMADA38X, but the second ethernet port next to the SFP socket doesn't seem to be configured properly. The first ethernet port, the one near the USB connectors, works well. The base device tree dtb is compiled using sys/gnu/dts/arm/armada-388-clearfog-base.dts from the FreeBSD source.
The two ethernet ports are connected to an unmanaged switch. When in u-boot, both link lights on the switch are on; both lights on the ClearFog are on with a high duty cycle, but constantly flickering. After control is passed to the FreeBSD kernel, the link light on the switch corresponding to the second ethernet port goes out and the link light on the ClearFog stays on without flickering.
The console (and dmesg) indicate that the second ethernet port has no carrier. I don't think that is a hardware problem, because, without touching the connections or the switch, an SD card with a Debian image can be inserted and both ethernet ports are fully functional.
What configuration might be required so that the interface detects a carrier?
pygr

Ethernet Status Not Operational

It will list both the network adapters being used, as well as those that have been used in the past, on the computer. It will give you three statuses of the devices: Active devices will be shown with a green status icon. Non-operational devices will be shown with a yellow status icon. Disconnected devices will be shown with a red status icon. Shows Network Speed and Data Usage for each adapter See the status of your LAN/Ethernet and with other network interface connection right from the menu bar. This utility adds a neat icon on the menu bar which lets you know the status of the connection and other stats like your IP address, mac address, upload and download speed, data usage etc.