eth0 is the top left connector (the upper connector marked “c” in the motherboard manual).
I burned RHELSA RHEL-7.2-20151030.0-Server-aarch64-boot.iso to a USB key and inserted it into the machine.
I had to chain-load Tianocore (UEFI firmware) as described here. This requires that you run a TFTP server. You should also set the u-boot ipaddr and serverip environment variables so that u-boot can contact your TFTP server.
Once in UEFI, do these commands at the UEFI shell:
set MAC0 xx:xx:xx:xx:xx:xx
Then reboot again, go into the UEFI shell again, and:
fs0: cd \EFI\BOOT BOOTAA64
I also had to stop the grub configuration and edit the linux kernel command line, adding console=ttyS0,115200 acpi=off vnc at the end.
acpi=off is needed because the SBBR requires ACPI support, which the version of TianoCore which APM/Gigabyte have provided does not supply (or it’s broken in some way).acpi=off is required to boot the installer, I found that RHELSA itself will actually work with ACPI. So you have to remove acpi=off from the kernel command line after installation.
After that you should see lots of kernel messages, and with luck you’ll arrive in Anaconda and it will print details of the VNC server. Finally, I have a RHELSA installer …
Richard WM Jones 
I have executed “set MACn … ” command and after CentOS boot up I see MAC address on all four ifcs. I have tried ifconfig up on both fiber ifcs and both become visible for ifconfig. Unfortunately, link is not up, LEDs of both ifcs are OFF. Does any one know hotwo make fibre ifcs working?