NanoBSD on Raspberry Pi3

Hi all!

I am trying to build a NanoBSD image for a spare RPi3.

I started from an existing configuration I am using for a PCEngine APU2 
board, I use as an internal DNS and DHCP server. I'd like to replace it.

I'd also like to be able to upgrade using the altroot partition and then 
switching the default one, but am not sure how to do that, maybe I can 
play with efi variables, anyway I'm going to investigate this once I get 
at least FreeBSD booting.

Unluckily I am unable to make my image properly boot.

I have reworked my scripts to replicate how the official release images 
are made in structure. (copying a lot from src/release)

I got t the point where loader_lua.efi (renamed as the standard 
`/EFI/BOOT/bootaa64.efi` in the fat partition) loads, looks like it is 
scanning disks but then says:

ERROR: cannot open /boot/lua/loader.lua: no such file or directory.


It gives me a prompt, but even if I do have a working USB keyboard 
plugged in I am unable to interact (maybe this is normal at this stage?)

I guess it is failing to find the root filesystem but I don't know why. 
There is a valid root partition. Do I need to put some boot code in it 
to make loader recognize it?

Where could I find some more detailed information about u-boot and UEFI 
boot? Maybe I can help by creating some configuration file in the UEFI 
partition?

Thanks in advance for any indication.


Output of `gpart show` (fromthe image mounted as md):

=>     63  8617921  md1  MBR  (4.1G)
        63      961       - free -  (481K)
      1024    65536    1  fat32lba  [active]  (32M)
     66560   131072    2  freebsd  (64M)
    197632  4194304    3  freebsd  (2.0G)
   4391936  4194304    4  freebsd  (2.0G)
   8586240    31744       - free -  (16M)

=>      0  4194304  md1s3  BSD  (2.0G)
         0      128         - free -  (64K)
       128  4194176      1  freebsd-ufs  (2.0G)


(it looks quite similar to the official image one, as far as I can see)


Not sure what other information I can share, but I will send anything 
that can help shed some light.


-- 
Guido Falsi <mad@madpilot.net>