can't actually get the board to boot FreeBSD from a microSD card. It behaves as if there is no SD card present.
Have you tried holding down the "boot" button to start from sdcard?
You might have to whip up your own image.
I think the default
beaglebone-black.dts might be a problem as the blue looks like alot of hardware changes.
FreeBSD Arm is now using all the Linux GNU DTS stuff in the
/src/sys/gnu/dts dir.
So maybe do some Linux dumps with
ofwdump -a
and then work that back to FreeBSD.
You might just need to use a
beaglebone-blue.dtb instead of
beaglebone-black.dtb.
The
/boot/dtb directory has these critical files:
beaglebone.dtb
beaglebone-black.dtb
ufw.dtb
The other am335x files are actually symlinks to the above.
So the first file should be applicable to all Beaglebones
Whereas the
beaglebone-black.dtb is specific to the Black.
So you either need to mod that file and delete all the non-relevant onboard computer periphery or find the file that the Linux distro is using.
Like I say it might be as simple as adding a
beaglebone-blue.dtb to your
/boot/dtb dir.
(Note this does not mean you can simply copy the Linux file. It must be decompiled on Linux and transfered over then recompiled in FreeBSD)
I would really look at your shipping Linux distro. Maybe image the "mmc" distro and work on it offline.
Now those files from the FreeBSD
/boot/dtb directory are the finish DTB blobs.
You could also modify KERNCONF=BEAGLEBONE into BEAGLEBONEBLUE and add the needed Blue DTS files there.
I have recent amd64 cross-compile instructions up here for BBB. This would be the proper route.
FreeBSD on Beaglebone will actually relinquish control of the onboard LED's so when booted no board LED's are on except for the ethernet jack activity lights. The LED's are available for gpio usage instead.