This concerns the FreeBSD-12.0-CURRENT-arm64-aarch64-RPI3-20170919-r323729.img.xz I have tried to get it to work multiple times with two virgin 32GB SanDisk Ultra memory cards. I have verified that one of the memory cards works with the 22-08-2017 snapshot after failing the newest. I have checked that I can view the MSDOS partition on windows. And the config.txt file is readable. The text the boot writes to the screen last for so short time it is not really readable. Image writing program : Etcher v 1.1.2 (the latest)
The latest version of FreeBSD-12.0-CURRENT for the Raspberry PI seems to work fine. FreeBSD-12.0-CURRENT-arm64-aarch64-RPI3-20170925-r323985.img.xz
The image dated 2017-09-26 is very slow due to activation of the Witness lock validation facility. From my point of view it would be very nice if each rease with Witness enabled also had a companion without.
Release images do indeed have witness disabled. But during the development of the -CURRENT branch -- currently 12 -- it is intentionally left on for debugging purposes. The idea is that anyone using that branch will accept all the disadvantages of being at the 'bleeding edge of development (or, build their own kernel/world, to taste.) Since the initial regression has been fixed I'm going to mark this one as Resolved.