FreeBSD images for these boards are 64-bit.

• Vendor website: https://www.pine64.org/

• Due to its special u-boot code, it is not possible to use the GENERIC image; instead, there are particular PINE64 images. Examples:
  • http://ftp.freebsd.org/pub/FreeBSD/snapshots/ISO-IMAGES/12.0/FreeBSD-12.0-STABLE-arm64-aarch64-PINE64-20190718-r350087.img.xz
  • http://ftp.freebsd.org/pub/FreeBSD/snapshots/ISO-IMAGES/13.0/FreeBSD-13.0-CURRENT-arm64-aarch64-PINE64-LTS-20190718-r350103.img.xz

• MarkLinimon has a pine64. The -CURRENT 20190718 image is known to work.