FreeBSD on the Raptor Talos II
The Talos II mainboard from Raptor Computing Systems has been known to be usable with FreeBSD since late in 2018.
<More documentation to be added>
ELFv2 Petitboot kexec bug
If you are testing an ELFv2 kernel (i.e. one built using a modern compiler rather than the in-tree gcc 4.2.1), be aware that the kexec used by Petitboot in all versions of the Talos II PNOR prior to the upcoming 2.0 release contain a kexec bug that prevents booting.