Found #nvidia GPU driver set for #FreeBSD 580.105.08 is released upstream.
https://www.nvidia.com/en-us/drivers/details/257494/

Working fine for me on my Quadro P1000 (notebook), stable/15 at commit fe38c6769b19.

So filed PR Bug 290813
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=290813
and corresponding review D53596
https://reviews.freebsd.org/D53596
for upgrading #ports.