/etc/driver/drv
The directory /etc/driver/drv is a location where administrative driver.conf customizations can be placed.
Separating vendor driver.conf files and administratively-customized driver.conf files allows the system to be upgraded with new vendor driver.conf files without overwriting the administrative customizations.
prtconf(1M), driver.conf(4), ddi_prop_exists(9F), ddi_prop_lookup(9F)