If you are on Solaris 2.x, You should use pkgadd to add the vendor supplied package. If you write your own drivers, you have to add it into
/kernel/drv directory, and provide .conf file if necessary. Also in the init.d
directory, you need to add necessary scripts to facilitate driver's probing and initialization(for instance, use "add_drv" to create device file,etc)
If you are on Linux platform, use modins to install driver modules(driver module is a kind of driver that can be dynamically load in kernel and linked with kernel symbol table).