Exclusive Use of DDI Access Handles

All PIO access by a driver must use Solaris DDI access functions from the ddi_getX, ddi_putX, ddi_rep_getX, and ddi_rep_putX families of routines. The driver should not directly access the mapped registers by the address returned from ddi_regs_map_setup(9F). (Avoid the ddi_peek(9F) and ddi_poke(9F) routines because they do not use access handles.)

The DDI access mechanism is important because it provides an opportunity to control how data is read into the kernel.