NAME
ibus
- pmax internal I/O space driver
SYNOPSIS
ibus0 at mainbus0
ibus0 at tc? slot ? offset ?
DESCRIPTION
ibus
is a virtual device corresponding to the pmax internal I/O space found
on DEC 2100, 3100, 5100 and 5000/200 systems.
Internal I/O space spans the pmax physical address space, and is
mapped permanently in the kernel virtual space at the very early time
of the kernel startup procedure.
ibus
driver manages the internal I/O space of pmax.
-
Address range management to avoid confliction of address space of
which devices probe by touching hardware port is difficult.
-
Interrupt vector management.
-
bus_space(9)
and
bus_dma(9)
implementation.
-
Other utility functions.
ibus
is always required to run the
NetBSD
kernel.
SEE ALSO
intro(4),
bus_dma(9),
bus_space(9)