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.Dd February 17, 2017
.Dt EBUS 4 emips
.Os
.Sh NAME
.Nm ebus
.Nd eMIPS Extensible I/O BUS driver
.Sh SYNOPSIS
.Cd "ebus0 at mainbus0"
.Sh DESCRIPTION
.Nm
is a virtual device for the Extensible I/O BUS realized with eMIPS
on FPGA boards such as the BEE3, Xilinx XUP, and Xilinx ML40x systems.
.Pp
Devices on the BUS can generally be relocated and can be found by
scanning the Peripheral Mapping Table at the top of the BUS physical space.
The driver is responsible for identifying devices that are currently available,
and to map them into the kernel virtual space during the kernel startup procedure.
.Pp
The
.Nm
driver manages the Extensible I/O BUS on eMIPS and provides
.Pp
.Bl -bullet -offset indent
.It
Address range management to avoid conflicts.
.It
Interrupt vector management.
.It
Other utility functions.
.El
.Pp
.Nm
is always required to run the
.Nx
kernel.
.Sh SEE ALSO
.Xr emips/ace 4 ,
.Xr emips/dz 4 ,
.Xr emips/eclock 4 ,
.Xr emips/enic 4 ,
.Xr emips/intro 4