.\"	$OpenBSD: xp.4,v 1.2 2017/02/11 23:08:43 jmc Exp $
.\"
.\" Copyright (c) 2017 Kenji Aoyama.
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.Dd $Mdocdate: February 11 2017 $
.Dt XP 4 luna88k
.Os
.Sh NAME
.Nm xp
.Nd HD647180X I/O processor
.Sh SYNOPSIS
.Cd "xp0 at mainbus0"
.Sh DESCRIPTION
The file
.Pa /dev/xp
is an
.Xr mmap 2
capable interface to the memory area of the HD647180X I/O processor
(so-called "XP") on LUNA-88K and LUNA-88K2.
Byte offsets in this file are interpreted as relative memory addresses
of the I/O processor.
The range should be between 0x0 and 0xffff.
.Pp
The following
.Xr ioctl 2
call applies to
.Pa /dev/xp :
.Bl -tag -width 4n
.It Dv XPIOCDOWNLD Fa "struct xp_download"
Load binary and reset I/O processor.
.Bd -literal -offset indent
struct xp_download {
        u_int   size;
	u_char  *data;
};
.Ed
.Pp
The
.Va size
member specifies the loading binary size, in bytes.
The
.Va data
member points to the binary image.
.El
.Sh FILES
.Bl -tag -width /dev/xp -compact
.It Pa /dev/xp
.El
.Sh ERRORS
.Bl -tag -width Er
.It Bq Er EINVAL
The specified size is 0 or more than the I/O processor's memory size.
.It Bq Er ENOMEM
Memory could not be allocated for loading.
.El
.Sh SEE ALSO
.Xr ioctl 2
.Sh HISTORY
The
.Pa /dev/xp
file first appeared in
.Ox 6.1 .