xref: /freebsd-src/share/man/man4/man4.powerpc/ofw_console.4 (revision b2c76c41be32f904179efed29c0ca04d53f3996c)
1*0cdfc338SMarius Strobl.\"-
2*0cdfc338SMarius Strobl.\" Copyright (c) 2001 Miodrag Vallat.
3*0cdfc338SMarius Strobl.\" Copyright (c) 2005 Marius Strobl <marius@FreeBSD.org>
4*0cdfc338SMarius Strobl.\" All rights reserved.
5*0cdfc338SMarius Strobl.\"
6*0cdfc338SMarius Strobl.\" Redistribution and use in source and binary forms, with or without
7*0cdfc338SMarius Strobl.\" modification, are permitted provided that the following conditions
8*0cdfc338SMarius Strobl.\" are met:
9*0cdfc338SMarius Strobl.\" 1. Redistribution of source code must retain the above copyright
10*0cdfc338SMarius Strobl.\"    notice, this list of conditions and the following disclaimer.
11*0cdfc338SMarius Strobl.\" 2. Redistributions in binary form must reproduce the above copyright
12*0cdfc338SMarius Strobl.\"    notice, this list of conditions and the following disclaimer in the
13*0cdfc338SMarius Strobl.\"    documentation and/or other materials provided with the distribution.
14*0cdfc338SMarius Strobl.\"
15*0cdfc338SMarius Strobl.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16*0cdfc338SMarius Strobl.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17*0cdfc338SMarius Strobl.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18*0cdfc338SMarius Strobl.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19*0cdfc338SMarius Strobl.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20*0cdfc338SMarius Strobl.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21*0cdfc338SMarius Strobl.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22*0cdfc338SMarius Strobl.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23*0cdfc338SMarius Strobl.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24*0cdfc338SMarius Strobl.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25*0cdfc338SMarius Strobl.\"
26*0cdfc338SMarius Strobl.\"	from: OpenBSD: pcons.4,v 1.4 2003/06/02 16:16:26 miod Exp
27*0cdfc338SMarius Strobl.\"
28*0cdfc338SMarius Strobl.Dd January 16, 2021
29*0cdfc338SMarius Strobl.Dt OFW_CONSOLE 4 powerpc
30*0cdfc338SMarius Strobl.Os
31*0cdfc338SMarius Strobl.Sh NAME
32*0cdfc338SMarius Strobl.Nm ofw_console
33*0cdfc338SMarius Strobl.Nd "Open Firmware console"
34*0cdfc338SMarius Strobl.Sh SYNOPSIS
35*0cdfc338SMarius Strobl.Cd "cpu AIM"
36*0cdfc338SMarius Strobl.Cd "options OFWCONS_POLL_HZ=N"
37*0cdfc338SMarius Strobl.Pp
38*0cdfc338SMarius Strobl.Cd "options KDB"
39*0cdfc338SMarius Strobl.Cd "options DDB"
40*0cdfc338SMarius Strobl.Cd "options ALT_BREAK_TO_DEBUGGER"
41*0cdfc338SMarius Strobl.Sh DESCRIPTION
42*0cdfc338SMarius StroblThe
43*0cdfc338SMarius Strobl.Nm
44*0cdfc338SMarius Strobldriver provides a simple text console,
45*0cdfc338SMarius Stroblusing the Open Firmware services for input and output.
46*0cdfc338SMarius StroblIt will use the Open Firmware console devices set via the
47*0cdfc338SMarius Strobl.Va input-device
48*0cdfc338SMarius Strobland
49*0cdfc338SMarius Strobl.Va output-device
50*0cdfc338SMarius Stroblvariables.
51*0cdfc338SMarius Strobl.Pp
52*0cdfc338SMarius StroblThis driver is deprecated and only provided as a fallback console mechanism
53*0cdfc338SMarius Stroblif the real console hardware can not be driven by
54*0cdfc338SMarius Strobl.Fx .
55*0cdfc338SMarius Strobl.Pp
56*0cdfc338SMarius StroblIn case the
57*0cdfc338SMarius Strobl.Nm
58*0cdfc338SMarius Stroblconsole appears to work too slowly, its responsiveness probably can be improved
59*0cdfc338SMarius Stroblby including
60*0cdfc338SMarius Strobl.Cd "options OFWCONS_POLL_HZ=N" .
61*0cdfc338SMarius StroblWhen omitted,
62*0cdfc338SMarius Strobl.Dv OFWCONS_POLL_HZ
63*0cdfc338SMarius Strobldefaults to 4.
64*0cdfc338SMarius StroblFor example, on
65*0cdfc338SMarius Strobl.Tn Sun Ultra 2
66*0cdfc338SMarius Strobla value of 20 or higher works best.
67*0cdfc338SMarius StroblToo high values, on the other hand, can cause
68*0cdfc338SMarius Strobl.Nm
69*0cdfc338SMarius Stroblto unnecessarily consume CPU.
70*0cdfc338SMarius Strobl.Sh FILES
71*0cdfc338SMarius Strobl.Bl -tag -width ".Pa /dev/keyboard" -compact
72*0cdfc338SMarius Strobl.It Pa /dev/console
73*0cdfc338SMarius Strobl.It Pa /dev/keyboard
74*0cdfc338SMarius Stroblterminal input device in case the console input device is the keyboard
75*0cdfc338SMarius Strobl.It Pa /dev/screen
76*0cdfc338SMarius Stroblterminal output device in case the console output device is the screen
77*0cdfc338SMarius Strobl.It Pa /dev/tty[a-z]
78*0cdfc338SMarius Stroblterminal device in case both the console input and output device is tty[a-z]
79*0cdfc338SMarius Strobl.El
80*0cdfc338SMarius Strobl.Sh SEE ALSO
81*0cdfc338SMarius Strobl.Xr akbd 4 ,
82*0cdfc338SMarius Strobl.Xr powermac_nvram 4 ,
83*0cdfc338SMarius Strobl.Xr vt 4
84*0cdfc338SMarius Strobl.Sh HISTORY
85*0cdfc338SMarius StroblThe
86*0cdfc338SMarius Strobl.Nm
87*0cdfc338SMarius Strobldriver first appeared in
88*0cdfc338SMarius Strobl.Fx 5.0 .
89*0cdfc338SMarius Strobl.Sh AUTHORS
90*0cdfc338SMarius StroblThe
91*0cdfc338SMarius Strobl.Nm
92*0cdfc338SMarius Strobldriver was written by
93*0cdfc338SMarius Strobl.An Benno Rice Aq Mt benno@FreeBSD.org .
94*0cdfc338SMarius Strobl.Sh CAVEATS
95*0cdfc338SMarius StroblSince the Open Firmware will handle BREAK
96*0cdfc338SMarius Strobl(or Stop-A)
97*0cdfc338SMarius Stroblsequences before
98*0cdfc338SMarius Strobl.Nm ,
99*0cdfc338SMarius Stroblthe preferred way to enter
100*0cdfc338SMarius Strobl.Xr ddb 4
101*0cdfc338SMarius Stroblwhen using
102*0cdfc338SMarius Strobl.Nm
103*0cdfc338SMarius Stroblis to include
104*0cdfc338SMarius Strobl.Cd "options ALT_BREAK_TO_DEBUGGER"
105*0cdfc338SMarius Stroblin a ddb-enabled kernel, and enter the alternate BREAK sequence
106*0cdfc338SMarius Strobl(RETURN TILDE CTRL-b).
107*0cdfc338SMarius Strobl.Sh BUGS
108*0cdfc338SMarius StroblThe
109*0cdfc338SMarius Strobl.Nm
110*0cdfc338SMarius Strobldriver also not attach to the hardware resources it actually talks to.
111