2 * Mach Operating System
3 * Copyright (c) 1992, 1991 Carnegie Mellon University
6 * Permission to use, copy, modify and distribute this software and its
7 * documentation is hereby granted, provided that both the copyright
8 * notice and this permission notice appear in all copies of the
9 * software, derivative works or modified versions, and any portions
10 * thereof, and that both notices appear in supporting documentation.
12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
16 * Carnegie Mellon requests users of this software to return to
18 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
19 * School of Computer Science
20 * Carnegie Mellon University
21 * Pittsburgh PA 15213-3890
23 * any improvements or extensions that they make and grant Carnegie Mellon
24 * the rights to redistribute these changes.
26 * from: Mach, Revision 2.2 92/04/04 11:34:26 rpd
27 * $FreeBSD: src/sys/boot/pc98/boot2/serial_8251.S,v 1.1.2.1 2000/04/16 03:55:16 nyan Exp $
28 * $DragonFly: src/sys/boot/pc98/boot2/Attic/serial_8251.S,v 1.2 2003/06/17 04:28:18 dillon Exp $
32 Copyright 1988, 1989, 1990, 1991, 1992
33 by Intel Corporation, Santa Clara, California.
37 Permission to use, copy, modify, and distribute this software and
38 its documentation for any purpose and without fee is hereby
39 granted, provided that the above copyright notice appears in all
40 copies and that both the copyright notice and this permission notice
41 appear in supporting documentation, and that the name of Intel
42 not be used in advertising or publicity pertaining to distribution
43 of the software without specific, written prior permission.
45 INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
46 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
47 IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
48 CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
49 LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
50 NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
51 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
55 * Serial bootblock interface routines
56 * Copyright (c) 1994, J"org Wunsch
58 * Permission to use, copy, modify and distribute this software and its
59 * documentation is hereby granted, provided that both the copyright
60 * notice and this permission notice appear in all copies of the
61 * software, derivative works or modified versions, and any portions
62 * thereof, and that both notices appear in supporting documentation.
64 * THE AUTHOR ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
65 * CONDITION. THE AUTHOR DISCLAIMS ANY LIABILITY OF ANY KIND FOR
66 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
70 * modified for PC-98 by KATO T. of Nagoya University
75 #include <isa/sioreg.h>
81 * The serial port interface routines implement a simple polled i/o
82 * interface to a standard serial port. Due to the space restrictions
83 * for the boot blocks, no BIOS support is used (since BIOS requires
84 * expensive real/protected mode switches), instead the rudimentary
85 * BIOS support is duplicated here.
87 * The base address for the i/o port is passed from the Makefile in
88 * the COMCONSOLE preprocessor macro. Console parameters are currently
89 * hard-coded to 9600 Bd, 8 bit. This can be changed in the
90 * init_serial() function.
94 * void serial_putc(char ch)
95 * send ch to serial port
100 mov $COMCONSOLE + 2, %edx # line status reg
103 jz 1b # TX buffer not empty
107 sub $2, %edx # TX output reg
108 outb %al, %dx # send this one
113 * int serial_getc(void)
114 * read a character from serial port
118 mov $COMCONSOLE + 2, %edx # line status reg
122 jz 1b # no RX char available
125 subb $2, %edx # RX buffer reg
126 inb %dx, %al # fetch (first) character
128 cmp $0x7F, %eax # make DEL...
130 movb $0x08, %eax # look like BS
135 * int serial_ischar(void)
136 * if there is a character pending, return true; otherwise return 0
140 movl $COMCONSOLE + 2, %edx # line status reg
142 andb $0x02, %al # RX char available?
147 * void init_serial(void)
148 * initialize the serial console port to 9600 Bd, 8 bpc
154 movl $COMCONSOLE_CLK, %eax
160 /* inhibit com int */
174 movl $COMCONSOLE + 2, %edx
188 movb $COMCONSOLE_MODE , %al
190 orb $0x02, %al /* factor = 1/16 */