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 $
31 Copyright 1988, 1989, 1990, 1991, 1992
32 by Intel Corporation, Santa Clara, California.
36 Permission to use, copy, modify, and distribute this software and
37 its documentation for any purpose and without fee is hereby
38 granted, provided that the above copyright notice appears in all
39 copies and that both the copyright notice and this permission notice
40 appear in supporting documentation, and that the name of Intel
41 not be used in advertising or publicity pertaining to distribution
42 of the software without specific, written prior permission.
44 INTEL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
45 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS,
46 IN NO EVENT SHALL INTEL BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
47 CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
48 LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
49 NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
50 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
54 * Serial bootblock interface routines
55 * Copyright (c) 1994, J"org Wunsch
57 * Permission to use, copy, modify and distribute this software and its
58 * documentation is hereby granted, provided that both the copyright
59 * notice and this permission notice appear in all copies of the
60 * software, derivative works or modified versions, and any portions
61 * thereof, and that both notices appear in supporting documentation.
63 * THE AUTHOR ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
64 * CONDITION. THE AUTHOR DISCLAIMS ANY LIABILITY OF ANY KIND FOR
65 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
69 * modified for PC-98 by KATO T. of Nagoya University
74 #include <isa/sioreg.h>
80 * The serial port interface routines implement a simple polled i/o
81 * interface to a standard serial port. Due to the space restrictions
82 * for the boot blocks, no BIOS support is used (since BIOS requires
83 * expensive real/protected mode switches), instead the rudimentary
84 * BIOS support is duplicated here.
86 * The base address for the i/o port is passed from the Makefile in
87 * the COMCONSOLE preprocessor macro. Console parameters are currently
88 * hard-coded to 9600 Bd, 8 bit. This can be changed in the
89 * init_serial() function.
93 * void serial_putc(char ch)
94 * send ch to serial port
99 mov $COMCONSOLE + 2, %edx # line status reg
102 jz 1b # TX buffer not empty
106 sub $2, %edx # TX output reg
107 outb %al, %dx # send this one
112 * int serial_getc(void)
113 * read a character from serial port
117 mov $COMCONSOLE + 2, %edx # line status reg
121 jz 1b # no RX char available
124 subb $2, %edx # RX buffer reg
125 inb %dx, %al # fetch (first) character
127 cmp $0x7F, %eax # make DEL...
129 movb $0x08, %eax # look like BS
134 * int serial_ischar(void)
135 * if there is a character pending, return true; otherwise return 0
139 movl $COMCONSOLE + 2, %edx # line status reg
141 andb $0x02, %al # RX char available?
146 * void init_serial(void)
147 * initialize the serial console port to 9600 Bd, 8 bpc
153 movl $COMCONSOLE_CLK, %eax
159 /* inhibit com int */
173 movl $COMCONSOLE + 2, %edx
187 movb $COMCONSOLE_MODE , %al
189 orb $0x02, %al /* factor = 1/16 */