xref: /freebsd/sys/x86/isa/nmi.c (revision 4d65a7c6951cea0333f1a0c1b32c38489cdfa6c5)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1991 The Regents of the University of California.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * William Jolitz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/syslog.h>
37 #include <sys/systm.h>
38 
39 #include <machine/md_var.h>
40 
41 #define NMI_PARITY (1 << 7)
42 #define NMI_IOCHAN (1 << 6)
43 #define ENMI_WATCHDOG (1 << 7)
44 #define ENMI_BUSTIMER (1 << 6)
45 #define ENMI_IOSTATUS (1 << 5)
46 
47 /*
48  * Handle a NMI, possibly a machine check.
49  * return true to panic system, false to ignore.
50  */
51 int
52 isa_nmi(int cd)
53 {
54 	int retval = 0;
55 	int isa_port = inb(0x61);
56 	int eisa_port = inb(0x461);
57 
58 	log(LOG_CRIT, "NMI ISA %x, EISA %x\n", isa_port, eisa_port);
59 
60 	if (isa_port & NMI_PARITY) {
61 		log(LOG_CRIT, "RAM parity error, likely hardware failure.");
62 		retval = 1;
63 	}
64 
65 	if (isa_port & NMI_IOCHAN) {
66 		log(LOG_CRIT, "I/O channel check, likely hardware failure.");
67 		retval = 1;
68 	}
69 
70 	/*
71 	 * On a real EISA machine, this will never happen.  However it can
72 	 * happen on ISA machines which implement XT style floating point
73 	 * error handling (very rare).  Save them from a meaningless panic.
74 	 */
75 	if (eisa_port == 0xff)
76 		return(retval);
77 
78 	if (eisa_port & ENMI_WATCHDOG) {
79 		log(LOG_CRIT, "EISA watchdog timer expired, likely hardware failure.");
80 		retval = 1;
81 	}
82 
83 	if (eisa_port & ENMI_BUSTIMER) {
84 		log(LOG_CRIT, "EISA bus timeout, likely hardware failure.");
85 		retval = 1;
86 	}
87 
88 	if (eisa_port & ENMI_IOSTATUS) {
89 		log(LOG_CRIT, "EISA I/O port status error.");
90 		retval = 1;
91 	}
92 
93 	return(retval);
94 }
95