config root man

/*-
 * Copyright (c) 1991 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * William Jolitz.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	from: @(#)isa.c	7.2 (Berkeley) 5/13/91
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/x86/isa/nmi.c 204309 2010-02-25 14:13:39Z attilio $");

#include "opt_mca.h"

#include <sys/types.h>
#include <sys/syslog.h>
#include <sys/systm.h>

#include <machine/md_var.h>

#ifdef DEV_MCA
#include <i386/bios/mca_machdep.h>
#endif

#define NMI_PARITY (1 << 7)
#define NMI_IOCHAN (1 << 6)
#define ENMI_WATCHDOG (1 << 7)
#define ENMI_BUSTIMER (1 << 6)
#define ENMI_IOSTATUS (1 << 5)

/*
 * Handle a NMI, possibly a machine check.
 * return true to panic system, false to ignore.
 */
int
isa_nmi(int cd)
{
	int retval = 0;
	int isa_port = inb(0x61);
	int eisa_port = inb(0x461);

	log(LOG_CRIT, "NMI ISA %x, EISA %x\n", isa_port, eisa_port);
#ifdef DEV_MCA
	if (MCA_system && mca_bus_nmi())
		return(0);
#endif
	
	if (isa_port & NMI_PARITY) {
		log(LOG_CRIT, "RAM parity error, likely hardware failure.");
		retval = 1;
	}

	if (isa_port & NMI_IOCHAN) {
		log(LOG_CRIT, "I/O channel check, likely hardware failure.");
		retval = 1;
	}

	/*
	 * On a real EISA machine, this will never happen.  However it can
	 * happen on ISA machines which implement XT style floating point
	 * error handling (very rare).  Save them from a meaningless panic.
	 */
	if (eisa_port == 0xff)
		return(retval);

	if (eisa_port & ENMI_WATCHDOG) {
		log(LOG_CRIT, "EISA watchdog timer expired, likely hardware failure.");
		retval = 1;
	}

	if (eisa_port & ENMI_BUSTIMER) {
		log(LOG_CRIT, "EISA bus timeout, likely hardware failure.");
		retval = 1;
	}

	if (eisa_port & ENMI_IOSTATUS) {
		log(LOG_CRIT, "EISA I/O port status error.");
		retval = 1;
	}

	return(retval);
}