/*      $NetBSD: cninit.c,v 1.14 2020/07/29 01:55:58 uwe Exp $  */

/*
 * Copyright (c) 1988 University of Utah.
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * 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.
 * 3. 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: Utah $Hdr: cons.c 1.7 92/01/21$
 *
 *      @(#)cons.c      8.2 (Berkeley) 1/12/94
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cninit.c,v 1.14 2020/07/29 01:55:58 uwe Exp $");

#include <sys/param.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/file.h>
#include <sys/conf.h>
#include <sys/vnode.h>

#include <dev/cons.h>

void
cninit(void)
{
        struct consdev *bestMatch;
        struct consdev *cp;

        /*
         * Collect information about all possible consoles
         * and find the one with highest priority
         */
        bestMatch = NULL;
        for (cp = constab; cp->cn_probe; cp++) {
                (*cp->cn_probe)(cp);
                if (cp->cn_pri > CN_DEAD &&
                    (bestMatch == NULL || cp->cn_pri > bestMatch->cn_pri)) {
                        bestMatch = cp;
                }
        }

        /*
         * No console, we can handle it
         */
        if (bestMatch == NULL)
                return;

        /*
         * Turn on console
         */
        {
                struct consdev *old_cn_tab = cn_tab;

                /* cn_init may set cn_tab to self */
                (*bestMatch->cn_init)(bestMatch);

                /*
                 * Now let everyone know we have an active console they can
                 * use for diagnostics. If we use cn_tab in the search loop
                 * then interrupts from the ethernet at boot may cause system
                 * hang.
                 */
                if (cn_tab == old_cn_tab) /* if cn_init didn't, set it */
                        cn_tab = bestMatch;
        }
}