1 /* $NetBSD: cninit.c,v 1.3 1998/06/21 22:36:46 tv Exp $ */ 2 3 /* 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * from: Utah $Hdr: cons.c 1.7 92/01/21$ 41 * 42 * @(#)cons.c 8.2 (Berkeley) 1/12/94 43 */ 44 45 #include <sys/param.h> 46 #include <sys/proc.h> 47 #include <sys/user.h> 48 #include <sys/systm.h> 49 #include <sys/buf.h> 50 #include <sys/ioctl.h> 51 #include <sys/tty.h> 52 #include <sys/file.h> 53 #include <sys/conf.h> 54 #include <sys/vnode.h> 55 56 #include <dev/cons.h> 57 58 extern struct consdev constab[]; 59 60 extern struct consdev *cn_tab; /* physical console device info */ 61 62 void 63 cninit() 64 { 65 struct consdev *cp; 66 struct consdev *bestMatch; 67 68 bestMatch = cn_tab = NULL; 69 /* 70 * Collect information about all possible consoles 71 * and find the one with highest priority 72 */ 73 for (cp = constab; cp->cn_probe; cp++) { 74 (*cp->cn_probe)(cp); 75 if (cp->cn_pri > CN_DEAD && 76 (bestMatch == NULL || cp->cn_pri > bestMatch->cn_pri)) { 77 bestMatch = cp; 78 } 79 } 80 /* 81 * No console, we can handle it 82 */ 83 if ((cp = bestMatch) == NULL) 84 return; 85 /* 86 * Turn on console 87 */ 88 { 89 struct consdev *old_cn_tab = cn_tab; 90 91 (*cp->cn_init)(cp); 92 /* 93 * Now let everyone know we have an active console they can 94 * use for diagnostics. If we use cn_tab in the search loop 95 * then interrupts from the ethernet at boot may cause system 96 * hang. 97 */ 98 if (cn_tab == old_cn_tab) 99 cn_tab = bestMatch; 100 } 101 } 102