xref: /original-bsd/sys/i386/i386/autoconf.c (revision bbb96de4)
1 /*-
2  * Copyright (c) 1990 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * William Jolitz.
7  *
8  * %sccs.include.386.c%
9  *
10  *	@(#)autoconf.c	5.2 (Berkeley) 06/23/90
11  */
12 
13 /*	autoconf.c	1.13	87/04/02	*/
14 
15 /*
16  * Setup the system to run on the current machine.
17  *
18  * Configure() is called at boot time and initializes the vba
19  * device tables and the memory controller monitoring.  Available
20  * devices are determined (from possibilities mentioned in ioconf.c),
21  * and the drivers are initialized.
22  */
23 #include "param.h"
24 #include "systm.h"
25 #include "map.h"
26 #include "buf.h"
27 #include "dkstat.h"
28 #include "vm.h"
29 #include "conf.h"
30 #include "dmap.h"
31 #include "reboot.h"
32 
33 #include "pte.h"
34 #include "../machine/device.h"
35 
36 /*
37  * The following several variables are related to
38  * the configuration process, and are used in initializing
39  * the machine.
40  */
41 int	dkn;		/* number of iostat dk numbers assigned so far */
42 int	cold;		/* cold start flag initialized in locore.s */
43 
44 /*
45  * Determine i/o configuration for a machine.
46  */
47 configure()
48 {
49 	register int *ip;
50 	extern caddr_t Sysbase;
51 	struct device *dvp;
52 	struct driver *dp;
53 	register s;
54 
55 	for (dvp = devtab; dp = dvp->driver; dvp++) {
56 		s = splhigh();
57 		dvp->alive = (*dp->probe)(dvp);
58 		if (dvp->alive) {
59 			printf("%s%d", dp->name, dvp->unit);
60 			(*dp->attach)(dvp);
61 			printf(" at 0x%x on isa0\n", dvp->ioa);
62 		}
63 		splx(s);
64 	}
65 
66 /*pg("setroot");*/
67 #if GENERICxxx
68 	if ((boothowto & RB_ASKNAME) == 0)
69 		setroot();
70 	setconf();
71 #else
72 	setroot();
73 #endif
74 	/*
75 	 * Configure swap area and related system
76 	 * parameter based on device(s) used.
77 	 */
78 /*pg("swapconf");*/
79 	swapconf();
80 	cold = 0;
81 }
82 
83 /*
84  * Configure swap space and related parameters.
85  */
86 swapconf()
87 {
88 	register struct swdevt *swp;
89 	register int nblks;
90 
91 	for (swp = swdevt; swp->sw_dev > 0; swp++)
92 	{
93 		if ( swp->sw_dev < 0 || swp->sw_dev > nblkdev ) break;
94 		if (bdevsw[major(swp->sw_dev)].d_psize) {
95 			nblks =
96 			  (*bdevsw[major(swp->sw_dev)].d_psize)(swp->sw_dev);
97 			if (nblks != -1 &&
98 			    (swp->sw_nblks == 0 || swp->sw_nblks > nblks))
99 				swp->sw_nblks = nblks;
100 		}
101 	}
102 	if (dumplo == 0 && bdevsw[major(dumpdev)].d_psize)
103 		dumplo = (*bdevsw[major(dumpdev)].d_psize)(dumpdev) - physmem;
104 	if (dumplo < 0)
105 		dumplo = 0;
106 }
107 
108 #define	DOSWAP			/* change swdevt, argdev, and dumpdev too */
109 u_long	bootdev;		/* should be dev_t, but not until 32 bits */
110 
111 static	char devname[][2] = {
112 	0,0,		/* 0 = ud */
113 	'd','k',	/* 1 = vd */
114 	0,0,		/* 2 = xp */
115 };
116 
117 #define	PARTITIONMASK	0x7
118 #define	PARTITIONSHIFT	3
119 
120 /*
121  * Attempt to find the device from which we were booted.
122  * If we can do so, and not instructed not to do so,
123  * change rootdev to correspond to the load device.
124  */
125 setroot()
126 {
127 	int  majdev, mindev, unit, part, adaptor;
128 	dev_t temp, orootdev;
129 	struct swdevt *swp;
130 
131 	if (boothowto & RB_DFLTROOT ||
132 	    (bootdev & B_MAGICMASK) != (u_long)B_DEVMAGIC)
133 		return;
134 	majdev = (bootdev >> B_TYPESHIFT) & B_TYPEMASK;
135 	if (majdev > sizeof(devname) / sizeof(devname[0]))
136 		return;
137 	adaptor = (bootdev >> B_ADAPTORSHIFT) & B_ADAPTORMASK;
138 	part = (bootdev >> B_PARTITIONSHIFT) & B_PARTITIONMASK;
139 	unit = (bootdev >> B_UNITSHIFT) & B_UNITMASK;
140 	mindev = (mindev << PARTITIONSHIFT) + part;
141 	orootdev = rootdev;
142 	rootdev = makedev(majdev, mindev);
143 	/*
144 	 * If the original rootdev is the same as the one
145 	 * just calculated, don't need to adjust the swap configuration.
146 	 */
147 	if (rootdev == orootdev)
148 		return;
149 	printf("changing root device to %c%c%d%c\n",
150 		devname[majdev][0], devname[majdev][1],
151 		mindev >> PARTITIONSHIFT, part + 'a');
152 #ifdef DOSWAP
153 	mindev &= ~PARTITIONMASK;
154 	for (swp = swdevt; swp->sw_dev; swp++) {
155 		if (majdev == major(swp->sw_dev) &&
156 		    mindev == (minor(swp->sw_dev) & ~PARTITIONMASK)) {
157 			temp = swdevt[0].sw_dev;
158 			swdevt[0].sw_dev = swp->sw_dev;
159 			swp->sw_dev = temp;
160 			break;
161 		}
162 	}
163 	if (swp->sw_dev == 0)
164 		return;
165 	/*
166 	 * If argdev and dumpdev were the same as the old primary swap
167 	 * device, move them to the new primary swap device.
168 	 */
169 	if (temp == dumpdev)
170 		dumpdev = swdevt[0].sw_dev;
171 	if (temp == argdev)
172 		argdev = swdevt[0].sw_dev;
173 #endif
174 }
175