xref: /src/sys/arch/alpha/alpha/autoconf.c

/*	$NetBSD: autoconf.c,v 1.2 1996/04/04 06:25:00 cgd Exp $	*/

/*
 * Copyright (c) 1994, 1995 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Authors: Keith Bostic, Chris G. Demetriou
 *
 * Permission to use, copy, modify and distribute this software and
 * its documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/disklabel.h>
#include <sys/conf.h>
#include <sys/reboot.h>
#include <sys/device.h>

#include <machine/autoconf.h>

/*
 * configure:
 * called at boot time, configure all devices on system
 */
void
configure()
{
	extern int cold;

	(void)splhigh();
	if (config_rootfound("mainbus", "mainbus") == NULL)
		panic("no mainbus found");
	(void)spl0();

#ifdef GENERIC
	if ((boothowto & RB_ASKNAME) == 0)
		setroot();
	setconf();
#else
	setroot();
#endif
	swapconf();
	cold = 0;
}

/*
 * Configure swap space and related parameters.
 */
swapconf()
{
	register struct swdevt *swp;
	register int nblks;

	for (swp = swdevt; swp->sw_dev != NODEV; swp++) {
		int maj = major(swp->sw_dev);

		if (maj > nblkdev)
			break;
		if (bdevsw[maj].d_psize) {
			nblks = (*bdevsw[maj].d_psize)(swp->sw_dev);
			if (nblks != -1 &&
			    (swp->sw_nblks == 0 || swp->sw_nblks > nblks))
				swp->sw_nblks = nblks;
			swp->sw_nblks = ctod(dtoc(swp->sw_nblks));
		}
	}
}

#define	DOSWAP			/* change swdevt and dumpdev */
dev_t	bootdev = 0;		/* should be dev_t, but not until 32 bits */

static	char devname[][2] = {
	'x','x',	/* 0 = XX */
	'x','x',	/* 1 = XX */
	'x','x',	/* 2 = XX */
	'x','x',	/* 3 = XX */
	'x','x',	/* 4 = XX */
	'x','x',	/* 5 = XX */
	'x','x',	/* 6 = XX */
	'x','x',	/* 7 = XX */
	's','d',	/* 8 = sd */
};

/*
 * Attempt to find the device from which we were booted.
 * If we can do so, and not instructed not to do so,
 * change rootdev to correspond to the load device.
 */
setroot()
{
	int  majdev, mindev, unit, part, adaptor;
	dev_t temp, orootdev;
	struct swdevt *swp;

/*printf("howto %x bootdev %x ", boothowto, bootdev);*/
	if (boothowto & RB_DFLTROOT ||
	    (bootdev & B_MAGICMASK) != (u_long)B_DEVMAGIC)
		return;
	majdev = (bootdev >> B_TYPESHIFT) & B_TYPEMASK;
	if (majdev > sizeof(devname) / sizeof(devname[0]))
		return;
	adaptor = (bootdev >> B_ADAPTORSHIFT) & B_ADAPTORMASK;
	part = (bootdev >> B_PARTITIONSHIFT) & B_PARTITIONMASK;
	unit = (bootdev >> B_UNITSHIFT) & B_UNITMASK;
	mindev = (unit * MAXPARTITIONS) + part;
	orootdev = rootdev;
	rootdev = makedev(majdev, mindev);
	/*
	 * If the original rootdev is the same as the one
	 * just calculated, don't need to adjust the swap configuration.
	 */
	if (rootdev == orootdev)
		return;
	printf("changing root device to %c%c%d%c\n",
		devname[majdev][0], devname[majdev][1],
		unit, part + 'a');

#ifdef DOSWAP
	for (swp = swdevt; swp->sw_dev != NODEV; swp++) {
		if (majdev == major(swp->sw_dev) &&
		    (mindev / MAXPARTITIONS)
		    == (minor(swp->sw_dev) / MAXPARTITIONS)) {
			temp = swdevt[0].sw_dev;
			swdevt[0].sw_dev = swp->sw_dev;
			swp->sw_dev = temp;
			break;
		}
	}
	if (swp->sw_dev == NODEV)
		return;

	/*
	 * If dumpdev was the same as the old primary swap device, move
	 * it to the new primary swap device.
	 */
	if (temp == dumpdev)
		dumpdev = swdevt[0].sw_dev;
#endif
}