xref: /netbsd/sys/kern/subr_autoconf.c (revision c4a72b64)
1 /* $NetBSD: subr_autoconf.c,v 1.79 2002/11/24 17:33:44 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 1996, 2000 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *          This product includes software developed for the
18  *          NetBSD Project.  See http://www.netbsd.org/ for
19  *          information about NetBSD.
20  * 4. The name of the author may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  *
34  * --(license Id: LICENSE.proto,v 1.1 2000/06/13 21:40:26 cgd Exp )--
35  */
36 
37 /*
38  * Copyright (c) 1992, 1993
39  *	The Regents of the University of California.  All rights reserved.
40  *
41  * This software was developed by the Computer Systems Engineering group
42  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
43  * contributed to Berkeley.
44  *
45  * All advertising materials mentioning features or use of this software
46  * must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Lawrence Berkeley Laboratories.
49  *
50  * Redistribution and use in source and binary forms, with or without
51  * modification, are permitted provided that the following conditions
52  * are met:
53  * 1. Redistributions of source code must retain the above copyright
54  *    notice, this list of conditions and the following disclaimer.
55  * 2. Redistributions in binary form must reproduce the above copyright
56  *    notice, this list of conditions and the following disclaimer in the
57  *    documentation and/or other materials provided with the distribution.
58  * 3. All advertising materials mentioning features or use of this software
59  *    must display the following acknowledgement:
60  *	This product includes software developed by the University of
61  *	California, Berkeley and its contributors.
62  * 4. Neither the name of the University nor the names of its contributors
63  *    may be used to endorse or promote products derived from this software
64  *    without specific prior written permission.
65  *
66  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
67  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
68  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
69  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
70  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
71  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
72  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
73  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
74  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
75  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
76  * SUCH DAMAGE.
77  *
78  * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp  (LBL)
79  *
80  *	@(#)subr_autoconf.c	8.3 (Berkeley) 5/17/94
81  */
82 
83 #include <sys/cdefs.h>
84 __KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.79 2002/11/24 17:33:44 thorpej Exp $");
85 
86 #include "opt_ddb.h"
87 
88 #include <sys/param.h>
89 #include <sys/device.h>
90 #include <sys/malloc.h>
91 #include <sys/systm.h>
92 #include <sys/kernel.h>
93 #include <sys/errno.h>
94 #include <sys/proc.h>
95 #include <machine/limits.h>
96 
97 #include "opt_userconf.h"
98 #ifdef USERCONF
99 #include <sys/userconf.h>
100 #include <sys/reboot.h>
101 #endif
102 
103 /*
104  * Autoconfiguration subroutines.
105  */
106 
107 /*
108  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
109  * devices and drivers are found via these tables.
110  */
111 extern struct cfdata cfdata[];
112 extern short cfroots[];
113 
114 /*
115  * List of all cfdriver structures.  We use this to detect duplicates
116  * when other cfdrivers are loaded.
117  */
118 struct cfdriverlist allcfdrivers = LIST_HEAD_INITIALIZER(&allcfdrivers);
119 extern struct cfdriver * const cfdriver_list_initial[];
120 
121 /*
122  * Initial list of cfattach's.
123  */
124 extern const struct cfattachinit cfattachinit[];
125 
126 /*
127  * List of cfdata tables.  We always have one such list -- the one
128  * built statically when the kernel was configured.
129  */
130 struct cftablelist allcftables;
131 static struct cftable initcftable;
132 
133 #define	ROOT ((struct device *)NULL)
134 
135 struct matchinfo {
136 	cfmatch_t fn;
137 	struct	device *parent;
138 	void	*aux;
139 	struct	cfdata *match;
140 	int	pri;
141 };
142 
143 static char *number(char *, int);
144 static void mapply(struct matchinfo *, struct cfdata *);
145 
146 struct deferred_config {
147 	TAILQ_ENTRY(deferred_config) dc_queue;
148 	struct device *dc_dev;
149 	void (*dc_func)(struct device *);
150 };
151 
152 TAILQ_HEAD(deferred_config_head, deferred_config);
153 
154 struct deferred_config_head deferred_config_queue;
155 struct deferred_config_head interrupt_config_queue;
156 
157 static void config_process_deferred(struct deferred_config_head *,
158 	struct device *);
159 
160 /* Hooks to finalize configuration once all real devices have been found. */
161 struct finalize_hook {
162 	TAILQ_ENTRY(finalize_hook) f_list;
163 	int (*f_func)(struct device *);
164 	struct device *f_dev;
165 };
166 static TAILQ_HEAD(, finalize_hook) config_finalize_list;
167 static int config_finalize_done;
168 
169 /* list of all devices */
170 struct devicelist alldevs;
171 
172 /* list of all events */
173 struct evcntlist allevents = TAILQ_HEAD_INITIALIZER(allevents);
174 
175 __volatile int config_pending;		/* semaphore for mountroot */
176 
177 #define	STREQ(s1, s2)			\
178 	(*(s1) == *(s2) && strcmp((s1), (s2)) == 0)
179 
180 static int config_initialized;		/* config_init() has been called. */
181 
182 /*
183  * Initialize the autoconfiguration data structures.  Normally this
184  * is done by configure(), but some platforms need to do this very
185  * early (to e.g. initialize the console).
186  */
187 void
188 config_init(void)
189 {
190 	const struct cfattachinit *cfai;
191 	int i, j;
192 
193 	if (config_initialized)
194 		return;
195 
196 	/* allcfdrivers is statically initialized. */
197 	for (i = 0; cfdriver_list_initial[i] != NULL; i++) {
198 		if (config_cfdriver_attach(cfdriver_list_initial[i]) != 0)
199 			panic("configure: duplicate `%s' drivers",
200 			    cfdriver_list_initial[i]->cd_name);
201 	}
202 
203 	for (cfai = &cfattachinit[0]; cfai->cfai_name != NULL; cfai++) {
204 		for (j = 0; cfai->cfai_list[j] != NULL; j++) {
205 			if (config_cfattach_attach(cfai->cfai_name,
206 						   cfai->cfai_list[j]) != 0)
207 				panic("configure: duplicate `%s' attachment "
208 				    "of `%s' driver",
209 				    cfai->cfai_list[j]->ca_name,
210 				    cfai->cfai_name);
211 		}
212 	}
213 
214 	TAILQ_INIT(&allcftables);
215 	initcftable.ct_cfdata = cfdata;
216 	TAILQ_INSERT_TAIL(&allcftables, &initcftable, ct_list);
217 
218 	TAILQ_INIT(&deferred_config_queue);
219 	TAILQ_INIT(&interrupt_config_queue);
220 	TAILQ_INIT(&config_finalize_list);
221 	TAILQ_INIT(&alldevs);
222 
223 	config_initialized = 1;
224 }
225 
226 /*
227  * Configure the system's hardware.
228  */
229 void
230 configure(void)
231 {
232 
233 	/* Initialize data structures. */
234 	config_init();
235 
236 #ifdef USERCONF
237 	if (boothowto & RB_USERCONF)
238 		user_config();
239 #endif
240 
241 	/*
242 	 * Do the machine-dependent portion of autoconfiguration.  This
243 	 * sets the configuration machinery here in motion by "finding"
244 	 * the root bus.  When this function returns, we expect interrupts
245 	 * to be enabled.
246 	 */
247 	cpu_configure();
248 
249 	/*
250 	 * Now that we've found all the hardware, start the real time
251 	 * and statistics clocks.
252 	 */
253 	initclocks();
254 
255 	cold = 0;	/* clocks are running, we're warm now! */
256 
257 	/*
258 	 * Now callback to finish configuration for devices which want
259 	 * to do this once interrupts are enabled.
260 	 */
261 	config_process_deferred(&interrupt_config_queue, NULL);
262 }
263 
264 /*
265  * Add a cfdriver to the system.
266  */
267 int
268 config_cfdriver_attach(struct cfdriver *cd)
269 {
270 	struct cfdriver *lcd;
271 
272 	/* Make sure this driver isn't already in the system. */
273 	LIST_FOREACH(lcd, &allcfdrivers, cd_list) {
274 		if (STREQ(lcd->cd_name, cd->cd_name))
275 			return (EEXIST);
276 	}
277 
278 	LIST_INIT(&cd->cd_attach);
279 	LIST_INSERT_HEAD(&allcfdrivers, cd, cd_list);
280 
281 	return (0);
282 }
283 
284 /*
285  * Remove a cfdriver from the system.
286  */
287 int
288 config_cfdriver_detach(struct cfdriver *cd)
289 {
290 	int i;
291 
292 	/* Make sure there are no active instances. */
293 	for (i = 0; i < cd->cd_ndevs; i++) {
294 		if (cd->cd_devs[i] != NULL)
295 			return (EBUSY);
296 	}
297 
298 	/* ...and no attachments loaded. */
299 	if (LIST_EMPTY(&cd->cd_attach) == 0)
300 		return (EBUSY);
301 
302 	LIST_REMOVE(cd, cd_list);
303 
304 	KASSERT(cd->cd_devs == NULL);
305 
306 	return (0);
307 }
308 
309 /*
310  * Look up a cfdriver by name.
311  */
312 struct cfdriver *
313 config_cfdriver_lookup(const char *name)
314 {
315 	struct cfdriver *cd;
316 
317 	LIST_FOREACH(cd, &allcfdrivers, cd_list) {
318 		if (STREQ(cd->cd_name, name))
319 			return (cd);
320 	}
321 
322 	return (NULL);
323 }
324 
325 /*
326  * Add a cfattach to the specified driver.
327  */
328 int
329 config_cfattach_attach(const char *driver, struct cfattach *ca)
330 {
331 	struct cfattach *lca;
332 	struct cfdriver *cd;
333 
334 	cd = config_cfdriver_lookup(driver);
335 	if (cd == NULL)
336 		return (ESRCH);
337 
338 	/* Make sure this attachment isn't already on this driver. */
339 	LIST_FOREACH(lca, &cd->cd_attach, ca_list) {
340 		if (STREQ(lca->ca_name, ca->ca_name))
341 			return (EEXIST);
342 	}
343 
344 	LIST_INSERT_HEAD(&cd->cd_attach, ca, ca_list);
345 
346 	return (0);
347 }
348 
349 /*
350  * Remove a cfattach from the specified driver.
351  */
352 int
353 config_cfattach_detach(const char *driver, struct cfattach *ca)
354 {
355 	struct cfdriver *cd;
356 	struct device *dev;
357 	int i;
358 
359 	cd = config_cfdriver_lookup(driver);
360 	if (cd == NULL)
361 		return (ESRCH);
362 
363 	/* Make sure there are no active instances. */
364 	for (i = 0; i < cd->cd_ndevs; i++) {
365 		if ((dev = cd->cd_devs[i]) == NULL)
366 			continue;
367 		if (dev->dv_cfattach == ca)
368 			return (EBUSY);
369 	}
370 
371 	LIST_REMOVE(ca, ca_list);
372 
373 	return (0);
374 }
375 
376 /*
377  * Look up a cfattach by name.
378  */
379 static struct cfattach *
380 config_cfattach_lookup_cd(struct cfdriver *cd, const char *atname)
381 {
382 	struct cfattach *ca;
383 
384 	LIST_FOREACH(ca, &cd->cd_attach, ca_list) {
385 		if (STREQ(ca->ca_name, atname))
386 			return (ca);
387 	}
388 
389 	return (NULL);
390 }
391 
392 /*
393  * Look up a cfattach by driver/attachment name.
394  */
395 struct cfattach *
396 config_cfattach_lookup(const char *name, const char *atname)
397 {
398 	struct cfdriver *cd;
399 
400 	cd = config_cfdriver_lookup(name);
401 	if (cd == NULL)
402 		return (NULL);
403 
404 	return (config_cfattach_lookup_cd(cd, atname));
405 }
406 
407 /*
408  * Apply the matching function and choose the best.  This is used
409  * a few times and we want to keep the code small.
410  */
411 static void
412 mapply(struct matchinfo *m, struct cfdata *cf)
413 {
414 	int pri;
415 
416 	if (m->fn != NULL)
417 		pri = (*m->fn)(m->parent, cf, m->aux);
418 	else {
419 		struct cfattach *ca;
420 
421 		ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
422 		if (ca == NULL) {
423 			/* No attachment for this entry, oh well. */
424 			return;
425 		}
426 	        if (ca->ca_match == NULL) {
427 			panic("mapply: no match function for '%s' attachment "
428 			    "of '%s'", cf->cf_atname, cf->cf_name);
429 		}
430 		pri = (*ca->ca_match)(m->parent, cf, m->aux);
431 	}
432 	if (pri > m->pri) {
433 		m->match = cf;
434 		m->pri = pri;
435 	}
436 }
437 
438 /*
439  * Determine if `parent' is a potential parent for a device spec based
440  * on `cfp'.
441  */
442 static int
443 cfparent_match(struct device *parent, const struct cfparent *cfp)
444 {
445 	struct cfdriver *pcd;
446 	const char * const *cpp;
447 	const char *cp;
448 
449 	/* We don't match root nodes here. */
450 	if (cfp == NULL)
451 		return (0);
452 
453 	pcd = parent->dv_cfdriver;
454 	KASSERT(pcd != NULL);
455 
456 	/*
457 	 * First, ensure this parent has the correct interface
458 	 * attribute.
459 	 */
460 	if (pcd->cd_attrs == NULL)
461 		return (0);	/* no interface attributes -> no children */
462 	for (cpp = pcd->cd_attrs; (cp = *cpp) != NULL; cpp++) {
463 		if (STREQ(cp, cfp->cfp_iattr)) {
464 			/* Match. */
465 			break;
466 		}
467 	}
468 	if (cp == NULL)
469 		return (0);	/* doesn't carry the req'd attribute */
470 
471 	/*
472 	 * If no specific parent device instance was specified (i.e.
473 	 * we're attaching to the attribute only), we're done!
474 	 */
475 	if (cfp->cfp_parent == NULL)
476 		return (1);
477 
478 	/*
479 	 * Check the parent device's name.
480 	 */
481 	if (STREQ(pcd->cd_name, cfp->cfp_parent) == 0)
482 		return (0);	/* not the same parent */
483 
484 	/*
485 	 * Make sure the unit number matches.
486 	 */
487 	if (cfp->cfp_unit == DVUNIT_ANY ||	/* wildcard */
488 	    cfp->cfp_unit == parent->dv_unit)
489 		return (1);
490 
491 	/* Unit numbers don't match. */
492 	return (0);
493 }
494 
495 /*
496  * Invoke the "match" routine for a cfdata entry on behalf of
497  * an external caller, usually a "submatch" routine.
498  */
499 int
500 config_match(struct device *parent, struct cfdata *cf, void *aux)
501 {
502 	struct cfattach *ca;
503 
504 	ca = config_cfattach_lookup(cf->cf_name, cf->cf_atname);
505 	if (ca == NULL) {
506 		/* No attachment for this entry, oh well. */
507 		return (0);
508 	}
509 
510 	return ((*ca->ca_match)(parent, cf, aux));
511 }
512 
513 /*
514  * Iterate over all potential children of some device, calling the given
515  * function (default being the child's match function) for each one.
516  * Nonzero returns are matches; the highest value returned is considered
517  * the best match.  Return the `found child' if we got a match, or NULL
518  * otherwise.  The `aux' pointer is simply passed on through.
519  *
520  * Note that this function is designed so that it can be used to apply
521  * an arbitrary function to all potential children (its return value
522  * can be ignored).
523  */
524 struct cfdata *
525 config_search(cfmatch_t fn, struct device *parent, void *aux)
526 {
527 	struct cftable *ct;
528 	struct cfdata *cf;
529 	struct matchinfo m;
530 
531 	KASSERT(config_initialized);
532 
533 	m.fn = fn;
534 	m.parent = parent;
535 	m.aux = aux;
536 	m.match = NULL;
537 	m.pri = 0;
538 
539 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
540 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
541 			/*
542 			 * Skip cf if no longer eligible, otherwise scan
543 			 * through parents for one matching `parent', and
544 			 * try match function.
545 			 */
546 			if (cf->cf_fstate == FSTATE_FOUND)
547 				continue;
548 			if (cf->cf_fstate == FSTATE_DNOTFOUND ||
549 			    cf->cf_fstate == FSTATE_DSTAR)
550 				continue;
551 			if (cfparent_match(parent, cf->cf_pspec))
552 				mapply(&m, cf);
553 		}
554 	}
555 	return (m.match);
556 }
557 
558 /*
559  * Find the given root device.
560  * This is much like config_search, but there is no parent.
561  * Don't bother with multiple cfdata tables; the root node
562  * must always be in the initial table.
563  */
564 struct cfdata *
565 config_rootsearch(cfmatch_t fn, const char *rootname, void *aux)
566 {
567 	struct cfdata *cf;
568 	short *p;
569 	struct matchinfo m;
570 
571 	m.fn = fn;
572 	m.parent = ROOT;
573 	m.aux = aux;
574 	m.match = NULL;
575 	m.pri = 0;
576 	/*
577 	 * Look at root entries for matching name.  We do not bother
578 	 * with found-state here since only one root should ever be
579 	 * searched (and it must be done first).
580 	 */
581 	for (p = cfroots; *p >= 0; p++) {
582 		cf = &cfdata[*p];
583 		if (strcmp(cf->cf_name, rootname) == 0)
584 			mapply(&m, cf);
585 	}
586 	return (m.match);
587 }
588 
589 static const char *msgs[3] = { "", " not configured\n", " unsupported\n" };
590 
591 /*
592  * The given `aux' argument describes a device that has been found
593  * on the given parent, but not necessarily configured.  Locate the
594  * configuration data for that device (using the submatch function
595  * provided, or using candidates' cd_match configuration driver
596  * functions) and attach it, and return true.  If the device was
597  * not configured, call the given `print' function and return 0.
598  */
599 struct device *
600 config_found_sm(struct device *parent, void *aux, cfprint_t print,
601     cfmatch_t submatch)
602 {
603 	struct cfdata *cf;
604 
605 	if ((cf = config_search(submatch, parent, aux)) != NULL)
606 		return (config_attach(parent, cf, aux, print));
607 	if (print)
608 		printf("%s", msgs[(*print)(aux, parent->dv_xname)]);
609 	return (NULL);
610 }
611 
612 /*
613  * As above, but for root devices.
614  */
615 struct device *
616 config_rootfound(const char *rootname, void *aux)
617 {
618 	struct cfdata *cf;
619 
620 	if ((cf = config_rootsearch((cfmatch_t)NULL, rootname, aux)) != NULL)
621 		return (config_attach(ROOT, cf, aux, (cfprint_t)NULL));
622 	printf("root device %s not configured\n", rootname);
623 	return (NULL);
624 }
625 
626 /* just like sprintf(buf, "%d") except that it works from the end */
627 static char *
628 number(char *ep, int n)
629 {
630 
631 	*--ep = 0;
632 	while (n >= 10) {
633 		*--ep = (n % 10) + '0';
634 		n /= 10;
635 	}
636 	*--ep = n + '0';
637 	return (ep);
638 }
639 
640 /*
641  * Expand the size of the cd_devs array if necessary.
642  */
643 void
644 config_makeroom(int n, struct cfdriver *cd)
645 {
646 	int old, new;
647 	void **nsp;
648 
649 	if (n < cd->cd_ndevs)
650 		return;
651 
652 	/*
653 	 * Need to expand the array.
654 	 */
655 	old = cd->cd_ndevs;
656 	if (old == 0)
657 		new = MINALLOCSIZE / sizeof(void *);
658 	else
659 		new = old * 2;
660 	while (new <= n)
661 		new *= 2;
662 	cd->cd_ndevs = new;
663 	nsp = malloc(new * sizeof(void *), M_DEVBUF,
664 	    cold ? M_NOWAIT : M_WAITOK);
665 	if (nsp == NULL)
666 		panic("config_attach: %sing dev array",
667 		    old != 0 ? "expand" : "creat");
668 	memset(nsp + old, 0, (new - old) * sizeof(void *));
669 	if (old != 0) {
670 		memcpy(nsp, cd->cd_devs, old * sizeof(void *));
671 		free(cd->cd_devs, M_DEVBUF);
672 	}
673 	cd->cd_devs = nsp;
674 }
675 
676 /*
677  * Attach a found device.  Allocates memory for device variables.
678  */
679 struct device *
680 config_attach(struct device *parent, struct cfdata *cf, void *aux,
681 	cfprint_t print)
682 {
683 	struct device *dev;
684 	struct cftable *ct;
685 	struct cfdriver *cd;
686 	struct cfattach *ca;
687 	size_t lname, lunit;
688 	const char *xunit;
689 	int myunit;
690 	char num[10];
691 
692 	cd = config_cfdriver_lookup(cf->cf_name);
693 	KASSERT(cd != NULL);
694 
695 	ca = config_cfattach_lookup_cd(cd, cf->cf_atname);
696 	KASSERT(ca != NULL);
697 
698 	if (ca->ca_devsize < sizeof(struct device))
699 		panic("config_attach");
700 
701 #ifndef __BROKEN_CONFIG_UNIT_USAGE
702 	if (cf->cf_fstate == FSTATE_STAR) {
703 		for (myunit = cf->cf_unit; myunit < cd->cd_ndevs; myunit++)
704 			if (cd->cd_devs[myunit] == NULL)
705 				break;
706 		/*
707 		 * myunit is now the unit of the first NULL device pointer,
708 		 * or max(cd->cd_ndevs,cf->cf_unit).
709 		 */
710 	} else {
711 		myunit = cf->cf_unit;
712 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
713 		cf->cf_fstate = FSTATE_FOUND;
714 	}
715 #else
716 	myunit = cf->cf_unit;
717 	if (cf->cf_fstate == FSTATE_STAR)
718 		cf->cf_unit++;
719 	else {
720 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
721 		cf->cf_fstate = FSTATE_FOUND;
722 	}
723 #endif /* ! __BROKEN_CONFIG_UNIT_USAGE */
724 
725 	/* compute length of name and decimal expansion of unit number */
726 	lname = strlen(cd->cd_name);
727 	xunit = number(&num[sizeof(num)], myunit);
728 	lunit = &num[sizeof(num)] - xunit;
729 	if (lname + lunit > sizeof(dev->dv_xname))
730 		panic("config_attach: device name too long");
731 
732 	/* get memory for all device vars */
733 	dev = (struct device *)malloc(ca->ca_devsize, M_DEVBUF,
734 	    cold ? M_NOWAIT : M_WAITOK);
735 	if (!dev)
736 	    panic("config_attach: memory allocation for device softc failed");
737 	memset(dev, 0, ca->ca_devsize);
738 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
739 	dev->dv_class = cd->cd_class;
740 	dev->dv_cfdata = cf;
741 	dev->dv_cfdriver = cd;
742 	dev->dv_cfattach = ca;
743 	dev->dv_unit = myunit;
744 	memcpy(dev->dv_xname, cd->cd_name, lname);
745 	memcpy(dev->dv_xname + lname, xunit, lunit);
746 	dev->dv_parent = parent;
747 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
748 
749 	if (parent == ROOT)
750 		printf("%s (root)", dev->dv_xname);
751 	else {
752 		printf("%s at %s", dev->dv_xname, parent->dv_xname);
753 		if (print)
754 			(void) (*print)(aux, NULL);
755 	}
756 
757 	/* put this device in the devices array */
758 	config_makeroom(dev->dv_unit, cd);
759 	if (cd->cd_devs[dev->dv_unit])
760 		panic("config_attach: duplicate %s", dev->dv_xname);
761 	cd->cd_devs[dev->dv_unit] = dev;
762 
763 	/*
764 	 * Before attaching, clobber any unfound devices that are
765 	 * otherwise identical.
766 	 */
767 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
768 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
769 			if (STREQ(cf->cf_name, cd->cd_name) &&
770 			    cf->cf_unit == dev->dv_unit) {
771 				if (cf->cf_fstate == FSTATE_NOTFOUND)
772 					cf->cf_fstate = FSTATE_FOUND;
773 #ifdef __BROKEN_CONFIG_UNIT_USAGE
774 				/*
775 				 * Bump the unit number on all starred cfdata
776 				 * entries for this device.
777 				 */
778 				if (cf->cf_fstate == FSTATE_STAR)
779 					cf->cf_unit++;
780 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
781 			}
782 		}
783 	}
784 #ifdef __HAVE_DEVICE_REGISTER
785 	device_register(dev, aux);
786 #endif
787 	(*ca->ca_attach)(parent, dev, aux);
788 	config_process_deferred(&deferred_config_queue, dev);
789 	return (dev);
790 }
791 
792 /*
793  * As above, but for pseudo-devices.  Pseudo-devices attached in this
794  * way are silently inserted into the device tree, and their children
795  * attached.
796  *
797  * Note that because pseudo-devices are attached silently, any information
798  * the attach routine wishes to print should be prefixed with the device
799  * name by the attach routine.
800  */
801 struct device *
802 config_attach_pseudo(const char *name, int unit)
803 {
804 	struct device *dev;
805 	struct cfdriver *cd;
806 	struct cfattach *ca;
807 	size_t lname, lunit;
808 	const char *xunit;
809 	int myunit;
810 	char num[10];
811 
812 	cd = config_cfdriver_lookup(name);
813 	if (cd == NULL)
814 		return (NULL);
815 
816 	ca = config_cfattach_lookup_cd(cd, name);
817 	if (ca == NULL)
818 		return (NULL);
819 
820 	if (ca->ca_devsize < sizeof(struct device))
821 		panic("config_attach_pseudo");
822 
823 	if (unit == DVUNIT_ANY) {
824 		for (myunit = 0; myunit < cd->cd_ndevs; myunit++)
825 			if (cd->cd_devs[myunit] == NULL)
826 				break;
827 		/*
828 		 * myunit is now the unit of the first NULL device pointer.
829 		 */
830 	} else {
831 		myunit = unit;
832 		if (myunit < cd->cd_ndevs && cd->cd_devs[myunit] != NULL)
833 			return (NULL);
834 	}
835 
836 	/* compute length of name and decimal expansion of unit number */
837 	lname = strlen(cd->cd_name);
838 	xunit = number(&num[sizeof(num)], myunit);
839 	lunit = &num[sizeof(num)] - xunit;
840 	if (lname + lunit > sizeof(dev->dv_xname))
841 		panic("config_attach_pseudo: device name too long");
842 
843 	/* get memory for all device vars */
844 	dev = (struct device *)malloc(ca->ca_devsize, M_DEVBUF,
845 	    cold ? M_NOWAIT : M_WAITOK);
846 	if (!dev)
847 		panic("config_attach_pseudo: memory allocation for device "
848 		    "softc failed");
849 	memset(dev, 0, ca->ca_devsize);
850 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
851 	dev->dv_class = cd->cd_class;
852 	dev->dv_cfdata = NULL;
853 	dev->dv_cfdriver = cd;
854 	dev->dv_cfattach = ca;
855 	dev->dv_unit = myunit;
856 	memcpy(dev->dv_xname, cd->cd_name, lname);
857 	memcpy(dev->dv_xname + lname, xunit, lunit);
858 	dev->dv_parent = ROOT;
859 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
860 
861 	/* put this device in the devices array */
862 	config_makeroom(dev->dv_unit, cd);
863 	if (cd->cd_devs[dev->dv_unit])
864 		panic("config_attach_pseudo: duplicate %s", dev->dv_xname);
865 	cd->cd_devs[dev->dv_unit] = dev;
866 
867 #if 0	/* XXXJRT not yet */
868 #ifdef __HAVE_DEVICE_REGISTER
869 	device_register(dev, NULL);	/* like a root node */
870 #endif
871 #endif
872 	(*ca->ca_attach)(ROOT, dev, NULL);
873 	config_process_deferred(&deferred_config_queue, dev);
874 	return (dev);
875 }
876 
877 /*
878  * Detach a device.  Optionally forced (e.g. because of hardware
879  * removal) and quiet.  Returns zero if successful, non-zero
880  * (an error code) otherwise.
881  *
882  * Note that this code wants to be run from a process context, so
883  * that the detach can sleep to allow processes which have a device
884  * open to run and unwind their stacks.
885  */
886 int
887 config_detach(struct device *dev, int flags)
888 {
889 	struct cftable *ct;
890 	struct cfdata *cf;
891 	const struct cfattach *ca;
892 	struct cfdriver *cd;
893 #ifdef DIAGNOSTIC
894 	struct device *d;
895 #endif
896 	int rv = 0, i;
897 
898 #ifdef DIAGNOSTIC
899 	if (dev->dv_cfdata != NULL &&
900 	    dev->dv_cfdata->cf_fstate != FSTATE_FOUND &&
901 	    dev->dv_cfdata->cf_fstate != FSTATE_STAR)
902 		panic("config_detach: bad device fstate");
903 #endif
904 	cd = dev->dv_cfdriver;
905 	KASSERT(cd != NULL);
906 
907 	ca = dev->dv_cfattach;
908 	KASSERT(ca != NULL);
909 
910 	/*
911 	 * Ensure the device is deactivated.  If the device doesn't
912 	 * have an activation entry point, we allow DVF_ACTIVE to
913 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
914 	 * device is busy, and the detach fails.
915 	 */
916 	if (ca->ca_activate != NULL)
917 		rv = config_deactivate(dev);
918 
919 	/*
920 	 * Try to detach the device.  If that's not possible, then
921 	 * we either panic() (for the forced but failed case), or
922 	 * return an error.
923 	 */
924 	if (rv == 0) {
925 		if (ca->ca_detach != NULL)
926 			rv = (*ca->ca_detach)(dev, flags);
927 		else
928 			rv = EOPNOTSUPP;
929 	}
930 	if (rv != 0) {
931 		if ((flags & DETACH_FORCE) == 0)
932 			return (rv);
933 		else
934 			panic("config_detach: forced detach of %s failed (%d)",
935 			    dev->dv_xname, rv);
936 	}
937 
938 	/*
939 	 * The device has now been successfully detached.
940 	 */
941 
942 #ifdef DIAGNOSTIC
943 	/*
944 	 * Sanity: If you're successfully detached, you should have no
945 	 * children.  (Note that because children must be attached
946 	 * after parents, we only need to search the latter part of
947 	 * the list.)
948 	 */
949 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
950 	    d = TAILQ_NEXT(d, dv_list)) {
951 		if (d->dv_parent == dev) {
952 			printf("config_detach: detached device %s"
953 			    " has children %s\n", dev->dv_xname, d->dv_xname);
954 			panic("config_detach");
955 		}
956 	}
957 #endif
958 
959 	/*
960 	 * Mark cfdata to show that the unit can be reused, if possible.
961 	 */
962 	TAILQ_FOREACH(ct, &allcftables, ct_list) {
963 		for (cf = ct->ct_cfdata; cf->cf_name; cf++) {
964 			if (STREQ(cf->cf_name, cd->cd_name)) {
965 				if (cf->cf_fstate == FSTATE_FOUND &&
966 				    cf->cf_unit == dev->dv_unit)
967 					cf->cf_fstate = FSTATE_NOTFOUND;
968 #ifdef __BROKEN_CONFIG_UNIT_USAGE
969 				/*
970 				 * Note that we can only re-use a starred
971 				 * unit number if the unit being detached
972 				 * had the last assigned unit number.
973 				 */
974 				if (cf->cf_fstate == FSTATE_STAR &&
975 				    cf->cf_unit == dev->dv_unit + 1)
976 					cf->cf_unit--;
977 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
978 			}
979 		}
980 	}
981 
982 	/*
983 	 * Unlink from device list.
984 	 */
985 	TAILQ_REMOVE(&alldevs, dev, dv_list);
986 
987 	/*
988 	 * Remove from cfdriver's array, tell the world (unless it was
989 	 * a pseudo-device), and free softc.
990 	 */
991 	cd->cd_devs[dev->dv_unit] = NULL;
992 	if (dev->dv_cfdata != NULL && (flags & DETACH_QUIET) == 0)
993 		printf("%s detached\n", dev->dv_xname);
994 	free(dev, M_DEVBUF);
995 
996 	/*
997 	 * If the device now has no units in use, deallocate its softc array.
998 	 */
999 	for (i = 0; i < cd->cd_ndevs; i++)
1000 		if (cd->cd_devs[i] != NULL)
1001 			break;
1002 	if (i == cd->cd_ndevs) {		/* nothing found; deallocate */
1003 		free(cd->cd_devs, M_DEVBUF);
1004 		cd->cd_devs = NULL;
1005 		cd->cd_ndevs = 0;
1006 	}
1007 
1008 	/*
1009 	 * Return success.
1010 	 */
1011 	return (0);
1012 }
1013 
1014 int
1015 config_activate(struct device *dev)
1016 {
1017 	const struct cfattach *ca = dev->dv_cfattach;
1018 	int rv = 0, oflags = dev->dv_flags;
1019 
1020 	if (ca->ca_activate == NULL)
1021 		return (EOPNOTSUPP);
1022 
1023 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
1024 		dev->dv_flags |= DVF_ACTIVE;
1025 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
1026 		if (rv)
1027 			dev->dv_flags = oflags;
1028 	}
1029 	return (rv);
1030 }
1031 
1032 int
1033 config_deactivate(struct device *dev)
1034 {
1035 	const struct cfattach *ca = dev->dv_cfattach;
1036 	int rv = 0, oflags = dev->dv_flags;
1037 
1038 	if (ca->ca_activate == NULL)
1039 		return (EOPNOTSUPP);
1040 
1041 	if (dev->dv_flags & DVF_ACTIVE) {
1042 		dev->dv_flags &= ~DVF_ACTIVE;
1043 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
1044 		if (rv)
1045 			dev->dv_flags = oflags;
1046 	}
1047 	return (rv);
1048 }
1049 
1050 /*
1051  * Defer the configuration of the specified device until all
1052  * of its parent's devices have been attached.
1053  */
1054 void
1055 config_defer(struct device *dev, void (*func)(struct device *))
1056 {
1057 	struct deferred_config *dc;
1058 
1059 	if (dev->dv_parent == NULL)
1060 		panic("config_defer: can't defer config of a root device");
1061 
1062 #ifdef DIAGNOSTIC
1063 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
1064 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1065 		if (dc->dc_dev == dev)
1066 			panic("config_defer: deferred twice");
1067 	}
1068 #endif
1069 
1070 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1071 	if (dc == NULL)
1072 		panic("config_defer: unable to allocate callback");
1073 
1074 	dc->dc_dev = dev;
1075 	dc->dc_func = func;
1076 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
1077 	config_pending_incr();
1078 }
1079 
1080 /*
1081  * Defer some autoconfiguration for a device until after interrupts
1082  * are enabled.
1083  */
1084 void
1085 config_interrupts(struct device *dev, void (*func)(struct device *))
1086 {
1087 	struct deferred_config *dc;
1088 
1089 	/*
1090 	 * If interrupts are enabled, callback now.
1091 	 */
1092 	if (cold == 0) {
1093 		(*func)(dev);
1094 		return;
1095 	}
1096 
1097 #ifdef DIAGNOSTIC
1098 	for (dc = TAILQ_FIRST(&interrupt_config_queue); dc != NULL;
1099 	     dc = TAILQ_NEXT(dc, dc_queue)) {
1100 		if (dc->dc_dev == dev)
1101 			panic("config_interrupts: deferred twice");
1102 	}
1103 #endif
1104 
1105 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
1106 	if (dc == NULL)
1107 		panic("config_interrupts: unable to allocate callback");
1108 
1109 	dc->dc_dev = dev;
1110 	dc->dc_func = func;
1111 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
1112 	config_pending_incr();
1113 }
1114 
1115 /*
1116  * Process a deferred configuration queue.
1117  */
1118 static void
1119 config_process_deferred(struct deferred_config_head *queue,
1120     struct device *parent)
1121 {
1122 	struct deferred_config *dc, *ndc;
1123 
1124 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
1125 		ndc = TAILQ_NEXT(dc, dc_queue);
1126 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
1127 			TAILQ_REMOVE(queue, dc, dc_queue);
1128 			(*dc->dc_func)(dc->dc_dev);
1129 			free(dc, M_DEVBUF);
1130 			config_pending_decr();
1131 		}
1132 	}
1133 }
1134 
1135 /*
1136  * Manipulate the config_pending semaphore.
1137  */
1138 void
1139 config_pending_incr(void)
1140 {
1141 
1142 	config_pending++;
1143 }
1144 
1145 void
1146 config_pending_decr(void)
1147 {
1148 
1149 #ifdef DIAGNOSTIC
1150 	if (config_pending == 0)
1151 		panic("config_pending_decr: config_pending == 0");
1152 #endif
1153 	config_pending--;
1154 	if (config_pending == 0)
1155 		wakeup((void *)&config_pending);
1156 }
1157 
1158 /*
1159  * Register a "finalization" routine.  Finalization routines are
1160  * called iteratively once all real devices have been found during
1161  * autoconfiguration, for as long as any one finalizer has done
1162  * any work.
1163  */
1164 int
1165 config_finalize_register(struct device *dev, int (*fn)(struct device *))
1166 {
1167 	struct finalize_hook *f;
1168 
1169 	/*
1170 	 * If finalization has already been done, invoke the
1171 	 * callback function now.
1172 	 */
1173 	if (config_finalize_done) {
1174 		while ((*fn)(dev) != 0)
1175 			/* loop */ ;
1176 	}
1177 
1178 	/* Ensure this isn't already on the list. */
1179 	TAILQ_FOREACH(f, &config_finalize_list, f_list) {
1180 		if (f->f_func == fn && f->f_dev == dev)
1181 			return (EEXIST);
1182 	}
1183 
1184 	f = malloc(sizeof(*f), M_TEMP, M_WAITOK);
1185 	f->f_func = fn;
1186 	f->f_dev = dev;
1187 	TAILQ_INSERT_TAIL(&config_finalize_list, f, f_list);
1188 
1189 	return (0);
1190 }
1191 
1192 void
1193 config_finalize(void)
1194 {
1195 	struct finalize_hook *f;
1196 	int rv;
1197 
1198 	/* Run the hooks until none of them does any work. */
1199 	do {
1200 		rv = 0;
1201 		TAILQ_FOREACH(f, &config_finalize_list, f_list)
1202 			rv |= (*f->f_func)(f->f_dev);
1203 	} while (rv != 0);
1204 
1205 	config_finalize_done = 1;
1206 
1207 	/* Now free all the hooks. */
1208 	while ((f = TAILQ_FIRST(&config_finalize_list)) != NULL) {
1209 		TAILQ_REMOVE(&config_finalize_list, f, f_list);
1210 		free(f, M_TEMP);
1211 	}
1212 }
1213 
1214 /*
1215  * We need a dummy object to stuff into the evcnt link set to
1216  * ensure that there always is at least one object in the set.
1217  */
1218 static struct evcnt dummy_static_evcnt;
1219 __link_set_add_bss(evcnts, dummy_static_evcnt);
1220 
1221 /*
1222  * Initialize event counters.  This does the attach procedure for
1223  * each of the static event counters in the "evcnts" link set.
1224  */
1225 void
1226 evcnt_init(void)
1227 {
1228 	__link_set_decl(evcnts, struct evcnt);
1229 	struct evcnt * const *evp;
1230 
1231 	__link_set_foreach(evp, evcnts) {
1232 		if (*evp == &dummy_static_evcnt)
1233 			continue;
1234 		evcnt_attach_static(*evp);
1235 	}
1236 }
1237 
1238 /*
1239  * Attach a statically-initialized event.  The type and string pointers
1240  * are already set up.
1241  */
1242 void
1243 evcnt_attach_static(struct evcnt *ev)
1244 {
1245 	int len;
1246 
1247 	len = strlen(ev->ev_group);
1248 #ifdef DIAGNOSTIC
1249 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
1250 		panic("evcnt_attach_static: group length (%s)", ev->ev_group);
1251 #endif
1252 	ev->ev_grouplen = len;
1253 
1254 	len = strlen(ev->ev_name);
1255 #ifdef DIAGNOSTIC
1256 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
1257 		panic("evcnt_attach_static: name length (%s)", ev->ev_name);
1258 #endif
1259 	ev->ev_namelen = len;
1260 
1261 	TAILQ_INSERT_TAIL(&allevents, ev, ev_list);
1262 }
1263 
1264 /*
1265  * Attach a dynamically-initialized event.  Zero it, set up the type
1266  * and string pointers and then act like it was statically initialized.
1267  */
1268 void
1269 evcnt_attach_dynamic(struct evcnt *ev, int type, const struct evcnt *parent,
1270     const char *group, const char *name)
1271 {
1272 
1273 	memset(ev, 0, sizeof *ev);
1274 	ev->ev_type = type;
1275 	ev->ev_parent = parent;
1276 	ev->ev_group = group;
1277 	ev->ev_name = name;
1278 	evcnt_attach_static(ev);
1279 }
1280 
1281 /*
1282  * Detach an event.
1283  */
1284 void
1285 evcnt_detach(struct evcnt *ev)
1286 {
1287 
1288 	TAILQ_REMOVE(&allevents, ev, ev_list);
1289 }
1290 
1291 #ifdef DDB
1292 void
1293 event_print(int full, void (*pr)(const char *, ...))
1294 {
1295 	struct evcnt *evp;
1296 
1297 	TAILQ_FOREACH(evp, &allevents, ev_list) {
1298 		if (evp->ev_count == 0 && !full)
1299 			continue;
1300 
1301 		(*pr)("evcnt type %d: %s %s = %lld\n", evp->ev_type,
1302 		    evp->ev_group, evp->ev_name, evp->ev_count);
1303 	}
1304 }
1305 #endif /* DDB */
1306