xref: /netbsd-src/sys/kern/subr_autoconf.c (revision 0dd5877adce57db949b16ae963e5a6831cccdfb6)
1 /* $NetBSD: subr_autoconf.c,v 1.62 2002/02/15 11:18:26 simonb 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 1.62 2002/02/15 11:18:26 simonb 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 #define	ROOT ((struct device *)NULL)
115 
116 struct matchinfo {
117 	cfmatch_t fn;
118 	struct	device *parent;
119 	void	*aux;
120 	struct	cfdata *match;
121 	int	pri;
122 };
123 
124 static char *number(char *, int);
125 static void mapply(struct matchinfo *, struct cfdata *);
126 
127 struct deferred_config {
128 	TAILQ_ENTRY(deferred_config) dc_queue;
129 	struct device *dc_dev;
130 	void (*dc_func)(struct device *);
131 };
132 
133 TAILQ_HEAD(deferred_config_head, deferred_config);
134 
135 struct deferred_config_head deferred_config_queue;
136 struct deferred_config_head interrupt_config_queue;
137 
138 static void config_process_deferred(struct deferred_config_head *,
139 	struct device *);
140 
141 /* list of all devices */
142 struct devicelist alldevs;
143 
144 /* list of all events */
145 struct evcntlist allevents = TAILQ_HEAD_INITIALIZER(allevents);
146 
147 __volatile int config_pending;		/* semaphore for mountroot */
148 
149 /*
150  * Configure the system's hardware.
151  */
152 void
153 configure(void)
154 {
155 
156 	TAILQ_INIT(&deferred_config_queue);
157 	TAILQ_INIT(&interrupt_config_queue);
158 	TAILQ_INIT(&alldevs);
159 
160 #ifdef USERCONF
161 	if (boothowto & RB_USERCONF)
162 		user_config();
163 #endif
164 
165 	/*
166 	 * Do the machine-dependent portion of autoconfiguration.  This
167 	 * sets the configuration machinery here in motion by "finding"
168 	 * the root bus.  When this function returns, we expect interrupts
169 	 * to be enabled.
170 	 */
171 	cpu_configure();
172 
173 	/*
174 	 * Now that we've found all the hardware, start the real time
175 	 * and statistics clocks.
176 	 */
177 	initclocks();
178 
179 	cold = 0;	/* clocks are running, we're warm now! */
180 
181 	/*
182 	 * Now callback to finish configuration for devices which want
183 	 * to do this once interrupts are enabled.
184 	 */
185 	config_process_deferred(&interrupt_config_queue, NULL);
186 }
187 
188 /*
189  * Apply the matching function and choose the best.  This is used
190  * a few times and we want to keep the code small.
191  */
192 static void
193 mapply(struct matchinfo *m, struct cfdata *cf)
194 {
195 	int pri;
196 
197 	if (m->fn != NULL)
198 		pri = (*m->fn)(m->parent, cf, m->aux);
199 	else {
200 	        if (cf->cf_attach->ca_match == NULL) {
201 			panic("mapply: no match function for '%s' device\n",
202 			    cf->cf_driver->cd_name);
203 		}
204 		pri = (*cf->cf_attach->ca_match)(m->parent, cf, m->aux);
205 	}
206 	if (pri > m->pri) {
207 		m->match = cf;
208 		m->pri = pri;
209 	}
210 }
211 
212 /*
213  * Iterate over all potential children of some device, calling the given
214  * function (default being the child's match function) for each one.
215  * Nonzero returns are matches; the highest value returned is considered
216  * the best match.  Return the `found child' if we got a match, or NULL
217  * otherwise.  The `aux' pointer is simply passed on through.
218  *
219  * Note that this function is designed so that it can be used to apply
220  * an arbitrary function to all potential children (its return value
221  * can be ignored).
222  */
223 struct cfdata *
224 config_search(cfmatch_t fn, struct device *parent, void *aux)
225 {
226 	struct cfdata *cf;
227 	short *p;
228 	struct matchinfo m;
229 
230 	m.fn = fn;
231 	m.parent = parent;
232 	m.aux = aux;
233 	m.match = NULL;
234 	m.pri = 0;
235 	for (cf = cfdata; cf->cf_driver; cf++) {
236 		/*
237 		 * Skip cf if no longer eligible, otherwise scan through
238 		 * parents for one matching `parent', and try match function.
239 		 */
240 		if (cf->cf_fstate == FSTATE_FOUND)
241 			continue;
242 		for (p = cf->cf_parents; *p >= 0; p++)
243 			if (parent->dv_cfdata == &cfdata[*p])
244 				mapply(&m, cf);
245 	}
246 	return (m.match);
247 }
248 
249 /*
250  * Find the given root device.
251  * This is much like config_search, but there is no parent.
252  */
253 struct cfdata *
254 config_rootsearch(cfmatch_t fn, const char *rootname, void *aux)
255 {
256 	struct cfdata *cf;
257 	short *p;
258 	struct matchinfo m;
259 
260 	m.fn = fn;
261 	m.parent = ROOT;
262 	m.aux = aux;
263 	m.match = NULL;
264 	m.pri = 0;
265 	/*
266 	 * Look at root entries for matching name.  We do not bother
267 	 * with found-state here since only one root should ever be
268 	 * searched (and it must be done first).
269 	 */
270 	for (p = cfroots; *p >= 0; p++) {
271 		cf = &cfdata[*p];
272 		if (strcmp(cf->cf_driver->cd_name, rootname) == 0)
273 			mapply(&m, cf);
274 	}
275 	return (m.match);
276 }
277 
278 static const char *msgs[3] = { "", " not configured\n", " unsupported\n" };
279 
280 /*
281  * The given `aux' argument describes a device that has been found
282  * on the given parent, but not necessarily configured.  Locate the
283  * configuration data for that device (using the submatch function
284  * provided, or using candidates' cd_match configuration driver
285  * functions) and attach it, and return true.  If the device was
286  * not configured, call the given `print' function and return 0.
287  */
288 struct device *
289 config_found_sm(struct device *parent, void *aux, cfprint_t print,
290     cfmatch_t submatch)
291 {
292 	struct cfdata *cf;
293 
294 	if ((cf = config_search(submatch, parent, aux)) != NULL)
295 		return (config_attach(parent, cf, aux, print));
296 	if (print)
297 		printf("%s", msgs[(*print)(aux, parent->dv_xname)]);
298 	return (NULL);
299 }
300 
301 /*
302  * As above, but for root devices.
303  */
304 struct device *
305 config_rootfound(const char *rootname, void *aux)
306 {
307 	struct cfdata *cf;
308 
309 	if ((cf = config_rootsearch((cfmatch_t)NULL, rootname, aux)) != NULL)
310 		return (config_attach(ROOT, cf, aux, (cfprint_t)NULL));
311 	printf("root device %s not configured\n", rootname);
312 	return (NULL);
313 }
314 
315 /* just like sprintf(buf, "%d") except that it works from the end */
316 static char *
317 number(char *ep, int n)
318 {
319 
320 	*--ep = 0;
321 	while (n >= 10) {
322 		*--ep = (n % 10) + '0';
323 		n /= 10;
324 	}
325 	*--ep = n + '0';
326 	return (ep);
327 }
328 
329 /*
330  * Expand the size of the cd_devs array if necessary.
331  */
332 void
333 config_makeroom(int n, struct cfdriver *cd)
334 {
335 	int old, new;
336 	void **nsp;
337 
338 	if (n < cd->cd_ndevs)
339 		return;
340 
341 	/*
342 	 * Need to expand the array.
343 	 */
344 	old = cd->cd_ndevs;
345 	if (old == 0)
346 		new = MINALLOCSIZE / sizeof(void *);
347 	else
348 		new = old * 2;
349 	while (new <= n)
350 		new *= 2;
351 	cd->cd_ndevs = new;
352 	nsp = malloc(new * sizeof(void *), M_DEVBUF,
353 	    cold ? M_NOWAIT : M_WAITOK);
354 	if (nsp == NULL)
355 		panic("config_attach: %sing dev array",
356 		    old != 0 ? "expand" : "creat");
357 	memset(nsp + old, 0, (new - old) * sizeof(void *));
358 	if (old != 0) {
359 		memcpy(nsp, cd->cd_devs, old * sizeof(void *));
360 		free(cd->cd_devs, M_DEVBUF);
361 	}
362 	cd->cd_devs = nsp;
363 }
364 
365 /*
366  * Attach a found device.  Allocates memory for device variables.
367  */
368 struct device *
369 config_attach(struct device *parent, struct cfdata *cf, void *aux,
370 	cfprint_t print)
371 {
372 	struct device *dev;
373 	struct cfdriver *cd;
374 	struct cfattach *ca;
375 	size_t lname, lunit;
376 	const char *xunit;
377 	int myunit;
378 	char num[10];
379 
380 	cd = cf->cf_driver;
381 	ca = cf->cf_attach;
382 	if (ca->ca_devsize < sizeof(struct device))
383 		panic("config_attach");
384 #ifndef __BROKEN_CONFIG_UNIT_USAGE
385 	if (cf->cf_fstate == FSTATE_STAR) {
386 		for (myunit = cf->cf_unit; myunit < cd->cd_ndevs; myunit++)
387 			if (cd->cd_devs[myunit] == NULL)
388 				break;
389 		/*
390 		 * myunit is now the unit of the first NULL device pointer,
391 		 * or max(cd->cd_ndevs,cf->cf_unit).
392 		 */
393 	} else {
394 		myunit = cf->cf_unit;
395 #else /* __BROKEN_CONFIG_UNIT_USAGE */
396 	myunit = cf->cf_unit;
397 	if (cf->cf_fstate == FSTATE_STAR)
398 		cf->cf_unit++;
399 	else {
400 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
401 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
402 		cf->cf_fstate = FSTATE_FOUND;
403 	}
404 
405 	/* compute length of name and decimal expansion of unit number */
406 	lname = strlen(cd->cd_name);
407 	xunit = number(&num[sizeof(num)], myunit);
408 	lunit = &num[sizeof(num)] - xunit;
409 	if (lname + lunit >= sizeof(dev->dv_xname))
410 		panic("config_attach: device name too long");
411 
412 	/* get memory for all device vars */
413 	dev = (struct device *)malloc(ca->ca_devsize, M_DEVBUF,
414 	    cold ? M_NOWAIT : M_WAITOK);
415 	if (!dev)
416 	    panic("config_attach: memory allocation for device softc failed");
417 	memset(dev, 0, ca->ca_devsize);
418 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
419 	dev->dv_class = cd->cd_class;
420 	dev->dv_cfdata = cf;
421 	dev->dv_unit = myunit;
422 	memcpy(dev->dv_xname, cd->cd_name, lname);
423 	memcpy(dev->dv_xname + lname, xunit, lunit);
424 	dev->dv_parent = parent;
425 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
426 
427 	if (parent == ROOT)
428 		printf("%s (root)", dev->dv_xname);
429 	else {
430 		printf("%s at %s", dev->dv_xname, parent->dv_xname);
431 		if (print)
432 			(void) (*print)(aux, NULL);
433 	}
434 
435 	/* put this device in the devices array */
436 	config_makeroom(dev->dv_unit, cd);
437 	if (cd->cd_devs[dev->dv_unit])
438 		panic("config_attach: duplicate %s", dev->dv_xname);
439 	cd->cd_devs[dev->dv_unit] = dev;
440 
441 	/*
442 	 * Before attaching, clobber any unfound devices that are
443 	 * otherwise identical.
444 	 */
445 #ifdef __BROKEN_CONFIG_UNIT_USAGE
446 	/* bump the unit number on all starred cfdata for this device. */
447 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
448 	for (cf = cfdata; cf->cf_driver; cf++)
449 		if (cf->cf_driver == cd && cf->cf_unit == dev->dv_unit) {
450 			if (cf->cf_fstate == FSTATE_NOTFOUND)
451 				cf->cf_fstate = FSTATE_FOUND;
452 #ifdef __BROKEN_CONFIG_UNIT_USAGE
453 			if (cf->cf_fstate == FSTATE_STAR)
454 				cf->cf_unit++;
455 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
456 		}
457 #ifdef __HAVE_DEVICE_REGISTER
458 	device_register(dev, aux);
459 #endif
460 	(*ca->ca_attach)(parent, dev, aux);
461 	config_process_deferred(&deferred_config_queue, dev);
462 	return (dev);
463 }
464 
465 /*
466  * Detach a device.  Optionally forced (e.g. because of hardware
467  * removal) and quiet.  Returns zero if successful, non-zero
468  * (an error code) otherwise.
469  *
470  * Note that this code wants to be run from a process context, so
471  * that the detach can sleep to allow processes which have a device
472  * open to run and unwind their stacks.
473  */
474 int
475 config_detach(struct device *dev, int flags)
476 {
477 	struct cfdata *cf;
478 	struct cfattach *ca;
479 	struct cfdriver *cd;
480 #ifdef DIAGNOSTIC
481 	struct device *d;
482 #endif
483 	int rv = 0, i;
484 
485 	cf = dev->dv_cfdata;
486 #ifdef DIAGNOSTIC
487 	if (cf->cf_fstate != FSTATE_FOUND && cf->cf_fstate != FSTATE_STAR)
488 		panic("config_detach: bad device fstate");
489 #endif
490 	ca = cf->cf_attach;
491 	cd = cf->cf_driver;
492 
493 	/*
494 	 * Ensure the device is deactivated.  If the device doesn't
495 	 * have an activation entry point, we allow DVF_ACTIVE to
496 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
497 	 * device is busy, and the detach fails.
498 	 */
499 	if (ca->ca_activate != NULL)
500 		rv = config_deactivate(dev);
501 
502 	/*
503 	 * Try to detach the device.  If that's not possible, then
504 	 * we either panic() (for the forced but failed case), or
505 	 * return an error.
506 	 */
507 	if (rv == 0) {
508 		if (ca->ca_detach != NULL)
509 			rv = (*ca->ca_detach)(dev, flags);
510 		else
511 			rv = EOPNOTSUPP;
512 	}
513 	if (rv != 0) {
514 		if ((flags & DETACH_FORCE) == 0)
515 			return (rv);
516 		else
517 			panic("config_detach: forced detach of %s failed (%d)",
518 			    dev->dv_xname, rv);
519 	}
520 
521 	/*
522 	 * The device has now been successfully detached.
523 	 */
524 
525 #ifdef DIAGNOSTIC
526 	/*
527 	 * Sanity: If you're successfully detached, you should have no
528 	 * children.  (Note that because children must be attached
529 	 * after parents, we only need to search the latter part of
530 	 * the list.)
531 	 */
532 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
533 	    d = TAILQ_NEXT(d, dv_list)) {
534 		if (d->dv_parent == dev) {
535 			printf("config_detach: detached device %s"
536 			    " has children %s\n", dev->dv_xname, d->dv_xname);
537 			panic("config_detach");
538 		}
539 	}
540 #endif
541 
542 	/*
543 	 * Mark cfdata to show that the unit can be reused, if possible.
544 	 */
545 #ifdef __BROKEN_CONFIG_UNIT_USAGE
546 	/*
547 	 * Note that we can only re-use a starred unit number if the unit
548 	 * being detached had the last assigned unit number.
549 	 */
550 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
551 	for (cf = cfdata; cf->cf_driver; cf++) {
552 		if (cf->cf_driver == cd) {
553 			if (cf->cf_fstate == FSTATE_FOUND &&
554 			    cf->cf_unit == dev->dv_unit)
555 				cf->cf_fstate = FSTATE_NOTFOUND;
556 #ifdef __BROKEN_CONFIG_UNIT_USAGE
557 			if (cf->cf_fstate == FSTATE_STAR &&
558 			    cf->cf_unit == dev->dv_unit + 1)
559 				cf->cf_unit--;
560 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
561 		}
562 	}
563 
564 	/*
565 	 * Unlink from device list.
566 	 */
567 	TAILQ_REMOVE(&alldevs, dev, dv_list);
568 
569 	/*
570 	 * Remove from cfdriver's array, tell the world, and free softc.
571 	 */
572 	cd->cd_devs[dev->dv_unit] = NULL;
573 	if ((flags & DETACH_QUIET) == 0)
574 		printf("%s detached\n", dev->dv_xname);
575 	free(dev, M_DEVBUF);
576 
577 	/*
578 	 * If the device now has no units in use, deallocate its softc array.
579 	 */
580 	for (i = 0; i < cd->cd_ndevs; i++)
581 		if (cd->cd_devs[i] != NULL)
582 			break;
583 	if (i == cd->cd_ndevs) {		/* nothing found; deallocate */
584 		free(cd->cd_devs, M_DEVBUF);
585 		cd->cd_devs = NULL;
586 		cd->cd_ndevs = 0;
587 	}
588 
589 	/*
590 	 * Return success.
591 	 */
592 	return (0);
593 }
594 
595 int
596 config_activate(struct device *dev)
597 {
598 	struct cfattach *ca = dev->dv_cfdata->cf_attach;
599 	int rv = 0, oflags = dev->dv_flags;
600 
601 	if (ca->ca_activate == NULL)
602 		return (EOPNOTSUPP);
603 
604 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
605 		dev->dv_flags |= DVF_ACTIVE;
606 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
607 		if (rv)
608 			dev->dv_flags = oflags;
609 	}
610 	return (rv);
611 }
612 
613 int
614 config_deactivate(struct device *dev)
615 {
616 	struct cfattach *ca = dev->dv_cfdata->cf_attach;
617 	int rv = 0, oflags = dev->dv_flags;
618 
619 	if (ca->ca_activate == NULL)
620 		return (EOPNOTSUPP);
621 
622 	if (dev->dv_flags & DVF_ACTIVE) {
623 		dev->dv_flags &= ~DVF_ACTIVE;
624 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
625 		if (rv)
626 			dev->dv_flags = oflags;
627 	}
628 	return (rv);
629 }
630 
631 /*
632  * Defer the configuration of the specified device until all
633  * of its parent's devices have been attached.
634  */
635 void
636 config_defer(struct device *dev, void (*func)(struct device *))
637 {
638 	struct deferred_config *dc;
639 
640 	if (dev->dv_parent == NULL)
641 		panic("config_defer: can't defer config of a root device");
642 
643 #ifdef DIAGNOSTIC
644 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
645 	     dc = TAILQ_NEXT(dc, dc_queue)) {
646 		if (dc->dc_dev == dev)
647 			panic("config_defer: deferred twice");
648 	}
649 #endif
650 
651 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
652 	if (dc == NULL)
653 		panic("config_defer: unable to allocate callback");
654 
655 	dc->dc_dev = dev;
656 	dc->dc_func = func;
657 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
658 	config_pending_incr();
659 }
660 
661 /*
662  * Defer some autoconfiguration for a device until after interrupts
663  * are enabled.
664  */
665 void
666 config_interrupts(struct device *dev, void (*func)(struct device *))
667 {
668 	struct deferred_config *dc;
669 
670 	/*
671 	 * If interrupts are enabled, callback now.
672 	 */
673 	if (cold == 0) {
674 		(*func)(dev);
675 		return;
676 	}
677 
678 #ifdef DIAGNOSTIC
679 	for (dc = TAILQ_FIRST(&interrupt_config_queue); dc != NULL;
680 	     dc = TAILQ_NEXT(dc, dc_queue)) {
681 		if (dc->dc_dev == dev)
682 			panic("config_interrupts: deferred twice");
683 	}
684 #endif
685 
686 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
687 	if (dc == NULL)
688 		panic("config_interrupts: unable to allocate callback");
689 
690 	dc->dc_dev = dev;
691 	dc->dc_func = func;
692 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
693 	config_pending_incr();
694 }
695 
696 /*
697  * Process a deferred configuration queue.
698  */
699 static void
700 config_process_deferred(struct deferred_config_head *queue,
701     struct device *parent)
702 {
703 	struct deferred_config *dc, *ndc;
704 
705 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
706 		ndc = TAILQ_NEXT(dc, dc_queue);
707 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
708 			TAILQ_REMOVE(queue, dc, dc_queue);
709 			(*dc->dc_func)(dc->dc_dev);
710 			free(dc, M_DEVBUF);
711 			config_pending_decr();
712 		}
713 	}
714 }
715 
716 /*
717  * Manipulate the config_pending semaphore.
718  */
719 void
720 config_pending_incr(void)
721 {
722 
723 	config_pending++;
724 }
725 
726 void
727 config_pending_decr(void)
728 {
729 
730 #ifdef DIAGNOSTIC
731 	if (config_pending == 0)
732 		panic("config_pending_decr: config_pending == 0");
733 #endif
734 	config_pending--;
735 	if (config_pending == 0)
736 		wakeup((void *)&config_pending);
737 }
738 
739 /*
740  * Attach a statically-initialized event.  The type and string pointers
741  * are already set up.
742  */
743 void
744 evcnt_attach_static(struct evcnt *ev)
745 {
746 	int len;
747 
748 	len = strlen(ev->ev_group);
749 #ifdef DIAGNOSTIC
750 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
751 		panic("evcnt_attach_static: group length (%s)", ev->ev_group);
752 #endif
753 	ev->ev_grouplen = len;
754 
755 	len = strlen(ev->ev_name);
756 #ifdef DIAGNOSTIC
757 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
758 		panic("evcnt_attach_static: name length (%s)", ev->ev_name);
759 #endif
760 	ev->ev_namelen = len;
761 
762 	TAILQ_INSERT_TAIL(&allevents, ev, ev_list);
763 }
764 
765 /*
766  * Attach a dynamically-initialized event.  Zero it, set up the type
767  * and string pointers and then act like it was statically initialized.
768  */
769 void
770 evcnt_attach_dynamic(struct evcnt *ev, int type, const struct evcnt *parent,
771     const char *group, const char *name)
772 {
773 
774 	memset(ev, 0, sizeof *ev);
775 	ev->ev_type = type;
776 	ev->ev_parent = parent;
777 	ev->ev_group = group;
778 	ev->ev_name = name;
779 	evcnt_attach_static(ev);
780 }
781 
782 /*
783  * Detach an event.
784  */
785 void
786 evcnt_detach(struct evcnt *ev)
787 {
788 
789 	TAILQ_REMOVE(&allevents, ev, ev_list);
790 }
791 
792 #ifdef DDB
793 void
794 event_print(int full, void (*pr)(const char *, ...))
795 {
796 	struct evcnt *evp;
797 
798 	TAILQ_FOREACH(evp, &allevents, ev_list) {
799 		if (evp->ev_count == 0 && !full)
800 			continue;
801 
802 		(*pr)("evcnt type %d: %s %s = %lld\n", evp->ev_type,
803 		    evp->ev_group, evp->ev_name, evp->ev_count);
804 	}
805 }
806 #endif /* DDB */
807