xref: /netbsd-src/sys/kern/subr_autoconf.c (revision 1ca5c1b28139779176bd5c13ad7c5f25c0bcd5f8)
1 /* $NetBSD: subr_autoconf.c,v 1.61 2001/12/10 00:33:04 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 1.61 2001/12/10 00:33:04 thorpej Exp $");
85 
86 #include <sys/param.h>
87 #include <sys/device.h>
88 #include <sys/malloc.h>
89 #include <sys/systm.h>
90 #include <sys/kernel.h>
91 #include <sys/errno.h>
92 #include <sys/proc.h>
93 #include <machine/limits.h>
94 
95 #include "opt_userconf.h"
96 #ifdef USERCONF
97 #include <sys/userconf.h>
98 #include <sys/reboot.h>
99 #endif
100 
101 /*
102  * Autoconfiguration subroutines.
103  */
104 
105 /*
106  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
107  * devices and drivers are found via these tables.
108  */
109 extern struct cfdata cfdata[];
110 extern short cfroots[];
111 
112 #define	ROOT ((struct device *)NULL)
113 
114 struct matchinfo {
115 	cfmatch_t fn;
116 	struct	device *parent;
117 	void	*aux;
118 	struct	cfdata *match;
119 	int	pri;
120 };
121 
122 static char *number(char *, int);
123 static void mapply(struct matchinfo *, struct cfdata *);
124 
125 struct deferred_config {
126 	TAILQ_ENTRY(deferred_config) dc_queue;
127 	struct device *dc_dev;
128 	void (*dc_func)(struct device *);
129 };
130 
131 TAILQ_HEAD(deferred_config_head, deferred_config);
132 
133 struct deferred_config_head deferred_config_queue;
134 struct deferred_config_head interrupt_config_queue;
135 
136 static void config_process_deferred(struct deferred_config_head *,
137 	struct device *);
138 
139 /* list of all devices */
140 struct devicelist alldevs;
141 
142 /* list of all events */
143 struct evcntlist allevents = TAILQ_HEAD_INITIALIZER(allevents);
144 
145 __volatile int config_pending;		/* semaphore for mountroot */
146 
147 /*
148  * Configure the system's hardware.
149  */
150 void
151 configure(void)
152 {
153 
154 	TAILQ_INIT(&deferred_config_queue);
155 	TAILQ_INIT(&interrupt_config_queue);
156 	TAILQ_INIT(&alldevs);
157 
158 #ifdef USERCONF
159 	if (boothowto & RB_USERCONF)
160 		user_config();
161 #endif
162 
163 	/*
164 	 * Do the machine-dependent portion of autoconfiguration.  This
165 	 * sets the configuration machinery here in motion by "finding"
166 	 * the root bus.  When this function returns, we expect interrupts
167 	 * to be enabled.
168 	 */
169 	cpu_configure();
170 
171 	/*
172 	 * Now that we've found all the hardware, start the real time
173 	 * and statistics clocks.
174 	 */
175 	initclocks();
176 
177 	cold = 0;	/* clocks are running, we're warm now! */
178 
179 	/*
180 	 * Now callback to finish configuration for devices which want
181 	 * to do this once interrupts are enabled.
182 	 */
183 	config_process_deferred(&interrupt_config_queue, NULL);
184 }
185 
186 /*
187  * Apply the matching function and choose the best.  This is used
188  * a few times and we want to keep the code small.
189  */
190 static void
191 mapply(struct matchinfo *m, struct cfdata *cf)
192 {
193 	int pri;
194 
195 	if (m->fn != NULL)
196 		pri = (*m->fn)(m->parent, cf, m->aux);
197 	else {
198 	        if (cf->cf_attach->ca_match == NULL) {
199 			panic("mapply: no match function for '%s' device\n",
200 			    cf->cf_driver->cd_name);
201 		}
202 		pri = (*cf->cf_attach->ca_match)(m->parent, cf, m->aux);
203 	}
204 	if (pri > m->pri) {
205 		m->match = cf;
206 		m->pri = pri;
207 	}
208 }
209 
210 /*
211  * Iterate over all potential children of some device, calling the given
212  * function (default being the child's match function) for each one.
213  * Nonzero returns are matches; the highest value returned is considered
214  * the best match.  Return the `found child' if we got a match, or NULL
215  * otherwise.  The `aux' pointer is simply passed on through.
216  *
217  * Note that this function is designed so that it can be used to apply
218  * an arbitrary function to all potential children (its return value
219  * can be ignored).
220  */
221 struct cfdata *
222 config_search(cfmatch_t fn, struct device *parent, void *aux)
223 {
224 	struct cfdata *cf;
225 	short *p;
226 	struct matchinfo m;
227 
228 	m.fn = fn;
229 	m.parent = parent;
230 	m.aux = aux;
231 	m.match = NULL;
232 	m.pri = 0;
233 	for (cf = cfdata; cf->cf_driver; cf++) {
234 		/*
235 		 * Skip cf if no longer eligible, otherwise scan through
236 		 * parents for one matching `parent', and try match function.
237 		 */
238 		if (cf->cf_fstate == FSTATE_FOUND)
239 			continue;
240 		for (p = cf->cf_parents; *p >= 0; p++)
241 			if (parent->dv_cfdata == &cfdata[*p])
242 				mapply(&m, cf);
243 	}
244 	return (m.match);
245 }
246 
247 /*
248  * Find the given root device.
249  * This is much like config_search, but there is no parent.
250  */
251 struct cfdata *
252 config_rootsearch(cfmatch_t fn, const char *rootname, void *aux)
253 {
254 	struct cfdata *cf;
255 	short *p;
256 	struct matchinfo m;
257 
258 	m.fn = fn;
259 	m.parent = ROOT;
260 	m.aux = aux;
261 	m.match = NULL;
262 	m.pri = 0;
263 	/*
264 	 * Look at root entries for matching name.  We do not bother
265 	 * with found-state here since only one root should ever be
266 	 * searched (and it must be done first).
267 	 */
268 	for (p = cfroots; *p >= 0; p++) {
269 		cf = &cfdata[*p];
270 		if (strcmp(cf->cf_driver->cd_name, rootname) == 0)
271 			mapply(&m, cf);
272 	}
273 	return (m.match);
274 }
275 
276 static const char *msgs[3] = { "", " not configured\n", " unsupported\n" };
277 
278 /*
279  * The given `aux' argument describes a device that has been found
280  * on the given parent, but not necessarily configured.  Locate the
281  * configuration data for that device (using the submatch function
282  * provided, or using candidates' cd_match configuration driver
283  * functions) and attach it, and return true.  If the device was
284  * not configured, call the given `print' function and return 0.
285  */
286 struct device *
287 config_found_sm(struct device *parent, void *aux, cfprint_t print,
288     cfmatch_t submatch)
289 {
290 	struct cfdata *cf;
291 
292 	if ((cf = config_search(submatch, parent, aux)) != NULL)
293 		return (config_attach(parent, cf, aux, print));
294 	if (print)
295 		printf("%s", msgs[(*print)(aux, parent->dv_xname)]);
296 	return (NULL);
297 }
298 
299 /*
300  * As above, but for root devices.
301  */
302 struct device *
303 config_rootfound(const char *rootname, void *aux)
304 {
305 	struct cfdata *cf;
306 
307 	if ((cf = config_rootsearch((cfmatch_t)NULL, rootname, aux)) != NULL)
308 		return (config_attach(ROOT, cf, aux, (cfprint_t)NULL));
309 	printf("root device %s not configured\n", rootname);
310 	return (NULL);
311 }
312 
313 /* just like sprintf(buf, "%d") except that it works from the end */
314 static char *
315 number(char *ep, int n)
316 {
317 
318 	*--ep = 0;
319 	while (n >= 10) {
320 		*--ep = (n % 10) + '0';
321 		n /= 10;
322 	}
323 	*--ep = n + '0';
324 	return (ep);
325 }
326 
327 /*
328  * Expand the size of the cd_devs array if necessary.
329  */
330 void
331 config_makeroom(int n, struct cfdriver *cd)
332 {
333 	int old, new;
334 	void **nsp;
335 
336 	if (n < cd->cd_ndevs)
337 		return;
338 
339 	/*
340 	 * Need to expand the array.
341 	 */
342 	old = cd->cd_ndevs;
343 	if (old == 0)
344 		new = MINALLOCSIZE / sizeof(void *);
345 	else
346 		new = old * 2;
347 	while (new <= n)
348 		new *= 2;
349 	cd->cd_ndevs = new;
350 	nsp = malloc(new * sizeof(void *), M_DEVBUF,
351 	    cold ? M_NOWAIT : M_WAITOK);
352 	if (nsp == NULL)
353 		panic("config_attach: %sing dev array",
354 		    old != 0 ? "expand" : "creat");
355 	memset(nsp + old, 0, (new - old) * sizeof(void *));
356 	if (old != 0) {
357 		memcpy(nsp, cd->cd_devs, old * sizeof(void *));
358 		free(cd->cd_devs, M_DEVBUF);
359 	}
360 	cd->cd_devs = nsp;
361 }
362 
363 /*
364  * Attach a found device.  Allocates memory for device variables.
365  */
366 struct device *
367 config_attach(struct device *parent, struct cfdata *cf, void *aux,
368 	cfprint_t print)
369 {
370 	struct device *dev;
371 	struct cfdriver *cd;
372 	struct cfattach *ca;
373 	size_t lname, lunit;
374 	const char *xunit;
375 	int myunit;
376 	char num[10];
377 
378 	cd = cf->cf_driver;
379 	ca = cf->cf_attach;
380 	if (ca->ca_devsize < sizeof(struct device))
381 		panic("config_attach");
382 #ifndef __BROKEN_CONFIG_UNIT_USAGE
383 	if (cf->cf_fstate == FSTATE_STAR) {
384 		for (myunit = cf->cf_unit; myunit < cd->cd_ndevs; myunit++)
385 			if (cd->cd_devs[myunit] == NULL)
386 				break;
387 		/*
388 		 * myunit is now the unit of the first NULL device pointer,
389 		 * or max(cd->cd_ndevs,cf->cf_unit).
390 		 */
391 	} else {
392 		myunit = cf->cf_unit;
393 #else /* __BROKEN_CONFIG_UNIT_USAGE */
394 	myunit = cf->cf_unit;
395 	if (cf->cf_fstate == FSTATE_STAR)
396 		cf->cf_unit++;
397 	else {
398 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
399 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
400 		cf->cf_fstate = FSTATE_FOUND;
401 	}
402 
403 	/* compute length of name and decimal expansion of unit number */
404 	lname = strlen(cd->cd_name);
405 	xunit = number(&num[sizeof(num)], myunit);
406 	lunit = &num[sizeof(num)] - xunit;
407 	if (lname + lunit >= sizeof(dev->dv_xname))
408 		panic("config_attach: device name too long");
409 
410 	/* get memory for all device vars */
411 	dev = (struct device *)malloc(ca->ca_devsize, M_DEVBUF,
412 	    cold ? M_NOWAIT : M_WAITOK);
413 	if (!dev)
414 	    panic("config_attach: memory allocation for device softc failed");
415 	memset(dev, 0, ca->ca_devsize);
416 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
417 	dev->dv_class = cd->cd_class;
418 	dev->dv_cfdata = cf;
419 	dev->dv_unit = myunit;
420 	memcpy(dev->dv_xname, cd->cd_name, lname);
421 	memcpy(dev->dv_xname + lname, xunit, lunit);
422 	dev->dv_parent = parent;
423 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
424 
425 	if (parent == ROOT)
426 		printf("%s (root)", dev->dv_xname);
427 	else {
428 		printf("%s at %s", dev->dv_xname, parent->dv_xname);
429 		if (print)
430 			(void) (*print)(aux, NULL);
431 	}
432 
433 	/* put this device in the devices array */
434 	config_makeroom(dev->dv_unit, cd);
435 	if (cd->cd_devs[dev->dv_unit])
436 		panic("config_attach: duplicate %s", dev->dv_xname);
437 	cd->cd_devs[dev->dv_unit] = dev;
438 
439 	/*
440 	 * Before attaching, clobber any unfound devices that are
441 	 * otherwise identical.
442 	 */
443 #ifdef __BROKEN_CONFIG_UNIT_USAGE
444 	/* bump the unit number on all starred cfdata for this device. */
445 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
446 	for (cf = cfdata; cf->cf_driver; cf++)
447 		if (cf->cf_driver == cd && cf->cf_unit == dev->dv_unit) {
448 			if (cf->cf_fstate == FSTATE_NOTFOUND)
449 				cf->cf_fstate = FSTATE_FOUND;
450 #ifdef __BROKEN_CONFIG_UNIT_USAGE
451 			if (cf->cf_fstate == FSTATE_STAR)
452 				cf->cf_unit++;
453 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
454 		}
455 #ifdef __HAVE_DEVICE_REGISTER
456 	device_register(dev, aux);
457 #endif
458 	(*ca->ca_attach)(parent, dev, aux);
459 	config_process_deferred(&deferred_config_queue, dev);
460 	return (dev);
461 }
462 
463 /*
464  * Detach a device.  Optionally forced (e.g. because of hardware
465  * removal) and quiet.  Returns zero if successful, non-zero
466  * (an error code) otherwise.
467  *
468  * Note that this code wants to be run from a process context, so
469  * that the detach can sleep to allow processes which have a device
470  * open to run and unwind their stacks.
471  */
472 int
473 config_detach(struct device *dev, int flags)
474 {
475 	struct cfdata *cf;
476 	struct cfattach *ca;
477 	struct cfdriver *cd;
478 #ifdef DIAGNOSTIC
479 	struct device *d;
480 #endif
481 	int rv = 0, i;
482 
483 	cf = dev->dv_cfdata;
484 #ifdef DIAGNOSTIC
485 	if (cf->cf_fstate != FSTATE_FOUND && cf->cf_fstate != FSTATE_STAR)
486 		panic("config_detach: bad device fstate");
487 #endif
488 	ca = cf->cf_attach;
489 	cd = cf->cf_driver;
490 
491 	/*
492 	 * Ensure the device is deactivated.  If the device doesn't
493 	 * have an activation entry point, we allow DVF_ACTIVE to
494 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
495 	 * device is busy, and the detach fails.
496 	 */
497 	if (ca->ca_activate != NULL)
498 		rv = config_deactivate(dev);
499 
500 	/*
501 	 * Try to detach the device.  If that's not possible, then
502 	 * we either panic() (for the forced but failed case), or
503 	 * return an error.
504 	 */
505 	if (rv == 0) {
506 		if (ca->ca_detach != NULL)
507 			rv = (*ca->ca_detach)(dev, flags);
508 		else
509 			rv = EOPNOTSUPP;
510 	}
511 	if (rv != 0) {
512 		if ((flags & DETACH_FORCE) == 0)
513 			return (rv);
514 		else
515 			panic("config_detach: forced detach of %s failed (%d)",
516 			    dev->dv_xname, rv);
517 	}
518 
519 	/*
520 	 * The device has now been successfully detached.
521 	 */
522 
523 #ifdef DIAGNOSTIC
524 	/*
525 	 * Sanity: If you're successfully detached, you should have no
526 	 * children.  (Note that because children must be attached
527 	 * after parents, we only need to search the latter part of
528 	 * the list.)
529 	 */
530 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
531 	    d = TAILQ_NEXT(d, dv_list)) {
532 		if (d->dv_parent == dev) {
533 			printf("config_detach: detached device %s"
534 			    " has children %s\n", dev->dv_xname, d->dv_xname);
535 			panic("config_detach");
536 		}
537 	}
538 #endif
539 
540 	/*
541 	 * Mark cfdata to show that the unit can be reused, if possible.
542 	 */
543 #ifdef __BROKEN_CONFIG_UNIT_USAGE
544 	/*
545 	 * Note that we can only re-use a starred unit number if the unit
546 	 * being detached had the last assigned unit number.
547 	 */
548 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
549 	for (cf = cfdata; cf->cf_driver; cf++) {
550 		if (cf->cf_driver == cd) {
551 			if (cf->cf_fstate == FSTATE_FOUND &&
552 			    cf->cf_unit == dev->dv_unit)
553 				cf->cf_fstate = FSTATE_NOTFOUND;
554 #ifdef __BROKEN_CONFIG_UNIT_USAGE
555 			if (cf->cf_fstate == FSTATE_STAR &&
556 			    cf->cf_unit == dev->dv_unit + 1)
557 				cf->cf_unit--;
558 #endif /* __BROKEN_CONFIG_UNIT_USAGE */
559 		}
560 	}
561 
562 	/*
563 	 * Unlink from device list.
564 	 */
565 	TAILQ_REMOVE(&alldevs, dev, dv_list);
566 
567 	/*
568 	 * Remove from cfdriver's array, tell the world, and free softc.
569 	 */
570 	cd->cd_devs[dev->dv_unit] = NULL;
571 	if ((flags & DETACH_QUIET) == 0)
572 		printf("%s detached\n", dev->dv_xname);
573 	free(dev, M_DEVBUF);
574 
575 	/*
576 	 * If the device now has no units in use, deallocate its softc array.
577 	 */
578 	for (i = 0; i < cd->cd_ndevs; i++)
579 		if (cd->cd_devs[i] != NULL)
580 			break;
581 	if (i == cd->cd_ndevs) {		/* nothing found; deallocate */
582 		free(cd->cd_devs, M_DEVBUF);
583 		cd->cd_devs = NULL;
584 		cd->cd_ndevs = 0;
585 	}
586 
587 	/*
588 	 * Return success.
589 	 */
590 	return (0);
591 }
592 
593 int
594 config_activate(struct device *dev)
595 {
596 	struct cfattach *ca = dev->dv_cfdata->cf_attach;
597 	int rv = 0, oflags = dev->dv_flags;
598 
599 	if (ca->ca_activate == NULL)
600 		return (EOPNOTSUPP);
601 
602 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
603 		dev->dv_flags |= DVF_ACTIVE;
604 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
605 		if (rv)
606 			dev->dv_flags = oflags;
607 	}
608 	return (rv);
609 }
610 
611 int
612 config_deactivate(struct device *dev)
613 {
614 	struct cfattach *ca = dev->dv_cfdata->cf_attach;
615 	int rv = 0, oflags = dev->dv_flags;
616 
617 	if (ca->ca_activate == NULL)
618 		return (EOPNOTSUPP);
619 
620 	if (dev->dv_flags & DVF_ACTIVE) {
621 		dev->dv_flags &= ~DVF_ACTIVE;
622 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
623 		if (rv)
624 			dev->dv_flags = oflags;
625 	}
626 	return (rv);
627 }
628 
629 /*
630  * Defer the configuration of the specified device until all
631  * of its parent's devices have been attached.
632  */
633 void
634 config_defer(struct device *dev, void (*func)(struct device *))
635 {
636 	struct deferred_config *dc;
637 
638 	if (dev->dv_parent == NULL)
639 		panic("config_defer: can't defer config of a root device");
640 
641 #ifdef DIAGNOSTIC
642 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
643 	     dc = TAILQ_NEXT(dc, dc_queue)) {
644 		if (dc->dc_dev == dev)
645 			panic("config_defer: deferred twice");
646 	}
647 #endif
648 
649 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
650 	if (dc == NULL)
651 		panic("config_defer: unable to allocate callback");
652 
653 	dc->dc_dev = dev;
654 	dc->dc_func = func;
655 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
656 	config_pending_incr();
657 }
658 
659 /*
660  * Defer some autoconfiguration for a device until after interrupts
661  * are enabled.
662  */
663 void
664 config_interrupts(struct device *dev, void (*func)(struct device *))
665 {
666 	struct deferred_config *dc;
667 
668 	/*
669 	 * If interrupts are enabled, callback now.
670 	 */
671 	if (cold == 0) {
672 		(*func)(dev);
673 		return;
674 	}
675 
676 #ifdef DIAGNOSTIC
677 	for (dc = TAILQ_FIRST(&interrupt_config_queue); dc != NULL;
678 	     dc = TAILQ_NEXT(dc, dc_queue)) {
679 		if (dc->dc_dev == dev)
680 			panic("config_interrupts: deferred twice");
681 	}
682 #endif
683 
684 	dc = malloc(sizeof(*dc), M_DEVBUF, cold ? M_NOWAIT : M_WAITOK);
685 	if (dc == NULL)
686 		panic("config_interrupts: unable to allocate callback");
687 
688 	dc->dc_dev = dev;
689 	dc->dc_func = func;
690 	TAILQ_INSERT_TAIL(&interrupt_config_queue, dc, dc_queue);
691 	config_pending_incr();
692 }
693 
694 /*
695  * Process a deferred configuration queue.
696  */
697 static void
698 config_process_deferred(struct deferred_config_head *queue,
699     struct device *parent)
700 {
701 	struct deferred_config *dc, *ndc;
702 
703 	for (dc = TAILQ_FIRST(queue); dc != NULL; dc = ndc) {
704 		ndc = TAILQ_NEXT(dc, dc_queue);
705 		if (parent == NULL || dc->dc_dev->dv_parent == parent) {
706 			TAILQ_REMOVE(queue, dc, dc_queue);
707 			(*dc->dc_func)(dc->dc_dev);
708 			free(dc, M_DEVBUF);
709 			config_pending_decr();
710 		}
711 	}
712 }
713 
714 /*
715  * Manipulate the config_pending semaphore.
716  */
717 void
718 config_pending_incr(void)
719 {
720 
721 	config_pending++;
722 }
723 
724 void
725 config_pending_decr(void)
726 {
727 
728 #ifdef DIAGNOSTIC
729 	if (config_pending == 0)
730 		panic("config_pending_decr: config_pending == 0");
731 #endif
732 	config_pending--;
733 	if (config_pending == 0)
734 		wakeup((void *)&config_pending);
735 }
736 
737 /*
738  * Attach a statically-initialized event.  The type and string pointers
739  * are already set up.
740  */
741 void
742 evcnt_attach_static(struct evcnt *ev)
743 {
744 	int len;
745 
746 	len = strlen(ev->ev_group);
747 #ifdef DIAGNOSTIC
748 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
749 		panic("evcnt_attach_static: group length (%s)", ev->ev_group);
750 #endif
751 	ev->ev_grouplen = len;
752 
753 	len = strlen(ev->ev_name);
754 #ifdef DIAGNOSTIC
755 	if (len >= EVCNT_STRING_MAX)		/* ..._MAX includes NUL */
756 		panic("evcnt_attach_static: name length (%s)", ev->ev_name);
757 #endif
758 	ev->ev_namelen = len;
759 
760 	TAILQ_INSERT_TAIL(&allevents, ev, ev_list);
761 }
762 
763 /*
764  * Attach a dynamically-initialized event.  Zero it, set up the type
765  * and string pointers and then act like it was statically initialized.
766  */
767 void
768 evcnt_attach_dynamic(struct evcnt *ev, int type, const struct evcnt *parent,
769     const char *group, const char *name)
770 {
771 
772 	memset(ev, 0, sizeof *ev);
773 	ev->ev_type = type;
774 	ev->ev_parent = parent;
775 	ev->ev_group = group;
776 	ev->ev_name = name;
777 	evcnt_attach_static(ev);
778 }
779 
780 /*
781  * Detach an event.
782  */
783 void
784 evcnt_detach(struct evcnt *ev)
785 {
786 
787 	TAILQ_REMOVE(&allevents, ev, ev_list);
788 }
789