xref: /netbsd-src/sys/kern/subr_autoconf.c (revision dc306354b0b29af51801a7632f1e95265a68cd81)
1 /*	$NetBSD: subr_autoconf.c,v 1.37 1998/12/03 23:50:39 pk Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This software was developed by the Computer Systems Engineering group
8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9  * contributed to Berkeley.
10  *
11  * All advertising materials mentioning features or use of this software
12  * must display the following acknowledgement:
13  *	This product includes software developed by the University of
14  *	California, Lawrence Berkeley Laboratories.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. All advertising materials mentioning features or use of this software
25  *    must display the following acknowledgement:
26  *	This product includes software developed by the University of
27  *	California, Berkeley and its contributors.
28  * 4. Neither the name of the University nor the names of its contributors
29  *    may be used to endorse or promote products derived from this software
30  *    without specific prior written permission.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
33  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
36  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42  * SUCH DAMAGE.
43  *
44  * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp  (LBL)
45  *
46  *	@(#)subr_autoconf.c	8.3 (Berkeley) 5/17/94
47  */
48 
49 #include <sys/param.h>
50 #include <sys/device.h>
51 #include <sys/malloc.h>
52 #include <sys/systm.h>
53 #include <sys/errno.h>
54 #include <machine/limits.h>
55 
56 /*
57  * Autoconfiguration subroutines.
58  */
59 
60 /*
61  * ioconf.c exports exactly two names: cfdata and cfroots.  All system
62  * devices and drivers are found via these tables.
63  */
64 extern struct cfdata cfdata[];
65 extern short cfroots[];
66 
67 #define	ROOT ((struct device *)NULL)
68 
69 struct matchinfo {
70 	cfmatch_t fn;
71 	struct	device *parent;
72 	void	*aux;
73 	struct	cfdata *match;
74 	int	pri;
75 };
76 
77 static char *number __P((char *, int));
78 static void mapply __P((struct matchinfo *, struct cfdata *));
79 
80 struct deferred_config {
81 	TAILQ_ENTRY(deferred_config) dc_queue;
82 	struct device *dc_dev;
83 	void (*dc_func) __P((struct device *));
84 };
85 
86 TAILQ_HEAD(, deferred_config) deferred_config_queue;
87 
88 static void config_process_deferred_children __P((struct device *));
89 
90 struct devicelist alldevs;		/* list of all devices */
91 struct evcntlist allevents;		/* list of all event counters */
92 
93 /*
94  * Initialize autoconfiguration data structures.
95  */
96 void
97 config_init()
98 {
99 
100 	TAILQ_INIT(&deferred_config_queue);
101 	TAILQ_INIT(&alldevs);
102 	TAILQ_INIT(&allevents);
103 }
104 
105 /*
106  * Apply the matching function and choose the best.  This is used
107  * a few times and we want to keep the code small.
108  */
109 static void
110 mapply(m, cf)
111 	register struct matchinfo *m;
112 	register struct cfdata *cf;
113 {
114 	register int pri;
115 
116 	if (m->fn != NULL)
117 		pri = (*m->fn)(m->parent, cf, m->aux);
118 	else {
119 	        if (cf->cf_attach->ca_match == NULL) {
120 			panic("mapply: no match function for '%s' device\n",
121 			    cf->cf_driver->cd_name);
122 		}
123 		pri = (*cf->cf_attach->ca_match)(m->parent, cf, m->aux);
124 	}
125 	if (pri > m->pri) {
126 		m->match = cf;
127 		m->pri = pri;
128 	}
129 }
130 
131 /*
132  * Iterate over all potential children of some device, calling the given
133  * function (default being the child's match function) for each one.
134  * Nonzero returns are matches; the highest value returned is considered
135  * the best match.  Return the `found child' if we got a match, or NULL
136  * otherwise.  The `aux' pointer is simply passed on through.
137  *
138  * Note that this function is designed so that it can be used to apply
139  * an arbitrary function to all potential children (its return value
140  * can be ignored).
141  */
142 struct cfdata *
143 config_search(fn, parent, aux)
144 	cfmatch_t fn;
145 	register struct device *parent;
146 	void *aux;
147 {
148 	register struct cfdata *cf;
149 	register short *p;
150 	struct matchinfo m;
151 
152 	m.fn = fn;
153 	m.parent = parent;
154 	m.aux = aux;
155 	m.match = NULL;
156 	m.pri = 0;
157 	for (cf = cfdata; cf->cf_driver; cf++) {
158 		/*
159 		 * Skip cf if no longer eligible, otherwise scan through
160 		 * parents for one matching `parent', and try match function.
161 		 */
162 		if (cf->cf_fstate == FSTATE_FOUND)
163 			continue;
164 		for (p = cf->cf_parents; *p >= 0; p++)
165 			if (parent->dv_cfdata == &cfdata[*p])
166 				mapply(&m, cf);
167 	}
168 	return (m.match);
169 }
170 
171 /*
172  * Find the given root device.
173  * This is much like config_search, but there is no parent.
174  */
175 struct cfdata *
176 config_rootsearch(fn, rootname, aux)
177 	register cfmatch_t fn;
178 	register char *rootname;
179 	register void *aux;
180 {
181 	register struct cfdata *cf;
182 	register short *p;
183 	struct matchinfo m;
184 
185 	m.fn = fn;
186 	m.parent = ROOT;
187 	m.aux = aux;
188 	m.match = NULL;
189 	m.pri = 0;
190 	/*
191 	 * Look at root entries for matching name.  We do not bother
192 	 * with found-state here since only one root should ever be
193 	 * searched (and it must be done first).
194 	 */
195 	for (p = cfroots; *p >= 0; p++) {
196 		cf = &cfdata[*p];
197 		if (strcmp(cf->cf_driver->cd_name, rootname) == 0)
198 			mapply(&m, cf);
199 	}
200 	return (m.match);
201 }
202 
203 static char *msgs[3] = { "", " not configured\n", " unsupported\n" };
204 
205 /*
206  * The given `aux' argument describes a device that has been found
207  * on the given parent, but not necessarily configured.  Locate the
208  * configuration data for that device (using the submatch function
209  * provided, or using candidates' cd_match configuration driver
210  * functions) and attach it, and return true.  If the device was
211  * not configured, call the given `print' function and return 0.
212  */
213 struct device *
214 config_found_sm(parent, aux, print, submatch)
215 	struct device *parent;
216 	void *aux;
217 	cfprint_t print;
218 	cfmatch_t submatch;
219 {
220 	struct cfdata *cf;
221 
222 	if ((cf = config_search(submatch, parent, aux)) != NULL)
223 		return (config_attach(parent, cf, aux, print));
224 	if (print)
225 		printf(msgs[(*print)(aux, parent->dv_xname)]);
226 	return (NULL);
227 }
228 
229 /*
230  * As above, but for root devices.
231  */
232 struct device *
233 config_rootfound(rootname, aux)
234 	char *rootname;
235 	void *aux;
236 {
237 	struct cfdata *cf;
238 
239 	if ((cf = config_rootsearch((cfmatch_t)NULL, rootname, aux)) != NULL)
240 		return (config_attach(ROOT, cf, aux, (cfprint_t)NULL));
241 	printf("root device %s not configured\n", rootname);
242 	return (NULL);
243 }
244 
245 /* just like sprintf(buf, "%d") except that it works from the end */
246 static char *
247 number(ep, n)
248 	register char *ep;
249 	register int n;
250 {
251 
252 	*--ep = 0;
253 	while (n >= 10) {
254 		*--ep = (n % 10) + '0';
255 		n /= 10;
256 	}
257 	*--ep = n + '0';
258 	return (ep);
259 }
260 
261 /*
262  * Attach a found device.  Allocates memory for device variables.
263  */
264 struct device *
265 config_attach(parent, cf, aux, print)
266 	register struct device *parent;
267 	register struct cfdata *cf;
268 	register void *aux;
269 	cfprint_t print;
270 {
271 	register struct device *dev;
272 	register struct cfdriver *cd;
273 	register struct cfattach *ca;
274 	register size_t lname, lunit;
275 	register char *xunit;
276 	int myunit;
277 	char num[10];
278 
279 	cd = cf->cf_driver;
280 	ca = cf->cf_attach;
281 	if (ca->ca_devsize < sizeof(struct device))
282 		panic("config_attach");
283 	myunit = cf->cf_unit;
284 	if (cf->cf_fstate == FSTATE_STAR)
285 		cf->cf_unit++;
286 	else {
287 		KASSERT(cf->cf_fstate == FSTATE_NOTFOUND);
288 		cf->cf_fstate = FSTATE_FOUND;
289 	}
290 
291 	/* compute length of name and decimal expansion of unit number */
292 	lname = strlen(cd->cd_name);
293 	xunit = number(&num[sizeof(num)], myunit);
294 	lunit = &num[sizeof(num)] - xunit;
295 	if (lname + lunit >= sizeof(dev->dv_xname))
296 		panic("config_attach: device name too long");
297 
298 	/* get memory for all device vars */
299 	dev = (struct device *)malloc(ca->ca_devsize, M_DEVBUF, M_NOWAIT);
300 	if (!dev)
301 	    panic("config_attach: memory allocation for device softc failed");
302 	memset(dev, 0, ca->ca_devsize);
303 	TAILQ_INSERT_TAIL(&alldevs, dev, dv_list);	/* link up */
304 	dev->dv_class = cd->cd_class;
305 	dev->dv_cfdata = cf;
306 	dev->dv_unit = myunit;
307 	memcpy(dev->dv_xname, cd->cd_name, lname);
308 	memcpy(dev->dv_xname + lname, xunit, lunit);
309 	dev->dv_parent = parent;
310 	dev->dv_flags = DVF_ACTIVE;	/* always initially active */
311 
312 	if (parent == ROOT)
313 		printf("%s (root)", dev->dv_xname);
314 	else {
315 		printf("%s at %s", dev->dv_xname, parent->dv_xname);
316 		if (print)
317 			(void) (*print)(aux, (char *)0);
318 	}
319 
320 	/* put this device in the devices array */
321 	if (dev->dv_unit >= cd->cd_ndevs) {
322 		/*
323 		 * Need to expand the array.
324 		 */
325 		int old = cd->cd_ndevs, new;
326 		void **nsp;
327 
328 		if (old == 0)
329 			new = MINALLOCSIZE / sizeof(void *);
330 		else
331 			new = old * 2;
332 		while (new <= dev->dv_unit)
333 			new *= 2;
334 		cd->cd_ndevs = new;
335 		nsp = malloc(new * sizeof(void *), M_DEVBUF, M_NOWAIT);
336 		if (nsp == 0)
337 			panic("config_attach: %sing dev array",
338 			    old != 0 ? "expand" : "creat");
339 		memset(nsp + old, 0, (new - old) * sizeof(void *));
340 		if (old != 0) {
341 			memcpy(nsp, cd->cd_devs, old * sizeof(void *));
342 			free(cd->cd_devs, M_DEVBUF);
343 		}
344 		cd->cd_devs = nsp;
345 	}
346 	if (cd->cd_devs[dev->dv_unit])
347 		panic("config_attach: duplicate %s", dev->dv_xname);
348 	cd->cd_devs[dev->dv_unit] = dev;
349 
350 	/*
351 	 * Before attaching, clobber any unfound devices that are
352 	 * otherwise identical, or bump the unit number on all starred
353 	 * cfdata for this device.
354 	 */
355 	for (cf = cfdata; cf->cf_driver; cf++)
356 		if (cf->cf_driver == cd && cf->cf_unit == dev->dv_unit) {
357 			if (cf->cf_fstate == FSTATE_NOTFOUND)
358 				cf->cf_fstate = FSTATE_FOUND;
359 			if (cf->cf_fstate == FSTATE_STAR)
360 				cf->cf_unit++;
361 		}
362 #if defined(__alpha__) || defined(hp300) || defined(__i386__) || defined(__sparc__)
363 	device_register(dev, aux);
364 #endif
365 	(*ca->ca_attach)(parent, dev, aux);
366 	config_process_deferred_children(dev);
367 	return (dev);
368 }
369 
370 /*
371  * Detach a device.  Optionally forced (e.g. because of hardware
372  * removal) and quiet.  Returns zero if successful, non-zero
373  * (an error code) otherwise.
374  *
375  * Note that this code wants to be run from a process context, so
376  * that the detach can sleep to allow processes which have a device
377  * open to run and unwind their stacks.
378  */
379 int
380 config_detach(dev, flags)
381 	struct device *dev;
382 	int flags;
383 {
384 	struct cfdata *cf;
385 	struct cfattach *ca;
386 	struct cfdriver *cd;
387 #ifdef DIAGNOSTIC
388 	struct device *d;
389 #endif
390 	int rv = 0, i;
391 
392 	cf = dev->dv_cfdata;
393 #ifdef DIAGNOSTIC
394 	if (cf->cf_fstate != FSTATE_FOUND && cf->cf_fstate != FSTATE_STAR)
395 		panic("config_detach: bad device fstate");
396 #endif
397 	ca = cf->cf_attach;
398 	cd = cf->cf_driver;
399 
400 	/*
401 	 * Ensure the device is deactivated.  If the device doesn't
402 	 * have an activation entry point, we allow DVF_ACTIVE to
403 	 * remain set.  Otherwise, if DVF_ACTIVE is still set, the
404 	 * device is busy, and the detach fails.
405 	 */
406 	if (ca->ca_activate != NULL)
407 		rv = config_deactivate(dev);
408 
409 	/*
410 	 * Try to detach the device.  If that's not possible, then
411 	 * we either panic() (for the forced but failed case), or
412 	 * return an error.
413 	 */
414 	if (rv == 0) {
415 		if (ca->ca_detach != NULL)
416 			rv = (*ca->ca_detach)(dev, flags);
417 		else
418 			rv = EOPNOTSUPP;
419 	}
420 	if (rv != 0) {
421 		if ((flags & DETACH_FORCE) == 0)
422 			return (rv);
423 		else
424 			panic("config_detach: forced detach of %s failed (%d)",
425 			    dev->dv_xname, rv);
426 	}
427 
428 	/*
429 	 * The device has now been successfully detached.
430 	 */
431 
432 #ifdef DIAGNOSTIC
433 	/*
434 	 * Sanity: If you're successfully detached, you should have no
435 	 * children.  (Note that because children must be attached
436 	 * after parents, we only need to search the latter part of
437 	 * the list.)
438 	 */
439 	for (d = TAILQ_NEXT(dev, dv_list); d != NULL;
440 	     d = TAILQ_NEXT(d, dv_list)) {
441 		if (d->dv_parent == dev)
442 			panic("config_detach: detached device has children");
443 	}
444 #endif
445 
446 	/*
447 	 * Mark cfdata to show that the unit can be reused, if possible.
448 	 * Note that we can only re-use a starred unit number if the unit
449 	 * being detached had the last assigned unit number.
450 	 */
451 	for (cf = cfdata; cf->cf_driver; cf++) {
452 		if (cf->cf_driver == cd) {
453 			if (cf->cf_fstate == FSTATE_FOUND &&
454 			    cf->cf_unit == dev->dv_unit)
455 				cf->cf_fstate = FSTATE_NOTFOUND;
456 			if (cf->cf_fstate == FSTATE_STAR &&
457 			    cf->cf_unit == dev->dv_unit + 1)
458 				cf->cf_unit--;
459 		}
460 	}
461 
462 	/*
463 	 * Unlink from device list.
464 	 */
465 	TAILQ_REMOVE(&alldevs, dev, dv_list);
466 
467 	/*
468 	 * Remove from cfdriver's array, tell the world, and free softc.
469 	 */
470 	cd->cd_devs[dev->dv_unit] = NULL;
471 	if ((flags & DETACH_QUIET) == 0)
472 		printf("%s detached\n", dev->dv_xname);
473 	free(dev, M_DEVBUF);
474 
475 	/*
476 	 * If the device now has no units in use, deallocate its softc array.
477 	 */
478 	for (i = 0; i < cd->cd_ndevs; i++)
479 		if (cd->cd_devs[i] != NULL)
480 			break;
481 	if (i == cd->cd_ndevs) {		/* nothing found; deallocate */
482 		free(cd->cd_devs, M_DEVBUF);
483 		cd->cd_devs = NULL;
484 		cd->cd_ndevs = 0;
485 	}
486 
487 	/*
488 	 * Return success.
489 	 */
490 	return (0);
491 }
492 
493 int
494 config_activate(dev)
495 	struct device *dev;
496 {
497 	struct cfattach *ca = dev->dv_cfdata->cf_attach;
498 	int rv = 0, oflags = dev->dv_flags;
499 
500 	if (ca->ca_activate == NULL)
501 		return (EOPNOTSUPP);
502 
503 	if ((dev->dv_flags & DVF_ACTIVE) == 0) {
504 		dev->dv_flags |= DVF_ACTIVE;
505 		rv = (*ca->ca_activate)(dev, DVACT_ACTIVATE);
506 		if (rv)
507 			dev->dv_flags = oflags;
508 	}
509 	return (rv);
510 }
511 
512 int
513 config_deactivate(dev)
514 	struct device *dev;
515 {
516 	struct cfattach *ca = dev->dv_cfdata->cf_attach;
517 	int rv = 0, oflags = dev->dv_flags;
518 
519 	if (ca->ca_activate == NULL)
520 		return (EOPNOTSUPP);
521 
522 	if (dev->dv_flags & DVF_ACTIVE) {
523 		dev->dv_flags &= ~DVF_ACTIVE;
524 		rv = (*ca->ca_activate)(dev, DVACT_DEACTIVATE);
525 		if (rv)
526 			dev->dv_flags = oflags;
527 	}
528 	return (rv);
529 }
530 
531 /*
532  * Defer the configuration of the specified device until all
533  * of its parent's devices have been attached.
534  */
535 void
536 config_defer(dev, func)
537 	struct device *dev;
538 	void (*func) __P((struct device *));
539 {
540 	struct deferred_config *dc;
541 
542 	if (dev->dv_parent == NULL)
543 		panic("config_defer: can't defer config of a root device");
544 
545 #ifdef DIAGNOSTIC
546 	for (dc = TAILQ_FIRST(&deferred_config_queue); dc != NULL;
547 	     dc = TAILQ_NEXT(dc, dc_queue)) {
548 		if (dc->dc_dev == dev)
549 			panic("config_defer: deferred twice");
550 	}
551 #endif
552 
553 	if ((dc = malloc(sizeof(*dc), M_DEVBUF, M_NOWAIT)) == NULL)
554 		panic("config_defer: can't allocate defer structure");
555 
556 	dc->dc_dev = dev;
557 	dc->dc_func = func;
558 	TAILQ_INSERT_TAIL(&deferred_config_queue, dc, dc_queue);
559 }
560 
561 /*
562  * Process the deferred configuration queue for a device.
563  */
564 static void
565 config_process_deferred_children(parent)
566 	struct device *parent;
567 {
568 	struct deferred_config *dc, *ndc;
569 
570 	for (dc = TAILQ_FIRST(&deferred_config_queue);
571 	     dc != NULL; dc = ndc) {
572 		ndc = TAILQ_NEXT(dc, dc_queue);
573 		if (dc->dc_dev->dv_parent == parent) {
574 			TAILQ_REMOVE(&deferred_config_queue, dc, dc_queue);
575 			(*dc->dc_func)(dc->dc_dev);
576 			free(dc, M_DEVBUF);
577 		}
578 	}
579 }
580 
581 /*
582  * Attach an event.  These must come from initially-zero space (see
583  * commented-out assignments below), but that occurs naturally for
584  * device instance variables.
585  */
586 void
587 evcnt_attach(dev, name, ev)
588 	struct device *dev;
589 	const char *name;
590 	struct evcnt *ev;
591 {
592 
593 #ifdef DIAGNOSTIC
594 	if (strlen(name) >= sizeof(ev->ev_name))
595 		panic("evcnt_attach");
596 #endif
597 	/* ev->ev_next = NULL; */
598 	ev->ev_dev = dev;
599 	/* ev->ev_count = 0; */
600 	strcpy(ev->ev_name, name);
601 	TAILQ_INSERT_TAIL(&allevents, ev, ev_list);
602 }
603 
604 /*
605  * Detach an event.
606  */
607 void
608 evcnt_detach(ev)
609 	struct evcnt *ev;
610 {
611 
612 	TAILQ_REMOVE(&allevents, ev, ev_list);
613 }
614