acpi_machdep.c revision 197536
1/*-
2 * Copyright (c) 2001 Mitsuru IWASAKI
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/amd64/acpica/acpi_machdep.c 197536 2009-09-27 14:00:16Z jkim $");
29
30#include <sys/param.h>
31#include <sys/bus.h>
32#include <sys/kernel.h>
33#include <sys/module.h>
34#include <sys/sysctl.h>
35#include <vm/vm.h>
36#include <vm/pmap.h>
37
38#include <contrib/dev/acpica/include/acpi.h>
39#include <contrib/dev/acpica/include/accommon.h>
40#include <contrib/dev/acpica/include/actables.h>
41
42#include <dev/acpica/acpivar.h>
43
44#include <machine/nexusvar.h>
45
46/*
47 * APM driver emulation
48 */
49
50#include <sys/condvar.h>
51#include <sys/conf.h>
52#include <sys/fcntl.h>
53#include <sys/malloc.h>
54#include <sys/poll.h>
55#include <sys/uio.h>
56
57#include <dev/acpica/acpiio.h>
58
59#include <machine/apm_bios.h>
60#include <i386/include/pc/bios.h>
61
62#include <i386/bios/apm.h>
63
64SYSCTL_DECL(_debug_acpi);
65
66int acpi_resume_beep;
67TUNABLE_INT("debug.acpi.resume_beep", &acpi_resume_beep);
68SYSCTL_INT(_debug_acpi, OID_AUTO, resume_beep, CTLFLAG_RW, &acpi_resume_beep,
69    0, "Beep the PC speaker when resuming");
70
71int acpi_reset_video;
72TUNABLE_INT("hw.acpi.reset_video", &acpi_reset_video);
73
74static int intr_model = ACPI_INTR_PIC;
75static int apm_active;
76static struct clonedevs *apm_clones;
77
78MALLOC_DEFINE(M_APMDEV, "apmdev", "APM device emulation");
79
80static d_open_t		apmopen;
81static d_close_t	apmclose;
82static d_write_t	apmwrite;
83static d_ioctl_t	apmioctl;
84static d_poll_t		apmpoll;
85static d_kqfilter_t	apmkqfilter;
86static void		apmreadfiltdetach(struct knote *kn);
87static int		apmreadfilt(struct knote *kn, long hint);
88static struct filterops	apm_readfiltops = {
89	.f_isfd = 1,
90	.f_detach = apmreadfiltdetach,
91	.f_event = apmreadfilt,
92};
93
94static struct cdevsw apm_cdevsw = {
95	.d_version =	D_VERSION,
96	.d_flags =	D_TRACKCLOSE | D_NEEDMINOR,
97	.d_open =	apmopen,
98	.d_close =	apmclose,
99	.d_write =	apmwrite,
100	.d_ioctl =	apmioctl,
101	.d_poll =	apmpoll,
102	.d_name =	"apm",
103	.d_kqfilter =	apmkqfilter
104};
105
106static int
107acpi_capm_convert_battstate(struct  acpi_battinfo *battp)
108{
109	int	state;
110
111	state = APM_UNKNOWN;
112
113	if (battp->state & ACPI_BATT_STAT_DISCHARG) {
114		if (battp->cap >= 50)
115			state = 0;	/* high */
116		else
117			state = 1;	/* low */
118	}
119	if (battp->state & ACPI_BATT_STAT_CRITICAL)
120		state = 2;		/* critical */
121	if (battp->state & ACPI_BATT_STAT_CHARGING)
122		state = 3;		/* charging */
123
124	/* If still unknown, determine it based on the battery capacity. */
125	if (state == APM_UNKNOWN) {
126		if (battp->cap >= 50)
127			state = 0;	/* high */
128		else
129			state = 1;	/* low */
130	}
131
132	return (state);
133}
134
135static int
136acpi_capm_convert_battflags(struct  acpi_battinfo *battp)
137{
138	int	flags;
139
140	flags = 0;
141
142	if (battp->cap >= 50)
143		flags |= APM_BATT_HIGH;
144	else {
145		if (battp->state & ACPI_BATT_STAT_CRITICAL)
146			flags |= APM_BATT_CRITICAL;
147		else
148			flags |= APM_BATT_LOW;
149	}
150	if (battp->state & ACPI_BATT_STAT_CHARGING)
151		flags |= APM_BATT_CHARGING;
152	if (battp->state == ACPI_BATT_STAT_NOT_PRESENT)
153		flags = APM_BATT_NOT_PRESENT;
154
155	return (flags);
156}
157
158static int
159acpi_capm_get_info(apm_info_t aip)
160{
161	int	acline;
162	struct	acpi_battinfo batt;
163
164	aip->ai_infoversion = 1;
165	aip->ai_major       = 1;
166	aip->ai_minor       = 2;
167	aip->ai_status      = apm_active;
168	aip->ai_capabilities= 0xff00;	/* unknown */
169
170	if (acpi_acad_get_acline(&acline))
171		aip->ai_acline = APM_UNKNOWN;	/* unknown */
172	else
173		aip->ai_acline = acline;	/* on/off */
174
175	if (acpi_battery_get_battinfo(NULL, &batt) != 0) {
176		aip->ai_batt_stat = APM_UNKNOWN;
177		aip->ai_batt_life = APM_UNKNOWN;
178		aip->ai_batt_time = -1;		 /* unknown */
179		aip->ai_batteries = ~0U;	 /* unknown */
180	} else {
181		aip->ai_batt_stat = acpi_capm_convert_battstate(&batt);
182		aip->ai_batt_life = batt.cap;
183		aip->ai_batt_time = (batt.min == -1) ? -1 : batt.min * 60;
184		aip->ai_batteries = acpi_battery_get_units();
185	}
186
187	return (0);
188}
189
190static int
191acpi_capm_get_pwstatus(apm_pwstatus_t app)
192{
193	device_t dev;
194	int	acline, unit, error;
195	struct	acpi_battinfo batt;
196
197	if (app->ap_device != PMDV_ALLDEV &&
198	    (app->ap_device < PMDV_BATT0 || app->ap_device > PMDV_BATT_ALL))
199		return (1);
200
201	if (app->ap_device == PMDV_ALLDEV)
202		error = acpi_battery_get_battinfo(NULL, &batt);
203	else {
204		unit = app->ap_device - PMDV_BATT0;
205		dev = devclass_get_device(devclass_find("battery"), unit);
206		if (dev != NULL)
207			error = acpi_battery_get_battinfo(dev, &batt);
208		else
209			error = ENXIO;
210	}
211	if (error)
212		return (1);
213
214	app->ap_batt_stat = acpi_capm_convert_battstate(&batt);
215	app->ap_batt_flag = acpi_capm_convert_battflags(&batt);
216	app->ap_batt_life = batt.cap;
217	app->ap_batt_time = (batt.min == -1) ? -1 : batt.min * 60;
218
219	if (acpi_acad_get_acline(&acline))
220		app->ap_acline = APM_UNKNOWN;
221	else
222		app->ap_acline = acline;	/* on/off */
223
224	return (0);
225}
226
227/* Create single-use devices for /dev/apm and /dev/apmctl. */
228static void
229apm_clone(void *arg, struct ucred *cred, char *name, int namelen,
230    struct cdev **dev)
231{
232	int ctl_dev, unit;
233
234	if (*dev != NULL)
235		return;
236	if (strcmp(name, "apmctl") == 0)
237		ctl_dev = TRUE;
238	else if (strcmp(name, "apm") == 0)
239		ctl_dev = FALSE;
240	else
241		return;
242
243	/* Always create a new device and unit number. */
244	unit = -1;
245	if (clone_create(&apm_clones, &apm_cdevsw, &unit, dev, 0)) {
246		if (ctl_dev) {
247			*dev = make_dev(&apm_cdevsw, unit,
248			    UID_ROOT, GID_OPERATOR, 0660, "apmctl%d", unit);
249		} else {
250			*dev = make_dev(&apm_cdevsw, unit,
251			    UID_ROOT, GID_OPERATOR, 0664, "apm%d", unit);
252		}
253		if (*dev != NULL) {
254			dev_ref(*dev);
255			(*dev)->si_flags |= SI_CHEAPCLONE;
256		}
257	}
258}
259
260/* Create a struct for tracking per-device suspend notification. */
261static struct apm_clone_data *
262apm_create_clone(struct cdev *dev, struct acpi_softc *acpi_sc)
263{
264	struct apm_clone_data *clone;
265
266	clone = malloc(sizeof(*clone), M_APMDEV, M_WAITOK);
267	clone->cdev = dev;
268	clone->acpi_sc = acpi_sc;
269	clone->notify_status = APM_EV_NONE;
270	bzero(&clone->sel_read, sizeof(clone->sel_read));
271	knlist_init_mtx(&clone->sel_read.si_note, &acpi_mutex);
272
273	/*
274	 * The acpi device is always managed by devd(8) and is considered
275	 * writable (i.e., ack is required to allow suspend to proceed.)
276	 */
277	if (strcmp("acpi", devtoname(dev)) == 0)
278		clone->flags = ACPI_EVF_DEVD | ACPI_EVF_WRITE;
279	else
280		clone->flags = ACPI_EVF_NONE;
281
282	ACPI_LOCK(acpi);
283	STAILQ_INSERT_TAIL(&acpi_sc->apm_cdevs, clone, entries);
284	ACPI_UNLOCK(acpi);
285	return (clone);
286}
287
288static int
289apmopen(struct cdev *dev, int flag, int fmt, struct thread *td)
290{
291	struct	acpi_softc *acpi_sc;
292	struct 	apm_clone_data *clone;
293
294	acpi_sc = devclass_get_softc(devclass_find("acpi"), 0);
295	clone = apm_create_clone(dev, acpi_sc);
296	dev->si_drv1 = clone;
297
298	/* If the device is opened for write, record that. */
299	if ((flag & FWRITE) != 0)
300		clone->flags |= ACPI_EVF_WRITE;
301
302	return (0);
303}
304
305static int
306apmclose(struct cdev *dev, int flag, int fmt, struct thread *td)
307{
308	struct	apm_clone_data *clone;
309	struct	acpi_softc *acpi_sc;
310
311	clone = dev->si_drv1;
312	acpi_sc = clone->acpi_sc;
313
314	/* We are about to lose a reference so check if suspend should occur */
315	if (acpi_sc->acpi_next_sstate != 0 &&
316	    clone->notify_status != APM_EV_ACKED)
317		acpi_AckSleepState(clone, 0);
318
319	/* Remove this clone's data from the list and free it. */
320	ACPI_LOCK(acpi);
321	STAILQ_REMOVE(&acpi_sc->apm_cdevs, clone, apm_clone_data, entries);
322	knlist_destroy(&clone->sel_read.si_note);
323	ACPI_UNLOCK(acpi);
324	free(clone, M_APMDEV);
325	destroy_dev_sched(dev);
326	return (0);
327}
328
329static int
330apmioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
331{
332	int	error;
333	struct	apm_clone_data *clone;
334	struct	acpi_softc *acpi_sc;
335	struct	apm_info info;
336	struct 	apm_event_info *ev_info;
337	apm_info_old_t aiop;
338
339	error = 0;
340	clone = dev->si_drv1;
341	acpi_sc = clone->acpi_sc;
342
343	switch (cmd) {
344	case APMIO_SUSPEND:
345		if ((flag & FWRITE) == 0)
346			return (EPERM);
347		if (acpi_sc->acpi_next_sstate == 0) {
348			if (acpi_sc->acpi_suspend_sx != ACPI_STATE_S5) {
349				error = acpi_ReqSleepState(acpi_sc,
350				    acpi_sc->acpi_suspend_sx);
351			} else {
352				printf(
353			"power off via apm suspend not supported\n");
354				error = ENXIO;
355			}
356		} else
357			error = acpi_AckSleepState(clone, 0);
358		break;
359	case APMIO_STANDBY:
360		if ((flag & FWRITE) == 0)
361			return (EPERM);
362		if (acpi_sc->acpi_next_sstate == 0) {
363			if (acpi_sc->acpi_standby_sx != ACPI_STATE_S5) {
364				error = acpi_ReqSleepState(acpi_sc,
365				    acpi_sc->acpi_standby_sx);
366			} else {
367				printf(
368			"power off via apm standby not supported\n");
369				error = ENXIO;
370			}
371		} else
372			error = acpi_AckSleepState(clone, 0);
373		break;
374	case APMIO_NEXTEVENT:
375		printf("apm nextevent start\n");
376		ACPI_LOCK(acpi);
377		if (acpi_sc->acpi_next_sstate != 0 && clone->notify_status ==
378		    APM_EV_NONE) {
379			ev_info = (struct apm_event_info *)addr;
380			if (acpi_sc->acpi_next_sstate <= ACPI_STATE_S3)
381				ev_info->type = PMEV_STANDBYREQ;
382			else
383				ev_info->type = PMEV_SUSPENDREQ;
384			ev_info->index = 0;
385			clone->notify_status = APM_EV_NOTIFIED;
386			printf("apm event returning %d\n", ev_info->type);
387		} else
388			error = EAGAIN;
389		ACPI_UNLOCK(acpi);
390		break;
391	case APMIO_GETINFO_OLD:
392		if (acpi_capm_get_info(&info))
393			error = ENXIO;
394		aiop = (apm_info_old_t)addr;
395		aiop->ai_major = info.ai_major;
396		aiop->ai_minor = info.ai_minor;
397		aiop->ai_acline = info.ai_acline;
398		aiop->ai_batt_stat = info.ai_batt_stat;
399		aiop->ai_batt_life = info.ai_batt_life;
400		aiop->ai_status = info.ai_status;
401		break;
402	case APMIO_GETINFO:
403		if (acpi_capm_get_info((apm_info_t)addr))
404			error = ENXIO;
405		break;
406	case APMIO_GETPWSTATUS:
407		if (acpi_capm_get_pwstatus((apm_pwstatus_t)addr))
408			error = ENXIO;
409		break;
410	case APMIO_ENABLE:
411		if ((flag & FWRITE) == 0)
412			return (EPERM);
413		apm_active = 1;
414		break;
415	case APMIO_DISABLE:
416		if ((flag & FWRITE) == 0)
417			return (EPERM);
418		apm_active = 0;
419		break;
420	case APMIO_HALTCPU:
421		break;
422	case APMIO_NOTHALTCPU:
423		break;
424	case APMIO_DISPLAY:
425		if ((flag & FWRITE) == 0)
426			return (EPERM);
427		break;
428	case APMIO_BIOS:
429		if ((flag & FWRITE) == 0)
430			return (EPERM);
431		bzero(addr, sizeof(struct apm_bios_arg));
432		break;
433	default:
434		error = EINVAL;
435		break;
436	}
437
438	return (error);
439}
440
441static int
442apmwrite(struct cdev *dev, struct uio *uio, int ioflag)
443{
444	return (uio->uio_resid);
445}
446
447static int
448apmpoll(struct cdev *dev, int events, struct thread *td)
449{
450	struct	apm_clone_data *clone;
451	int revents;
452
453	revents = 0;
454	ACPI_LOCK(acpi);
455	clone = dev->si_drv1;
456	if (clone->acpi_sc->acpi_next_sstate)
457		revents |= events & (POLLIN | POLLRDNORM);
458	else
459		selrecord(td, &clone->sel_read);
460	ACPI_UNLOCK(acpi);
461	return (revents);
462}
463
464static int
465apmkqfilter(struct cdev *dev, struct knote *kn)
466{
467	struct	apm_clone_data *clone;
468
469	ACPI_LOCK(acpi);
470	clone = dev->si_drv1;
471	kn->kn_hook = clone;
472	kn->kn_fop = &apm_readfiltops;
473	knlist_add(&clone->sel_read.si_note, kn, 0);
474	ACPI_UNLOCK(acpi);
475	return (0);
476}
477
478static void
479apmreadfiltdetach(struct knote *kn)
480{
481	struct	apm_clone_data *clone;
482
483	ACPI_LOCK(acpi);
484	clone = kn->kn_hook;
485	knlist_remove(&clone->sel_read.si_note, kn, 0);
486	ACPI_UNLOCK(acpi);
487}
488
489static int
490apmreadfilt(struct knote *kn, long hint)
491{
492	struct	apm_clone_data *clone;
493	int	sleeping;
494
495	ACPI_LOCK(acpi);
496	clone = kn->kn_hook;
497	sleeping = clone->acpi_sc->acpi_next_sstate ? 1 : 0;
498	ACPI_UNLOCK(acpi);
499	return (sleeping);
500}
501
502int
503acpi_machdep_init(device_t dev)
504{
505	struct acpi_softc	*sc;
506
507	sc = devclass_get_softc(devclass_find("acpi"), 0);
508
509	/* Create a clone for /dev/acpi also. */
510	STAILQ_INIT(&sc->apm_cdevs);
511	sc->acpi_clone = apm_create_clone(sc->acpi_dev_t, sc);
512	clone_setup(&apm_clones);
513	EVENTHANDLER_REGISTER(dev_clone, apm_clone, 0, 1000);
514	acpi_install_wakeup_handler(sc);
515
516	if (intr_model != ACPI_INTR_PIC)
517		acpi_SetIntrModel(intr_model);
518
519	SYSCTL_ADD_UINT(&sc->acpi_sysctl_ctx,
520	    SYSCTL_CHILDREN(sc->acpi_sysctl_tree), OID_AUTO,
521	    "reset_video", CTLFLAG_RW, &acpi_reset_video, 0,
522	    "Call the VESA reset BIOS vector on the resume path");
523
524	return (0);
525}
526
527void
528acpi_SetDefaultIntrModel(int model)
529{
530
531	intr_model = model;
532}
533
534int
535acpi_machdep_quirks(int *quirks)
536{
537	return (0);
538}
539
540void
541acpi_cpu_c1()
542{
543	__asm __volatile("sti; hlt");
544}
545
546/*
547 * Support for mapping ACPI tables during early boot.  Currently this
548 * uses the crashdump map to map each table.  However, the crashdump
549 * map is created in pmap_bootstrap() right after the direct map, so
550 * we should be able to just use pmap_mapbios() here instead.
551 *
552 * This makes the following assumptions about how we use this KVA:
553 * pages 0 and 1 are used to map in the header of each table found via
554 * the RSDT or XSDT and pages 2 to n are used to map in the RSDT or
555 * XSDT.  This has to use 2 pages for the table headers in case a
556 * header spans a page boundary.
557 *
558 * XXX: We don't ensure the table fits in the available address space
559 * in the crashdump map.
560 */
561
562/*
563 * Map some memory using the crashdump map.  'offset' is an offset in
564 * pages into the crashdump map to use for the start of the mapping.
565 */
566static void *
567table_map(vm_paddr_t pa, int offset, vm_offset_t length)
568{
569	vm_offset_t va, off;
570	void *data;
571
572	off = pa & PAGE_MASK;
573	length = roundup(length + off, PAGE_SIZE);
574	pa = pa & PG_FRAME;
575	va = (vm_offset_t)pmap_kenter_temporary(pa, offset) +
576	    (offset * PAGE_SIZE);
577	data = (void *)(va + off);
578	length -= PAGE_SIZE;
579	while (length > 0) {
580		va += PAGE_SIZE;
581		pa += PAGE_SIZE;
582		length -= PAGE_SIZE;
583		pmap_kenter(va, pa);
584		invlpg(va);
585	}
586	return (data);
587}
588
589/* Unmap memory previously mapped with table_map(). */
590static void
591table_unmap(void *data, vm_offset_t length)
592{
593	vm_offset_t va, off;
594
595	va = (vm_offset_t)data;
596	off = va & PAGE_MASK;
597	length = roundup(length + off, PAGE_SIZE);
598	va &= ~PAGE_MASK;
599	while (length > 0) {
600		pmap_kremove(va);
601		invlpg(va);
602		va += PAGE_SIZE;
603		length -= PAGE_SIZE;
604	}
605}
606
607/*
608 * Map a table at a given offset into the crashdump map.  It first
609 * maps the header to determine the table length and then maps the
610 * entire table.
611 */
612static void *
613map_table(vm_paddr_t pa, int offset, const char *sig)
614{
615	ACPI_TABLE_HEADER *header;
616	vm_offset_t length;
617	void *table;
618
619	header = table_map(pa, offset, sizeof(ACPI_TABLE_HEADER));
620	if (strncmp(header->Signature, sig, ACPI_NAME_SIZE) != 0) {
621		table_unmap(header, sizeof(ACPI_TABLE_HEADER));
622		return (NULL);
623	}
624	length = header->Length;
625	table_unmap(header, sizeof(ACPI_TABLE_HEADER));
626	table = table_map(pa, offset, length);
627	if (ACPI_FAILURE(AcpiTbChecksum(table, length))) {
628		if (bootverbose)
629			printf("ACPI: Failed checksum for table %s\n", sig);
630		table_unmap(table, length);
631		return (NULL);
632	}
633	return (table);
634}
635
636/*
637 * See if a given ACPI table is the requested table.  Returns the
638 * length of the able if it matches or zero on failure.
639 */
640static int
641probe_table(vm_paddr_t address, const char *sig)
642{
643	ACPI_TABLE_HEADER *table;
644
645	table = table_map(address, 0, sizeof(ACPI_TABLE_HEADER));
646	if (table == NULL) {
647		if (bootverbose)
648			printf("ACPI: Failed to map table at 0x%jx\n",
649			    (uintmax_t)address);
650		return (0);
651	}
652	if (bootverbose)
653		printf("Table '%.4s' at 0x%jx\n", table->Signature,
654		    (uintmax_t)address);
655
656	if (strncmp(table->Signature, sig, ACPI_NAME_SIZE) != 0) {
657		table_unmap(table, sizeof(ACPI_TABLE_HEADER));
658		return (0);
659	}
660	table_unmap(table, sizeof(ACPI_TABLE_HEADER));
661	return (1);
662}
663
664/*
665 * Try to map a table at a given physical address previously returned
666 * by acpi_find_table().
667 */
668void *
669acpi_map_table(vm_paddr_t pa, const char *sig)
670{
671
672	return (map_table(pa, 0, sig));
673}
674
675/* Unmap a table previously mapped via acpi_map_table(). */
676void
677acpi_unmap_table(void *table)
678{
679	ACPI_TABLE_HEADER *header;
680
681	header = (ACPI_TABLE_HEADER *)table;
682	table_unmap(table, header->Length);
683}
684
685/*
686 * Return the physical address of the requested table or zero if one
687 * is not found.
688 */
689vm_paddr_t
690acpi_find_table(const char *sig)
691{
692	ACPI_PHYSICAL_ADDRESS rsdp_ptr;
693	ACPI_TABLE_RSDP *rsdp;
694	ACPI_TABLE_RSDT *rsdt;
695	ACPI_TABLE_XSDT *xsdt;
696	ACPI_TABLE_HEADER *table;
697	vm_paddr_t addr;
698	int i, count;
699
700	if (resource_disabled("acpi", 0))
701		return (0);
702
703	/*
704	 * Map in the RSDP.  Since ACPI uses AcpiOsMapMemory() which in turn
705	 * calls pmap_mapbios() to find the RSDP, we assume that we can use
706	 * pmap_mapbios() to map the RSDP.
707	 */
708	if ((rsdp_ptr = AcpiOsGetRootPointer()) == 0)
709		return (0);
710	rsdp = pmap_mapbios(rsdp_ptr, sizeof(ACPI_TABLE_RSDP));
711	if (rsdp == NULL) {
712		if (bootverbose)
713			printf("ACPI: Failed to map RSDP\n");
714		return (0);
715	}
716
717	/*
718	 * For ACPI >= 2.0, use the XSDT if it is available.
719	 * Otherwise, use the RSDT.  We map the XSDT or RSDT at page 2
720	 * in the crashdump area.  Pages 0 and 1 are used to map in the
721	 * headers of candidate ACPI tables.
722	 */
723	addr = 0;
724	if (rsdp->Revision >= 2 && rsdp->XsdtPhysicalAddress != 0) {
725		/*
726		 * AcpiOsGetRootPointer only verifies the checksum for
727		 * the version 1.0 portion of the RSDP.  Version 2.0 has
728		 * an additional checksum that we verify first.
729		 */
730		if (AcpiTbChecksum((UINT8 *)rsdp, ACPI_RSDP_XCHECKSUM_LENGTH)) {
731			if (bootverbose)
732				printf("ACPI: RSDP failed extended checksum\n");
733			return (0);
734		}
735		xsdt = map_table(rsdp->XsdtPhysicalAddress, 2, ACPI_SIG_XSDT);
736		if (xsdt == NULL) {
737			if (bootverbose)
738				printf("ACPI: Failed to map XSDT\n");
739			return (0);
740		}
741		count = (xsdt->Header.Length - sizeof(ACPI_TABLE_HEADER)) /
742		    sizeof(UINT64);
743		for (i = 0; i < count; i++)
744			if (probe_table(xsdt->TableOffsetEntry[i], sig)) {
745				addr = xsdt->TableOffsetEntry[i];
746				break;
747			}
748		acpi_unmap_table(xsdt);
749	} else {
750		rsdt = map_table(rsdp->RsdtPhysicalAddress, 2, ACPI_SIG_RSDT);
751		if (rsdt == NULL) {
752			if (bootverbose)
753				printf("ACPI: Failed to map RSDT\n");
754			return (0);
755		}
756		count = (rsdt->Header.Length - sizeof(ACPI_TABLE_HEADER)) /
757		    sizeof(UINT32);
758		for (i = 0; i < count; i++)
759			if (probe_table(rsdt->TableOffsetEntry[i], sig)) {
760				addr = rsdt->TableOffsetEntry[i];
761				break;
762			}
763		acpi_unmap_table(rsdt);
764	}
765	pmap_unmapbios((vm_offset_t)rsdp, sizeof(ACPI_TABLE_RSDP));
766	if (addr == 0) {
767		if (bootverbose)
768			printf("ACPI: No %s table found\n", sig);
769		return (0);
770	}
771	if (bootverbose)
772		printf("%s: Found table at 0x%jx\n", sig, (uintmax_t)addr);
773
774	/*
775	 * Verify that we can map the full table and that its checksum is
776	 * correct, etc.
777	 */
778	table = map_table(addr, 0, sig);
779	if (table == NULL)
780		return (0);
781	acpi_unmap_table(table);
782
783	return (addr);
784}
785
786/*
787 * ACPI nexus(4) driver.
788 */
789static int
790nexus_acpi_probe(device_t dev)
791{
792	int error;
793
794	error = acpi_identify();
795	if (error)
796		return (error);
797
798	return (BUS_PROBE_DEFAULT);
799}
800
801static int
802nexus_acpi_attach(device_t dev)
803{
804
805	nexus_init_resources();
806	bus_generic_probe(dev);
807	if (BUS_ADD_CHILD(dev, 10, "acpi", 0) == NULL)
808		panic("failed to add acpi0 device");
809
810	return (bus_generic_attach(dev));
811}
812
813static device_method_t nexus_acpi_methods[] = {
814	/* Device interface */
815	DEVMETHOD(device_probe,		nexus_acpi_probe),
816	DEVMETHOD(device_attach,	nexus_acpi_attach),
817
818	{ 0, 0 }
819};
820
821DEFINE_CLASS_1(nexus, nexus_acpi_driver, nexus_acpi_methods, 1, nexus_driver);
822static devclass_t nexus_devclass;
823
824DRIVER_MODULE(nexus_acpi, root, nexus_acpi_driver, nexus_devclass, 0, 0);
825