apm.c revision 67882
1/*
2 * APM (Advanced Power Management) BIOS Device Driver
3 *
4 * Copyright (c) 1994 UKAI, Fumitoshi.
5 * Copyright (c) 1994-1995 by HOSOKAWA, Tatsumi <hosokawa@jp.FreeBSD.org>
6 * Copyright (c) 1996 Nate Williams <nate@FreeBSD.org>
7 * Copyright (c) 1997 Poul-Henning Kamp <phk@FreeBSD.org>
8 *
9 * This software may be used, modified, copied, and distributed, in
10 * both source and binary form provided that the above copyright and
11 * these terms are retained. Under no circumstances is the author
12 * responsible for the proper functioning of this software, nor does
13 * the author assume any responsibility for damages incurred with its
14 * use.
15 *
16 * Sep, 1994	Implemented on FreeBSD 1.1.5.1R (Toshiba AVS001WD)
17 *
18 * $FreeBSD: head/sys/i386/bios/apm.c 67882 2000-10-29 13:57:19Z phk $
19 */
20
21#include <sys/param.h>
22#include <sys/systm.h>
23#include <sys/eventhandler.h>
24#include <sys/conf.h>
25#include <sys/kernel.h>
26#include <sys/time.h>
27#include <sys/reboot.h>
28#include <sys/bus.h>
29#include <sys/select.h>
30#include <sys/poll.h>
31#include <sys/fcntl.h>
32#include <sys/uio.h>
33#include <sys/signalvar.h>
34#include <sys/sysctl.h>
35#include <machine/apm_bios.h>
36#include <machine/segments.h>
37#include <machine/clock.h>
38#include <vm/vm.h>
39#include <vm/vm_param.h>
40#include <vm/pmap.h>
41#include <sys/syslog.h>
42
43#include <machine/pc/bios.h>
44#include <machine/vm86.h>
45
46#include <i386/apm/apm.h>
47
48/* Used by the apm_saver screen saver module */
49int apm_display __P((int newstate));
50struct apm_softc apm_softc;
51
52static void apm_resume __P((void));
53static int apm_bioscall(void);
54static int apm_check_function_supported __P((u_int version, u_int func));
55
56static u_long	apm_version;
57
58int	apm_evindex;
59
60#define	SCFLAG_ONORMAL	0x0000001
61#define	SCFLAG_OCTL	0x0000002
62#define	SCFLAG_OPEN	(SCFLAG_ONORMAL|SCFLAG_OCTL)
63
64#define APMDEV(dev)	(minor(dev)&0x0f)
65#define APMDEV_NORMAL	0
66#define APMDEV_CTL	8
67
68static struct apmhook	*hook[NAPM_HOOK];		/* XXX */
69
70#define is_enabled(foo) ((foo) ? "enabled" : "disabled")
71
72/* Map version number to integer (keeps ordering of version numbers) */
73#define INTVERSION(major, minor)	((major)*100 + (minor))
74
75static struct callout_handle apm_timeout_ch =
76    CALLOUT_HANDLE_INITIALIZER(&apm_timeout_ch);
77
78static timeout_t apm_timeout;
79static d_open_t apmopen;
80static d_close_t apmclose;
81static d_write_t apmwrite;
82static d_ioctl_t apmioctl;
83static d_poll_t apmpoll;
84
85#define CDEV_MAJOR 39
86static struct cdevsw apm_cdevsw = {
87	/* open */	apmopen,
88	/* close */	apmclose,
89	/* read */	noread,
90	/* write */	apmwrite,
91	/* ioctl */	apmioctl,
92	/* poll */	apmpoll,
93	/* mmap */	nommap,
94	/* strategy */	nostrategy,
95	/* name */	"apm",
96	/* maj */	CDEV_MAJOR,
97	/* dump */	nodump,
98	/* psize */	nopsize,
99	/* flags */	0,
100	/* bmaj */	-1
101};
102
103static int apm_suspend_delay = 1;
104static int apm_standby_delay = 1;
105static int apm_debug = 0;
106
107#define APM_DPRINT(args...) do	{					\
108	if (apm_debug) {						\
109		printf(args);						\
110	}								\
111} while (0)
112
113SYSCTL_INT(_machdep, OID_AUTO, apm_suspend_delay, CTLFLAG_RW, &apm_suspend_delay, 1, "");
114SYSCTL_INT(_machdep, OID_AUTO, apm_standby_delay, CTLFLAG_RW, &apm_standby_delay, 1, "");
115SYSCTL_INT(_debug, OID_AUTO, apm_debug, CTLFLAG_RW, &apm_debug, 0, "");
116
117/*
118 * return  0 if the function successfull,
119 * return  1 if the function unsuccessfull,
120 * return -1 if the function unsupported.
121 */
122static int
123apm_bioscall(void)
124{
125	struct apm_softc *sc = &apm_softc;
126	int errno = 0;
127	u_int apm_func = sc->bios.r.eax & 0xff;
128
129	if (!apm_check_function_supported(sc->intversion, apm_func)) {
130		APM_DPRINT("apm_bioscall: function 0x%x is not supported in v%d.%d\n",
131		    apm_func, sc->majorversion, sc->minorversion);
132		return (-1);
133	}
134
135	sc->bios_busy = 1;
136	if (sc->connectmode == APM_PROT32CONNECT) {
137		set_bios_selectors(&sc->bios.seg,
138				   BIOSCODE_FLAG | BIOSDATA_FLAG);
139		errno = bios32(&sc->bios.r,
140			       sc->bios.entry, GSEL(GBIOSCODE32_SEL, SEL_KPL));
141	} else {
142		errno = bios16(&sc->bios, NULL);
143	}
144	sc->bios_busy = 0;
145	return (errno);
146}
147
148/* check whether APM function is supported (1)  or not (0). */
149static int
150apm_check_function_supported(u_int version, u_int func)
151{
152	/* except driver version */
153	if (func == APM_DRVVERSION) {
154		return (1);
155	}
156
157	switch (version) {
158	case INTVERSION(1, 0):
159		if (func > APM_GETPMEVENT) {
160			return (0); /* not supported */
161		}
162		break;
163	case INTVERSION(1, 1):
164		if (func > APM_ENGAGEDISENGAGEPM &&
165		    func < APM_OEMFUNC) {
166			return (0); /* not supported */
167		}
168		break;
169	case INTVERSION(1, 2):
170		break;
171	}
172
173	return (1); /* supported */
174}
175
176/* enable/disable power management */
177static int
178apm_enable_disable_pm(int enable)
179{
180	struct apm_softc *sc = &apm_softc;
181
182	sc->bios.r.eax = (APM_BIOS << 8) | APM_ENABLEDISABLEPM;
183
184	if (sc->intversion >= INTVERSION(1, 1))
185		sc->bios.r.ebx  = PMDV_ALLDEV;
186	else
187		sc->bios.r.ebx  = 0xffff;	/* APM version 1.0 only */
188	sc->bios.r.ecx  = enable;
189	sc->bios.r.edx = 0;
190	return (apm_bioscall());
191}
192
193/* register driver version (APM 1.1 or later) */
194static int
195apm_driver_version(int version)
196{
197	struct apm_softc *sc = &apm_softc;
198
199	sc->bios.r.eax = (APM_BIOS << 8) | APM_DRVVERSION;
200	sc->bios.r.ebx  = 0x0;
201	sc->bios.r.ecx  = version;
202	sc->bios.r.edx = 0;
203
204	if (apm_bioscall() == 0 && sc->bios.r.eax == version)
205		return (0);
206
207	/* Some old BIOSes don't return the connection version in %ax. */
208	if (sc->bios.r.eax == ((APM_BIOS << 8) | APM_DRVVERSION))
209		return (0);
210
211	return (1);
212}
213
214/* engage/disengage power management (APM 1.1 or later) */
215static int
216apm_engage_disengage_pm(int engage)
217{
218	struct apm_softc *sc = &apm_softc;
219
220	sc->bios.r.eax = (APM_BIOS << 8) | APM_ENGAGEDISENGAGEPM;
221	sc->bios.r.ebx = PMDV_ALLDEV;
222	sc->bios.r.ecx = engage;
223	sc->bios.r.edx = 0;
224	return (apm_bioscall());
225}
226
227/* get PM event */
228static u_int
229apm_getevent(void)
230{
231	struct apm_softc *sc = &apm_softc;
232
233	sc->bios.r.eax = (APM_BIOS << 8) | APM_GETPMEVENT;
234
235	sc->bios.r.ebx = 0;
236	sc->bios.r.ecx = 0;
237	sc->bios.r.edx = 0;
238	if (apm_bioscall())
239		return (PMEV_NOEVENT);
240	return (sc->bios.r.ebx & 0xffff);
241}
242
243/* suspend entire system */
244static int
245apm_suspend_system(int state)
246{
247	struct apm_softc *sc = &apm_softc;
248
249	sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
250	sc->bios.r.ebx = PMDV_ALLDEV;
251	sc->bios.r.ecx = state;
252	sc->bios.r.edx = 0;
253
254	if (apm_bioscall()) {
255 		printf("Entire system suspend failure: errcode = %d\n",
256		       0xff & (sc->bios.r.eax >> 8));
257 		return 1;
258 	}
259 	return 0;
260}
261
262/* Display control */
263/*
264 * Experimental implementation: My laptop machine can't handle this function
265 * If your laptop can control the display via APM, please inform me.
266 *                            HOSOKAWA, Tatsumi <hosokawa@jp.FreeBSD.org>
267 */
268int
269apm_display(int newstate)
270{
271	struct apm_softc *sc = &apm_softc;
272
273	sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
274	sc->bios.r.ebx = PMDV_DISP0;
275	sc->bios.r.ecx = newstate ? PMST_APMENABLED:PMST_SUSPEND;
276	sc->bios.r.edx = 0;
277	if (apm_bioscall() == 0) {
278		return 0;
279 	}
280
281	/* If failed, then try to blank all display devices instead. */
282	sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
283	sc->bios.r.ebx = PMDV_DISPALL;	/* all display devices */
284	sc->bios.r.ecx = newstate ? PMST_APMENABLED:PMST_SUSPEND;
285	sc->bios.r.edx = 0;
286	if (apm_bioscall() == 0) {
287		return 0;
288 	}
289 	printf("Display off failure: errcode = %d\n",
290	       0xff & (sc->bios.r.eax >> 8));
291 	return 1;
292}
293
294/*
295 * Turn off the entire system.
296 */
297static void
298apm_power_off(void *junk, int howto)
299{
300	struct apm_softc *sc = &apm_softc;
301
302	/* Not halting powering off, or not active */
303	if (!(howto & RB_POWEROFF) || !apm_softc.active)
304		return;
305	sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
306	sc->bios.r.ebx = PMDV_ALLDEV;
307	sc->bios.r.ecx = PMST_OFF;
308	sc->bios.r.edx = 0;
309	(void) apm_bioscall();
310}
311
312/* APM Battery low handler */
313static void
314apm_battery_low(void)
315{
316	printf("\007\007 * * * BATTERY IS LOW * * * \007\007");
317}
318
319/* APM hook manager */
320static struct apmhook *
321apm_add_hook(struct apmhook **list, struct apmhook *ah)
322{
323	int s;
324	struct apmhook *p, *prev;
325
326	APM_DPRINT("Add hook \"%s\"\n", ah->ah_name);
327
328	s = splhigh();
329	if (ah == NULL)
330		panic("illegal apm_hook!");
331	prev = NULL;
332	for (p = *list; p != NULL; prev = p, p = p->ah_next)
333		if (p->ah_order > ah->ah_order)
334			break;
335
336	if (prev == NULL) {
337		ah->ah_next = *list;
338		*list = ah;
339	} else {
340		ah->ah_next = prev->ah_next;
341		prev->ah_next = ah;
342	}
343	splx(s);
344	return ah;
345}
346
347static void
348apm_del_hook(struct apmhook **list, struct apmhook *ah)
349{
350	int s;
351	struct apmhook *p, *prev;
352
353	s = splhigh();
354	prev = NULL;
355	for (p = *list; p != NULL; prev = p, p = p->ah_next)
356		if (p == ah)
357			goto deleteit;
358	panic("Tried to delete unregistered apm_hook.");
359	goto nosuchnode;
360deleteit:
361	if (prev != NULL)
362		prev->ah_next = p->ah_next;
363	else
364		*list = p->ah_next;
365nosuchnode:
366	splx(s);
367}
368
369
370/* APM driver calls some functions automatically */
371static void
372apm_execute_hook(struct apmhook *list)
373{
374	struct apmhook *p;
375
376	for (p = list; p != NULL; p = p->ah_next) {
377		APM_DPRINT("Execute APM hook \"%s.\"\n", p->ah_name);
378		if ((*(p->ah_fun))(p->ah_arg))
379			printf("Warning: APM hook \"%s\" failed", p->ah_name);
380	}
381}
382
383
384/* establish an apm hook */
385struct apmhook *
386apm_hook_establish(int apmh, struct apmhook *ah)
387{
388	if (apmh < 0 || apmh >= NAPM_HOOK)
389		return NULL;
390
391	return apm_add_hook(&hook[apmh], ah);
392}
393
394/* disestablish an apm hook */
395void
396apm_hook_disestablish(int apmh, struct apmhook *ah)
397{
398	if (apmh < 0 || apmh >= NAPM_HOOK)
399		return;
400
401	apm_del_hook(&hook[apmh], ah);
402}
403
404static int apm_record_event __P((struct apm_softc *, u_int));
405static void apm_processevent(void);
406
407static u_int apm_op_inprog = 0;
408
409static void
410apm_do_suspend(void)
411{
412	struct apm_softc *sc = &apm_softc;
413	int error;
414
415	if (!sc)
416		return;
417
418	apm_op_inprog = 0;
419	sc->suspends = sc->suspend_countdown = 0;
420
421	if (sc->initialized) {
422		error = DEVICE_SUSPEND(root_bus);
423		if (error) {
424			DEVICE_RESUME(root_bus);
425		} else {
426			apm_execute_hook(hook[APM_HOOK_SUSPEND]);
427			if (apm_suspend_system(PMST_SUSPEND) == 0) {
428				sc->suspending = 1;
429				apm_processevent();
430			} else {
431				/* Failure, 'resume' the system again */
432				apm_execute_hook(hook[APM_HOOK_RESUME]);
433				DEVICE_RESUME(root_bus);
434			}
435		}
436	}
437}
438
439static void
440apm_do_standby(void)
441{
442	struct apm_softc *sc = &apm_softc;
443
444	if (!sc)
445		return;
446
447	apm_op_inprog = 0;
448	sc->standbys = sc->standby_countdown = 0;
449
450	if (sc->initialized) {
451		/*
452		 * As far as standby, we don't need to execute
453		 * all of suspend hooks.
454		 */
455		if (apm_suspend_system(PMST_STANDBY) == 0)
456			apm_processevent();
457	}
458}
459
460static void
461apm_lastreq_notify(void)
462{
463	struct apm_softc *sc = &apm_softc;
464
465	sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
466	sc->bios.r.ebx = PMDV_ALLDEV;
467	sc->bios.r.ecx = PMST_LASTREQNOTIFY;
468	sc->bios.r.edx = 0;
469	apm_bioscall();
470}
471
472static int
473apm_lastreq_rejected(void)
474{
475	struct apm_softc *sc = &apm_softc;
476
477	if (apm_op_inprog == 0) {
478		return 1;	/* no operation in progress */
479	}
480
481	sc->bios.r.eax = (APM_BIOS << 8) | APM_SETPWSTATE;
482	sc->bios.r.ebx = PMDV_ALLDEV;
483	sc->bios.r.ecx = PMST_LASTREQREJECT;
484	sc->bios.r.edx = 0;
485
486	if (apm_bioscall()) {
487		APM_DPRINT("apm_lastreq_rejected: failed\n");
488		return 1;
489	}
490	apm_op_inprog = 0;
491	return 0;
492}
493
494/*
495 * Public interface to the suspend/resume:
496 *
497 * Execute suspend and resume hook before and after sleep, respectively.
498 *
499 */
500
501void
502apm_suspend(int state)
503{
504	struct apm_softc *sc = &apm_softc;
505
506	if (!sc->initialized)
507		return;
508
509	switch (state) {
510	case PMST_SUSPEND:
511		if (sc->suspends)
512			return;
513		sc->suspends++;
514		sc->suspend_countdown = apm_suspend_delay;
515		break;
516	case PMST_STANDBY:
517		if (sc->standbys)
518			return;
519		sc->standbys++;
520		sc->standby_countdown = apm_standby_delay;
521		break;
522	default:
523		printf("apm_suspend: Unknown Suspend state 0x%x\n", state);
524		return;
525	}
526
527	apm_op_inprog++;
528	apm_lastreq_notify();
529}
530
531void
532apm_resume(void)
533{
534	struct apm_softc *sc = &apm_softc;
535
536	if (!sc)
537		return;
538
539	if (sc->suspending == 0)
540		return;
541
542	sc->suspending = 0;
543	if (sc->initialized) {
544		apm_execute_hook(hook[APM_HOOK_RESUME]);
545		DEVICE_RESUME(root_bus);
546	}
547}
548
549
550/* get power status per battery */
551static int
552apm_get_pwstatus(apm_pwstatus_t app)
553{
554	struct apm_softc *sc = &apm_softc;
555
556	if (app->ap_device != PMDV_ALLDEV &&
557	    (app->ap_device < PMDV_BATT0 || app->ap_device > PMDV_BATT_ALL))
558		return 1;
559
560	sc->bios.r.eax = (APM_BIOS << 8) | APM_GETPWSTATUS;
561	sc->bios.r.ebx = app->ap_device;
562	sc->bios.r.ecx = 0;
563	sc->bios.r.edx = 0xffff;	/* default to unknown battery time */
564
565	if (apm_bioscall())
566		return 1;
567
568	app->ap_acline    = (sc->bios.r.ebx >> 8) & 0xff;
569	app->ap_batt_stat = sc->bios.r.ebx & 0xff;
570	app->ap_batt_flag = (sc->bios.r.ecx >> 8) & 0xff;
571	app->ap_batt_life = sc->bios.r.ecx & 0xff;
572	sc->bios.r.edx &= 0xffff;
573	if (sc->bios.r.edx == 0xffff)	/* Time is unknown */
574		app->ap_batt_time = -1;
575	else if (sc->bios.r.edx & 0x8000)	/* Time is in minutes */
576		app->ap_batt_time = (sc->bios.r.edx & 0x7fff) * 60;
577	else				/* Time is in seconds */
578		app->ap_batt_time = sc->bios.r.edx;
579
580	return 0;
581}
582
583
584/* get APM information */
585static int
586apm_get_info(apm_info_t aip)
587{
588	struct apm_softc *sc = &apm_softc;
589	struct apm_pwstatus aps;
590
591	bzero(&aps, sizeof(aps));
592	aps.ap_device = PMDV_ALLDEV;
593	if (apm_get_pwstatus(&aps))
594		return 1;
595
596	aip->ai_infoversion = 1;
597	aip->ai_acline      = aps.ap_acline;
598	aip->ai_batt_stat   = aps.ap_batt_stat;
599	aip->ai_batt_life   = aps.ap_batt_life;
600	aip->ai_batt_time   = aps.ap_batt_time;
601	aip->ai_major       = (u_int)sc->majorversion;
602	aip->ai_minor       = (u_int)sc->minorversion;
603	aip->ai_status      = (u_int)sc->active;
604
605	sc->bios.r.eax = (APM_BIOS << 8) | APM_GETCAPABILITIES;
606	sc->bios.r.ebx = 0;
607	sc->bios.r.ecx = 0;
608	sc->bios.r.edx = 0;
609	if (apm_bioscall()) {
610		aip->ai_batteries = -1;	/* Unknown */
611		aip->ai_capabilities = 0xff00; /* Unknown, with no bits set */
612	} else {
613		aip->ai_batteries = sc->bios.r.ebx & 0xff;
614		aip->ai_capabilities = sc->bios.r.ecx & 0xf;
615	}
616
617	bzero(aip->ai_spare, sizeof aip->ai_spare);
618
619	return 0;
620}
621
622
623/* inform APM BIOS that CPU is idle */
624void
625apm_cpu_idle(void)
626{
627	struct apm_softc *sc = &apm_softc;
628
629	if (sc->active) {
630
631		sc->bios.r.eax = (APM_BIOS <<8) | APM_CPUIDLE;
632		sc->bios.r.edx = sc->bios.r.ecx = sc->bios.r.ebx = 0;
633		(void) apm_bioscall();
634	}
635	/*
636	 * Some APM implementation halts CPU in BIOS, whenever
637	 * "CPU-idle" function are invoked, but swtch() of
638	 * FreeBSD halts CPU, therefore, CPU is halted twice
639	 * in the sched loop. It makes the interrupt latency
640	 * terribly long and be able to cause a serious problem
641	 * in interrupt processing. We prevent it by removing
642	 * "hlt" operation from swtch() and managed it under
643	 * APM driver.
644	 */
645	if (!sc->active || sc->always_halt_cpu)
646		__asm("hlt");	/* wait for interrupt */
647}
648
649/* inform APM BIOS that CPU is busy */
650void
651apm_cpu_busy(void)
652{
653	struct apm_softc *sc = &apm_softc;
654
655	/*
656	 * The APM specification says this is only necessary if your BIOS
657	 * slows down the processor in the idle task, otherwise it's not
658	 * necessary.
659	 */
660	if (sc->slow_idle_cpu && sc->active) {
661
662		sc->bios.r.eax = (APM_BIOS <<8) | APM_CPUBUSY;
663		sc->bios.r.edx = sc->bios.r.ecx = sc->bios.r.ebx = 0;
664		apm_bioscall();
665	}
666}
667
668
669/*
670 * APM timeout routine:
671 *
672 * This routine is automatically called by timer once per second.
673 */
674
675static void
676apm_timeout(void *dummy)
677{
678	struct apm_softc *sc = &apm_softc;
679
680	if (apm_op_inprog)
681		apm_lastreq_notify();
682
683	if (sc->standbys && sc->standby_countdown-- <= 0)
684		apm_do_standby();
685
686	if (sc->suspends && sc->suspend_countdown-- <= 0)
687		apm_do_suspend();
688
689	if (!sc->bios_busy)
690		apm_processevent();
691
692	if (sc->active == 1)
693		/* Run slightly more oftan than 1 Hz */
694		apm_timeout_ch = timeout(apm_timeout, NULL, hz - 1 );
695}
696
697/* enable APM BIOS */
698static void
699apm_event_enable(void)
700{
701	struct apm_softc *sc = &apm_softc;
702
703	APM_DPRINT("called apm_event_enable()\n");
704	if (sc->initialized) {
705		sc->active = 1;
706		apm_timeout(sc);
707	}
708}
709
710/* disable APM BIOS */
711static void
712apm_event_disable(void)
713{
714	struct apm_softc *sc = &apm_softc;
715
716	APM_DPRINT("called apm_event_disable()\n");
717	if (sc->initialized) {
718		untimeout(apm_timeout, NULL, apm_timeout_ch);
719		sc->active = 0;
720	}
721}
722
723/* halt CPU in scheduling loop */
724static void
725apm_halt_cpu(void)
726{
727	struct apm_softc *sc = &apm_softc;
728
729	if (sc->initialized)
730		sc->always_halt_cpu = 1;
731}
732
733/* don't halt CPU in scheduling loop */
734static void
735apm_not_halt_cpu(void)
736{
737	struct apm_softc *sc = &apm_softc;
738
739	if (sc->initialized)
740		sc->always_halt_cpu = 0;
741}
742
743/* device driver definitions */
744
745/*
746 * Create "connection point"
747 */
748static void
749apm_identify(driver_t *driver, device_t parent)
750{
751	device_t child;
752
753	child = BUS_ADD_CHILD(parent, 0, "apm", 0);
754	if (child == NULL)
755		panic("apm_identify");
756}
757
758/*
759 * probe for APM BIOS
760 */
761static int
762apm_probe(device_t dev)
763{
764#define APM_KERNBASE	KERNBASE
765	struct vm86frame	vmf;
766	struct apm_softc	*sc = &apm_softc;
767	int			disabled, flags;
768
769	if (resource_int_value("apm", 0, "disabled", &disabled) == 0
770	    && disabled != 0)
771		return ENXIO;
772
773	device_set_desc(dev, "APM BIOS");
774
775	if ( device_get_unit(dev) > 0 ) {
776		printf("apm: Only one APM driver supported.\n");
777		return ENXIO;
778	}
779
780	if (resource_int_value("apm", 0, "flags", &flags) != 0)
781		flags = 0;
782
783	bzero(&vmf, sizeof(struct vm86frame));		/* safety */
784	bzero(&apm_softc, sizeof(apm_softc));
785	vmf.vmf_ah = APM_BIOS;
786	vmf.vmf_al = APM_INSTCHECK;
787	vmf.vmf_bx = 0;
788	if (vm86_intcall(APM_INT, &vmf))
789		return ENXIO;			/* APM not found */
790	if (vmf.vmf_bx != 0x504d) {
791		printf("apm: incorrect signature (0x%x)\n", vmf.vmf_bx);
792		return ENXIO;
793	}
794	if ((vmf.vmf_cx & (APM_32BIT_SUPPORT | APM_16BIT_SUPPORT)) == 0) {
795		printf("apm: protected mode connections are not supported\n");
796		return ENXIO;
797	}
798
799	apm_version = vmf.vmf_ax;
800	sc->slow_idle_cpu = ((vmf.vmf_cx & APM_CPUIDLE_SLOW) != 0);
801	sc->disabled = ((vmf.vmf_cx & APM_DISABLED) != 0);
802	sc->disengaged = ((vmf.vmf_cx & APM_DISENGAGED) != 0);
803
804	vmf.vmf_ah = APM_BIOS;
805	vmf.vmf_al = APM_DISCONNECT;
806	vmf.vmf_bx = 0;
807        vm86_intcall(APM_INT, &vmf);		/* disconnect, just in case */
808
809	if ((vmf.vmf_cx & APM_32BIT_SUPPORT) != 0) {
810		vmf.vmf_ah = APM_BIOS;
811		vmf.vmf_al = APM_PROT32CONNECT;
812		vmf.vmf_bx = 0;
813		if (vm86_intcall(APM_INT, &vmf)) {
814			printf("apm: 32-bit connection error.\n");
815			return (ENXIO);
816 		}
817		sc->bios.seg.code32.base = (vmf.vmf_ax << 4) + APM_KERNBASE;
818		sc->bios.seg.code32.limit = 0xffff;
819		sc->bios.seg.code16.base = (vmf.vmf_cx << 4) + APM_KERNBASE;
820		sc->bios.seg.code16.limit = 0xffff;
821		sc->bios.seg.data.base = (vmf.vmf_dx << 4) + APM_KERNBASE;
822		sc->bios.seg.data.limit = 0xffff;
823		sc->bios.entry = vmf.vmf_ebx;
824		sc->connectmode = APM_PROT32CONNECT;
825 	} else {
826		/* use 16-bit connection */
827		vmf.vmf_ah = APM_BIOS;
828		vmf.vmf_al = APM_PROT16CONNECT;
829		vmf.vmf_bx = 0;
830		if (vm86_intcall(APM_INT, &vmf)) {
831			printf("apm: 16-bit connection error.\n");
832			return (ENXIO);
833		}
834		sc->bios.seg.code16.base = (vmf.vmf_ax << 4) + APM_KERNBASE;
835		sc->bios.seg.code16.limit = 0xffff;
836		sc->bios.seg.data.base = (vmf.vmf_cx << 4) + APM_KERNBASE;
837		sc->bios.seg.data.limit = 0xffff;
838		sc->bios.entry = vmf.vmf_bx;
839		sc->connectmode = APM_PROT16CONNECT;
840	}
841	return(0);
842}
843
844
845/*
846 * return 0 if the user will notice and handle the event,
847 * return 1 if the kernel driver should do so.
848 */
849static int
850apm_record_event(struct apm_softc *sc, u_int event_type)
851{
852	struct apm_event_info *evp;
853
854	if ((sc->sc_flags & SCFLAG_OPEN) == 0)
855		return 1;		/* no user waiting */
856	if (sc->event_count == APM_NEVENTS)
857		return 1;			/* overflow */
858	if (sc->event_filter[event_type] == 0)
859		return 1;		/* not registered */
860	evp = &sc->event_list[sc->event_ptr];
861	sc->event_count++;
862	sc->event_ptr++;
863	sc->event_ptr %= APM_NEVENTS;
864	evp->type = event_type;
865	evp->index = ++apm_evindex;
866	selwakeup(&sc->sc_rsel);
867	return (sc->sc_flags & SCFLAG_OCTL) ? 0 : 1; /* user may handle */
868}
869
870/* Process APM event */
871static void
872apm_processevent(void)
873{
874	int apm_event;
875	struct apm_softc *sc = &apm_softc;
876
877#define OPMEV_DEBUGMESSAGE(symbol) case symbol:				\
878	APM_DPRINT("Received APM Event: " #symbol "\n");
879
880	do {
881		apm_event = apm_getevent();
882		switch (apm_event) {
883		    OPMEV_DEBUGMESSAGE(PMEV_STANDBYREQ);
884			if (apm_op_inprog == 0) {
885			    apm_op_inprog++;
886			    if (apm_record_event(sc, apm_event)) {
887				apm_suspend(PMST_STANDBY);
888			    }
889			}
890			break;
891		    OPMEV_DEBUGMESSAGE(PMEV_USERSTANDBYREQ);
892			if (apm_op_inprog == 0) {
893			    apm_op_inprog++;
894			    if (apm_record_event(sc, apm_event)) {
895				apm_suspend(PMST_STANDBY);
896			    }
897			}
898			break;
899		    OPMEV_DEBUGMESSAGE(PMEV_SUSPENDREQ);
900 			apm_lastreq_notify();
901			if (apm_op_inprog == 0) {
902			    apm_op_inprog++;
903			    if (apm_record_event(sc, apm_event)) {
904				apm_do_suspend();
905			    }
906			}
907			return; /* XXX skip the rest */
908		    OPMEV_DEBUGMESSAGE(PMEV_USERSUSPENDREQ);
909 			apm_lastreq_notify();
910			if (apm_op_inprog == 0) {
911			    apm_op_inprog++;
912			    if (apm_record_event(sc, apm_event)) {
913				apm_do_suspend();
914			    }
915			}
916			return; /* XXX skip the rest */
917		    OPMEV_DEBUGMESSAGE(PMEV_CRITSUSPEND);
918			apm_do_suspend();
919			break;
920		    OPMEV_DEBUGMESSAGE(PMEV_NORMRESUME);
921			apm_record_event(sc, apm_event);
922			apm_resume();
923			break;
924		    OPMEV_DEBUGMESSAGE(PMEV_CRITRESUME);
925			apm_record_event(sc, apm_event);
926			apm_resume();
927			break;
928		    OPMEV_DEBUGMESSAGE(PMEV_STANDBYRESUME);
929			apm_record_event(sc, apm_event);
930			break;
931		    OPMEV_DEBUGMESSAGE(PMEV_BATTERYLOW);
932			if (apm_record_event(sc, apm_event)) {
933			    apm_battery_low();
934			    apm_suspend(PMST_SUSPEND);
935			}
936			break;
937		    OPMEV_DEBUGMESSAGE(PMEV_POWERSTATECHANGE);
938			apm_record_event(sc, apm_event);
939			break;
940		    OPMEV_DEBUGMESSAGE(PMEV_UPDATETIME);
941			apm_record_event(sc, apm_event);
942			inittodr(0);	/* adjust time to RTC */
943			break;
944		    OPMEV_DEBUGMESSAGE(PMEV_CAPABILITIESCHANGE);
945			apm_record_event(sc, apm_event);
946			break;
947		    case PMEV_NOEVENT:
948			break;
949		    default:
950			printf("Unknown Original APM Event 0x%x\n", apm_event);
951			    break;
952		}
953	} while (apm_event != PMEV_NOEVENT);
954}
955
956/*
957 * Attach APM:
958 *
959 * Initialize APM driver
960 */
961
962static int
963apm_attach(device_t dev)
964{
965	struct apm_softc	*sc = &apm_softc;
966	int			flags;
967	int			drv_version;
968
969	if (resource_int_value("apm", 0, "flags", &flags) != 0)
970		flags = 0;
971
972	if (flags & 0x20)
973		statclock_disable = 1;
974
975	sc->initialized = 0;
976
977	/* Must be externally enabled */
978	sc->active = 0;
979
980	/* Always call HLT in idle loop */
981	sc->always_halt_cpu = 1;
982
983	getenv_int("debug.apm_debug", &apm_debug);
984
985	/* print bootstrap messages */
986	APM_DPRINT("apm: APM BIOS version %04lx\n",  apm_version);
987	APM_DPRINT("apm: Code16 0x%08x, Data 0x%08x\n",
988	    sc->bios.seg.code16.base, sc->bios.seg.data.base);
989	APM_DPRINT("apm: Code entry 0x%08x, Idling CPU %s, Management %s\n",
990	    sc->bios.entry, is_enabled(sc->slow_idle_cpu),
991	    is_enabled(!sc->disabled));
992	APM_DPRINT("apm: CS_limit=0x%x, DS_limit=0x%x\n",
993	    sc->bios.seg.code16.limit, sc->bios.seg.data.limit);
994
995	/*
996         * In one test, apm bios version was 1.02; an attempt to register
997         * a 1.04 driver resulted in a 1.00 connection!  Registering a
998         * 1.02 driver resulted in a 1.02 connection.
999         */
1000	drv_version = apm_version > 0x102 ? 0x102 : apm_version;
1001	for (; drv_version > 0x100; drv_version--)
1002		if (apm_driver_version(drv_version) == 0)
1003			break;
1004	sc->minorversion = ((drv_version & 0x00f0) >>  4) * 10 +
1005		((drv_version & 0x000f) >> 0);
1006	sc->majorversion = ((drv_version & 0xf000) >> 12) * 10 +
1007		((apm_version & 0x0f00) >> 8);
1008
1009	sc->intversion = INTVERSION(sc->majorversion, sc->minorversion);
1010
1011	if (sc->intversion >= INTVERSION(1, 1))
1012		APM_DPRINT("apm: Engaged control %s\n", is_enabled(!sc->disengaged));
1013	device_printf(dev, "found APM BIOS v%ld.%ld, connected at v%d.%d\n",
1014	       ((apm_version & 0xf000) >> 12) * 10 + ((apm_version & 0x0f00) >> 8),
1015	       ((apm_version & 0x00f0) >> 4) * 10 + ((apm_version & 0x000f) >> 0),
1016	       sc->majorversion, sc->minorversion);
1017
1018
1019	APM_DPRINT("apm: Slow Idling CPU %s\n", is_enabled(sc->slow_idle_cpu));
1020	/* enable power management */
1021	if (sc->disabled) {
1022		if (apm_enable_disable_pm(1)) {
1023			APM_DPRINT("apm: *Warning* enable function failed! [%x]\n",
1024			    (sc->bios.r.eax >> 8) & 0xff);
1025		}
1026	}
1027
1028	/* engage power managment (APM 1.1 or later) */
1029	if (sc->intversion >= INTVERSION(1, 1) && sc->disengaged) {
1030		if (apm_engage_disengage_pm(1)) {
1031			APM_DPRINT("apm: *Warning* engage function failed err=[%x]",
1032			    (sc->bios.r.eax >> 8) & 0xff);
1033			APM_DPRINT(" (Docked or using external power?).\n");
1034		}
1035	}
1036
1037	/* Power the system off using APM */
1038	EVENTHANDLER_REGISTER(shutdown_final, apm_power_off, NULL,
1039			      SHUTDOWN_PRI_LAST);
1040
1041	sc->initialized = 1;
1042	sc->suspending = 0;
1043
1044	make_dev(&apm_cdevsw, 0, 0, 5, 0660, "apm");
1045	make_dev(&apm_cdevsw, 8, 0, 5, 0660, "apmctl");
1046	return 0;
1047}
1048
1049static int
1050apmopen(dev_t dev, int flag, int fmt, struct proc *p)
1051{
1052	struct apm_softc *sc = &apm_softc;
1053	int ctl = APMDEV(dev);
1054
1055	if (!sc->initialized)
1056		return (ENXIO);
1057
1058	switch (ctl) {
1059	case APMDEV_CTL:
1060		if (!(flag & FWRITE))
1061			return EINVAL;
1062		if (sc->sc_flags & SCFLAG_OCTL)
1063			return EBUSY;
1064		sc->sc_flags |= SCFLAG_OCTL;
1065		bzero(sc->event_filter, sizeof sc->event_filter);
1066		break;
1067	case APMDEV_NORMAL:
1068		sc->sc_flags |= SCFLAG_ONORMAL;
1069		break;
1070	default:
1071		return ENXIO;
1072		break;
1073	}
1074	return 0;
1075}
1076
1077static int
1078apmclose(dev_t dev, int flag, int fmt, struct proc *p)
1079{
1080	struct apm_softc *sc = &apm_softc;
1081	int ctl = APMDEV(dev);
1082
1083	switch (ctl) {
1084	case APMDEV_CTL:
1085		apm_lastreq_rejected();
1086		sc->sc_flags &= ~SCFLAG_OCTL;
1087		bzero(sc->event_filter, sizeof sc->event_filter);
1088		break;
1089	case APMDEV_NORMAL:
1090		sc->sc_flags &= ~SCFLAG_ONORMAL;
1091		break;
1092	}
1093	if ((sc->sc_flags & SCFLAG_OPEN) == 0) {
1094		sc->event_count = 0;
1095		sc->event_ptr = 0;
1096	}
1097	return 0;
1098}
1099
1100static int
1101apmioctl(dev_t dev, u_long cmd, caddr_t addr, int flag, struct proc *p)
1102{
1103	struct apm_softc *sc = &apm_softc;
1104	struct apm_bios_arg *args;
1105	int error = 0;
1106	int ret;
1107	int newstate;
1108
1109	if (!sc->initialized)
1110		return (ENXIO);
1111	APM_DPRINT("APM ioctl: cmd = 0x%lx\n", cmd);
1112	switch (cmd) {
1113	case APMIO_SUSPEND:
1114		if (!(flag & FWRITE))
1115			return (EPERM);
1116		if (sc->active)
1117			apm_suspend(PMST_SUSPEND);
1118		else
1119			error = EINVAL;
1120		break;
1121
1122	case APMIO_STANDBY:
1123		if (!(flag & FWRITE))
1124			return (EPERM);
1125		if (sc->active)
1126			apm_suspend(PMST_STANDBY);
1127		else
1128			error = EINVAL;
1129		break;
1130
1131	case APMIO_GETINFO_OLD:
1132		{
1133			struct apm_info info;
1134			apm_info_old_t aiop;
1135
1136			if (apm_get_info(&info))
1137				error = ENXIO;
1138			aiop = (apm_info_old_t)addr;
1139			aiop->ai_major = info.ai_major;
1140			aiop->ai_minor = info.ai_minor;
1141			aiop->ai_acline = info.ai_acline;
1142			aiop->ai_batt_stat = info.ai_batt_stat;
1143			aiop->ai_batt_life = info.ai_batt_life;
1144			aiop->ai_status = info.ai_status;
1145		}
1146		break;
1147	case APMIO_GETINFO:
1148		if (apm_get_info((apm_info_t)addr))
1149			error = ENXIO;
1150		break;
1151	case APMIO_GETPWSTATUS:
1152		if (apm_get_pwstatus((apm_pwstatus_t)addr))
1153			error = ENXIO;
1154		break;
1155	case APMIO_ENABLE:
1156		if (!(flag & FWRITE))
1157			return (EPERM);
1158		apm_event_enable();
1159		break;
1160	case APMIO_DISABLE:
1161		if (!(flag & FWRITE))
1162			return (EPERM);
1163		apm_event_disable();
1164		break;
1165	case APMIO_HALTCPU:
1166		if (!(flag & FWRITE))
1167			return (EPERM);
1168		apm_halt_cpu();
1169		break;
1170	case APMIO_NOTHALTCPU:
1171		if (!(flag & FWRITE))
1172			return (EPERM);
1173		apm_not_halt_cpu();
1174		break;
1175	case APMIO_DISPLAY:
1176		if (!(flag & FWRITE))
1177			return (EPERM);
1178		newstate = *(int *)addr;
1179		if (apm_display(newstate))
1180			error = ENXIO;
1181		break;
1182	case APMIO_BIOS:
1183		if (!(flag & FWRITE))
1184			return (EPERM);
1185		/* XXX compatibility with the old interface */
1186		args = (struct apm_bios_arg *)addr;
1187		sc->bios.r.eax = args->eax;
1188		sc->bios.r.ebx = args->ebx;
1189		sc->bios.r.ecx = args->ecx;
1190		sc->bios.r.edx = args->edx;
1191		sc->bios.r.esi = args->esi;
1192		sc->bios.r.edi = args->edi;
1193		if ((ret = apm_bioscall())) {
1194			/*
1195			 * Return code 1 means bios call was unsuccessful.
1196			 * Error code is stored in %ah.
1197			 * Return code -1 means bios call was unsupported
1198			 * in the APM BIOS version.
1199			 */
1200			if (ret == -1) {
1201				error = EINVAL;
1202			}
1203		} else {
1204			/*
1205			 * Return code 0 means bios call was successful.
1206			 * We need only %al and can discard %ah.
1207			 */
1208			sc->bios.r.eax &= 0xff;
1209		}
1210		args->eax = sc->bios.r.eax;
1211		args->ebx = sc->bios.r.ebx;
1212		args->ecx = sc->bios.r.ecx;
1213		args->edx = sc->bios.r.edx;
1214		args->esi = sc->bios.r.esi;
1215		args->edi = sc->bios.r.edi;
1216		break;
1217	default:
1218		error = EINVAL;
1219		break;
1220	}
1221
1222	/* for /dev/apmctl */
1223	if (APMDEV(dev) == APMDEV_CTL) {
1224		struct apm_event_info *evp;
1225		int i;
1226
1227		error = 0;
1228		switch (cmd) {
1229		case APMIO_NEXTEVENT:
1230			if (!sc->event_count) {
1231				error = EAGAIN;
1232			} else {
1233				evp = (struct apm_event_info *)addr;
1234				i = sc->event_ptr + APM_NEVENTS - sc->event_count;
1235				i %= APM_NEVENTS;
1236				*evp = sc->event_list[i];
1237				sc->event_count--;
1238			}
1239			break;
1240		case APMIO_REJECTLASTREQ:
1241			if (apm_lastreq_rejected()) {
1242				error = EINVAL;
1243			}
1244			break;
1245		default:
1246			error = EINVAL;
1247			break;
1248		}
1249	}
1250
1251	return error;
1252}
1253
1254static int
1255apmwrite(dev_t dev, struct uio *uio, int ioflag)
1256{
1257	struct apm_softc *sc = &apm_softc;
1258	u_int event_type;
1259	int error;
1260	u_char enabled;
1261
1262	if (APMDEV(dev) != APMDEV_CTL)
1263		return(ENODEV);
1264	if (uio->uio_resid != sizeof(u_int))
1265		return(E2BIG);
1266
1267	if ((error = uiomove((caddr_t)&event_type, sizeof(u_int), uio)))
1268		return(error);
1269
1270	if (event_type < 0 || event_type >= APM_NPMEV)
1271		return(EINVAL);
1272
1273	if (sc->event_filter[event_type] == 0) {
1274		enabled = 1;
1275	} else {
1276		enabled = 0;
1277	}
1278	sc->event_filter[event_type] = enabled;
1279	APM_DPRINT("apmwrite: event 0x%x %s\n", event_type, is_enabled(enabled));
1280
1281	return uio->uio_resid;
1282}
1283
1284static int
1285apmpoll(dev_t dev, int events, struct proc *p)
1286{
1287	struct apm_softc *sc = &apm_softc;
1288	int revents = 0;
1289
1290	if (events & (POLLIN | POLLRDNORM)) {
1291		if (sc->event_count) {
1292			revents |= events & (POLLIN | POLLRDNORM);
1293		} else {
1294			selrecord(p, &sc->sc_rsel);
1295		}
1296	}
1297
1298	return (revents);
1299}
1300
1301static device_method_t apm_methods[] = {
1302	/* Device interface */
1303	DEVMETHOD(device_identify,	apm_identify),
1304	DEVMETHOD(device_probe,		apm_probe),
1305	DEVMETHOD(device_attach,	apm_attach),
1306
1307	{ 0, 0 }
1308};
1309
1310static driver_t apm_driver = {
1311	"apm",
1312	apm_methods,
1313	1,			/* no softc (XXX) */
1314};
1315
1316static devclass_t apm_devclass;
1317
1318DRIVER_MODULE(apm, nexus, apm_driver, apm_devclass, 0, 0);
1319