xref: /freebsd/sys/x86/isa/atrtc.c (revision 2ff63af9b88c7413b7d71715b5532625752a248e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2008 Poul-Henning Kamp
5  * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include "opt_acpi.h"
34 #include "opt_isa.h"
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 #include <sys/clock.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 #include <sys/kdb.h>
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/proc.h>
46 #include <sys/rman.h>
47 #include <sys/timeet.h>
48 
49 #include <isa/rtc.h>
50 #ifdef DEV_ISA
51 #include <isa/isareg.h>
52 #include <isa/isavar.h>
53 #endif
54 #include <machine/intr_machdep.h>
55 #include "clock_if.h"
56 #ifdef DEV_ACPI
57 #include <contrib/dev/acpica/include/acpi.h>
58 #include <contrib/dev/acpica/include/accommon.h>
59 #include <dev/acpica/acpivar.h>
60 #include <machine/md_var.h>
61 #endif
62 
63 /* tunable to detect a power loss of the rtc */
64 static bool atrtc_power_lost = false;
65 SYSCTL_BOOL(_machdep, OID_AUTO, atrtc_power_lost, CTLFLAG_RD, &atrtc_power_lost,
66     false, "RTC lost power on last power cycle (probably caused by an emtpy cmos battery)");
67 
68 /*
69  * atrtc_lock protects low-level access to individual hardware registers.
70  * atrtc_time_lock protects the entire sequence of accessing multiple registers
71  * to read or write the date and time.
72  */
73 static struct mtx atrtc_lock;
74 MTX_SYSINIT(atrtc_lock_init, &atrtc_lock, "atrtc", MTX_SPIN);
75 
76 /* Force RTC enabled/disabled. */
77 static int atrtc_enabled = -1;
78 TUNABLE_INT("hw.atrtc.enabled", &atrtc_enabled);
79 
80 struct mtx atrtc_time_lock;
81 MTX_SYSINIT(atrtc_time_lock_init, &atrtc_time_lock, "atrtc_time", MTX_DEF);
82 
83 int	atrtcclock_disable = 0;
84 
85 static	int	rtc_century = 0;
86 static	int	rtc_reg = -1;
87 static	u_char	rtc_statusa = RTCSA_DIVIDER | RTCSA_NOPROF;
88 static	u_char	rtc_statusb = RTCSB_24HR;
89 
90 #ifdef DEV_ACPI
91 #define	_COMPONENT	ACPI_TIMER
92 ACPI_MODULE_NAME("ATRTC")
93 #endif
94 
95 /*
96  * RTC support routines
97  */
98 
99 static inline u_char
100 rtcin_locked(int reg)
101 {
102 
103 	if (rtc_reg != reg) {
104 		inb(0x84);
105 		outb(IO_RTC, reg);
106 		rtc_reg = reg;
107 		inb(0x84);
108 	}
109 	return (inb(IO_RTC + 1));
110 }
111 
112 static inline void
113 rtcout_locked(int reg, u_char val)
114 {
115 
116 	if (rtc_reg != reg) {
117 		inb(0x84);
118 		outb(IO_RTC, reg);
119 		rtc_reg = reg;
120 		inb(0x84);
121 	}
122 	outb(IO_RTC + 1, val);
123 	inb(0x84);
124 }
125 
126 int
127 rtcin(int reg)
128 {
129 	u_char val;
130 
131 	mtx_lock_spin(&atrtc_lock);
132 	val = rtcin_locked(reg);
133 	mtx_unlock_spin(&atrtc_lock);
134 	return (val);
135 }
136 
137 void
138 writertc(int reg, u_char val)
139 {
140 
141 	mtx_lock_spin(&atrtc_lock);
142 	rtcout_locked(reg, val);
143 	mtx_unlock_spin(&atrtc_lock);
144 }
145 
146 static void
147 atrtc_start(void)
148 {
149 
150 	mtx_lock_spin(&atrtc_lock);
151 	rtcout_locked(RTC_STATUSA, rtc_statusa);
152 	rtcout_locked(RTC_STATUSB, RTCSB_24HR);
153 	mtx_unlock_spin(&atrtc_lock);
154 }
155 
156 static void
157 atrtc_rate(unsigned rate)
158 {
159 
160 	rtc_statusa = RTCSA_DIVIDER | rate;
161 	writertc(RTC_STATUSA, rtc_statusa);
162 }
163 
164 static void
165 atrtc_enable_intr(void)
166 {
167 
168 	rtc_statusb |= RTCSB_PINTR;
169 	mtx_lock_spin(&atrtc_lock);
170 	rtcout_locked(RTC_STATUSB, rtc_statusb);
171 	rtcin_locked(RTC_INTR);
172 	mtx_unlock_spin(&atrtc_lock);
173 }
174 
175 static void
176 atrtc_disable_intr(void)
177 {
178 
179 	rtc_statusb &= ~RTCSB_PINTR;
180 	mtx_lock_spin(&atrtc_lock);
181 	rtcout_locked(RTC_STATUSB, rtc_statusb);
182 	rtcin_locked(RTC_INTR);
183 	mtx_unlock_spin(&atrtc_lock);
184 }
185 
186 void
187 atrtc_restore(void)
188 {
189 
190 	/* Restore all of the RTC's "status" (actually, control) registers. */
191 	mtx_lock_spin(&atrtc_lock);
192 	rtcin_locked(RTC_STATUSA);	/* dummy to get rtc_reg set */
193 	rtcout_locked(RTC_STATUSB, RTCSB_24HR);
194 	rtcout_locked(RTC_STATUSA, rtc_statusa);
195 	rtcout_locked(RTC_STATUSB, rtc_statusb);
196 	rtcin_locked(RTC_INTR);
197 	mtx_unlock_spin(&atrtc_lock);
198 }
199 
200 /**********************************************************************
201  * RTC driver for subr_rtc
202  */
203 
204 struct atrtc_softc {
205 	int port_rid, intr_rid;
206 	struct resource *port_res;
207 	struct resource *intr_res;
208 	void *intr_handler;
209 	struct eventtimer et;
210 #ifdef DEV_ACPI
211 	ACPI_HANDLE acpi_handle;
212 #endif
213 };
214 
215 static int
216 rtc_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
217 {
218 
219 	atrtc_rate(max(fls(period + (period >> 1)) - 17, 1));
220 	atrtc_enable_intr();
221 	return (0);
222 }
223 
224 static int
225 rtc_stop(struct eventtimer *et)
226 {
227 
228 	atrtc_disable_intr();
229 	return (0);
230 }
231 
232 /*
233  * This routine receives statistical clock interrupts from the RTC.
234  * As explained above, these occur at 128 interrupts per second.
235  * When profiling, we receive interrupts at a rate of 1024 Hz.
236  *
237  * This does not actually add as much overhead as it sounds, because
238  * when the statistical clock is active, the hardclock driver no longer
239  * needs to keep (inaccurate) statistics on its own.  This decouples
240  * statistics gathering from scheduling interrupts.
241  *
242  * The RTC chip requires that we read status register C (RTC_INTR)
243  * to acknowledge an interrupt, before it will generate the next one.
244  * Under high interrupt load, rtcintr() can be indefinitely delayed and
245  * the clock can tick immediately after the read from RTC_INTR.  In this
246  * case, the mc146818A interrupt signal will not drop for long enough
247  * to register with the 8259 PIC.  If an interrupt is missed, the stat
248  * clock will halt, considerably degrading system performance.  This is
249  * why we use 'while' rather than a more straightforward 'if' below.
250  * Stat clock ticks can still be lost, causing minor loss of accuracy
251  * in the statistics, but the stat clock will no longer stop.
252  */
253 static int
254 rtc_intr(void *arg)
255 {
256 	struct atrtc_softc *sc = (struct atrtc_softc *)arg;
257 	int flag = 0;
258 
259 	while (rtcin(RTC_INTR) & RTCIR_PERIOD) {
260 		flag = 1;
261 		if (sc->et.et_active)
262 			sc->et.et_event_cb(&sc->et, sc->et.et_arg);
263 	}
264 	return(flag ? FILTER_HANDLED : FILTER_STRAY);
265 }
266 
267 #ifdef DEV_ACPI
268 /*
269  *  ACPI RTC CMOS address space handler
270  */
271 #define	ATRTC_LAST_REG	0x40
272 
273 static void
274 rtcin_region(int reg, void *buf, int len)
275 {
276 	u_char *ptr = buf;
277 
278 	/* Drop lock after each IO as intr and settime have greater priority */
279 	while (len-- > 0)
280 		*ptr++ = rtcin(reg++) & 0xff;
281 }
282 
283 static void
284 rtcout_region(int reg, const void *buf, int len)
285 {
286 	const u_char *ptr = buf;
287 
288 	while (len-- > 0)
289 		writertc(reg++, *ptr++);
290 }
291 
292 static bool
293 atrtc_check_cmos_access(bool is_read, ACPI_PHYSICAL_ADDRESS addr, UINT32 len)
294 {
295 
296 	/* Block address space wrapping on out-of-bound access */
297 	if (addr >= ATRTC_LAST_REG || addr + len > ATRTC_LAST_REG)
298 		return (false);
299 
300 	if (is_read) {
301 		/* Reading 0x0C will muck with interrupts */
302 		if (addr <= RTC_INTR && addr + len > RTC_INTR)
303 			return (false);
304 	} else {
305 		/*
306 		 * Allow single-byte writes to alarm registers and
307 		 * multi-byte writes to addr >= 0x30, else deny.
308 		 */
309 		if (!((len == 1 && (addr == RTC_SECALRM ||
310 				    addr == RTC_MINALRM ||
311 				    addr == RTC_HRSALRM)) ||
312 		      addr >= 0x30))
313 			return (false);
314 	}
315 	return (true);
316 }
317 
318 static ACPI_STATUS
319 atrtc_acpi_cmos_handler(UINT32 func, ACPI_PHYSICAL_ADDRESS addr,
320     UINT32 bitwidth, UINT64 *value, void *context, void *region_context)
321 {
322 	device_t dev = context;
323 	UINT32 bytewidth = howmany(bitwidth, 8);
324 	bool is_read = func == ACPI_READ;
325 
326 	/* ACPICA is very verbose on CMOS handler failures, so we, too */
327 #define	CMOS_HANDLER_ERR(fmt, ...) \
328 	device_printf(dev, "ACPI [SystemCMOS] handler: " fmt, ##__VA_ARGS__)
329 
330 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
331 
332 	if (value == NULL) {
333 		CMOS_HANDLER_ERR("NULL parameter\n");
334 		return (AE_BAD_PARAMETER);
335 	}
336 	if (bitwidth == 0 || (bitwidth & 0x07) != 0) {
337 		CMOS_HANDLER_ERR("Invalid bitwidth: %u\n", bitwidth);
338 		return (AE_BAD_PARAMETER);
339 	}
340 	if (!atrtc_check_cmos_access(is_read, addr, bytewidth)) {
341 		CMOS_HANDLER_ERR("%s access rejected: addr=%#04jx, len=%u\n",
342 		    is_read ? "Read" : "Write", (uintmax_t)addr, bytewidth);
343 		return (AE_BAD_PARAMETER);
344 	}
345 
346 	switch (func) {
347 	case ACPI_READ:
348 		rtcin_region(addr, value, bytewidth);
349 		break;
350 	case ACPI_WRITE:
351 		rtcout_region(addr, value, bytewidth);
352 		break;
353 	default:
354 		CMOS_HANDLER_ERR("Invalid function: %u\n", func);
355 		return (AE_BAD_PARAMETER);
356 	}
357 
358 	ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
359 	    "ACPI RTC CMOS %s access: addr=%#04x, len=%u, val=%*D\n",
360 	    is_read ? "read" : "write", (unsigned)addr, bytewidth,
361 	    bytewidth, value, " ");
362 
363 	return (AE_OK);
364 }
365 
366 static int
367 atrtc_reg_acpi_cmos_handler(device_t dev)
368 {
369 	struct atrtc_softc *sc = device_get_softc(dev);
370 
371 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
372 
373 	/* Don't handle address space events if driver is disabled. */
374 	if (acpi_disabled("atrtc"))
375 		return (ENXIO);
376 
377 	if (ACPI_FAILURE(AcpiGetHandle(ACPI_ROOT_OBJECT, "\\_SB_", &sc->acpi_handle))) {
378 		return (ENXIO);
379 	}
380 
381 	if (sc->acpi_handle == NULL ||
382 	    ACPI_FAILURE(AcpiInstallAddressSpaceHandler(sc->acpi_handle,
383 	      ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler, NULL, dev))) {
384 		sc->acpi_handle = NULL;
385 		device_printf(dev,
386 		    "Can't register ACPI CMOS address space handler\n");
387 		return (ENXIO);
388         }
389 
390         return (0);
391 }
392 
393 static int
394 atrtc_unreg_acpi_cmos_handler(device_t dev)
395 {
396 	struct atrtc_softc *sc = device_get_softc(dev);
397 
398 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
399 
400 	if (sc->acpi_handle != NULL)
401 		AcpiRemoveAddressSpaceHandler(sc->acpi_handle,
402 		    ACPI_ADR_SPACE_CMOS, atrtc_acpi_cmos_handler);
403 
404 	return (0);
405 }
406 #endif	/* DEV_ACPI */
407 
408 /*
409  * Attach to the ISA PnP descriptors for the timer and realtime clock.
410  */
411 static struct isa_pnp_id atrtc_ids[] = {
412 	{ 0x000bd041 /* PNP0B00 */, "AT realtime clock" },
413 	{ 0 }
414 };
415 
416 static bool
417 atrtc_acpi_disabled(void)
418 {
419 #ifdef DEV_ACPI
420 	uint16_t flags;
421 
422 	if (!acpi_get_fadt_bootflags(&flags))
423 		return (false);
424 	return ((flags & ACPI_FADT_NO_CMOS_RTC) != 0);
425 #else
426 	return (false);
427 #endif
428 }
429 
430 static int
431 rtc_acpi_century_get(void)
432 {
433 #ifdef DEV_ACPI
434 	ACPI_TABLE_FADT *fadt;
435 	vm_paddr_t physaddr;
436 	int century;
437 
438 	physaddr = acpi_find_table(ACPI_SIG_FADT);
439 	if (physaddr == 0)
440 		return (0);
441 
442 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
443 	if (fadt == NULL)
444 		return (0);
445 
446 	century = fadt->Century;
447 	acpi_unmap_table(fadt);
448 
449 	return (century);
450 #else
451 	return (0);
452 #endif
453 }
454 
455 static int
456 atrtc_probe(device_t dev)
457 {
458 	int result;
459 
460 	if ((atrtc_enabled == -1 && atrtc_acpi_disabled()) ||
461 	    (atrtc_enabled == 0))
462 		return (ENXIO);
463 
464 	result = ISA_PNP_PROBE(device_get_parent(dev), dev, atrtc_ids);
465 	/* ENOENT means no PnP-ID, device is hinted. */
466 	if (result == ENOENT) {
467 		device_set_desc(dev, "AT realtime clock");
468 		return (BUS_PROBE_LOW_PRIORITY);
469 	}
470 	rtc_century = rtc_acpi_century_get();
471 	return (result);
472 }
473 
474 static int
475 atrtc_attach(device_t dev)
476 {
477 	struct atrtc_softc *sc;
478 	rman_res_t s;
479 	int i;
480 
481 	sc = device_get_softc(dev);
482 	sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->port_rid,
483 	    IO_RTC, IO_RTC + 1, 2, RF_ACTIVE);
484 	if (sc->port_res == NULL)
485 		device_printf(dev, "Warning: Couldn't map I/O.\n");
486 	atrtc_start();
487 	clock_register(dev, 1000000);
488 	bzero(&sc->et, sizeof(struct eventtimer));
489 	if (!atrtcclock_disable &&
490 	    (resource_int_value(device_get_name(dev), device_get_unit(dev),
491 	     "clock", &i) != 0 || i != 0)) {
492 		sc->intr_rid = 0;
493 		while (bus_get_resource(dev, SYS_RES_IRQ, sc->intr_rid,
494 		    &s, NULL) == 0 && s != 8)
495 			sc->intr_rid++;
496 		sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
497 		    &sc->intr_rid, 8, 8, 1, RF_ACTIVE);
498 		if (sc->intr_res == NULL) {
499 			device_printf(dev, "Can't map interrupt.\n");
500 			return (0);
501 		} else if ((bus_setup_intr(dev, sc->intr_res, INTR_TYPE_CLK,
502 		    rtc_intr, NULL, sc, &sc->intr_handler))) {
503 			device_printf(dev, "Can't setup interrupt.\n");
504 			return (0);
505 		} else {
506 			/* Bind IRQ to BSP to avoid live migration. */
507 			bus_bind_intr(dev, sc->intr_res, 0);
508 		}
509 		sc->et.et_name = "RTC";
510 		sc->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_POW2DIV;
511 		sc->et.et_quality = 0;
512 		sc->et.et_frequency = 32768;
513 		sc->et.et_min_period = 0x00080000;
514 		sc->et.et_max_period = 0x80000000;
515 		sc->et.et_start = rtc_start;
516 		sc->et.et_stop = rtc_stop;
517 		sc->et.et_priv = dev;
518 		et_register(&sc->et);
519 	}
520 	return(0);
521 }
522 
523 static int
524 atrtc_isa_attach(device_t dev)
525 {
526 
527 	return (atrtc_attach(dev));
528 }
529 
530 #ifdef DEV_ACPI
531 static int
532 atrtc_acpi_attach(device_t dev)
533 {
534 	int ret;
535 
536 	ret = atrtc_attach(dev);
537 	if (ret)
538 		return (ret);
539 
540 	(void)atrtc_reg_acpi_cmos_handler(dev);
541 
542 	return (0);
543 }
544 
545 static int
546 atrtc_acpi_detach(device_t dev)
547 {
548 
549 	(void)atrtc_unreg_acpi_cmos_handler(dev);
550 	return (0);
551 }
552 #endif	/* DEV_ACPI */
553 
554 static int
555 atrtc_resume(device_t dev)
556 {
557 
558 	atrtc_restore();
559 	return(0);
560 }
561 
562 static int
563 atrtc_settime(device_t dev __unused, struct timespec *ts)
564 {
565 	struct bcd_clocktime bct;
566 
567 	clock_ts_to_bcd(ts, &bct, false);
568 	clock_dbgprint_bcd(dev, CLOCK_DBG_WRITE, &bct);
569 
570 	mtx_lock(&atrtc_time_lock);
571 	mtx_lock_spin(&atrtc_lock);
572 
573 	/* Disable RTC updates and interrupts.  */
574 	rtcout_locked(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR);
575 
576 	/* Write all the time registers. */
577 	rtcout_locked(RTC_SEC,   bct.sec);
578 	rtcout_locked(RTC_MIN,   bct.min);
579 	rtcout_locked(RTC_HRS,   bct.hour);
580 	rtcout_locked(RTC_WDAY,  bct.dow + 1);
581 	rtcout_locked(RTC_DAY,   bct.day);
582 	rtcout_locked(RTC_MONTH, bct.mon);
583 	rtcout_locked(RTC_YEAR,  bct.year & 0xff);
584 	if (rtc_century)
585 		rtcout_locked(rtc_century, bct.year >> 8);
586 
587 	/*
588 	 * Re-enable RTC updates and interrupts.
589 	 */
590 	rtcout_locked(RTC_STATUSB, rtc_statusb);
591 	rtcin_locked(RTC_INTR);
592 
593 	mtx_unlock_spin(&atrtc_lock);
594 	mtx_unlock(&atrtc_time_lock);
595 
596 	return (0);
597 }
598 
599 static int
600 atrtc_gettime(device_t dev, struct timespec *ts)
601 {
602 	struct bcd_clocktime bct;
603 
604 	/* Look if we have a RTC present and the time is valid */
605 	if (!(rtcin(RTC_STATUSD) & RTCSD_PWR)) {
606 		atrtc_power_lost = true;
607 		device_printf(dev, "WARNING: Battery failure indication\n");
608 		return (EINVAL);
609 	}
610 
611 	/*
612 	 * wait for time update to complete
613 	 * If RTCSA_TUP is zero, we have at least 244us before next update.
614 	 * This is fast enough on most hardware, but a refinement would be
615 	 * to make sure that no more than 240us pass after we start reading,
616 	 * and try again if so.
617 	 */
618 	mtx_lock(&atrtc_time_lock);
619 	while (rtcin(RTC_STATUSA) & RTCSA_TUP)
620 		continue;
621 	mtx_lock_spin(&atrtc_lock);
622 	bct.sec  = rtcin_locked(RTC_SEC);
623 	bct.min  = rtcin_locked(RTC_MIN);
624 	bct.hour = rtcin_locked(RTC_HRS);
625 	bct.day  = rtcin_locked(RTC_DAY);
626 	bct.mon  = rtcin_locked(RTC_MONTH);
627 	bct.year = rtcin_locked(RTC_YEAR);
628 	if (rtc_century)
629 		bct.year |= rtcin_locked(rtc_century) << 8;
630 	mtx_unlock_spin(&atrtc_lock);
631 	mtx_unlock(&atrtc_time_lock);
632 	/* dow is unused in timespec conversion and we have no nsec info. */
633 	bct.dow  = 0;
634 	bct.nsec = 0;
635 	clock_dbgprint_bcd(dev, CLOCK_DBG_READ, &bct);
636 	return (clock_bcd_to_ts(&bct, ts, false));
637 }
638 
639 static device_method_t atrtc_isa_methods[] = {
640 	/* Device interface */
641 	DEVMETHOD(device_probe,		atrtc_probe),
642 	DEVMETHOD(device_attach,	atrtc_isa_attach),
643 	DEVMETHOD(device_detach,	bus_generic_detach),
644 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
645 	DEVMETHOD(device_suspend,	bus_generic_suspend),
646 		/* XXX stop statclock? */
647 	DEVMETHOD(device_resume,	atrtc_resume),
648 
649 	/* clock interface */
650 	DEVMETHOD(clock_gettime,	atrtc_gettime),
651 	DEVMETHOD(clock_settime,	atrtc_settime),
652 	{ 0, 0 }
653 };
654 
655 static driver_t atrtc_isa_driver = {
656 	"atrtc",
657 	atrtc_isa_methods,
658 	sizeof(struct atrtc_softc),
659 };
660 
661 #ifdef DEV_ACPI
662 static device_method_t atrtc_acpi_methods[] = {
663 	/* Device interface */
664 	DEVMETHOD(device_probe,		atrtc_probe),
665 	DEVMETHOD(device_attach,	atrtc_acpi_attach),
666 	DEVMETHOD(device_detach,	atrtc_acpi_detach),
667 		/* XXX stop statclock? */
668 	DEVMETHOD(device_resume,	atrtc_resume),
669 
670 	/* clock interface */
671 	DEVMETHOD(clock_gettime,	atrtc_gettime),
672 	DEVMETHOD(clock_settime,	atrtc_settime),
673 	{ 0, 0 }
674 };
675 
676 static driver_t atrtc_acpi_driver = {
677 	"atrtc",
678 	atrtc_acpi_methods,
679 	sizeof(struct atrtc_softc),
680 };
681 #endif	/* DEV_ACPI */
682 
683 DRIVER_MODULE(atrtc, isa, atrtc_isa_driver, 0, 0);
684 #ifdef DEV_ACPI
685 DRIVER_MODULE(atrtc, acpi, atrtc_acpi_driver, 0, 0);
686 #endif
687 ISA_PNP_INFO(atrtc_ids);
688