xref: /freebsd/sys/dev/acpica/acpi_hpet.c (revision 4c1a82cea504df7a79f5bd8f7d0a41cacccff16e)
1 /*-
2  * Copyright (c) 2005 Poul-Henning Kamp
3  * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include "opt_acpi.h"
32 
33 #if defined(__amd64__)
34 #define	DEV_APIC
35 #else
36 #include "opt_apic.h"
37 #endif
38 #include <sys/param.h>
39 #include <sys/conf.h>
40 #include <sys/bus.h>
41 #include <sys/kernel.h>
42 #include <sys/module.h>
43 #include <sys/proc.h>
44 #include <sys/rman.h>
45 #include <sys/mman.h>
46 #include <sys/time.h>
47 #include <sys/smp.h>
48 #include <sys/sysctl.h>
49 #include <sys/timeet.h>
50 #include <sys/timetc.h>
51 #include <sys/vdso.h>
52 
53 #include <contrib/dev/acpica/include/acpi.h>
54 #include <contrib/dev/acpica/include/accommon.h>
55 
56 #include <dev/acpica/acpivar.h>
57 #include <dev/acpica/acpi_hpet.h>
58 
59 #ifdef DEV_APIC
60 #include "pcib_if.h"
61 #endif
62 
63 #define HPET_VENDID_AMD		0x4353
64 #define HPET_VENDID_AMD2	0x1022
65 #define HPET_VENDID_INTEL	0x8086
66 #define HPET_VENDID_NVIDIA	0x10de
67 #define HPET_VENDID_SW		0x1166
68 
69 ACPI_SERIAL_DECL(hpet, "ACPI HPET support");
70 
71 static devclass_t hpet_devclass;
72 
73 /* ACPI CA debugging */
74 #define _COMPONENT	ACPI_TIMER
75 ACPI_MODULE_NAME("HPET")
76 
77 struct hpet_softc {
78 	device_t		dev;
79 	int			mem_rid;
80 	int			intr_rid;
81 	int			irq;
82 	int			useirq;
83 	int			legacy_route;
84 	int			per_cpu;
85 	uint32_t		allowed_irqs;
86 	struct resource		*mem_res;
87 	struct resource		*intr_res;
88 	void			*intr_handle;
89 	ACPI_HANDLE		handle;
90 	uint32_t		acpi_uid;
91 	uint64_t		freq;
92 	uint32_t		caps;
93 	struct timecounter	tc;
94 	struct hpet_timer {
95 		struct eventtimer	et;
96 		struct hpet_softc	*sc;
97 		int			num;
98 		int			mode;
99 #define	TIMER_STOPPED	0
100 #define	TIMER_PERIODIC	1
101 #define	TIMER_ONESHOT	2
102 		int			intr_rid;
103 		int			irq;
104 		int			pcpu_cpu;
105 		int			pcpu_misrouted;
106 		int			pcpu_master;
107 		int			pcpu_slaves[MAXCPU];
108 		struct resource		*intr_res;
109 		void			*intr_handle;
110 		uint32_t		caps;
111 		uint32_t		vectors;
112 		uint32_t		div;
113 		uint32_t		next;
114 		char			name[8];
115 	} 			t[32];
116 	int			num_timers;
117 	struct cdev		*pdev;
118 	int			mmap_allow;
119 	int			mmap_allow_write;
120 };
121 
122 static d_open_t hpet_open;
123 static d_mmap_t hpet_mmap;
124 
125 static struct cdevsw hpet_cdevsw = {
126 	.d_version =	D_VERSION,
127 	.d_name =	"hpet",
128 	.d_open =	hpet_open,
129 	.d_mmap =	hpet_mmap,
130 };
131 
132 static u_int hpet_get_timecount(struct timecounter *tc);
133 static void hpet_test(struct hpet_softc *sc);
134 
135 static char *hpet_ids[] = { "PNP0103", NULL };
136 
137 /* Knob to disable acpi_hpet device */
138 bool acpi_hpet_disabled = false;
139 
140 static u_int
141 hpet_get_timecount(struct timecounter *tc)
142 {
143 	struct hpet_softc *sc;
144 
145 	sc = tc->tc_priv;
146 	return (bus_read_4(sc->mem_res, HPET_MAIN_COUNTER));
147 }
148 
149 uint32_t
150 hpet_vdso_timehands(struct vdso_timehands *vdso_th, struct timecounter *tc)
151 {
152 	struct hpet_softc *sc;
153 
154 	sc = tc->tc_priv;
155 	vdso_th->th_algo = VDSO_TH_ALGO_X86_HPET;
156 	vdso_th->th_x86_shift = 0;
157 	vdso_th->th_x86_hpet_idx = device_get_unit(sc->dev);
158 	bzero(vdso_th->th_res, sizeof(vdso_th->th_res));
159 	return (sc->mmap_allow != 0);
160 }
161 
162 #ifdef COMPAT_FREEBSD32
163 uint32_t
164 hpet_vdso_timehands32(struct vdso_timehands32 *vdso_th32,
165     struct timecounter *tc)
166 {
167 	struct hpet_softc *sc;
168 
169 	sc = tc->tc_priv;
170 	vdso_th32->th_algo = VDSO_TH_ALGO_X86_HPET;
171 	vdso_th32->th_x86_shift = 0;
172 	vdso_th32->th_x86_hpet_idx = device_get_unit(sc->dev);
173 	bzero(vdso_th32->th_res, sizeof(vdso_th32->th_res));
174 	return (sc->mmap_allow != 0);
175 }
176 #endif
177 
178 static void
179 hpet_enable(struct hpet_softc *sc)
180 {
181 	uint32_t val;
182 
183 	val = bus_read_4(sc->mem_res, HPET_CONFIG);
184 	if (sc->legacy_route)
185 		val |= HPET_CNF_LEG_RT;
186 	else
187 		val &= ~HPET_CNF_LEG_RT;
188 	val |= HPET_CNF_ENABLE;
189 	bus_write_4(sc->mem_res, HPET_CONFIG, val);
190 }
191 
192 static void
193 hpet_disable(struct hpet_softc *sc)
194 {
195 	uint32_t val;
196 
197 	val = bus_read_4(sc->mem_res, HPET_CONFIG);
198 	val &= ~HPET_CNF_ENABLE;
199 	bus_write_4(sc->mem_res, HPET_CONFIG, val);
200 }
201 
202 static int
203 hpet_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
204 {
205 	struct hpet_timer *mt = (struct hpet_timer *)et->et_priv;
206 	struct hpet_timer *t;
207 	struct hpet_softc *sc = mt->sc;
208 	uint32_t fdiv, now;
209 
210 	t = (mt->pcpu_master < 0) ? mt : &sc->t[mt->pcpu_slaves[curcpu]];
211 	if (period != 0) {
212 		t->mode = TIMER_PERIODIC;
213 		t->div = (sc->freq * period) >> 32;
214 	} else {
215 		t->mode = TIMER_ONESHOT;
216 		t->div = 0;
217 	}
218 	if (first != 0)
219 		fdiv = (sc->freq * first) >> 32;
220 	else
221 		fdiv = t->div;
222 	if (t->irq < 0)
223 		bus_write_4(sc->mem_res, HPET_ISR, 1 << t->num);
224 	t->caps |= HPET_TCNF_INT_ENB;
225 	now = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
226 restart:
227 	t->next = now + fdiv;
228 	if (t->mode == TIMER_PERIODIC && (t->caps & HPET_TCAP_PER_INT)) {
229 		t->caps |= HPET_TCNF_TYPE;
230 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num),
231 		    t->caps | HPET_TCNF_VAL_SET);
232 		bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
233 		    t->next);
234 		bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
235 		    t->div);
236 	} else {
237 		t->caps &= ~HPET_TCNF_TYPE;
238 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num),
239 		    t->caps);
240 		bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
241 		    t->next);
242 	}
243 	now = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
244 	if ((int32_t)(now - t->next + HPET_MIN_CYCLES) >= 0) {
245 		fdiv *= 2;
246 		goto restart;
247 	}
248 	return (0);
249 }
250 
251 static int
252 hpet_stop(struct eventtimer *et)
253 {
254 	struct hpet_timer *mt = (struct hpet_timer *)et->et_priv;
255 	struct hpet_timer *t;
256 	struct hpet_softc *sc = mt->sc;
257 
258 	t = (mt->pcpu_master < 0) ? mt : &sc->t[mt->pcpu_slaves[curcpu]];
259 	t->mode = TIMER_STOPPED;
260 	t->caps &= ~(HPET_TCNF_INT_ENB | HPET_TCNF_TYPE);
261 	bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num), t->caps);
262 	return (0);
263 }
264 
265 static int
266 hpet_intr_single(void *arg)
267 {
268 	struct hpet_timer *t = (struct hpet_timer *)arg;
269 	struct hpet_timer *mt;
270 	struct hpet_softc *sc = t->sc;
271 	uint32_t now;
272 
273 	if (t->mode == TIMER_STOPPED)
274 		return (FILTER_STRAY);
275 	/* Check that per-CPU timer interrupt reached right CPU. */
276 	if (t->pcpu_cpu >= 0 && t->pcpu_cpu != curcpu) {
277 		if ((++t->pcpu_misrouted) % 32 == 0) {
278 			printf("HPET interrupt routed to the wrong CPU"
279 			    " (timer %d CPU %d -> %d)!\n",
280 			    t->num, t->pcpu_cpu, curcpu);
281 		}
282 
283 		/*
284 		 * Reload timer, hoping that next time may be more lucky
285 		 * (system will manage proper interrupt binding).
286 		 */
287 		if ((t->mode == TIMER_PERIODIC &&
288 		    (t->caps & HPET_TCAP_PER_INT) == 0) ||
289 		    t->mode == TIMER_ONESHOT) {
290 			t->next = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER) +
291 			    sc->freq / 8;
292 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
293 			    t->next);
294 		}
295 		return (FILTER_HANDLED);
296 	}
297 	if (t->mode == TIMER_PERIODIC &&
298 	    (t->caps & HPET_TCAP_PER_INT) == 0) {
299 		t->next += t->div;
300 		now = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
301 		if ((int32_t)((now + t->div / 2) - t->next) > 0)
302 			t->next = now + t->div / 2;
303 		bus_write_4(sc->mem_res,
304 		    HPET_TIMER_COMPARATOR(t->num), t->next);
305 	} else if (t->mode == TIMER_ONESHOT)
306 		t->mode = TIMER_STOPPED;
307 	mt = (t->pcpu_master < 0) ? t : &sc->t[t->pcpu_master];
308 	if (mt->et.et_active)
309 		mt->et.et_event_cb(&mt->et, mt->et.et_arg);
310 	return (FILTER_HANDLED);
311 }
312 
313 static int
314 hpet_intr(void *arg)
315 {
316 	struct hpet_softc *sc = (struct hpet_softc *)arg;
317 	int i;
318 	uint32_t val;
319 
320 	val = bus_read_4(sc->mem_res, HPET_ISR);
321 	if (val) {
322 		bus_write_4(sc->mem_res, HPET_ISR, val);
323 		val &= sc->useirq;
324 		for (i = 0; i < sc->num_timers; i++) {
325 			if ((val & (1 << i)) == 0)
326 				continue;
327 			hpet_intr_single(&sc->t[i]);
328 		}
329 		return (FILTER_HANDLED);
330 	}
331 	return (FILTER_STRAY);
332 }
333 
334 uint32_t
335 hpet_get_uid(device_t dev)
336 {
337 	struct hpet_softc *sc;
338 
339 	sc = device_get_softc(dev);
340 	return (sc->acpi_uid);
341 }
342 
343 static ACPI_STATUS
344 hpet_find(ACPI_HANDLE handle, UINT32 level, void *context,
345     void **status)
346 {
347 	char 		**ids;
348 	uint32_t	id = (uint32_t)(uintptr_t)context;
349 	uint32_t	uid = 0;
350 
351 	for (ids = hpet_ids; *ids != NULL; ids++) {
352 		if (acpi_MatchHid(handle, *ids))
353 		        break;
354 	}
355 	if (*ids == NULL)
356 		return (AE_OK);
357 	if (ACPI_FAILURE(acpi_GetInteger(handle, "_UID", &uid)) ||
358 	    id == uid)
359 		*status = acpi_get_device(handle);
360 	return (AE_OK);
361 }
362 
363 /*
364  * Find an existing IRQ resource that matches the requested IRQ range
365  * and return its RID.  If one is not found, use a new RID.
366  */
367 static int
368 hpet_find_irq_rid(device_t dev, u_long start, u_long end)
369 {
370 	rman_res_t irq;
371 	int error, rid;
372 
373 	for (rid = 0;; rid++) {
374 		error = bus_get_resource(dev, SYS_RES_IRQ, rid, &irq, NULL);
375 		if (error != 0 || (start <= irq && irq <= end))
376 			return (rid);
377 	}
378 }
379 
380 static int
381 hpet_open(struct cdev *cdev, int oflags, int devtype, struct thread *td)
382 {
383 	struct hpet_softc *sc;
384 
385 	sc = cdev->si_drv1;
386 	if (!sc->mmap_allow)
387 		return (EPERM);
388 	else
389 		return (0);
390 }
391 
392 static int
393 hpet_mmap(struct cdev *cdev, vm_ooffset_t offset, vm_paddr_t *paddr,
394     int nprot, vm_memattr_t *memattr)
395 {
396 	struct hpet_softc *sc;
397 
398 	sc = cdev->si_drv1;
399 	if (offset >= rman_get_size(sc->mem_res))
400 		return (EINVAL);
401 	if (!sc->mmap_allow_write && (nprot & PROT_WRITE))
402 		return (EPERM);
403 	*paddr = rman_get_start(sc->mem_res) + offset;
404 	*memattr = VM_MEMATTR_UNCACHEABLE;
405 
406 	return (0);
407 }
408 
409 /* Discover the HPET via the ACPI table of the same name. */
410 static void
411 hpet_identify(driver_t *driver, device_t parent)
412 {
413 	ACPI_TABLE_HPET *hpet;
414 	ACPI_STATUS	status;
415 	device_t	child;
416 	int		i;
417 
418 	/* Only one HPET device can be added. */
419 	if (devclass_get_device(hpet_devclass, 0))
420 		return;
421 	for (i = 1; ; i++) {
422 		/* Search for HPET table. */
423 		status = AcpiGetTable(ACPI_SIG_HPET, i, (ACPI_TABLE_HEADER **)&hpet);
424 		if (ACPI_FAILURE(status))
425 			return;
426 		/* Search for HPET device with same ID. */
427 		child = NULL;
428 		AcpiWalkNamespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
429 		    100, hpet_find, NULL, (void *)(uintptr_t)hpet->Sequence,
430 		    (void *)&child);
431 		/* If found - let it be probed in normal way. */
432 		if (child) {
433 			if (bus_get_resource(child, SYS_RES_MEMORY, 0,
434 			    NULL, NULL) != 0)
435 				bus_set_resource(child, SYS_RES_MEMORY, 0,
436 				    hpet->Address.Address, HPET_MEM_WIDTH);
437 			continue;
438 		}
439 		/* If not - create it from table info. */
440 		child = BUS_ADD_CHILD(parent, 2, "hpet", 0);
441 		if (child == NULL) {
442 			printf("%s: can't add child\n", __func__);
443 			continue;
444 		}
445 		bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address,
446 		    HPET_MEM_WIDTH);
447 	}
448 }
449 
450 static int
451 hpet_probe(device_t dev)
452 {
453 	int rv;
454 
455 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
456 	if (acpi_disabled("hpet") || acpi_hpet_disabled)
457 		return (ENXIO);
458 	if (acpi_get_handle(dev) != NULL)
459 		rv = ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids, NULL);
460 	else
461 		rv = 0;
462 	if (rv <= 0)
463 		device_set_desc(dev, "High Precision Event Timer");
464 	return (rv);
465 }
466 
467 static int
468 hpet_attach(device_t dev)
469 {
470 	struct hpet_softc *sc;
471 	struct hpet_timer *t;
472 	struct make_dev_args mda;
473 	int i, j, num_msi, num_timers, num_percpu_et, num_percpu_t, cur_cpu;
474 	int pcpu_master, error;
475 	static int maxhpetet = 0;
476 	uint32_t val, val2, cvectors, dvectors;
477 	uint16_t vendor, rev;
478 
479 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
480 
481 	sc = device_get_softc(dev);
482 	sc->dev = dev;
483 	sc->handle = acpi_get_handle(dev);
484 
485 	sc->mem_rid = 0;
486 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->mem_rid,
487 	    RF_ACTIVE);
488 	if (sc->mem_res == NULL)
489 		return (ENOMEM);
490 
491 	/* Validate that we can access the whole region. */
492 	if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH) {
493 		device_printf(dev, "memory region width %jd too small\n",
494 		    rman_get_size(sc->mem_res));
495 		bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
496 		return (ENXIO);
497 	}
498 
499 	/* Be sure timer is enabled. */
500 	hpet_enable(sc);
501 
502 	/* Read basic statistics about the timer. */
503 	val = bus_read_4(sc->mem_res, HPET_PERIOD);
504 	if (val == 0) {
505 		device_printf(dev, "invalid period\n");
506 		hpet_disable(sc);
507 		bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
508 		return (ENXIO);
509 	}
510 
511 	sc->freq = (1000000000000000LL + val / 2) / val;
512 	sc->caps = bus_read_4(sc->mem_res, HPET_CAPABILITIES);
513 	vendor = (sc->caps & HPET_CAP_VENDOR_ID) >> 16;
514 	rev = sc->caps & HPET_CAP_REV_ID;
515 	num_timers = 1 + ((sc->caps & HPET_CAP_NUM_TIM) >> 8);
516 	/*
517 	 * ATI/AMD violates IA-PC HPET (High Precision Event Timers)
518 	 * Specification and provides an off by one number
519 	 * of timers/comparators.
520 	 * Additionally, they use unregistered value in VENDOR_ID field.
521 	 */
522 	if (vendor == HPET_VENDID_AMD && rev < 0x10 && num_timers > 0)
523 		num_timers--;
524 	sc->num_timers = num_timers;
525 	if (bootverbose) {
526 		device_printf(dev,
527 		    "vendor 0x%x, rev 0x%x, %jdHz%s, %d timers,%s\n",
528 		    vendor, rev, sc->freq,
529 		    (sc->caps & HPET_CAP_COUNT_SIZE) ? " 64bit" : "",
530 		    num_timers,
531 		    (sc->caps & HPET_CAP_LEG_RT) ? " legacy route" : "");
532 	}
533 	for (i = 0; i < num_timers; i++) {
534 		t = &sc->t[i];
535 		t->sc = sc;
536 		t->num = i;
537 		t->mode = TIMER_STOPPED;
538 		t->intr_rid = -1;
539 		t->irq = -1;
540 		t->pcpu_cpu = -1;
541 		t->pcpu_misrouted = 0;
542 		t->pcpu_master = -1;
543 		t->caps = bus_read_4(sc->mem_res, HPET_TIMER_CAP_CNF(i));
544 		t->vectors = bus_read_4(sc->mem_res, HPET_TIMER_CAP_CNF(i) + 4);
545 		if (bootverbose) {
546 			device_printf(dev,
547 			    " t%d: irqs 0x%08x (%d)%s%s%s\n", i,
548 			    t->vectors, (t->caps & HPET_TCNF_INT_ROUTE) >> 9,
549 			    (t->caps & HPET_TCAP_FSB_INT_DEL) ? ", MSI" : "",
550 			    (t->caps & HPET_TCAP_SIZE) ? ", 64bit" : "",
551 			    (t->caps & HPET_TCAP_PER_INT) ? ", periodic" : "");
552 		}
553 	}
554 	if (testenv("debug.acpi.hpet_test"))
555 		hpet_test(sc);
556 	/*
557 	 * Don't attach if the timer never increments.  Since the spec
558 	 * requires it to be at least 10 MHz, it has to change in 1 us.
559 	 */
560 	val = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
561 	DELAY(1);
562 	val2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
563 	if (val == val2) {
564 		device_printf(dev, "HPET never increments, disabling\n");
565 		hpet_disable(sc);
566 		bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
567 		return (ENXIO);
568 	}
569 	/* Announce first HPET as timecounter. */
570 	if (device_get_unit(dev) == 0) {
571 		sc->tc.tc_get_timecount = hpet_get_timecount,
572 		sc->tc.tc_counter_mask = ~0u,
573 		sc->tc.tc_name = "HPET",
574 		sc->tc.tc_quality = 950,
575 		sc->tc.tc_frequency = sc->freq;
576 		sc->tc.tc_priv = sc;
577 		sc->tc.tc_fill_vdso_timehands = hpet_vdso_timehands;
578 #ifdef COMPAT_FREEBSD32
579 		sc->tc.tc_fill_vdso_timehands32 = hpet_vdso_timehands32;
580 #endif
581 		tc_init(&sc->tc);
582 	}
583 	/* If not disabled - setup and announce event timers. */
584 	if (resource_int_value(device_get_name(dev), device_get_unit(dev),
585 	     "clock", &i) == 0 && i == 0)
586 	        return (0);
587 
588 	/* Check whether we can and want legacy routing. */
589 	sc->legacy_route = 0;
590 	resource_int_value(device_get_name(dev), device_get_unit(dev),
591 	     "legacy_route", &sc->legacy_route);
592 	if ((sc->caps & HPET_CAP_LEG_RT) == 0)
593 		sc->legacy_route = 0;
594 	if (sc->legacy_route) {
595 		sc->t[0].vectors = 0;
596 		sc->t[1].vectors = 0;
597 	}
598 
599 	/* Check what IRQs we want use. */
600 	/* By default allow any PCI IRQs. */
601 	sc->allowed_irqs = 0xffff0000;
602 	/*
603 	 * HPETs in AMD chipsets before SB800 have problems with IRQs >= 16
604 	 * Lower are also not always working for different reasons.
605 	 * SB800 fixed it, but seems do not implements level triggering
606 	 * properly, that makes it very unreliable - it freezes after any
607 	 * interrupt loss. Avoid legacy IRQs for AMD.
608 	 */
609 	if (vendor == HPET_VENDID_AMD || vendor == HPET_VENDID_AMD2)
610 		sc->allowed_irqs = 0x00000000;
611 	/*
612 	 * NVidia MCP5x chipsets have number of unexplained interrupt
613 	 * problems. For some reason, using HPET interrupts breaks HDA sound.
614 	 */
615 	if (vendor == HPET_VENDID_NVIDIA && rev <= 0x01)
616 		sc->allowed_irqs = 0x00000000;
617 	/*
618 	 * ServerWorks HT1000 reported to have problems with IRQs >= 16.
619 	 * Lower IRQs are working, but allowed mask is not set correctly.
620 	 * Legacy_route mode works fine.
621 	 */
622 	if (vendor == HPET_VENDID_SW && rev <= 0x01)
623 		sc->allowed_irqs = 0x00000000;
624 	/*
625 	 * Neither QEMU nor VirtualBox report supported IRQs correctly.
626 	 * The only way to use HPET there is to specify IRQs manually
627 	 * and/or use legacy_route. Legacy_route mode works on both.
628 	 */
629 	if (vm_guest)
630 		sc->allowed_irqs = 0x00000000;
631 	/* Let user override. */
632 	resource_int_value(device_get_name(dev), device_get_unit(dev),
633 	     "allowed_irqs", &sc->allowed_irqs);
634 
635 	/* Get how much per-CPU timers we should try to provide. */
636 	sc->per_cpu = 1;
637 	resource_int_value(device_get_name(dev), device_get_unit(dev),
638 	     "per_cpu", &sc->per_cpu);
639 
640 	num_msi = 0;
641 	sc->useirq = 0;
642 	/* Find IRQ vectors for all timers. */
643 	cvectors = sc->allowed_irqs & 0xffff0000;
644 	dvectors = sc->allowed_irqs & 0x0000ffff;
645 	if (sc->legacy_route)
646 		dvectors &= 0x0000fefe;
647 	for (i = 0; i < num_timers; i++) {
648 		t = &sc->t[i];
649 		if (sc->legacy_route && i < 2)
650 			t->irq = (i == 0) ? 0 : 8;
651 #ifdef DEV_APIC
652 		else if (t->caps & HPET_TCAP_FSB_INT_DEL) {
653 			if ((j = PCIB_ALLOC_MSIX(
654 			    device_get_parent(device_get_parent(dev)), dev,
655 			    &t->irq))) {
656 				device_printf(dev,
657 				    "Can't allocate interrupt for t%d: %d\n",
658 				    i, j);
659 			}
660 		}
661 #endif
662 		else if (dvectors & t->vectors) {
663 			t->irq = ffs(dvectors & t->vectors) - 1;
664 			dvectors &= ~(1 << t->irq);
665 		}
666 		if (t->irq >= 0) {
667 			t->intr_rid = hpet_find_irq_rid(dev, t->irq, t->irq);
668 			t->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
669 			    &t->intr_rid, t->irq, t->irq, 1, RF_ACTIVE);
670 			if (t->intr_res == NULL) {
671 				t->irq = -1;
672 				device_printf(dev,
673 				    "Can't map interrupt for t%d.\n", i);
674 			} else if (bus_setup_intr(dev, t->intr_res,
675 			    INTR_TYPE_CLK, hpet_intr_single, NULL, t,
676 			    &t->intr_handle) != 0) {
677 				t->irq = -1;
678 				device_printf(dev,
679 				    "Can't setup interrupt for t%d.\n", i);
680 			} else {
681 				bus_describe_intr(dev, t->intr_res,
682 				    t->intr_handle, "t%d", i);
683 				num_msi++;
684 			}
685 		}
686 		if (t->irq < 0 && (cvectors & t->vectors) != 0) {
687 			cvectors &= t->vectors;
688 			sc->useirq |= (1 << i);
689 		}
690 	}
691 	if (sc->legacy_route && sc->t[0].irq < 0 && sc->t[1].irq < 0)
692 		sc->legacy_route = 0;
693 	if (sc->legacy_route)
694 		hpet_enable(sc);
695 	/* Group timers for per-CPU operation. */
696 	num_percpu_et = min(num_msi / mp_ncpus, sc->per_cpu);
697 	num_percpu_t = num_percpu_et * mp_ncpus;
698 	pcpu_master = 0;
699 	cur_cpu = CPU_FIRST();
700 	for (i = 0; i < num_timers; i++) {
701 		t = &sc->t[i];
702 		if (t->irq >= 0 && num_percpu_t > 0) {
703 			if (cur_cpu == CPU_FIRST())
704 				pcpu_master = i;
705 			t->pcpu_cpu = cur_cpu;
706 			t->pcpu_master = pcpu_master;
707 			sc->t[pcpu_master].
708 			    pcpu_slaves[cur_cpu] = i;
709 			bus_bind_intr(dev, t->intr_res, cur_cpu);
710 			cur_cpu = CPU_NEXT(cur_cpu);
711 			num_percpu_t--;
712 		} else if (t->irq >= 0)
713 			bus_bind_intr(dev, t->intr_res, CPU_FIRST());
714 	}
715 	bus_write_4(sc->mem_res, HPET_ISR, 0xffffffff);
716 	sc->irq = -1;
717 	/* If at least one timer needs legacy IRQ - set it up. */
718 	if (sc->useirq) {
719 		j = i = fls(cvectors) - 1;
720 		while (j > 0 && (cvectors & (1 << (j - 1))) != 0)
721 			j--;
722 		sc->intr_rid = hpet_find_irq_rid(dev, j, i);
723 		sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
724 		    &sc->intr_rid, j, i, 1, RF_SHAREABLE | RF_ACTIVE);
725 		if (sc->intr_res == NULL)
726 			device_printf(dev, "Can't map interrupt.\n");
727 		else if (bus_setup_intr(dev, sc->intr_res, INTR_TYPE_CLK,
728 		    hpet_intr, NULL, sc, &sc->intr_handle) != 0) {
729 			device_printf(dev, "Can't setup interrupt.\n");
730 		} else {
731 			sc->irq = rman_get_start(sc->intr_res);
732 			/* Bind IRQ to BSP to avoid live migration. */
733 			bus_bind_intr(dev, sc->intr_res, CPU_FIRST());
734 		}
735 	}
736 	/* Program and announce event timers. */
737 	for (i = 0; i < num_timers; i++) {
738 		t = &sc->t[i];
739 		t->caps &= ~(HPET_TCNF_FSB_EN | HPET_TCNF_INT_ROUTE);
740 		t->caps &= ~(HPET_TCNF_VAL_SET | HPET_TCNF_INT_ENB);
741 		t->caps &= ~(HPET_TCNF_INT_TYPE);
742 		t->caps |= HPET_TCNF_32MODE;
743 		if (t->irq >= 0 && sc->legacy_route && i < 2) {
744 			/* Legacy route doesn't need more configuration. */
745 		} else
746 #ifdef DEV_APIC
747 		if ((t->caps & HPET_TCAP_FSB_INT_DEL) && t->irq >= 0) {
748 			uint64_t addr;
749 			uint32_t data;
750 
751 			if (PCIB_MAP_MSI(
752 			    device_get_parent(device_get_parent(dev)), dev,
753 			    t->irq, &addr, &data) == 0) {
754 				bus_write_4(sc->mem_res,
755 				    HPET_TIMER_FSB_ADDR(i), addr);
756 				bus_write_4(sc->mem_res,
757 				    HPET_TIMER_FSB_VAL(i), data);
758 				t->caps |= HPET_TCNF_FSB_EN;
759 			} else
760 				t->irq = -2;
761 		} else
762 #endif
763 		if (t->irq >= 0)
764 			t->caps |= (t->irq << 9);
765 		else if (sc->irq >= 0 && (t->vectors & (1 << sc->irq)))
766 			t->caps |= (sc->irq << 9) | HPET_TCNF_INT_TYPE;
767 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(i), t->caps);
768 		/* Skip event timers without set up IRQ. */
769 		if (t->irq < 0 &&
770 		    (sc->irq < 0 || (t->vectors & (1 << sc->irq)) == 0))
771 			continue;
772 		/* Announce the reset. */
773 		if (maxhpetet == 0)
774 			t->et.et_name = "HPET";
775 		else {
776 			sprintf(t->name, "HPET%d", maxhpetet);
777 			t->et.et_name = t->name;
778 		}
779 		t->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT;
780 		t->et.et_quality = 450;
781 		if (t->pcpu_master >= 0) {
782 			t->et.et_flags |= ET_FLAGS_PERCPU;
783 			t->et.et_quality += 100;
784 		} else if (mp_ncpus >= 8)
785 			t->et.et_quality -= 100;
786 		if ((t->caps & HPET_TCAP_PER_INT) == 0)
787 			t->et.et_quality -= 10;
788 		t->et.et_frequency = sc->freq;
789 		t->et.et_min_period =
790 		    ((uint64_t)(HPET_MIN_CYCLES * 2) << 32) / sc->freq;
791 		t->et.et_max_period = (0xfffffffeLLU << 32) / sc->freq;
792 		t->et.et_start = hpet_start;
793 		t->et.et_stop = hpet_stop;
794 		t->et.et_priv = &sc->t[i];
795 		if (t->pcpu_master < 0 || t->pcpu_master == i) {
796 			et_register(&t->et);
797 			maxhpetet++;
798 		}
799 	}
800 	acpi_GetInteger(sc->handle, "_UID", &sc->acpi_uid);
801 
802 	make_dev_args_init(&mda);
803 	mda.mda_devsw = &hpet_cdevsw;
804 	mda.mda_uid = UID_ROOT;
805 	mda.mda_gid = GID_WHEEL;
806 	mda.mda_mode = 0644;
807 	mda.mda_si_drv1 = sc;
808 	error = make_dev_s(&mda, &sc->pdev, "hpet%d", device_get_unit(dev));
809 	if (error == 0) {
810 		sc->mmap_allow = 1;
811 		TUNABLE_INT_FETCH("hw.acpi.hpet.mmap_allow",
812 		    &sc->mmap_allow);
813 		sc->mmap_allow_write = 0;
814 		TUNABLE_INT_FETCH("hw.acpi.hpet.mmap_allow_write",
815 		    &sc->mmap_allow_write);
816 		SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
817 		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
818 		    OID_AUTO, "mmap_allow",
819 		    CTLFLAG_RW, &sc->mmap_allow, 0,
820 		    "Allow userland to memory map HPET");
821 		SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
822 		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
823 		    OID_AUTO, "mmap_allow_write",
824 		    CTLFLAG_RW, &sc->mmap_allow_write, 0,
825 		    "Allow userland write to the HPET register space");
826 	} else {
827 		device_printf(dev, "could not create /dev/hpet%d, error %d\n",
828 		    device_get_unit(dev), error);
829 	}
830 
831 	return (0);
832 }
833 
834 static int
835 hpet_detach(device_t dev)
836 {
837 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
838 
839 	/* XXX Without a tc_remove() function, we can't detach. */
840 	return (EBUSY);
841 }
842 
843 static int
844 hpet_suspend(device_t dev)
845 {
846 //	struct hpet_softc *sc;
847 
848 	/*
849 	 * Disable the timer during suspend.  The timer will not lose
850 	 * its state in S1 or S2, but we are required to disable
851 	 * it.
852 	 */
853 //	sc = device_get_softc(dev);
854 //	hpet_disable(sc);
855 
856 	return (0);
857 }
858 
859 static int
860 hpet_resume(device_t dev)
861 {
862 	struct hpet_softc *sc;
863 	struct hpet_timer *t;
864 	int i;
865 
866 	/* Re-enable the timer after a resume to keep the clock advancing. */
867 	sc = device_get_softc(dev);
868 	hpet_enable(sc);
869 	/* Restart event timers that were running on suspend. */
870 	for (i = 0; i < sc->num_timers; i++) {
871 		t = &sc->t[i];
872 #ifdef DEV_APIC
873 		if (t->irq >= 0 && (sc->legacy_route == 0 || i >= 2)) {
874 			uint64_t addr;
875 			uint32_t data;
876 
877 			if (PCIB_MAP_MSI(
878 			    device_get_parent(device_get_parent(dev)), dev,
879 			    t->irq, &addr, &data) == 0) {
880 				bus_write_4(sc->mem_res,
881 				    HPET_TIMER_FSB_ADDR(i), addr);
882 				bus_write_4(sc->mem_res,
883 				    HPET_TIMER_FSB_VAL(i), data);
884 			}
885 		}
886 #endif
887 		if (t->mode == TIMER_STOPPED)
888 			continue;
889 		t->next = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
890 		if (t->mode == TIMER_PERIODIC &&
891 		    (t->caps & HPET_TCAP_PER_INT) != 0) {
892 			t->caps |= HPET_TCNF_TYPE;
893 			t->next += t->div;
894 			bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num),
895 			    t->caps | HPET_TCNF_VAL_SET);
896 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
897 			    t->next);
898 			bus_read_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num));
899 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
900 			    t->div);
901 		} else {
902 			t->next += sc->freq / 1024;
903 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
904 			    t->next);
905 		}
906 		bus_write_4(sc->mem_res, HPET_ISR, 1 << t->num);
907 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num), t->caps);
908 	}
909 	return (0);
910 }
911 
912 /* Print some basic latency/rate information to assist in debugging. */
913 static void
914 hpet_test(struct hpet_softc *sc)
915 {
916 	int i;
917 	uint32_t u1, u2;
918 	struct bintime b0, b1, b2;
919 	struct timespec ts;
920 
921 	binuptime(&b0);
922 	binuptime(&b0);
923 	binuptime(&b1);
924 	u1 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
925 	for (i = 1; i < 1000; i++)
926 		u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
927 	binuptime(&b2);
928 	u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
929 
930 	bintime_sub(&b2, &b1);
931 	bintime_sub(&b1, &b0);
932 	bintime_sub(&b2, &b1);
933 	bintime2timespec(&b2, &ts);
934 
935 	device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n",
936 	    (long)ts.tv_sec, ts.tv_nsec, u1, u2, u2 - u1);
937 
938 	device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000);
939 }
940 
941 #ifdef DEV_APIC
942 static int
943 hpet_remap_intr(device_t dev, device_t child, u_int irq)
944 {
945 	struct hpet_softc *sc = device_get_softc(dev);
946 	struct hpet_timer *t;
947 	uint64_t addr;
948 	uint32_t data;
949 	int error, i;
950 
951 	for (i = 0; i < sc->num_timers; i++) {
952 		t = &sc->t[i];
953 		if (t->irq != irq)
954 			continue;
955 		error = PCIB_MAP_MSI(
956 		    device_get_parent(device_get_parent(dev)), dev,
957 		    irq, &addr, &data);
958 		if (error)
959 			return (error);
960 		hpet_disable(sc); /* Stop timer to avoid interrupt loss. */
961 		bus_write_4(sc->mem_res, HPET_TIMER_FSB_ADDR(i), addr);
962 		bus_write_4(sc->mem_res, HPET_TIMER_FSB_VAL(i), data);
963 		hpet_enable(sc);
964 		return (0);
965 	}
966 	return (ENOENT);
967 }
968 #endif
969 
970 static device_method_t hpet_methods[] = {
971 	/* Device interface */
972 	DEVMETHOD(device_identify, hpet_identify),
973 	DEVMETHOD(device_probe, hpet_probe),
974 	DEVMETHOD(device_attach, hpet_attach),
975 	DEVMETHOD(device_detach, hpet_detach),
976 	DEVMETHOD(device_suspend, hpet_suspend),
977 	DEVMETHOD(device_resume, hpet_resume),
978 
979 #ifdef DEV_APIC
980 	DEVMETHOD(bus_remap_intr, hpet_remap_intr),
981 #endif
982 
983 	DEVMETHOD_END
984 };
985 
986 static driver_t	hpet_driver = {
987 	"hpet",
988 	hpet_methods,
989 	sizeof(struct hpet_softc),
990 };
991 
992 DRIVER_MODULE(hpet, acpi, hpet_driver, hpet_devclass, 0, 0);
993 MODULE_DEPEND(hpet, acpi, 1, 1, 1);
994