xref: /freebsd/sys/dev/acpica/acpi_hpet.c (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
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_HYGON	0x1d94
66 #define HPET_VENDID_INTEL	0x8086
67 #define HPET_VENDID_NVIDIA	0x10de
68 #define HPET_VENDID_SW		0x1166
69 
70 ACPI_SERIAL_DECL(hpet, "ACPI HPET support");
71 
72 static devclass_t hpet_devclass;
73 
74 /* ACPI CA debugging */
75 #define _COMPONENT	ACPI_TIMER
76 ACPI_MODULE_NAME("HPET")
77 
78 struct hpet_softc {
79 	device_t		dev;
80 	int			mem_rid;
81 	int			intr_rid;
82 	int			irq;
83 	int			useirq;
84 	int			legacy_route;
85 	int			per_cpu;
86 	uint32_t		allowed_irqs;
87 	struct resource		*mem_res;
88 	struct resource		*intr_res;
89 	void			*intr_handle;
90 	ACPI_HANDLE		handle;
91 	uint32_t		acpi_uid;
92 	uint64_t		freq;
93 	uint32_t		caps;
94 	struct timecounter	tc;
95 	struct hpet_timer {
96 		struct eventtimer	et;
97 		struct hpet_softc	*sc;
98 		int			num;
99 		int			mode;
100 #define	TIMER_STOPPED	0
101 #define	TIMER_PERIODIC	1
102 #define	TIMER_ONESHOT	2
103 		int			intr_rid;
104 		int			irq;
105 		int			pcpu_cpu;
106 		int			pcpu_misrouted;
107 		int			pcpu_master;
108 		int			pcpu_slaves[MAXCPU];
109 		struct resource		*intr_res;
110 		void			*intr_handle;
111 		uint32_t		caps;
112 		uint32_t		vectors;
113 		uint32_t		div;
114 		uint32_t		next;
115 		char			name[8];
116 	} 			t[32];
117 	int			num_timers;
118 	struct cdev		*pdev;
119 	int			mmap_allow;
120 	int			mmap_allow_write;
121 };
122 
123 static d_open_t hpet_open;
124 static d_mmap_t hpet_mmap;
125 
126 static struct cdevsw hpet_cdevsw = {
127 	.d_version =	D_VERSION,
128 	.d_name =	"hpet",
129 	.d_open =	hpet_open,
130 	.d_mmap =	hpet_mmap,
131 };
132 
133 static u_int hpet_get_timecount(struct timecounter *tc);
134 static void hpet_test(struct hpet_softc *sc);
135 
136 static char *hpet_ids[] = { "PNP0103", NULL };
137 
138 /* Knob to disable acpi_hpet device */
139 bool acpi_hpet_disabled = false;
140 
141 static u_int
142 hpet_get_timecount(struct timecounter *tc)
143 {
144 	struct hpet_softc *sc;
145 
146 	sc = tc->tc_priv;
147 	return (bus_read_4(sc->mem_res, HPET_MAIN_COUNTER));
148 }
149 
150 uint32_t
151 hpet_vdso_timehands(struct vdso_timehands *vdso_th, struct timecounter *tc)
152 {
153 	struct hpet_softc *sc;
154 
155 	sc = tc->tc_priv;
156 	vdso_th->th_algo = VDSO_TH_ALGO_X86_HPET;
157 	vdso_th->th_x86_shift = 0;
158 	vdso_th->th_x86_hpet_idx = device_get_unit(sc->dev);
159 	bzero(vdso_th->th_res, sizeof(vdso_th->th_res));
160 	return (sc->mmap_allow != 0);
161 }
162 
163 #ifdef COMPAT_FREEBSD32
164 uint32_t
165 hpet_vdso_timehands32(struct vdso_timehands32 *vdso_th32,
166     struct timecounter *tc)
167 {
168 	struct hpet_softc *sc;
169 
170 	sc = tc->tc_priv;
171 	vdso_th32->th_algo = VDSO_TH_ALGO_X86_HPET;
172 	vdso_th32->th_x86_shift = 0;
173 	vdso_th32->th_x86_hpet_idx = device_get_unit(sc->dev);
174 	bzero(vdso_th32->th_res, sizeof(vdso_th32->th_res));
175 	return (sc->mmap_allow != 0);
176 }
177 #endif
178 
179 static void
180 hpet_enable(struct hpet_softc *sc)
181 {
182 	uint32_t val;
183 
184 	val = bus_read_4(sc->mem_res, HPET_CONFIG);
185 	if (sc->legacy_route)
186 		val |= HPET_CNF_LEG_RT;
187 	else
188 		val &= ~HPET_CNF_LEG_RT;
189 	val |= HPET_CNF_ENABLE;
190 	bus_write_4(sc->mem_res, HPET_CONFIG, val);
191 }
192 
193 static void
194 hpet_disable(struct hpet_softc *sc)
195 {
196 	uint32_t val;
197 
198 	val = bus_read_4(sc->mem_res, HPET_CONFIG);
199 	val &= ~HPET_CNF_ENABLE;
200 	bus_write_4(sc->mem_res, HPET_CONFIG, val);
201 }
202 
203 static int
204 hpet_start(struct eventtimer *et, sbintime_t first, sbintime_t period)
205 {
206 	struct hpet_timer *mt = (struct hpet_timer *)et->et_priv;
207 	struct hpet_timer *t;
208 	struct hpet_softc *sc = mt->sc;
209 	uint32_t fdiv, now;
210 
211 	t = (mt->pcpu_master < 0) ? mt : &sc->t[mt->pcpu_slaves[curcpu]];
212 	if (period != 0) {
213 		t->mode = TIMER_PERIODIC;
214 		t->div = (sc->freq * period) >> 32;
215 	} else {
216 		t->mode = TIMER_ONESHOT;
217 		t->div = 0;
218 	}
219 	if (first != 0)
220 		fdiv = (sc->freq * first) >> 32;
221 	else
222 		fdiv = t->div;
223 	if (t->irq < 0)
224 		bus_write_4(sc->mem_res, HPET_ISR, 1 << t->num);
225 	t->caps |= HPET_TCNF_INT_ENB;
226 	now = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
227 restart:
228 	t->next = now + fdiv;
229 	if (t->mode == TIMER_PERIODIC && (t->caps & HPET_TCAP_PER_INT)) {
230 		t->caps |= HPET_TCNF_TYPE;
231 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num),
232 		    t->caps | HPET_TCNF_VAL_SET);
233 		bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
234 		    t->next);
235 		bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
236 		    t->div);
237 	} else {
238 		t->caps &= ~HPET_TCNF_TYPE;
239 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num),
240 		    t->caps);
241 		bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
242 		    t->next);
243 	}
244 	now = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
245 	if ((int32_t)(now - t->next + HPET_MIN_CYCLES) >= 0) {
246 		fdiv *= 2;
247 		goto restart;
248 	}
249 	return (0);
250 }
251 
252 static int
253 hpet_stop(struct eventtimer *et)
254 {
255 	struct hpet_timer *mt = (struct hpet_timer *)et->et_priv;
256 	struct hpet_timer *t;
257 	struct hpet_softc *sc = mt->sc;
258 
259 	t = (mt->pcpu_master < 0) ? mt : &sc->t[mt->pcpu_slaves[curcpu]];
260 	t->mode = TIMER_STOPPED;
261 	t->caps &= ~(HPET_TCNF_INT_ENB | HPET_TCNF_TYPE);
262 	bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num), t->caps);
263 	return (0);
264 }
265 
266 static int
267 hpet_intr_single(void *arg)
268 {
269 	struct hpet_timer *t = (struct hpet_timer *)arg;
270 	struct hpet_timer *mt;
271 	struct hpet_softc *sc = t->sc;
272 	uint32_t now;
273 
274 	if (t->mode == TIMER_STOPPED)
275 		return (FILTER_STRAY);
276 	/* Check that per-CPU timer interrupt reached right CPU. */
277 	if (t->pcpu_cpu >= 0 && t->pcpu_cpu != curcpu) {
278 		if ((++t->pcpu_misrouted) % 32 == 0) {
279 			printf("HPET interrupt routed to the wrong CPU"
280 			    " (timer %d CPU %d -> %d)!\n",
281 			    t->num, t->pcpu_cpu, curcpu);
282 		}
283 
284 		/*
285 		 * Reload timer, hoping that next time may be more lucky
286 		 * (system will manage proper interrupt binding).
287 		 */
288 		if ((t->mode == TIMER_PERIODIC &&
289 		    (t->caps & HPET_TCAP_PER_INT) == 0) ||
290 		    t->mode == TIMER_ONESHOT) {
291 			t->next = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER) +
292 			    sc->freq / 8;
293 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
294 			    t->next);
295 		}
296 		return (FILTER_HANDLED);
297 	}
298 	if (t->mode == TIMER_PERIODIC &&
299 	    (t->caps & HPET_TCAP_PER_INT) == 0) {
300 		t->next += t->div;
301 		now = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
302 		if ((int32_t)((now + t->div / 2) - t->next) > 0)
303 			t->next = now + t->div / 2;
304 		bus_write_4(sc->mem_res,
305 		    HPET_TIMER_COMPARATOR(t->num), t->next);
306 	} else if (t->mode == TIMER_ONESHOT)
307 		t->mode = TIMER_STOPPED;
308 	mt = (t->pcpu_master < 0) ? t : &sc->t[t->pcpu_master];
309 	if (mt->et.et_active)
310 		mt->et.et_event_cb(&mt->et, mt->et.et_arg);
311 	return (FILTER_HANDLED);
312 }
313 
314 static int
315 hpet_intr(void *arg)
316 {
317 	struct hpet_softc *sc = (struct hpet_softc *)arg;
318 	int i;
319 	uint32_t val;
320 
321 	val = bus_read_4(sc->mem_res, HPET_ISR);
322 	if (val) {
323 		bus_write_4(sc->mem_res, HPET_ISR, val);
324 		val &= sc->useirq;
325 		for (i = 0; i < sc->num_timers; i++) {
326 			if ((val & (1 << i)) == 0)
327 				continue;
328 			hpet_intr_single(&sc->t[i]);
329 		}
330 		return (FILTER_HANDLED);
331 	}
332 	return (FILTER_STRAY);
333 }
334 
335 uint32_t
336 hpet_get_uid(device_t dev)
337 {
338 	struct hpet_softc *sc;
339 
340 	sc = device_get_softc(dev);
341 	return (sc->acpi_uid);
342 }
343 
344 static ACPI_STATUS
345 hpet_find(ACPI_HANDLE handle, UINT32 level, void *context,
346     void **status)
347 {
348 	char 		**ids;
349 	uint32_t	id = (uint32_t)(uintptr_t)context;
350 	uint32_t	uid = 0;
351 
352 	for (ids = hpet_ids; *ids != NULL; ids++) {
353 		if (acpi_MatchHid(handle, *ids))
354 		        break;
355 	}
356 	if (*ids == NULL)
357 		return (AE_OK);
358 	if (ACPI_FAILURE(acpi_GetInteger(handle, "_UID", &uid)) ||
359 	    id == uid)
360 		*status = acpi_get_device(handle);
361 	return (AE_OK);
362 }
363 
364 /*
365  * Find an existing IRQ resource that matches the requested IRQ range
366  * and return its RID.  If one is not found, use a new RID.
367  */
368 static int
369 hpet_find_irq_rid(device_t dev, u_long start, u_long end)
370 {
371 	rman_res_t irq;
372 	int error, rid;
373 
374 	for (rid = 0;; rid++) {
375 		error = bus_get_resource(dev, SYS_RES_IRQ, rid, &irq, NULL);
376 		if (error != 0 || (start <= irq && irq <= end))
377 			return (rid);
378 	}
379 }
380 
381 static int
382 hpet_open(struct cdev *cdev, int oflags, int devtype, struct thread *td)
383 {
384 	struct hpet_softc *sc;
385 
386 	sc = cdev->si_drv1;
387 	if (!sc->mmap_allow)
388 		return (EPERM);
389 	else
390 		return (0);
391 }
392 
393 static int
394 hpet_mmap(struct cdev *cdev, vm_ooffset_t offset, vm_paddr_t *paddr,
395     int nprot, vm_memattr_t *memattr)
396 {
397 	struct hpet_softc *sc;
398 
399 	sc = cdev->si_drv1;
400 	if (offset >= rman_get_size(sc->mem_res))
401 		return (EINVAL);
402 	if (!sc->mmap_allow_write && (nprot & PROT_WRITE))
403 		return (EPERM);
404 	*paddr = rman_get_start(sc->mem_res) + offset;
405 	*memattr = VM_MEMATTR_UNCACHEABLE;
406 
407 	return (0);
408 }
409 
410 /* Discover the HPET via the ACPI table of the same name. */
411 static void
412 hpet_identify(driver_t *driver, device_t parent)
413 {
414 	ACPI_TABLE_HPET *hpet;
415 	ACPI_STATUS	status;
416 	device_t	child;
417 	int		i;
418 
419 	/* Only one HPET device can be added. */
420 	if (devclass_get_device(hpet_devclass, 0))
421 		return;
422 	for (i = 1; ; i++) {
423 		/* Search for HPET table. */
424 		status = AcpiGetTable(ACPI_SIG_HPET, i, (ACPI_TABLE_HEADER **)&hpet);
425 		if (ACPI_FAILURE(status))
426 			return;
427 		/* Search for HPET device with same ID. */
428 		child = NULL;
429 		AcpiWalkNamespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
430 		    100, hpet_find, NULL, (void *)(uintptr_t)hpet->Sequence,
431 		    (void *)&child);
432 		/* If found - let it be probed in normal way. */
433 		if (child) {
434 			if (bus_get_resource(child, SYS_RES_MEMORY, 0,
435 			    NULL, NULL) != 0)
436 				bus_set_resource(child, SYS_RES_MEMORY, 0,
437 				    hpet->Address.Address, HPET_MEM_WIDTH);
438 			continue;
439 		}
440 		/* If not - create it from table info. */
441 		child = BUS_ADD_CHILD(parent, 2, "hpet", 0);
442 		if (child == NULL) {
443 			printf("%s: can't add child\n", __func__);
444 			continue;
445 		}
446 		bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address,
447 		    HPET_MEM_WIDTH);
448 	}
449 }
450 
451 static int
452 hpet_probe(device_t dev)
453 {
454 	int rv;
455 
456 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
457 	if (acpi_disabled("hpet") || acpi_hpet_disabled)
458 		return (ENXIO);
459 	if (acpi_get_handle(dev) != NULL)
460 		rv = ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids, NULL);
461 	else
462 		rv = 0;
463 	if (rv <= 0)
464 		device_set_desc(dev, "High Precision Event Timer");
465 	return (rv);
466 }
467 
468 static int
469 hpet_attach(device_t dev)
470 {
471 	struct hpet_softc *sc;
472 	struct hpet_timer *t;
473 	struct make_dev_args mda;
474 	int i, j, num_msi, num_timers, num_percpu_et, num_percpu_t, cur_cpu;
475 	int pcpu_master, error;
476 	static int maxhpetet = 0;
477 	uint32_t val, val2, cvectors, dvectors;
478 	uint16_t vendor, rev;
479 
480 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
481 
482 	sc = device_get_softc(dev);
483 	sc->dev = dev;
484 	sc->handle = acpi_get_handle(dev);
485 
486 	sc->mem_rid = 0;
487 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->mem_rid,
488 	    RF_ACTIVE);
489 	if (sc->mem_res == NULL)
490 		return (ENOMEM);
491 
492 	/* Validate that we can access the whole region. */
493 	if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH) {
494 		device_printf(dev, "memory region width %jd too small\n",
495 		    rman_get_size(sc->mem_res));
496 		bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
497 		return (ENXIO);
498 	}
499 
500 	/* Be sure timer is enabled. */
501 	hpet_enable(sc);
502 
503 	/* Read basic statistics about the timer. */
504 	val = bus_read_4(sc->mem_res, HPET_PERIOD);
505 	if (val == 0) {
506 		device_printf(dev, "invalid period\n");
507 		hpet_disable(sc);
508 		bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
509 		return (ENXIO);
510 	}
511 
512 	sc->freq = (1000000000000000LL + val / 2) / val;
513 	sc->caps = bus_read_4(sc->mem_res, HPET_CAPABILITIES);
514 	vendor = (sc->caps & HPET_CAP_VENDOR_ID) >> 16;
515 	rev = sc->caps & HPET_CAP_REV_ID;
516 	num_timers = 1 + ((sc->caps & HPET_CAP_NUM_TIM) >> 8);
517 	/*
518 	 * ATI/AMD violates IA-PC HPET (High Precision Event Timers)
519 	 * Specification and provides an off by one number
520 	 * of timers/comparators.
521 	 * Additionally, they use unregistered value in VENDOR_ID field.
522 	 */
523 	if (vendor == HPET_VENDID_AMD && rev < 0x10 && num_timers > 0)
524 		num_timers--;
525 	sc->num_timers = num_timers;
526 	if (bootverbose) {
527 		device_printf(dev,
528 		    "vendor 0x%x, rev 0x%x, %jdHz%s, %d timers,%s\n",
529 		    vendor, rev, sc->freq,
530 		    (sc->caps & HPET_CAP_COUNT_SIZE) ? " 64bit" : "",
531 		    num_timers,
532 		    (sc->caps & HPET_CAP_LEG_RT) ? " legacy route" : "");
533 	}
534 	for (i = 0; i < num_timers; i++) {
535 		t = &sc->t[i];
536 		t->sc = sc;
537 		t->num = i;
538 		t->mode = TIMER_STOPPED;
539 		t->intr_rid = -1;
540 		t->irq = -1;
541 		t->pcpu_cpu = -1;
542 		t->pcpu_misrouted = 0;
543 		t->pcpu_master = -1;
544 		t->caps = bus_read_4(sc->mem_res, HPET_TIMER_CAP_CNF(i));
545 		t->vectors = bus_read_4(sc->mem_res, HPET_TIMER_CAP_CNF(i) + 4);
546 		if (bootverbose) {
547 			device_printf(dev,
548 			    " t%d: irqs 0x%08x (%d)%s%s%s\n", i,
549 			    t->vectors, (t->caps & HPET_TCNF_INT_ROUTE) >> 9,
550 			    (t->caps & HPET_TCAP_FSB_INT_DEL) ? ", MSI" : "",
551 			    (t->caps & HPET_TCAP_SIZE) ? ", 64bit" : "",
552 			    (t->caps & HPET_TCAP_PER_INT) ? ", periodic" : "");
553 		}
554 	}
555 	if (testenv("debug.acpi.hpet_test"))
556 		hpet_test(sc);
557 	/*
558 	 * Don't attach if the timer never increments.  Since the spec
559 	 * requires it to be at least 10 MHz, it has to change in 1 us.
560 	 */
561 	val = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
562 	DELAY(1);
563 	val2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
564 	if (val == val2) {
565 		device_printf(dev, "HPET never increments, disabling\n");
566 		hpet_disable(sc);
567 		bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
568 		return (ENXIO);
569 	}
570 	/* Announce first HPET as timecounter. */
571 	if (device_get_unit(dev) == 0) {
572 		sc->tc.tc_get_timecount = hpet_get_timecount,
573 		sc->tc.tc_counter_mask = ~0u,
574 		sc->tc.tc_name = "HPET",
575 		sc->tc.tc_quality = 950,
576 		sc->tc.tc_frequency = sc->freq;
577 		sc->tc.tc_priv = sc;
578 		sc->tc.tc_fill_vdso_timehands = hpet_vdso_timehands;
579 #ifdef COMPAT_FREEBSD32
580 		sc->tc.tc_fill_vdso_timehands32 = hpet_vdso_timehands32;
581 #endif
582 		tc_init(&sc->tc);
583 	}
584 	/* If not disabled - setup and announce event timers. */
585 	if (resource_int_value(device_get_name(dev), device_get_unit(dev),
586 	     "clock", &i) == 0 && i == 0)
587 	        return (0);
588 
589 	/* Check whether we can and want legacy routing. */
590 	sc->legacy_route = 0;
591 	resource_int_value(device_get_name(dev), device_get_unit(dev),
592 	     "legacy_route", &sc->legacy_route);
593 	if ((sc->caps & HPET_CAP_LEG_RT) == 0)
594 		sc->legacy_route = 0;
595 	if (sc->legacy_route) {
596 		sc->t[0].vectors = 0;
597 		sc->t[1].vectors = 0;
598 	}
599 
600 	/* Check what IRQs we want use. */
601 	/* By default allow any PCI IRQs. */
602 	sc->allowed_irqs = 0xffff0000;
603 	/*
604 	 * HPETs in AMD chipsets before SB800 have problems with IRQs >= 16
605 	 * Lower are also not always working for different reasons.
606 	 * SB800 fixed it, but seems do not implements level triggering
607 	 * properly, that makes it very unreliable - it freezes after any
608 	 * interrupt loss. Avoid legacy IRQs for AMD.
609 	 */
610 	if (vendor == HPET_VENDID_AMD || vendor == HPET_VENDID_AMD2 ||
611 	    vendor == HPET_VENDID_HYGON)
612 		sc->allowed_irqs = 0x00000000;
613 	/*
614 	 * NVidia MCP5x chipsets have number of unexplained interrupt
615 	 * problems. For some reason, using HPET interrupts breaks HDA sound.
616 	 */
617 	if (vendor == HPET_VENDID_NVIDIA && rev <= 0x01)
618 		sc->allowed_irqs = 0x00000000;
619 	/*
620 	 * ServerWorks HT1000 reported to have problems with IRQs >= 16.
621 	 * Lower IRQs are working, but allowed mask is not set correctly.
622 	 * Legacy_route mode works fine.
623 	 */
624 	if (vendor == HPET_VENDID_SW && rev <= 0x01)
625 		sc->allowed_irqs = 0x00000000;
626 	/*
627 	 * Neither QEMU nor VirtualBox report supported IRQs correctly.
628 	 * The only way to use HPET there is to specify IRQs manually
629 	 * and/or use legacy_route. Legacy_route mode works on both.
630 	 */
631 	if (vm_guest)
632 		sc->allowed_irqs = 0x00000000;
633 	/* Let user override. */
634 	resource_int_value(device_get_name(dev), device_get_unit(dev),
635 	     "allowed_irqs", &sc->allowed_irqs);
636 
637 	/* Get how much per-CPU timers we should try to provide. */
638 	sc->per_cpu = 1;
639 	resource_int_value(device_get_name(dev), device_get_unit(dev),
640 	     "per_cpu", &sc->per_cpu);
641 
642 	num_msi = 0;
643 	sc->useirq = 0;
644 	/* Find IRQ vectors for all timers. */
645 	cvectors = sc->allowed_irqs & 0xffff0000;
646 	dvectors = sc->allowed_irqs & 0x0000ffff;
647 	if (sc->legacy_route)
648 		dvectors &= 0x0000fefe;
649 	for (i = 0; i < num_timers; i++) {
650 		t = &sc->t[i];
651 		if (sc->legacy_route && i < 2)
652 			t->irq = (i == 0) ? 0 : 8;
653 #ifdef DEV_APIC
654 		else if (t->caps & HPET_TCAP_FSB_INT_DEL) {
655 			if ((j = PCIB_ALLOC_MSIX(
656 			    device_get_parent(device_get_parent(dev)), dev,
657 			    &t->irq))) {
658 				device_printf(dev,
659 				    "Can't allocate interrupt for t%d: %d\n",
660 				    i, j);
661 			}
662 		}
663 #endif
664 		else if (dvectors & t->vectors) {
665 			t->irq = ffs(dvectors & t->vectors) - 1;
666 			dvectors &= ~(1 << t->irq);
667 		}
668 		if (t->irq >= 0) {
669 			t->intr_rid = hpet_find_irq_rid(dev, t->irq, t->irq);
670 			t->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
671 			    &t->intr_rid, t->irq, t->irq, 1, RF_ACTIVE);
672 			if (t->intr_res == NULL) {
673 				t->irq = -1;
674 				device_printf(dev,
675 				    "Can't map interrupt for t%d.\n", i);
676 			} else if (bus_setup_intr(dev, t->intr_res,
677 			    INTR_TYPE_CLK, hpet_intr_single, NULL, t,
678 			    &t->intr_handle) != 0) {
679 				t->irq = -1;
680 				device_printf(dev,
681 				    "Can't setup interrupt for t%d.\n", i);
682 			} else {
683 				bus_describe_intr(dev, t->intr_res,
684 				    t->intr_handle, "t%d", i);
685 				num_msi++;
686 			}
687 		}
688 		if (t->irq < 0 && (cvectors & t->vectors) != 0) {
689 			cvectors &= t->vectors;
690 			sc->useirq |= (1 << i);
691 		}
692 	}
693 	if (sc->legacy_route && sc->t[0].irq < 0 && sc->t[1].irq < 0)
694 		sc->legacy_route = 0;
695 	if (sc->legacy_route)
696 		hpet_enable(sc);
697 	/* Group timers for per-CPU operation. */
698 	num_percpu_et = min(num_msi / mp_ncpus, sc->per_cpu);
699 	num_percpu_t = num_percpu_et * mp_ncpus;
700 	pcpu_master = 0;
701 	cur_cpu = CPU_FIRST();
702 	for (i = 0; i < num_timers; i++) {
703 		t = &sc->t[i];
704 		if (t->irq >= 0 && num_percpu_t > 0) {
705 			if (cur_cpu == CPU_FIRST())
706 				pcpu_master = i;
707 			t->pcpu_cpu = cur_cpu;
708 			t->pcpu_master = pcpu_master;
709 			sc->t[pcpu_master].
710 			    pcpu_slaves[cur_cpu] = i;
711 			bus_bind_intr(dev, t->intr_res, cur_cpu);
712 			cur_cpu = CPU_NEXT(cur_cpu);
713 			num_percpu_t--;
714 		} else if (t->irq >= 0)
715 			bus_bind_intr(dev, t->intr_res, CPU_FIRST());
716 	}
717 	bus_write_4(sc->mem_res, HPET_ISR, 0xffffffff);
718 	sc->irq = -1;
719 	/* If at least one timer needs legacy IRQ - set it up. */
720 	if (sc->useirq) {
721 		j = i = fls(cvectors) - 1;
722 		while (j > 0 && (cvectors & (1 << (j - 1))) != 0)
723 			j--;
724 		sc->intr_rid = hpet_find_irq_rid(dev, j, i);
725 		sc->intr_res = bus_alloc_resource(dev, SYS_RES_IRQ,
726 		    &sc->intr_rid, j, i, 1, RF_SHAREABLE | RF_ACTIVE);
727 		if (sc->intr_res == NULL)
728 			device_printf(dev, "Can't map interrupt.\n");
729 		else if (bus_setup_intr(dev, sc->intr_res, INTR_TYPE_CLK,
730 		    hpet_intr, NULL, sc, &sc->intr_handle) != 0) {
731 			device_printf(dev, "Can't setup interrupt.\n");
732 		} else {
733 			sc->irq = rman_get_start(sc->intr_res);
734 			/* Bind IRQ to BSP to avoid live migration. */
735 			bus_bind_intr(dev, sc->intr_res, CPU_FIRST());
736 		}
737 	}
738 	/* Program and announce event timers. */
739 	for (i = 0; i < num_timers; i++) {
740 		t = &sc->t[i];
741 		t->caps &= ~(HPET_TCNF_FSB_EN | HPET_TCNF_INT_ROUTE);
742 		t->caps &= ~(HPET_TCNF_VAL_SET | HPET_TCNF_INT_ENB);
743 		t->caps &= ~(HPET_TCNF_INT_TYPE);
744 		t->caps |= HPET_TCNF_32MODE;
745 		if (t->irq >= 0 && sc->legacy_route && i < 2) {
746 			/* Legacy route doesn't need more configuration. */
747 		} else
748 #ifdef DEV_APIC
749 		if ((t->caps & HPET_TCAP_FSB_INT_DEL) && t->irq >= 0) {
750 			uint64_t addr;
751 			uint32_t data;
752 
753 			if (PCIB_MAP_MSI(
754 			    device_get_parent(device_get_parent(dev)), dev,
755 			    t->irq, &addr, &data) == 0) {
756 				bus_write_4(sc->mem_res,
757 				    HPET_TIMER_FSB_ADDR(i), addr);
758 				bus_write_4(sc->mem_res,
759 				    HPET_TIMER_FSB_VAL(i), data);
760 				t->caps |= HPET_TCNF_FSB_EN;
761 			} else
762 				t->irq = -2;
763 		} else
764 #endif
765 		if (t->irq >= 0)
766 			t->caps |= (t->irq << 9);
767 		else if (sc->irq >= 0 && (t->vectors & (1 << sc->irq)))
768 			t->caps |= (sc->irq << 9) | HPET_TCNF_INT_TYPE;
769 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(i), t->caps);
770 		/* Skip event timers without set up IRQ. */
771 		if (t->irq < 0 &&
772 		    (sc->irq < 0 || (t->vectors & (1 << sc->irq)) == 0))
773 			continue;
774 		/* Announce the reset. */
775 		if (maxhpetet == 0)
776 			t->et.et_name = "HPET";
777 		else {
778 			sprintf(t->name, "HPET%d", maxhpetet);
779 			t->et.et_name = t->name;
780 		}
781 		t->et.et_flags = ET_FLAGS_PERIODIC | ET_FLAGS_ONESHOT;
782 		t->et.et_quality = 450;
783 		if (t->pcpu_master >= 0) {
784 			t->et.et_flags |= ET_FLAGS_PERCPU;
785 			t->et.et_quality += 100;
786 		} else if (mp_ncpus >= 8)
787 			t->et.et_quality -= 100;
788 		if ((t->caps & HPET_TCAP_PER_INT) == 0)
789 			t->et.et_quality -= 10;
790 		t->et.et_frequency = sc->freq;
791 		t->et.et_min_period =
792 		    ((uint64_t)(HPET_MIN_CYCLES * 2) << 32) / sc->freq;
793 		t->et.et_max_period = (0xfffffffeLLU << 32) / sc->freq;
794 		t->et.et_start = hpet_start;
795 		t->et.et_stop = hpet_stop;
796 		t->et.et_priv = &sc->t[i];
797 		if (t->pcpu_master < 0 || t->pcpu_master == i) {
798 			et_register(&t->et);
799 			maxhpetet++;
800 		}
801 	}
802 	acpi_GetInteger(sc->handle, "_UID", &sc->acpi_uid);
803 
804 	make_dev_args_init(&mda);
805 	mda.mda_devsw = &hpet_cdevsw;
806 	mda.mda_uid = UID_ROOT;
807 	mda.mda_gid = GID_WHEEL;
808 	mda.mda_mode = 0644;
809 	mda.mda_si_drv1 = sc;
810 	error = make_dev_s(&mda, &sc->pdev, "hpet%d", device_get_unit(dev));
811 	if (error == 0) {
812 		sc->mmap_allow = 1;
813 		TUNABLE_INT_FETCH("hw.acpi.hpet.mmap_allow",
814 		    &sc->mmap_allow);
815 		sc->mmap_allow_write = 0;
816 		TUNABLE_INT_FETCH("hw.acpi.hpet.mmap_allow_write",
817 		    &sc->mmap_allow_write);
818 		SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
819 		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
820 		    OID_AUTO, "mmap_allow",
821 		    CTLFLAG_RW, &sc->mmap_allow, 0,
822 		    "Allow userland to memory map HPET");
823 		SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
824 		    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
825 		    OID_AUTO, "mmap_allow_write",
826 		    CTLFLAG_RW, &sc->mmap_allow_write, 0,
827 		    "Allow userland write to the HPET register space");
828 	} else {
829 		device_printf(dev, "could not create /dev/hpet%d, error %d\n",
830 		    device_get_unit(dev), error);
831 	}
832 
833 	return (0);
834 }
835 
836 static int
837 hpet_detach(device_t dev)
838 {
839 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
840 
841 	/* XXX Without a tc_remove() function, we can't detach. */
842 	return (EBUSY);
843 }
844 
845 static int
846 hpet_suspend(device_t dev)
847 {
848 //	struct hpet_softc *sc;
849 
850 	/*
851 	 * Disable the timer during suspend.  The timer will not lose
852 	 * its state in S1 or S2, but we are required to disable
853 	 * it.
854 	 */
855 //	sc = device_get_softc(dev);
856 //	hpet_disable(sc);
857 
858 	return (0);
859 }
860 
861 static int
862 hpet_resume(device_t dev)
863 {
864 	struct hpet_softc *sc;
865 	struct hpet_timer *t;
866 	int i;
867 
868 	/* Re-enable the timer after a resume to keep the clock advancing. */
869 	sc = device_get_softc(dev);
870 	hpet_enable(sc);
871 	/* Restart event timers that were running on suspend. */
872 	for (i = 0; i < sc->num_timers; i++) {
873 		t = &sc->t[i];
874 #ifdef DEV_APIC
875 		if (t->irq >= 0 && (sc->legacy_route == 0 || i >= 2)) {
876 			uint64_t addr;
877 			uint32_t data;
878 
879 			if (PCIB_MAP_MSI(
880 			    device_get_parent(device_get_parent(dev)), dev,
881 			    t->irq, &addr, &data) == 0) {
882 				bus_write_4(sc->mem_res,
883 				    HPET_TIMER_FSB_ADDR(i), addr);
884 				bus_write_4(sc->mem_res,
885 				    HPET_TIMER_FSB_VAL(i), data);
886 			}
887 		}
888 #endif
889 		if (t->mode == TIMER_STOPPED)
890 			continue;
891 		t->next = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
892 		if (t->mode == TIMER_PERIODIC &&
893 		    (t->caps & HPET_TCAP_PER_INT) != 0) {
894 			t->caps |= HPET_TCNF_TYPE;
895 			t->next += t->div;
896 			bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num),
897 			    t->caps | HPET_TCNF_VAL_SET);
898 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
899 			    t->next);
900 			bus_read_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num));
901 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
902 			    t->div);
903 		} else {
904 			t->next += sc->freq / 1024;
905 			bus_write_4(sc->mem_res, HPET_TIMER_COMPARATOR(t->num),
906 			    t->next);
907 		}
908 		bus_write_4(sc->mem_res, HPET_ISR, 1 << t->num);
909 		bus_write_4(sc->mem_res, HPET_TIMER_CAP_CNF(t->num), t->caps);
910 	}
911 	return (0);
912 }
913 
914 /* Print some basic latency/rate information to assist in debugging. */
915 static void
916 hpet_test(struct hpet_softc *sc)
917 {
918 	int i;
919 	uint32_t u1, u2;
920 	struct bintime b0, b1, b2;
921 	struct timespec ts;
922 
923 	binuptime(&b0);
924 	binuptime(&b0);
925 	binuptime(&b1);
926 	u1 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
927 	for (i = 1; i < 1000; i++)
928 		u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
929 	binuptime(&b2);
930 	u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
931 
932 	bintime_sub(&b2, &b1);
933 	bintime_sub(&b1, &b0);
934 	bintime_sub(&b2, &b1);
935 	bintime2timespec(&b2, &ts);
936 
937 	device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n",
938 	    (long)ts.tv_sec, ts.tv_nsec, u1, u2, u2 - u1);
939 
940 	device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000);
941 }
942 
943 #ifdef DEV_APIC
944 static int
945 hpet_remap_intr(device_t dev, device_t child, u_int irq)
946 {
947 	struct hpet_softc *sc = device_get_softc(dev);
948 	struct hpet_timer *t;
949 	uint64_t addr;
950 	uint32_t data;
951 	int error, i;
952 
953 	for (i = 0; i < sc->num_timers; i++) {
954 		t = &sc->t[i];
955 		if (t->irq != irq)
956 			continue;
957 		error = PCIB_MAP_MSI(
958 		    device_get_parent(device_get_parent(dev)), dev,
959 		    irq, &addr, &data);
960 		if (error)
961 			return (error);
962 		hpet_disable(sc); /* Stop timer to avoid interrupt loss. */
963 		bus_write_4(sc->mem_res, HPET_TIMER_FSB_ADDR(i), addr);
964 		bus_write_4(sc->mem_res, HPET_TIMER_FSB_VAL(i), data);
965 		hpet_enable(sc);
966 		return (0);
967 	}
968 	return (ENOENT);
969 }
970 #endif
971 
972 static device_method_t hpet_methods[] = {
973 	/* Device interface */
974 	DEVMETHOD(device_identify, hpet_identify),
975 	DEVMETHOD(device_probe, hpet_probe),
976 	DEVMETHOD(device_attach, hpet_attach),
977 	DEVMETHOD(device_detach, hpet_detach),
978 	DEVMETHOD(device_suspend, hpet_suspend),
979 	DEVMETHOD(device_resume, hpet_resume),
980 
981 #ifdef DEV_APIC
982 	DEVMETHOD(bus_remap_intr, hpet_remap_intr),
983 #endif
984 
985 	DEVMETHOD_END
986 };
987 
988 static driver_t	hpet_driver = {
989 	"hpet",
990 	hpet_methods,
991 	sizeof(struct hpet_softc),
992 };
993 
994 DRIVER_MODULE(hpet, acpi, hpet_driver, hpet_devclass, 0, 0);
995 MODULE_DEPEND(hpet, acpi, 1, 1, 1);
996