xref: /dragonfly/sys/dev/acpica/acpi_hpet.c (revision 59b0b316)
1 /*-
2  * Copyright (c) 2005 Poul-Henning Kamp
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD: src/sys/dev/acpica/acpi_hpet.c,v 1.12.2.1.2.1 2008/11/25 02:59:29 kensmith Exp $
27  */
28 
29 #include "opt_acpi.h"
30 
31 #include <sys/param.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/systimer.h>
36 #include <sys/rman.h>
37 
38 #include "acpi.h"
39 #include "accommon.h"
40 #include "acpivar.h"
41 #include "acpi_hpet.h"
42 
43 /* Hooks for the ACPICA debugging infrastructure */
44 #define _COMPONENT	ACPI_TIMER
45 ACPI_MODULE_NAME("HPET")
46 
47 static bus_space_handle_t	acpi_hpet_bsh;
48 static bus_space_tag_t		acpi_hpet_bst;
49 static u_long			acpi_hpet_res_start;
50 
51 struct acpi_hpet_softc {
52 	device_t		dev;
53 	struct resource		*mem_res;
54 	ACPI_HANDLE		handle;
55 };
56 
57 #define DEV_HPET(x)	(acpi_get_magic(x) == (uintptr_t)&acpi_hpet_devclass)
58 
59 static sysclock_t	acpi_hpet_get_timecount(void);
60 static void		acpi_hpet_construct(struct cputimer *, sysclock_t);
61 
62 static int		acpi_hpet_identify(driver_t *, device_t);
63 static int		acpi_hpet_probe(device_t);
64 static int		acpi_hpet_attach(device_t);
65 static int		acpi_hpet_resume(device_t);
66 static int		acpi_hpet_suspend(device_t);
67 
68 static void		acpi_hpet_test(struct acpi_hpet_softc *sc);
69 static u_int		acpi_hpet_read(void);
70 static void		acpi_hpet_enable(struct acpi_hpet_softc *);
71 static void		acpi_hpet_disable(struct acpi_hpet_softc *);
72 
73 static char *hpet_ids[] = { "PNP0103", NULL };
74 
75 static struct cputimer acpi_hpet_timer = {
76 	.next		= SLIST_ENTRY_INITIALIZER,
77 	.name		= "HPET",
78 	.pri		= CPUTIMER_PRI_HPET,
79 	.type		= CPUTIMER_HPET,
80 	.count		= acpi_hpet_get_timecount,
81 	.fromhz		= cputimer_default_fromhz,
82 	.fromus		= cputimer_default_fromus,
83 	.construct	= acpi_hpet_construct,
84 	.destruct	= cputimer_default_destruct,
85 	.freq		= 0	/* determined later */
86 };
87 
88 static device_method_t acpi_hpet_methods[] = {
89 	DEVMETHOD(device_identify,	acpi_hpet_identify),
90 	DEVMETHOD(device_probe,		acpi_hpet_probe),
91 	DEVMETHOD(device_attach,	acpi_hpet_attach),
92 	DEVMETHOD(device_suspend,	acpi_hpet_suspend),
93 	DEVMETHOD(device_resume,	acpi_hpet_resume),
94 	DEVMETHOD_END
95 };
96 
97 static driver_t acpi_hpet_driver = {
98 	"acpi_hpet",
99 	acpi_hpet_methods,
100 	sizeof(struct acpi_hpet_softc),
101 };
102 
103 static devclass_t acpi_hpet_devclass;
104 DRIVER_MODULE(acpi_hpet, acpi, acpi_hpet_driver, acpi_hpet_devclass, NULL, NULL);
105 MODULE_DEPEND(acpi_hpet, acpi, 1, 1, 1);
106 
107 static u_int
108 acpi_hpet_read(void)
109 {
110 	return bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh,
111 				HPET_MAIN_COUNTER);
112 }
113 
114 /*
115  * Locate the ACPI timer using the FADT, set up and allocate the I/O resources
116  * we will be using.
117  */
118 static int
119 acpi_hpet_identify(driver_t *driver, device_t parent)
120 {
121 	ACPI_TABLE_HPET *hpet;
122 	ACPI_TABLE_HEADER *hdr;
123 	ACPI_STATUS status;
124 	device_t child;
125 
126 	/*
127 	 * Just try once, do nothing if the 'acpi' bus is rescanned.
128 	 */
129 	if (device_get_state(parent) == DS_ATTACHED)
130 		return 0;
131 
132 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
133 
134 	/* Only one HPET device can be added. */
135 	if (devclass_get_device(acpi_hpet_devclass, 0))
136 		return ENXIO;
137 
138 	/* Currently, ID and minimum clock tick info is unused. */
139 
140 	status = AcpiGetTable(ACPI_SIG_HPET, 1, &hdr);
141 	if (ACPI_FAILURE(status))
142 		return ENXIO;
143 
144 	/*
145 	 * The unit number could be derived from hdr->Sequence but we only
146 	 * support one HPET device.
147 	 */
148 	hpet = (ACPI_TABLE_HPET *)hdr;
149 	if (hpet->Sequence != 0) {
150 		kprintf("ACPI HPET table warning: Sequence is non-zero (%d)\n",
151 			hpet->Sequence);
152 	}
153 
154 	child = BUS_ADD_CHILD(parent, parent, 0, "acpi_hpet", 0);
155 	if (child == NULL) {
156 		device_printf(parent, "%s: can't add acpi_hpet0\n", __func__);
157 		return ENXIO;
158 	}
159 
160 	/* Record a magic value so we can detect this device later. */
161 	acpi_set_magic(child, (uintptr_t)&acpi_hpet_devclass);
162 
163 	acpi_hpet_res_start = hpet->Address.Address;
164 	if (bus_set_resource(child, SYS_RES_MEMORY, 0,
165 			     hpet->Address.Address, HPET_MEM_WIDTH, -1)) {
166 		device_printf(child, "could not set iomem resources: "
167 			      "0x%jx, %d\n", (uintmax_t)hpet->Address.Address,
168 			      HPET_MEM_WIDTH);
169 		return ENOMEM;
170 	}
171 	return 0;
172 }
173 
174 static int
175 acpi_hpet_probe(device_t dev)
176 {
177 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
178 
179 	if (acpi_disabled("hpet"))
180 		return ENXIO;
181 
182 	if (!DEV_HPET(dev) &&
183 	    (ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL ||
184 	     device_get_unit(dev) != 0))
185 		return ENXIO;
186 
187 	device_set_desc(dev, "High Precision Event Timer");
188 	return 0;
189 }
190 
191 static int
192 acpi_hpet_attach(device_t dev)
193 {
194 	struct acpi_hpet_softc *sc;
195 	int rid;
196 	uint32_t val, val2;
197 	uintmax_t freq;
198 
199 	ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
200 
201 	sc = device_get_softc(dev);
202 	sc->dev = dev;
203 	sc->handle = acpi_get_handle(dev);
204 
205 	rid = 0;
206 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
207 					     RF_ACTIVE);
208 	if (sc->mem_res == NULL) {
209 		/*
210 		 * We only need to make sure that main counter
211 		 * is accessable.
212 		 */
213 		device_printf(dev, "can't map %dB register space, try %dB\n",
214 			      HPET_MEM_WIDTH, HPET_MEM_WIDTH_MIN);
215 		rid = 0;
216 		sc->mem_res = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
217 				acpi_hpet_res_start,
218 				acpi_hpet_res_start + HPET_MEM_WIDTH_MIN - 1,
219 				HPET_MEM_WIDTH_MIN, RF_ACTIVE);
220 		if (sc->mem_res == NULL)
221 			return ENOMEM;
222 	}
223 
224 	/* Validate that we can access the whole region. */
225 	if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH_MIN) {
226 		device_printf(dev, "memory region width %ld too small\n",
227 			      rman_get_size(sc->mem_res));
228 		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->mem_res);
229 		return ENXIO;
230 	}
231 
232 	acpi_hpet_bsh = rman_get_bushandle(sc->mem_res);
233 	acpi_hpet_bst = rman_get_bustag(sc->mem_res);
234 
235 	/* Be sure timer is enabled. */
236 	acpi_hpet_enable(sc);
237 
238 	/* Read basic statistics about the timer. */
239 	val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_PERIOD);
240 	if (val == 0) {
241 		device_printf(dev, "invalid period\n");
242 		acpi_hpet_disable(sc);
243 		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->mem_res);
244 		return ENXIO;
245 	}
246 
247 	freq = (1000000000000000LL + val / 2) / val;
248 	if (bootverbose) {
249 		val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh,
250 				       HPET_CAPABILITIES);
251 		device_printf(dev,
252 		    "vend: 0x%x, rev: 0x%x, num: %d, opts:%s%s\n",
253 		    val >> 16, val & HPET_CAP_REV_ID,
254 		    (val & HPET_CAP_NUM_TIM) >> 8,
255 		    (val & HPET_CAP_LEG_RT) ? " legacy_route" : "",
256 		    (val & HPET_CAP_COUNT_SIZE) ? " 64-bit" : "");
257 	}
258 
259 	if (ktestenv("debug.acpi.hpet_test"))
260 		acpi_hpet_test(sc);
261 
262 	/*
263 	 * Don't attach if the timer never increments.  Since the spec
264 	 * requires it to be at least 10 MHz, it has to change in 1 us.
265 	 */
266 	val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh,
267 			       HPET_MAIN_COUNTER);
268 	DELAY(1);
269 	val2 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh,
270 				HPET_MAIN_COUNTER);
271 	if (val == val2) {
272 		device_printf(dev, "HPET never increments, disabling\n");
273 		acpi_hpet_disable(sc);
274 		bus_release_resource(dev, SYS_RES_MEMORY, rid, sc->mem_res);
275 		return ENXIO;
276 	}
277 
278 	acpi_hpet_timer.freq = freq;
279 	device_printf(dev, "frequency %u\n", acpi_hpet_timer.freq);
280 
281 	cputimer_register(&acpi_hpet_timer);
282 	cputimer_select(&acpi_hpet_timer, 0);
283 
284 	return 0;
285 }
286 
287 /*
288  * Construct the timer.  Adjust the base so the system clock does not
289  * jump weirdly.
290  */
291 static void
292 acpi_hpet_construct(struct cputimer *timer, sysclock_t oldclock)
293 {
294 	timer->base = 0;
295 	timer->base = oldclock - acpi_hpet_get_timecount();
296 }
297 
298 static sysclock_t
299 acpi_hpet_get_timecount(void)
300 {
301 	return acpi_hpet_read() + acpi_hpet_timer.base;
302 }
303 
304 static void
305 acpi_hpet_enable(struct acpi_hpet_softc *sc)
306 {
307 	uint32_t val;
308 
309 	val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG);
310 	bus_space_write_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG,
311 			  val | HPET_CNF_ENABLE);
312 }
313 
314 static void
315 acpi_hpet_disable(struct acpi_hpet_softc *sc)
316 {
317 	uint32_t val;
318 
319 	val = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG);
320 	bus_space_write_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_CONFIG,
321 			  val & ~HPET_CNF_ENABLE);
322 }
323 
324 static int
325 acpi_hpet_suspend(device_t dev)
326 {
327 	/*
328 	 * According to IA-PC HPET specification rev 1.0a
329 	 *
330 	 * Page 10, 2.3.3:
331 	 * "1. The Event Timer registers (including the main counter)
332 	 *  are not expected to be preserved through an S3, S4, or S5
333 	 *  state."
334 	 *
335 	 * Page 11, 2.3.3:
336 	 * "3. The main counter is permitted, but not required, to run
337 	 *  during S1 or S2 states. ..."
338 	 *
339 	 * These mean we are not allowed to enter any of Sx states,
340 	 * if HPET is used as the sys_cputimer.
341 	 */
342 	if (sys_cputimer != &acpi_hpet_timer) {
343 		struct acpi_hpet_softc *sc;
344 
345 		sc = device_get_softc(dev);
346 		acpi_hpet_disable(sc);
347 
348 		return 0;
349 	} else {
350 		return EOPNOTSUPP;
351 	}
352 }
353 
354 static int
355 acpi_hpet_resume(device_t dev)
356 {
357 	if (sys_cputimer != &acpi_hpet_timer) {
358 		struct acpi_hpet_softc *sc;
359 
360 		sc = device_get_softc(dev);
361 		acpi_hpet_enable(sc);
362 	}
363 	return 0;
364 }
365 
366 /* Print some basic latency/rate information to assist in debugging. */
367 static void
368 acpi_hpet_test(struct acpi_hpet_softc *sc)
369 {
370 	int i;
371 	uint32_t u1, u2;
372 	struct timeval b0, b1, b2;
373 	struct timespec ts;
374 
375 	microuptime(&b0);
376 	microuptime(&b0);
377 	microuptime(&b1);
378 	u1 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_MAIN_COUNTER);
379 	for (i = 1; i < 1000; i++) {
380 		u2 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh,
381 				      HPET_MAIN_COUNTER);
382 	}
383 	microuptime(&b2);
384 	u2 = bus_space_read_4(acpi_hpet_bst, acpi_hpet_bsh, HPET_MAIN_COUNTER);
385 
386 	timevalsub(&b2, &b1);
387 	timevalsub(&b1, &b0);
388 	timevalsub(&b2, &b1);
389 
390 	TIMEVAL_TO_TIMESPEC(&b2, &ts);
391 
392 	device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n",
393 	    (long)b2.tv_sec, b2.tv_usec, u1, u2, u2 - u1);
394 
395 	device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000);
396 }
397