2 * Copyright (c) 2005 Poul-Henning Kamp
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
37 #include <sys/timetc.h>
39 #include <contrib/dev/acpica/include/acpi.h>
40 #include <contrib/dev/acpica/include/accommon.h>
42 #include <dev/acpica/acpivar.h>
43 #include <dev/acpica/acpi_hpet.h>
45 #define HPET_VENDID_AMD 0x4353
46 #define HPET_VENDID_INTEL 0x8086
48 ACPI_SERIAL_DECL(hpet, "ACPI HPET support");
50 static devclass_t acpi_hpet_devclass;
52 /* ACPI CA debugging */
53 #define _COMPONENT ACPI_TIMER
54 ACPI_MODULE_NAME("HPET")
56 struct acpi_hpet_softc {
58 struct resource *mem_res;
62 static u_int hpet_get_timecount(struct timecounter *tc);
63 static void acpi_hpet_test(struct acpi_hpet_softc *sc);
65 static char *hpet_ids[] = { "PNP0103", NULL };
67 struct timecounter hpet_timecounter = {
68 .tc_get_timecount = hpet_get_timecount,
69 .tc_counter_mask = ~0u,
75 hpet_get_timecount(struct timecounter *tc)
77 struct acpi_hpet_softc *sc;
80 return (bus_read_4(sc->mem_res, HPET_MAIN_COUNTER));
84 hpet_enable(struct acpi_hpet_softc *sc)
88 val = bus_read_4(sc->mem_res, HPET_CONFIG);
89 val &= ~HPET_CNF_LEG_RT;
90 val |= HPET_CNF_ENABLE;
91 bus_write_4(sc->mem_res, HPET_CONFIG, val);
95 hpet_disable(struct acpi_hpet_softc *sc)
99 val = bus_read_4(sc->mem_res, HPET_CONFIG);
100 val &= ~HPET_CNF_ENABLE;
101 bus_write_4(sc->mem_res, HPET_CONFIG, val);
105 acpi_hpet_find(ACPI_HANDLE handle, UINT32 level, void *context,
109 uint32_t id = (uint32_t)(uintptr_t)context;
112 for (ids = hpet_ids; *ids != NULL; ids++) {
113 if (acpi_MatchHid(handle, *ids))
118 if (ACPI_FAILURE(acpi_GetInteger(handle, "_UID", &uid)))
121 *((int *)status) = 1;
125 /* Discover the HPET via the ACPI table of the same name. */
127 acpi_hpet_identify(driver_t *driver, device_t parent)
129 ACPI_TABLE_HPET *hpet;
134 /* Only one HPET device can be added. */
135 if (devclass_get_device(acpi_hpet_devclass, 0))
138 /* Search for HPET table. */
139 status = AcpiGetTable(ACPI_SIG_HPET, i, (ACPI_TABLE_HEADER **)&hpet);
140 if (ACPI_FAILURE(status))
142 /* Search for HPET device with same ID. */
144 AcpiWalkNamespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
145 100, acpi_hpet_find, NULL, (void *)(uintptr_t)hpet->Sequence, (void *)&found);
146 /* If found - let it be probed in normal way. */
149 /* If not - create it from table info. */
150 child = BUS_ADD_CHILD(parent, ACPI_DEV_BASE_ORDER, "acpi_hpet", 0);
152 printf("%s: can't add child\n", __func__);
155 bus_set_resource(child, SYS_RES_MEMORY, 0, hpet->Address.Address,
161 acpi_hpet_probe(device_t dev)
163 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
165 if (acpi_disabled("hpet"))
167 if (acpi_get_handle(dev) != NULL &&
168 ACPI_ID_PROBE(device_get_parent(dev), dev, hpet_ids) == NULL)
171 device_set_desc(dev, "High Precision Event Timer");
176 acpi_hpet_attach(device_t dev)
178 struct acpi_hpet_softc *sc;
184 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
186 sc = device_get_softc(dev);
188 sc->handle = acpi_get_handle(dev);
191 sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
193 if (sc->mem_res == NULL)
196 /* Validate that we can access the whole region. */
197 if (rman_get_size(sc->mem_res) < HPET_MEM_WIDTH) {
198 device_printf(dev, "memory region width %ld too small\n",
199 rman_get_size(sc->mem_res));
200 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
204 /* Be sure timer is enabled. */
207 /* Read basic statistics about the timer. */
208 val = bus_read_4(sc->mem_res, HPET_PERIOD);
210 device_printf(dev, "invalid period\n");
212 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
216 freq = (1000000000000000LL + val / 2) / val;
218 val = bus_read_4(sc->mem_res, HPET_CAPABILITIES);
221 * ATI/AMD violates IA-PC HPET (High Precision Event Timers)
222 * Specification and provides an off by one number
223 * of timers/comparators.
224 * Additionally, they use unregistered value in VENDOR_ID field.
226 num_timers = 1 + ((val & HPET_CAP_NUM_TIM) >> 8);
228 if (vendor == HPET_VENDID_AMD && num_timers > 0)
231 "vend: 0x%x rev: 0x%x num: %d hz: %jd opts:%s%s\n",
232 vendor, val & HPET_CAP_REV_ID,
234 (val & HPET_CAP_LEG_RT) ? " legacy_route" : "",
235 (val & HPET_CAP_COUNT_SIZE) ? " 64-bit" : "");
238 if (testenv("debug.acpi.hpet_test"))
242 * Don't attach if the timer never increments. Since the spec
243 * requires it to be at least 10 MHz, it has to change in 1 us.
245 val = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
247 val2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
249 device_printf(dev, "HPET never increments, disabling\n");
251 bus_free_resource(dev, SYS_RES_MEMORY, sc->mem_res);
254 /* Announce first HPET as timecounter. */
255 if (device_get_unit(dev) == 0) {
256 hpet_timecounter.tc_frequency = freq;
257 hpet_timecounter.tc_priv = sc;
258 tc_init(&hpet_timecounter);
264 acpi_hpet_detach(device_t dev)
266 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__);
268 /* XXX Without a tc_remove() function, we can't detach. */
273 acpi_hpet_suspend(device_t dev)
275 struct acpi_hpet_softc *sc;
278 * Disable the timer during suspend. The timer will not lose
279 * its state in S1 or S2, but we are required to disable
282 sc = device_get_softc(dev);
289 acpi_hpet_resume(device_t dev)
291 struct acpi_hpet_softc *sc;
293 /* Re-enable the timer after a resume to keep the clock advancing. */
294 sc = device_get_softc(dev);
300 /* Print some basic latency/rate information to assist in debugging. */
302 acpi_hpet_test(struct acpi_hpet_softc *sc)
306 struct bintime b0, b1, b2;
312 u1 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
313 for (i = 1; i < 1000; i++)
314 u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
316 u2 = bus_read_4(sc->mem_res, HPET_MAIN_COUNTER);
318 bintime_sub(&b2, &b1);
319 bintime_sub(&b1, &b0);
320 bintime_sub(&b2, &b1);
321 bintime2timespec(&b2, &ts);
323 device_printf(sc->dev, "%ld.%09ld: %u ... %u = %u\n",
324 (long)ts.tv_sec, ts.tv_nsec, u1, u2, u2 - u1);
326 device_printf(sc->dev, "time per call: %ld ns\n", ts.tv_nsec / 1000);
329 static device_method_t acpi_hpet_methods[] = {
330 /* Device interface */
331 DEVMETHOD(device_identify, acpi_hpet_identify),
332 DEVMETHOD(device_probe, acpi_hpet_probe),
333 DEVMETHOD(device_attach, acpi_hpet_attach),
334 DEVMETHOD(device_detach, acpi_hpet_detach),
335 DEVMETHOD(device_suspend, acpi_hpet_suspend),
336 DEVMETHOD(device_resume, acpi_hpet_resume),
341 static driver_t acpi_hpet_driver = {
344 sizeof(struct acpi_hpet_softc),
348 DRIVER_MODULE(acpi_hpet, acpi, acpi_hpet_driver, acpi_hpet_devclass, 0, 0);
349 MODULE_DEPEND(acpi_hpet, acpi, 1, 1, 1);