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
26 * $FreeBSD: src/sys/dev/acpica/acpi_hpet.c,v 1.12.2.1.2.1 2008/11/25 02:59:29 kensmith Exp $
31 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/systimer.h>
41 #include "acpi_hpet.h"
43 /* Hooks for the ACPI CA debugging infrastructure */
44 #define _COMPONENT ACPI_TIMER
45 ACPI_MODULE_NAME("HPET")
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
;
51 struct acpi_hpet_softc
{
53 struct resource
*mem_res
;
57 #define DEV_HPET(x) (acpi_get_magic(x) == (uintptr_t)&acpi_hpet_devclass)
59 static sysclock_t
acpi_hpet_get_timecount(void);
60 static void acpi_hpet_construct(struct cputimer
*, sysclock_t
);
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
);
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
*);
73 static char *hpet_ids
[] = { "PNP0103", NULL
};
75 static struct cputimer acpi_hpet_timer
= {
76 SLIST_ENTRY_INITIALIZER
,
80 acpi_hpet_get_timecount
,
81 cputimer_default_fromhz
,
82 cputimer_default_fromus
,
84 cputimer_default_destruct
,
89 static device_method_t acpi_hpet_methods
[] = {
90 DEVMETHOD(device_identify
, acpi_hpet_identify
),
91 DEVMETHOD(device_probe
, acpi_hpet_probe
),
92 DEVMETHOD(device_attach
, acpi_hpet_attach
),
93 DEVMETHOD(device_suspend
, acpi_hpet_suspend
),
94 DEVMETHOD(device_resume
, acpi_hpet_resume
),
98 static driver_t acpi_hpet_driver
= {
101 sizeof(struct acpi_hpet_softc
),
104 static devclass_t acpi_hpet_devclass
;
105 DRIVER_MODULE(acpi_hpet
, acpi
, acpi_hpet_driver
, acpi_hpet_devclass
, 0, 0);
106 MODULE_DEPEND(acpi_hpet
, acpi
, 1, 1, 1);
111 return bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
,
116 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources
120 acpi_hpet_identify(driver_t
*driver
, device_t parent
)
122 ACPI_TABLE_HPET
*hpet
;
123 ACPI_TABLE_HEADER
*hdr
;
128 * Just try once, do nothing if the 'acpi' bus is rescanned.
130 if (device_get_state(parent
) == DS_ATTACHED
)
133 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__
);
135 /* Only one HPET device can be added. */
136 if (devclass_get_device(acpi_hpet_devclass
, 0))
139 /* Currently, ID and minimum clock tick info is unused. */
141 status
= AcpiGetTable(ACPI_SIG_HPET
, 1, (ACPI_TABLE_HEADER
**)&hdr
);
142 if (ACPI_FAILURE(status
))
146 * The unit number could be derived from hdr->Sequence but we only
147 * support one HPET device.
149 hpet
= (ACPI_TABLE_HPET
*)hdr
;
150 if (hpet
->Sequence
!= 0) {
151 kprintf("ACPI HPET table warning: Sequence is non-zero (%d)\n",
155 child
= BUS_ADD_CHILD(parent
, parent
, 0, "acpi_hpet", 0);
157 device_printf(parent
, "%s: can't add acpi_hpet0\n", __func__
);
161 /* Record a magic value so we can detect this device later. */
162 acpi_set_magic(child
, (uintptr_t)&acpi_hpet_devclass
);
164 acpi_hpet_res_start
= hpet
->Address
.Address
;
165 if (bus_set_resource(child
, SYS_RES_MEMORY
, 0,
166 hpet
->Address
.Address
, HPET_MEM_WIDTH
)) {
167 device_printf(child
, "could not set iomem resources: "
168 "0x%llx, %d\n", hpet
->Address
.Address
,
176 acpi_hpet_probe(device_t dev
)
178 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__
);
180 if (!acpi_enabled("hpet"))
183 if (!DEV_HPET(dev
) &&
184 (ACPI_ID_PROBE(device_get_parent(dev
), dev
, hpet_ids
) == NULL
||
185 device_get_unit(dev
) != 0))
188 device_set_desc(dev
, "High Precision Event Timer");
193 acpi_hpet_attach(device_t dev
)
195 struct acpi_hpet_softc
*sc
;
200 ACPI_FUNCTION_TRACE((char *)(uintptr_t) __func__
);
202 sc
= device_get_softc(dev
);
204 sc
->handle
= acpi_get_handle(dev
);
207 sc
->mem_res
= bus_alloc_resource_any(dev
, SYS_RES_MEMORY
, &rid
,
209 if (sc
->mem_res
== NULL
) {
211 * We only need to make sure that main counter
214 device_printf(dev
, "can't map %dB register space, try %dB\n",
215 HPET_MEM_WIDTH
, HPET_MEM_WIDTH_MIN
);
217 sc
->mem_res
= bus_alloc_resource(dev
, SYS_RES_MEMORY
, &rid
,
219 acpi_hpet_res_start
+ HPET_MEM_WIDTH_MIN
- 1,
220 HPET_MEM_WIDTH_MIN
, RF_ACTIVE
);
221 if (sc
->mem_res
== NULL
)
225 /* Validate that we can access the whole region. */
226 if (rman_get_size(sc
->mem_res
) < HPET_MEM_WIDTH_MIN
) {
227 device_printf(dev
, "memory region width %ld too small\n",
228 rman_get_size(sc
->mem_res
));
229 bus_release_resource(dev
, SYS_RES_MEMORY
, rid
, sc
->mem_res
);
233 acpi_hpet_bsh
= rman_get_bushandle(sc
->mem_res
);
234 acpi_hpet_bst
= rman_get_bustag(sc
->mem_res
);
236 /* Be sure timer is enabled. */
237 acpi_hpet_enable(sc
);
239 /* Read basic statistics about the timer. */
240 val
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_PERIOD
);
242 device_printf(dev
, "invalid period\n");
243 acpi_hpet_disable(sc
);
244 bus_release_resource(dev
, SYS_RES_MEMORY
, rid
, sc
->mem_res
);
248 freq
= (1000000000000000LL + val
/ 2) / val
;
250 val
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
,
253 "vend: 0x%x, rev: 0x%x, num: %d, opts:%s%s\n",
254 val
>> 16, val
& HPET_CAP_REV_ID
,
255 (val
& HPET_CAP_NUM_TIM
) >> 8,
256 (val
& HPET_CAP_LEG_RT
) ? " legacy_route" : "",
257 (val
& HPET_CAP_COUNT_SIZE
) ? " 64-bit" : "");
260 if (ktestenv("debug.acpi.hpet_test"))
264 * Don't attach if the timer never increments. Since the spec
265 * requires it to be at least 10 MHz, it has to change in 1 us.
267 val
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
,
270 val2
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
,
273 device_printf(dev
, "HPET never increments, disabling\n");
274 acpi_hpet_disable(sc
);
275 bus_release_resource(dev
, SYS_RES_MEMORY
, rid
, sc
->mem_res
);
279 acpi_hpet_timer
.freq
= freq
;
280 device_printf(dev
, "frequency %u\n", acpi_hpet_timer
.freq
);
282 cputimer_register(&acpi_hpet_timer
);
283 cputimer_select(&acpi_hpet_timer
, 0);
289 * Construct the timer. Adjust the base so the system clock does not
293 acpi_hpet_construct(struct cputimer
*timer
, sysclock_t oldclock
)
296 timer
->base
= oldclock
- acpi_hpet_get_timecount();
300 acpi_hpet_get_timecount(void)
302 return acpi_hpet_read() + acpi_hpet_timer
.base
;
306 acpi_hpet_enable(struct acpi_hpet_softc
*sc
)
310 val
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_CONFIG
);
311 bus_space_write_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_CONFIG
,
312 val
| HPET_CNF_ENABLE
);
316 acpi_hpet_disable(struct acpi_hpet_softc
*sc
)
320 val
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_CONFIG
);
321 bus_space_write_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_CONFIG
,
322 val
& ~HPET_CNF_ENABLE
);
326 acpi_hpet_suspend(device_t dev
)
329 * According to IA-PC HPET specification rev 1.0a
332 * "1. The Event Timer registers (including the main counter)
333 * are not expected to be preserved through an S3, S4, or S5
337 * "3. The main counter is permitted, but not required, to run
338 * during S1 or S2 states. ..."
340 * These mean we are not allowed to enter any of Sx states,
341 * if HPET is used as the sys_cputimer.
343 if (sys_cputimer
!= &acpi_hpet_timer
) {
344 struct acpi_hpet_softc
*sc
;
346 sc
= device_get_softc(dev
);
347 acpi_hpet_disable(sc
);
356 acpi_hpet_resume(device_t dev
)
358 if (sys_cputimer
!= &acpi_hpet_timer
) {
359 struct acpi_hpet_softc
*sc
;
361 sc
= device_get_softc(dev
);
362 acpi_hpet_enable(sc
);
367 /* Print some basic latency/rate information to assist in debugging. */
369 acpi_hpet_test(struct acpi_hpet_softc
*sc
)
373 struct timeval b0
, b1
, b2
;
379 u1
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_MAIN_COUNTER
);
380 for (i
= 1; i
< 1000; i
++) {
381 u2
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
,
385 u2
= bus_space_read_4(acpi_hpet_bst
, acpi_hpet_bsh
, HPET_MAIN_COUNTER
);
387 timevalsub(&b2
, &b1
);
388 timevalsub(&b1
, &b0
);
389 timevalsub(&b2
, &b1
);
391 TIMEVAL_TO_TIMESPEC(&b2
, &ts
);
393 device_printf(sc
->dev
, "%ld.%09ld: %u ... %u = %u\n",
394 (long)b2
.tv_sec
, b2
.tv_usec
, u1
, u2
, u2
- u1
);
396 device_printf(sc
->dev
, "time per call: %ld ns\n", ts
.tv_nsec
/ 1000);