1 /*-
2 * Copyright (c) 2000, 2001 Michael Smith
3 * Copyright (c) 2000 BSDi
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 #include "opt_acpi.h"
30 #include <sys/param.h>
31 #include <sys/bus.h>
32 #include <sys/eventhandler.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
35 #include <sys/sysctl.h>
36 #include <sys/timetc.h>
37 #include <sys/power.h>
38
39 #include <machine/bus.h>
40 #include <machine/resource.h>
41 #include <sys/rman.h>
42
43 #include <contrib/dev/acpica/include/acpi.h>
44 #include <contrib/dev/acpica/include/accommon.h>
45
46 #include <dev/acpica/acpivar.h>
47 #include <dev/pci/pcivar.h>
48
49 /*
50 * A timecounter based on the free-running ACPI timer.
51 *
52 * Based on the i386-only mp_clock.c by <phk@FreeBSD.ORG>.
53 */
54
55 /* Hooks for the ACPI CA debugging infrastructure */
56 #define _COMPONENT ACPI_TIMER
57 ACPI_MODULE_NAME("TIMER")
58
59 static device_t acpi_timer_dev;
60 static struct resource *acpi_timer_reg;
61 static bus_space_handle_t acpi_timer_bsh;
62 static bus_space_tag_t acpi_timer_bst;
63 static eventhandler_tag acpi_timer_eh;
64
65 static u_int acpi_timer_frequency = 14318182 / 4;
66
67 static void acpi_timer_identify(driver_t *driver, device_t parent);
68 static int acpi_timer_probe(device_t dev);
69 static int acpi_timer_attach(device_t dev);
70 static void acpi_timer_resume_handler(struct timecounter *,
71 enum power_stype);
72 static void acpi_timer_suspend_handler(struct timecounter *,
73 enum power_stype);
74 static u_int acpi_timer_get_timecount(struct timecounter *tc);
75 static u_int acpi_timer_get_timecount_safe(struct timecounter *tc);
76 static int acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS);
77
78 static device_method_t acpi_timer_methods[] = {
79 DEVMETHOD(device_identify, acpi_timer_identify),
80 DEVMETHOD(device_probe, acpi_timer_probe),
81 DEVMETHOD(device_attach, acpi_timer_attach),
82
83 DEVMETHOD_END
84 };
85
86 static driver_t acpi_timer_driver = {
87 "acpi_timer",
88 acpi_timer_methods,
89 0,
90 };
91
92 DRIVER_MODULE(acpi_timer, acpi, acpi_timer_driver, 0, 0);
93 MODULE_DEPEND(acpi_timer, acpi, 1, 1, 1);
94
95 static struct timecounter acpi_timer_timecounter = {
96 acpi_timer_get_timecount_safe, /* get_timecount function */
97 0, /* no poll_pps */
98 0, /* no default counter_mask */
99 0, /* no default frequency */
100 "ACPI", /* name */
101 -1 /* quality (chosen later) */
102 };
103
104 static __inline uint32_t
acpi_timer_read(void)105 acpi_timer_read(void)
106 {
107
108 return (bus_space_read_4(acpi_timer_bst, acpi_timer_bsh, 0));
109 }
110
111 /*
112 * Locate the ACPI timer using the FADT, set up and allocate the I/O resources
113 * we will be using.
114 */
115 static void
acpi_timer_identify(driver_t * driver,device_t parent)116 acpi_timer_identify(driver_t *driver, device_t parent)
117 {
118 device_t dev;
119 rman_res_t rlen, rstart;
120 int rid, rtype;
121
122 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
123
124 if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) ||
125 acpi_timer_dev || AcpiGbl_FADT.PmTimerLength == 0)
126 return_VOID;
127
128 if ((dev = BUS_ADD_CHILD(parent, 2, "acpi_timer", 0)) == NULL) {
129 device_printf(parent, "could not add acpi_timer0\n");
130 return_VOID;
131 }
132 acpi_timer_dev = dev;
133
134 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
135 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
136 rtype = SYS_RES_MEMORY;
137 break;
138 case ACPI_ADR_SPACE_SYSTEM_IO:
139 rtype = SYS_RES_IOPORT;
140 break;
141 default:
142 return_VOID;
143 }
144 rid = 0;
145 rlen = AcpiGbl_FADT.PmTimerLength;
146 rstart = AcpiGbl_FADT.XPmTimerBlock.Address;
147 if (bus_set_resource(dev, rtype, rid, rstart, rlen))
148 device_printf(dev, "couldn't set resource (%s 0x%jx+0x%jx)\n",
149 (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen);
150 return_VOID;
151 }
152
153 static int
acpi_timer_probe(device_t dev)154 acpi_timer_probe(device_t dev)
155 {
156 int rid, rtype;
157
158 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
159
160 if (dev != acpi_timer_dev)
161 return (ENXIO);
162
163 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
164 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
165 rtype = SYS_RES_MEMORY;
166 break;
167 case ACPI_ADR_SPACE_SYSTEM_IO:
168 rtype = SYS_RES_IOPORT;
169 break;
170 default:
171 return (ENXIO);
172 }
173 rid = 0;
174 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
175 if (acpi_timer_reg == NULL) {
176 device_printf(dev, "couldn't allocate resource (%s 0x%lx)\n",
177 (rtype == SYS_RES_IOPORT) ? "port" : "mem",
178 (u_long)AcpiGbl_FADT.XPmTimerBlock.Address);
179 return (ENXIO);
180 }
181 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
182 acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
183 if (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER)
184 acpi_timer_timecounter.tc_counter_mask = 0xffffffff;
185 else
186 acpi_timer_timecounter.tc_counter_mask = 0x00ffffff;
187 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
188 acpi_timer_timecounter.tc_flags = TC_FLAGS_SUSPEND_SAFE;
189
190 acpi_timer_timecounter.tc_name = "ACPI-fast";
191 acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount;
192 acpi_timer_timecounter.tc_quality = 900;
193 tc_init(&acpi_timer_timecounter);
194
195 device_set_descf(dev, "%d-bit timer at %u.%06uMHz",
196 (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) != 0 ? 32 : 24,
197 acpi_timer_frequency / 1000000, acpi_timer_frequency % 1000000);
198
199 /* Release the resource, we'll allocate it again during attach. */
200 bus_release_resource(dev, rtype, rid, acpi_timer_reg);
201 return (0);
202 }
203
204 static int
acpi_timer_attach(device_t dev)205 acpi_timer_attach(device_t dev)
206 {
207 int rid, rtype;
208
209 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
210
211 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
212 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
213 rtype = SYS_RES_MEMORY;
214 break;
215 case ACPI_ADR_SPACE_SYSTEM_IO:
216 rtype = SYS_RES_IOPORT;
217 break;
218 default:
219 return (ENXIO);
220 }
221 rid = 0;
222 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
223 if (acpi_timer_reg == NULL)
224 return (ENXIO);
225 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
226 acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
227
228 /* Register suspend event handler. */
229 if (EVENTHANDLER_REGISTER(power_suspend, acpi_timer_suspend_handler,
230 &acpi_timer_timecounter, EVENTHANDLER_PRI_LAST) == NULL)
231 device_printf(dev, "failed to register suspend event handler\n");
232
233 return (0);
234 }
235
236 static void
acpi_timer_resume_handler(struct timecounter * newtc,enum power_stype stype)237 acpi_timer_resume_handler(struct timecounter *newtc, enum power_stype stype)
238 {
239 struct timecounter *tc;
240
241 tc = timecounter;
242 if (tc != newtc) {
243 if (bootverbose)
244 device_printf(acpi_timer_dev,
245 "restoring timecounter, %s -> %s\n",
246 tc->tc_name, newtc->tc_name);
247 (void)newtc->tc_get_timecount(newtc);
248 timecounter = newtc;
249 }
250 }
251
252 static void
acpi_timer_suspend_handler(struct timecounter * newtc,enum power_stype stype)253 acpi_timer_suspend_handler(struct timecounter *newtc, enum power_stype stype)
254 {
255 struct timecounter *tc;
256
257 /* Deregister existing resume event handler. */
258 if (acpi_timer_eh != NULL) {
259 EVENTHANDLER_DEREGISTER(power_resume, acpi_timer_eh);
260 acpi_timer_eh = NULL;
261 }
262
263 if ((timecounter->tc_flags & TC_FLAGS_SUSPEND_SAFE) != 0) {
264 /*
265 * If we are using a suspend safe timecounter, don't
266 * save/restore it across suspend/resume.
267 */
268 return;
269 }
270
271 KASSERT(newtc == &acpi_timer_timecounter,
272 ("acpi_timer_suspend_handler: wrong timecounter"));
273
274 tc = timecounter;
275 if (tc != newtc) {
276 if (bootverbose)
277 device_printf(acpi_timer_dev,
278 "switching timecounter, %s -> %s\n",
279 tc->tc_name, newtc->tc_name);
280 (void)acpi_timer_read();
281 (void)acpi_timer_read();
282 timecounter = newtc;
283 acpi_timer_eh = EVENTHANDLER_REGISTER(power_resume,
284 acpi_timer_resume_handler, tc, EVENTHANDLER_PRI_LAST);
285 }
286 }
287
288 /*
289 * Fetch current time value from reliable hardware.
290 */
291 static u_int
acpi_timer_get_timecount(struct timecounter * tc)292 acpi_timer_get_timecount(struct timecounter *tc)
293 {
294 return (acpi_timer_read());
295 }
296
297 /*
298 * Fetch current time value from hardware that may not correctly
299 * latch the counter. We need to read until we have three monotonic
300 * samples and then use the middle one, otherwise we are not protected
301 * against the fact that the bits can be wrong in two directions. If
302 * we only cared about monosity, two reads would be enough.
303 */
304 static u_int
acpi_timer_get_timecount_safe(struct timecounter * tc)305 acpi_timer_get_timecount_safe(struct timecounter *tc)
306 {
307 u_int u1, u2, u3;
308
309 u2 = acpi_timer_read();
310 u3 = acpi_timer_read();
311 do {
312 u1 = u2;
313 u2 = u3;
314 u3 = acpi_timer_read();
315 } while (u1 > u2 || u2 > u3);
316
317 return (u2);
318 }
319
320 /*
321 * Timecounter frequency adjustment interface.
322 */
323 static int
acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)324 acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)
325 {
326 int error;
327 u_int freq;
328
329 if (acpi_timer_timecounter.tc_frequency == 0)
330 return (EOPNOTSUPP);
331 freq = acpi_timer_frequency;
332 error = sysctl_handle_int(oidp, &freq, 0, req);
333 if (error == 0 && req->newptr != NULL) {
334 acpi_timer_frequency = freq;
335 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
336 }
337
338 return (error);
339 }
340
341 SYSCTL_PROC(_machdep, OID_AUTO, acpi_timer_freq,
342 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
343 acpi_timer_sysctl_freq, "I",
344 "ACPI timer frequency");
345