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 /* Knob to disable acpi_timer device */
68 bool acpi_timer_disabled = false;
69
70 static void acpi_timer_identify(driver_t *driver, device_t parent);
71 static int acpi_timer_probe(device_t dev);
72 static int acpi_timer_attach(device_t dev);
73 static void acpi_timer_resume_handler(struct timecounter *,
74 enum power_stype);
75 static void acpi_timer_suspend_handler(struct timecounter *,
76 enum power_stype);
77 static u_int acpi_timer_get_timecount(struct timecounter *tc);
78 static u_int acpi_timer_get_timecount_safe(struct timecounter *tc);
79 static int acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS);
80
81 static device_method_t acpi_timer_methods[] = {
82 DEVMETHOD(device_identify, acpi_timer_identify),
83 DEVMETHOD(device_probe, acpi_timer_probe),
84 DEVMETHOD(device_attach, acpi_timer_attach),
85
86 DEVMETHOD_END
87 };
88
89 static driver_t acpi_timer_driver = {
90 "acpi_timer",
91 acpi_timer_methods,
92 0,
93 };
94
95 DRIVER_MODULE(acpi_timer, acpi, acpi_timer_driver, 0, 0);
96 MODULE_DEPEND(acpi_timer, acpi, 1, 1, 1);
97
98 static struct timecounter acpi_timer_timecounter = {
99 acpi_timer_get_timecount_safe, /* get_timecount function */
100 0, /* no poll_pps */
101 0, /* no default counter_mask */
102 0, /* no default frequency */
103 "ACPI", /* name */
104 -1 /* quality (chosen later) */
105 };
106
107 static __inline uint32_t
acpi_timer_read(void)108 acpi_timer_read(void)
109 {
110
111 return (bus_space_read_4(acpi_timer_bst, acpi_timer_bsh, 0));
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 void
acpi_timer_identify(driver_t * driver,device_t parent)119 acpi_timer_identify(driver_t *driver, device_t parent)
120 {
121 device_t dev;
122 rman_res_t rlen, rstart;
123 int rid, rtype;
124
125 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
126
127 if (acpi_disabled("timer") || (acpi_quirks & ACPI_Q_TIMER) ||
128 acpi_timer_dev || acpi_timer_disabled ||
129 AcpiGbl_FADT.PmTimerLength == 0)
130 return_VOID;
131
132 if ((dev = BUS_ADD_CHILD(parent, 2, "acpi_timer", 0)) == NULL) {
133 device_printf(parent, "could not add acpi_timer0\n");
134 return_VOID;
135 }
136 acpi_timer_dev = dev;
137
138 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
139 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
140 rtype = SYS_RES_MEMORY;
141 break;
142 case ACPI_ADR_SPACE_SYSTEM_IO:
143 rtype = SYS_RES_IOPORT;
144 break;
145 default:
146 return_VOID;
147 }
148 rid = 0;
149 rlen = AcpiGbl_FADT.PmTimerLength;
150 rstart = AcpiGbl_FADT.XPmTimerBlock.Address;
151 if (bus_set_resource(dev, rtype, rid, rstart, rlen))
152 device_printf(dev, "couldn't set resource (%s 0x%jx+0x%jx)\n",
153 (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen);
154 return_VOID;
155 }
156
157 static int
acpi_timer_probe(device_t dev)158 acpi_timer_probe(device_t dev)
159 {
160 int rid, rtype;
161
162 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
163
164 if (dev != acpi_timer_dev)
165 return (ENXIO);
166
167 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
168 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
169 rtype = SYS_RES_MEMORY;
170 break;
171 case ACPI_ADR_SPACE_SYSTEM_IO:
172 rtype = SYS_RES_IOPORT;
173 break;
174 default:
175 return (ENXIO);
176 }
177 rid = 0;
178 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
179 if (acpi_timer_reg == NULL) {
180 device_printf(dev, "couldn't allocate resource (%s 0x%lx)\n",
181 (rtype == SYS_RES_IOPORT) ? "port" : "mem",
182 (u_long)AcpiGbl_FADT.XPmTimerBlock.Address);
183 return (ENXIO);
184 }
185 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
186 acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
187 if (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER)
188 acpi_timer_timecounter.tc_counter_mask = 0xffffffff;
189 else
190 acpi_timer_timecounter.tc_counter_mask = 0x00ffffff;
191 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
192 acpi_timer_timecounter.tc_flags = TC_FLAGS_SUSPEND_SAFE;
193
194 acpi_timer_timecounter.tc_name = "ACPI-fast";
195 acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount;
196 acpi_timer_timecounter.tc_quality = 900;
197 tc_init(&acpi_timer_timecounter);
198
199 device_set_descf(dev, "%d-bit timer at %u.%06uMHz",
200 (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) != 0 ? 32 : 24,
201 acpi_timer_frequency / 1000000, acpi_timer_frequency % 1000000);
202
203 /* Release the resource, we'll allocate it again during attach. */
204 bus_release_resource(dev, rtype, rid, acpi_timer_reg);
205 return (0);
206 }
207
208 static int
acpi_timer_attach(device_t dev)209 acpi_timer_attach(device_t dev)
210 {
211 int rid, rtype;
212
213 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
214
215 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
216 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
217 rtype = SYS_RES_MEMORY;
218 break;
219 case ACPI_ADR_SPACE_SYSTEM_IO:
220 rtype = SYS_RES_IOPORT;
221 break;
222 default:
223 return (ENXIO);
224 }
225 rid = 0;
226 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
227 if (acpi_timer_reg == NULL)
228 return (ENXIO);
229 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
230 acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
231
232 /* Register suspend event handler. */
233 if (EVENTHANDLER_REGISTER(power_suspend, acpi_timer_suspend_handler,
234 &acpi_timer_timecounter, EVENTHANDLER_PRI_LAST) == NULL)
235 device_printf(dev, "failed to register suspend event handler\n");
236
237 return (0);
238 }
239
240 static void
acpi_timer_resume_handler(struct timecounter * newtc,enum power_stype stype)241 acpi_timer_resume_handler(struct timecounter *newtc, enum power_stype stype)
242 {
243 struct timecounter *tc;
244
245 tc = timecounter;
246 if (tc != newtc) {
247 if (bootverbose)
248 device_printf(acpi_timer_dev,
249 "restoring timecounter, %s -> %s\n",
250 tc->tc_name, newtc->tc_name);
251 (void)newtc->tc_get_timecount(newtc);
252 timecounter = newtc;
253 }
254 }
255
256 static void
acpi_timer_suspend_handler(struct timecounter * newtc,enum power_stype stype)257 acpi_timer_suspend_handler(struct timecounter *newtc, enum power_stype stype)
258 {
259 struct timecounter *tc;
260
261 /* Deregister existing resume event handler. */
262 if (acpi_timer_eh != NULL) {
263 EVENTHANDLER_DEREGISTER(power_resume, acpi_timer_eh);
264 acpi_timer_eh = NULL;
265 }
266
267 if ((timecounter->tc_flags & TC_FLAGS_SUSPEND_SAFE) != 0) {
268 /*
269 * If we are using a suspend safe timecounter, don't
270 * save/restore it across suspend/resume.
271 */
272 return;
273 }
274
275 KASSERT(newtc == &acpi_timer_timecounter,
276 ("acpi_timer_suspend_handler: wrong timecounter"));
277
278 tc = timecounter;
279 if (tc != newtc) {
280 if (bootverbose)
281 device_printf(acpi_timer_dev,
282 "switching timecounter, %s -> %s\n",
283 tc->tc_name, newtc->tc_name);
284 (void)acpi_timer_read();
285 (void)acpi_timer_read();
286 timecounter = newtc;
287 acpi_timer_eh = EVENTHANDLER_REGISTER(power_resume,
288 acpi_timer_resume_handler, tc, EVENTHANDLER_PRI_LAST);
289 }
290 }
291
292 /*
293 * Fetch current time value from reliable hardware.
294 */
295 static u_int
acpi_timer_get_timecount(struct timecounter * tc)296 acpi_timer_get_timecount(struct timecounter *tc)
297 {
298 return (acpi_timer_read());
299 }
300
301 /*
302 * Fetch current time value from hardware that may not correctly
303 * latch the counter. We need to read until we have three monotonic
304 * samples and then use the middle one, otherwise we are not protected
305 * against the fact that the bits can be wrong in two directions. If
306 * we only cared about monosity, two reads would be enough.
307 */
308 static u_int
acpi_timer_get_timecount_safe(struct timecounter * tc)309 acpi_timer_get_timecount_safe(struct timecounter *tc)
310 {
311 u_int u1, u2, u3;
312
313 u2 = acpi_timer_read();
314 u3 = acpi_timer_read();
315 do {
316 u1 = u2;
317 u2 = u3;
318 u3 = acpi_timer_read();
319 } while (u1 > u2 || u2 > u3);
320
321 return (u2);
322 }
323
324 /*
325 * Timecounter freqency adjustment interface.
326 */
327 static int
acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)328 acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)
329 {
330 int error;
331 u_int freq;
332
333 if (acpi_timer_timecounter.tc_frequency == 0)
334 return (EOPNOTSUPP);
335 freq = acpi_timer_frequency;
336 error = sysctl_handle_int(oidp, &freq, 0, req);
337 if (error == 0 && req->newptr != NULL) {
338 acpi_timer_frequency = freq;
339 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
340 }
341
342 return (error);
343 }
344
345 SYSCTL_PROC(_machdep, OID_AUTO, acpi_timer_freq,
346 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
347 acpi_timer_sysctl_freq, "I",
348 "ACPI timer frequency");
349