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
38 #include <machine/bus.h>
39 #include <machine/resource.h>
40 #include <sys/rman.h>
41
42 #include <contrib/dev/acpica/include/acpi.h>
43 #include <contrib/dev/acpica/include/accommon.h>
44
45 #include <dev/acpica/acpivar.h>
46 #include <dev/pci/pcivar.h>
47
48 /*
49 * A timecounter based on the free-running ACPI timer.
50 *
51 * Based on the i386-only mp_clock.c by <phk@FreeBSD.ORG>.
52 */
53
54 /* Hooks for the ACPI CA debugging infrastructure */
55 #define _COMPONENT ACPI_TIMER
56 ACPI_MODULE_NAME("TIMER")
57
58 static device_t acpi_timer_dev;
59 static struct resource *acpi_timer_reg;
60 static bus_space_handle_t acpi_timer_bsh;
61 static bus_space_tag_t acpi_timer_bst;
62 static eventhandler_tag acpi_timer_eh;
63
64 static u_int acpi_timer_frequency = 14318182 / 4;
65
66 /* Knob to disable acpi_timer device */
67 bool acpi_timer_disabled = false;
68
69 static void acpi_timer_identify(driver_t *driver, device_t parent);
70 static int acpi_timer_probe(device_t dev);
71 static int acpi_timer_attach(device_t dev);
72 static void acpi_timer_resume_handler(struct timecounter *);
73 static void acpi_timer_suspend_handler(struct timecounter *);
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 || acpi_timer_disabled ||
126 AcpiGbl_FADT.PmTimerLength == 0)
127 return_VOID;
128
129 if ((dev = BUS_ADD_CHILD(parent, 2, "acpi_timer", 0)) == NULL) {
130 device_printf(parent, "could not add acpi_timer0\n");
131 return_VOID;
132 }
133 acpi_timer_dev = dev;
134
135 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
136 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
137 rtype = SYS_RES_MEMORY;
138 break;
139 case ACPI_ADR_SPACE_SYSTEM_IO:
140 rtype = SYS_RES_IOPORT;
141 break;
142 default:
143 return_VOID;
144 }
145 rid = 0;
146 rlen = AcpiGbl_FADT.PmTimerLength;
147 rstart = AcpiGbl_FADT.XPmTimerBlock.Address;
148 if (bus_set_resource(dev, rtype, rid, rstart, rlen))
149 device_printf(dev, "couldn't set resource (%s 0x%jx+0x%jx)\n",
150 (rtype == SYS_RES_IOPORT) ? "port" : "mem", rstart, rlen);
151 return_VOID;
152 }
153
154 static int
acpi_timer_probe(device_t dev)155 acpi_timer_probe(device_t dev)
156 {
157 int rid, rtype;
158
159 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
160
161 if (dev != acpi_timer_dev)
162 return (ENXIO);
163
164 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
165 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
166 rtype = SYS_RES_MEMORY;
167 break;
168 case ACPI_ADR_SPACE_SYSTEM_IO:
169 rtype = SYS_RES_IOPORT;
170 break;
171 default:
172 return (ENXIO);
173 }
174 rid = 0;
175 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
176 if (acpi_timer_reg == NULL) {
177 device_printf(dev, "couldn't allocate resource (%s 0x%lx)\n",
178 (rtype == SYS_RES_IOPORT) ? "port" : "mem",
179 (u_long)AcpiGbl_FADT.XPmTimerBlock.Address);
180 return (ENXIO);
181 }
182 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
183 acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
184 if (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER)
185 acpi_timer_timecounter.tc_counter_mask = 0xffffffff;
186 else
187 acpi_timer_timecounter.tc_counter_mask = 0x00ffffff;
188 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
189 acpi_timer_timecounter.tc_flags = TC_FLAGS_SUSPEND_SAFE;
190
191 acpi_timer_timecounter.tc_name = "ACPI-fast";
192 acpi_timer_timecounter.tc_get_timecount = acpi_timer_get_timecount;
193 acpi_timer_timecounter.tc_quality = 900;
194 tc_init(&acpi_timer_timecounter);
195
196 device_set_descf(dev, "%d-bit timer at %u.%06uMHz",
197 (AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) != 0 ? 32 : 24,
198 acpi_timer_frequency / 1000000, acpi_timer_frequency % 1000000);
199
200 /* Release the resource, we'll allocate it again during attach. */
201 bus_release_resource(dev, rtype, rid, acpi_timer_reg);
202 return (0);
203 }
204
205 static int
acpi_timer_attach(device_t dev)206 acpi_timer_attach(device_t dev)
207 {
208 int rid, rtype;
209
210 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
211
212 switch (AcpiGbl_FADT.XPmTimerBlock.SpaceId) {
213 case ACPI_ADR_SPACE_SYSTEM_MEMORY:
214 rtype = SYS_RES_MEMORY;
215 break;
216 case ACPI_ADR_SPACE_SYSTEM_IO:
217 rtype = SYS_RES_IOPORT;
218 break;
219 default:
220 return (ENXIO);
221 }
222 rid = 0;
223 acpi_timer_reg = bus_alloc_resource_any(dev, rtype, &rid, RF_ACTIVE);
224 if (acpi_timer_reg == NULL)
225 return (ENXIO);
226 acpi_timer_bsh = rman_get_bushandle(acpi_timer_reg);
227 acpi_timer_bst = rman_get_bustag(acpi_timer_reg);
228
229 /* Register suspend event handler. */
230 if (EVENTHANDLER_REGISTER(power_suspend, acpi_timer_suspend_handler,
231 &acpi_timer_timecounter, EVENTHANDLER_PRI_LAST) == NULL)
232 device_printf(dev, "failed to register suspend event handler\n");
233
234 return (0);
235 }
236
237 static void
acpi_timer_resume_handler(struct timecounter * newtc)238 acpi_timer_resume_handler(struct timecounter *newtc)
239 {
240 struct timecounter *tc;
241
242 tc = timecounter;
243 if (tc != newtc) {
244 if (bootverbose)
245 device_printf(acpi_timer_dev,
246 "restoring timecounter, %s -> %s\n",
247 tc->tc_name, newtc->tc_name);
248 (void)newtc->tc_get_timecount(newtc);
249 timecounter = newtc;
250 }
251 }
252
253 static void
acpi_timer_suspend_handler(struct timecounter * newtc)254 acpi_timer_suspend_handler(struct timecounter *newtc)
255 {
256 struct timecounter *tc;
257
258 /* Deregister existing resume event handler. */
259 if (acpi_timer_eh != NULL) {
260 EVENTHANDLER_DEREGISTER(power_resume, acpi_timer_eh);
261 acpi_timer_eh = NULL;
262 }
263
264 if ((timecounter->tc_flags & TC_FLAGS_SUSPEND_SAFE) != 0) {
265 /*
266 * If we are using a suspend safe timecounter, don't
267 * save/restore it across suspend/resume.
268 */
269 return;
270 }
271
272 KASSERT(newtc == &acpi_timer_timecounter,
273 ("acpi_timer_suspend_handler: wrong timecounter"));
274
275 tc = timecounter;
276 if (tc != newtc) {
277 if (bootverbose)
278 device_printf(acpi_timer_dev,
279 "switching timecounter, %s -> %s\n",
280 tc->tc_name, newtc->tc_name);
281 (void)acpi_timer_read();
282 (void)acpi_timer_read();
283 timecounter = newtc;
284 acpi_timer_eh = EVENTHANDLER_REGISTER(power_resume,
285 acpi_timer_resume_handler, tc, EVENTHANDLER_PRI_LAST);
286 }
287 }
288
289 /*
290 * Fetch current time value from reliable hardware.
291 */
292 static u_int
acpi_timer_get_timecount(struct timecounter * tc)293 acpi_timer_get_timecount(struct timecounter *tc)
294 {
295 return (acpi_timer_read());
296 }
297
298 /*
299 * Fetch current time value from hardware that may not correctly
300 * latch the counter. We need to read until we have three monotonic
301 * samples and then use the middle one, otherwise we are not protected
302 * against the fact that the bits can be wrong in two directions. If
303 * we only cared about monosity, two reads would be enough.
304 */
305 static u_int
acpi_timer_get_timecount_safe(struct timecounter * tc)306 acpi_timer_get_timecount_safe(struct timecounter *tc)
307 {
308 u_int u1, u2, u3;
309
310 u2 = acpi_timer_read();
311 u3 = acpi_timer_read();
312 do {
313 u1 = u2;
314 u2 = u3;
315 u3 = acpi_timer_read();
316 } while (u1 > u2 || u2 > u3);
317
318 return (u2);
319 }
320
321 /*
322 * Timecounter freqency adjustment interface.
323 */
324 static int
acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)325 acpi_timer_sysctl_freq(SYSCTL_HANDLER_ARGS)
326 {
327 int error;
328 u_int freq;
329
330 if (acpi_timer_timecounter.tc_frequency == 0)
331 return (EOPNOTSUPP);
332 freq = acpi_timer_frequency;
333 error = sysctl_handle_int(oidp, &freq, 0, req);
334 if (error == 0 && req->newptr != NULL) {
335 acpi_timer_frequency = freq;
336 acpi_timer_timecounter.tc_frequency = acpi_timer_frequency;
337 }
338
339 return (error);
340 }
341
342 SYSCTL_PROC(_machdep, OID_AUTO, acpi_timer_freq,
343 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
344 acpi_timer_sysctl_freq, "I",
345 "ACPI timer frequency");
346