acpi_cpu_pstate.c revision 1.11 1 /* $NetBSD: acpi_cpu_pstate.c,v 1.11 2010/08/11 16:22:18 jruoho Exp $ */
2
3 /*-
4 * Copyright (c) 2010 Jukka Ruohonen <jruohonen (at) iki.fi>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: acpi_cpu_pstate.c,v 1.11 2010/08/11 16:22:18 jruoho Exp $");
31
32 #include <sys/param.h>
33 #include <sys/evcnt.h>
34 #include <sys/kmem.h>
35 #include <sys/once.h>
36
37 #include <dev/acpi/acpireg.h>
38 #include <dev/acpi/acpivar.h>
39 #include <dev/acpi/acpi_cpu.h>
40
41 #define _COMPONENT ACPI_BUS_COMPONENT
42 ACPI_MODULE_NAME ("acpi_cpu_pstate")
43
44 static void acpicpu_pstate_attach_print(struct acpicpu_softc *);
45 static void acpicpu_pstate_attach_evcnt(struct acpicpu_softc *);
46 static void acpicpu_pstate_detach_evcnt(struct acpicpu_softc *);
47 static ACPI_STATUS acpicpu_pstate_pss(struct acpicpu_softc *sc);
48 static ACPI_STATUS acpicpu_pstate_pss_add(struct acpicpu_pstate *,
49 ACPI_OBJECT *);
50 static ACPI_STATUS acpicpu_pstate_pct(struct acpicpu_softc *);
51 static int acpicpu_pstate_max(struct acpicpu_softc *);
52 static void acpicpu_pstate_change(struct acpicpu_softc *);
53 static void acpicpu_pstate_bios(void);
54
55 void
56 acpicpu_pstate_attach(device_t self)
57 {
58 struct acpicpu_softc *sc = device_private(self);
59 const char *str;
60 ACPI_STATUS rv;
61
62 rv = acpicpu_pstate_pss(sc);
63
64 if (ACPI_FAILURE(rv)) {
65 str = "_PSS";
66 goto fail;
67 }
68
69 rv = acpicpu_pstate_pct(sc);
70
71 if (rv == AE_SUPPORT) {
72 aprint_error_dev(sc->sc_dev, "CPU not supported\n");
73 return;
74 }
75
76 if (ACPI_FAILURE(rv)) {
77 str = "_PCT";
78 goto fail;
79 }
80
81 rv = acpicpu_pstate_max(sc);
82
83 if (rv == 0)
84 sc->sc_flags |= ACPICPU_FLAG_P_PPC;
85
86 sc->sc_flags |= ACPICPU_FLAG_P;
87 sc->sc_pstate_current = sc->sc_pstate[0].ps_freq;
88
89 acpicpu_pstate_bios();
90 acpicpu_pstate_attach_evcnt(sc);
91 acpicpu_pstate_attach_print(sc);
92
93 return;
94
95 fail:
96 aprint_error_dev(sc->sc_dev, "failed to evaluate "
97 "%s: %s\n", str, AcpiFormatException(rv));
98 }
99
100 static void
101 acpicpu_pstate_attach_print(struct acpicpu_softc *sc)
102 {
103 const uint8_t method = sc->sc_pstate_control.reg_spaceid;
104 struct acpicpu_pstate *ps;
105 const char *str;
106 uint32_t i;
107
108 str = (method != ACPI_ADR_SPACE_SYSTEM_IO) ? "FFH" : "I/O";
109
110 for (i = 0; i < sc->sc_pstate_count; i++) {
111
112 ps = &sc->sc_pstate[i];
113
114 if (ps->ps_freq == 0)
115 continue;
116
117 aprint_debug_dev(sc->sc_dev, "P%d: %3s, "
118 "lat %3u us, pow %5u mW, %4u MHz\n",
119 i, str, ps->ps_latency, ps->ps_power, ps->ps_freq);
120 }
121 }
122
123 static void
124 acpicpu_pstate_attach_evcnt(struct acpicpu_softc *sc)
125 {
126 struct acpicpu_pstate *ps;
127 uint32_t i;
128
129 for (i = 0; i < sc->sc_pstate_count; i++) {
130
131 ps = &sc->sc_pstate[i];
132
133 if (ps->ps_freq == 0)
134 continue;
135
136 (void)snprintf(ps->ps_name, sizeof(ps->ps_name),
137 "P%u (%u MHz)", i, ps->ps_freq);
138
139 evcnt_attach_dynamic(&ps->ps_evcnt, EVCNT_TYPE_MISC,
140 NULL, device_xname(sc->sc_dev), ps->ps_name);
141 }
142 }
143
144 int
145 acpicpu_pstate_detach(device_t self)
146 {
147 struct acpicpu_softc *sc = device_private(self);
148 static ONCE_DECL(once_detach);
149 size_t size;
150 int rv;
151
152 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0)
153 return 0;
154
155 rv = RUN_ONCE(&once_detach, acpicpu_md_pstate_stop);
156
157 if (rv != 0)
158 return rv;
159
160 size = sc->sc_pstate_count * sizeof(*sc->sc_pstate);
161
162 if (sc->sc_pstate != NULL)
163 kmem_free(sc->sc_pstate, size);
164
165 sc->sc_flags &= ~ACPICPU_FLAG_P;
166 acpicpu_pstate_detach_evcnt(sc);
167
168 return 0;
169 }
170
171 static void
172 acpicpu_pstate_detach_evcnt(struct acpicpu_softc *sc)
173 {
174 struct acpicpu_pstate *ps;
175 uint32_t i;
176
177 for (i = 0; i < sc->sc_pstate_count; i++) {
178
179 ps = &sc->sc_pstate[i];
180
181 if (ps->ps_freq != 0)
182 evcnt_detach(&ps->ps_evcnt);
183 }
184 }
185
186 int
187 acpicpu_pstate_start(device_t self)
188 {
189 struct acpicpu_softc *sc = device_private(self);
190 static ONCE_DECL(once_start);
191
192 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0)
193 return 0;
194
195 return RUN_ONCE(&once_start, acpicpu_md_pstate_start);
196 }
197
198 bool
199 acpicpu_pstate_suspend(device_t self)
200 {
201
202 return true;
203 }
204
205 bool
206 acpicpu_pstate_resume(device_t self)
207 {
208 static const ACPI_OSD_EXEC_CALLBACK func = acpicpu_pstate_callback;
209 struct acpicpu_softc *sc = device_private(self);
210
211 KASSERT((sc->sc_flags & ACPICPU_FLAG_P) != 0);
212
213 if ((sc->sc_flags & ACPICPU_FLAG_P_PPC) != 0)
214 (void)AcpiOsExecute(OSL_NOTIFY_HANDLER, func, sc->sc_dev);
215
216 return true;
217 }
218
219 void
220 acpicpu_pstate_callback(void *aux)
221 {
222 struct acpicpu_softc *sc;
223 device_t self = aux;
224 uint32_t old, new;
225
226 sc = device_private(self);
227
228 if ((sc->sc_flags & ACPICPU_FLAG_P_PPC) == 0)
229 return;
230
231 mutex_enter(&sc->sc_mtx);
232
233 old = sc->sc_pstate_max;
234 acpicpu_pstate_change(sc);
235 new = sc->sc_pstate_max;
236
237 mutex_exit(&sc->sc_mtx);
238
239 #if 0
240 if (old != new) {
241
242 /*
243 * If the maximum changed, proactively
244 * raise or lower the target frequency.
245 */
246 acpicpu_pstate_set(sc, sc->sc_pstate[new].ps_freq);
247
248 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "frequency changed from "
249 "%u MHz to %u MHz\n", sc->sc_pstate[old].ps_freq,
250 sc->sc_pstate[sc->sc_pstate_max].ps_freq));
251 }
252 #endif
253 }
254
255 ACPI_STATUS
256 acpicpu_pstate_pss(struct acpicpu_softc *sc)
257 {
258 struct acpicpu_pstate *ps;
259 ACPI_OBJECT *obj;
260 ACPI_BUFFER buf;
261 ACPI_STATUS rv;
262 uint32_t count;
263 uint32_t i, j;
264
265 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PSS", &buf);
266
267 if (ACPI_FAILURE(rv))
268 return rv;
269
270 obj = buf.Pointer;
271
272 if (obj->Type != ACPI_TYPE_PACKAGE) {
273 rv = AE_TYPE;
274 goto out;
275 }
276
277 sc->sc_pstate_count = obj->Package.Count;
278
279 if (sc->sc_pstate_count == 0) {
280 rv = AE_NOT_EXIST;
281 goto out;
282 }
283
284 if (sc->sc_pstate_count > ACPICPU_P_STATE_MAX) {
285 rv = AE_LIMIT;
286 goto out;
287 }
288
289 sc->sc_pstate = kmem_zalloc(sc->sc_pstate_count *
290 sizeof(struct acpicpu_pstate), KM_SLEEP);
291
292 if (sc->sc_pstate == NULL) {
293 rv = AE_NO_MEMORY;
294 goto out;
295 }
296
297 for (count = i = 0; i < sc->sc_pstate_count; i++) {
298
299 ps = &sc->sc_pstate[i];
300 rv = acpicpu_pstate_pss_add(ps, &obj->Package.Elements[i]);
301
302 if (ACPI_FAILURE(rv))
303 continue;
304
305 for (j = 0; j < i; j++) {
306
307 if (ps->ps_freq >= sc->sc_pstate[j].ps_freq) {
308 ps->ps_freq = 0;
309 break;
310 }
311 }
312
313 if (ps->ps_freq != 0)
314 count++;
315 }
316
317 rv = (count != 0) ? AE_OK : AE_NOT_EXIST;
318
319 out:
320 if (buf.Pointer != NULL)
321 ACPI_FREE(buf.Pointer);
322
323 return rv;
324 }
325
326 static ACPI_STATUS
327 acpicpu_pstate_pss_add(struct acpicpu_pstate *ps, ACPI_OBJECT *obj)
328 {
329 ACPI_OBJECT *elm;
330 uint32_t val[6];
331 uint32_t *p;
332 int i;
333
334 if (obj->Type != ACPI_TYPE_PACKAGE)
335 return AE_TYPE;
336
337 if (obj->Package.Count != 6)
338 return AE_BAD_DATA;
339
340 elm = obj->Package.Elements;
341
342 for (i = 0; i < 6; i++) {
343
344 if (elm[i].Type != ACPI_TYPE_INTEGER)
345 return AE_TYPE;
346
347 if (elm[i].Integer.Value > UINT32_MAX)
348 return AE_AML_NUMERIC_OVERFLOW;
349
350 val[i] = elm[i].Integer.Value;
351 }
352
353 if (val[0] == 0 || val[0] >= 0xFFFF)
354 return AE_BAD_DECIMAL_CONSTANT;
355
356 CTASSERT(sizeof(val) == sizeof(struct acpicpu_pstate) -
357 offsetof(struct acpicpu_pstate, ps_freq));
358
359 p = &ps->ps_freq;
360
361 for (i = 0; i < 6; i++, p++)
362 *p = val[i];
363
364 /*
365 * The latency is typically around 10 usec
366 * on Intel CPUs. Use that as the minimum.
367 */
368 if (ps->ps_latency < 10)
369 ps->ps_latency = 10;
370
371 return AE_OK;
372 }
373
374 ACPI_STATUS
375 acpicpu_pstate_pct(struct acpicpu_softc *sc)
376 {
377 static const size_t size = sizeof(struct acpicpu_reg);
378 struct acpicpu_reg *reg[2];
379 ACPI_OBJECT *elm, *obj;
380 ACPI_BUFFER buf;
381 ACPI_STATUS rv;
382 uint8_t width;
383 int i;
384
385 rv = acpi_eval_struct(sc->sc_node->ad_handle, "_PCT", &buf);
386
387 if (ACPI_FAILURE(rv))
388 return rv;
389
390 obj = buf.Pointer;
391
392 if (obj->Type != ACPI_TYPE_PACKAGE) {
393 rv = AE_TYPE;
394 goto out;
395 }
396
397 if (obj->Package.Count != 2) {
398 rv = AE_LIMIT;
399 goto out;
400 }
401
402 for (i = 0; i < 2; i++) {
403
404 elm = &obj->Package.Elements[i];
405
406 if (elm->Type != ACPI_TYPE_BUFFER) {
407 rv = AE_TYPE;
408 goto out;
409 }
410
411 if (size > elm->Buffer.Length) {
412 rv = AE_AML_BAD_RESOURCE_LENGTH;
413 goto out;
414 }
415
416 reg[i] = (struct acpicpu_reg *)elm->Buffer.Pointer;
417
418 switch (reg[i]->reg_spaceid) {
419
420 case ACPI_ADR_SPACE_SYSTEM_IO:
421
422 if (reg[i]->reg_addr == 0) {
423 rv = AE_AML_ILLEGAL_ADDRESS;
424 goto out;
425 }
426
427 width = reg[i]->reg_bitwidth;
428
429 if (width + reg[i]->reg_bitoffset > 32) {
430 rv = AE_AML_BAD_RESOURCE_VALUE;
431 goto out;
432 }
433
434 if (width != 8 && width != 16 && width != 32) {
435 rv = AE_AML_BAD_RESOURCE_VALUE;
436 goto out;
437 }
438
439 break;
440
441 case ACPI_ADR_SPACE_FIXED_HARDWARE:
442
443 if ((sc->sc_flags & ACPICPU_FLAG_P_FFH) == 0) {
444 rv = AE_SUPPORT;
445 goto out;
446 }
447
448 break;
449
450 default:
451 rv = AE_AML_INVALID_SPACE_ID;
452 goto out;
453 }
454 }
455
456 if (reg[0]->reg_spaceid != reg[1]->reg_spaceid) {
457 rv = AE_AML_INVALID_SPACE_ID;
458 goto out;
459 }
460
461 (void)memcpy(&sc->sc_pstate_control, reg[0], size); /* PERF_CTRL */
462 (void)memcpy(&sc->sc_pstate_status, reg[1], size); /* PERF_STATUS */
463
464 out:
465 if (buf.Pointer != NULL)
466 ACPI_FREE(buf.Pointer);
467
468 return rv;
469 }
470
471 static int
472 acpicpu_pstate_max(struct acpicpu_softc *sc)
473 {
474 ACPI_INTEGER val;
475 ACPI_STATUS rv;
476
477 /*
478 * Evaluate the currently highest P-state that can be used.
479 * If available, we can use either this state or any lower
480 * power (i.e. higher numbered) state from the _PSS object.
481 */
482 rv = acpi_eval_integer(sc->sc_node->ad_handle, "_PPC", &val);
483
484 sc->sc_pstate_max = 0;
485
486 if (ACPI_FAILURE(rv))
487 return 1;
488
489 if (val > (uint64_t)sc->sc_pstate_count)
490 return 1;
491
492 if (sc->sc_pstate[val].ps_freq == 0)
493 return 1;
494
495 sc->sc_pstate_max = val; /* XXX: sysctl(8) knob? */
496
497 return 0;
498 }
499
500 static void
501 acpicpu_pstate_change(struct acpicpu_softc *sc)
502 {
503 ACPI_OBJECT_LIST arg;
504 ACPI_OBJECT obj[2];
505
506 arg.Count = 2;
507 arg.Pointer = obj;
508
509 obj[0].Type = ACPI_TYPE_INTEGER;
510 obj[1].Type = ACPI_TYPE_INTEGER;
511
512 obj[0].Integer.Value = ACPICPU_P_NOTIFY;
513 obj[1].Integer.Value = acpicpu_pstate_max(sc);
514
515 (void)AcpiEvaluateObject(sc->sc_node->ad_handle, "_OST", &arg, NULL);
516 }
517
518 static void
519 acpicpu_pstate_bios(void)
520 {
521 const uint8_t val = AcpiGbl_FADT.PstateControl;
522 const uint32_t addr = AcpiGbl_FADT.SmiCommand;
523
524 if (addr == 0)
525 return;
526
527 (void)AcpiOsWritePort(addr, val, 8);
528 }
529
530 int
531 acpicpu_pstate_get(struct acpicpu_softc *sc, uint32_t *freq)
532 {
533 const uint8_t method = sc->sc_pstate_control.reg_spaceid;
534 struct acpicpu_pstate *ps = NULL;
535 uint32_t i, val = 0;
536 uint64_t addr;
537 uint8_t width;
538 int rv;
539
540 if (sc->sc_cold != false) {
541 rv = EBUSY;
542 goto fail;
543 }
544
545 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) {
546 rv = ENODEV;
547 goto fail;
548 }
549
550 if (sc->sc_pstate_current != ACPICPU_P_STATE_UNKNOWN) {
551 *freq = sc->sc_pstate_current;
552 return 0;
553 }
554
555 switch (method) {
556
557 case ACPI_ADR_SPACE_FIXED_HARDWARE:
558
559 rv = acpicpu_md_pstate_get(sc, freq);
560
561 if (rv != 0)
562 goto fail;
563
564 break;
565
566 case ACPI_ADR_SPACE_SYSTEM_IO:
567
568 addr = sc->sc_pstate_status.reg_addr;
569 width = sc->sc_pstate_status.reg_bitwidth;
570
571 (void)AcpiOsReadPort(addr, &val, width);
572
573 if (val == 0) {
574 rv = EIO;
575 goto fail;
576 }
577
578 mutex_enter(&sc->sc_mtx);
579
580 for (i = 0; i < sc->sc_pstate_count; i++) {
581
582 if (sc->sc_pstate[i].ps_freq == 0)
583 continue;
584
585 if (val == sc->sc_pstate[i].ps_status) {
586 ps = &sc->sc_pstate[i];
587 break;
588 }
589 }
590
591 mutex_exit(&sc->sc_mtx);
592
593 if (ps == NULL) {
594 rv = EIO;
595 goto fail;
596 }
597
598 *freq = ps->ps_freq;
599 break;
600
601 default:
602 rv = ENOTTY;
603 goto fail;
604 }
605
606 sc->sc_pstate_current = *freq;
607
608 return 0;
609
610 fail:
611 aprint_error_dev(sc->sc_dev, "failed "
612 "to get frequency (err %d)\n", rv);
613
614 *freq = sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN;
615
616 return rv;
617 }
618
619 int
620 acpicpu_pstate_set(struct acpicpu_softc *sc, uint32_t freq)
621 {
622 const uint8_t method = sc->sc_pstate_control.reg_spaceid;
623 struct acpicpu_pstate *ps = NULL;
624 uint32_t i, val;
625 uint64_t addr;
626 uint8_t width;
627 int rv;
628
629 if (sc->sc_cold != false) {
630 rv = EBUSY;
631 goto fail;
632 }
633
634 if ((sc->sc_flags & ACPICPU_FLAG_P) == 0) {
635 rv = ENODEV;
636 goto fail;
637 }
638
639 mutex_enter(&sc->sc_mtx);
640
641 for (i = sc->sc_pstate_max; i < sc->sc_pstate_count; i++) {
642
643 if (sc->sc_pstate[i].ps_freq == 0)
644 continue;
645
646 if (sc->sc_pstate[i].ps_freq == freq) {
647 ps = &sc->sc_pstate[i];
648 break;
649 }
650 }
651
652 mutex_exit(&sc->sc_mtx);
653
654 if (ps == NULL) {
655 rv = EINVAL;
656 goto fail;
657 }
658
659 switch (method) {
660
661 case ACPI_ADR_SPACE_FIXED_HARDWARE:
662
663 rv = acpicpu_md_pstate_set(ps);
664
665 if (rv != 0)
666 goto fail;
667
668 break;
669
670 case ACPI_ADR_SPACE_SYSTEM_IO:
671
672 addr = sc->sc_pstate_control.reg_addr;
673 width = sc->sc_pstate_control.reg_bitwidth;
674
675 (void)AcpiOsWritePort(addr, ps->ps_control, width);
676
677 addr = sc->sc_pstate_status.reg_addr;
678 width = sc->sc_pstate_status.reg_bitwidth;
679
680 /*
681 * Some systems take longer to respond
682 * than the reported worst-case latency.
683 */
684 for (i = val = 0; i < ACPICPU_P_STATE_RETRY; i++) {
685
686 (void)AcpiOsReadPort(addr, &val, width);
687
688 if (val == ps->ps_status)
689 break;
690
691 DELAY(ps->ps_latency);
692 }
693
694 if (i == ACPICPU_P_STATE_RETRY) {
695 rv = EAGAIN;
696 goto fail;
697 }
698
699 break;
700
701 default:
702 rv = ENOTTY;
703 goto fail;
704 }
705
706 ps->ps_evcnt.ev_count++;
707 sc->sc_pstate_current = freq;
708
709 return 0;
710
711 fail:
712 aprint_error_dev(sc->sc_dev, "failed to set "
713 "frequency to %u (err %d)\n", freq, rv);
714
715 sc->sc_pstate_current = ACPICPU_P_STATE_UNKNOWN;
716
717 return rv;
718 }
719