xref: /freebsd/sys/dev/acpica/acpi_perf.c (revision 3c5ba95ad12285ad37c182a4bfc1b240ec6d18a7)
1 /*-
2  * Copyright (c) 2003-2005 Nate Lawson (SDG)
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
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.
13  *
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
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_acpi.h"
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/proc.h>
34 #include <sys/sched.h>
35 #include <sys/bus.h>
36 #include <sys/cpu.h>
37 #include <sys/power.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/sbuf.h>
41 #include <sys/pcpu.h>
42 
43 #include <machine/bus.h>
44 #include <machine/resource.h>
45 #include <sys/rman.h>
46 
47 #include <contrib/dev/acpica/include/acpi.h>
48 
49 #include <dev/acpica/acpivar.h>
50 
51 #include "cpufreq_if.h"
52 
53 /*
54  * Support for ACPI processor performance states (Px) according to
55  * section 8.3.3 of the ACPI 2.0c specification.
56  */
57 
58 struct acpi_px {
59 	uint32_t	 core_freq;
60 	uint32_t	 power;
61 	uint32_t	 trans_lat;
62 	uint32_t	 bm_lat;
63 	uint32_t	 ctrl_val;
64 	uint32_t	 sts_val;
65 };
66 
67 /* Offsets in struct cf_setting array for storing driver-specific values. */
68 #define PX_SPEC_CONTROL	0
69 #define PX_SPEC_STATUS	1
70 
71 #define MAX_PX_STATES	16
72 
73 struct acpi_perf_softc {
74 	device_t	 dev;
75 	ACPI_HANDLE	 handle;
76 	struct resource	*perf_ctrl;	/* Set new performance state. */
77 	int		 perf_ctrl_type; /* Resource type for perf_ctrl. */
78 	struct resource	*perf_status;	/* Check that transition succeeded. */
79 	int		 perf_sts_type;	/* Resource type for perf_status. */
80 	struct acpi_px	*px_states;	/* ACPI perf states. */
81 	uint32_t	 px_count;	/* Total number of perf states. */
82 	uint32_t	 px_max_avail;	/* Lowest index state available. */
83 	int		 px_curr_state;	/* Active state index. */
84 	int		 px_rid;
85 	int		 info_only;	/* Can we set new states? */
86 };
87 
88 #define PX_GET_REG(reg) 				\
89 	(bus_space_read_4(rman_get_bustag((reg)), 	\
90 	    rman_get_bushandle((reg)), 0))
91 #define PX_SET_REG(reg, val)				\
92 	(bus_space_write_4(rman_get_bustag((reg)), 	\
93 	    rman_get_bushandle((reg)), 0, (val)))
94 
95 #define ACPI_NOTIFY_PERF_STATES		0x80	/* _PSS changed. */
96 
97 static void	acpi_perf_identify(driver_t *driver, device_t parent);
98 static int	acpi_perf_probe(device_t dev);
99 static int	acpi_perf_attach(device_t dev);
100 static int	acpi_perf_detach(device_t dev);
101 static int	acpi_perf_evaluate(device_t dev);
102 static int	acpi_px_to_set(device_t dev, struct acpi_px *px,
103 		    struct cf_setting *set);
104 static void	acpi_px_available(struct acpi_perf_softc *sc);
105 static void	acpi_px_startup(void *arg);
106 static void	acpi_px_notify(ACPI_HANDLE h, UINT32 notify, void *context);
107 static int	acpi_px_settings(device_t dev, struct cf_setting *sets,
108 		    int *count);
109 static int	acpi_px_set(device_t dev, const struct cf_setting *set);
110 static int	acpi_px_get(device_t dev, struct cf_setting *set);
111 static int	acpi_px_type(device_t dev, int *type);
112 
113 static device_method_t acpi_perf_methods[] = {
114 	/* Device interface */
115 	DEVMETHOD(device_identify,	acpi_perf_identify),
116 	DEVMETHOD(device_probe,		acpi_perf_probe),
117 	DEVMETHOD(device_attach,	acpi_perf_attach),
118 	DEVMETHOD(device_detach,	acpi_perf_detach),
119 
120 	/* cpufreq interface */
121 	DEVMETHOD(cpufreq_drv_set,	acpi_px_set),
122 	DEVMETHOD(cpufreq_drv_get,	acpi_px_get),
123 	DEVMETHOD(cpufreq_drv_type,	acpi_px_type),
124 	DEVMETHOD(cpufreq_drv_settings,	acpi_px_settings),
125 
126 	DEVMETHOD_END
127 };
128 
129 static driver_t acpi_perf_driver = {
130 	"acpi_perf",
131 	acpi_perf_methods,
132 	sizeof(struct acpi_perf_softc),
133 };
134 
135 static devclass_t acpi_perf_devclass;
136 DRIVER_MODULE(acpi_perf, cpu, acpi_perf_driver, acpi_perf_devclass, 0, 0);
137 MODULE_DEPEND(acpi_perf, acpi, 1, 1, 1);
138 
139 static MALLOC_DEFINE(M_ACPIPERF, "acpi_perf", "ACPI Performance states");
140 
141 static void
142 acpi_perf_identify(driver_t *driver, device_t parent)
143 {
144 	ACPI_HANDLE handle;
145 	device_t dev;
146 
147 	/* Make sure we're not being doubly invoked. */
148 	if (device_find_child(parent, "acpi_perf", -1) != NULL)
149 		return;
150 
151 	/* Get the handle for the Processor object and check for perf states. */
152 	handle = acpi_get_handle(parent);
153 	if (handle == NULL)
154 		return;
155 	if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PSS", NULL, NULL)))
156 		return;
157 
158 	/*
159 	 * Add a child to every CPU that has the right methods.  In future
160 	 * versions of the ACPI spec, CPUs can have different settings.
161 	 * We probe this child now so that other devices that depend
162 	 * on it (i.e., for info about supported states) will see it.
163 	 */
164 	if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_perf", -1)) != NULL)
165 		device_probe_and_attach(dev);
166 	else
167 		device_printf(parent, "add acpi_perf child failed\n");
168 }
169 
170 static int
171 acpi_perf_probe(device_t dev)
172 {
173 	ACPI_HANDLE handle;
174 	ACPI_OBJECT *pkg;
175 	struct resource *res;
176 	ACPI_BUFFER buf;
177 	int error, rid, type;
178 
179 	if (resource_disabled("acpi_perf", 0))
180 		return (ENXIO);
181 
182 	/*
183 	 * Check the performance state registers.  If they are of type
184 	 * "functional fixed hardware", we attach quietly since we will
185 	 * only be providing information on settings to other drivers.
186 	 */
187 	error = ENXIO;
188 	handle = acpi_get_handle(dev);
189 	buf.Pointer = NULL;
190 	buf.Length = ACPI_ALLOCATE_BUFFER;
191 	if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PCT", NULL, &buf)))
192 		return (error);
193 	pkg = (ACPI_OBJECT *)buf.Pointer;
194 	if (ACPI_PKG_VALID(pkg, 2)) {
195 		rid = 0;
196 		error = acpi_PkgGas(dev, pkg, 0, &type, &rid, &res, 0);
197 		switch (error) {
198 		case 0:
199 			bus_release_resource(dev, type, rid, res);
200 			bus_delete_resource(dev, type, rid);
201 			device_set_desc(dev, "ACPI CPU Frequency Control");
202 			break;
203 		case EOPNOTSUPP:
204 			device_quiet(dev);
205 			error = 0;
206 			break;
207 		}
208 	}
209 	AcpiOsFree(buf.Pointer);
210 
211 	return (error);
212 }
213 
214 static int
215 acpi_perf_attach(device_t dev)
216 {
217 	struct acpi_perf_softc *sc;
218 
219 	sc = device_get_softc(dev);
220 	sc->dev = dev;
221 	sc->handle = acpi_get_handle(dev);
222 	sc->px_max_avail = 0;
223 	sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
224 	if (acpi_perf_evaluate(dev) != 0)
225 		return (ENXIO);
226 	AcpiOsExecute(OSL_NOTIFY_HANDLER, acpi_px_startup, NULL);
227 	if (!sc->info_only)
228 		cpufreq_register(dev);
229 
230 	return (0);
231 }
232 
233 static int
234 acpi_perf_detach(device_t dev)
235 {
236 	/* TODO: teardown registers, remove notify handler. */
237 	return (ENXIO);
238 }
239 
240 /* Probe and setup any valid performance states (Px). */
241 static int
242 acpi_perf_evaluate(device_t dev)
243 {
244 	struct acpi_perf_softc *sc;
245 	ACPI_BUFFER buf;
246 	ACPI_OBJECT *pkg, *res;
247 	ACPI_STATUS status;
248 	int count, error, i, j;
249 	static int once = 1;
250 	uint32_t *p;
251 
252 	/* Get the control values and parameters for each state. */
253 	error = ENXIO;
254 	sc = device_get_softc(dev);
255 	buf.Pointer = NULL;
256 	buf.Length = ACPI_ALLOCATE_BUFFER;
257 	status = AcpiEvaluateObject(sc->handle, "_PSS", NULL, &buf);
258 	if (ACPI_FAILURE(status))
259 		return (ENXIO);
260 
261 	pkg = (ACPI_OBJECT *)buf.Pointer;
262 	if (!ACPI_PKG_VALID(pkg, 1)) {
263 		device_printf(dev, "invalid top level _PSS package\n");
264 		goto out;
265 	}
266 	sc->px_count = pkg->Package.Count;
267 
268 	sc->px_states = malloc(sc->px_count * sizeof(struct acpi_px),
269 	    M_ACPIPERF, M_WAITOK | M_ZERO);
270 
271 	/*
272 	 * Each state is a package of {CoreFreq, Power, TransitionLatency,
273 	 * BusMasterLatency, ControlVal, StatusVal}, sorted from highest
274 	 * performance to lowest.
275 	 */
276 	count = 0;
277 	for (i = 0; i < sc->px_count; i++) {
278 		res = &pkg->Package.Elements[i];
279 		if (!ACPI_PKG_VALID(res, 6)) {
280 			if (once) {
281 				once = 0;
282 				device_printf(dev, "invalid _PSS package\n");
283 			}
284 			continue;
285 		}
286 
287 		/* Parse the rest of the package into the struct. */
288 		p = &sc->px_states[count].core_freq;
289 		for (j = 0; j < 6; j++, p++)
290 			acpi_PkgInt32(res, j, p);
291 
292 		/*
293 		 * Check for some impossible frequencies that some systems
294 		 * use to indicate they don't actually support this Px state.
295 		 */
296 		if (sc->px_states[count].core_freq == 0 ||
297 		    sc->px_states[count].core_freq == 9999 ||
298 		    sc->px_states[count].core_freq == 0x9999 ||
299 		    sc->px_states[count].core_freq >= 0xffff)
300 			continue;
301 
302 		/* Check for duplicate entries */
303 		if (count > 0 &&
304 		    sc->px_states[count - 1].core_freq ==
305 			sc->px_states[count].core_freq)
306 			continue;
307 
308 		count++;
309 	}
310 	sc->px_count = count;
311 
312 	/* No valid Px state found so give up. */
313 	if (count == 0)
314 		goto out;
315 	AcpiOsFree(buf.Pointer);
316 
317 	/* Get the control and status registers (one of each). */
318 	buf.Pointer = NULL;
319 	buf.Length = ACPI_ALLOCATE_BUFFER;
320 	status = AcpiEvaluateObject(sc->handle, "_PCT", NULL, &buf);
321 	if (ACPI_FAILURE(status))
322 		goto out;
323 
324 	/* Check the package of two registers, each a Buffer in GAS format. */
325 	pkg = (ACPI_OBJECT *)buf.Pointer;
326 	if (!ACPI_PKG_VALID(pkg, 2)) {
327 		device_printf(dev, "invalid perf register package\n");
328 		goto out;
329 	}
330 
331 	error = acpi_PkgGas(sc->dev, pkg, 0, &sc->perf_ctrl_type, &sc->px_rid,
332 	    &sc->perf_ctrl, 0);
333 	if (error) {
334 		/*
335 		 * If the register is of type FFixedHW, we can only return
336 		 * info, we can't get or set new settings.
337 		 */
338 		if (error == EOPNOTSUPP) {
339 			sc->info_only = TRUE;
340 			error = 0;
341 		} else
342 			device_printf(dev, "failed in PERF_CTL attach\n");
343 		goto out;
344 	}
345 	sc->px_rid++;
346 
347 	error = acpi_PkgGas(sc->dev, pkg, 1, &sc->perf_sts_type, &sc->px_rid,
348 	    &sc->perf_status, 0);
349 	if (error) {
350 		if (error == EOPNOTSUPP) {
351 			sc->info_only = TRUE;
352 			error = 0;
353 		} else
354 			device_printf(dev, "failed in PERF_STATUS attach\n");
355 		goto out;
356 	}
357 	sc->px_rid++;
358 
359 	/* Get our current limit and register for notifies. */
360 	acpi_px_available(sc);
361 	AcpiInstallNotifyHandler(sc->handle, ACPI_DEVICE_NOTIFY,
362 	    acpi_px_notify, sc);
363 	error = 0;
364 
365 out:
366 	if (error) {
367 		if (sc->px_states) {
368 			free(sc->px_states, M_ACPIPERF);
369 			sc->px_states = NULL;
370 		}
371 		if (sc->perf_ctrl) {
372 			bus_release_resource(sc->dev, sc->perf_ctrl_type, 0,
373 			    sc->perf_ctrl);
374 			bus_delete_resource(sc->dev, sc->perf_ctrl_type, 0);
375 			sc->perf_ctrl = NULL;
376 		}
377 		if (sc->perf_status) {
378 			bus_release_resource(sc->dev, sc->perf_sts_type, 1,
379 			    sc->perf_status);
380 			bus_delete_resource(sc->dev, sc->perf_sts_type, 1);
381 			sc->perf_status = NULL;
382 		}
383 		sc->px_rid = 0;
384 		sc->px_count = 0;
385 	}
386 	if (buf.Pointer)
387 		AcpiOsFree(buf.Pointer);
388 	return (error);
389 }
390 
391 static void
392 acpi_px_startup(void *arg)
393 {
394 
395 	/* Signal to the platform that we are taking over CPU control. */
396 	if (AcpiGbl_FADT.PstateControl == 0)
397 		return;
398 	ACPI_LOCK(acpi);
399 	AcpiOsWritePort(AcpiGbl_FADT.SmiCommand, AcpiGbl_FADT.PstateControl, 8);
400 	ACPI_UNLOCK(acpi);
401 }
402 
403 static void
404 acpi_px_notify(ACPI_HANDLE h, UINT32 notify, void *context)
405 {
406 	struct acpi_perf_softc *sc;
407 
408 	sc = context;
409 	if (notify != ACPI_NOTIFY_PERF_STATES)
410 		return;
411 
412 	acpi_px_available(sc);
413 
414 	/* TODO: Implement notification when frequency changes. */
415 }
416 
417 /*
418  * Find the highest currently-supported performance state.
419  * This can be called at runtime (e.g., due to a docking event) at
420  * the request of a Notify on the processor object.
421  */
422 static void
423 acpi_px_available(struct acpi_perf_softc *sc)
424 {
425 	ACPI_STATUS status;
426 	struct cf_setting set;
427 
428 	status = acpi_GetInteger(sc->handle, "_PPC", &sc->px_max_avail);
429 
430 	/* If the old state is too high, set current state to the new max. */
431 	if (ACPI_SUCCESS(status)) {
432 		if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN &&
433 		    sc->px_curr_state > sc->px_max_avail) {
434 			acpi_px_to_set(sc->dev,
435 			    &sc->px_states[sc->px_max_avail], &set);
436 			acpi_px_set(sc->dev, &set);
437 		}
438 	} else
439 		sc->px_max_avail = 0;
440 }
441 
442 static int
443 acpi_px_to_set(device_t dev, struct acpi_px *px, struct cf_setting *set)
444 {
445 
446 	if (px == NULL || set == NULL)
447 		return (EINVAL);
448 
449 	set->freq = px->core_freq;
450 	set->power = px->power;
451 	/* XXX Include BM latency too? */
452 	set->lat = px->trans_lat;
453 	set->volts = CPUFREQ_VAL_UNKNOWN;
454 	set->dev = dev;
455 	set->spec[PX_SPEC_CONTROL] = px->ctrl_val;
456 	set->spec[PX_SPEC_STATUS] = px->sts_val;
457 
458 	return (0);
459 }
460 
461 static int
462 acpi_px_settings(device_t dev, struct cf_setting *sets, int *count)
463 {
464 	struct acpi_perf_softc *sc;
465 	int x, y;
466 
467 	sc = device_get_softc(dev);
468 	if (sets == NULL || count == NULL)
469 		return (EINVAL);
470 	if (*count < sc->px_count - sc->px_max_avail)
471 		return (E2BIG);
472 
473 	/* Return a list of settings that are currently valid. */
474 	y = 0;
475 	for (x = sc->px_max_avail; x < sc->px_count; x++, y++)
476 		acpi_px_to_set(dev, &sc->px_states[x], &sets[y]);
477 	*count = sc->px_count - sc->px_max_avail;
478 
479 	return (0);
480 }
481 
482 static int
483 acpi_px_set(device_t dev, const struct cf_setting *set)
484 {
485 	struct acpi_perf_softc *sc;
486 	int i, status, sts_val, tries;
487 
488 	if (set == NULL)
489 		return (EINVAL);
490 	sc = device_get_softc(dev);
491 
492 	/* If we can't set new states, return immediately. */
493 	if (sc->info_only)
494 		return (ENXIO);
495 
496 	/* Look up appropriate state, based on frequency. */
497 	for (i = sc->px_max_avail; i < sc->px_count; i++) {
498 		if (CPUFREQ_CMP(set->freq, sc->px_states[i].core_freq))
499 			break;
500 	}
501 	if (i == sc->px_count)
502 		return (EINVAL);
503 
504 	/* Write the appropriate value to the register. */
505 	PX_SET_REG(sc->perf_ctrl, sc->px_states[i].ctrl_val);
506 
507 	/*
508 	 * Try for up to 10 ms to verify the desired state was selected.
509 	 * This is longer than the standard says (1 ms) but in some modes,
510 	 * systems may take longer to respond.
511 	 */
512 	sts_val = sc->px_states[i].sts_val;
513 	for (tries = 0; tries < 1000; tries++) {
514 		status = PX_GET_REG(sc->perf_status);
515 
516 		/*
517 		 * If we match the status or the desired status is 8 bits
518 		 * and matches the relevant bits, assume we succeeded.  It
519 		 * appears some systems (IBM R32) expect byte-wide access
520 		 * even though the standard says the register is 32-bit.
521 		 */
522 		if (status == sts_val ||
523 		    ((sts_val & ~0xff) == 0 && (status & 0xff) == sts_val))
524 			break;
525 		DELAY(10);
526 	}
527 	if (tries == 1000) {
528 		device_printf(dev, "Px transition to %d failed\n",
529 		    sc->px_states[i].core_freq);
530 		return (ENXIO);
531 	}
532 	sc->px_curr_state = i;
533 
534 	return (0);
535 }
536 
537 static int
538 acpi_px_get(device_t dev, struct cf_setting *set)
539 {
540 	struct acpi_perf_softc *sc;
541 	uint64_t rate;
542 	int i;
543 	struct pcpu *pc;
544 
545 	if (set == NULL)
546 		return (EINVAL);
547 	sc = device_get_softc(dev);
548 
549 	/* If we can't get new states, return immediately. */
550 	if (sc->info_only)
551 		return (ENXIO);
552 
553 	/* If we've set the rate before, use the cached value. */
554 	if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN) {
555 		acpi_px_to_set(dev, &sc->px_states[sc->px_curr_state], set);
556 		return (0);
557 	}
558 
559 	/* Otherwise, estimate and try to match against our settings. */
560 	pc = cpu_get_pcpu(dev);
561 	if (pc == NULL)
562 		return (ENXIO);
563 	cpu_est_clockrate(pc->pc_cpuid, &rate);
564 	rate /= 1000000;
565 	for (i = 0; i < sc->px_count; i++) {
566 		if (CPUFREQ_CMP(sc->px_states[i].core_freq, rate)) {
567 			sc->px_curr_state = i;
568 			acpi_px_to_set(dev, &sc->px_states[i], set);
569 			break;
570 		}
571 	}
572 
573 	/* No match, give up. */
574 	if (i == sc->px_count) {
575 		sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
576 		set->freq = CPUFREQ_VAL_UNKNOWN;
577 	}
578 
579 	return (0);
580 }
581 
582 static int
583 acpi_px_type(device_t dev, int *type)
584 {
585 	struct acpi_perf_softc *sc;
586 
587 	if (type == NULL)
588 		return (EINVAL);
589 	sc = device_get_softc(dev);
590 
591 	*type = CPUFREQ_TYPE_ABSOLUTE;
592 	if (sc->info_only)
593 		*type |= CPUFREQ_FLAG_INFO_ONLY;
594 	return (0);
595 }
596