xref: /freebsd/sys/dev/acpica/acpi_perf.c (revision 1670a1c2a47d10ecccd001970b859caf93cd3b6e)
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 	{0, 0}
126 };
127 
128 static driver_t acpi_perf_driver = {
129 	"acpi_perf",
130 	acpi_perf_methods,
131 	sizeof(struct acpi_perf_softc),
132 };
133 
134 static devclass_t acpi_perf_devclass;
135 DRIVER_MODULE(acpi_perf, cpu, acpi_perf_driver, acpi_perf_devclass, 0, 0);
136 MODULE_DEPEND(acpi_perf, acpi, 1, 1, 1);
137 
138 MALLOC_DEFINE(M_ACPIPERF, "acpi_perf", "ACPI Performance states");
139 
140 static void
141 acpi_perf_identify(driver_t *driver, device_t parent)
142 {
143 	ACPI_HANDLE handle;
144 	device_t dev;
145 
146 	/* Make sure we're not being doubly invoked. */
147 	if (device_find_child(parent, "acpi_perf", -1) != NULL)
148 		return;
149 
150 	/* Get the handle for the Processor object and check for perf states. */
151 	handle = acpi_get_handle(parent);
152 	if (handle == NULL)
153 		return;
154 	if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PSS", NULL, NULL)))
155 		return;
156 
157 	/*
158 	 * Add a child to every CPU that has the right methods.  In future
159 	 * versions of the ACPI spec, CPUs can have different settings.
160 	 * We probe this child now so that other devices that depend
161 	 * on it (i.e., for info about supported states) will see it.
162 	 */
163 	if ((dev = BUS_ADD_CHILD(parent, 0, "acpi_perf", -1)) != NULL)
164 		device_probe_and_attach(dev);
165 	else
166 		device_printf(parent, "add acpi_perf child failed\n");
167 }
168 
169 static int
170 acpi_perf_probe(device_t dev)
171 {
172 	ACPI_HANDLE handle;
173 	ACPI_OBJECT *pkg;
174 	struct resource *res;
175 	ACPI_BUFFER buf;
176 	int error, rid, type;
177 
178 	if (resource_disabled("acpi_perf", 0))
179 		return (ENXIO);
180 
181 	/*
182 	 * Check the performance state registers.  If they are of type
183 	 * "functional fixed hardware", we attach quietly since we will
184 	 * only be providing information on settings to other drivers.
185 	 */
186 	error = ENXIO;
187 	handle = acpi_get_handle(dev);
188 	buf.Pointer = NULL;
189 	buf.Length = ACPI_ALLOCATE_BUFFER;
190 	if (ACPI_FAILURE(AcpiEvaluateObject(handle, "_PCT", NULL, &buf)))
191 		return (error);
192 	pkg = (ACPI_OBJECT *)buf.Pointer;
193 	if (ACPI_PKG_VALID(pkg, 2)) {
194 		rid = 0;
195 		error = acpi_PkgGas(dev, pkg, 0, &type, &rid, &res, 0);
196 		switch (error) {
197 		case 0:
198 			bus_release_resource(dev, type, rid, res);
199 			bus_delete_resource(dev, type, rid);
200 			device_set_desc(dev, "ACPI CPU Frequency Control");
201 			break;
202 		case EOPNOTSUPP:
203 			device_quiet(dev);
204 			error = 0;
205 			break;
206 		}
207 	}
208 	AcpiOsFree(buf.Pointer);
209 
210 	return (error);
211 }
212 
213 static int
214 acpi_perf_attach(device_t dev)
215 {
216 	struct acpi_perf_softc *sc;
217 
218 	sc = device_get_softc(dev);
219 	sc->dev = dev;
220 	sc->handle = acpi_get_handle(dev);
221 	sc->px_max_avail = 0;
222 	sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
223 	if (acpi_perf_evaluate(dev) != 0)
224 		return (ENXIO);
225 	AcpiOsExecute(OSL_NOTIFY_HANDLER, acpi_px_startup, NULL);
226 	if (!sc->info_only)
227 		cpufreq_register(dev);
228 
229 	return (0);
230 }
231 
232 static int
233 acpi_perf_detach(device_t dev)
234 {
235 	/* TODO: teardown registers, remove notify handler. */
236 	return (ENXIO);
237 }
238 
239 /* Probe and setup any valid performance states (Px). */
240 static int
241 acpi_perf_evaluate(device_t dev)
242 {
243 	struct acpi_perf_softc *sc;
244 	ACPI_BUFFER buf;
245 	ACPI_OBJECT *pkg, *res;
246 	ACPI_STATUS status;
247 	int count, error, i, j;
248 	static int once = 1;
249 	uint32_t *p;
250 
251 	/* Get the control values and parameters for each state. */
252 	error = ENXIO;
253 	sc = device_get_softc(dev);
254 	buf.Pointer = NULL;
255 	buf.Length = ACPI_ALLOCATE_BUFFER;
256 	status = AcpiEvaluateObject(sc->handle, "_PSS", NULL, &buf);
257 	if (ACPI_FAILURE(status))
258 		return (ENXIO);
259 
260 	pkg = (ACPI_OBJECT *)buf.Pointer;
261 	if (!ACPI_PKG_VALID(pkg, 1)) {
262 		device_printf(dev, "invalid top level _PSS package\n");
263 		goto out;
264 	}
265 	sc->px_count = pkg->Package.Count;
266 
267 	sc->px_states = malloc(sc->px_count * sizeof(struct acpi_px),
268 	    M_ACPIPERF, M_WAITOK | M_ZERO);
269 	if (sc->px_states == NULL)
270 		goto out;
271 
272 	/*
273 	 * Each state is a package of {CoreFreq, Power, TransitionLatency,
274 	 * BusMasterLatency, ControlVal, StatusVal}, sorted from highest
275 	 * performance to lowest.
276 	 */
277 	count = 0;
278 	for (i = 0; i < sc->px_count; i++) {
279 		res = &pkg->Package.Elements[i];
280 		if (!ACPI_PKG_VALID(res, 6)) {
281 			if (once) {
282 				once = 0;
283 				device_printf(dev, "invalid _PSS package\n");
284 			}
285 			continue;
286 		}
287 
288 		/* Parse the rest of the package into the struct. */
289 		p = &sc->px_states[count].core_freq;
290 		for (j = 0; j < 6; j++, p++)
291 			acpi_PkgInt32(res, j, p);
292 
293 		/*
294 		 * Check for some impossible frequencies that some systems
295 		 * use to indicate they don't actually support this Px state.
296 		 */
297 		if (sc->px_states[count].core_freq == 0 ||
298 		    sc->px_states[count].core_freq == 9999 ||
299 		    sc->px_states[count].core_freq == 0x9999 ||
300 		    sc->px_states[count].core_freq >= 0xffff)
301 			continue;
302 
303 		/* Check for duplicate entries */
304 		if (count > 0 &&
305 		    sc->px_states[count - 1].core_freq ==
306 			sc->px_states[count].core_freq)
307 			continue;
308 
309 		count++;
310 	}
311 	sc->px_count = count;
312 
313 	/* No valid Px state found so give up. */
314 	if (count == 0)
315 		goto out;
316 	AcpiOsFree(buf.Pointer);
317 
318 	/* Get the control and status registers (one of each). */
319 	buf.Pointer = NULL;
320 	buf.Length = ACPI_ALLOCATE_BUFFER;
321 	status = AcpiEvaluateObject(sc->handle, "_PCT", NULL, &buf);
322 	if (ACPI_FAILURE(status))
323 		goto out;
324 
325 	/* Check the package of two registers, each a Buffer in GAS format. */
326 	pkg = (ACPI_OBJECT *)buf.Pointer;
327 	if (!ACPI_PKG_VALID(pkg, 2)) {
328 		device_printf(dev, "invalid perf register package\n");
329 		goto out;
330 	}
331 
332 	error = acpi_PkgGas(sc->dev, pkg, 0, &sc->perf_ctrl_type, &sc->px_rid,
333 	    &sc->perf_ctrl, 0);
334 	if (error) {
335 		/*
336 		 * If the register is of type FFixedHW, we can only return
337 		 * info, we can't get or set new settings.
338 		 */
339 		if (error == EOPNOTSUPP) {
340 			sc->info_only = TRUE;
341 			error = 0;
342 		} else
343 			device_printf(dev, "failed in PERF_CTL attach\n");
344 		goto out;
345 	}
346 	sc->px_rid++;
347 
348 	error = acpi_PkgGas(sc->dev, pkg, 1, &sc->perf_sts_type, &sc->px_rid,
349 	    &sc->perf_status, 0);
350 	if (error) {
351 		if (error == EOPNOTSUPP) {
352 			sc->info_only = TRUE;
353 			error = 0;
354 		} else
355 			device_printf(dev, "failed in PERF_STATUS attach\n");
356 		goto out;
357 	}
358 	sc->px_rid++;
359 
360 	/* Get our current limit and register for notifies. */
361 	acpi_px_available(sc);
362 	AcpiInstallNotifyHandler(sc->handle, ACPI_DEVICE_NOTIFY,
363 	    acpi_px_notify, sc);
364 	error = 0;
365 
366 out:
367 	if (error) {
368 		if (sc->px_states) {
369 			free(sc->px_states, M_ACPIPERF);
370 			sc->px_states = NULL;
371 		}
372 		if (sc->perf_ctrl) {
373 			bus_release_resource(sc->dev, sc->perf_ctrl_type, 0,
374 			    sc->perf_ctrl);
375 			bus_delete_resource(sc->dev, sc->perf_ctrl_type, 0);
376 			sc->perf_ctrl = NULL;
377 		}
378 		if (sc->perf_status) {
379 			bus_release_resource(sc->dev, sc->perf_sts_type, 1,
380 			    sc->perf_status);
381 			bus_delete_resource(sc->dev, sc->perf_sts_type, 1);
382 			sc->perf_status = NULL;
383 		}
384 		sc->px_rid = 0;
385 		sc->px_count = 0;
386 	}
387 	if (buf.Pointer)
388 		AcpiOsFree(buf.Pointer);
389 	return (error);
390 }
391 
392 static void
393 acpi_px_startup(void *arg)
394 {
395 
396 	/* Signal to the platform that we are taking over CPU control. */
397 	if (AcpiGbl_FADT.PstateControl == 0)
398 		return;
399 	ACPI_LOCK(acpi);
400 	AcpiOsWritePort(AcpiGbl_FADT.SmiCommand, AcpiGbl_FADT.PstateControl, 8);
401 	ACPI_UNLOCK(acpi);
402 }
403 
404 static void
405 acpi_px_notify(ACPI_HANDLE h, UINT32 notify, void *context)
406 {
407 	struct acpi_perf_softc *sc;
408 
409 	sc = context;
410 	if (notify != ACPI_NOTIFY_PERF_STATES)
411 		return;
412 
413 	acpi_px_available(sc);
414 
415 	/* TODO: Implement notification when frequency changes. */
416 }
417 
418 /*
419  * Find the highest currently-supported performance state.
420  * This can be called at runtime (e.g., due to a docking event) at
421  * the request of a Notify on the processor object.
422  */
423 static void
424 acpi_px_available(struct acpi_perf_softc *sc)
425 {
426 	ACPI_STATUS status;
427 	struct cf_setting set;
428 
429 	status = acpi_GetInteger(sc->handle, "_PPC", &sc->px_max_avail);
430 
431 	/* If the old state is too high, set current state to the new max. */
432 	if (ACPI_SUCCESS(status)) {
433 		if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN &&
434 		    sc->px_curr_state > sc->px_max_avail) {
435 			acpi_px_to_set(sc->dev,
436 			    &sc->px_states[sc->px_max_avail], &set);
437 			acpi_px_set(sc->dev, &set);
438 		}
439 	} else
440 		sc->px_max_avail = 0;
441 }
442 
443 static int
444 acpi_px_to_set(device_t dev, struct acpi_px *px, struct cf_setting *set)
445 {
446 
447 	if (px == NULL || set == NULL)
448 		return (EINVAL);
449 
450 	set->freq = px->core_freq;
451 	set->power = px->power;
452 	/* XXX Include BM latency too? */
453 	set->lat = px->trans_lat;
454 	set->volts = CPUFREQ_VAL_UNKNOWN;
455 	set->dev = dev;
456 	set->spec[PX_SPEC_CONTROL] = px->ctrl_val;
457 	set->spec[PX_SPEC_STATUS] = px->sts_val;
458 
459 	return (0);
460 }
461 
462 static int
463 acpi_px_settings(device_t dev, struct cf_setting *sets, int *count)
464 {
465 	struct acpi_perf_softc *sc;
466 	int x, y;
467 
468 	sc = device_get_softc(dev);
469 	if (sets == NULL || count == NULL)
470 		return (EINVAL);
471 	if (*count < sc->px_count - sc->px_max_avail)
472 		return (E2BIG);
473 
474 	/* Return a list of settings that are currently valid. */
475 	y = 0;
476 	for (x = sc->px_max_avail; x < sc->px_count; x++, y++)
477 		acpi_px_to_set(dev, &sc->px_states[x], &sets[y]);
478 	*count = sc->px_count - sc->px_max_avail;
479 
480 	return (0);
481 }
482 
483 static int
484 acpi_px_set(device_t dev, const struct cf_setting *set)
485 {
486 	struct acpi_perf_softc *sc;
487 	int i, status, sts_val, tries;
488 
489 	if (set == NULL)
490 		return (EINVAL);
491 	sc = device_get_softc(dev);
492 
493 	/* If we can't set new states, return immediately. */
494 	if (sc->info_only)
495 		return (ENXIO);
496 
497 	/* Look up appropriate state, based on frequency. */
498 	for (i = sc->px_max_avail; i < sc->px_count; i++) {
499 		if (CPUFREQ_CMP(set->freq, sc->px_states[i].core_freq))
500 			break;
501 	}
502 	if (i == sc->px_count)
503 		return (EINVAL);
504 
505 	/* Write the appropriate value to the register. */
506 	PX_SET_REG(sc->perf_ctrl, sc->px_states[i].ctrl_val);
507 
508 	/*
509 	 * Try for up to 10 ms to verify the desired state was selected.
510 	 * This is longer than the standard says (1 ms) but in some modes,
511 	 * systems may take longer to respond.
512 	 */
513 	sts_val = sc->px_states[i].sts_val;
514 	for (tries = 0; tries < 1000; tries++) {
515 		status = PX_GET_REG(sc->perf_status);
516 
517 		/*
518 		 * If we match the status or the desired status is 8 bits
519 		 * and matches the relevant bits, assume we succeeded.  It
520 		 * appears some systems (IBM R32) expect byte-wide access
521 		 * even though the standard says the register is 32-bit.
522 		 */
523 		if (status == sts_val ||
524 		    ((sts_val & ~0xff) == 0 && (status & 0xff) == sts_val))
525 			break;
526 		DELAY(10);
527 	}
528 	if (tries == 1000) {
529 		device_printf(dev, "Px transition to %d failed\n",
530 		    sc->px_states[i].core_freq);
531 		return (ENXIO);
532 	}
533 	sc->px_curr_state = i;
534 
535 	return (0);
536 }
537 
538 static int
539 acpi_px_get(device_t dev, struct cf_setting *set)
540 {
541 	struct acpi_perf_softc *sc;
542 	uint64_t rate;
543 	int i;
544 	struct pcpu *pc;
545 
546 	if (set == NULL)
547 		return (EINVAL);
548 	sc = device_get_softc(dev);
549 
550 	/* If we can't get new states, return immediately. */
551 	if (sc->info_only)
552 		return (ENXIO);
553 
554 	/* If we've set the rate before, use the cached value. */
555 	if (sc->px_curr_state != CPUFREQ_VAL_UNKNOWN) {
556 		acpi_px_to_set(dev, &sc->px_states[sc->px_curr_state], set);
557 		return (0);
558 	}
559 
560 	/* Otherwise, estimate and try to match against our settings. */
561 	pc = cpu_get_pcpu(dev);
562 	if (pc == NULL)
563 		return (ENXIO);
564 	cpu_est_clockrate(pc->pc_cpuid, &rate);
565 	rate /= 1000000;
566 	for (i = 0; i < sc->px_count; i++) {
567 		if (CPUFREQ_CMP(sc->px_states[i].core_freq, rate)) {
568 			sc->px_curr_state = i;
569 			acpi_px_to_set(dev, &sc->px_states[i], set);
570 			break;
571 		}
572 	}
573 
574 	/* No match, give up. */
575 	if (i == sc->px_count) {
576 		sc->px_curr_state = CPUFREQ_VAL_UNKNOWN;
577 		set->freq = CPUFREQ_VAL_UNKNOWN;
578 	}
579 
580 	return (0);
581 }
582 
583 static int
584 acpi_px_type(device_t dev, int *type)
585 {
586 	struct acpi_perf_softc *sc;
587 
588 	if (type == NULL)
589 		return (EINVAL);
590 	sc = device_get_softc(dev);
591 
592 	*type = CPUFREQ_TYPE_ABSOLUTE;
593 	if (sc->info_only)
594 		*type |= CPUFREQ_FLAG_INFO_ONLY;
595 	return (0);
596 }
597