xref: /freebsd/sys/dev/psci/psci.c (revision 7fc95c31f007ef01c53aa5f9d8802e9579f408ee)
1 /*-
2  * Copyright (c) 2014 Robin Randhawa
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 
28 /*
29  * This implements support for ARM's Power State Co-ordination Interface
30  * [PSCI]. The implementation adheres to version 0.2 of the PSCI specification
31  * but also supports v0.1. PSCI standardizes operations such as system reset, CPU
32  * on/off/suspend. PSCI requires a compliant firmware implementation.
33  *
34  * The PSCI specification used for this implementation is available at:
35  *
36  * <http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0022b/index.html>.
37  *
38  * TODO:
39  * - Add support for remaining PSCI calls [this implementation only
40  *   supports get_version, system_reset and cpu_on].
41  */
42 
43 #include <sys/cdefs.h>
44 #include "opt_acpi.h"
45 #include "opt_platform.h"
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/bus.h>
50 #include <sys/eventhandler.h>
51 #include <sys/kernel.h>
52 #include <sys/module.h>
53 #include <sys/reboot.h>
54 
55 #include <machine/bus.h>
56 #include <machine/machdep.h>
57 
58 #ifdef DEV_ACPI
59 #include <contrib/dev/acpica/include/acpi.h>
60 #include <dev/acpica/acpivar.h>
61 #endif
62 
63 #ifdef FDT
64 #include <dev/fdt/fdt_common.h>
65 #include <dev/ofw/openfirm.h>
66 #include <dev/ofw/ofw_bus.h>
67 #include <dev/ofw/ofw_bus_subr.h>
68 #endif
69 
70 #include <dev/psci/psci.h>
71 
72 struct psci_softc {
73 	device_t        dev;
74 
75 	uint32_t	psci_version;
76 	uint32_t	psci_fnids[PSCI_FN_MAX];
77 };
78 
79 #ifdef FDT
80 static int psci_v0_1_init(device_t dev, int default_version);
81 #endif
82 static int psci_v0_2_init(device_t dev, int default_version);
83 
84 struct psci_softc *psci_softc = NULL;
85 bool psci_present;
86 
87 #ifdef __arm__
88 #define	USE_ACPI	0
89 #define	USE_FDT		1
90 #elif defined(__aarch64__)
91 #define	USE_ACPI	(arm64_bus_method == ARM64_BUS_ACPI)
92 #define	USE_FDT		(arm64_bus_method == ARM64_BUS_FDT)
93 #else
94 #error Unknown architecture
95 #endif
96 
97 #ifdef FDT
98 struct psci_init_def {
99 	int		default_version;
100 	psci_initfn_t	psci_init;
101 };
102 
103 static struct psci_init_def psci_v1_0_init_def = {
104 	.default_version = (1 << 16) | 0,
105 	.psci_init = psci_v0_2_init
106 };
107 
108 static struct psci_init_def psci_v0_2_init_def = {
109 	.default_version = (0 << 16) | 2,
110 	.psci_init = psci_v0_2_init
111 };
112 
113 static struct psci_init_def psci_v0_1_init_def = {
114 	.default_version = (0 << 16) | 1,
115 	.psci_init = psci_v0_1_init
116 };
117 
118 static struct ofw_compat_data compat_data[] = {
119 	{"arm,psci-1.0",        (uintptr_t)&psci_v1_0_init_def},
120 	{"arm,psci-0.2",        (uintptr_t)&psci_v0_2_init_def},
121 	{"arm,psci",            (uintptr_t)&psci_v0_1_init_def},
122 	{NULL,                  0}
123 };
124 #endif
125 
126 static int psci_attach(device_t, psci_initfn_t, int);
127 static void psci_shutdown(void *, int);
128 
129 static int psci_find_callfn(psci_callfn_t *);
130 static int psci_def_callfn(register_t, register_t, register_t, register_t,
131 	register_t, register_t, register_t, register_t,
132 	struct arm_smccc_res *res);
133 
134 psci_callfn_t psci_callfn = psci_def_callfn;
135 
136 static void
137 psci_init(void *dummy)
138 {
139 	psci_callfn_t new_callfn;
140 
141 	if (psci_find_callfn(&new_callfn) != PSCI_RETVAL_SUCCESS) {
142 		printf("No PSCI/SMCCC call function found\n");
143 		return;
144 	}
145 
146 	psci_callfn = new_callfn;
147 	psci_present = true;
148 }
149 /* This needs to be before cpu_mp at SI_SUB_CPU, SI_ORDER_THIRD */
150 SYSINIT(psci_start, SI_SUB_CPU, SI_ORDER_FIRST, psci_init, NULL);
151 
152 static int
153 psci_def_callfn(register_t a __unused, register_t b __unused,
154     register_t c __unused, register_t d __unused,
155     register_t e __unused, register_t f __unused,
156     register_t g __unused, register_t h __unused,
157     struct arm_smccc_res *res __unused)
158 {
159 
160 	panic("No PSCI/SMCCC call function set");
161 }
162 
163 #ifdef FDT
164 static int psci_fdt_probe(device_t dev);
165 static int psci_fdt_attach(device_t dev);
166 
167 static device_method_t psci_fdt_methods[] = {
168 	DEVMETHOD(device_probe,     psci_fdt_probe),
169 	DEVMETHOD(device_attach,    psci_fdt_attach),
170 
171 	DEVMETHOD_END
172 };
173 
174 static driver_t psci_fdt_driver = {
175 	"psci",
176 	psci_fdt_methods,
177 	sizeof(struct psci_softc),
178 };
179 
180 EARLY_DRIVER_MODULE(psci, simplebus, psci_fdt_driver, 0, 0,
181     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
182 EARLY_DRIVER_MODULE(psci, ofwbus, psci_fdt_driver, 0, 0,
183     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
184 
185 static psci_callfn_t
186 psci_fdt_get_callfn(phandle_t node)
187 {
188 	char method[16];
189 
190 	if ((OF_getprop(node, "method", method, sizeof(method))) > 0) {
191 		if (strcmp(method, "hvc") == 0)
192 			return (arm_smccc_hvc);
193 		else if (strcmp(method, "smc") == 0)
194 			return (arm_smccc_smc);
195 		else
196 			printf("psci: PSCI conduit \"%s\" invalid\n", method);
197 	} else
198 		printf("psci: PSCI conduit not supplied in the device tree\n");
199 
200 	return (NULL);
201 }
202 
203 static int
204 psci_fdt_probe(device_t dev)
205 {
206 	const struct ofw_compat_data *ocd;
207 
208 	if (!ofw_bus_status_okay(dev))
209 		return (ENXIO);
210 
211 	ocd = ofw_bus_search_compatible(dev, compat_data);
212 	if (ocd->ocd_str == NULL)
213 		return (ENXIO);
214 
215 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
216 
217 	return (BUS_PROBE_SPECIFIC);
218 }
219 
220 static int
221 psci_fdt_attach(device_t dev)
222 {
223 	const struct ofw_compat_data *ocd;
224 	struct psci_init_def *psci_init_def;
225 
226 	ocd = ofw_bus_search_compatible(dev, compat_data);
227 	psci_init_def = (struct psci_init_def *)ocd->ocd_data;
228 
229 	return (psci_attach(dev, psci_init_def->psci_init,
230 	    psci_init_def->default_version));
231 }
232 #endif
233 
234 #ifdef DEV_ACPI
235 static void psci_acpi_identify(driver_t *, device_t);
236 static int psci_acpi_probe(device_t);
237 static int psci_acpi_attach(device_t);
238 
239 static device_method_t psci_acpi_methods[] = {
240 	/* Device interface */
241 	DEVMETHOD(device_identify,	psci_acpi_identify),
242 	DEVMETHOD(device_probe,		psci_acpi_probe),
243 	DEVMETHOD(device_attach,	psci_acpi_attach),
244 
245 	DEVMETHOD_END
246 };
247 
248 static driver_t psci_acpi_driver = {
249 	"psci",
250 	psci_acpi_methods,
251 	sizeof(struct psci_softc),
252 };
253 
254 EARLY_DRIVER_MODULE(psci, acpi, psci_acpi_driver, 0, 0,
255     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
256 
257 static int
258 psci_acpi_bootflags(void)
259 {
260 	ACPI_TABLE_FADT *fadt;
261 	vm_paddr_t physaddr;
262 	int flags;
263 
264 	physaddr = acpi_find_table(ACPI_SIG_FADT);
265 	if (physaddr == 0)
266 		return (0);
267 
268 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
269 	if (fadt == NULL) {
270 		printf("psci: Unable to map the FADT\n");
271 		return (0);
272 	}
273 
274 	flags = fadt->ArmBootFlags;
275 
276 	acpi_unmap_table(fadt);
277 	return (flags);
278 }
279 
280 static psci_callfn_t
281 psci_acpi_get_callfn(int flags)
282 {
283 
284 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
285 		if ((flags & ACPI_FADT_PSCI_USE_HVC) != 0)
286 			return (arm_smccc_hvc);
287 		else
288 			return (arm_smccc_smc);
289 	} else {
290 		printf("psci: PSCI conduit not supplied in the device tree\n");
291 	}
292 
293 	return (NULL);
294 }
295 
296 static void
297 psci_acpi_identify(driver_t *driver, device_t parent)
298 {
299 	device_t dev;
300 	int flags;
301 
302 	flags = psci_acpi_bootflags();
303 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
304 		dev = BUS_ADD_CHILD(parent,
305 		    BUS_PASS_CPU + BUS_PASS_ORDER_FIRST, "psci", -1);
306 
307 		if (dev != NULL)
308 			acpi_set_private(dev, (void *)(uintptr_t)flags);
309 	}
310 }
311 
312 static int
313 psci_acpi_probe(device_t dev)
314 {
315 	uintptr_t flags;
316 
317 	flags = (uintptr_t)acpi_get_private(dev);
318 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
319 		return (ENXIO);
320 
321 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
322 	return (BUS_PROBE_SPECIFIC);
323 }
324 
325 static int
326 psci_acpi_attach(device_t dev)
327 {
328 
329 	return (psci_attach(dev, psci_v0_2_init, PSCI_RETVAL_NOT_SUPPORTED));
330 }
331 #endif
332 
333 static int
334 psci_attach(device_t dev, psci_initfn_t psci_init, int default_version)
335 {
336 	struct psci_softc *sc = device_get_softc(dev);
337 
338 	if (psci_softc != NULL)
339 		return (ENXIO);
340 
341 	KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL"));
342 	if (psci_init(dev, default_version))
343 		return (ENXIO);
344 
345 #ifdef __aarch64__
346 	smccc_init();
347 #endif
348 
349 	psci_softc = sc;
350 
351 	return (0);
352 }
353 
354 static int
355 _psci_get_version(struct psci_softc *sc)
356 {
357 	uint32_t fnid;
358 
359 	/* PSCI version wasn't supported in v0.1. */
360 	fnid = sc->psci_fnids[PSCI_FN_VERSION];
361 	if (fnid)
362 		return (psci_call(fnid, 0, 0, 0));
363 
364 	return (PSCI_RETVAL_NOT_SUPPORTED);
365 }
366 
367 int
368 psci_get_version(void)
369 {
370 
371 	if (psci_softc == NULL)
372 		return (PSCI_RETVAL_NOT_SUPPORTED);
373 	return (_psci_get_version(psci_softc));
374 }
375 
376 #ifdef FDT
377 static int
378 psci_fdt_callfn(psci_callfn_t *callfn)
379 {
380 	phandle_t node;
381 
382 	node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-0.2");
383 	if (node == 0) {
384 		node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-1.0");
385 		if (node == 0)
386 			return (PSCI_MISSING);
387 	}
388 
389 	if (!ofw_bus_node_status_okay(node))
390 		return (PSCI_MISSING);
391 
392 	*callfn = psci_fdt_get_callfn(node);
393 	return (0);
394 }
395 #endif
396 
397 #ifdef DEV_ACPI
398 static int
399 psci_acpi_callfn(psci_callfn_t *callfn)
400 {
401 	int flags;
402 
403 	flags = psci_acpi_bootflags();
404 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
405 		return (PSCI_MISSING);
406 
407 	*callfn = psci_acpi_get_callfn(flags);
408 	return (0);
409 }
410 #endif
411 
412 static int
413 psci_find_callfn(psci_callfn_t *callfn)
414 {
415 	int error;
416 
417 	*callfn = NULL;
418 #ifdef FDT
419 	if (USE_FDT) {
420 		error = psci_fdt_callfn(callfn);
421 		if (error != 0)
422 			return (error);
423 	}
424 #endif
425 #ifdef DEV_ACPI
426 	if (*callfn == NULL && USE_ACPI) {
427 		error = psci_acpi_callfn(callfn);
428 		if (error != 0)
429 			return (error);
430 	}
431 #endif
432 
433 	if (*callfn == NULL)
434 		return (PSCI_MISSING);
435 
436 	return (PSCI_RETVAL_SUCCESS);
437 }
438 
439 int32_t
440 psci_features(uint32_t psci_func_id)
441 {
442 
443 	if (psci_softc == NULL)
444 		return (PSCI_RETVAL_NOT_SUPPORTED);
445 
446 	/* The feature flags were added to PSCI 1.0 */
447 	if (PSCI_VER_MAJOR(psci_softc->psci_version) < 1)
448 		return (PSCI_RETVAL_NOT_SUPPORTED);
449 
450 	return (psci_call(PSCI_FNID_FEATURES, psci_func_id, 0, 0));
451 }
452 
453 int
454 psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id)
455 {
456 	uint32_t fnid;
457 
458 	fnid = PSCI_FNID_CPU_ON;
459 	if (psci_softc != NULL)
460 		fnid = psci_softc->psci_fnids[PSCI_FN_CPU_ON];
461 
462 	/* PSCI v0.1 and v0.2 both support cpu_on. */
463 	return (psci_call(fnid, cpu, entry, context_id));
464 }
465 
466 static void
467 psci_shutdown(void *xsc, int howto)
468 {
469 	uint32_t fn = 0;
470 
471 	if (psci_softc == NULL)
472 		return;
473 
474 	/* PSCI system_off and system_reset werent't supported in v0.1. */
475 	if ((howto & RB_POWEROFF) != 0)
476 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF];
477 	else if ((howto & RB_HALT) == 0)
478 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET];
479 
480 	if (fn)
481 		psci_call(fn, 0, 0, 0);
482 
483 	/* System reset and off do not return. */
484 }
485 
486 void
487 psci_reset(void)
488 {
489 
490 	psci_shutdown(NULL, 0);
491 }
492 
493 #ifdef FDT
494 /* Only support PSCI 0.1 on FDT */
495 static int
496 psci_v0_1_init(device_t dev, int default_version __unused)
497 {
498 	struct psci_softc *sc = device_get_softc(dev);
499 	int psci_fn;
500 	uint32_t psci_fnid;
501 	phandle_t node;
502 	int len;
503 
504 	/* Zero out the function ID table - Is this needed ? */
505 	for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION;
506 	    psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++)
507 		sc->psci_fnids[psci_fn] = 0;
508 
509 	/* PSCI v0.1 doesn't specify function IDs. Get them from DT */
510 	node = ofw_bus_get_node(dev);
511 
512 	if ((len = OF_getproplen(node, "cpu_suspend")) > 0) {
513 		OF_getencprop(node, "cpu_suspend", &psci_fnid, len);
514 		sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid;
515 	}
516 
517 	if ((len = OF_getproplen(node, "cpu_on")) > 0) {
518 		OF_getencprop(node, "cpu_on", &psci_fnid, len);
519 		sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid;
520 	}
521 
522 	if ((len = OF_getproplen(node, "cpu_off")) > 0) {
523 		OF_getencprop(node, "cpu_off", &psci_fnid, len);
524 		sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid;
525 	}
526 
527 	if ((len = OF_getproplen(node, "migrate")) > 0) {
528 		OF_getencprop(node, "migrate", &psci_fnid, len);
529 		sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid;
530 	}
531 
532 	sc->psci_version = (0 << 16) | 1;
533 	if (bootverbose)
534 		device_printf(dev, "PSCI version 0.1 available\n");
535 
536 	return(0);
537 }
538 #endif
539 
540 static int
541 psci_v0_2_init(device_t dev, int default_version)
542 {
543 	struct psci_softc *sc = device_get_softc(dev);
544 	int version;
545 
546 	/* PSCI v0.2 specifies explicit function IDs. */
547 	sc->psci_fnids[PSCI_FN_VERSION]		    = PSCI_FNID_VERSION;
548 	sc->psci_fnids[PSCI_FN_CPU_SUSPEND]	    = PSCI_FNID_CPU_SUSPEND;
549 	sc->psci_fnids[PSCI_FN_CPU_OFF]		    = PSCI_FNID_CPU_OFF;
550 	sc->psci_fnids[PSCI_FN_CPU_ON]		    = PSCI_FNID_CPU_ON;
551 	sc->psci_fnids[PSCI_FN_AFFINITY_INFO]	    = PSCI_FNID_AFFINITY_INFO;
552 	sc->psci_fnids[PSCI_FN_MIGRATE]		    = PSCI_FNID_MIGRATE;
553 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE]   = PSCI_FNID_MIGRATE_INFO_TYPE;
554 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU;
555 	sc->psci_fnids[PSCI_FN_SYSTEM_OFF]	    = PSCI_FNID_SYSTEM_OFF;
556 	sc->psci_fnids[PSCI_FN_SYSTEM_RESET]	    = PSCI_FNID_SYSTEM_RESET;
557 
558 	version = _psci_get_version(sc);
559 
560 	/*
561 	 * U-Boot PSCI implementation doesn't have psci_get_version()
562 	 * method implemented for many boards. In this case, use the version
563 	 * readed from FDT as fallback. No fallback method for ACPI.
564 	 */
565 	if (version == PSCI_RETVAL_NOT_SUPPORTED) {
566 		if (default_version == PSCI_RETVAL_NOT_SUPPORTED)
567 			return (1);
568 
569 		version = default_version;
570 		printf("PSCI get_version() function is not implemented, "
571 		    " assuming v%d.%d\n", PSCI_VER_MAJOR(version),
572 		    PSCI_VER_MINOR(version));
573 	}
574 
575 	sc->psci_version = version;
576 	if ((PSCI_VER_MAJOR(version) == 0 && PSCI_VER_MINOR(version) == 2) ||
577 	    PSCI_VER_MAJOR(version) == 1) {
578 		if (bootverbose)
579 			device_printf(dev, "PSCI version 0.2 compatible\n");
580 
581 		/*
582 		 * We only register this for v0.2 since v0.1 doesn't support
583 		 * system_reset.
584 		 */
585 		EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc,
586 		    SHUTDOWN_PRI_LAST);
587 
588 		return (0);
589 	}
590 
591 	device_printf(dev, "PSCI version number mismatched with DT\n");
592 	return (1);
593 }
594