xref: /freebsd/sys/dev/psci/psci.c (revision b85b9c88eb02298ea7fa3885619f54ac0e930ba4)
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 __FBSDID("$FreeBSD$");
45 
46 #include "opt_acpi.h"
47 #include "opt_platform.h"
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/bus.h>
52 #include <sys/eventhandler.h>
53 #include <sys/kernel.h>
54 #include <sys/module.h>
55 #include <sys/reboot.h>
56 
57 #include <machine/bus.h>
58 #include <machine/machdep.h>
59 
60 #ifdef DEV_ACPI
61 #include <contrib/dev/acpica/include/acpi.h>
62 #include <dev/acpica/acpivar.h>
63 #endif
64 
65 #ifdef FDT
66 #include <dev/fdt/fdt_common.h>
67 #include <dev/ofw/openfirm.h>
68 #include <dev/ofw/ofw_bus.h>
69 #include <dev/ofw/ofw_bus_subr.h>
70 #endif
71 
72 #include <dev/psci/psci.h>
73 
74 struct psci_softc {
75 	device_t        dev;
76 
77 	uint32_t	psci_version;
78 	uint32_t	psci_fnids[PSCI_FN_MAX];
79 };
80 
81 #ifdef FDT
82 static int psci_v0_1_init(device_t dev, int default_version);
83 #endif
84 static int psci_v0_2_init(device_t dev, int default_version);
85 
86 struct psci_softc *psci_softc = NULL;
87 bool psci_present;
88 
89 #ifdef __arm__
90 #define	USE_ACPI	0
91 #define	USE_FDT		1
92 #elif defined(__aarch64__)
93 #define	USE_ACPI	(arm64_bus_method == ARM64_BUS_ACPI)
94 #define	USE_FDT		(arm64_bus_method == ARM64_BUS_FDT)
95 #else
96 #error Unknown architecture
97 #endif
98 
99 #ifdef FDT
100 struct psci_init_def {
101 	int		default_version;
102 	psci_initfn_t	psci_init;
103 };
104 
105 static struct psci_init_def psci_v1_0_init_def = {
106 	.default_version = (1 << 16) | 0,
107 	.psci_init = psci_v0_2_init
108 };
109 
110 static struct psci_init_def psci_v0_2_init_def = {
111 	.default_version = (0 << 16) | 2,
112 	.psci_init = psci_v0_2_init
113 };
114 
115 static struct psci_init_def psci_v0_1_init_def = {
116 	.default_version = (0 << 16) | 1,
117 	.psci_init = psci_v0_1_init
118 };
119 
120 static struct ofw_compat_data compat_data[] = {
121 	{"arm,psci-1.0",        (uintptr_t)&psci_v1_0_init_def},
122 	{"arm,psci-0.2",        (uintptr_t)&psci_v0_2_init_def},
123 	{"arm,psci",            (uintptr_t)&psci_v0_1_init_def},
124 	{NULL,                  0}
125 };
126 #endif
127 
128 static int psci_attach(device_t, psci_initfn_t, int);
129 static void psci_shutdown(void *, int);
130 
131 static int psci_find_callfn(psci_callfn_t *);
132 static int psci_def_callfn(register_t, register_t, register_t, register_t,
133 	register_t, register_t, register_t, register_t,
134 	struct arm_smccc_res *res);
135 
136 psci_callfn_t psci_callfn = psci_def_callfn;
137 
138 static void
139 psci_init(void *dummy)
140 {
141 	psci_callfn_t new_callfn;
142 
143 	if (psci_find_callfn(&new_callfn) != PSCI_RETVAL_SUCCESS) {
144 		printf("No PSCI/SMCCC call function found\n");
145 		return;
146 	}
147 
148 	psci_callfn = new_callfn;
149 }
150 /* This needs to be before cpu_mp at SI_SUB_CPU, SI_ORDER_THIRD */
151 SYSINIT(psci_start, SI_SUB_CPU, SI_ORDER_FIRST, psci_init, NULL);
152 
153 static int
154 psci_def_callfn(register_t a __unused, register_t b __unused,
155     register_t c __unused, register_t d __unused,
156     register_t e __unused, register_t f __unused,
157     register_t g __unused, register_t h __unused,
158     struct arm_smccc_res *res __unused)
159 {
160 
161 	panic("No PSCI/SMCCC call function set");
162 }
163 
164 #ifdef FDT
165 static int psci_fdt_probe(device_t dev);
166 static int psci_fdt_attach(device_t dev);
167 
168 static device_method_t psci_fdt_methods[] = {
169 	DEVMETHOD(device_probe,     psci_fdt_probe),
170 	DEVMETHOD(device_attach,    psci_fdt_attach),
171 
172 	DEVMETHOD_END
173 };
174 
175 static driver_t psci_fdt_driver = {
176 	"psci",
177 	psci_fdt_methods,
178 	sizeof(struct psci_softc),
179 };
180 
181 static devclass_t psci_fdt_devclass;
182 
183 EARLY_DRIVER_MODULE(psci, simplebus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
184     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
185 EARLY_DRIVER_MODULE(psci, ofwbus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
186     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
187 
188 static psci_callfn_t
189 psci_fdt_get_callfn(phandle_t node)
190 {
191 	char method[16];
192 
193 	if ((OF_getprop(node, "method", method, sizeof(method))) > 0) {
194 		if (strcmp(method, "hvc") == 0)
195 			return (arm_smccc_hvc);
196 		else if (strcmp(method, "smc") == 0)
197 			return (arm_smccc_smc);
198 		else
199 			printf("psci: PSCI conduit \"%s\" invalid\n", method);
200 	} else
201 		printf("psci: PSCI conduit not supplied in the device tree\n");
202 
203 	return (NULL);
204 }
205 
206 static int
207 psci_fdt_probe(device_t dev)
208 {
209 	const struct ofw_compat_data *ocd;
210 
211 	if (!ofw_bus_status_okay(dev))
212 		return (ENXIO);
213 
214 	ocd = ofw_bus_search_compatible(dev, compat_data);
215 	if (ocd->ocd_str == NULL)
216 		return (ENXIO);
217 
218 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
219 
220 	return (BUS_PROBE_SPECIFIC);
221 }
222 
223 static int
224 psci_fdt_attach(device_t dev)
225 {
226 	const struct ofw_compat_data *ocd;
227 	struct psci_init_def *psci_init_def;
228 
229 	ocd = ofw_bus_search_compatible(dev, compat_data);
230 	psci_init_def = (struct psci_init_def *)ocd->ocd_data;
231 
232 	return (psci_attach(dev, psci_init_def->psci_init,
233 	    psci_init_def->default_version));
234 }
235 #endif
236 
237 #ifdef DEV_ACPI
238 static void psci_acpi_identify(driver_t *, device_t);
239 static int psci_acpi_probe(device_t);
240 static int psci_acpi_attach(device_t);
241 
242 static device_method_t psci_acpi_methods[] = {
243 	/* Device interface */
244 	DEVMETHOD(device_identify,	psci_acpi_identify),
245 	DEVMETHOD(device_probe,		psci_acpi_probe),
246 	DEVMETHOD(device_attach,	psci_acpi_attach),
247 
248 	DEVMETHOD_END
249 };
250 
251 static driver_t psci_acpi_driver = {
252 	"psci",
253 	psci_acpi_methods,
254 	sizeof(struct psci_softc),
255 };
256 
257 static devclass_t psci_acpi_devclass;
258 
259 EARLY_DRIVER_MODULE(psci, acpi, psci_acpi_driver, psci_acpi_devclass, 0, 0,
260     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
261 
262 static int
263 psci_acpi_bootflags(void)
264 {
265 	ACPI_TABLE_FADT *fadt;
266 	vm_paddr_t physaddr;
267 	int flags;
268 
269 	physaddr = acpi_find_table(ACPI_SIG_FADT);
270 	if (physaddr == 0)
271 		return (0);
272 
273 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
274 	if (fadt == NULL) {
275 		printf("psci: Unable to map the FADT\n");
276 		return (0);
277 	}
278 
279 	flags = fadt->ArmBootFlags;
280 
281 	acpi_unmap_table(fadt);
282 	return (flags);
283 }
284 
285 static psci_callfn_t
286 psci_acpi_get_callfn(int flags)
287 {
288 
289 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
290 		if ((flags & ACPI_FADT_PSCI_USE_HVC) != 0)
291 			return (arm_smccc_hvc);
292 		else
293 			return (arm_smccc_smc);
294 	} else {
295 		printf("psci: PSCI conduit not supplied in the device tree\n");
296 	}
297 
298 	return (NULL);
299 }
300 
301 static void
302 psci_acpi_identify(driver_t *driver, device_t parent)
303 {
304 	device_t dev;
305 	int flags;
306 
307 	flags = psci_acpi_bootflags();
308 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
309 		dev = BUS_ADD_CHILD(parent,
310 		    BUS_PASS_CPU + BUS_PASS_ORDER_FIRST, "psci", -1);
311 
312 		if (dev != NULL)
313 			acpi_set_private(dev, (void *)(uintptr_t)flags);
314 	}
315 }
316 
317 static int
318 psci_acpi_probe(device_t dev)
319 {
320 	uintptr_t flags;
321 
322 	flags = (uintptr_t)acpi_get_private(dev);
323 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
324 		return (ENXIO);
325 
326 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
327 	return (BUS_PROBE_SPECIFIC);
328 }
329 
330 static int
331 psci_acpi_attach(device_t dev)
332 {
333 
334 	return (psci_attach(dev, psci_v0_2_init, PSCI_RETVAL_NOT_SUPPORTED));
335 }
336 #endif
337 
338 static int
339 psci_attach(device_t dev, psci_initfn_t psci_init, int default_version)
340 {
341 	struct psci_softc *sc = device_get_softc(dev);
342 
343 	if (psci_softc != NULL)
344 		return (ENXIO);
345 
346 	KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL"));
347 	if (psci_init(dev, default_version))
348 		return (ENXIO);
349 
350 	psci_softc = sc;
351 	psci_present = true;
352 
353 	return (0);
354 }
355 
356 static int
357 _psci_get_version(struct psci_softc *sc)
358 {
359 	uint32_t fnid;
360 
361 	/* PSCI version wasn't supported in v0.1. */
362 	fnid = sc->psci_fnids[PSCI_FN_VERSION];
363 	if (fnid)
364 		return (psci_call(fnid, 0, 0, 0));
365 
366 	return (PSCI_RETVAL_NOT_SUPPORTED);
367 }
368 
369 int
370 psci_get_version(void)
371 {
372 
373 	if (psci_softc == NULL)
374 		return (PSCI_RETVAL_NOT_SUPPORTED);
375 	return (_psci_get_version(psci_softc));
376 }
377 
378 #ifdef FDT
379 static int
380 psci_fdt_callfn(psci_callfn_t *callfn)
381 {
382 	phandle_t node;
383 
384 	node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-0.2");
385 	if (node == 0) {
386 		node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-1.0");
387 		if (node == 0)
388 			return (PSCI_MISSING);
389 	}
390 
391 	*callfn = psci_fdt_get_callfn(node);
392 	return (0);
393 }
394 #endif
395 
396 #ifdef DEV_ACPI
397 static int
398 psci_acpi_callfn(psci_callfn_t *callfn)
399 {
400 	int flags;
401 
402 	flags = psci_acpi_bootflags();
403 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
404 		return (PSCI_MISSING);
405 
406 	*callfn = psci_acpi_get_callfn(flags);
407 	return (0);
408 }
409 #endif
410 
411 static int
412 psci_find_callfn(psci_callfn_t *callfn)
413 {
414 	int error;
415 
416 	*callfn = NULL;
417 #ifdef FDT
418 	if (USE_FDT) {
419 		error = psci_fdt_callfn(callfn);
420 		if (error != 0)
421 			return (error);
422 	}
423 #endif
424 #ifdef DEV_ACPI
425 	if (*callfn == NULL && USE_ACPI) {
426 		error = psci_acpi_callfn(callfn);
427 		if (error != 0)
428 			return (error);
429 	}
430 #endif
431 
432 	if (*callfn == NULL)
433 		return (PSCI_MISSING);
434 
435 	return (PSCI_RETVAL_SUCCESS);
436 }
437 
438 int32_t
439 psci_features(uint32_t psci_func_id)
440 {
441 
442 	if (psci_softc == NULL)
443 		return (PSCI_RETVAL_NOT_SUPPORTED);
444 
445 	/* The feature flags were added to PSCI 1.0 */
446 	if (PSCI_VER_MAJOR(psci_softc->psci_version) < 1)
447 		return (PSCI_RETVAL_NOT_SUPPORTED);
448 
449 	return (psci_call(PSCI_FNID_FEATURES, psci_func_id, 0, 0));
450 }
451 
452 int
453 psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id)
454 {
455 	uint32_t fnid;
456 
457 	fnid = PSCI_FNID_CPU_ON;
458 	if (psci_softc != NULL)
459 		fnid = psci_softc->psci_fnids[PSCI_FN_CPU_ON];
460 
461 	/* PSCI v0.1 and v0.2 both support cpu_on. */
462 	return (psci_call(fnid, cpu, entry, context_id));
463 }
464 
465 static void
466 psci_shutdown(void *xsc, int howto)
467 {
468 	uint32_t fn = 0;
469 
470 	if (psci_softc == NULL)
471 		return;
472 
473 	/* PSCI system_off and system_reset werent't supported in v0.1. */
474 	if ((howto & RB_POWEROFF) != 0)
475 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF];
476 	else if ((howto & RB_HALT) == 0)
477 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET];
478 
479 	if (fn)
480 		psci_call(fn, 0, 0, 0);
481 
482 	/* System reset and off do not return. */
483 }
484 
485 void
486 psci_reset(void)
487 {
488 
489 	psci_shutdown(NULL, 0);
490 }
491 
492 #ifdef FDT
493 /* Only support PSCI 0.1 on FDT */
494 static int
495 psci_v0_1_init(device_t dev, int default_version __unused)
496 {
497 	struct psci_softc *sc = device_get_softc(dev);
498 	int psci_fn;
499 	uint32_t psci_fnid;
500 	phandle_t node;
501 	int len;
502 
503 	/* Zero out the function ID table - Is this needed ? */
504 	for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION;
505 	    psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++)
506 		sc->psci_fnids[psci_fn] = 0;
507 
508 	/* PSCI v0.1 doesn't specify function IDs. Get them from DT */
509 	node = ofw_bus_get_node(dev);
510 
511 	if ((len = OF_getproplen(node, "cpu_suspend")) > 0) {
512 		OF_getencprop(node, "cpu_suspend", &psci_fnid, len);
513 		sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid;
514 	}
515 
516 	if ((len = OF_getproplen(node, "cpu_on")) > 0) {
517 		OF_getencprop(node, "cpu_on", &psci_fnid, len);
518 		sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid;
519 	}
520 
521 	if ((len = OF_getproplen(node, "cpu_off")) > 0) {
522 		OF_getencprop(node, "cpu_off", &psci_fnid, len);
523 		sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid;
524 	}
525 
526 	if ((len = OF_getproplen(node, "migrate")) > 0) {
527 		OF_getencprop(node, "migrate", &psci_fnid, len);
528 		sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid;
529 	}
530 
531 	sc->psci_version = (0 << 16) | 1;
532 	if (bootverbose)
533 		device_printf(dev, "PSCI version 0.1 available\n");
534 
535 	return(0);
536 }
537 #endif
538 
539 static int
540 psci_v0_2_init(device_t dev, int default_version)
541 {
542 	struct psci_softc *sc = device_get_softc(dev);
543 	int version;
544 
545 	/* PSCI v0.2 specifies explicit function IDs. */
546 	sc->psci_fnids[PSCI_FN_VERSION]		    = PSCI_FNID_VERSION;
547 	sc->psci_fnids[PSCI_FN_CPU_SUSPEND]	    = PSCI_FNID_CPU_SUSPEND;
548 	sc->psci_fnids[PSCI_FN_CPU_OFF]		    = PSCI_FNID_CPU_OFF;
549 	sc->psci_fnids[PSCI_FN_CPU_ON]		    = PSCI_FNID_CPU_ON;
550 	sc->psci_fnids[PSCI_FN_AFFINITY_INFO]	    = PSCI_FNID_AFFINITY_INFO;
551 	sc->psci_fnids[PSCI_FN_MIGRATE]		    = PSCI_FNID_MIGRATE;
552 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE]   = PSCI_FNID_MIGRATE_INFO_TYPE;
553 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU;
554 	sc->psci_fnids[PSCI_FN_SYSTEM_OFF]	    = PSCI_FNID_SYSTEM_OFF;
555 	sc->psci_fnids[PSCI_FN_SYSTEM_RESET]	    = PSCI_FNID_SYSTEM_RESET;
556 
557 	version = _psci_get_version(sc);
558 
559 	/*
560 	 * U-Boot PSCI implementation doesn't have psci_get_version()
561 	 * method implemented for many boards. In this case, use the version
562 	 * readed from FDT as fallback. No fallback method for ACPI.
563 	 */
564 	if (version == PSCI_RETVAL_NOT_SUPPORTED) {
565 		if (default_version == PSCI_RETVAL_NOT_SUPPORTED)
566 			return (1);
567 
568 		version = default_version;
569 		printf("PSCI get_version() function is not implemented, "
570 		    " assuming v%d.%d\n", PSCI_VER_MAJOR(version),
571 		    PSCI_VER_MINOR(version));
572 	}
573 
574 	sc->psci_version = version;
575 	if ((PSCI_VER_MAJOR(version) == 0 && PSCI_VER_MINOR(version) == 2) ||
576 	    PSCI_VER_MAJOR(version) == 1) {
577 		if (bootverbose)
578 			device_printf(dev, "PSCI version 0.2 compatible\n");
579 
580 		/*
581 		 * We only register this for v0.2 since v0.1 doesn't support
582 		 * system_reset.
583 		 */
584 		EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc,
585 		    SHUTDOWN_PRI_LAST);
586 
587 		return (0);
588 	}
589 
590 	device_printf(dev, "PSCI version number mismatched with DT\n");
591 	return (1);
592 }
593