xref: /freebsd/sys/dev/psci/psci.c (revision b9f654b163bce26de79705e77b872427c9f2afa1)
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 
88 #ifdef __arm__
89 #define	USE_ACPI	0
90 #define	USE_FDT		1
91 #elif defined(__aarch64__)
92 #define	USE_ACPI	(arm64_bus_method == ARM64_BUS_ACPI)
93 #define	USE_FDT		(arm64_bus_method == ARM64_BUS_FDT)
94 #else
95 #error Unknown architecture
96 #endif
97 
98 #ifdef FDT
99 struct psci_init_def {
100 	int		default_version;
101 	psci_initfn_t	psci_init;
102 };
103 
104 static struct psci_init_def psci_v1_0_init_def = {
105 	.default_version = (1 << 16) | 0,
106 	.psci_init = psci_v0_2_init
107 };
108 
109 static struct psci_init_def psci_v0_2_init_def = {
110 	.default_version = (0 << 16) | 2,
111 	.psci_init = psci_v0_2_init
112 };
113 
114 static struct psci_init_def psci_v0_1_init_def = {
115 	.default_version = (0 << 16) | 1,
116 	.psci_init = psci_v0_1_init
117 };
118 
119 static struct ofw_compat_data compat_data[] = {
120 	{"arm,psci-1.0",        (uintptr_t)&psci_v1_0_init_def},
121 	{"arm,psci-0.2",        (uintptr_t)&psci_v0_2_init_def},
122 	{"arm,psci",            (uintptr_t)&psci_v0_1_init_def},
123 	{NULL,                  0}
124 };
125 #endif
126 
127 static int psci_attach(device_t, psci_initfn_t, int);
128 static void psci_shutdown(void *, int);
129 
130 static int psci_find_callfn(psci_callfn_t *);
131 static int psci_def_callfn(register_t, register_t, register_t, register_t);
132 
133 psci_callfn_t psci_callfn = psci_def_callfn;
134 
135 static void
136 psci_init(void *dummy)
137 {
138 	psci_callfn_t new_callfn;
139 
140 	if (psci_find_callfn(&new_callfn) != PSCI_RETVAL_SUCCESS) {
141 		printf("No PSCI/SMCCC call function found\n");
142 		return;
143 	}
144 
145 	psci_callfn = new_callfn;
146 }
147 /* This needs to be before cpu_mp at SI_SUB_CPU, SI_ORDER_THIRD */
148 SYSINIT(psci_start, SI_SUB_CPU, SI_ORDER_FIRST, psci_init, NULL);
149 
150 static int
151 psci_def_callfn(register_t a __unused, register_t b __unused,
152     register_t c __unused, register_t d __unused)
153 {
154 
155 	panic("No PSCI/SMCCC call function set");
156 }
157 
158 #ifdef FDT
159 static int psci_fdt_probe(device_t dev);
160 static int psci_fdt_attach(device_t dev);
161 
162 static device_method_t psci_fdt_methods[] = {
163 	DEVMETHOD(device_probe,     psci_fdt_probe),
164 	DEVMETHOD(device_attach,    psci_fdt_attach),
165 
166 	DEVMETHOD_END
167 };
168 
169 static driver_t psci_fdt_driver = {
170 	"psci",
171 	psci_fdt_methods,
172 	sizeof(struct psci_softc),
173 };
174 
175 static devclass_t psci_fdt_devclass;
176 
177 EARLY_DRIVER_MODULE(psci, simplebus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
178     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
179 EARLY_DRIVER_MODULE(psci, ofwbus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
180     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
181 
182 static psci_callfn_t
183 psci_fdt_get_callfn(phandle_t node)
184 {
185 	char method[16];
186 
187 	if ((OF_getprop(node, "method", method, sizeof(method))) > 0) {
188 		if (strcmp(method, "hvc") == 0)
189 			return (psci_hvc_despatch);
190 		else if (strcmp(method, "smc") == 0)
191 			return (psci_smc_despatch);
192 		else
193 			printf("psci: PSCI conduit \"%s\" invalid\n", method);
194 	} else
195 		printf("psci: PSCI conduit not supplied in the device tree\n");
196 
197 	return (NULL);
198 }
199 
200 static int
201 psci_fdt_probe(device_t dev)
202 {
203 	const struct ofw_compat_data *ocd;
204 
205 	if (!ofw_bus_status_okay(dev))
206 		return (ENXIO);
207 
208 	ocd = ofw_bus_search_compatible(dev, compat_data);
209 	if (ocd->ocd_str == NULL)
210 		return (ENXIO);
211 
212 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
213 
214 	return (BUS_PROBE_SPECIFIC);
215 }
216 
217 static int
218 psci_fdt_attach(device_t dev)
219 {
220 	const struct ofw_compat_data *ocd;
221 	struct psci_init_def *psci_init_def;
222 
223 	ocd = ofw_bus_search_compatible(dev, compat_data);
224 	psci_init_def = (struct psci_init_def *)ocd->ocd_data;
225 
226 	return (psci_attach(dev, psci_init_def->psci_init,
227 	    psci_init_def->default_version));
228 }
229 #endif
230 
231 #ifdef DEV_ACPI
232 static void psci_acpi_identify(driver_t *, device_t);
233 static int psci_acpi_probe(device_t);
234 static int psci_acpi_attach(device_t);
235 
236 static device_method_t psci_acpi_methods[] = {
237 	/* Device interface */
238 	DEVMETHOD(device_identify,	psci_acpi_identify),
239 	DEVMETHOD(device_probe,		psci_acpi_probe),
240 	DEVMETHOD(device_attach,	psci_acpi_attach),
241 
242 	DEVMETHOD_END
243 };
244 
245 static driver_t psci_acpi_driver = {
246 	"psci",
247 	psci_acpi_methods,
248 	sizeof(struct psci_softc),
249 };
250 
251 static devclass_t psci_acpi_devclass;
252 
253 EARLY_DRIVER_MODULE(psci, acpi, psci_acpi_driver, psci_acpi_devclass, 0, 0,
254     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
255 
256 static int
257 psci_acpi_bootflags(void)
258 {
259 	ACPI_TABLE_FADT *fadt;
260 	vm_paddr_t physaddr;
261 	int flags;
262 
263 	physaddr = acpi_find_table(ACPI_SIG_FADT);
264 	if (physaddr == 0)
265 		return (0);
266 
267 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
268 	if (fadt == NULL) {
269 		printf("psci: Unable to map the FADT\n");
270 		return (0);
271 	}
272 
273 	flags = fadt->ArmBootFlags;
274 
275 	acpi_unmap_table(fadt);
276 	return (flags);
277 }
278 
279 static psci_callfn_t
280 psci_acpi_get_callfn(int flags)
281 {
282 
283 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
284 		if ((flags & ACPI_FADT_PSCI_USE_HVC) != 0)
285 			return (psci_hvc_despatch);
286 		else
287 			return (psci_smc_despatch);
288 	} else {
289 		printf("psci: PSCI conduit not supplied in the device tree\n");
290 	}
291 
292 	return (NULL);
293 }
294 
295 static void
296 psci_acpi_identify(driver_t *driver, device_t parent)
297 {
298 	device_t dev;
299 	int flags;
300 
301 	flags = psci_acpi_bootflags();
302 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
303 		dev = BUS_ADD_CHILD(parent,
304 		    BUS_PASS_CPU + BUS_PASS_ORDER_FIRST, "psci", -1);
305 
306 		if (dev != NULL)
307 			acpi_set_private(dev, (void *)(uintptr_t)flags);
308 	}
309 }
310 
311 static int
312 psci_acpi_probe(device_t dev)
313 {
314 	uintptr_t flags;
315 
316 	flags = (uintptr_t)acpi_get_private(dev);
317 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
318 		return (ENXIO);
319 
320 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
321 	return (BUS_PROBE_SPECIFIC);
322 }
323 
324 static int
325 psci_acpi_attach(device_t dev)
326 {
327 
328 	return (psci_attach(dev, psci_v0_2_init, PSCI_RETVAL_NOT_SUPPORTED));
329 }
330 #endif
331 
332 static int
333 psci_attach(device_t dev, psci_initfn_t psci_init, int default_version)
334 {
335 	struct psci_softc *sc = device_get_softc(dev);
336 
337 	if (psci_softc != NULL)
338 		return (ENXIO);
339 
340 	KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL"));
341 	if (psci_init(dev, default_version))
342 		return (ENXIO);
343 
344 	psci_softc = sc;
345 
346 	return (0);
347 }
348 
349 static int
350 _psci_get_version(struct psci_softc *sc)
351 {
352 	uint32_t fnid;
353 
354 	/* PSCI version wasn't supported in v0.1. */
355 	fnid = sc->psci_fnids[PSCI_FN_VERSION];
356 	if (fnid)
357 		return (psci_call(fnid, 0, 0, 0));
358 
359 	return (PSCI_RETVAL_NOT_SUPPORTED);
360 }
361 
362 int
363 psci_get_version(void)
364 {
365 
366 	if (psci_softc == NULL)
367 		return (PSCI_RETVAL_NOT_SUPPORTED);
368 	return (_psci_get_version(psci_softc));
369 }
370 
371 #ifdef FDT
372 static int
373 psci_fdt_callfn(psci_callfn_t *callfn)
374 {
375 	phandle_t node;
376 
377 	node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-0.2");
378 	if (node == 0) {
379 		node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-1.0");
380 		if (node == 0)
381 			return (PSCI_MISSING);
382 	}
383 
384 	*callfn = psci_fdt_get_callfn(node);
385 	return (0);
386 }
387 #endif
388 
389 #ifdef DEV_ACPI
390 static int
391 psci_acpi_callfn(psci_callfn_t *callfn)
392 {
393 	int flags;
394 
395 	flags = psci_acpi_bootflags();
396 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
397 		return (PSCI_MISSING);
398 
399 	*callfn = psci_acpi_get_callfn(flags);
400 	return (0);
401 }
402 #endif
403 
404 static int
405 psci_find_callfn(psci_callfn_t *callfn)
406 {
407 	int error;
408 
409 	*callfn = NULL;
410 #ifdef FDT
411 	if (USE_FDT) {
412 		error = psci_fdt_callfn(callfn);
413 		if (error != 0)
414 			return (error);
415 	}
416 #endif
417 #ifdef DEV_ACPI
418 	if (*callfn == NULL && USE_ACPI) {
419 		error = psci_acpi_callfn(callfn);
420 		if (error != 0)
421 			return (error);
422 	}
423 #endif
424 
425 	if (*callfn == NULL)
426 		return (PSCI_MISSING);
427 
428 	return (PSCI_RETVAL_SUCCESS);
429 }
430 
431 int32_t
432 psci_features(uint32_t psci_func_id)
433 {
434 
435 	if (psci_softc == NULL)
436 		return (PSCI_RETVAL_NOT_SUPPORTED);
437 
438 	/* The feature flags were added to PSCI 1.0 */
439 	if (PSCI_VER_MAJOR(psci_softc->psci_version) < 1)
440 		return (PSCI_RETVAL_NOT_SUPPORTED);
441 
442 	return (psci_call(PSCI_FNID_FEATURES, psci_func_id, 0, 0));
443 }
444 
445 int
446 psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id)
447 {
448 	uint32_t fnid;
449 
450 	fnid = PSCI_FNID_CPU_ON;
451 	if (psci_softc != NULL)
452 		fnid = psci_softc->psci_fnids[PSCI_FN_CPU_ON];
453 
454 	/* PSCI v0.1 and v0.2 both support cpu_on. */
455 	return (psci_call(fnid, cpu, entry, context_id));
456 }
457 
458 static void
459 psci_shutdown(void *xsc, int howto)
460 {
461 	uint32_t fn = 0;
462 
463 	if (psci_softc == NULL)
464 		return;
465 
466 	/* PSCI system_off and system_reset werent't supported in v0.1. */
467 	if ((howto & RB_POWEROFF) != 0)
468 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF];
469 	else if ((howto & RB_HALT) == 0)
470 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET];
471 
472 	if (fn)
473 		psci_call(fn, 0, 0, 0);
474 
475 	/* System reset and off do not return. */
476 }
477 
478 void
479 psci_reset(void)
480 {
481 
482 	psci_shutdown(NULL, 0);
483 }
484 
485 #ifdef FDT
486 /* Only support PSCI 0.1 on FDT */
487 static int
488 psci_v0_1_init(device_t dev, int default_version __unused)
489 {
490 	struct psci_softc *sc = device_get_softc(dev);
491 	int psci_fn;
492 	uint32_t psci_fnid;
493 	phandle_t node;
494 	int len;
495 
496 
497 	/* Zero out the function ID table - Is this needed ? */
498 	for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION;
499 	    psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++)
500 		sc->psci_fnids[psci_fn] = 0;
501 
502 	/* PSCI v0.1 doesn't specify function IDs. Get them from DT */
503 	node = ofw_bus_get_node(dev);
504 
505 	if ((len = OF_getproplen(node, "cpu_suspend")) > 0) {
506 		OF_getencprop(node, "cpu_suspend", &psci_fnid, len);
507 		sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid;
508 	}
509 
510 	if ((len = OF_getproplen(node, "cpu_on")) > 0) {
511 		OF_getencprop(node, "cpu_on", &psci_fnid, len);
512 		sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid;
513 	}
514 
515 	if ((len = OF_getproplen(node, "cpu_off")) > 0) {
516 		OF_getencprop(node, "cpu_off", &psci_fnid, len);
517 		sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid;
518 	}
519 
520 	if ((len = OF_getproplen(node, "migrate")) > 0) {
521 		OF_getencprop(node, "migrate", &psci_fnid, len);
522 		sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid;
523 	}
524 
525 	sc->psci_version = (0 << 16) | 1;
526 	if (bootverbose)
527 		device_printf(dev, "PSCI version 0.1 available\n");
528 
529 	return(0);
530 }
531 #endif
532 
533 static int
534 psci_v0_2_init(device_t dev, int default_version)
535 {
536 	struct psci_softc *sc = device_get_softc(dev);
537 	int version;
538 
539 	/* PSCI v0.2 specifies explicit function IDs. */
540 	sc->psci_fnids[PSCI_FN_VERSION]		    = PSCI_FNID_VERSION;
541 	sc->psci_fnids[PSCI_FN_CPU_SUSPEND]	    = PSCI_FNID_CPU_SUSPEND;
542 	sc->psci_fnids[PSCI_FN_CPU_OFF]		    = PSCI_FNID_CPU_OFF;
543 	sc->psci_fnids[PSCI_FN_CPU_ON]		    = PSCI_FNID_CPU_ON;
544 	sc->psci_fnids[PSCI_FN_AFFINITY_INFO]	    = PSCI_FNID_AFFINITY_INFO;
545 	sc->psci_fnids[PSCI_FN_MIGRATE]		    = PSCI_FNID_MIGRATE;
546 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE]   = PSCI_FNID_MIGRATE_INFO_TYPE;
547 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU;
548 	sc->psci_fnids[PSCI_FN_SYSTEM_OFF]	    = PSCI_FNID_SYSTEM_OFF;
549 	sc->psci_fnids[PSCI_FN_SYSTEM_RESET]	    = PSCI_FNID_SYSTEM_RESET;
550 
551 	version = _psci_get_version(sc);
552 
553 	/*
554 	 * U-Boot PSCI implementation doesn't have psci_get_version()
555 	 * method implemented for many boards. In this case, use the version
556 	 * readed from FDT as fallback. No fallback method for ACPI.
557 	 */
558 	if (version == PSCI_RETVAL_NOT_SUPPORTED) {
559 		if (default_version == PSCI_RETVAL_NOT_SUPPORTED)
560 			return (1);
561 
562 		version = default_version;
563 		printf("PSCI get_version() function is not implemented, "
564 		    " assuming v%d.%d\n", PSCI_VER_MAJOR(version),
565 		    PSCI_VER_MINOR(version));
566 	}
567 
568 	sc->psci_version = version;
569 	if ((PSCI_VER_MAJOR(version) == 0 && PSCI_VER_MINOR(version) == 2) ||
570 	    PSCI_VER_MAJOR(version) == 1) {
571 		if (bootverbose)
572 			device_printf(dev, "PSCI version 0.2 compatible\n");
573 
574 		/*
575 		 * We only register this for v0.2 since v0.1 doesn't support
576 		 * system_reset.
577 		 */
578 		EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc,
579 		    SHUTDOWN_PRI_LAST);
580 
581 		return (0);
582 	}
583 
584 	device_printf(dev, "PSCI version number mismatched with DT\n");
585 	return (1);
586 }
587