xref: /freebsd/sys/dev/psci/psci.c (revision d8a0fe102c0cfdfcd5b818f850eff09d8536c9bc)
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 	psci_callfn_t	psci_call;
78 	uint32_t	psci_fnids[PSCI_FN_MAX];
79 };
80 
81 #ifdef FDT
82 static int psci_v0_1_init(device_t dev);
83 #endif
84 static int psci_v0_2_init(device_t dev);
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 static struct ofw_compat_data compat_data[] = {
100 	{"arm,psci-1.0",        (uintptr_t)psci_v0_2_init},
101 	{"arm,psci-0.2",        (uintptr_t)psci_v0_2_init},
102 	{"arm,psci",            (uintptr_t)psci_v0_1_init},
103 	{NULL,                  0}
104 };
105 #endif
106 
107 static int psci_attach(device_t, psci_initfn_t);
108 static void psci_shutdown(void *, int);
109 
110 #ifdef FDT
111 static int psci_fdt_probe(device_t dev);
112 static int psci_fdt_attach(device_t dev);
113 
114 static device_method_t psci_fdt_methods[] = {
115 	DEVMETHOD(device_probe,     psci_fdt_probe),
116 	DEVMETHOD(device_attach,    psci_fdt_attach),
117 
118 	DEVMETHOD_END
119 };
120 
121 static driver_t psci_fdt_driver = {
122 	"psci",
123 	psci_fdt_methods,
124 	sizeof(struct psci_softc),
125 };
126 
127 static devclass_t psci_fdt_devclass;
128 
129 EARLY_DRIVER_MODULE(psci, simplebus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
130     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
131 EARLY_DRIVER_MODULE(psci, ofwbus, psci_fdt_driver, psci_fdt_devclass, 0, 0,
132     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
133 
134 static psci_callfn_t
135 psci_fdt_get_callfn(phandle_t node)
136 {
137 	char method[16];
138 
139 	if ((OF_getprop(node, "method", method, sizeof(method))) > 0) {
140 		if (strcmp(method, "hvc") == 0)
141 			return (psci_hvc_despatch);
142 		else if (strcmp(method, "smc") == 0)
143 			return (psci_smc_despatch);
144 		else
145 			printf("psci: PSCI conduit \"%s\" invalid\n", method);
146 	} else
147 		printf("psci: PSCI conduit not supplied in the device tree\n");
148 
149 	return (NULL);
150 }
151 
152 static int
153 psci_fdt_probe(device_t dev)
154 {
155 	const struct ofw_compat_data *ocd;
156 
157 	if (!ofw_bus_status_okay(dev))
158 		return (ENXIO);
159 
160 	ocd = ofw_bus_search_compatible(dev, compat_data);
161 	if (ocd->ocd_str == NULL)
162 		return (ENXIO);
163 
164 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
165 
166 	return (BUS_PROBE_SPECIFIC);
167 }
168 
169 static int
170 psci_fdt_attach(device_t dev)
171 {
172 	struct psci_softc *sc = device_get_softc(dev);
173 	const struct ofw_compat_data *ocd;
174 	psci_initfn_t psci_init;
175 	phandle_t node;
176 
177 	ocd = ofw_bus_search_compatible(dev, compat_data);
178 	psci_init = (psci_initfn_t)ocd->ocd_data;
179 
180 	node = ofw_bus_get_node(dev);
181 	sc->psci_call = psci_fdt_get_callfn(node);
182 
183 	return (psci_attach(dev, psci_init));
184 }
185 #endif
186 
187 #ifdef DEV_ACPI
188 static void psci_acpi_identify(driver_t *, device_t);
189 static int psci_acpi_probe(device_t);
190 static int psci_acpi_attach(device_t);
191 
192 static device_method_t psci_acpi_methods[] = {
193 	/* Device interface */
194 	DEVMETHOD(device_identify,	psci_acpi_identify),
195 	DEVMETHOD(device_probe,		psci_acpi_probe),
196 	DEVMETHOD(device_attach,	psci_acpi_attach),
197 
198 	DEVMETHOD_END
199 };
200 
201 static driver_t psci_acpi_driver = {
202 	"psci",
203 	psci_acpi_methods,
204 	sizeof(struct psci_softc),
205 };
206 
207 static devclass_t psci_acpi_devclass;
208 
209 EARLY_DRIVER_MODULE(psci, acpi, psci_acpi_driver, psci_acpi_devclass, 0, 0,
210     BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);
211 
212 static int
213 psci_acpi_bootflags(void)
214 {
215 	ACPI_TABLE_FADT *fadt;
216 	vm_paddr_t physaddr;
217 	int flags;
218 
219 	physaddr = acpi_find_table(ACPI_SIG_FADT);
220 	if (physaddr == 0)
221 		return (0);
222 
223 	fadt = acpi_map_table(physaddr, ACPI_SIG_FADT);
224 	if (fadt == NULL) {
225 		printf("psci: Unable to map the FADT\n");
226 		return (0);
227 	}
228 
229 	flags = fadt->ArmBootFlags;
230 
231 	acpi_unmap_table(fadt);
232 	return (flags);
233 }
234 
235 static psci_callfn_t
236 psci_acpi_get_callfn(int flags)
237 {
238 
239 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
240 		if ((flags & ACPI_FADT_PSCI_USE_HVC) != 0)
241 			return (psci_hvc_despatch);
242 		else
243 			return (psci_smc_despatch);
244 	} else {
245 		printf("psci: PSCI conduit not supplied in the device tree\n");
246 	}
247 
248 	return (NULL);
249 }
250 
251 static void
252 psci_acpi_identify(driver_t *driver, device_t parent)
253 {
254 	device_t dev;
255 	int flags;
256 
257 	flags = psci_acpi_bootflags();
258 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) != 0) {
259 		dev = BUS_ADD_CHILD(parent,
260 		    BUS_PASS_CPU + BUS_PASS_ORDER_FIRST, "psci", -1);
261 
262 		if (dev != NULL)
263 			acpi_set_private(dev, (void *)(uintptr_t)flags);
264 	}
265 }
266 
267 static int
268 psci_acpi_probe(device_t dev)
269 {
270 	uintptr_t flags;
271 
272 	flags = (uintptr_t)acpi_get_private(dev);
273 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
274 		return (ENXIO);
275 
276 	device_set_desc(dev, "ARM Power State Co-ordination Interface Driver");
277 	return (BUS_PROBE_SPECIFIC);
278 }
279 
280 static int
281 psci_acpi_attach(device_t dev)
282 {
283 	struct psci_softc *sc = device_get_softc(dev);
284 	uintptr_t flags;
285 
286 	flags = (uintptr_t)acpi_get_private(dev);
287 	if ((flags & ACPI_FADT_PSCI_USE_HVC) != 0)
288 		sc->psci_call = psci_hvc_despatch;
289 	else
290 		sc->psci_call = psci_smc_despatch;
291 
292 	return (psci_attach(dev, psci_v0_2_init));
293 }
294 #endif
295 
296 static int
297 psci_attach(device_t dev, psci_initfn_t psci_init)
298 {
299 	struct psci_softc *sc = device_get_softc(dev);
300 
301 	if (psci_softc != NULL)
302 		return (ENXIO);
303 
304 	if (sc->psci_call == NULL)
305 		return (ENXIO);
306 
307 	KASSERT(psci_init != NULL, ("PSCI init function cannot be NULL"));
308 	if (psci_init(dev))
309 		return (ENXIO);
310 
311 	psci_softc = sc;
312 
313 	return (0);
314 }
315 
316 static int
317 psci_get_version(struct psci_softc *sc)
318 {
319 	uint32_t fnid;
320 
321 	/* PSCI version wasn't supported in v0.1. */
322 	fnid = sc->psci_fnids[PSCI_FN_VERSION];
323 	if (fnid)
324 		return (sc->psci_call(fnid, 0, 0, 0));
325 
326 	return (PSCI_RETVAL_NOT_SUPPORTED);
327 }
328 
329 #ifdef FDT
330 static int
331 psci_fdt_callfn(psci_callfn_t *callfn)
332 {
333 	phandle_t node;
334 
335 	node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-0.2");
336 	if (node == 0) {
337 		node = ofw_bus_find_compatible(OF_peer(0), "arm,psci-1.0");
338 		if (node == 0)
339 			return (PSCI_MISSING);
340 	}
341 
342 	*callfn = psci_fdt_get_callfn(node);
343 	return (0);
344 }
345 #endif
346 
347 #ifdef DEV_ACPI
348 static int
349 psci_acpi_callfn(psci_callfn_t *callfn)
350 {
351 	int flags;
352 
353 	flags = psci_acpi_bootflags();
354 	if ((flags & ACPI_FADT_PSCI_COMPLIANT) == 0)
355 		return (PSCI_MISSING);
356 
357 	*callfn = psci_acpi_get_callfn(flags);
358 	return (0);
359 }
360 #endif
361 
362 int
363 psci_cpu_on(unsigned long cpu, unsigned long entry, unsigned long context_id)
364 {
365 	psci_callfn_t callfn;
366 	uint32_t fnid;
367 	int error;
368 
369 	if (psci_softc == NULL) {
370 		fnid = PSCI_FNID_CPU_ON;
371 		callfn = NULL;
372 #ifdef FDT
373 		if (USE_FDT) {
374 			error = psci_fdt_callfn(&callfn);
375 			if (error != 0)
376 				return (error);
377 		}
378 #endif
379 #ifdef DEV_ACPI
380 		if (callfn == NULL && USE_ACPI) {
381 			error = psci_acpi_callfn(&callfn);
382 			if (error != 0)
383 				return (error);
384 		}
385 #endif
386 
387 		if (callfn == NULL)
388 			return (PSCI_MISSING);
389 	} else {
390 		callfn = psci_softc->psci_call;
391 		fnid = psci_softc->psci_fnids[PSCI_FN_CPU_ON];
392 	}
393 
394 	/* PSCI v0.1 and v0.2 both support cpu_on. */
395 	return (callfn(fnid, cpu, entry, context_id));
396 }
397 
398 static void
399 psci_shutdown(void *xsc, int howto)
400 {
401 	uint32_t fn = 0;
402 
403 	if (psci_softc == NULL)
404 		return;
405 
406 	/* PSCI system_off and system_reset werent't supported in v0.1. */
407 	if ((howto & RB_POWEROFF) != 0)
408 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_OFF];
409 	else if ((howto & RB_HALT) == 0)
410 		fn = psci_softc->psci_fnids[PSCI_FN_SYSTEM_RESET];
411 
412 	if (fn)
413 		psci_softc->psci_call(fn, 0, 0, 0);
414 
415 	/* System reset and off do not return. */
416 }
417 
418 void
419 psci_reset(void)
420 {
421 
422 	psci_shutdown(NULL, 0);
423 }
424 
425 #ifdef FDT
426 /* Only support PSCI 0.1 on FDT */
427 static int
428 psci_v0_1_init(device_t dev)
429 {
430 	struct psci_softc *sc = device_get_softc(dev);
431 	int psci_fn;
432 	uint32_t psci_fnid;
433 	phandle_t node;
434 	int len;
435 
436 
437 	/* Zero out the function ID table - Is this needed ? */
438 	for (psci_fn = PSCI_FN_VERSION, psci_fnid = PSCI_FNID_VERSION;
439 	    psci_fn < PSCI_FN_MAX; psci_fn++, psci_fnid++)
440 		sc->psci_fnids[psci_fn] = 0;
441 
442 	/* PSCI v0.1 doesn't specify function IDs. Get them from DT */
443 	node = ofw_bus_get_node(dev);
444 
445 	if ((len = OF_getproplen(node, "cpu_suspend")) > 0) {
446 		OF_getencprop(node, "cpu_suspend", &psci_fnid, len);
447 		sc->psci_fnids[PSCI_FN_CPU_SUSPEND] = psci_fnid;
448 	}
449 
450 	if ((len = OF_getproplen(node, "cpu_on")) > 0) {
451 		OF_getencprop(node, "cpu_on", &psci_fnid, len);
452 		sc->psci_fnids[PSCI_FN_CPU_ON] = psci_fnid;
453 	}
454 
455 	if ((len = OF_getproplen(node, "cpu_off")) > 0) {
456 		OF_getencprop(node, "cpu_off", &psci_fnid, len);
457 		sc->psci_fnids[PSCI_FN_CPU_OFF] = psci_fnid;
458 	}
459 
460 	if ((len = OF_getproplen(node, "migrate")) > 0) {
461 		OF_getencprop(node, "migrate", &psci_fnid, len);
462 		sc->psci_fnids[PSCI_FN_MIGRATE] = psci_fnid;
463 	}
464 
465 	if (bootverbose)
466 		device_printf(dev, "PSCI version 0.1 available\n");
467 
468 	return(0);
469 }
470 #endif
471 
472 static int
473 psci_v0_2_init(device_t dev)
474 {
475 	struct psci_softc *sc = device_get_softc(dev);
476 	int version;
477 
478 	/* PSCI v0.2 specifies explicit function IDs. */
479 	sc->psci_fnids[PSCI_FN_VERSION]		    = PSCI_FNID_VERSION;
480 	sc->psci_fnids[PSCI_FN_CPU_SUSPEND]	    = PSCI_FNID_CPU_SUSPEND;
481 	sc->psci_fnids[PSCI_FN_CPU_OFF]		    = PSCI_FNID_CPU_OFF;
482 	sc->psci_fnids[PSCI_FN_CPU_ON]		    = PSCI_FNID_CPU_ON;
483 	sc->psci_fnids[PSCI_FN_AFFINITY_INFO]	    = PSCI_FNID_AFFINITY_INFO;
484 	sc->psci_fnids[PSCI_FN_MIGRATE]		    = PSCI_FNID_MIGRATE;
485 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_TYPE]   = PSCI_FNID_MIGRATE_INFO_TYPE;
486 	sc->psci_fnids[PSCI_FN_MIGRATE_INFO_UP_CPU] = PSCI_FNID_MIGRATE_INFO_UP_CPU;
487 	sc->psci_fnids[PSCI_FN_SYSTEM_OFF]	    = PSCI_FNID_SYSTEM_OFF;
488 	sc->psci_fnids[PSCI_FN_SYSTEM_RESET]	    = PSCI_FNID_SYSTEM_RESET;
489 
490 	version = psci_get_version(sc);
491 
492 	if (version == PSCI_RETVAL_NOT_SUPPORTED)
493 		return (1);
494 
495 	if ((PSCI_VER_MAJOR(version) == 0 && PSCI_VER_MINOR(version) == 2) ||
496 	    PSCI_VER_MAJOR(version) == 1) {
497 		if (bootverbose)
498 			device_printf(dev, "PSCI version 0.2 compatible\n");
499 
500 		/*
501 		 * We only register this for v0.2 since v0.1 doesn't support
502 		 * system_reset.
503 		 */
504 		EVENTHANDLER_REGISTER(shutdown_final, psci_shutdown, sc,
505 		    SHUTDOWN_PRI_LAST);
506 
507 		return (0);
508 	}
509 
510 	device_printf(dev, "PSCI version number mismatched with DT\n");
511 	return (1);
512 }
513