xref: /rk3399_ARM-atf/services/std_svc/sdei/sdei_main.c (revision 091f39675a98ee9e22ed78f52e239880bedf8911)
1 /*
2  * Copyright (c) 2017-2018, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <arch_helpers.h>
8 #include <assert.h>
9 #include <bl31.h>
10 #include <bl_common.h>
11 #include <cassert.h>
12 #include <context.h>
13 #include <debug.h>
14 #include <ehf.h>
15 #include <interrupt_mgmt.h>
16 #include <platform.h>
17 #include <pubsub.h>
18 #include <runtime_svc.h>
19 #include <sdei.h>
20 #include <stddef.h>
21 #include <string.h>
22 #include <utils.h>
23 #include "sdei_private.h"
24 
25 #define MAJOR_VERSION	1ULL
26 #define MINOR_VERSION	0ULL
27 #define VENDOR_VERSION	0ULL
28 
29 #define MAKE_SDEI_VERSION(_major, _minor, _vendor) \
30 	((((_major)) << 48ULL) | (((_minor)) << 32ULL) | (_vendor))
31 
32 #define LOWEST_INTR_PRIORITY		0xff
33 
34 #define is_valid_affinity(_mpidr)	(plat_core_pos_by_mpidr(_mpidr) >= 0)
35 
36 CASSERT(PLAT_SDEI_CRITICAL_PRI < PLAT_SDEI_NORMAL_PRI,
37 		sdei_critical_must_have_higher_priority);
38 
39 static unsigned int num_dyn_priv_slots, num_dyn_shrd_slots;
40 
41 /* Initialise SDEI map entries */
42 static void init_map(sdei_ev_map_t *map)
43 {
44 	map->reg_count = 0;
45 }
46 
47 /* Convert mapping to SDEI class */
48 static sdei_class_t map_to_class(sdei_ev_map_t *map)
49 {
50 	return is_event_critical(map) ? SDEI_CRITICAL : SDEI_NORMAL;
51 }
52 
53 /* Clear SDEI event entries except state */
54 static void clear_event_entries(sdei_entry_t *se)
55 {
56 	se->ep = 0;
57 	se->arg = 0;
58 	se->affinity = 0;
59 	se->reg_flags = 0;
60 }
61 
62 /* Perform CPU-specific state initialisation */
63 static void *sdei_cpu_on_init(const void *arg)
64 {
65 	unsigned int i;
66 	sdei_ev_map_t *map;
67 	sdei_entry_t *se;
68 
69 	/* Initialize private mappings on this CPU */
70 	for_each_private_map(i, map) {
71 		se = get_event_entry(map);
72 		clear_event_entries(se);
73 		se->state = 0;
74 	}
75 
76 	SDEI_LOG("Private events initialized on %lx\n", read_mpidr_el1());
77 
78 	/* All PEs start with SDEI events masked */
79 	(void) sdei_pe_mask();
80 
81 	return NULL;
82 }
83 
84 /* Initialise an SDEI class */
85 static void sdei_class_init(sdei_class_t class)
86 {
87 	unsigned int i;
88 	bool zero_found __unused = false;
89 	int ev_num_so_far __unused;
90 	sdei_ev_map_t *map;
91 
92 	/* Sanity check and configuration of shared events */
93 	ev_num_so_far = -1;
94 	for_each_shared_map(i, map) {
95 #if ENABLE_ASSERTIONS
96 		/* Ensure mappings are sorted */
97 		assert((ev_num_so_far < 0) || (map->ev_num > ev_num_so_far));
98 
99 		ev_num_so_far = map->ev_num;
100 
101 		/* Event 0 must not be shared */
102 		assert(map->ev_num != SDEI_EVENT_0);
103 
104 		/* Check for valid event */
105 		assert(map->ev_num >= 0);
106 
107 		/* Make sure it's a shared event */
108 		assert(is_event_shared(map));
109 
110 		/* No shared mapping should have signalable property */
111 		assert(!is_event_signalable(map));
112 
113 		/* Shared mappings can't be explicit */
114 		assert(!is_map_explicit(map));
115 #endif
116 
117 		/* Skip initializing the wrong priority */
118 		if (map_to_class(map) != class)
119 			continue;
120 
121 		/* Platform events are always bound, so set the bound flag */
122 		if (is_map_dynamic(map)) {
123 			assert(map->intr == SDEI_DYN_IRQ);
124 			assert(is_event_normal(map));
125 			num_dyn_shrd_slots++;
126 		} else {
127 			/* Shared mappings must be bound to shared interrupt */
128 			assert(plat_ic_is_spi(map->intr) != 0);
129 			set_map_bound(map);
130 		}
131 
132 		init_map(map);
133 	}
134 
135 	/* Sanity check and configuration of private events for this CPU */
136 	ev_num_so_far = -1;
137 	for_each_private_map(i, map) {
138 #if ENABLE_ASSERTIONS
139 		/* Ensure mappings are sorted */
140 		assert((ev_num_so_far < 0) || (map->ev_num > ev_num_so_far));
141 
142 		ev_num_so_far = map->ev_num;
143 
144 		if (map->ev_num == SDEI_EVENT_0) {
145 			zero_found = true;
146 
147 			/* Event 0 must be a Secure SGI */
148 			assert(is_secure_sgi(map->intr));
149 
150 			/*
151 			 * Event 0 can have only have signalable flag (apart
152 			 * from being private
153 			 */
154 			assert(map->map_flags == (SDEI_MAPF_SIGNALABLE |
155 						SDEI_MAPF_PRIVATE));
156 		} else {
157 			/* No other mapping should have signalable property */
158 			assert(!is_event_signalable(map));
159 		}
160 
161 		/* Check for valid event */
162 		assert(map->ev_num >= 0);
163 
164 		/* Make sure it's a private event */
165 		assert(is_event_private(map));
166 
167 		/*
168 		 * Other than priority, explicit events can only have explicit
169 		 * and private flags set.
170 		 */
171 		if (is_map_explicit(map)) {
172 			assert((map->map_flags | SDEI_MAPF_CRITICAL) ==
173 					(SDEI_MAPF_EXPLICIT | SDEI_MAPF_PRIVATE
174 					| SDEI_MAPF_CRITICAL));
175 		}
176 #endif
177 
178 		/* Skip initializing the wrong priority */
179 		if (map_to_class(map) != class)
180 			continue;
181 
182 		/* Platform events are always bound, so set the bound flag */
183 		if (map->ev_num != SDEI_EVENT_0) {
184 			if (is_map_dynamic(map)) {
185 				assert(map->intr == SDEI_DYN_IRQ);
186 				assert(is_event_normal(map));
187 				num_dyn_priv_slots++;
188 			} else if (is_map_explicit(map)) {
189 				/*
190 				 * Explicit mappings don't have a backing
191 				 * SDEI interrupt, but verify that anyway.
192 				 */
193 				assert(map->intr == SDEI_DYN_IRQ);
194 			} else {
195 				/*
196 				 * Private mappings must be bound to private
197 				 * interrupt.
198 				 */
199 				assert(plat_ic_is_ppi((unsigned) map->intr) != 0);
200 				set_map_bound(map);
201 			}
202 		}
203 
204 		init_map(map);
205 	}
206 
207 	/* Ensure event 0 is in the mapping */
208 	assert(zero_found);
209 
210 	(void) sdei_cpu_on_init(NULL);
211 }
212 
213 /* SDEI dispatcher initialisation */
214 void sdei_init(void)
215 {
216 	sdei_class_init(SDEI_CRITICAL);
217 	sdei_class_init(SDEI_NORMAL);
218 
219 	/* Register priority level handlers */
220 	ehf_register_priority_handler(PLAT_SDEI_CRITICAL_PRI,
221 			sdei_intr_handler);
222 	ehf_register_priority_handler(PLAT_SDEI_NORMAL_PRI,
223 			sdei_intr_handler);
224 }
225 
226 /* Populate SDEI event entry */
227 static void set_sdei_entry(sdei_entry_t *se, uint64_t ep, uint64_t arg,
228 		unsigned int flags, uint64_t affinity)
229 {
230 	assert(se != NULL);
231 
232 	se->ep = ep;
233 	se->arg = arg;
234 	se->affinity = (affinity & MPIDR_AFFINITY_MASK);
235 	se->reg_flags = flags;
236 }
237 
238 static uint64_t sdei_version(void)
239 {
240 	return MAKE_SDEI_VERSION(MAJOR_VERSION, MINOR_VERSION, VENDOR_VERSION);
241 }
242 
243 /* Validate flags and MPIDR values for REGISTER and ROUTING_SET calls */
244 static int validate_flags(uint64_t flags, uint64_t mpidr)
245 {
246 	/* Validate flags */
247 	switch (flags) {
248 	case SDEI_REGF_RM_PE:
249 		if (!is_valid_affinity(mpidr))
250 			return SDEI_EINVAL;
251 		break;
252 	case SDEI_REGF_RM_ANY:
253 		break;
254 	default:
255 		/* Unknown flags */
256 		return SDEI_EINVAL;
257 	}
258 
259 	return 0;
260 }
261 
262 /* Set routing of an SDEI event */
263 static int sdei_event_routing_set(int ev_num, uint64_t flags, uint64_t mpidr)
264 {
265 	int ret;
266 	unsigned int routing;
267 	sdei_ev_map_t *map;
268 	sdei_entry_t *se;
269 
270 	ret = validate_flags(flags, mpidr);
271 	if (ret != 0)
272 		return ret;
273 
274 	/* Check if valid event number */
275 	map = find_event_map(ev_num);
276 	if (map == NULL)
277 		return SDEI_EINVAL;
278 
279 	/* The event must not be private */
280 	if (is_event_private(map))
281 		return SDEI_EINVAL;
282 
283 	se = get_event_entry(map);
284 
285 	sdei_map_lock(map);
286 
287 	if (!is_map_bound(map) || is_event_private(map)) {
288 		ret = SDEI_EINVAL;
289 		goto finish;
290 	}
291 
292 	if (!can_sdei_state_trans(se, DO_ROUTING)) {
293 		ret = SDEI_EDENY;
294 		goto finish;
295 	}
296 
297 	/* Choose appropriate routing */
298 	routing = (unsigned int) ((flags == SDEI_REGF_RM_ANY) ?
299 		INTR_ROUTING_MODE_ANY : INTR_ROUTING_MODE_PE);
300 
301 	/* Update event registration flag */
302 	se->reg_flags = (unsigned int) flags;
303 
304 	/*
305 	 * ROUTING_SET is permissible only when event composite state is
306 	 * 'registered, disabled, and not running'. This means that the
307 	 * interrupt is currently disabled, and not active.
308 	 */
309 	plat_ic_set_spi_routing(map->intr, routing, (u_register_t) mpidr);
310 
311 finish:
312 	sdei_map_unlock(map);
313 
314 	return ret;
315 }
316 
317 /* Register handler and argument for an SDEI event */
318 static int64_t sdei_event_register(int ev_num, uint64_t ep, uint64_t arg,
319 		uint64_t flags, uint64_t mpidr)
320 {
321 	int ret;
322 	unsigned int routing;
323 	sdei_entry_t *se;
324 	sdei_ev_map_t *map;
325 	sdei_state_t backup_state;
326 
327 	if ((ep == 0U) || (plat_sdei_validate_entry_point(
328 					ep, sdei_client_el()) != 0)) {
329 		return SDEI_EINVAL;
330 	}
331 
332 	ret = validate_flags(flags, mpidr);
333 	if (ret != 0)
334 		return ret;
335 
336 	/* Check if valid event number */
337 	map = find_event_map(ev_num);
338 	if (map == NULL)
339 		return SDEI_EINVAL;
340 
341 	/* Private events always target the PE */
342 	if (is_event_private(map))
343 		flags = SDEI_REGF_RM_PE;
344 
345 	se = get_event_entry(map);
346 
347 	/*
348 	 * Even though register operation is per-event (additionally for private
349 	 * events, registration is required individually), it has to be
350 	 * serialised with respect to bind/release, which are global operations.
351 	 * So we hold the lock throughout, unconditionally.
352 	 */
353 	sdei_map_lock(map);
354 
355 	backup_state = se->state;
356 	if (!can_sdei_state_trans(se, DO_REGISTER))
357 		goto fallback;
358 
359 	/*
360 	 * When registering for dynamic events, make sure it's been bound
361 	 * already. This has to be the case as, without binding, the client
362 	 * can't know about the event number to register for.
363 	 */
364 	if (is_map_dynamic(map) && !is_map_bound(map))
365 		goto fallback;
366 
367 	if (is_event_private(map)) {
368 		/* Multiple calls to register are possible for private events */
369 		assert(map->reg_count >= 0);
370 	} else {
371 		/* Only single call to register is possible for shared events */
372 		assert(map->reg_count == 0);
373 	}
374 
375 	if (is_map_bound(map)) {
376 		/* Meanwhile, did any PE ACK the interrupt? */
377 		if (plat_ic_get_interrupt_active(map->intr) != 0U)
378 			goto fallback;
379 
380 		/* The interrupt must currently owned by Non-secure */
381 		if (plat_ic_get_interrupt_type(map->intr) != INTR_TYPE_NS)
382 			goto fallback;
383 
384 		/*
385 		 * Disable forwarding of new interrupt triggers to CPU
386 		 * interface.
387 		 */
388 		plat_ic_disable_interrupt(map->intr);
389 
390 		/*
391 		 * Any events that are triggered after register and before
392 		 * enable should remain pending. Clear any previous interrupt
393 		 * triggers which are pending (except for SGIs). This has no
394 		 * affect on level-triggered interrupts.
395 		 */
396 		if (ev_num != SDEI_EVENT_0)
397 			plat_ic_clear_interrupt_pending(map->intr);
398 
399 		/* Map interrupt to EL3 and program the correct priority */
400 		plat_ic_set_interrupt_type(map->intr, INTR_TYPE_EL3);
401 
402 		/* Program the appropriate interrupt priority */
403 		plat_ic_set_interrupt_priority(map->intr, sdei_event_priority(map));
404 
405 		/*
406 		 * Set the routing mode for shared event as requested. We
407 		 * already ensure that shared events get bound to SPIs.
408 		 */
409 		if (is_event_shared(map)) {
410 			routing = (unsigned int) ((flags == SDEI_REGF_RM_ANY) ?
411 				INTR_ROUTING_MODE_ANY : INTR_ROUTING_MODE_PE);
412 			plat_ic_set_spi_routing(map->intr, routing,
413 					(u_register_t) mpidr);
414 		}
415 	}
416 
417 	/* Populate event entries */
418 	set_sdei_entry(se, ep, arg, (unsigned int) flags, mpidr);
419 
420 	/* Increment register count */
421 	map->reg_count++;
422 
423 	sdei_map_unlock(map);
424 
425 	return 0;
426 
427 fallback:
428 	/* Reinstate previous state */
429 	se->state = backup_state;
430 
431 	sdei_map_unlock(map);
432 
433 	return SDEI_EDENY;
434 }
435 
436 /* Enable SDEI event */
437 static int64_t sdei_event_enable(int ev_num)
438 {
439 	sdei_ev_map_t *map;
440 	sdei_entry_t *se;
441 	int ret;
442 	bool before, after;
443 
444 	/* Check if valid event number */
445 	map = find_event_map(ev_num);
446 	if (map == NULL)
447 		return SDEI_EINVAL;
448 
449 	se = get_event_entry(map);
450 	ret = SDEI_EDENY;
451 
452 	if (is_event_shared(map))
453 		sdei_map_lock(map);
454 
455 	before = GET_EV_STATE(se, ENABLED);
456 	if (!can_sdei_state_trans(se, DO_ENABLE))
457 		goto finish;
458 	after = GET_EV_STATE(se, ENABLED);
459 
460 	/*
461 	 * Enable interrupt for bound events only if there's a change in enabled
462 	 * state.
463 	 */
464 	if (is_map_bound(map) && (!before && after))
465 		plat_ic_enable_interrupt(map->intr);
466 
467 	ret = 0;
468 
469 finish:
470 	if (is_event_shared(map))
471 		sdei_map_unlock(map);
472 
473 	return ret;
474 }
475 
476 /* Disable SDEI event */
477 static int sdei_event_disable(int ev_num)
478 {
479 	sdei_ev_map_t *map;
480 	sdei_entry_t *se;
481 	int ret;
482 	bool before, after;
483 
484 	/* Check if valid event number */
485 	map = find_event_map(ev_num);
486 	if (map == NULL)
487 		return SDEI_EINVAL;
488 
489 	se = get_event_entry(map);
490 	ret = SDEI_EDENY;
491 
492 	if (is_event_shared(map))
493 		sdei_map_lock(map);
494 
495 	before = GET_EV_STATE(se, ENABLED);
496 	if (!can_sdei_state_trans(se, DO_DISABLE))
497 		goto finish;
498 	after = GET_EV_STATE(se, ENABLED);
499 
500 	/*
501 	 * Disable interrupt for bound events only if there's a change in
502 	 * enabled state.
503 	 */
504 	if (is_map_bound(map) && (before && !after))
505 		plat_ic_disable_interrupt(map->intr);
506 
507 	ret = 0;
508 
509 finish:
510 	if (is_event_shared(map))
511 		sdei_map_unlock(map);
512 
513 	return ret;
514 }
515 
516 /* Query SDEI event information */
517 static int64_t sdei_event_get_info(int ev_num, int info)
518 {
519 	sdei_entry_t *se;
520 	sdei_ev_map_t *map;
521 
522 	uint64_t flags;
523 	bool registered;
524 	uint64_t affinity;
525 
526 	/* Check if valid event number */
527 	map = find_event_map(ev_num);
528 	if (map == NULL)
529 		return SDEI_EINVAL;
530 
531 	se = get_event_entry(map);
532 
533 	if (is_event_shared(map))
534 		sdei_map_lock(map);
535 
536 	/* Sample state under lock */
537 	registered = GET_EV_STATE(se, REGISTERED);
538 	flags = se->reg_flags;
539 	affinity = se->affinity;
540 
541 	if (is_event_shared(map))
542 		sdei_map_unlock(map);
543 
544 	switch (info) {
545 	case SDEI_INFO_EV_TYPE:
546 		return is_event_shared(map);
547 
548 	case SDEI_INFO_EV_NOT_SIGNALED:
549 		return !is_event_signalable(map);
550 
551 	case SDEI_INFO_EV_PRIORITY:
552 		return is_event_critical(map);
553 
554 	case SDEI_INFO_EV_ROUTING_MODE:
555 		if (!is_event_shared(map))
556 			return SDEI_EINVAL;
557 		if (!registered)
558 			return SDEI_EDENY;
559 		return (flags == SDEI_REGF_RM_PE);
560 
561 	case SDEI_INFO_EV_ROUTING_AFF:
562 		if (!is_event_shared(map))
563 			return SDEI_EINVAL;
564 		if (!registered)
565 			return SDEI_EDENY;
566 		if (flags != SDEI_REGF_RM_PE)
567 			return SDEI_EINVAL;
568 		return affinity;
569 
570 	default:
571 		return SDEI_EINVAL;
572 	}
573 }
574 
575 /* Unregister an SDEI event */
576 static int sdei_event_unregister(int ev_num)
577 {
578 	int ret = 0;
579 	sdei_entry_t *se;
580 	sdei_ev_map_t *map;
581 
582 	/* Check if valid event number */
583 	map = find_event_map(ev_num);
584 	if (map == NULL)
585 		return SDEI_EINVAL;
586 
587 	se = get_event_entry(map);
588 
589 	/*
590 	 * Even though unregister operation is per-event (additionally for
591 	 * private events, unregistration is required individually), it has to
592 	 * be serialised with respect to bind/release, which are global
593 	 * operations.  So we hold the lock throughout, unconditionally.
594 	 */
595 	sdei_map_lock(map);
596 
597 	if (!can_sdei_state_trans(se, DO_UNREGISTER)) {
598 		/*
599 		 * Even if the call is invalid, and the handler is running (for
600 		 * example, having unregistered from a running handler earlier),
601 		 * return pending error code; otherwise, return deny.
602 		 */
603 		ret = GET_EV_STATE(se, RUNNING) ? SDEI_EPEND : SDEI_EDENY;
604 
605 		goto finish;
606 	}
607 
608 	map->reg_count--;
609 	if (is_event_private(map)) {
610 		/* Multiple calls to register are possible for private events */
611 		assert(map->reg_count >= 0);
612 	} else {
613 		/* Only single call to register is possible for shared events */
614 		assert(map->reg_count == 0);
615 	}
616 
617 	if (is_map_bound(map)) {
618 		plat_ic_disable_interrupt(map->intr);
619 
620 		/*
621 		 * Clear pending interrupt. Skip for SGIs as they may not be
622 		 * cleared on interrupt controllers.
623 		 */
624 		if (ev_num != SDEI_EVENT_0)
625 			plat_ic_clear_interrupt_pending(map->intr);
626 
627 		assert(plat_ic_get_interrupt_type(map->intr) == INTR_TYPE_EL3);
628 		plat_ic_set_interrupt_type(map->intr, INTR_TYPE_NS);
629 		plat_ic_set_interrupt_priority(map->intr, LOWEST_INTR_PRIORITY);
630 	}
631 
632 	clear_event_entries(se);
633 
634 	/*
635 	 * If the handler is running at the time of unregister, return the
636 	 * pending error code.
637 	 */
638 	if (GET_EV_STATE(se, RUNNING))
639 		ret = SDEI_EPEND;
640 
641 finish:
642 	sdei_map_unlock(map);
643 
644 	return ret;
645 }
646 
647 /* Query status of an SDEI event */
648 static int sdei_event_status(int ev_num)
649 {
650 	sdei_ev_map_t *map;
651 	sdei_entry_t *se;
652 	sdei_state_t state;
653 
654 	/* Check if valid event number */
655 	map = find_event_map(ev_num);
656 	if (map == NULL)
657 		return SDEI_EINVAL;
658 
659 	se = get_event_entry(map);
660 
661 	if (is_event_shared(map))
662 		sdei_map_lock(map);
663 
664 	/* State value directly maps to the expected return format */
665 	state = se->state;
666 
667 	if (is_event_shared(map))
668 		sdei_map_unlock(map);
669 
670 	return (int) state;
671 }
672 
673 /* Bind an SDEI event to an interrupt */
674 static int sdei_interrupt_bind(unsigned int intr_num)
675 {
676 	sdei_ev_map_t *map;
677 	bool retry = true, shared_mapping;
678 
679 	/* SGIs are not allowed to be bound */
680 	if (plat_ic_is_sgi(intr_num) != 0)
681 		return SDEI_EINVAL;
682 
683 	shared_mapping = (plat_ic_is_spi(intr_num) != 0);
684 	do {
685 		/*
686 		 * Bail out if there is already an event for this interrupt,
687 		 * either platform-defined or dynamic.
688 		 */
689 		map = find_event_map_by_intr(intr_num, shared_mapping);
690 		if (map != NULL) {
691 			if (is_map_dynamic(map)) {
692 				if (is_map_bound(map)) {
693 					/*
694 					 * Dynamic event, already bound. Return
695 					 * event number.
696 					 */
697 					return map->ev_num;
698 				}
699 			} else {
700 				/* Binding non-dynamic event */
701 				return SDEI_EINVAL;
702 			}
703 		}
704 
705 		/*
706 		 * The interrupt is not bound yet. Try to find a free slot to
707 		 * bind it. Free dynamic mappings have their interrupt set as
708 		 * SDEI_DYN_IRQ.
709 		 */
710 		map = find_event_map_by_intr(SDEI_DYN_IRQ, shared_mapping);
711 		if (map == NULL)
712 			return SDEI_ENOMEM;
713 
714 		/* The returned mapping must be dynamic */
715 		assert(is_map_dynamic(map));
716 
717 		/*
718 		 * We cannot assert for bound maps here, as we might be racing
719 		 * with another bind.
720 		 */
721 
722 		/* The requested interrupt must already belong to NS */
723 		if (plat_ic_get_interrupt_type(intr_num) != INTR_TYPE_NS)
724 			return SDEI_EDENY;
725 
726 		/*
727 		 * Interrupt programming and ownership transfer are deferred
728 		 * until register.
729 		 */
730 
731 		sdei_map_lock(map);
732 		if (!is_map_bound(map)) {
733 			map->intr = intr_num;
734 			set_map_bound(map);
735 			retry = false;
736 		}
737 		sdei_map_unlock(map);
738 	} while (retry);
739 
740 	return map->ev_num;
741 }
742 
743 /* Release a bound SDEI event previously to an interrupt */
744 static int sdei_interrupt_release(int ev_num)
745 {
746 	int ret = 0;
747 	sdei_ev_map_t *map;
748 	sdei_entry_t *se;
749 
750 	/* Check if valid event number */
751 	map = find_event_map(ev_num);
752 	if (map == NULL)
753 		return SDEI_EINVAL;
754 
755 	if (!is_map_dynamic(map))
756 		return SDEI_EINVAL;
757 
758 	se = get_event_entry(map);
759 
760 	sdei_map_lock(map);
761 
762 	/* Event must have been unregistered before release */
763 	if (map->reg_count != 0) {
764 		ret = SDEI_EDENY;
765 		goto finish;
766 	}
767 
768 	/*
769 	 * Interrupt release never causes the state to change. We only check
770 	 * whether it's permissible or not.
771 	 */
772 	if (!can_sdei_state_trans(se, DO_RELEASE)) {
773 		ret = SDEI_EDENY;
774 		goto finish;
775 	}
776 
777 	if (is_map_bound(map)) {
778 		/*
779 		 * Deny release if the interrupt is active, which means it's
780 		 * probably being acknowledged and handled elsewhere.
781 		 */
782 		if (plat_ic_get_interrupt_active(map->intr) != 0U) {
783 			ret = SDEI_EDENY;
784 			goto finish;
785 		}
786 
787 		/*
788 		 * Interrupt programming and ownership transfer are already done
789 		 * during unregister.
790 		 */
791 
792 		map->intr = SDEI_DYN_IRQ;
793 		clr_map_bound(map);
794 	} else {
795 		SDEI_LOG("Error release bound:%d cnt:%d\n", is_map_bound(map),
796 				map->reg_count);
797 		ret = SDEI_EINVAL;
798 	}
799 
800 finish:
801 	sdei_map_unlock(map);
802 
803 	return ret;
804 }
805 
806 /* Perform reset of private SDEI events */
807 static int sdei_private_reset(void)
808 {
809 	sdei_ev_map_t *map;
810 	int ret = 0, final_ret = 0;
811 	unsigned int i;
812 
813 	/* Unregister all private events */
814 	for_each_private_map(i, map) {
815 		/*
816 		 * The unregister can fail if the event is not registered, which
817 		 * is allowed, and a deny will be returned. But if the event is
818 		 * running or unregister pending, the call fails.
819 		 */
820 		ret = sdei_event_unregister(map->ev_num);
821 		if ((ret == SDEI_EPEND) && (final_ret == 0))
822 			final_ret = SDEI_EDENY;
823 	}
824 
825 	return final_ret;
826 }
827 
828 /* Perform reset of shared SDEI events */
829 static int sdei_shared_reset(void)
830 {
831 	const sdei_mapping_t *mapping;
832 	sdei_ev_map_t *map;
833 	int ret = 0, final_ret = 0;
834 	unsigned int i, j;
835 
836 	/* Unregister all shared events */
837 	for_each_shared_map(i, map) {
838 		/*
839 		 * The unregister can fail if the event is not registered, which
840 		 * is allowed, and a deny will be returned. But if the event is
841 		 * running or unregister pending, the call fails.
842 		 */
843 		ret = sdei_event_unregister(map->ev_num);
844 		if ((ret == SDEI_EPEND) && (final_ret == 0))
845 			final_ret = SDEI_EDENY;
846 	}
847 
848 	if (final_ret != 0)
849 		return final_ret;
850 
851 	/*
852 	 * Loop through both private and shared mappings, and release all
853 	 * bindings.
854 	 */
855 	for_each_mapping_type(i, mapping) {
856 		iterate_mapping(mapping, j, map) {
857 			/*
858 			 * Release bindings for mappings that are dynamic and
859 			 * bound.
860 			 */
861 			if (is_map_dynamic(map) && is_map_bound(map)) {
862 				/*
863 				 * Any failure to release would mean there is at
864 				 * least a PE registered for the event.
865 				 */
866 				ret = sdei_interrupt_release(map->ev_num);
867 				if ((ret != 0) && (final_ret == 0))
868 					final_ret = ret;
869 			}
870 		}
871 	}
872 
873 	return final_ret;
874 }
875 
876 /* Send a signal to another SDEI client PE */
877 static int sdei_signal(int ev_num, uint64_t target_pe)
878 {
879 	sdei_ev_map_t *map;
880 
881 	/* Only event 0 can be signalled */
882 	if (ev_num != SDEI_EVENT_0)
883 		return SDEI_EINVAL;
884 
885 	/* Find mapping for event 0 */
886 	map = find_event_map(SDEI_EVENT_0);
887 	if (map == NULL)
888 		return SDEI_EINVAL;
889 
890 	/* The event must be signalable */
891 	if (!is_event_signalable(map))
892 		return SDEI_EINVAL;
893 
894 	/* Validate target */
895 	if (plat_core_pos_by_mpidr(target_pe) < 0)
896 		return SDEI_EINVAL;
897 
898 	/* Raise SGI. Platform will validate target_pe */
899 	plat_ic_raise_el3_sgi((int) map->intr, (u_register_t) target_pe);
900 
901 	return 0;
902 }
903 
904 /* Query SDEI dispatcher features */
905 static uint64_t sdei_features(unsigned int feature)
906 {
907 	if (feature == SDEI_FEATURE_BIND_SLOTS) {
908 		return FEATURE_BIND_SLOTS(num_dyn_priv_slots,
909 				num_dyn_shrd_slots);
910 	}
911 
912 	return (uint64_t) SDEI_EINVAL;
913 }
914 
915 /* SDEI top level handler for servicing SMCs */
916 uint64_t sdei_smc_handler(uint32_t smc_fid,
917 			  uint64_t x1,
918 			  uint64_t x2,
919 			  uint64_t x3,
920 			  uint64_t x4,
921 			  void *cookie,
922 			  void *handle,
923 			  uint64_t flags)
924 {
925 
926 	uint64_t x5;
927 	unsigned int ss = (unsigned int) get_interrupt_src_ss(flags);
928 	int64_t ret;
929 	bool resume = false;
930 	cpu_context_t *ctx = handle;
931 	int ev_num = (int) x1;
932 
933 	if (ss != NON_SECURE)
934 		SMC_RET1(ctx, SMC_UNK);
935 
936 	/* Verify the caller EL */
937 	if (GET_EL(read_spsr_el3()) != sdei_client_el())
938 		SMC_RET1(ctx, SMC_UNK);
939 
940 	switch (smc_fid) {
941 	case SDEI_VERSION:
942 		SDEI_LOG("> VER\n");
943 		ret = (int64_t) sdei_version();
944 		SDEI_LOG("< VER:%llx\n", ret);
945 		SMC_RET1(ctx, ret);
946 
947 	case SDEI_EVENT_REGISTER:
948 		x5 = SMC_GET_GP(ctx, CTX_GPREG_X5);
949 		SDEI_LOG("> REG(n:%d e:%llx a:%llx f:%x m:%llx)\n", ev_num,
950 				x2, x3, (int) x4, x5);
951 		ret = sdei_event_register(ev_num, x2, x3, x4, x5);
952 		SDEI_LOG("< REG:%lld\n", ret);
953 		SMC_RET1(ctx, ret);
954 
955 	case SDEI_EVENT_ENABLE:
956 		SDEI_LOG("> ENABLE(n:%d)\n", (int) x1);
957 		ret = sdei_event_enable(ev_num);
958 		SDEI_LOG("< ENABLE:%lld\n", ret);
959 		SMC_RET1(ctx, ret);
960 
961 	case SDEI_EVENT_DISABLE:
962 		SDEI_LOG("> DISABLE(n:%d)\n", ev_num);
963 		ret = sdei_event_disable(ev_num);
964 		SDEI_LOG("< DISABLE:%lld\n", ret);
965 		SMC_RET1(ctx, ret);
966 
967 	case SDEI_EVENT_CONTEXT:
968 		SDEI_LOG("> CTX(p:%d):%lx\n", (int) x1, read_mpidr_el1());
969 		ret = sdei_event_context(ctx, (unsigned int) x1);
970 		SDEI_LOG("< CTX:%lld\n", ret);
971 		SMC_RET1(ctx, ret);
972 
973 	case SDEI_EVENT_COMPLETE_AND_RESUME:
974 		resume = true;
975 		/* Fallthrough */
976 
977 	case SDEI_EVENT_COMPLETE:
978 		SDEI_LOG("> COMPLETE(r:%u sta/ep:%llx):%lx\n",
979 				(unsigned int) resume, x1, read_mpidr_el1());
980 		ret = sdei_event_complete(resume, x1);
981 		SDEI_LOG("< COMPLETE:%llx\n", ret);
982 
983 		/*
984 		 * Set error code only if the call failed. If the call
985 		 * succeeded, we discard the dispatched context, and restore the
986 		 * interrupted context to a pristine condition, and therefore
987 		 * shouldn't be modified. We don't return to the caller in this
988 		 * case anyway.
989 		 */
990 		if (ret != 0)
991 			SMC_RET1(ctx, ret);
992 
993 		SMC_RET0(ctx);
994 
995 	case SDEI_EVENT_STATUS:
996 		SDEI_LOG("> STAT(n:%d)\n", ev_num);
997 		ret = sdei_event_status(ev_num);
998 		SDEI_LOG("< STAT:%lld\n", ret);
999 		SMC_RET1(ctx, ret);
1000 
1001 	case SDEI_EVENT_GET_INFO:
1002 		SDEI_LOG("> INFO(n:%d, %d)\n", ev_num, (int) x2);
1003 		ret = sdei_event_get_info(ev_num, (int) x2);
1004 		SDEI_LOG("< INFO:%lld\n", ret);
1005 		SMC_RET1(ctx, ret);
1006 
1007 	case SDEI_EVENT_UNREGISTER:
1008 		SDEI_LOG("> UNREG(n:%d)\n", ev_num);
1009 		ret = sdei_event_unregister(ev_num);
1010 		SDEI_LOG("< UNREG:%lld\n", ret);
1011 		SMC_RET1(ctx, ret);
1012 
1013 	case SDEI_PE_UNMASK:
1014 		SDEI_LOG("> UNMASK:%lx\n", read_mpidr_el1());
1015 		sdei_pe_unmask();
1016 		SDEI_LOG("< UNMASK:%d\n", 0);
1017 		SMC_RET1(ctx, 0);
1018 
1019 	case SDEI_PE_MASK:
1020 		SDEI_LOG("> MASK:%lx\n", read_mpidr_el1());
1021 		ret = sdei_pe_mask();
1022 		SDEI_LOG("< MASK:%lld\n", ret);
1023 		SMC_RET1(ctx, ret);
1024 
1025 	case SDEI_INTERRUPT_BIND:
1026 		SDEI_LOG("> BIND(%d)\n", (int) x1);
1027 		ret = sdei_interrupt_bind((unsigned int) x1);
1028 		SDEI_LOG("< BIND:%lld\n", ret);
1029 		SMC_RET1(ctx, ret);
1030 
1031 	case SDEI_INTERRUPT_RELEASE:
1032 		SDEI_LOG("> REL(%d)\n", ev_num);
1033 		ret = sdei_interrupt_release(ev_num);
1034 		SDEI_LOG("< REL:%lld\n", ret);
1035 		SMC_RET1(ctx, ret);
1036 
1037 	case SDEI_SHARED_RESET:
1038 		SDEI_LOG("> S_RESET():%lx\n", read_mpidr_el1());
1039 		ret = sdei_shared_reset();
1040 		SDEI_LOG("< S_RESET:%lld\n", ret);
1041 		SMC_RET1(ctx, ret);
1042 
1043 	case SDEI_PRIVATE_RESET:
1044 		SDEI_LOG("> P_RESET():%lx\n", read_mpidr_el1());
1045 		ret = sdei_private_reset();
1046 		SDEI_LOG("< P_RESET:%lld\n", ret);
1047 		SMC_RET1(ctx, ret);
1048 
1049 	case SDEI_EVENT_ROUTING_SET:
1050 		SDEI_LOG("> ROUTE_SET(n:%d f:%llx aff:%llx)\n", ev_num, x2, x3);
1051 		ret = sdei_event_routing_set(ev_num, x2, x3);
1052 		SDEI_LOG("< ROUTE_SET:%lld\n", ret);
1053 		SMC_RET1(ctx, ret);
1054 
1055 	case SDEI_FEATURES:
1056 		SDEI_LOG("> FTRS(f:%llx)\n", x1);
1057 		ret = (int64_t) sdei_features((unsigned int) x1);
1058 		SDEI_LOG("< FTRS:%llx\n", ret);
1059 		SMC_RET1(ctx, ret);
1060 
1061 	case SDEI_EVENT_SIGNAL:
1062 		SDEI_LOG("> SIGNAL(e:%d t:%llx)\n", ev_num, x2);
1063 		ret = sdei_signal(ev_num, x2);
1064 		SDEI_LOG("< SIGNAL:%lld\n", ret);
1065 		SMC_RET1(ctx, ret);
1066 
1067 	default:
1068 		/* Do nothing in default case */
1069 		break;
1070 	}
1071 
1072 	WARN("Unimplemented SDEI Call: 0x%x\n", smc_fid);
1073 	SMC_RET1(ctx, SMC_UNK);
1074 }
1075 
1076 /* Subscribe to PSCI CPU on to initialize per-CPU SDEI configuration */
1077 SUBSCRIBE_TO_EVENT(psci_cpu_on_finish, sdei_cpu_on_init);
1078