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ad6eb31e JM |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // Copyright (C) 2017 Arm Ltd. | |
3 | #define pr_fmt(fmt) "sdei: " fmt | |
4 | ||
f96935d3 | 5 | #include <acpi/ghes.h> |
ad6eb31e JM |
6 | #include <linux/acpi.h> |
7 | #include <linux/arm_sdei.h> | |
8 | #include <linux/arm-smccc.h> | |
f92b5462 | 9 | #include <linux/atomic.h> |
ad6eb31e JM |
10 | #include <linux/bitops.h> |
11 | #include <linux/compiler.h> | |
da351827 | 12 | #include <linux/cpuhotplug.h> |
f92b5462 | 13 | #include <linux/cpu.h> |
da351827 | 14 | #include <linux/cpu_pm.h> |
ad6eb31e JM |
15 | #include <linux/errno.h> |
16 | #include <linux/hardirq.h> | |
17 | #include <linux/kernel.h> | |
18 | #include <linux/kprobes.h> | |
19 | #include <linux/kvm_host.h> | |
20 | #include <linux/list.h> | |
21 | #include <linux/mutex.h> | |
da351827 | 22 | #include <linux/notifier.h> |
ad6eb31e JM |
23 | #include <linux/of.h> |
24 | #include <linux/of_platform.h> | |
25 | #include <linux/percpu.h> | |
26 | #include <linux/platform_device.h> | |
da351827 | 27 | #include <linux/pm.h> |
ad6eb31e JM |
28 | #include <linux/ptrace.h> |
29 | #include <linux/preempt.h> | |
da351827 | 30 | #include <linux/reboot.h> |
ad6eb31e JM |
31 | #include <linux/slab.h> |
32 | #include <linux/smp.h> | |
33 | #include <linux/spinlock.h> | |
34 | #include <linux/uaccess.h> | |
35 | ||
36 | /* | |
37 | * The call to use to reach the firmware. | |
38 | */ | |
39 | static asmlinkage void (*sdei_firmware_call)(unsigned long function_id, | |
40 | unsigned long arg0, unsigned long arg1, | |
41 | unsigned long arg2, unsigned long arg3, | |
42 | unsigned long arg4, struct arm_smccc_res *res); | |
43 | ||
44 | /* entry point from firmware to arch asm code */ | |
45 | static unsigned long sdei_entry_point; | |
46 | ||
47 | struct sdei_event { | |
da351827 | 48 | /* These three are protected by the sdei_list_lock */ |
ad6eb31e | 49 | struct list_head list; |
da351827 JM |
50 | bool reregister; |
51 | bool reenable; | |
52 | ||
ad6eb31e JM |
53 | u32 event_num; |
54 | u8 type; | |
55 | u8 priority; | |
56 | ||
57 | /* This pointer is handed to firmware as the event argument. */ | |
f92b5462 JM |
58 | union { |
59 | /* Shared events */ | |
60 | struct sdei_registered_event *registered; | |
61 | ||
62 | /* CPU private events */ | |
63 | struct sdei_registered_event __percpu *private_registered; | |
64 | }; | |
ad6eb31e JM |
65 | }; |
66 | ||
67 | /* Take the mutex for any API call or modification. Take the mutex first. */ | |
68 | static DEFINE_MUTEX(sdei_events_lock); | |
69 | ||
70 | /* and then hold this when modifying the list */ | |
71 | static DEFINE_SPINLOCK(sdei_list_lock); | |
72 | static LIST_HEAD(sdei_list); | |
73 | ||
f92b5462 JM |
74 | /* Private events are registered/enabled via IPI passing one of these */ |
75 | struct sdei_crosscall_args { | |
76 | struct sdei_event *event; | |
77 | atomic_t errors; | |
78 | int first_error; | |
79 | }; | |
80 | ||
81 | #define CROSSCALL_INIT(arg, event) (arg.event = event, \ | |
82 | arg.first_error = 0, \ | |
83 | atomic_set(&arg.errors, 0)) | |
84 | ||
85 | static inline int sdei_do_cross_call(void *fn, struct sdei_event * event) | |
86 | { | |
87 | struct sdei_crosscall_args arg; | |
88 | ||
89 | CROSSCALL_INIT(arg, event); | |
90 | on_each_cpu(fn, &arg, true); | |
91 | ||
92 | return arg.first_error; | |
93 | } | |
94 | ||
95 | static inline void | |
96 | sdei_cross_call_return(struct sdei_crosscall_args *arg, int err) | |
97 | { | |
98 | if (err && (atomic_inc_return(&arg->errors) == 1)) | |
99 | arg->first_error = err; | |
100 | } | |
101 | ||
ad6eb31e JM |
102 | static int sdei_to_linux_errno(unsigned long sdei_err) |
103 | { | |
104 | switch (sdei_err) { | |
105 | case SDEI_NOT_SUPPORTED: | |
106 | return -EOPNOTSUPP; | |
107 | case SDEI_INVALID_PARAMETERS: | |
108 | return -EINVAL; | |
109 | case SDEI_DENIED: | |
110 | return -EPERM; | |
111 | case SDEI_PENDING: | |
112 | return -EINPROGRESS; | |
113 | case SDEI_OUT_OF_RESOURCE: | |
114 | return -ENOMEM; | |
115 | } | |
116 | ||
5735f515 | 117 | return 0; |
ad6eb31e JM |
118 | } |
119 | ||
120 | static int invoke_sdei_fn(unsigned long function_id, unsigned long arg0, | |
121 | unsigned long arg1, unsigned long arg2, | |
122 | unsigned long arg3, unsigned long arg4, | |
123 | u64 *result) | |
124 | { | |
5735f515 | 125 | int err; |
ad6eb31e JM |
126 | struct arm_smccc_res res; |
127 | ||
128 | if (sdei_firmware_call) { | |
129 | sdei_firmware_call(function_id, arg0, arg1, arg2, arg3, arg4, | |
130 | &res); | |
5735f515 | 131 | err = sdei_to_linux_errno(res.a0); |
ad6eb31e JM |
132 | } else { |
133 | /* | |
134 | * !sdei_firmware_call means we failed to probe or called | |
135 | * sdei_mark_interface_broken(). -EIO is not an error returned | |
136 | * by sdei_to_linux_errno() and is used to suppress messages | |
137 | * from this driver. | |
138 | */ | |
139 | err = -EIO; | |
140 | res.a0 = SDEI_NOT_SUPPORTED; | |
141 | } | |
142 | ||
143 | if (result) | |
144 | *result = res.a0; | |
145 | ||
146 | return err; | |
147 | } | |
2f1d4e24 | 148 | NOKPROBE_SYMBOL(invoke_sdei_fn); |
ad6eb31e JM |
149 | |
150 | static struct sdei_event *sdei_event_find(u32 event_num) | |
151 | { | |
152 | struct sdei_event *e, *found = NULL; | |
153 | ||
154 | lockdep_assert_held(&sdei_events_lock); | |
155 | ||
156 | spin_lock(&sdei_list_lock); | |
157 | list_for_each_entry(e, &sdei_list, list) { | |
158 | if (e->event_num == event_num) { | |
159 | found = e; | |
160 | break; | |
161 | } | |
162 | } | |
163 | spin_unlock(&sdei_list_lock); | |
164 | ||
165 | return found; | |
166 | } | |
167 | ||
168 | int sdei_api_event_context(u32 query, u64 *result) | |
169 | { | |
170 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_CONTEXT, query, 0, 0, 0, 0, | |
171 | result); | |
172 | } | |
173 | NOKPROBE_SYMBOL(sdei_api_event_context); | |
174 | ||
175 | static int sdei_api_event_get_info(u32 event, u32 info, u64 *result) | |
176 | { | |
177 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_GET_INFO, event, info, 0, | |
178 | 0, 0, result); | |
179 | } | |
180 | ||
181 | static struct sdei_event *sdei_event_create(u32 event_num, | |
182 | sdei_event_callback *cb, | |
183 | void *cb_arg) | |
184 | { | |
185 | int err; | |
186 | u64 result; | |
187 | struct sdei_event *event; | |
188 | struct sdei_registered_event *reg; | |
189 | ||
190 | lockdep_assert_held(&sdei_events_lock); | |
191 | ||
192 | event = kzalloc(sizeof(*event), GFP_KERNEL); | |
11988424 GS |
193 | if (!event) { |
194 | err = -ENOMEM; | |
195 | goto fail; | |
196 | } | |
ad6eb31e JM |
197 | |
198 | INIT_LIST_HEAD(&event->list); | |
199 | event->event_num = event_num; | |
200 | ||
201 | err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY, | |
202 | &result); | |
11988424 GS |
203 | if (err) |
204 | goto fail; | |
ad6eb31e JM |
205 | event->priority = result; |
206 | ||
207 | err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_TYPE, | |
208 | &result); | |
11988424 GS |
209 | if (err) |
210 | goto fail; | |
ad6eb31e JM |
211 | event->type = result; |
212 | ||
213 | if (event->type == SDEI_EVENT_TYPE_SHARED) { | |
214 | reg = kzalloc(sizeof(*reg), GFP_KERNEL); | |
215 | if (!reg) { | |
11988424 GS |
216 | err = -ENOMEM; |
217 | goto fail; | |
ad6eb31e JM |
218 | } |
219 | ||
663c0e89 | 220 | reg->event_num = event->event_num; |
ad6eb31e JM |
221 | reg->priority = event->priority; |
222 | ||
223 | reg->callback = cb; | |
224 | reg->callback_arg = cb_arg; | |
225 | event->registered = reg; | |
f92b5462 JM |
226 | } else { |
227 | int cpu; | |
228 | struct sdei_registered_event __percpu *regs; | |
229 | ||
230 | regs = alloc_percpu(struct sdei_registered_event); | |
231 | if (!regs) { | |
11988424 GS |
232 | err = -ENOMEM; |
233 | goto fail; | |
f92b5462 JM |
234 | } |
235 | ||
236 | for_each_possible_cpu(cpu) { | |
237 | reg = per_cpu_ptr(regs, cpu); | |
238 | ||
239 | reg->event_num = event->event_num; | |
240 | reg->priority = event->priority; | |
241 | reg->callback = cb; | |
242 | reg->callback_arg = cb_arg; | |
243 | } | |
244 | ||
245 | event->private_registered = regs; | |
ad6eb31e JM |
246 | } |
247 | ||
f7d5ef0c LZ |
248 | spin_lock(&sdei_list_lock); |
249 | list_add(&event->list, &sdei_list); | |
250 | spin_unlock(&sdei_list_lock); | |
ad6eb31e JM |
251 | |
252 | return event; | |
11988424 GS |
253 | |
254 | fail: | |
255 | kfree(event); | |
256 | return ERR_PTR(err); | |
ad6eb31e JM |
257 | } |
258 | ||
c66d52b1 | 259 | static void sdei_event_destroy_llocked(struct sdei_event *event) |
ad6eb31e JM |
260 | { |
261 | lockdep_assert_held(&sdei_events_lock); | |
c66d52b1 | 262 | lockdep_assert_held(&sdei_list_lock); |
ad6eb31e | 263 | |
ad6eb31e | 264 | list_del(&event->list); |
ad6eb31e JM |
265 | |
266 | if (event->type == SDEI_EVENT_TYPE_SHARED) | |
267 | kfree(event->registered); | |
f92b5462 JM |
268 | else |
269 | free_percpu(event->private_registered); | |
ad6eb31e JM |
270 | |
271 | kfree(event); | |
272 | } | |
273 | ||
c66d52b1 LZ |
274 | static void sdei_event_destroy(struct sdei_event *event) |
275 | { | |
276 | spin_lock(&sdei_list_lock); | |
277 | sdei_event_destroy_llocked(event); | |
278 | spin_unlock(&sdei_list_lock); | |
279 | } | |
280 | ||
ad6eb31e JM |
281 | static int sdei_api_get_version(u64 *version) |
282 | { | |
283 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_VERSION, 0, 0, 0, 0, 0, version); | |
284 | } | |
285 | ||
286 | int sdei_mask_local_cpu(void) | |
287 | { | |
288 | int err; | |
289 | ||
290 | WARN_ON_ONCE(preemptible()); | |
291 | ||
292 | err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL); | |
293 | if (err && err != -EIO) { | |
294 | pr_warn_once("failed to mask CPU[%u]: %d\n", | |
295 | smp_processor_id(), err); | |
296 | return err; | |
297 | } | |
298 | ||
299 | return 0; | |
300 | } | |
301 | ||
302 | static void _ipi_mask_cpu(void *ignored) | |
303 | { | |
304 | sdei_mask_local_cpu(); | |
305 | } | |
306 | ||
307 | int sdei_unmask_local_cpu(void) | |
308 | { | |
309 | int err; | |
310 | ||
311 | WARN_ON_ONCE(preemptible()); | |
312 | ||
313 | err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL); | |
314 | if (err && err != -EIO) { | |
315 | pr_warn_once("failed to unmask CPU[%u]: %d\n", | |
316 | smp_processor_id(), err); | |
317 | return err; | |
318 | } | |
319 | ||
320 | return 0; | |
321 | } | |
322 | ||
323 | static void _ipi_unmask_cpu(void *ignored) | |
324 | { | |
325 | sdei_unmask_local_cpu(); | |
326 | } | |
327 | ||
328 | static void _ipi_private_reset(void *ignored) | |
329 | { | |
330 | int err; | |
331 | ||
332 | err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0, | |
333 | NULL); | |
334 | if (err && err != -EIO) | |
335 | pr_warn_once("failed to reset CPU[%u]: %d\n", | |
336 | smp_processor_id(), err); | |
337 | } | |
338 | ||
339 | static int sdei_api_shared_reset(void) | |
340 | { | |
341 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_SHARED_RESET, 0, 0, 0, 0, 0, | |
342 | NULL); | |
343 | } | |
344 | ||
345 | static void sdei_mark_interface_broken(void) | |
346 | { | |
347 | pr_err("disabling SDEI firmware interface\n"); | |
348 | on_each_cpu(&_ipi_mask_cpu, NULL, true); | |
349 | sdei_firmware_call = NULL; | |
350 | } | |
351 | ||
352 | static int sdei_platform_reset(void) | |
353 | { | |
354 | int err; | |
355 | ||
356 | on_each_cpu(&_ipi_private_reset, NULL, true); | |
357 | err = sdei_api_shared_reset(); | |
358 | if (err) { | |
359 | pr_err("Failed to reset platform: %d\n", err); | |
360 | sdei_mark_interface_broken(); | |
361 | } | |
362 | ||
363 | return err; | |
364 | } | |
365 | ||
366 | static int sdei_api_event_enable(u32 event_num) | |
367 | { | |
368 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_ENABLE, event_num, 0, 0, 0, | |
369 | 0, NULL); | |
370 | } | |
371 | ||
f92b5462 JM |
372 | /* Called directly by the hotplug callbacks */ |
373 | static void _local_event_enable(void *data) | |
374 | { | |
375 | int err; | |
376 | struct sdei_crosscall_args *arg = data; | |
377 | ||
378 | WARN_ON_ONCE(preemptible()); | |
379 | ||
380 | err = sdei_api_event_enable(arg->event->event_num); | |
381 | ||
382 | sdei_cross_call_return(arg, err); | |
383 | } | |
384 | ||
ad6eb31e JM |
385 | int sdei_event_enable(u32 event_num) |
386 | { | |
387 | int err = -EINVAL; | |
388 | struct sdei_event *event; | |
389 | ||
390 | mutex_lock(&sdei_events_lock); | |
391 | event = sdei_event_find(event_num); | |
392 | if (!event) { | |
393 | mutex_unlock(&sdei_events_lock); | |
394 | return -ENOENT; | |
395 | } | |
396 | ||
da351827 | 397 | |
54f529a6 | 398 | cpus_read_lock(); |
ad6eb31e JM |
399 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
400 | err = sdei_api_event_enable(event->event_num); | |
f92b5462 JM |
401 | else |
402 | err = sdei_do_cross_call(_local_event_enable, event); | |
54f529a6 JM |
403 | |
404 | if (!err) { | |
405 | spin_lock(&sdei_list_lock); | |
406 | event->reenable = true; | |
407 | spin_unlock(&sdei_list_lock); | |
408 | } | |
409 | cpus_read_unlock(); | |
ad6eb31e JM |
410 | mutex_unlock(&sdei_events_lock); |
411 | ||
412 | return err; | |
413 | } | |
ad6eb31e JM |
414 | |
415 | static int sdei_api_event_disable(u32 event_num) | |
416 | { | |
417 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_DISABLE, event_num, 0, 0, | |
418 | 0, 0, NULL); | |
419 | } | |
420 | ||
f92b5462 JM |
421 | static void _ipi_event_disable(void *data) |
422 | { | |
423 | int err; | |
424 | struct sdei_crosscall_args *arg = data; | |
425 | ||
426 | err = sdei_api_event_disable(arg->event->event_num); | |
427 | ||
428 | sdei_cross_call_return(arg, err); | |
429 | } | |
430 | ||
ad6eb31e JM |
431 | int sdei_event_disable(u32 event_num) |
432 | { | |
433 | int err = -EINVAL; | |
434 | struct sdei_event *event; | |
435 | ||
436 | mutex_lock(&sdei_events_lock); | |
437 | event = sdei_event_find(event_num); | |
438 | if (!event) { | |
439 | mutex_unlock(&sdei_events_lock); | |
440 | return -ENOENT; | |
441 | } | |
442 | ||
da351827 JM |
443 | spin_lock(&sdei_list_lock); |
444 | event->reenable = false; | |
445 | spin_unlock(&sdei_list_lock); | |
446 | ||
ad6eb31e JM |
447 | if (event->type == SDEI_EVENT_TYPE_SHARED) |
448 | err = sdei_api_event_disable(event->event_num); | |
f92b5462 JM |
449 | else |
450 | err = sdei_do_cross_call(_ipi_event_disable, event); | |
ad6eb31e JM |
451 | mutex_unlock(&sdei_events_lock); |
452 | ||
453 | return err; | |
454 | } | |
ad6eb31e JM |
455 | |
456 | static int sdei_api_event_unregister(u32 event_num) | |
457 | { | |
458 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_UNREGISTER, event_num, 0, | |
459 | 0, 0, 0, NULL); | |
460 | } | |
461 | ||
f92b5462 JM |
462 | /* Called directly by the hotplug callbacks */ |
463 | static void _local_event_unregister(void *data) | |
464 | { | |
465 | int err; | |
466 | struct sdei_crosscall_args *arg = data; | |
467 | ||
468 | WARN_ON_ONCE(preemptible()); | |
469 | ||
470 | err = sdei_api_event_unregister(arg->event->event_num); | |
471 | ||
472 | sdei_cross_call_return(arg, err); | |
473 | } | |
474 | ||
ad6eb31e JM |
475 | static int _sdei_event_unregister(struct sdei_event *event) |
476 | { | |
477 | lockdep_assert_held(&sdei_events_lock); | |
478 | ||
479 | if (event->type == SDEI_EVENT_TYPE_SHARED) | |
480 | return sdei_api_event_unregister(event->event_num); | |
481 | ||
f92b5462 | 482 | return sdei_do_cross_call(_local_event_unregister, event); |
ad6eb31e JM |
483 | } |
484 | ||
485 | int sdei_event_unregister(u32 event_num) | |
486 | { | |
487 | int err; | |
488 | struct sdei_event *event; | |
489 | ||
490 | WARN_ON(in_nmi()); | |
491 | ||
492 | mutex_lock(&sdei_events_lock); | |
493 | event = sdei_event_find(event_num); | |
b06146b6 GS |
494 | if (!event) { |
495 | pr_warn("Event %u not registered\n", event_num); | |
496 | err = -ENOENT; | |
497 | goto unlock; | |
498 | } | |
ad6eb31e | 499 | |
b06146b6 GS |
500 | spin_lock(&sdei_list_lock); |
501 | event->reregister = false; | |
502 | event->reenable = false; | |
503 | spin_unlock(&sdei_list_lock); | |
6ded0b61 | 504 | |
b06146b6 GS |
505 | err = _sdei_event_unregister(event); |
506 | if (err) | |
507 | goto unlock; | |
ad6eb31e | 508 | |
b06146b6 GS |
509 | sdei_event_destroy(event); |
510 | unlock: | |
ad6eb31e JM |
511 | mutex_unlock(&sdei_events_lock); |
512 | ||
513 | return err; | |
514 | } | |
ad6eb31e | 515 | |
da351827 JM |
516 | /* |
517 | * unregister events, but don't destroy them as they are re-registered by | |
518 | * sdei_reregister_shared(). | |
519 | */ | |
520 | static int sdei_unregister_shared(void) | |
521 | { | |
522 | int err = 0; | |
523 | struct sdei_event *event; | |
524 | ||
525 | mutex_lock(&sdei_events_lock); | |
526 | spin_lock(&sdei_list_lock); | |
527 | list_for_each_entry(event, &sdei_list, list) { | |
528 | if (event->type != SDEI_EVENT_TYPE_SHARED) | |
529 | continue; | |
530 | ||
531 | err = _sdei_event_unregister(event); | |
532 | if (err) | |
533 | break; | |
534 | } | |
535 | spin_unlock(&sdei_list_lock); | |
536 | mutex_unlock(&sdei_events_lock); | |
537 | ||
538 | return err; | |
539 | } | |
540 | ||
ad6eb31e JM |
541 | static int sdei_api_event_register(u32 event_num, unsigned long entry_point, |
542 | void *arg, u64 flags, u64 affinity) | |
543 | { | |
544 | return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_REGISTER, event_num, | |
545 | (unsigned long)entry_point, (unsigned long)arg, | |
546 | flags, affinity, NULL); | |
547 | } | |
548 | ||
f92b5462 JM |
549 | /* Called directly by the hotplug callbacks */ |
550 | static void _local_event_register(void *data) | |
551 | { | |
552 | int err; | |
553 | struct sdei_registered_event *reg; | |
554 | struct sdei_crosscall_args *arg = data; | |
555 | ||
556 | WARN_ON(preemptible()); | |
557 | ||
558 | reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id()); | |
559 | err = sdei_api_event_register(arg->event->event_num, sdei_entry_point, | |
560 | reg, 0, 0); | |
561 | ||
562 | sdei_cross_call_return(arg, err); | |
563 | } | |
564 | ||
ad6eb31e JM |
565 | static int _sdei_event_register(struct sdei_event *event) |
566 | { | |
f92b5462 JM |
567 | int err; |
568 | ||
ad6eb31e JM |
569 | lockdep_assert_held(&sdei_events_lock); |
570 | ||
571 | if (event->type == SDEI_EVENT_TYPE_SHARED) | |
572 | return sdei_api_event_register(event->event_num, | |
573 | sdei_entry_point, | |
574 | event->registered, | |
575 | SDEI_EVENT_REGISTER_RM_ANY, 0); | |
576 | ||
f92b5462 | 577 | err = sdei_do_cross_call(_local_event_register, event); |
6ded0b61 | 578 | if (err) |
f92b5462 | 579 | sdei_do_cross_call(_local_event_unregister, event); |
f92b5462 JM |
580 | |
581 | return err; | |
ad6eb31e JM |
582 | } |
583 | ||
584 | int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg) | |
585 | { | |
586 | int err; | |
587 | struct sdei_event *event; | |
588 | ||
589 | WARN_ON(in_nmi()); | |
590 | ||
591 | mutex_lock(&sdei_events_lock); | |
1bbc7551 GS |
592 | if (sdei_event_find(event_num)) { |
593 | pr_warn("Event %u already registered\n", event_num); | |
594 | err = -EBUSY; | |
595 | goto unlock; | |
596 | } | |
ad6eb31e | 597 | |
1bbc7551 GS |
598 | event = sdei_event_create(event_num, cb, arg); |
599 | if (IS_ERR(event)) { | |
600 | err = PTR_ERR(event); | |
601 | pr_warn("Failed to create event %u: %d\n", event_num, err); | |
602 | goto unlock; | |
603 | } | |
ad6eb31e | 604 | |
1bbc7551 GS |
605 | cpus_read_lock(); |
606 | err = _sdei_event_register(event); | |
607 | if (err) { | |
608 | sdei_event_destroy(event); | |
609 | pr_warn("Failed to register event %u: %d\n", event_num, err); | |
610 | goto cpu_unlock; | |
611 | } | |
ad6eb31e | 612 | |
1bbc7551 GS |
613 | spin_lock(&sdei_list_lock); |
614 | event->reregister = true; | |
615 | spin_unlock(&sdei_list_lock); | |
616 | cpu_unlock: | |
617 | cpus_read_unlock(); | |
618 | unlock: | |
619 | mutex_unlock(&sdei_events_lock); | |
ad6eb31e JM |
620 | return err; |
621 | } | |
ad6eb31e | 622 | |
c66d52b1 | 623 | static int sdei_reregister_event_llocked(struct sdei_event *event) |
da351827 JM |
624 | { |
625 | int err; | |
626 | ||
627 | lockdep_assert_held(&sdei_events_lock); | |
c66d52b1 | 628 | lockdep_assert_held(&sdei_list_lock); |
da351827 JM |
629 | |
630 | err = _sdei_event_register(event); | |
631 | if (err) { | |
632 | pr_err("Failed to re-register event %u\n", event->event_num); | |
c66d52b1 | 633 | sdei_event_destroy_llocked(event); |
da351827 JM |
634 | return err; |
635 | } | |
636 | ||
637 | if (event->reenable) { | |
638 | if (event->type == SDEI_EVENT_TYPE_SHARED) | |
639 | err = sdei_api_event_enable(event->event_num); | |
f92b5462 JM |
640 | else |
641 | err = sdei_do_cross_call(_local_event_enable, event); | |
da351827 JM |
642 | } |
643 | ||
644 | if (err) | |
645 | pr_err("Failed to re-enable event %u\n", event->event_num); | |
646 | ||
647 | return err; | |
648 | } | |
649 | ||
650 | static int sdei_reregister_shared(void) | |
651 | { | |
652 | int err = 0; | |
653 | struct sdei_event *event; | |
654 | ||
655 | mutex_lock(&sdei_events_lock); | |
656 | spin_lock(&sdei_list_lock); | |
657 | list_for_each_entry(event, &sdei_list, list) { | |
658 | if (event->type != SDEI_EVENT_TYPE_SHARED) | |
659 | continue; | |
660 | ||
661 | if (event->reregister) { | |
c66d52b1 | 662 | err = sdei_reregister_event_llocked(event); |
da351827 JM |
663 | if (err) |
664 | break; | |
665 | } | |
666 | } | |
667 | spin_unlock(&sdei_list_lock); | |
668 | mutex_unlock(&sdei_events_lock); | |
669 | ||
670 | return err; | |
671 | } | |
672 | ||
f92b5462 JM |
673 | static int sdei_cpuhp_down(unsigned int cpu) |
674 | { | |
675 | struct sdei_event *event; | |
676 | struct sdei_crosscall_args arg; | |
677 | ||
678 | /* un-register private events */ | |
679 | spin_lock(&sdei_list_lock); | |
680 | list_for_each_entry(event, &sdei_list, list) { | |
681 | if (event->type == SDEI_EVENT_TYPE_SHARED) | |
682 | continue; | |
683 | ||
684 | CROSSCALL_INIT(arg, event); | |
685 | /* call the cross-call function locally... */ | |
686 | _local_event_unregister(&arg); | |
687 | if (arg.first_error) | |
688 | pr_err("Failed to unregister event %u: %d\n", | |
689 | event->event_num, arg.first_error); | |
690 | } | |
691 | spin_unlock(&sdei_list_lock); | |
692 | ||
693 | return sdei_mask_local_cpu(); | |
694 | } | |
695 | ||
696 | static int sdei_cpuhp_up(unsigned int cpu) | |
697 | { | |
698 | struct sdei_event *event; | |
699 | struct sdei_crosscall_args arg; | |
700 | ||
701 | /* re-register/enable private events */ | |
702 | spin_lock(&sdei_list_lock); | |
703 | list_for_each_entry(event, &sdei_list, list) { | |
704 | if (event->type == SDEI_EVENT_TYPE_SHARED) | |
705 | continue; | |
706 | ||
707 | if (event->reregister) { | |
708 | CROSSCALL_INIT(arg, event); | |
709 | /* call the cross-call function locally... */ | |
710 | _local_event_register(&arg); | |
711 | if (arg.first_error) | |
712 | pr_err("Failed to re-register event %u: %d\n", | |
713 | event->event_num, arg.first_error); | |
714 | } | |
715 | ||
716 | if (event->reenable) { | |
717 | CROSSCALL_INIT(arg, event); | |
718 | _local_event_enable(&arg); | |
719 | if (arg.first_error) | |
720 | pr_err("Failed to re-enable event %u: %d\n", | |
721 | event->event_num, arg.first_error); | |
722 | } | |
723 | } | |
724 | spin_unlock(&sdei_list_lock); | |
725 | ||
726 | return sdei_unmask_local_cpu(); | |
727 | } | |
728 | ||
da351827 JM |
729 | /* When entering idle, mask/unmask events for this cpu */ |
730 | static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action, | |
731 | void *data) | |
732 | { | |
733 | int rv; | |
734 | ||
735 | switch (action) { | |
736 | case CPU_PM_ENTER: | |
737 | rv = sdei_mask_local_cpu(); | |
738 | break; | |
739 | case CPU_PM_EXIT: | |
740 | case CPU_PM_ENTER_FAILED: | |
741 | rv = sdei_unmask_local_cpu(); | |
742 | break; | |
743 | default: | |
744 | return NOTIFY_DONE; | |
745 | } | |
746 | ||
747 | if (rv) | |
748 | return notifier_from_errno(rv); | |
749 | ||
750 | return NOTIFY_OK; | |
751 | } | |
752 | ||
753 | static struct notifier_block sdei_pm_nb = { | |
754 | .notifier_call = sdei_pm_notifier, | |
755 | }; | |
756 | ||
757 | static int sdei_device_suspend(struct device *dev) | |
758 | { | |
759 | on_each_cpu(_ipi_mask_cpu, NULL, true); | |
760 | ||
761 | return 0; | |
762 | } | |
763 | ||
764 | static int sdei_device_resume(struct device *dev) | |
765 | { | |
766 | on_each_cpu(_ipi_unmask_cpu, NULL, true); | |
767 | ||
768 | return 0; | |
769 | } | |
770 | ||
771 | /* | |
772 | * We need all events to be reregistered when we resume from hibernate. | |
773 | * | |
774 | * The sequence is freeze->thaw. Reboot. freeze->restore. We unregister | |
775 | * events during freeze, then re-register and re-enable them during thaw | |
776 | * and restore. | |
777 | */ | |
778 | static int sdei_device_freeze(struct device *dev) | |
779 | { | |
780 | int err; | |
781 | ||
f92b5462 | 782 | /* unregister private events */ |
da351827 JM |
783 | cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING); |
784 | ||
785 | err = sdei_unregister_shared(); | |
786 | if (err) | |
787 | return err; | |
788 | ||
789 | return 0; | |
790 | } | |
791 | ||
792 | static int sdei_device_thaw(struct device *dev) | |
793 | { | |
794 | int err; | |
795 | ||
796 | /* re-register shared events */ | |
797 | err = sdei_reregister_shared(); | |
798 | if (err) { | |
799 | pr_warn("Failed to re-register shared events...\n"); | |
800 | sdei_mark_interface_broken(); | |
801 | return err; | |
802 | } | |
803 | ||
804 | err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI", | |
805 | &sdei_cpuhp_up, &sdei_cpuhp_down); | |
806 | if (err) | |
807 | pr_warn("Failed to re-register CPU hotplug notifier...\n"); | |
808 | ||
809 | return err; | |
810 | } | |
811 | ||
812 | static int sdei_device_restore(struct device *dev) | |
813 | { | |
814 | int err; | |
815 | ||
816 | err = sdei_platform_reset(); | |
817 | if (err) | |
818 | return err; | |
819 | ||
820 | return sdei_device_thaw(dev); | |
821 | } | |
822 | ||
823 | static const struct dev_pm_ops sdei_pm_ops = { | |
824 | .suspend = sdei_device_suspend, | |
825 | .resume = sdei_device_resume, | |
826 | .freeze = sdei_device_freeze, | |
827 | .thaw = sdei_device_thaw, | |
828 | .restore = sdei_device_restore, | |
829 | }; | |
830 | ||
831 | /* | |
832 | * Mask all CPUs and unregister all events on panic, reboot or kexec. | |
833 | */ | |
834 | static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action, | |
835 | void *data) | |
836 | { | |
837 | /* | |
838 | * We are going to reset the interface, after this there is no point | |
839 | * doing work when we take CPUs offline. | |
840 | */ | |
841 | cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING); | |
842 | ||
843 | sdei_platform_reset(); | |
844 | ||
845 | return NOTIFY_OK; | |
846 | } | |
847 | ||
848 | static struct notifier_block sdei_reboot_nb = { | |
849 | .notifier_call = sdei_reboot_notifier, | |
850 | }; | |
851 | ||
ad6eb31e JM |
852 | static void sdei_smccc_smc(unsigned long function_id, |
853 | unsigned long arg0, unsigned long arg1, | |
854 | unsigned long arg2, unsigned long arg3, | |
855 | unsigned long arg4, struct arm_smccc_res *res) | |
856 | { | |
857 | arm_smccc_smc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res); | |
858 | } | |
2f1d4e24 | 859 | NOKPROBE_SYMBOL(sdei_smccc_smc); |
ad6eb31e JM |
860 | |
861 | static void sdei_smccc_hvc(unsigned long function_id, | |
862 | unsigned long arg0, unsigned long arg1, | |
863 | unsigned long arg2, unsigned long arg3, | |
864 | unsigned long arg4, struct arm_smccc_res *res) | |
865 | { | |
866 | arm_smccc_hvc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res); | |
867 | } | |
2f1d4e24 | 868 | NOKPROBE_SYMBOL(sdei_smccc_hvc); |
ad6eb31e | 869 | |
f96935d3 JM |
870 | int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb, |
871 | sdei_event_callback *critical_cb) | |
872 | { | |
873 | int err; | |
874 | u64 result; | |
875 | u32 event_num; | |
876 | sdei_event_callback *cb; | |
877 | ||
878 | if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES)) | |
879 | return -EOPNOTSUPP; | |
880 | ||
881 | event_num = ghes->generic->notify.vector; | |
882 | if (event_num == 0) { | |
883 | /* | |
884 | * Event 0 is reserved by the specification for | |
885 | * SDEI_EVENT_SIGNAL. | |
886 | */ | |
887 | return -EINVAL; | |
888 | } | |
889 | ||
890 | err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY, | |
891 | &result); | |
892 | if (err) | |
893 | return err; | |
894 | ||
895 | if (result == SDEI_EVENT_PRIORITY_CRITICAL) | |
896 | cb = critical_cb; | |
897 | else | |
898 | cb = normal_cb; | |
899 | ||
900 | err = sdei_event_register(event_num, cb, ghes); | |
901 | if (!err) | |
902 | err = sdei_event_enable(event_num); | |
903 | ||
904 | return err; | |
905 | } | |
906 | ||
907 | int sdei_unregister_ghes(struct ghes *ghes) | |
908 | { | |
909 | int i; | |
910 | int err; | |
911 | u32 event_num = ghes->generic->notify.vector; | |
912 | ||
913 | might_sleep(); | |
914 | ||
915 | if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES)) | |
916 | return -EOPNOTSUPP; | |
917 | ||
918 | /* | |
919 | * The event may be running on another CPU. Disable it | |
920 | * to stop new events, then try to unregister a few times. | |
921 | */ | |
922 | err = sdei_event_disable(event_num); | |
923 | if (err) | |
924 | return err; | |
925 | ||
926 | for (i = 0; i < 3; i++) { | |
927 | err = sdei_event_unregister(event_num); | |
928 | if (err != -EINPROGRESS) | |
929 | break; | |
930 | ||
931 | schedule(); | |
932 | } | |
933 | ||
934 | return err; | |
935 | } | |
936 | ||
ad6eb31e JM |
937 | static int sdei_get_conduit(struct platform_device *pdev) |
938 | { | |
939 | const char *method; | |
940 | struct device_node *np = pdev->dev.of_node; | |
941 | ||
942 | sdei_firmware_call = NULL; | |
943 | if (np) { | |
944 | if (of_property_read_string(np, "method", &method)) { | |
945 | pr_warn("missing \"method\" property\n"); | |
e6ea4651 | 946 | return SMCCC_CONDUIT_NONE; |
ad6eb31e JM |
947 | } |
948 | ||
949 | if (!strcmp("hvc", method)) { | |
950 | sdei_firmware_call = &sdei_smccc_hvc; | |
e6ea4651 | 951 | return SMCCC_CONDUIT_HVC; |
ad6eb31e JM |
952 | } else if (!strcmp("smc", method)) { |
953 | sdei_firmware_call = &sdei_smccc_smc; | |
e6ea4651 | 954 | return SMCCC_CONDUIT_SMC; |
ad6eb31e JM |
955 | } |
956 | ||
957 | pr_warn("invalid \"method\" property: %s\n", method); | |
bc110fd3 | 958 | } else if (!acpi_disabled) { |
677a60bd JM |
959 | if (acpi_psci_use_hvc()) { |
960 | sdei_firmware_call = &sdei_smccc_hvc; | |
e6ea4651 | 961 | return SMCCC_CONDUIT_HVC; |
677a60bd JM |
962 | } else { |
963 | sdei_firmware_call = &sdei_smccc_smc; | |
e6ea4651 | 964 | return SMCCC_CONDUIT_SMC; |
677a60bd | 965 | } |
ad6eb31e JM |
966 | } |
967 | ||
e6ea4651 | 968 | return SMCCC_CONDUIT_NONE; |
ad6eb31e JM |
969 | } |
970 | ||
971 | static int sdei_probe(struct platform_device *pdev) | |
972 | { | |
973 | int err; | |
974 | u64 ver = 0; | |
975 | int conduit; | |
976 | ||
977 | conduit = sdei_get_conduit(pdev); | |
978 | if (!sdei_firmware_call) | |
979 | return 0; | |
980 | ||
981 | err = sdei_api_get_version(&ver); | |
ad6eb31e JM |
982 | if (err) { |
983 | pr_err("Failed to get SDEI version: %d\n", err); | |
984 | sdei_mark_interface_broken(); | |
985 | return err; | |
986 | } | |
987 | ||
988 | pr_info("SDEIv%d.%d (0x%x) detected in firmware.\n", | |
989 | (int)SDEI_VERSION_MAJOR(ver), (int)SDEI_VERSION_MINOR(ver), | |
990 | (int)SDEI_VERSION_VENDOR(ver)); | |
991 | ||
992 | if (SDEI_VERSION_MAJOR(ver) != 1) { | |
993 | pr_warn("Conflicting SDEI version detected.\n"); | |
994 | sdei_mark_interface_broken(); | |
995 | return -EINVAL; | |
996 | } | |
997 | ||
998 | err = sdei_platform_reset(); | |
999 | if (err) | |
1000 | return err; | |
1001 | ||
1002 | sdei_entry_point = sdei_arch_get_entry_point(conduit); | |
1003 | if (!sdei_entry_point) { | |
1004 | /* Not supported due to hardware or boot configuration */ | |
1005 | sdei_mark_interface_broken(); | |
1006 | return 0; | |
1007 | } | |
1008 | ||
da351827 JM |
1009 | err = cpu_pm_register_notifier(&sdei_pm_nb); |
1010 | if (err) { | |
1011 | pr_warn("Failed to register CPU PM notifier...\n"); | |
1012 | goto error; | |
1013 | } | |
1014 | ||
1015 | err = register_reboot_notifier(&sdei_reboot_nb); | |
1016 | if (err) { | |
1017 | pr_warn("Failed to register reboot notifier...\n"); | |
1018 | goto remove_cpupm; | |
1019 | } | |
1020 | ||
1021 | err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI", | |
1022 | &sdei_cpuhp_up, &sdei_cpuhp_down); | |
1023 | if (err) { | |
1024 | pr_warn("Failed to register CPU hotplug notifier...\n"); | |
1025 | goto remove_reboot; | |
1026 | } | |
ad6eb31e JM |
1027 | |
1028 | return 0; | |
da351827 JM |
1029 | |
1030 | remove_reboot: | |
1031 | unregister_reboot_notifier(&sdei_reboot_nb); | |
1032 | ||
1033 | remove_cpupm: | |
1034 | cpu_pm_unregister_notifier(&sdei_pm_nb); | |
1035 | ||
1036 | error: | |
1037 | sdei_mark_interface_broken(); | |
1038 | return err; | |
ad6eb31e JM |
1039 | } |
1040 | ||
1041 | static const struct of_device_id sdei_of_match[] = { | |
1042 | { .compatible = "arm,sdei-1.0" }, | |
1043 | {} | |
1044 | }; | |
1045 | ||
1046 | static struct platform_driver sdei_driver = { | |
1047 | .driver = { | |
1048 | .name = "sdei", | |
da351827 | 1049 | .pm = &sdei_pm_ops, |
ad6eb31e JM |
1050 | .of_match_table = sdei_of_match, |
1051 | }, | |
1052 | .probe = sdei_probe, | |
1053 | }; | |
1054 | ||
677a60bd JM |
1055 | static bool __init sdei_present_acpi(void) |
1056 | { | |
1057 | acpi_status status; | |
677a60bd JM |
1058 | struct acpi_table_header *sdei_table_header; |
1059 | ||
1060 | if (acpi_disabled) | |
1061 | return false; | |
1062 | ||
1063 | status = acpi_get_table(ACPI_SIG_SDEI, 0, &sdei_table_header); | |
1064 | if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { | |
1065 | const char *msg = acpi_format_exception(status); | |
1066 | ||
1067 | pr_info("Failed to get ACPI:SDEI table, %s\n", msg); | |
1068 | } | |
1069 | if (ACPI_FAILURE(status)) | |
1070 | return false; | |
1071 | ||
70e6352a HG |
1072 | acpi_put_table(sdei_table_header); |
1073 | ||
677a60bd JM |
1074 | return true; |
1075 | } | |
1076 | ||
ad6eb31e JM |
1077 | static int __init sdei_init(void) |
1078 | { | |
10fd7c42 GS |
1079 | struct platform_device *pdev; |
1080 | int ret; | |
1081 | ||
1082 | ret = platform_driver_register(&sdei_driver); | |
1083 | if (ret || !sdei_present_acpi()) | |
1084 | return ret; | |
1085 | ||
1086 | pdev = platform_device_register_simple(sdei_driver.driver.name, | |
1087 | 0, NULL, 0); | |
63627cae GS |
1088 | if (IS_ERR(pdev)) { |
1089 | ret = PTR_ERR(pdev); | |
1090 | platform_driver_unregister(&sdei_driver); | |
1091 | pr_info("Failed to register ACPI:SDEI platform device %d\n", | |
1092 | ret); | |
1093 | } | |
caf2cd61 SH |
1094 | |
1095 | return ret; | |
ad6eb31e JM |
1096 | } |
1097 | ||
677a60bd JM |
1098 | /* |
1099 | * On an ACPI system SDEI needs to be ready before HEST:GHES tries to register | |
1100 | * its events. ACPI is initialised from a subsys_initcall(), GHES is initialised | |
1101 | * by device_initcall(). We want to be called in the middle. | |
1102 | */ | |
ad6eb31e JM |
1103 | subsys_initcall_sync(sdei_init); |
1104 | ||
1105 | int sdei_event_handler(struct pt_regs *regs, | |
1106 | struct sdei_registered_event *arg) | |
1107 | { | |
1108 | int err; | |
1109 | mm_segment_t orig_addr_limit; | |
1110 | u32 event_num = arg->event_num; | |
1111 | ||
472de63b JM |
1112 | /* |
1113 | * Save restore 'fs'. | |
1114 | * The architecture's entry code save/restores 'fs' when taking an | |
1115 | * exception from the kernel. This ensures addr_limit isn't inherited | |
1116 | * if you interrupted something that allowed the uaccess routines to | |
1117 | * access kernel memory. | |
1118 | * Do the same here because this doesn't come via the same entry code. | |
1119 | */ | |
3d13f313 | 1120 | orig_addr_limit = force_uaccess_begin(); |
ad6eb31e JM |
1121 | |
1122 | err = arg->callback(event_num, regs, arg->callback_arg); | |
1123 | if (err) | |
1124 | pr_err_ratelimited("event %u on CPU %u failed with error: %d\n", | |
1125 | event_num, smp_processor_id(), err); | |
1126 | ||
3d13f313 | 1127 | force_uaccess_end(orig_addr_limit); |
ad6eb31e JM |
1128 | |
1129 | return err; | |
1130 | } | |
1131 | NOKPROBE_SYMBOL(sdei_event_handler); |