1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2017 Arm Ltd.
3 #define pr_fmt(fmt) "sdei: " fmt
6 #include <linux/acpi.h>
7 #include <linux/arm_sdei.h>
8 #include <linux/arm-smccc.h>
9 #include <linux/atomic.h>
10 #include <linux/bitops.h>
11 #include <linux/compiler.h>
12 #include <linux/cpuhotplug.h>
13 #include <linux/cpu.h>
14 #include <linux/cpu_pm.h>
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>
22 #include <linux/notifier.h>
24 #include <linux/of_platform.h>
25 #include <linux/percpu.h>
26 #include <linux/platform_device.h>
28 #include <linux/ptrace.h>
29 #include <linux/preempt.h>
30 #include <linux/reboot.h>
31 #include <linux/slab.h>
32 #include <linux/smp.h>
33 #include <linux/spinlock.h>
34 #include <linux/uaccess.h>
37 * The call to use to reach the firmware.
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);
44 /* entry point from firmware to arch asm code */
45 static unsigned long sdei_entry_point;
48 /* These three are protected by the sdei_list_lock */
49 struct list_head list;
57 /* This pointer is handed to firmware as the event argument. */
60 struct sdei_registered_event *registered;
62 /* CPU private events */
63 struct sdei_registered_event __percpu *private_registered;
67 /* Take the mutex for any API call or modification. Take the mutex first. */
68 static DEFINE_MUTEX(sdei_events_lock);
70 /* and then hold this when modifying the list */
71 static DEFINE_SPINLOCK(sdei_list_lock);
72 static LIST_HEAD(sdei_list);
74 /* Private events are registered/enabled via IPI passing one of these */
75 struct sdei_crosscall_args {
76 struct sdei_event *event;
81 #define CROSSCALL_INIT(arg, event) (arg.event = event, \
82 arg.first_error = 0, \
83 atomic_set(&arg.errors, 0))
85 static inline int sdei_do_cross_call(void *fn, struct sdei_event * event)
87 struct sdei_crosscall_args arg;
89 CROSSCALL_INIT(arg, event);
90 on_each_cpu(fn, &arg, true);
92 return arg.first_error;
96 sdei_cross_call_return(struct sdei_crosscall_args *arg, int err)
98 if (err && (atomic_inc_return(&arg->errors) == 1))
99 arg->first_error = err;
102 static int sdei_to_linux_errno(unsigned long sdei_err)
105 case SDEI_NOT_SUPPORTED:
107 case SDEI_INVALID_PARAMETERS:
113 case SDEI_OUT_OF_RESOURCE:
117 /* Not an error value ... */
122 * If x0 is any of these values, then the call failed, use sdei_to_linux_errno()
125 static int sdei_is_err(struct arm_smccc_res *res)
128 case SDEI_NOT_SUPPORTED:
129 case SDEI_INVALID_PARAMETERS:
132 case SDEI_OUT_OF_RESOURCE:
139 static int invoke_sdei_fn(unsigned long function_id, unsigned long arg0,
140 unsigned long arg1, unsigned long arg2,
141 unsigned long arg3, unsigned long arg4,
145 struct arm_smccc_res res;
147 if (sdei_firmware_call) {
148 sdei_firmware_call(function_id, arg0, arg1, arg2, arg3, arg4,
150 if (sdei_is_err(&res))
151 err = sdei_to_linux_errno(res.a0);
154 * !sdei_firmware_call means we failed to probe or called
155 * sdei_mark_interface_broken(). -EIO is not an error returned
156 * by sdei_to_linux_errno() and is used to suppress messages
160 res.a0 = SDEI_NOT_SUPPORTED;
169 static struct sdei_event *sdei_event_find(u32 event_num)
171 struct sdei_event *e, *found = NULL;
173 lockdep_assert_held(&sdei_events_lock);
175 spin_lock(&sdei_list_lock);
176 list_for_each_entry(e, &sdei_list, list) {
177 if (e->event_num == event_num) {
182 spin_unlock(&sdei_list_lock);
187 int sdei_api_event_context(u32 query, u64 *result)
189 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_CONTEXT, query, 0, 0, 0, 0,
192 NOKPROBE_SYMBOL(sdei_api_event_context);
194 static int sdei_api_event_get_info(u32 event, u32 info, u64 *result)
196 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_GET_INFO, event, info, 0,
200 static struct sdei_event *sdei_event_create(u32 event_num,
201 sdei_event_callback *cb,
206 struct sdei_event *event;
207 struct sdei_registered_event *reg;
209 lockdep_assert_held(&sdei_events_lock);
211 event = kzalloc(sizeof(*event), GFP_KERNEL);
213 return ERR_PTR(-ENOMEM);
215 INIT_LIST_HEAD(&event->list);
216 event->event_num = event_num;
218 err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY,
224 event->priority = result;
226 err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_TYPE,
232 event->type = result;
234 if (event->type == SDEI_EVENT_TYPE_SHARED) {
235 reg = kzalloc(sizeof(*reg), GFP_KERNEL);
238 return ERR_PTR(-ENOMEM);
241 reg->event_num = event_num;
242 reg->priority = event->priority;
245 reg->callback_arg = cb_arg;
246 event->registered = reg;
249 struct sdei_registered_event __percpu *regs;
251 regs = alloc_percpu(struct sdei_registered_event);
254 return ERR_PTR(-ENOMEM);
257 for_each_possible_cpu(cpu) {
258 reg = per_cpu_ptr(regs, cpu);
260 reg->event_num = event->event_num;
261 reg->priority = event->priority;
263 reg->callback_arg = cb_arg;
266 event->private_registered = regs;
269 if (sdei_event_find(event_num)) {
270 kfree(event->registered);
272 event = ERR_PTR(-EBUSY);
274 spin_lock(&sdei_list_lock);
275 list_add(&event->list, &sdei_list);
276 spin_unlock(&sdei_list_lock);
282 static void sdei_event_destroy(struct sdei_event *event)
284 lockdep_assert_held(&sdei_events_lock);
286 spin_lock(&sdei_list_lock);
287 list_del(&event->list);
288 spin_unlock(&sdei_list_lock);
290 if (event->type == SDEI_EVENT_TYPE_SHARED)
291 kfree(event->registered);
293 free_percpu(event->private_registered);
298 static int sdei_api_get_version(u64 *version)
300 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_VERSION, 0, 0, 0, 0, 0, version);
303 int sdei_mask_local_cpu(void)
307 WARN_ON_ONCE(preemptible());
309 err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_MASK, 0, 0, 0, 0, 0, NULL);
310 if (err && err != -EIO) {
311 pr_warn_once("failed to mask CPU[%u]: %d\n",
312 smp_processor_id(), err);
319 static void _ipi_mask_cpu(void *ignored)
321 sdei_mask_local_cpu();
324 int sdei_unmask_local_cpu(void)
328 WARN_ON_ONCE(preemptible());
330 err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PE_UNMASK, 0, 0, 0, 0, 0, NULL);
331 if (err && err != -EIO) {
332 pr_warn_once("failed to unmask CPU[%u]: %d\n",
333 smp_processor_id(), err);
340 static void _ipi_unmask_cpu(void *ignored)
342 sdei_unmask_local_cpu();
345 static void _ipi_private_reset(void *ignored)
349 err = invoke_sdei_fn(SDEI_1_0_FN_SDEI_PRIVATE_RESET, 0, 0, 0, 0, 0,
351 if (err && err != -EIO)
352 pr_warn_once("failed to reset CPU[%u]: %d\n",
353 smp_processor_id(), err);
356 static int sdei_api_shared_reset(void)
358 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_SHARED_RESET, 0, 0, 0, 0, 0,
362 static void sdei_mark_interface_broken(void)
364 pr_err("disabling SDEI firmware interface\n");
365 on_each_cpu(&_ipi_mask_cpu, NULL, true);
366 sdei_firmware_call = NULL;
369 static int sdei_platform_reset(void)
373 on_each_cpu(&_ipi_private_reset, NULL, true);
374 err = sdei_api_shared_reset();
376 pr_err("Failed to reset platform: %d\n", err);
377 sdei_mark_interface_broken();
383 static int sdei_api_event_enable(u32 event_num)
385 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_ENABLE, event_num, 0, 0, 0,
389 /* Called directly by the hotplug callbacks */
390 static void _local_event_enable(void *data)
393 struct sdei_crosscall_args *arg = data;
395 WARN_ON_ONCE(preemptible());
397 err = sdei_api_event_enable(arg->event->event_num);
399 sdei_cross_call_return(arg, err);
402 int sdei_event_enable(u32 event_num)
405 struct sdei_event *event;
407 mutex_lock(&sdei_events_lock);
408 event = sdei_event_find(event_num);
410 mutex_unlock(&sdei_events_lock);
414 spin_lock(&sdei_list_lock);
415 event->reenable = true;
416 spin_unlock(&sdei_list_lock);
418 if (event->type == SDEI_EVENT_TYPE_SHARED)
419 err = sdei_api_event_enable(event->event_num);
421 err = sdei_do_cross_call(_local_event_enable, event);
422 mutex_unlock(&sdei_events_lock);
426 EXPORT_SYMBOL(sdei_event_enable);
428 static int sdei_api_event_disable(u32 event_num)
430 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_DISABLE, event_num, 0, 0,
434 static void _ipi_event_disable(void *data)
437 struct sdei_crosscall_args *arg = data;
439 err = sdei_api_event_disable(arg->event->event_num);
441 sdei_cross_call_return(arg, err);
444 int sdei_event_disable(u32 event_num)
447 struct sdei_event *event;
449 mutex_lock(&sdei_events_lock);
450 event = sdei_event_find(event_num);
452 mutex_unlock(&sdei_events_lock);
456 spin_lock(&sdei_list_lock);
457 event->reenable = false;
458 spin_unlock(&sdei_list_lock);
460 if (event->type == SDEI_EVENT_TYPE_SHARED)
461 err = sdei_api_event_disable(event->event_num);
463 err = sdei_do_cross_call(_ipi_event_disable, event);
464 mutex_unlock(&sdei_events_lock);
468 EXPORT_SYMBOL(sdei_event_disable);
470 static int sdei_api_event_unregister(u32 event_num)
472 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_UNREGISTER, event_num, 0,
476 /* Called directly by the hotplug callbacks */
477 static void _local_event_unregister(void *data)
480 struct sdei_crosscall_args *arg = data;
482 WARN_ON_ONCE(preemptible());
484 err = sdei_api_event_unregister(arg->event->event_num);
486 sdei_cross_call_return(arg, err);
489 static int _sdei_event_unregister(struct sdei_event *event)
491 lockdep_assert_held(&sdei_events_lock);
493 spin_lock(&sdei_list_lock);
494 event->reregister = false;
495 event->reenable = false;
496 spin_unlock(&sdei_list_lock);
498 if (event->type == SDEI_EVENT_TYPE_SHARED)
499 return sdei_api_event_unregister(event->event_num);
501 return sdei_do_cross_call(_local_event_unregister, event);
504 int sdei_event_unregister(u32 event_num)
507 struct sdei_event *event;
511 mutex_lock(&sdei_events_lock);
512 event = sdei_event_find(event_num);
515 pr_warn("Event %u not registered\n", event_num);
520 err = _sdei_event_unregister(event);
524 sdei_event_destroy(event);
526 mutex_unlock(&sdei_events_lock);
530 EXPORT_SYMBOL(sdei_event_unregister);
533 * unregister events, but don't destroy them as they are re-registered by
534 * sdei_reregister_shared().
536 static int sdei_unregister_shared(void)
539 struct sdei_event *event;
541 mutex_lock(&sdei_events_lock);
542 spin_lock(&sdei_list_lock);
543 list_for_each_entry(event, &sdei_list, list) {
544 if (event->type != SDEI_EVENT_TYPE_SHARED)
547 err = _sdei_event_unregister(event);
551 spin_unlock(&sdei_list_lock);
552 mutex_unlock(&sdei_events_lock);
557 static int sdei_api_event_register(u32 event_num, unsigned long entry_point,
558 void *arg, u64 flags, u64 affinity)
560 return invoke_sdei_fn(SDEI_1_0_FN_SDEI_EVENT_REGISTER, event_num,
561 (unsigned long)entry_point, (unsigned long)arg,
562 flags, affinity, NULL);
565 /* Called directly by the hotplug callbacks */
566 static void _local_event_register(void *data)
569 struct sdei_registered_event *reg;
570 struct sdei_crosscall_args *arg = data;
572 WARN_ON(preemptible());
574 reg = per_cpu_ptr(arg->event->private_registered, smp_processor_id());
575 err = sdei_api_event_register(arg->event->event_num, sdei_entry_point,
578 sdei_cross_call_return(arg, err);
581 static int _sdei_event_register(struct sdei_event *event)
585 lockdep_assert_held(&sdei_events_lock);
587 spin_lock(&sdei_list_lock);
588 event->reregister = true;
589 spin_unlock(&sdei_list_lock);
591 if (event->type == SDEI_EVENT_TYPE_SHARED)
592 return sdei_api_event_register(event->event_num,
595 SDEI_EVENT_REGISTER_RM_ANY, 0);
598 err = sdei_do_cross_call(_local_event_register, event);
600 spin_lock(&sdei_list_lock);
601 event->reregister = false;
602 event->reenable = false;
603 spin_unlock(&sdei_list_lock);
605 sdei_do_cross_call(_local_event_unregister, event);
611 int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg)
614 struct sdei_event *event;
618 mutex_lock(&sdei_events_lock);
620 if (sdei_event_find(event_num)) {
621 pr_warn("Event %u already registered\n", event_num);
626 event = sdei_event_create(event_num, cb, arg);
628 err = PTR_ERR(event);
629 pr_warn("Failed to create event %u: %d\n", event_num,
634 err = _sdei_event_register(event);
636 sdei_event_destroy(event);
637 pr_warn("Failed to register event %u: %d\n", event_num,
641 mutex_unlock(&sdei_events_lock);
645 EXPORT_SYMBOL(sdei_event_register);
647 static int sdei_reregister_event(struct sdei_event *event)
651 lockdep_assert_held(&sdei_events_lock);
653 err = _sdei_event_register(event);
655 pr_err("Failed to re-register event %u\n", event->event_num);
656 sdei_event_destroy(event);
660 if (event->reenable) {
661 if (event->type == SDEI_EVENT_TYPE_SHARED)
662 err = sdei_api_event_enable(event->event_num);
664 err = sdei_do_cross_call(_local_event_enable, event);
668 pr_err("Failed to re-enable event %u\n", event->event_num);
673 static int sdei_reregister_shared(void)
676 struct sdei_event *event;
678 mutex_lock(&sdei_events_lock);
679 spin_lock(&sdei_list_lock);
680 list_for_each_entry(event, &sdei_list, list) {
681 if (event->type != SDEI_EVENT_TYPE_SHARED)
684 if (event->reregister) {
685 err = sdei_reregister_event(event);
690 spin_unlock(&sdei_list_lock);
691 mutex_unlock(&sdei_events_lock);
696 static int sdei_cpuhp_down(unsigned int cpu)
698 struct sdei_event *event;
699 struct sdei_crosscall_args arg;
701 /* un-register 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)
707 CROSSCALL_INIT(arg, event);
708 /* call the cross-call function locally... */
709 _local_event_unregister(&arg);
711 pr_err("Failed to unregister event %u: %d\n",
712 event->event_num, arg.first_error);
714 spin_unlock(&sdei_list_lock);
716 return sdei_mask_local_cpu();
719 static int sdei_cpuhp_up(unsigned int cpu)
721 struct sdei_event *event;
722 struct sdei_crosscall_args arg;
724 /* re-register/enable private events */
725 spin_lock(&sdei_list_lock);
726 list_for_each_entry(event, &sdei_list, list) {
727 if (event->type == SDEI_EVENT_TYPE_SHARED)
730 if (event->reregister) {
731 CROSSCALL_INIT(arg, event);
732 /* call the cross-call function locally... */
733 _local_event_register(&arg);
735 pr_err("Failed to re-register event %u: %d\n",
736 event->event_num, arg.first_error);
739 if (event->reenable) {
740 CROSSCALL_INIT(arg, event);
741 _local_event_enable(&arg);
743 pr_err("Failed to re-enable event %u: %d\n",
744 event->event_num, arg.first_error);
747 spin_unlock(&sdei_list_lock);
749 return sdei_unmask_local_cpu();
752 /* When entering idle, mask/unmask events for this cpu */
753 static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action,
760 rv = sdei_mask_local_cpu();
763 case CPU_PM_ENTER_FAILED:
764 rv = sdei_unmask_local_cpu();
771 return notifier_from_errno(rv);
776 static struct notifier_block sdei_pm_nb = {
777 .notifier_call = sdei_pm_notifier,
780 static int sdei_device_suspend(struct device *dev)
782 on_each_cpu(_ipi_mask_cpu, NULL, true);
787 static int sdei_device_resume(struct device *dev)
789 on_each_cpu(_ipi_unmask_cpu, NULL, true);
795 * We need all events to be reregistered when we resume from hibernate.
797 * The sequence is freeze->thaw. Reboot. freeze->restore. We unregister
798 * events during freeze, then re-register and re-enable them during thaw
801 static int sdei_device_freeze(struct device *dev)
805 /* unregister private events */
806 cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
808 err = sdei_unregister_shared();
815 static int sdei_device_thaw(struct device *dev)
819 /* re-register shared events */
820 err = sdei_reregister_shared();
822 pr_warn("Failed to re-register shared events...\n");
823 sdei_mark_interface_broken();
827 err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
828 &sdei_cpuhp_up, &sdei_cpuhp_down);
830 pr_warn("Failed to re-register CPU hotplug notifier...\n");
835 static int sdei_device_restore(struct device *dev)
839 err = sdei_platform_reset();
843 return sdei_device_thaw(dev);
846 static const struct dev_pm_ops sdei_pm_ops = {
847 .suspend = sdei_device_suspend,
848 .resume = sdei_device_resume,
849 .freeze = sdei_device_freeze,
850 .thaw = sdei_device_thaw,
851 .restore = sdei_device_restore,
855 * Mask all CPUs and unregister all events on panic, reboot or kexec.
857 static int sdei_reboot_notifier(struct notifier_block *nb, unsigned long action,
861 * We are going to reset the interface, after this there is no point
862 * doing work when we take CPUs offline.
864 cpuhp_remove_state(CPUHP_AP_ARM_SDEI_STARTING);
866 sdei_platform_reset();
871 static struct notifier_block sdei_reboot_nb = {
872 .notifier_call = sdei_reboot_notifier,
875 static void sdei_smccc_smc(unsigned long function_id,
876 unsigned long arg0, unsigned long arg1,
877 unsigned long arg2, unsigned long arg3,
878 unsigned long arg4, struct arm_smccc_res *res)
880 arm_smccc_smc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res);
883 static void sdei_smccc_hvc(unsigned long function_id,
884 unsigned long arg0, unsigned long arg1,
885 unsigned long arg2, unsigned long arg3,
886 unsigned long arg4, struct arm_smccc_res *res)
888 arm_smccc_hvc(function_id, arg0, arg1, arg2, arg3, arg4, 0, 0, res);
891 int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb,
892 sdei_event_callback *critical_cb)
897 sdei_event_callback *cb;
899 if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
902 event_num = ghes->generic->notify.vector;
903 if (event_num == 0) {
905 * Event 0 is reserved by the specification for
911 err = sdei_api_event_get_info(event_num, SDEI_EVENT_INFO_EV_PRIORITY,
916 if (result == SDEI_EVENT_PRIORITY_CRITICAL)
921 err = sdei_event_register(event_num, cb, ghes);
923 err = sdei_event_enable(event_num);
928 int sdei_unregister_ghes(struct ghes *ghes)
932 u32 event_num = ghes->generic->notify.vector;
936 if (!IS_ENABLED(CONFIG_ACPI_APEI_GHES))
940 * The event may be running on another CPU. Disable it
941 * to stop new events, then try to unregister a few times.
943 err = sdei_event_disable(event_num);
947 for (i = 0; i < 3; i++) {
948 err = sdei_event_unregister(event_num);
949 if (err != -EINPROGRESS)
958 static int sdei_get_conduit(struct platform_device *pdev)
961 struct device_node *np = pdev->dev.of_node;
963 sdei_firmware_call = NULL;
965 if (of_property_read_string(np, "method", &method)) {
966 pr_warn("missing \"method\" property\n");
967 return CONDUIT_INVALID;
970 if (!strcmp("hvc", method)) {
971 sdei_firmware_call = &sdei_smccc_hvc;
973 } else if (!strcmp("smc", method)) {
974 sdei_firmware_call = &sdei_smccc_smc;
978 pr_warn("invalid \"method\" property: %s\n", method);
979 } else if (IS_ENABLED(CONFIG_ACPI) && !acpi_disabled) {
980 if (acpi_psci_use_hvc()) {
981 sdei_firmware_call = &sdei_smccc_hvc;
984 sdei_firmware_call = &sdei_smccc_smc;
989 return CONDUIT_INVALID;
992 static int sdei_probe(struct platform_device *pdev)
998 conduit = sdei_get_conduit(pdev);
999 if (!sdei_firmware_call)
1002 err = sdei_api_get_version(&ver);
1003 if (err == -EOPNOTSUPP)
1004 pr_err("advertised but not implemented in platform firmware\n");
1006 pr_err("Failed to get SDEI version: %d\n", err);
1007 sdei_mark_interface_broken();
1011 pr_info("SDEIv%d.%d (0x%x) detected in firmware.\n",
1012 (int)SDEI_VERSION_MAJOR(ver), (int)SDEI_VERSION_MINOR(ver),
1013 (int)SDEI_VERSION_VENDOR(ver));
1015 if (SDEI_VERSION_MAJOR(ver) != 1) {
1016 pr_warn("Conflicting SDEI version detected.\n");
1017 sdei_mark_interface_broken();
1021 err = sdei_platform_reset();
1025 sdei_entry_point = sdei_arch_get_entry_point(conduit);
1026 if (!sdei_entry_point) {
1027 /* Not supported due to hardware or boot configuration */
1028 sdei_mark_interface_broken();
1032 err = cpu_pm_register_notifier(&sdei_pm_nb);
1034 pr_warn("Failed to register CPU PM notifier...\n");
1038 err = register_reboot_notifier(&sdei_reboot_nb);
1040 pr_warn("Failed to register reboot notifier...\n");
1044 err = cpuhp_setup_state(CPUHP_AP_ARM_SDEI_STARTING, "SDEI",
1045 &sdei_cpuhp_up, &sdei_cpuhp_down);
1047 pr_warn("Failed to register CPU hotplug notifier...\n");
1054 unregister_reboot_notifier(&sdei_reboot_nb);
1057 cpu_pm_unregister_notifier(&sdei_pm_nb);
1060 sdei_mark_interface_broken();
1064 static const struct of_device_id sdei_of_match[] = {
1065 { .compatible = "arm,sdei-1.0" },
1069 static struct platform_driver sdei_driver = {
1073 .of_match_table = sdei_of_match,
1075 .probe = sdei_probe,
1078 static bool __init sdei_present_dt(void)
1080 struct device_node *np, *fw_np;
1082 fw_np = of_find_node_by_name(NULL, "firmware");
1086 np = of_find_matching_node(fw_np, sdei_of_match);
1094 static bool __init sdei_present_acpi(void)
1097 struct platform_device *pdev;
1098 struct acpi_table_header *sdei_table_header;
1103 status = acpi_get_table(ACPI_SIG_SDEI, 0, &sdei_table_header);
1104 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
1105 const char *msg = acpi_format_exception(status);
1107 pr_info("Failed to get ACPI:SDEI table, %s\n", msg);
1109 if (ACPI_FAILURE(status))
1112 pdev = platform_device_register_simple(sdei_driver.driver.name, 0, NULL,
1120 static int __init sdei_init(void)
1122 if (sdei_present_dt() || sdei_present_acpi())
1123 platform_driver_register(&sdei_driver);
1129 * On an ACPI system SDEI needs to be ready before HEST:GHES tries to register
1130 * its events. ACPI is initialised from a subsys_initcall(), GHES is initialised
1131 * by device_initcall(). We want to be called in the middle.
1133 subsys_initcall_sync(sdei_init);
1135 int sdei_event_handler(struct pt_regs *regs,
1136 struct sdei_registered_event *arg)
1139 mm_segment_t orig_addr_limit;
1140 u32 event_num = arg->event_num;
1142 orig_addr_limit = get_fs();
1145 err = arg->callback(event_num, regs, arg->callback_arg);
1147 pr_err_ratelimited("event %u on CPU %u failed with error: %d\n",
1148 event_num, smp_processor_id(), err);
1150 set_fs(orig_addr_limit);
1154 NOKPROBE_SYMBOL(sdei_event_handler);