1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2017 Arm Ltd.
3 #ifndef __LINUX_ARM_SDEI_H
4 #define __LINUX_ARM_SDEI_H
5
6 #include <uapi/linux/arm_sdei.h>
7
8 #include <acpi/ghes.h>
9
10 #ifdef CONFIG_ARM_SDE_INTERFACE
11 #include <asm/sdei.h>
12 #endif
13
14 /* Arch code should override this to set the entry point from firmware... */
15 #ifndef sdei_arch_get_entry_point
16 #define sdei_arch_get_entry_point(conduit) (0)
17 #endif
18
19 /*
20 * When an event occurs sdei_event_handler() will call a user-provided callback
21 * like this in NMI context on the CPU that received the event.
22 */
23 typedef int (sdei_event_callback)(u32 event, struct pt_regs *regs, void *arg);
24
25 /*
26 * Register your callback to claim an event. The event must be described
27 * by firmware.
28 */
29 int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg);
30
31 /*
32 * Calls to sdei_event_unregister() may return EINPROGRESS. Keep calling
33 * it until it succeeds.
34 */
35 int sdei_event_unregister(u32 event_num);
36
37 int sdei_event_enable(u32 event_num);
38 int sdei_event_disable(u32 event_num);
39
40 /* GHES register/unregister helpers */
41 int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb,
42 sdei_event_callback *critical_cb);
43 int sdei_unregister_ghes(struct ghes *ghes);
44
45 #ifdef CONFIG_ARM_SDE_INTERFACE
46 /* For use by arch code when CPU hotplug notifiers are not appropriate. */
47 int sdei_mask_local_cpu(void);
48 int sdei_unmask_local_cpu(void);
49 void __init sdei_init(void);
50 void sdei_handler_abort(void);
51 #else
sdei_mask_local_cpu(void)52 static inline int sdei_mask_local_cpu(void) { return 0; }
sdei_unmask_local_cpu(void)53 static inline int sdei_unmask_local_cpu(void) { return 0; }
sdei_init(void)54 static inline void sdei_init(void) { }
sdei_handler_abort(void)55 static inline void sdei_handler_abort(void) { }
56 #endif /* CONFIG_ARM_SDE_INTERFACE */
57
58
59 /*
60 * This struct represents an event that has been registered. The driver
61 * maintains a list of all events, and which ones are registered. (Private
62 * events have one entry in the list, but are registered on each CPU).
63 * A pointer to this struct is passed to firmware, and back to the event
64 * handler. The event handler can then use this to invoke the registered
65 * callback, without having to walk the list.
66 *
67 * For CPU private events, this structure is per-cpu.
68 */
69 struct sdei_registered_event {
70 /* For use by arch code: */
71 struct pt_regs interrupted_regs;
72
73 sdei_event_callback *callback;
74 void *callback_arg;
75 u32 event_num;
76 u8 priority;
77 };
78
79 /* The arch code entry point should then call this when an event arrives. */
80 int notrace sdei_event_handler(struct pt_regs *regs,
81 struct sdei_registered_event *arg);
82
83 /* arch code may use this to retrieve the extra registers. */
84 int sdei_api_event_context(u32 query, u64 *result);
85
86 #endif /* __LINUX_ARM_SDEI_H */
87