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
8enum sdei_conduit_types {
9 CONDUIT_INVALID = 0,
10 CONDUIT_SMC,
11 CONDUIT_HVC,
12};
13
14#include <acpi/ghes.h>
15
16#ifdef CONFIG_ARM_SDE_INTERFACE
17#include <asm/sdei.h>
18#endif
19
20/* Arch code should override this to set the entry point from firmware... */
21#ifndef sdei_arch_get_entry_point
22#define sdei_arch_get_entry_point(conduit) (0)
23#endif
24
25/*
26 * When an event occurs sdei_event_handler() will call a user-provided callback
27 * like this in NMI context on the CPU that received the event.
28 */
29typedef int (sdei_event_callback)(u32 event, struct pt_regs *regs, void *arg);
30
31/*
32 * Register your callback to claim an event. The event must be described
33 * by firmware.
34 */
35int sdei_event_register(u32 event_num, sdei_event_callback *cb, void *arg);
36
37/*
38 * Calls to sdei_event_unregister() may return EINPROGRESS. Keep calling
39 * it until it succeeds.
40 */
41int sdei_event_unregister(u32 event_num);
42
43int sdei_event_enable(u32 event_num);
44int sdei_event_disable(u32 event_num);
45
46/* GHES register/unregister helpers */
47int sdei_register_ghes(struct ghes *ghes, sdei_event_callback *normal_cb,
48 sdei_event_callback *critical_cb);
49int sdei_unregister_ghes(struct ghes *ghes);
50
51#ifdef CONFIG_ARM_SDE_INTERFACE
52/* For use by arch code when CPU hotplug notifiers are not appropriate. */
53int sdei_mask_local_cpu(void);
54int sdei_unmask_local_cpu(void);
55#else
56static inline int sdei_mask_local_cpu(void) { return 0; }
57static inline int sdei_unmask_local_cpu(void) { return 0; }
58#endif /* CONFIG_ARM_SDE_INTERFACE */
59
60
61/*
62 * This struct represents an event that has been registered. The driver
63 * maintains a list of all events, and which ones are registered. (Private
64 * events have one entry in the list, but are registered on each CPU).
65 * A pointer to this struct is passed to firmware, and back to the event
66 * handler. The event handler can then use this to invoke the registered
67 * callback, without having to walk the list.
68 *
69 * For CPU private events, this structure is per-cpu.
70 */
71struct sdei_registered_event {
72 /* For use by arch code: */
73 struct pt_regs interrupted_regs;
74
75 sdei_event_callback *callback;
76 void *callback_arg;
77 u32 event_num;
78 u8 priority;
79};
80
81/* The arch code entry point should then call this when an event arrives. */
82int notrace sdei_event_handler(struct pt_regs *regs,
83 struct sdei_registered_event *arg);
84
85/* arch code may use this to retrieve the extra registers. */
86int sdei_api_event_context(u32 query, u64 *result);
87
88#endif /* __LINUX_ARM_SDEI_H */
89