1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_REBOOT_H
3#define _LINUX_REBOOT_H
4
5
6#include <linux/notifier.h>
7#include <uapi/linux/reboot.h>
8
9struct device;
10struct sys_off_handler;
11
12#define SYS_DOWN 0x0001 /* Notify of system down */
13#define SYS_RESTART SYS_DOWN
14#define SYS_HALT 0x0002 /* Notify of system halt */
15#define SYS_POWER_OFF 0x0003 /* Notify of system power off */
16
17enum reboot_mode {
18 REBOOT_UNDEFINED = -1,
19 REBOOT_COLD = 0,
20 REBOOT_WARM,
21 REBOOT_HARD,
22 REBOOT_SOFT,
23 REBOOT_GPIO,
24};
25extern enum reboot_mode reboot_mode;
26extern enum reboot_mode panic_reboot_mode;
27
28enum reboot_type {
29 BOOT_TRIPLE = 't',
30 BOOT_KBD = 'k',
31 BOOT_BIOS = 'b',
32 BOOT_ACPI = 'a',
33 BOOT_EFI = 'e',
34 BOOT_CF9_FORCE = 'p',
35 BOOT_CF9_SAFE = 'q',
36};
37extern enum reboot_type reboot_type;
38
39extern int reboot_default;
40extern int reboot_cpu;
41extern int reboot_force;
42
43
44extern int register_reboot_notifier(struct notifier_block *);
45extern int unregister_reboot_notifier(struct notifier_block *);
46
47extern int devm_register_reboot_notifier(struct device *, struct notifier_block *);
48
49extern int register_restart_handler(struct notifier_block *);
50extern int unregister_restart_handler(struct notifier_block *);
51extern void do_kernel_restart(char *cmd);
52
53/*
54 * Architecture-specific implementations of sys_reboot commands.
55 */
56
57extern void migrate_to_reboot_cpu(void);
58extern void machine_restart(char *cmd);
59extern void machine_halt(void);
60extern void machine_power_off(void);
61
62extern void machine_shutdown(void);
63struct pt_regs;
64extern void machine_crash_shutdown(struct pt_regs *);
65
66void do_kernel_power_off(void);
67
68/*
69 * sys-off handler API.
70 */
71
72/*
73 * Standard sys-off priority levels. Users are expected to set priorities
74 * relative to the standard levels.
75 *
76 * SYS_OFF_PRIO_PLATFORM: Use this for platform-level handlers.
77 *
78 * SYS_OFF_PRIO_LOW: Use this for handler of last resort.
79 *
80 * SYS_OFF_PRIO_DEFAULT: Use this for normal handlers.
81 *
82 * SYS_OFF_PRIO_HIGH: Use this for higher priority handlers.
83 *
84 * SYS_OFF_PRIO_FIRMWARE: Use this if handler uses firmware call.
85 */
86#define SYS_OFF_PRIO_PLATFORM -256
87#define SYS_OFF_PRIO_LOW -128
88#define SYS_OFF_PRIO_DEFAULT 0
89#define SYS_OFF_PRIO_HIGH 192
90#define SYS_OFF_PRIO_FIRMWARE 224
91
92enum sys_off_mode {
93 /**
94 * @SYS_OFF_MODE_POWER_OFF_PREPARE:
95 *
96 * Handlers prepare system to be powered off. Handlers are
97 * allowed to sleep.
98 */
99 SYS_OFF_MODE_POWER_OFF_PREPARE,
100
101 /**
102 * @SYS_OFF_MODE_POWER_OFF:
103 *
104 * Handlers power-off system. Handlers are disallowed to sleep.
105 */
106 SYS_OFF_MODE_POWER_OFF,
107
108 /**
109 * @SYS_OFF_MODE_RESTART_PREPARE:
110 *
111 * Handlers prepare system to be restarted. Handlers are
112 * allowed to sleep.
113 */
114 SYS_OFF_MODE_RESTART_PREPARE,
115
116 /**
117 * @SYS_OFF_MODE_RESTART:
118 *
119 * Handlers restart system. Handlers are disallowed to sleep.
120 */
121 SYS_OFF_MODE_RESTART,
122};
123
124/**
125 * struct sys_off_data - sys-off callback argument
126 *
127 * @mode: Mode ID. Currently used only by the sys-off restart mode,
128 * see enum reboot_mode for the available modes.
129 * @cb_data: User's callback data.
130 * @cmd: Command string. Currently used only by the sys-off restart mode,
131 * NULL otherwise.
132 * @dev: Device of the sys-off handler. Only if known (devm_register_*),
133 * NULL otherwise.
134 */
135struct sys_off_data {
136 int mode;
137 void *cb_data;
138 const char *cmd;
139 struct device *dev;
140};
141
142struct sys_off_handler *
143register_sys_off_handler(enum sys_off_mode mode,
144 int priority,
145 int (*callback)(struct sys_off_data *data),
146 void *cb_data);
147void unregister_sys_off_handler(struct sys_off_handler *handler);
148
149int devm_register_sys_off_handler(struct device *dev,
150 enum sys_off_mode mode,
151 int priority,
152 int (*callback)(struct sys_off_data *data),
153 void *cb_data);
154
155int devm_register_power_off_handler(struct device *dev,
156 int (*callback)(struct sys_off_data *data),
157 void *cb_data);
158
159int devm_register_restart_handler(struct device *dev,
160 int (*callback)(struct sys_off_data *data),
161 void *cb_data);
162
163int register_platform_power_off(void (*power_off)(void));
164void unregister_platform_power_off(void (*power_off)(void));
165
166/*
167 * Architecture independent implemenations of sys_reboot commands.
168 */
169
170extern void kernel_restart_prepare(char *cmd);
171extern void kernel_restart(char *cmd);
172extern void kernel_halt(void);
173extern void kernel_power_off(void);
174extern bool kernel_can_power_off(void);
175
176void ctrl_alt_del(void);
177
178extern void orderly_poweroff(bool force);
179extern void orderly_reboot(void);
180
181/**
182 * enum hw_protection_action - Hardware protection action
183 *
184 * @HWPROT_ACT_DEFAULT:
185 * The default action should be taken. This is HWPROT_ACT_SHUTDOWN
186 * by default, but can be overridden.
187 * @HWPROT_ACT_SHUTDOWN:
188 * The system should be shut down (powered off) for HW protection.
189 * @HWPROT_ACT_REBOOT:
190 * The system should be rebooted for HW protection.
191 */
192enum hw_protection_action { HWPROT_ACT_DEFAULT, HWPROT_ACT_SHUTDOWN, HWPROT_ACT_REBOOT };
193
194void __hw_protection_trigger(const char *reason, int ms_until_forced,
195 enum hw_protection_action action);
196
197/**
198 * hw_protection_trigger - Trigger default emergency system hardware protection action
199 *
200 * @reason: Reason of emergency shutdown or reboot to be printed.
201 * @ms_until_forced: Time to wait for orderly shutdown or reboot before
202 * triggering it. Negative value disables the forced
203 * shutdown or reboot.
204 *
205 * Initiate an emergency system shutdown or reboot in order to protect
206 * hardware from further damage. The exact action taken is controllable at
207 * runtime and defaults to shutdown.
208 */
209static inline void hw_protection_trigger(const char *reason, int ms_until_forced)
210{
211 __hw_protection_trigger(reason, ms_until_forced, action: HWPROT_ACT_DEFAULT);
212}
213
214/*
215 * Emergency restart, callable from an interrupt handler.
216 */
217
218extern void emergency_restart(void);
219#include <asm/emergency-restart.h>
220
221#endif /* _LINUX_REBOOT_H */
222