1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2013 ARM Ltd.
4 */
5#ifndef __ASM_CPU_OPS_H
6#define __ASM_CPU_OPS_H
7
8#include <linux/init.h>
9#include <linux/threads.h>
10
11/**
12 * struct cpu_operations - Callback operations for hotplugging CPUs.
13 *
14 * @name:	Name of the property as appears in a devicetree cpu node's
15 *		enable-method property. On systems booting with ACPI, @name
16 *		identifies the struct cpu_operations entry corresponding to
17 *		the boot protocol specified in the ACPI MADT table.
18 * @cpu_init:	Reads any data necessary for a specific enable-method for a
19 *		proposed logical id.
20 * @cpu_prepare: Early one-time preparation step for a cpu. If there is a
21 *		mechanism for doing so, tests whether it is possible to boot
22 *		the given CPU.
23 * @cpu_boot:	Boots a cpu into the kernel.
24 * @cpu_postboot: Optionally, perform any post-boot cleanup or necessary
25 *		synchronisation. Called from the cpu being booted.
26 * @cpu_can_disable: Determines whether a CPU can be disabled based on
27 *		mechanism-specific information.
28 * @cpu_disable: Prepares a cpu to die. May fail for some mechanism-specific
29 * 		reason, which will cause the hot unplug to be aborted. Called
30 * 		from the cpu to be killed.
31 * @cpu_die:	Makes a cpu leave the kernel. Must not fail. Called from the
32 *		cpu being killed.
33 * @cpu_kill:  Ensures a cpu has left the kernel. Called from another cpu.
34 */
35struct cpu_operations {
36	const char	*name;
37	int		(*cpu_init)(unsigned int);
38	int		(*cpu_prepare)(unsigned int);
39	int		(*cpu_boot)(unsigned int);
40	void		(*cpu_postboot)(void);
41#ifdef CONFIG_HOTPLUG_CPU
42	bool		(*cpu_can_disable)(unsigned int cpu);
43	int		(*cpu_disable)(unsigned int cpu);
44	void		(*cpu_die)(unsigned int cpu);
45	int		(*cpu_kill)(unsigned int cpu);
46#endif
47};
48
49int __init init_cpu_ops(int cpu);
50extern const struct cpu_operations *get_cpu_ops(int cpu);
51
52static inline void __init init_bootcpu_ops(void)
53{
54	init_cpu_ops(0);
55}
56
57#endif /* ifndef __ASM_CPU_OPS_H */
58