/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (c) 2020 Western Digital Corporation or its affiliates.
 * Based on arch/arm64/include/asm/cpu_ops.h
 */
#ifndef __ASM_CPU_OPS_H
#define __ASM_CPU_OPS_H

#include <linux/init.h>
#include <linux/sched.h>
#include <linux/threads.h>

/**
 * struct cpu_operations - Callback operations for hotplugging CPUs.
 *
 * @name:        Name of the boot protocol.
 * @cpu_prepare:    Early one-time preparation step for a cpu. If there
 *            is a mechanism for doing so, tests whether it is
 *            possible to boot the given HART.
 * @cpu_start:        Boots a cpu into the kernel.
 * @cpu_disable:    Prepares a cpu to die. May fail for some
 *            mechanism-specific reason, which will cause the hot
 *            unplug to be aborted. Called from the cpu to be killed.
 * @cpu_stop:        Makes a cpu leave the kernel. Must not fail. Called from
 *            the cpu being stopped.
 * @cpu_is_stopped:    Ensures a cpu has left the kernel. Called from another
 *            cpu.
 */
struct cpu_operations {
    const char    *name;
    int        (*cpu_prepare)(unsigned int cpu);
    int        (*cpu_start)(unsigned int cpu,
                     struct task_struct *tidle);
#ifdef CONFIG_HOTPLUG_CPU
    int        (*cpu_disable)(unsigned int cpu);
    void        (*cpu_stop)(void);
    int        (*cpu_is_stopped)(unsigned int cpu);
#endif
};

extern const struct cpu_operations cpu_ops_spinwait;
extern const struct cpu_operations *cpu_ops[NR_CPUS];
void __init cpu_set_ops(int cpu);

#endif /* ifndef __ASM_CPU_OPS_H */