LXR linux/arch/arm64/include/asm/cpu

   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 necesary
  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 * @cpu_init_idle: Reads any data necessary to initialize CPU idle states for
  35 *                 a proposed logical id.
  36 * @cpu_suspend: Suspends a cpu and saves the required context. May fail owing
  37 *               to wrong parameters or error conditions. Called from the
  38 *               CPU being suspended. Must be called with IRQs disabled.
  39 */
  40struct cpu_operations {
  41        const char      *name;
  42        int             (*cpu_init)(unsigned int);
  43        int             (*cpu_prepare)(unsigned int);
  44        int             (*cpu_boot)(unsigned int);
  45        void            (*cpu_postboot)(void);
  46#ifdef CONFIG_HOTPLUG_CPU
  47        bool            (*cpu_can_disable)(unsigned int cpu);
  48        int             (*cpu_disable)(unsigned int cpu);
  49        void            (*cpu_die)(unsigned int cpu);
  50        int             (*cpu_kill)(unsigned int cpu);
  51#endif
  52#ifdef CONFIG_CPU_IDLE
  53        int             (*cpu_init_idle)(unsigned int);
  54        int             (*cpu_suspend)(unsigned long);
  55#endif
  56};
  57
  58extern const struct cpu_operations *cpu_ops[NR_CPUS];
  59int __init cpu_read_ops(int cpu);
  60
  61static inline void __init cpu_read_bootcpu_ops(void)
  62{
  63        cpu_read_ops(0);
  64}
  65
  66#endif /* ifndef __ASM_CPU_OPS_H */
  67