1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (c) 2020 Western Digital Corporation or its affiliates. 4 * Based on arch/arm64/include/asm/cpu_ops.h 5 */ 6 #ifndef __ASM_CPU_OPS_H 7 #define __ASM_CPU_OPS_H 8 9 #include <linux/init.h> 10 #include <linux/sched.h> 11 #include <linux/threads.h> 12 13 /** 14 * struct cpu_operations - Callback operations for hotplugging CPUs. 15 * 16 * @name: Name of the boot protocol. 17 * @cpu_prepare: Early one-time preparation step for a cpu. If there 18 * is a mechanism for doing so, tests whether it is 19 * possible to boot the given HART. 20 * @cpu_start: Boots a cpu into the kernel. 21 * @cpu_disable: Prepares a cpu to die. May fail for some 22 * mechanism-specific reason, which will cause the hot 23 * unplug to be aborted. Called from the cpu to be killed. 24 * @cpu_stop: Makes a cpu leave the kernel. Must not fail. Called from 25 * the cpu being stopped. 26 * @cpu_is_stopped: Ensures a cpu has left the kernel. Called from another 27 * cpu. 28 */ 29 struct cpu_operations { 30 const char *name; 31 int (*cpu_prepare)(unsigned int cpu); 32 int (*cpu_start)(unsigned int cpu, 33 struct task_struct *tidle); 34 #ifdef CONFIG_HOTPLUG_CPU 35 int (*cpu_disable)(unsigned int cpu); 36 void (*cpu_stop)(void); 37 int (*cpu_is_stopped)(unsigned int cpu); 38 #endif 39 }; 40 41 extern const struct cpu_operations cpu_ops_spinwait; 42 extern const struct cpu_operations *cpu_ops[NR_CPUS]; 43 void __init cpu_set_ops(int cpu); 44 45 #endif /* ifndef __ASM_CPU_OPS_H */ 46