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 */ 40 struct 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 58 extern const struct cpu_operations *cpu_ops[NR_CPUS]; 59 int __init cpu_read_ops(int cpu); 60 61 static inline void __init cpu_read_bootcpu_ops(void) 62 { 63 cpu_read_ops(0); 64 } 65 66 #endif /* ifndef __ASM_CPU_OPS_H */ 67