// SPDX-License-Identifier: GPL-2.0/* * Copyright (C) 2020 Western Digital Corporation or its affiliates. */ #include <linux/kernel.h>#include <linux/mm.h>#include <linux/sched.h>#include <linux/err.h>#include <linux/irq.h>#include <linux/cpu.h>#include <linux/sched/hotplug.h>#include <asm/irq.h>#include <asm/cpu_ops.h>#include <asm/sbi.h> void cpu_stop(void);void arch_cpu_idle_dead(void){	cpu_stop();} bool cpu_has_hotplug(unsigned int cpu){	if (cpu_ops[cpu]->cpu_stop)		return true; 	return false;} /* * __cpu_disable runs on the processor to be shutdown. */int __cpu_disable(void){	int ret = 0;	unsigned int cpu = smp_processor_id(); 	if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_stop)		return -EOPNOTSUPP; 	if (cpu_ops[cpu]->cpu_disable)		ret = cpu_ops[cpu]->cpu_disable(cpu); 	if (ret)		return ret; 	remove_cpu_topology(cpu);	set_cpu_online(cpu, false);	irq_migrate_all_off_this_cpu(); 	return ret;} /* * Called on the thread which is asking for a CPU to be shutdown. */void __cpu_die(unsigned int cpu){	int ret = 0; 	if (!cpu_wait_death(cpu, 5)) {		pr_err("CPU %u: didn't die\n", cpu);		return;	}	pr_notice("CPU%u: off\n", cpu); 	/* Verify from the firmware if the cpu is really stopped*/	if (cpu_ops[cpu]->cpu_is_stopped)		ret = cpu_ops[cpu]->cpu_is_stopped(cpu);	if (ret)		pr_warn("CPU%d may not have stopped: %d\n", cpu, ret);} /* * Called from the idle thread for the CPU which has been shutdown. */void cpu_stop(void){	idle_task_exit(); 	(void)cpu_report_death(); 	cpu_ops[smp_processor_id()]->cpu_stop();	/* It should never reach here */	BUG();}