blob: df84e0c13db188c13e28eb11f2eaa79d539a5d01 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
// 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();
}
|