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1 /*
2 * ARM64 CPU idle arch support
3 *
4 * Copyright (C) 2014 ARM Ltd.
5 * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 #include <linux/acpi.h>
13 #include <linux/cpuidle.h>
14 #include <linux/cpu_pm.h>
15 #include <linux/of.h>
16 #include <linux/of_device.h>
17
18 #include <asm/cpuidle.h>
19 #include <asm/cpu_ops.h>
20
21 int arm_cpuidle_init(unsigned int cpu)
22 {
23 int ret = -EOPNOTSUPP;
24
25 if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_suspend &&
26 cpu_ops[cpu]->cpu_init_idle)
27 ret = cpu_ops[cpu]->cpu_init_idle(cpu);
28
29 return ret;
30 }
31
32 /**
33 * cpu_suspend() - function to enter a low-power idle state
34 * @arg: argument to pass to CPU suspend operations
35 *
36 * Return: 0 on success, -EOPNOTSUPP if CPU suspend hook not initialized, CPU
37 * operations back-end error code otherwise.
38 */
39 int arm_cpuidle_suspend(int index)
40 {
41 int cpu = smp_processor_id();
42
43 return cpu_ops[cpu]->cpu_suspend(index);
44 }
45
46 #ifdef CONFIG_ACPI
47
48 #include <acpi/processor.h>
49
50 int acpi_processor_ffh_lpi_probe(unsigned int cpu)
51 {
52 return arm_cpuidle_init(cpu);
53 }
54
55 int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi)
56 {
57 return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index);
58 }
59 #endif