1/*
 2 * This program is free software; you can redistribute it and/or modify
 3 * it under the terms of the GNU General Public License version 2 as
 4 * published by the Free Software Foundation.
 5 *
 6 * This program is distributed in the hope that it will be useful,
 7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 9 * GNU General Public License for more details.
10 *
11 * Copyright (C) 2012 ARM Limited
12 *
13 * Author: Will Deacon <will.deacon@arm.com>
14 */
15
16#include <linux/init.h>
17#include <linux/smp.h>
18#include <linux/of.h>
19
20#include <asm/psci.h>
21#include <asm/smp_plat.h>
22
23/*
24 * psci_smp assumes that the following is true about PSCI:
25 *
26 * cpu_suspend   Suspend the execution on a CPU
27 * @state        we don't currently describe affinity levels, so just pass 0.
28 * @entry_point  the first instruction to be executed on return
29 * returns 0  success, < 0 on failure
30 *
31 * cpu_off       Power down a CPU
32 * @state        we don't currently describe affinity levels, so just pass 0.
33 * no return on successful call
34 *
35 * cpu_on        Power up a CPU
36 * @cpuid        cpuid of target CPU, as from MPIDR
37 * @entry_point  the first instruction to be executed on return
38 * returns 0  success, < 0 on failure
39 *
40 * migrate       Migrate the context to a different CPU
41 * @cpuid        cpuid of target CPU, as from MPIDR
42 * returns 0  success, < 0 on failure
43 *
44 */
45
46extern void secondary_startup(void);
47
48static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle)
49{
50	if (psci_ops.cpu_on)
51		return psci_ops.cpu_on(cpu_logical_map(cpu),
52				       __pa(secondary_startup));
53	return -ENODEV;
54}
55
56#ifdef CONFIG_HOTPLUG_CPU
57void __ref psci_cpu_die(unsigned int cpu)
58{
59       const struct psci_power_state ps = {
60               .type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
61       };
62
63       if (psci_ops.cpu_off)
64               psci_ops.cpu_off(ps);
65
66       /* We should never return */
67       panic("psci: cpu %d failed to shutdown\n", cpu);
68}
69#endif
70
71bool __init psci_smp_available(void)
72{
73	/* is cpu_on available at least? */
74	return (psci_ops.cpu_on != NULL);
75}
76
77struct smp_operations __initdata psci_smp_ops = {
78	.smp_boot_secondary	= psci_boot_secondary,
79#ifdef CONFIG_HOTPLUG_CPU
80	.cpu_die		= psci_cpu_die,
81#endif
82};