Loading...
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) 2013 ARM Limited
12 *
13 * Author: Will Deacon <will.deacon@arm.com>
14 */
15
16#define pr_fmt(fmt) "psci: " fmt
17
18#include <linux/init.h>
19#include <linux/of.h>
20#include <linux/smp.h>
21#include <linux/delay.h>
22#include <linux/psci.h>
23#include <linux/mm.h>
24
25#include <uapi/linux/psci.h>
26
27#include <asm/compiler.h>
28#include <asm/cpu_ops.h>
29#include <asm/errno.h>
30#include <asm/smp_plat.h>
31
32static int __init cpu_psci_cpu_init(unsigned int cpu)
33{
34 return 0;
35}
36
37static int __init cpu_psci_cpu_prepare(unsigned int cpu)
38{
39 if (!psci_ops.cpu_on) {
40 pr_err("no cpu_on method, not booting CPU%d\n", cpu);
41 return -ENODEV;
42 }
43
44 return 0;
45}
46
47static int cpu_psci_cpu_boot(unsigned int cpu)
48{
49 int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa_symbol(secondary_entry));
50 if (err)
51 pr_err("failed to boot CPU%d (%d)\n", cpu, err);
52
53 return err;
54}
55
56#ifdef CONFIG_HOTPLUG_CPU
57static int cpu_psci_cpu_disable(unsigned int cpu)
58{
59 /* Fail early if we don't have CPU_OFF support */
60 if (!psci_ops.cpu_off)
61 return -EOPNOTSUPP;
62
63 /* Trusted OS will deny CPU_OFF */
64 if (psci_tos_resident_on(cpu))
65 return -EPERM;
66
67 return 0;
68}
69
70static void cpu_psci_cpu_die(unsigned int cpu)
71{
72 int ret;
73 /*
74 * There are no known implementations of PSCI actually using the
75 * power state field, pass a sensible default for now.
76 */
77 u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
78 PSCI_0_2_POWER_STATE_TYPE_SHIFT;
79
80 ret = psci_ops.cpu_off(state);
81
82 pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
83}
84
85static int cpu_psci_cpu_kill(unsigned int cpu)
86{
87 int err, i;
88
89 if (!psci_ops.affinity_info)
90 return 0;
91 /*
92 * cpu_kill could race with cpu_die and we can
93 * potentially end up declaring this cpu undead
94 * while it is dying. So, try again a few times.
95 */
96
97 for (i = 0; i < 10; i++) {
98 err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
99 if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
100 pr_info("CPU%d killed.\n", cpu);
101 return 0;
102 }
103
104 msleep(10);
105 pr_info("Retrying again to check for CPU kill\n");
106 }
107
108 pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
109 cpu, err);
110 return -ETIMEDOUT;
111}
112#endif
113
114const struct cpu_operations cpu_psci_ops = {
115 .name = "psci",
116#ifdef CONFIG_CPU_IDLE
117 .cpu_init_idle = psci_cpu_init_idle,
118 .cpu_suspend = psci_cpu_suspend_enter,
119#endif
120 .cpu_init = cpu_psci_cpu_init,
121 .cpu_prepare = cpu_psci_cpu_prepare,
122 .cpu_boot = cpu_psci_cpu_boot,
123#ifdef CONFIG_HOTPLUG_CPU
124 .cpu_disable = cpu_psci_cpu_disable,
125 .cpu_die = cpu_psci_cpu_die,
126 .cpu_kill = cpu_psci_cpu_kill,
127#endif
128};
129
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) 2013 ARM Limited
12 *
13 * Author: Will Deacon <will.deacon@arm.com>
14 */
15
16#define pr_fmt(fmt) "psci: " fmt
17
18#include <linux/init.h>
19#include <linux/of.h>
20#include <linux/smp.h>
21#include <linux/delay.h>
22#include <linux/psci.h>
23
24#include <uapi/linux/psci.h>
25
26#include <asm/compiler.h>
27#include <asm/cpu_ops.h>
28#include <asm/errno.h>
29#include <asm/smp_plat.h>
30
31static int __init cpu_psci_cpu_init(unsigned int cpu)
32{
33 return 0;
34}
35
36static int __init cpu_psci_cpu_prepare(unsigned int cpu)
37{
38 if (!psci_ops.cpu_on) {
39 pr_err("no cpu_on method, not booting CPU%d\n", cpu);
40 return -ENODEV;
41 }
42
43 return 0;
44}
45
46static int cpu_psci_cpu_boot(unsigned int cpu)
47{
48 int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry));
49 if (err)
50 pr_err("failed to boot CPU%d (%d)\n", cpu, err);
51
52 return err;
53}
54
55#ifdef CONFIG_HOTPLUG_CPU
56static int cpu_psci_cpu_disable(unsigned int cpu)
57{
58 /* Fail early if we don't have CPU_OFF support */
59 if (!psci_ops.cpu_off)
60 return -EOPNOTSUPP;
61
62 /* Trusted OS will deny CPU_OFF */
63 if (psci_tos_resident_on(cpu))
64 return -EPERM;
65
66 return 0;
67}
68
69static void cpu_psci_cpu_die(unsigned int cpu)
70{
71 int ret;
72 /*
73 * There are no known implementations of PSCI actually using the
74 * power state field, pass a sensible default for now.
75 */
76 u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
77 PSCI_0_2_POWER_STATE_TYPE_SHIFT;
78
79 ret = psci_ops.cpu_off(state);
80
81 pr_crit("unable to power off CPU%u (%d)\n", cpu, ret);
82}
83
84static int cpu_psci_cpu_kill(unsigned int cpu)
85{
86 int err, i;
87
88 if (!psci_ops.affinity_info)
89 return 0;
90 /*
91 * cpu_kill could race with cpu_die and we can
92 * potentially end up declaring this cpu undead
93 * while it is dying. So, try again a few times.
94 */
95
96 for (i = 0; i < 10; i++) {
97 err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
98 if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
99 pr_info("CPU%d killed.\n", cpu);
100 return 0;
101 }
102
103 msleep(10);
104 pr_info("Retrying again to check for CPU kill\n");
105 }
106
107 pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
108 cpu, err);
109 return -ETIMEDOUT;
110}
111#endif
112
113const struct cpu_operations cpu_psci_ops = {
114 .name = "psci",
115#ifdef CONFIG_CPU_IDLE
116 .cpu_init_idle = psci_cpu_init_idle,
117 .cpu_suspend = psci_cpu_suspend_enter,
118#endif
119 .cpu_init = cpu_psci_cpu_init,
120 .cpu_prepare = cpu_psci_cpu_prepare,
121 .cpu_boot = cpu_psci_cpu_boot,
122#ifdef CONFIG_HOTPLUG_CPU
123 .cpu_disable = cpu_psci_cpu_disable,
124 .cpu_die = cpu_psci_cpu_die,
125 .cpu_kill = cpu_psci_cpu_kill,
126#endif
127};
128