Commit | Line | Data |
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cd1aebf5 MR |
1 | /* |
2 | * CPU kernel entry/exit control | |
3 | * | |
4 | * Copyright (C) 2013 ARM Ltd. | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program. If not, see <http://www.gnu.org/licenses/>. | |
17 | */ | |
18 | ||
0f078336 | 19 | #include <linux/acpi.h> |
5a9e3e15 | 20 | #include <linux/cache.h> |
e8765b26 MR |
21 | #include <linux/errno.h> |
22 | #include <linux/of.h> | |
cd1aebf5 | 23 | #include <linux/string.h> |
0f078336 LP |
24 | #include <asm/acpi.h> |
25 | #include <asm/cpu_ops.h> | |
26 | #include <asm/smp_plat.h> | |
cd1aebf5 MR |
27 | |
28 | extern const struct cpu_operations smp_spin_table_ops; | |
5e89c55e | 29 | extern const struct cpu_operations acpi_parking_protocol_ops; |
cd1aebf5 MR |
30 | extern const struct cpu_operations cpu_psci_ops; |
31 | ||
5a9e3e15 | 32 | const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; |
cd1aebf5 | 33 | |
5e89c55e | 34 | static const struct cpu_operations *dt_supported_cpu_ops[] __initconst = { |
cd1aebf5 | 35 | &smp_spin_table_ops, |
756854d9 | 36 | &cpu_psci_ops, |
cd1aebf5 MR |
37 | NULL, |
38 | }; | |
39 | ||
5e89c55e LP |
40 | static const struct cpu_operations *acpi_supported_cpu_ops[] __initconst = { |
41 | #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL | |
42 | &acpi_parking_protocol_ops, | |
43 | #endif | |
44 | &cpu_psci_ops, | |
45 | NULL, | |
46 | }; | |
47 | ||
0f078336 | 48 | static const struct cpu_operations * __init cpu_get_ops(const char *name) |
cd1aebf5 | 49 | { |
5e89c55e LP |
50 | const struct cpu_operations **ops; |
51 | ||
52 | ops = acpi_disabled ? dt_supported_cpu_ops : acpi_supported_cpu_ops; | |
cd1aebf5 MR |
53 | |
54 | while (*ops) { | |
55 | if (!strcmp(name, (*ops)->name)) | |
56 | return *ops; | |
57 | ||
58 | ops++; | |
59 | } | |
60 | ||
61 | return NULL; | |
62 | } | |
e8765b26 | 63 | |
0f078336 LP |
64 | static const char *__init cpu_read_enable_method(int cpu) |
65 | { | |
66 | const char *enable_method; | |
67 | ||
68 | if (acpi_disabled) { | |
69 | struct device_node *dn = of_get_cpu_node(cpu, NULL); | |
70 | ||
71 | if (!dn) { | |
72 | if (!cpu) | |
73 | pr_err("Failed to find device node for boot cpu\n"); | |
74 | return NULL; | |
75 | } | |
76 | ||
77 | enable_method = of_get_property(dn, "enable-method", NULL); | |
78 | if (!enable_method) { | |
79 | /* | |
80 | * The boot CPU may not have an enable method (e.g. | |
81 | * when spin-table is used for secondaries). | |
82 | * Don't warn spuriously. | |
83 | */ | |
84 | if (cpu != 0) | |
85 | pr_err("%s: missing enable-method property\n", | |
86 | dn->full_name); | |
87 | } | |
88 | } else { | |
89 | enable_method = acpi_get_enable_method(cpu); | |
5e89c55e LP |
90 | if (!enable_method) { |
91 | /* | |
92 | * In ACPI systems the boot CPU does not require | |
93 | * checking the enable method since for some | |
94 | * boot protocol (ie parking protocol) it need not | |
95 | * be initialized. Don't warn spuriously. | |
96 | */ | |
97 | if (cpu != 0) | |
98 | pr_err("Unsupported ACPI enable-method\n"); | |
99 | } | |
0f078336 LP |
100 | } |
101 | ||
102 | return enable_method; | |
103 | } | |
e8765b26 | 104 | /* |
0f078336 | 105 | * Read a cpu's enable method and record it in cpu_ops. |
e8765b26 | 106 | */ |
819a8826 | 107 | int __init cpu_read_ops(int cpu) |
e8765b26 | 108 | { |
0f078336 | 109 | const char *enable_method = cpu_read_enable_method(cpu); |
819a8826 | 110 | |
0f078336 | 111 | if (!enable_method) |
819a8826 | 112 | return -ENODEV; |
e8765b26 MR |
113 | |
114 | cpu_ops[cpu] = cpu_get_ops(enable_method); | |
115 | if (!cpu_ops[cpu]) { | |
0f078336 | 116 | pr_warn("Unsupported enable-method: %s\n", enable_method); |
e8765b26 MR |
117 | return -EOPNOTSUPP; |
118 | } | |
119 | ||
120 | return 0; | |
121 | } |