2 * CPU kernel entry/exit control
4 * Copyright (C) 2013 ARM Ltd.
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.
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.
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/>.
19 #include <linux/acpi.h>
20 #include <linux/errno.h>
22 #include <linux/string.h>
24 #include <asm/cpu_ops.h>
25 #include <asm/smp_plat.h>
27 extern const struct cpu_operations smp_spin_table_ops;
28 extern const struct cpu_operations acpi_parking_protocol_ops;
29 extern const struct cpu_operations cpu_psci_ops;
31 const struct cpu_operations *cpu_ops[NR_CPUS];
33 static const struct cpu_operations *dt_supported_cpu_ops[] __initconst = {
39 static const struct cpu_operations *acpi_supported_cpu_ops[] __initconst = {
40 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
41 &acpi_parking_protocol_ops,
47 static const struct cpu_operations * __init cpu_get_ops(const char *name)
49 const struct cpu_operations **ops;
51 ops = acpi_disabled ? dt_supported_cpu_ops : acpi_supported_cpu_ops;
54 if (!strcmp(name, (*ops)->name))
63 static const char *__init cpu_read_enable_method(int cpu)
65 const char *enable_method;
68 struct device_node *dn = of_get_cpu_node(cpu, NULL);
72 pr_err("Failed to find device node for boot cpu\n");
76 enable_method = of_get_property(dn, "enable-method", NULL);
79 * The boot CPU may not have an enable method (e.g.
80 * when spin-table is used for secondaries).
81 * Don't warn spuriously.
84 pr_err("%s: missing enable-method property\n",
88 enable_method = acpi_get_enable_method(cpu);
91 * In ACPI systems the boot CPU does not require
92 * checking the enable method since for some
93 * boot protocol (ie parking protocol) it need not
94 * be initialized. Don't warn spuriously.
97 pr_err("Unsupported ACPI enable-method\n");
101 return enable_method;
104 * Read a cpu's enable method and record it in cpu_ops.
106 int __init cpu_read_ops(int cpu)
108 const char *enable_method = cpu_read_enable_method(cpu);
113 cpu_ops[cpu] = cpu_get_ops(enable_method);
115 pr_warn("Unsupported enable-method: %s\n", enable_method);