xref: /linux/arch/arm64/include/asm/cpu_ops.h (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * Copyright (C) 2013 ARM Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
15  */
16 #ifndef __ASM_CPU_OPS_H
17 #define __ASM_CPU_OPS_H
18 
19 #include <linux/init.h>
20 #include <linux/threads.h>
21 
22 struct device_node;
23 
24 /**
25  * struct cpu_operations - Callback operations for hotplugging CPUs.
26  *
27  * @name:	Name of the property as appears in a devicetree cpu node's
28  *		enable-method property.
29  * @cpu_init:	Reads any data necessary for a specific enable-method from the
30  *		devicetree, for a given cpu node and proposed logical id.
31  * @cpu_prepare: Early one-time preparation step for a cpu. If there is a
32  *		mechanism for doing so, tests whether it is possible to boot
33  *		the given CPU.
34  * @cpu_boot:	Boots a cpu into the kernel.
35  * @cpu_postboot: Optionally, perform any post-boot cleanup or necesary
36  *		synchronisation. Called from the cpu being booted.
37  * @cpu_disable: Prepares a cpu to die. May fail for some mechanism-specific
38  * 		reason, which will cause the hot unplug to be aborted. Called
39  * 		from the cpu to be killed.
40  * @cpu_die:	Makes a cpu leave the kernel. Must not fail. Called from the
41  *		cpu being killed.
42  * @cpu_kill:  Ensures a cpu has left the kernel. Called from another cpu.
43  * @cpu_suspend: Suspends a cpu and saves the required context. May fail owing
44  *               to wrong parameters or error conditions. Called from the
45  *               CPU being suspended. Must be called with IRQs disabled.
46  */
47 struct cpu_operations {
48 	const char	*name;
49 	int		(*cpu_init)(struct device_node *, unsigned int);
50 	int		(*cpu_prepare)(unsigned int);
51 	int		(*cpu_boot)(unsigned int);
52 	void		(*cpu_postboot)(void);
53 #ifdef CONFIG_HOTPLUG_CPU
54 	int		(*cpu_disable)(unsigned int cpu);
55 	void		(*cpu_die)(unsigned int cpu);
56 	int		(*cpu_kill)(unsigned int cpu);
57 #endif
58 #ifdef CONFIG_ARM64_CPU_SUSPEND
59 	int		(*cpu_suspend)(unsigned long);
60 #endif
61 };
62 
63 extern const struct cpu_operations *cpu_ops[NR_CPUS];
64 extern int __init cpu_read_ops(struct device_node *dn, int cpu);
65 extern void __init cpu_read_bootcpu_ops(void);
66 
67 #endif /* ifndef __ASM_CPU_OPS_H */
68