arch/arm64/include/asm/cpu_ops.h

   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 */