linux/arch/arm64/include/asm/cpu_ops.h
Mark Rutland e8765b265a arm64: read enable-method for CPU0
With the advent of CPU_HOTPLUG, the enable-method property for CPU0 may
tells us something useful (i.e. how to hotplug it back on), so we must
read it along with all the enable-method for all the other CPUs.  Even
on UP the enable-method may tell us useful information (e.g. if a core
has some mechanism that might be usable for cpuidle), so we should
always read it.

This patch factors out the reading of the enable method, and ensures
that CPU0's enable method is read regardless of whether the kernel is
built with SMP support.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-10-25 11:33:20 +01:00

51 lines
1.8 KiB
C

/*
* Copyright (C) 2013 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_CPU_OPS_H
#define __ASM_CPU_OPS_H
#include <linux/init.h>
#include <linux/threads.h>
struct device_node;
/**
* struct cpu_operations - Callback operations for hotplugging CPUs.
*
* @name: Name of the property as appears in a devicetree cpu node's
* enable-method property.
* @cpu_init: Reads any data necessary for a specific enable-method from the
* devicetree, for a given cpu node and proposed logical id.
* @cpu_prepare: Early one-time preparation step for a cpu. If there is a
* mechanism for doing so, tests whether it is possible to boot
* the given CPU.
* @cpu_boot: Boots a cpu into the kernel.
* @cpu_postboot: Optionally, perform any post-boot cleanup or necesary
* synchronisation. Called from the cpu being booted.
*/
struct cpu_operations {
const char *name;
int (*cpu_init)(struct device_node *, unsigned int);
int (*cpu_prepare)(unsigned int);
int (*cpu_boot)(unsigned int);
void (*cpu_postboot)(void);
};
extern const struct cpu_operations *cpu_ops[NR_CPUS];
extern int __init cpu_read_ops(struct device_node *dn, int cpu);
extern void __init cpu_read_bootcpu_ops(void);
#endif /* ifndef __ASM_CPU_OPS_H */