linux/arch/arm/include/asm/bL_switcher.h
Dave Martin d08e2e0904 ARM: bL_switcher: Add query interface to discover CPU affinities
When the switcher is active, there is no straightforward way to
figure out which logical CPU a given physical CPU maps to.

This patch provides a function
bL_switcher_get_logical_index(mpidr), which is analogous to
get_logical_index().

This function returns the logical CPU on which the specified
physical CPU is grouped (or -EINVAL if unknown).
If the switcher is inactive or not present, -EUNATCH is returned instead.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
2013-09-23 18:47:31 -04:00

78 lines
2.3 KiB
C

/*
* arch/arm/include/asm/bL_switcher.h
*
* Created by: Nicolas Pitre, April 2012
* Copyright: (C) 2012-2013 Linaro Limited
*
* 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.
*/
#ifndef ASM_BL_SWITCHER_H
#define ASM_BL_SWITCHER_H
#include <linux/compiler.h>
#include <linux/types.h>
typedef void (*bL_switch_completion_handler)(void *cookie);
int bL_switch_request_cb(unsigned int cpu, unsigned int new_cluster_id,
bL_switch_completion_handler completer,
void *completer_cookie);
static inline int bL_switch_request(unsigned int cpu, unsigned int new_cluster_id)
{
return bL_switch_request_cb(cpu, new_cluster_id, NULL, NULL);
}
/*
* Register here to be notified about runtime enabling/disabling of
* the switcher.
*
* The notifier chain is called with the switcher activation lock held:
* the switcher will not be enabled or disabled during callbacks.
* Callbacks must not call bL_switcher_{get,put}_enabled().
*/
#define BL_NOTIFY_PRE_ENABLE 0
#define BL_NOTIFY_POST_ENABLE 1
#define BL_NOTIFY_PRE_DISABLE 2
#define BL_NOTIFY_POST_DISABLE 3
#ifdef CONFIG_BL_SWITCHER
int bL_switcher_register_notifier(struct notifier_block *nb);
int bL_switcher_unregister_notifier(struct notifier_block *nb);
/*
* Use these functions to temporarily prevent enabling/disabling of
* the switcher.
* bL_switcher_get_enabled() returns true if the switcher is currently
* enabled. Each call to bL_switcher_get_enabled() must be followed
* by a call to bL_switcher_put_enabled(). These functions are not
* recursive.
*/
bool bL_switcher_get_enabled(void);
void bL_switcher_put_enabled(void);
int bL_switcher_trace_trigger(void);
int bL_switcher_get_logical_index(u32 mpidr);
#else
static inline int bL_switcher_register_notifier(struct notifier_block *nb)
{
return 0;
}
static inline int bL_switcher_unregister_notifier(struct notifier_block *nb)
{
return 0;
}
static inline bool bL_switcher_get_enabled(void) { return false; }
static inline void bL_switcher_put_enabled(void) { }
static inline int bL_switcher_trace_trigger(void) { return 0; }
static inline int bL_switcher_get_logical_index(u32 mpidr) { return -EUNATCH; }
#endif /* CONFIG_BL_SWITCHER */
#endif