cregit-Linux how code gets into the kernel

Release 4.7 include/linux/hwspinlock.h

Directory: include/linux
/*
 * Hardware spinlock public header
 *
 * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com
 *
 * Contact: Ohad Ben-Cohen <ohad@wizery.com>
 *
 * 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.
 */

#ifndef __LINUX_HWSPINLOCK_H

#define __LINUX_HWSPINLOCK_H

#include <linux/err.h>
#include <linux/sched.h>

/* hwspinlock mode argument */

#define HWLOCK_IRQSTATE	0x01	
/* Disable interrupts, save state */

#define HWLOCK_IRQ	0x02	
/* Disable interrupts, don't save state */

struct device;
struct device_node;
struct hwspinlock;
struct hwspinlock_device;
struct hwspinlock_ops;

/**
 * struct hwspinlock_pdata - platform data for hwspinlock drivers
 * @base_id: base id for this hwspinlock device
 *
 * hwspinlock devices provide system-wide hardware locks that are used
 * by remote processors that have no other way to achieve synchronization.
 *
 * To achieve that, each physical lock must have a system-wide id number
 * that is agreed upon, otherwise remote processors can't possibly assume
 * they're using the same hardware lock.
 *
 * Usually boards have a single hwspinlock device, which provides several
 * hwspinlocks, and in this case, they can be trivially numbered 0 to
 * (num-of-locks - 1).
 *
 * In case boards have several hwspinlocks devices, a different base id
 * should be used for each hwspinlock device (they can't all use 0 as
 * a starting id!).
 *
 * This platform data structure should be used to provide the base id
 * for each device (which is trivially 0 when only a single hwspinlock
 * device exists). It can be shared between different platforms, hence
 * its location.
 */

struct hwspinlock_pdata {
	
int base_id;
};

#if defined(CONFIG_HWSPINLOCK) || defined(CONFIG_HWSPINLOCK_MODULE)

int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev,
		const struct hwspinlock_ops *ops, int base_id, int num_locks);
int hwspin_lock_unregister(struct hwspinlock_device *bank);
struct hwspinlock *hwspin_lock_request(void);
struct hwspinlock *hwspin_lock_request_specific(unsigned int id);
int hwspin_lock_free(struct hwspinlock *hwlock);
int of_hwspin_lock_get_id(struct device_node *np, int index);
int hwspin_lock_get_id(struct hwspinlock *hwlock);
int __hwspin_lock_timeout(struct hwspinlock *, unsigned int, int,
							unsigned long *);
int __hwspin_trylock(struct hwspinlock *, int, unsigned long *);
void __hwspin_unlock(struct hwspinlock *, int, unsigned long *);

#else /* !CONFIG_HWSPINLOCK */

/*
 * We don't want these functions to fail if CONFIG_HWSPINLOCK is not
 * enabled. We prefer to silently succeed in this case, and let the
 * code path get compiled away. This way, if CONFIG_HWSPINLOCK is not
 * required on a given setup, users will still work.
 *
 * The only exception is hwspin_lock_register/hwspin_lock_unregister, with which
 * we _do_ want users to fail (no point in registering hwspinlock instances if
 * the framework is not available).
 *
 * Note: ERR_PTR(-ENODEV) will still be considered a success for NULL-checking
 * users. Others, which care, can still check this with IS_ERR.
 */

static inline struct hwspinlock *hwspin_lock_request(void) { return ERR_PTR(-ENODEV); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen18100.00%1100.00%
Total18100.00%1100.00%


static inline struct hwspinlock *hwspin_lock_request_specific(unsigned int id) { return ERR_PTR(-ENODEV); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen20100.00%1100.00%
Total20100.00%1100.00%


static inline int hwspin_lock_free(struct hwspinlock *hwlock) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen15100.00%1100.00%
Total15100.00%1100.00%


static inline int __hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int to, int mode, unsigned long *flags) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen27100.00%1100.00%
Total27100.00%1100.00%


static inline int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen23100.00%1100.00%
Total23100.00%1100.00%


static inline void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags) { }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen1894.74%150.00%
axel linaxel lin15.26%150.00%
Total19100.00%2100.00%


static inline int of_hwspin_lock_get_id(struct device_node *np, int index) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
suman annasuman anna18100.00%1100.00%
Total18100.00%1100.00%


static inline int hwspin_lock_get_id(struct hwspinlock *hwlock) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen15100.00%1100.00%
Total15100.00%1100.00%

#endif /* !CONFIG_HWSPINLOCK */ /** * hwspin_trylock_irqsave() - try to lock an hwspinlock, disable interrupts * @hwlock: an hwspinlock which we want to trylock * @flags: a pointer to where the caller's interrupt state will be saved at * * This function attempts to lock the underlying hwspinlock, and will * immediately fail if the hwspinlock is already locked. * * Upon a successful return from this function, preemption and local * interrupts are disabled (previous interrupts state is saved at @flags), * so the caller must not sleep, and is advised to release the hwspinlock * as soon as possible. * * Returns 0 if we successfully locked the hwspinlock, -EBUSY if * the hwspinlock was already taken, and -EINVAL if @hwlock is invalid. */
static inline int hwspin_trylock_irqsave(struct hwspinlock *hwlock, unsigned long *flags) { return __hwspin_trylock(hwlock, HWLOCK_IRQSTATE, flags); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen27100.00%1100.00%
Total27100.00%1100.00%

/** * hwspin_trylock_irq() - try to lock an hwspinlock, disable interrupts * @hwlock: an hwspinlock which we want to trylock * * This function attempts to lock the underlying hwspinlock, and will * immediately fail if the hwspinlock is already locked. * * Upon a successful return from this function, preemption and local * interrupts are disabled, so the caller must not sleep, and is advised * to release the hwspinlock as soon as possible. * * Returns 0 if we successfully locked the hwspinlock, -EBUSY if * the hwspinlock was already taken, and -EINVAL if @hwlock is invalid. */
static inline int hwspin_trylock_irq(struct hwspinlock *hwlock) { return __hwspin_trylock(hwlock, HWLOCK_IRQ, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen22100.00%1100.00%
Total22100.00%1100.00%

/** * hwspin_trylock() - attempt to lock a specific hwspinlock * @hwlock: an hwspinlock which we want to trylock * * This function attempts to lock an hwspinlock, and will immediately fail * if the hwspinlock is already taken. * * Upon a successful return from this function, preemption is disabled, * so the caller must not sleep, and is advised to release the hwspinlock * as soon as possible. This is required in order to minimize remote cores * polling on the hardware interconnect. * * Returns 0 if we successfully locked the hwspinlock, -EBUSY if * the hwspinlock was already taken, and -EINVAL if @hwlock is invalid. */
static inline int hwspin_trylock(struct hwspinlock *hwlock) { return __hwspin_trylock(hwlock, 0, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen22100.00%1100.00%
Total22100.00%1100.00%

/** * hwspin_lock_timeout_irqsave() - lock hwspinlock, with timeout, disable irqs * @hwlock: the hwspinlock to be locked * @to: timeout value in msecs * @flags: a pointer to where the caller's interrupt state will be saved at * * This function locks the underlying @hwlock. If the @hwlock * is already taken, the function will busy loop waiting for it to * be released, but give up when @timeout msecs have elapsed. * * Upon a successful return from this function, preemption and local interrupts * are disabled (plus previous interrupt state is saved), so the caller must * not sleep, and is advised to release the hwspinlock as soon as possible. * * Returns 0 when the @hwlock was successfully taken, and an appropriate * error code otherwise (most notably an -ETIMEDOUT if the @hwlock is still * busy after @timeout msecs). The function will never sleep. */
static inline int hwspin_lock_timeout_irqsave(struct hwspinlock *hwlock, unsigned int to, unsigned long *flags) { return __hwspin_lock_timeout(hwlock, to, HWLOCK_IRQSTATE, flags); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen33100.00%1100.00%
Total33100.00%1100.00%

/** * hwspin_lock_timeout_irq() - lock hwspinlock, with timeout, disable irqs * @hwlock: the hwspinlock to be locked * @to: timeout value in msecs * * This function locks the underlying @hwlock. If the @hwlock * is already taken, the function will busy loop waiting for it to * be released, but give up when @timeout msecs have elapsed. * * Upon a successful return from this function, preemption and local interrupts * are disabled so the caller must not sleep, and is advised to release the * hwspinlock as soon as possible. * * Returns 0 when the @hwlock was successfully taken, and an appropriate * error code otherwise (most notably an -ETIMEDOUT if the @hwlock is still * busy after @timeout msecs). The function will never sleep. */
static inline int hwspin_lock_timeout_irq(struct hwspinlock *hwlock, unsigned int to) { return __hwspin_lock_timeout(hwlock, to, HWLOCK_IRQ, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen28100.00%1100.00%
Total28100.00%1100.00%

/** * hwspin_lock_timeout() - lock an hwspinlock with timeout limit * @hwlock: the hwspinlock to be locked * @to: timeout value in msecs * * This function locks the underlying @hwlock. If the @hwlock * is already taken, the function will busy loop waiting for it to * be released, but give up when @timeout msecs have elapsed. * * Upon a successful return from this function, preemption is disabled * so the caller must not sleep, and is advised to release the hwspinlock * as soon as possible. * This is required in order to minimize remote cores polling on the * hardware interconnect. * * Returns 0 when the @hwlock was successfully taken, and an appropriate * error code otherwise (most notably an -ETIMEDOUT if the @hwlock is still * busy after @timeout msecs). The function will never sleep. */
static inline int hwspin_lock_timeout(struct hwspinlock *hwlock, unsigned int to) { return __hwspin_lock_timeout(hwlock, to, 0, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen28100.00%1100.00%
Total28100.00%1100.00%

/** * hwspin_unlock_irqrestore() - unlock hwspinlock, restore irq state * @hwlock: a previously-acquired hwspinlock which we want to unlock * @flags: previous caller's interrupt state to restore * * This function will unlock a specific hwspinlock, enable preemption and * restore the previous state of the local interrupts. It should be used * to undo, e.g., hwspin_trylock_irqsave(). * * @hwlock must be already locked before calling this function: it is a bug * to call unlock on a @hwlock that is already unlocked. */
static inline void hwspin_unlock_irqrestore(struct hwspinlock *hwlock, unsigned long *flags) { __hwspin_unlock(hwlock, HWLOCK_IRQSTATE, flags); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen26100.00%1100.00%
Total26100.00%1100.00%

/** * hwspin_unlock_irq() - unlock hwspinlock, enable interrupts * @hwlock: a previously-acquired hwspinlock which we want to unlock * * This function will unlock a specific hwspinlock, enable preemption and * enable local interrupts. Should be used to undo hwspin_lock_irq(). * * @hwlock must be already locked (e.g. by hwspin_trylock_irq()) before * calling this function: it is a bug to call unlock on a @hwlock that is * already unlocked. */
static inline void hwspin_unlock_irq(struct hwspinlock *hwlock) { __hwspin_unlock(hwlock, HWLOCK_IRQ, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen21100.00%1100.00%
Total21100.00%1100.00%

/** * hwspin_unlock() - unlock hwspinlock * @hwlock: a previously-acquired hwspinlock which we want to unlock * * This function will unlock a specific hwspinlock and enable preemption * back. * * @hwlock must be already locked (e.g. by hwspin_trylock()) before calling * this function: it is a bug to call unlock on a @hwlock that is already * unlocked. */
static inline void hwspin_unlock(struct hwspinlock *hwlock) { __hwspin_unlock(hwlock, 0, NULL); }

Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen21100.00%1100.00%
Total21100.00%1100.00%

#endif /* __LINUX_HWSPINLOCK_H */

Overall Contributors

PersonTokensPropCommitsCommitProp
ohad ben-cohenohad ben-cohen55293.72%350.00%
suman annasuman anna335.60%116.67%
paul gortmakerpaul gortmaker30.51%116.67%
axel linaxel lin10.17%116.67%
Total589100.00%6100.00%
Directory: include/linux
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
{% endraw %}