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/*
 * Copyright (c) 2012, ARM Limited. All rights reserved.
 *       
 * Redistribution and use in source and binary forms, with
 * or without modification, are permitted provided that the
 * following conditions are met:
 *     
 * Redistributions of source code must retain the above
 * copyright notice, this list of conditions and the 
 * following disclaimer.
 *
 * Redistributions in binary form must reproduce the
 * above copyright notice, this list of conditions and 
 * the following disclaimer in the documentation 
 * and/or other materials provided with the distribution.
 *      
 * Neither the name of ARM nor the names of its
 * contributors may be used to endorse or promote products
 * derived from this software without specific prior written
 * permission.                        
 */ 
#ifndef _BAKERY_H_
#define _BAKERY_H_

#define MAX_CPUS 4

/* 
 * Bakery structure - declare/allocate one of these for each lock.
 * A pointer to this struct is passed to the lock/unlock functions.
 */
typedef struct {
        volatile char entering[MAX_CPUS];
        volatile unsigned number[MAX_CPUS];
} bakery_t;

/*
 * Initialize a bakery - only required if the bakery_t is
 * on the stack or heap, as static data is zeroed anyway.
 */
extern void init_bakery_spinlock(bakery_t * bakery);

/*
 * Claim a bakery lock. Function does not return until
 * lock has been obtained.
 */
extern void get_bakery_spinlock(unsigned cpuid, bakery_t * bakery);

/*
 * Release a bakery lock.
 */
extern void release_bakery_spinlock(unsigned cpuid, bakery_t * bakery);

#endif /* _BAKERY_H_ */