/*
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#ifndef _ASM_MICROBLAZE_ATOMIC_H
#define _ASM_MICROBLAZE_ATOMIC_H
#include <linux/types.h>
#include <linux/compiler.h> /* likely */
#include <asm/system.h> /* local_irq_XXX and friends */
#define ATOMIC_INIT(i) { (i) }
#define atomic_read(v) ((v)->counter)
#define atomic_set(v, i) (((v)->counter) = (i))
#define atomic_inc(v) (atomic_add_return(1, (v)))
#define atomic_dec(v) (atomic_sub_return(1, (v)))
#define atomic_add(i, v) (atomic_add_return(i, (v)))
#define atomic_sub(i, v) (atomic_sub_return(i, (v)))
#define atomic_inc_return(v) (atomic_add_return(1, (v)))
#define atomic_dec_return(v) (atomic_sub_return(1, (v)))
#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
#define atomic_inc_not_zero(v) (atomic_add_unless((v), 1, 0))
#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
unsigned long flags;
local_irq_save(flags);
ret = v->counter;
if (likely(ret == old))
v->counter = new;
local_irq_restore(flags);
return ret;
}
static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
c = old;
return c != u;
}
static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
{
unsigned long flags;
local_irq_save(flags);
*addr &= ~mask;
local_irq_restore(flags);
}
/**
* atomic_add_return - add and return
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and returns @i + @v
*/
static inline int atomic_add_return(int i, atomic_t *v)
{
unsigned long flags;
int val;
local_irq_save(flags);
val = v->counter;
v->counter = val += i;
local_irq_restore(flags);
return val;
}
static inline int atomic_sub_return(int i, atomic_t *v)
{
return atomic_add_return(-i, v);
}
/*
* Atomically test *v and decrement if it is greater than 0.
* The function returns the old value of *v minus 1.
*/
static inline int atomic_dec_if_positive(atomic_t *v)
{
unsigned long flags;
int res;
local_irq_save(flags);
res = v->counter - 1;
if (res >= 0)
v->counter = res;
local_irq_restore(flags);
return res;
}
#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/* Atomic operations are already serializing */
#define smp_mb__before_atomic_dec() barrier()
#define smp_mb__after_atomic_dec() barrier()
#define smp_mb__before_atomic_inc() barrier()
#define smp_mb__after_atomic_inc() barrier()
#include <asm-generic/atomic.h>
#endif /* _ASM_MICROBLAZE_ATOMIC_H */
