/* $Id: atomic.h,v 1.3 2001/07/25 16:15:19 bjornw Exp $ */

#ifndef __ASM_CRIS_ATOMIC__
#define __ASM_CRIS_ATOMIC__

#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/cmpxchg.h>
#include <arch/atomic.h>

/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*/

#define ATOMIC_INIT(i) { (i) }

#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))

/* These should be written in asm but we do it in C for now. */

static inline void atomic_add(int i, volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
v->counter += i;
cris_atomic_restore(v, flags);
}

static inline void atomic_sub(int i, volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
v->counter -= i;
cris_atomic_restore(v, flags);
}

static inline int atomic_add_return(int i, volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = (v->counter += i);
cris_atomic_restore(v, flags);
return retval;
}

#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)

static inline int atomic_sub_return(int i, volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = (v->counter -= i);
cris_atomic_restore(v, flags);
return retval;
}

static inline int atomic_sub_and_test(int i, volatile atomic_t *v)
{
int retval;
unsigned long flags;
cris_atomic_save(v, flags);
retval = (v->counter -= i) == 0;
cris_atomic_restore(v, flags);
return retval;
}

static inline void atomic_inc(volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
(v->counter)++;
cris_atomic_restore(v, flags);
}

static inline void atomic_dec(volatile atomic_t *v)
{
unsigned long flags;
cris_atomic_save(v, flags);
(v->counter)--;
cris_atomic_restore(v, flags);
}

static inline int atomic_inc_return(volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = ++(v->counter);
cris_atomic_restore(v, flags);
return retval;
}

static inline int atomic_dec_return(volatile atomic_t *v)
{
unsigned long flags;
int retval;
cris_atomic_save(v, flags);
retval = --(v->counter);
cris_atomic_restore(v, flags);
return retval;
}
static inline int atomic_dec_and_test(volatile atomic_t *v)
{
int retval;
unsigned long flags;
cris_atomic_save(v, flags);
retval = --(v->counter) == 0;
cris_atomic_restore(v, flags);
return retval;
}

static inline int atomic_inc_and_test(volatile atomic_t *v)
{
int retval;
unsigned long flags;
cris_atomic_save(v, flags);
retval = ++(v->counter) == 0;
cris_atomic_restore(v, flags);
return retval;
}

static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
int ret;
unsigned long flags;

cris_atomic_save(v, flags);
ret = v->counter;
if (likely(ret == old))
v->counter = new;
cris_atomic_restore(v, flags);
return ret;
}

#define atomic_xchg(v, new) (xchg(&((v)->counter), new))

static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int ret;
unsigned long flags;

cris_atomic_save(v, flags);
ret = v->counter;
if (ret != u)
v->counter += a;
cris_atomic_restore(v, flags);
return ret;
}

/* 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()

#endif