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#ifndef _ASM_M32R_ATOMIC_H
#define _ASM_M32R_ATOMIC_H
/*
* linux/include/asm-m32r/atomic.h
*
* M32R version:
* Copyright (C) 2001, 2002 Hitoshi Yamamoto
* Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
*/
#include <linux/types.h>
#include <asm/assembler.h>
#include <asm/cmpxchg.h>
#include <asm/dcache_clear.h>
#include <asm/barrier.h>
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*/
#define ATOMIC_INIT(i) { (i) }
/**
* atomic_read - read atomic variable
* @v: pointer of type atomic_t
*
* Atomically reads the value of @v.
*/
#define atomic_read(v) READ_ONCE((v)->counter)
/**
* atomic_set - set atomic variable
* @v: pointer of type atomic_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*/
#define atomic_set(v,i) WRITE_ONCE(((v)->counter), (i))
#ifdef CONFIG_CHIP_M32700_TS1
#define __ATOMIC_CLOBBER , "r4"
#else
#define __ATOMIC_CLOBBER
#endif
#define ATOMIC_OP(op) \
static __inline__ void atomic_##op(int i, atomic_t *v) \
{ \
unsigned long flags; \
int result; \
\
local_irq_save(flags); \
__asm__ __volatile__ ( \
"# atomic_" #op " \n\t" \
DCACHE_CLEAR("%0", "r4", "%1") \
M32R_LOCK" %0, @%1; \n\t" \
#op " %0, %2; \n\t" \
M32R_UNLOCK" %0, @%1; \n\t" \
: "=&r" (result) \
: "r" (&v->counter), "r" (i) \
: "memory" \
__ATOMIC_CLOBBER \
); \
local_irq_restore(flags); \
} \
#define ATOMIC_OP_RETURN(op) \
static __inline__ int atomic_##op##_return(int i, atomic_t *v) \
{ \
unsigned long flags; \
int result; \
\
local_irq_save(flags); \
__asm__ __volatile__ ( \
"# atomic_" #op "_return \n\t" \
DCACHE_CLEAR("%0", "r4", "%1") \
M32R_LOCK" %0, @%1; \n\t" \
#op " %0, %2; \n\t" \
M32R_UNLOCK" %0, @%1; \n\t" \
: "=&r" (result) \
: "r" (&v->counter), "r" (i) \
: "memory" \
__ATOMIC_CLOBBER \
); \
local_irq_restore(flags); \
\
return result; \
}
#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)
#undef ATOMIC_OPS
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
/**
* atomic_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
*/
#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
/**
* atomic_inc_return - increment atomic variable and return it
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1 and returns the result.
*/
static __inline__ int atomic_inc_return(atomic_t *v)
{
unsigned long flags;
int result;
local_irq_save(flags);
__asm__ __volatile__ (
"# atomic_inc_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
M32R_LOCK" %0, @%1; \n\t"
"addi %0, #1; \n\t"
M32R_UNLOCK" %0, @%1; \n\t"
: "=&r" (result)
: "r" (&v->counter)
: "memory"
__ATOMIC_CLOBBER
);
local_irq_restore(flags);
return result;
}
/**
* atomic_dec_return - decrement atomic variable and return it
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1 and returns the result.
*/
static __inline__ int atomic_dec_return(atomic_t *v)
{
unsigned long flags;
int result;
local_irq_save(flags);
__asm__ __volatile__ (
"# atomic_dec_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
M32R_LOCK" %0, @%1; \n\t"
"addi %0, #-1; \n\t"
M32R_UNLOCK" %0, @%1; \n\t"
: "=&r" (result)
: "r" (&v->counter)
: "memory"
__ATOMIC_CLOBBER
);
local_irq_restore(flags);
return result;
}
/**
* atomic_inc - increment atomic variable
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1.
*/
#define atomic_inc(v) ((void)atomic_inc_return(v))
/**
* atomic_dec - decrement atomic variable
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1.
*/
#define atomic_dec(v) ((void)atomic_dec_return(v))
/**
* atomic_inc_and_test - increment and test
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
/**
* atomic_dec_and_test - decrement and test
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1 and
* returns true if the result is 0, or false for all
* other cases.
*/
#define atomic_dec_and_test(v) (atomic_dec_return(v) == 0)
/**
* atomic_add_negative - add and test if negative
* @v: pointer of type atomic_t
* @i: integer value to add
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
#define atomic_add_negative(i,v) (atomic_add_return((i), (v)) < 0)
#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
* __atomic_add_unless - add unless the number is a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns the old value of @v.
*/
static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
for (;;) {
if (unlikely(c == (u)))
break;
old = atomic_cmpxchg((v), c, c + (a));
if (likely(old == c))
break;
c = old;
}
return c;
}
#endif /* _ASM_M32R_ATOMIC_H */
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