/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- atomic_add_return
- atomic_sub_return
- atomic_inc_return
- atomic_dec_return
- atomic_add_unless
- atomic_clear_mask
- atomic_set_mask
#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 <asm/assembler.h>
#include <asm/system.h>
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*/
/*
* Make sure gcc doesn't try to be clever and move things around
* on us. We need to use _exactly_ the address the user gave us,
* not some alias that contains the same information.
*/
typedef struct { volatile int counter; } atomic_t;
#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) ((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) (((v)->counter) = (i))
/**
* atomic_add_return - add integer to atomic variable and return it
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and return (@i + @v).
*/
static __inline__ int atomic_add_return(int i, atomic_t *v)
{
unsigned long flags;
int result;
local_irq_save(flags);
__asm__ __volatile__ (
"# atomic_add_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
M32R_LOCK" %0, @%1; \n\t"
"add %0, %2; \n\t"
M32R_UNLOCK" %0, @%1; \n\t"
: "=&r" (result)
: "r" (&v->counter), "r" (i)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
return result;
}
/**
* atomic_sub_return - subtract integer from atomic variable and return it
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v and return (@v - @i).
*/
static __inline__ int atomic_sub_return(int i, atomic_t *v)
{
unsigned long flags;
int result;
local_irq_save(flags);
__asm__ __volatile__ (
"# atomic_sub_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
M32R_LOCK" %0, @%1; \n\t"
"sub %0, %2; \n\t"
M32R_UNLOCK" %0, @%1; \n\t"
: "=&r" (result)
: "r" (&v->counter), "r" (i)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
return result;
}
/**
* atomic_add - add integer to atomic variable
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v.
*/
#define atomic_add(i,v) ((void) atomic_add_return((i), (v)))
/**
* atomic_sub - subtract the atomic variable
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v.
*/
#define atomic_sub(i,v) ((void) atomic_sub_return((i), (v)))
/**
* 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"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
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"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
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 non-zero if @v was not @u, and zero otherwise.
*/
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 != (u);
}
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t *addr)
{
unsigned long flags;
unsigned long tmp;
local_irq_save(flags);
__asm__ __volatile__ (
"# atomic_clear_mask \n\t"
DCACHE_CLEAR("%0", "r5", "%1")
M32R_LOCK" %0, @%1; \n\t"
"and %0, %2; \n\t"
M32R_UNLOCK" %0, @%1; \n\t"
: "=&r" (tmp)
: "r" (addr), "r" (~mask)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r5"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
}
static __inline__ void atomic_set_mask(unsigned long mask, atomic_t *addr)
{
unsigned long flags;
unsigned long tmp;
local_irq_save(flags);
__asm__ __volatile__ (
"# atomic_set_mask \n\t"
DCACHE_CLEAR("%0", "r5", "%1")
M32R_LOCK" %0, @%1; \n\t"
"or %0, %2; \n\t"
M32R_UNLOCK" %0, @%1; \n\t"
: "=&r" (tmp)
: "r" (addr), "r" (mask)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r5"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
}
/* Atomic operations are already serializing on m32r */
#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_M32R_ATOMIC_H */