- 根目录:
- arch
- m32r
- include
- asm
- local.h
#ifndef __M32R_LOCAL_H
#define __M32R_LOCAL_H
/*
* linux/include/asm-m32r/local.h
*
* M32R version:
* Copyright (C) 2001, 2002 Hitoshi Yamamoto
* Copyright (C) 2004 Hirokazu Takata <takata at linux-m32r.org>
* Copyright (C) 2007 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
*/
#include <linux/percpu.h>
#include <asm/assembler.h>
#include <asm/system.h>
#include <asm/local.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; } local_t;
#define LOCAL_INIT(i) { (i) }
/**
* local_read - read local variable
* @l: pointer of type local_t
*
* Atomically reads the value of @l.
*/
#define local_read(l) ((l)->counter)
/**
* local_set - set local variable
* @l: pointer of type local_t
* @i: required value
*
* Atomically sets the value of @l to @i.
*/
#define local_set(l, i) (((l)->counter) = (i))
/**
* local_add_return - add long to local variable and return it
* @i: long value to add
* @l: pointer of type local_t
*
* Atomically adds @i to @l and return (@i + @l).
*/
static inline long local_add_return(long i, local_t *l)
{
unsigned long flags;
long result;
local_irq_save(flags);
__asm__ __volatile__ (
"# local_add_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
"ld %0, @%1; \n\t"
"add %0, %2; \n\t"
"st %0, @%1; \n\t"
: "=&r" (result)
: "r" (&l->counter), "r" (i)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
return result;
}
/**
* local_sub_return - subtract long from local variable and return it
* @i: long value to subtract
* @l: pointer of type local_t
*
* Atomically subtracts @i from @l and return (@l - @i).
*/
static inline long local_sub_return(long i, local_t *l)
{
unsigned long flags;
long result;
local_irq_save(flags);
__asm__ __volatile__ (
"# local_sub_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
"ld %0, @%1; \n\t"
"sub %0, %2; \n\t"
"st %0, @%1; \n\t"
: "=&r" (result)
: "r" (&l->counter), "r" (i)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
return result;
}
/**
* local_add - add long to local variable
* @i: long value to add
* @l: pointer of type local_t
*
* Atomically adds @i to @l.
*/
#define local_add(i, l) ((void) local_add_return((i), (l)))
/**
* local_sub - subtract the local variable
* @i: long value to subtract
* @l: pointer of type local_t
*
* Atomically subtracts @i from @l.
*/
#define local_sub(i, l) ((void) local_sub_return((i), (l)))
/**
* local_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @l: pointer of type local_t
*
* Atomically subtracts @i from @l and returns
* true if the result is zero, or false for all
* other cases.
*/
#define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0)
/**
* local_inc_return - increment local variable and return it
* @l: pointer of type local_t
*
* Atomically increments @l by 1 and returns the result.
*/
static inline long local_inc_return(local_t *l)
{
unsigned long flags;
long result;
local_irq_save(flags);
__asm__ __volatile__ (
"# local_inc_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
"ld %0, @%1; \n\t"
"addi %0, #1; \n\t"
"st %0, @%1; \n\t"
: "=&r" (result)
: "r" (&l->counter)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
return result;
}
/**
* local_dec_return - decrement local variable and return it
* @l: pointer of type local_t
*
* Atomically decrements @l by 1 and returns the result.
*/
static inline long local_dec_return(local_t *l)
{
unsigned long flags;
long result;
local_irq_save(flags);
__asm__ __volatile__ (
"# local_dec_return \n\t"
DCACHE_CLEAR("%0", "r4", "%1")
"ld %0, @%1; \n\t"
"addi %0, #-1; \n\t"
"st %0, @%1; \n\t"
: "=&r" (result)
: "r" (&l->counter)
: "memory"
#ifdef CONFIG_CHIP_M32700_TS1
, "r4"
#endif /* CONFIG_CHIP_M32700_TS1 */
);
local_irq_restore(flags);
return result;
}
/**
* local_inc - increment local variable
* @l: pointer of type local_t
*
* Atomically increments @l by 1.
*/
#define local_inc(l) ((void)local_inc_return(l))
/**
* local_dec - decrement local variable
* @l: pointer of type local_t
*
* Atomically decrements @l by 1.
*/
#define local_dec(l) ((void)local_dec_return(l))
/**
* local_inc_and_test - increment and test
* @l: pointer of type local_t
*
* Atomically increments @l by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
#define local_inc_and_test(l) (local_inc_return(l) == 0)
/**
* local_dec_and_test - decrement and test
* @l: pointer of type local_t
*
* Atomically decrements @l by 1 and
* returns true if the result is 0, or false for all
* other cases.
*/
#define local_dec_and_test(l) (local_dec_return(l) == 0)
/**
* local_add_negative - add and test if negative
* @l: pointer of type local_t
* @i: integer value to add
*
* Atomically adds @i to @l and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
#define local_add_negative(i, l) (local_add_return((i), (l)) < 0)
#define local_cmpxchg(l, o, n) (cmpxchg_local(&((l)->counter), (o), (n)))
#define local_xchg(v, new) (xchg_local(&((l)->counter), new))
/**
* local_add_unless - add unless the number is a given value
* @l: pointer of type local_t
* @a: the amount to add to l...
* @u: ...unless l is equal to u.
*
* Atomically adds @a to @l, so long as it was not @u.
* Returns non-zero if @l was not @u, and zero otherwise.
*/
static inline int local_add_unless(local_t *l, long a, long u)
{
long c, old;
c = local_read(l);
for (;;) {
if (unlikely(c == (u)))
break;
old = local_cmpxchg((l), c, c + (a));
if (likely(old == c))
break;
c = old;
}
return c != (u);
}
#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
static inline void local_clear_mask(unsigned long mask, local_t *addr)
{
unsigned long flags;
unsigned long tmp;
local_irq_save(flags);
__asm__ __volatile__ (
"# local_clear_mask \n\t"
DCACHE_CLEAR("%0", "r5", "%1")
"ld %0, @%1; \n\t"
"and %0, %2; \n\t"
"st %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 local_set_mask(unsigned long mask, local_t *addr)
{
unsigned long flags;
unsigned long tmp;
local_irq_save(flags);
__asm__ __volatile__ (
"# local_set_mask \n\t"
DCACHE_CLEAR("%0", "r5", "%1")
"ld %0, @%1; \n\t"
"or %0, %2; \n\t"
"st %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_local_dec() barrier()
#define smp_mb__after_local_dec() barrier()
#define smp_mb__before_local_inc() barrier()
#define smp_mb__after_local_inc() barrier()
/* Use these for per-cpu local_t variables: on some archs they are
* much more efficient than these naive implementations. Note they take
* a variable, not an address.
*/
#define __local_inc(l) ((l)->a.counter++)
#define __local_dec(l) ((l)->a.counter++)
#define __local_add(i, l) ((l)->a.counter += (i))
#define __local_sub(i, l) ((l)->a.counter -= (i))
/* Use these for per-cpu local_t variables: on some archs they are
* much more efficient than these naive implementations. Note they take
* a variable, not an address.
*/
#endif /* __M32R_LOCAL_H */