/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* Do not include directly; use <linux/atomic.h>.
*/
#ifndef _ASM_TILE_ATOMIC_32_H
#define _ASM_TILE_ATOMIC_32_H
#include <asm/barrier.h>
#include <arch/chip.h>
#ifndef __ASSEMBLY__
/**
* atomic_add - add integer to atomic variable
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v.
*/
static inline void atomic_add(int i, atomic_t *v)
{
_atomic_xchg_add(&v->counter, i);
}
/**
* atomic_add_return - add integer and return
* @v: pointer of type atomic_t
* @i: integer value to add
*
* Atomically adds @i to @v and returns @i + @v
*/
static inline int atomic_add_return(int i, atomic_t *v)
{
smp_mb(); /* barrier for proper semantics */
return _atomic_xchg_add(&v->counter, i) + i;
}
/**
* __atomic_add_unless - add unless the number is already 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 @v was not already @u.
* Returns the old value of @v.
*/
static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
smp_mb(); /* barrier for proper semantics */
return _atomic_xchg_add_unless(&v->counter, a, u);
}
/**
* atomic_set - set atomic variable
* @v: pointer of type atomic_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*
* atomic_set() can't be just a raw store, since it would be lost if it
* fell between the load and store of one of the other atomic ops.
*/
static inline void atomic_set(atomic_t *v, int n)
{
_atomic_xchg(&v->counter, n);
}
/* A 64bit atomic type */
typedef struct {
long long counter;
} atomic64_t;
#define ATOMIC64_INIT(val) { (val) }
/**
* atomic64_read - read atomic variable
* @v: pointer of type atomic64_t
*
* Atomically reads the value of @v.
*/
static inline long long atomic64_read(const atomic64_t *v)
{
/*
* Requires an atomic op to read both 32-bit parts consistently.
* Casting away const is safe since the atomic support routines
* do not write to memory if the value has not been modified.
*/
return _atomic64_xchg_add((long long *)&v->counter, 0);
}
/**
* atomic64_add - add integer to atomic variable
* @i: integer value to add
* @v: pointer of type atomic64_t
*
* Atomically adds @i to @v.
*/
static inline void atomic64_add(long long i, atomic64_t *v)
{
_atomic64_xchg_add(&v->counter, i);
}
/**
* atomic64_add_return - add integer and return
* @v: pointer of type atomic64_t
* @i: integer value to add
*
* Atomically adds @i to @v and returns @i + @v
*/
static inline long long atomic64_add_return(long long i, atomic64_t *v)
{
smp_mb(); /* barrier for proper semantics */
return _atomic64_xchg_add(&v->counter, i) + i;
}
/**
* atomic64_add_unless - add unless the number is already a given value
* @v: pointer of type atomic64_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
static inline long long atomic64_add_unless(atomic64_t *v, long long a,
long long u)
{
smp_mb(); /* barrier for proper semantics */
return _atomic64_xchg_add_unless(&v->counter, a, u) != u;
}
/**
* atomic64_set - set atomic variable
* @v: pointer of type atomic64_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*
* atomic64_set() can't be just a raw store, since it would be lost if it
* fell between the load and store of one of the other atomic ops.
*/
static inline void atomic64_set(atomic64_t *v, long long n)
{
_atomic64_xchg(&v->counter, n);
}
#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
#define atomic64_inc(v) atomic64_add(1LL, (v))
#define atomic64_inc_return(v) atomic64_add_return(1LL, (v))
#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
#define atomic64_sub_return(i, v) atomic64_add_return(-(i), (v))
#define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0)
#define atomic64_sub(i, v) atomic64_add(-(i), (v))
#define atomic64_dec(v) atomic64_sub(1LL, (v))
#define atomic64_dec_return(v) atomic64_sub_return(1LL, (v))
#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL)
#endif /* !__ASSEMBLY__ */
/*
* Internal definitions only beyond this point.
*/
/*
* Number of atomic locks in atomic_locks[]. Must be a power of two.
* There is no reason for more than PAGE_SIZE / 8 entries, since that
* is the maximum number of pointer bits we can use to index this.
* And we cannot have more than PAGE_SIZE / 4, since this has to
* fit on a single page and each entry takes 4 bytes.
*/
#define ATOMIC_HASH_SHIFT (PAGE_SHIFT - 3)
#define ATOMIC_HASH_SIZE (1 << ATOMIC_HASH_SHIFT)
#ifndef __ASSEMBLY__
extern int atomic_locks[];
#endif
/*
* All the code that may fault while holding an atomic lock must
* place the pointer to the lock in ATOMIC_LOCK_REG so the fault code
* can correctly release and reacquire the lock. Note that we
* mention the register number in a comment in "lib/atomic_asm.S" to help
* assembly coders from using this register by mistake, so if it
* is changed here, change that comment as well.
*/
#define ATOMIC_LOCK_REG 20
#define ATOMIC_LOCK_REG_NAME r20
#ifndef __ASSEMBLY__
/* Called from setup to initialize a hash table to point to per_cpu locks. */
void __init_atomic_per_cpu(void);
#ifdef CONFIG_SMP
/* Support releasing the atomic lock in do_page_fault_ics(). */
void __atomic_fault_unlock(int *lock_ptr);
#endif
/* Return a pointer to the lock for the given address. */
int *__atomic_hashed_lock(volatile void *v);
/* Private helper routines in lib/atomic_asm_32.S */
struct __get_user {
unsigned long val;
int err;
};
extern struct __get_user __atomic_cmpxchg(volatile int *p,
int *lock, int o, int n);
extern struct __get_user __atomic_xchg(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xchg_add(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xchg_add_unless(volatile int *p,
int *lock, int o, int n);
extern struct __get_user __atomic_or(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_andn(volatile int *p, int *lock, int n);
extern struct __get_user __atomic_xor(volatile int *p, int *lock, int n);
extern long long __atomic64_cmpxchg(volatile long long *p, int *lock,
long long o, long long n);
extern long long __atomic64_xchg(volatile long long *p, int *lock, long long n);
extern long long __atomic64_xchg_add(volatile long long *p, int *lock,
long long n);
extern long long __atomic64_xchg_add_unless(volatile long long *p,
int *lock, long long o, long long n);
/* Return failure from the atomic wrappers. */
struct __get_user __atomic_bad_address(int __user *addr);
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_TILE_ATOMIC_32_H */
