freebsd-dev/sys/powerpc/include/atomic.h
Benno Rice 7a0e745f1a Don't initialise ret in atomic_cmpset_32.
Add more synchronisation.
2001-06-26 13:54:17 +00:00

472 lines
12 KiB
C

/*-
* Copyright (c) 2001 Benno Rice
* Copyright (c) 2001 David E. O'Brien
* Copyright (c) 1998 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _MACHINE_ATOMIC_H_
#define _MACHINE_ATOMIC_H_
#include <machine/cpufunc.h>
/*
* Various simple arithmetic on memory which is atomic in the presence
* of interrupts and SMP safe.
*/
void atomic_set_8(volatile u_int8_t *, u_int8_t);
void atomic_clear_8(volatile u_int8_t *, u_int8_t);
void atomic_add_8(volatile u_int8_t *, u_int8_t);
void atomic_subtract_8(volatile u_int8_t *, u_int8_t);
void atomic_set_16(volatile u_int16_t *, u_int16_t);
void atomic_clear_16(volatile u_int16_t *, u_int16_t);
void atomic_add_16(volatile u_int16_t *, u_int16_t);
void atomic_subtract_16(volatile u_int16_t *, u_int16_t);
static __inline void
atomic_set_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
__asm __volatile (
"1:\tlwarx %0, 0, %2\n\t" /* load old value */
"or %0, %0, %3\n\t" /* calculate new value */
"stwcx. %0, 0, %1\n\t" /* attempt to store */
"bne- 1\n\t" /* spin if failed */
"eieio\n" /* drain to memory */
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline void
atomic_clear_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
__asm __volatile (
"1:\tlwarx %0, 0, %2\n\t" /* load old value */
"andc %0, %0, %3\n\t" /* calculate new value */
"stwcx. %0, 0, %1\n\t" /* attempt to store */
"bne- 1\n\t" /* spin if failed */
"eieio\n" /* drain to memory */
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline void
atomic_add_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
__asm __volatile (
"1:\tlwarx %0, 0, %2\n\t" /* load old value */
"add %0, %0, %3\n\t" /* calculate new value */
"stwcx. %0, 0, %1\n\t" /* attempt to store */
"bne- 1\n\t" /* spin if failed */
"eieio\n" /* Old McDonald had a farm */
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline void
atomic_subtract_32(volatile u_int32_t *p, u_int32_t v)
{
u_int32_t temp;
__asm __volatile (
"1:\tlwarx %0, 0, %2\n\t" /* load old value */
"sub %0, %3, %0\n\t" /* calculate new value */
"stwcx. %0, 0, %1\n\t" /* attempt to store */
"bne- 1\n\t" /* spin if failed */
"eieio\n" /* drain to memory */
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline u_int32_t
atomic_readandclear_32(volatile u_int32_t *addr)
{
u_int32_t result,temp;
__asm __volatile (
"\teieio\n" /* memory barrier */
"1:\tlwarx %0, 0, %3\n\t" /* load old value */
"li %1, 0\n\t" /* load new value */
"stwcx. %1, 0, %2\n\t" /* attempt to store */
"bne- 1\n\t" /* spin if failed */
"eieio\n" /* drain to memory */
: "=&r"(result), "=&r"(temp), "=r" (*addr)
: "r"(*addr)
: "memory");
return result;
}
#if 0
/*
* So far I haven't found a way to implement atomic 64-bit ops on the
* 32-bit PowerPC without involving major headaches. If anyone has
* any ideas, please let me know. =)
* - benno@FreeBSD.org
*/
static __inline void
atomic_set_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
__asm __volatile (
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline void
atomic_clear_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
__asm __volatile (
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline void
atomic_add_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
__asm __volatile (
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline void
atomic_subtract_64(volatile u_int64_t *p, u_int64_t v)
{
u_int64_t temp;
__asm __volatile (
: "=&r" (temp), "=r" (*p)
: "r" (*p), "r" (v)
: "memory");
}
static __inline u_int64_t
atomic_readandclear_64(volatile u_int64_t *addr)
{
u_int64_t result,temp;
__asm __volatile (
: "=&r"(result), "=&r"(temp), "=r" (*addr)
: "r"(*addr)
: "memory");
return result;
}
#endif /* 0 */
#define atomic_set_char atomic_set_8
#define atomic_clear_char atomic_clear_8
#define atomic_add_char atomic_add_8
#define atomic_subtract_char atomic_subtract_8
#define atomic_set_short atomic_set_16
#define atomic_clear_short atomic_clear_16
#define atomic_add_short atomic_add_16
#define atomic_subtract_short atomic_subtract_16
#define atomic_set_int atomic_set_32
#define atomic_clear_int atomic_clear_32
#define atomic_add_int atomic_add_32
#define atomic_subtract_int atomic_subtract_32
#define atomic_readandclear_int atomic_readandclear_32
#define atomic_set_long atomic_set_32
#define atomic_clear_long atomic_clear_32
#define atomic_add_long(p, v) atomic_add_32((u_int32_t *)p, (u_int32_t)v)
#define atomic_subtract_long atomic_subtract_32
#define atomic_readandclear_long atomic_readandclear_32
#if 0
/* See above. */
#define atomic_set_long_long atomic_set_64
#define atomic_clear_long_long atomic_clear_64
#define atomic_add_long_long atomic_add_64
#define atomic_subtract_long_long atomic_subtract_64
#define atomic_readandclear_long_long atomic_readandclear_64
#endif /* 0 */
#define ATOMIC_ACQ_REL(NAME, WIDTH, TYPE) \
static __inline void \
atomic_##NAME##_acq_##WIDTH(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v) \
{ \
powerpc_mb(); \
atomic_##NAME##_##WIDTH(p, v); \
} \
\
static __inline void \
atomic_##NAME##_rel_##WIDTH(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v) \
{ \
atomic_##NAME##_##WIDTH(p, v); \
powerpc_mb(); \
} \
\
static __inline void \
atomic_##NAME##_acq_##TYPE(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v) \
{ \
powerpc_mb(); \
atomic_##NAME##_##WIDTH(p, v); \
} \
\
static __inline void \
atomic_##NAME##_rel_##TYPE(volatile u_int##WIDTH##_t *p, u_int##WIDTH##_t v) \
{ \
atomic_##NAME##_##WIDTH(p, v); \
powerpc_mb(); \
}
ATOMIC_ACQ_REL(set, 8, char)
ATOMIC_ACQ_REL(clear, 8, char)
ATOMIC_ACQ_REL(add, 8, char)
ATOMIC_ACQ_REL(subtract, 8, char)
ATOMIC_ACQ_REL(set, 16, short)
ATOMIC_ACQ_REL(clear, 16, short)
ATOMIC_ACQ_REL(add, 16, short)
ATOMIC_ACQ_REL(subtract, 16, short)
ATOMIC_ACQ_REL(set, 32, int)
ATOMIC_ACQ_REL(clear, 32, int)
ATOMIC_ACQ_REL(add, 32, int)
ATOMIC_ACQ_REL(subtract, 32, int)
#define atomic_set_acq_long atomic_set_acq_32
#define atomic_set_rel_long atomic_set_rel_32
#define atomic_clear_acq_long atomic_clear_acq_32
#define atomic_clear_rel_long atomic_clear_rel_32
#define atomic_add_acq_long atomic_add_acq_32
#define atomic_add_rel_long atomic_add_rel_32
#define atomic_subtract_acq_long atomic_subtract_acq_32
#define atomic_subtract_rel_long atomic_subtract_rel_32
#undef ATOMIC_ACQ_REL
/*
* We assume that a = b will do atomic loads and stores.
*/
#define ATOMIC_STORE_LOAD(TYPE, WIDTH) \
static __inline u_##TYPE \
atomic_load_acq_##WIDTH(volatile u_##TYPE *p) \
{ \
powerpc_mb(); \
return (*p); \
} \
\
static __inline void \
atomic_store_rel_##WIDTH(volatile u_##TYPE *p, u_##TYPE v) \
{ \
*p = v; \
powerpc_mb(); \
} \
static __inline u_##TYPE \
atomic_load_acq_##TYPE(volatile u_##TYPE *p) \
{ \
powerpc_mb(); \
return (*p); \
} \
\
static __inline void \
atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v) \
{ \
*p = v; \
powerpc_mb(); \
}
ATOMIC_STORE_LOAD(char, 8)
ATOMIC_STORE_LOAD(short, 16)
ATOMIC_STORE_LOAD(int, 32)
#define atomic_load_acq_long atomic_load_acq_32
#define atomic_store_rel_long atomic_store_rel_32
#undef ATOMIC_STORE_LOAD
/*
* Atomically compare the value stored at *p with cmpval and if the
* two values are equal, update the value of *p with newval. Returns
* zero if the compare failed, nonzero otherwise.
*/
static __inline u_int32_t
atomic_cmpset_32(volatile u_int32_t* p, u_int32_t cmpval, u_int32_t newval)
{
u_int32_t ret;
__asm __volatile (
"1:\tlwarx %0, 0, %3\n\t" /* load old value */
"cmplw 0, %1, %0\n\t" /* compare */
"bne 2f\n\t" /* exit if not equal */
"mr %0, %2\n\t" /* value to store */
"stwcx. %0, 0, %3\n\t" /* attempt to store */
"bne- 1b\n\t" /* spin if failed */
"eieio\n" /* memory barrier */
"sync\n"
"2:\t\n"
: "=&r" (ret)
: "r" (cmpval), "r" (newval), "r" (p)
: "memory");
return ret;
}
#if 0
/*
* Atomically compare the value stored at *p with cmpval and if the
* two values are equal, update the value of *p with newval. Returns
* zero if the compare failed, nonzero otherwise.
*/
static __inline u_int64_t
atomic_cmpset_64(volatile u_int64_t* p, u_int64_t cmpval, u_int64_t newval)
{
u_int64_t ret;
__asm __volatile (
: "=&r" (ret), "=r" (*p)
: "r" (cmpval), "r" (newval), "r" (*p)
: "memory");
return ret;
}
#endif /* 0 */
#define atomic_cmpset_int atomic_cmpset_32
#define atomic_cmpset_long atomic_cmpset_32
#if 0
#define atomic_cmpset_long_long atomic_cmpset_64
#endif /* 0 */
static __inline int
atomic_cmpset_ptr(volatile void *dst, void *exp, void *src)
{
return (atomic_cmpset_32((volatile u_int32_t *)dst, (u_int32_t)exp,
(u_int32_t)src));
}
static __inline u_int32_t
atomic_cmpset_acq_32(volatile u_int32_t *p, u_int32_t cmpval, u_int32_t newval)
{
powerpc_mb();
return (atomic_cmpset_32(p, cmpval, newval));
}
static __inline u_int32_t
atomic_cmpset_rel_32(volatile u_int32_t *p, u_int32_t cmpval, u_int32_t newval)
{
int retval;
retval = atomic_cmpset_32(p, cmpval, newval);
powerpc_mb();
return (retval);
}
#define atomic_cmpset_acq_int atomic_cmpset_acq_32
#define atomic_cmpset_rel_int atomic_cmpset_rel_32
#define atomic_cmpset_acq_long atomic_cmpset_acq_32
#define atomic_cmpset_rel_long atomic_cmpset_rel_32
static __inline int
atomic_cmpset_acq_ptr(volatile void *dst, void *exp, void *src)
{
return (atomic_cmpset_acq_32((volatile u_int32_t *)dst,
(u_int32_t)exp, (u_int32_t)src));
}
static __inline int
atomic_cmpset_rel_ptr(volatile void *dst, void *exp, void *src)
{
return (atomic_cmpset_rel_32((volatile u_int32_t *)dst,
(u_int32_t)exp, (u_int32_t)src));
}
static __inline void *
atomic_load_acq_ptr(volatile void *p)
{
return (void *)atomic_load_acq_32((volatile u_int32_t *)p);
}
static __inline void
atomic_store_rel_ptr(volatile void *p, void *v)
{
atomic_store_rel_32((volatile u_int32_t *)p, (u_int32_t)v);
}
#define ATOMIC_PTR(NAME) \
static __inline void \
atomic_##NAME##_ptr(volatile void *p, uintptr_t v) \
{ \
atomic_##NAME##_32((volatile u_int32_t *)p, v); \
} \
\
static __inline void \
atomic_##NAME##_acq_ptr(volatile void *p, uintptr_t v) \
{ \
atomic_##NAME##_acq_32((volatile u_int32_t *)p, v); \
} \
\
static __inline void \
atomic_##NAME##_rel_ptr(volatile void *p, uintptr_t v) \
{ \
atomic_##NAME##_rel_32((volatile u_int32_t *)p, v); \
}
ATOMIC_PTR(set)
ATOMIC_PTR(clear)
ATOMIC_PTR(add)
ATOMIC_PTR(subtract)
#undef ATOMIC_PTR
#endif /* ! _MACHINE_ATOMIC_H_ */