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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_ATOMIC_H_
#define _ASM_POWERPC_ATOMIC_H_
/*
* PowerPC atomic operations
*/
#ifdef __KERNEL__
#include <linux/types.h>
#include <asm/cmpxchg.h>
#include <asm/barrier.h>
#include <asm/asm-const.h>
/*
* Since *_return_relaxed and {cmp}xchg_relaxed are implemented with
* a "bne-" instruction at the end, so an isync is enough as a acquire barrier
* on the platform without lwsync.
*/
#define __atomic_acquire_fence() \
__asm__ __volatile__(PPC_ACQUIRE_BARRIER "" : : : "memory")
#define __atomic_release_fence() \
__asm__ __volatile__(PPC_RELEASE_BARRIER "" : : : "memory")
static __inline__ int arch_atomic_read(const atomic_t *v)
{
int t;
__asm__ __volatile__("lwz%U1%X1 %0,%1" : "=r"(t) : "m"UPD_CONSTR(v->counter));
return t;
}
static __inline__ void arch_atomic_set(atomic_t *v, int i)
{
__asm__ __volatile__("stw%U0%X0 %1,%0" : "=m"UPD_CONSTR(v->counter) : "r"(i));
}
#define ATOMIC_OP(op, asm_op) \
static __inline__ void arch_atomic_##op(int a, atomic_t *v) \
{ \
int t; \
\
__asm__ __volatile__( \
"1: lwarx %0,0,%3 # atomic_" #op "\n" \
#asm_op " %0,%2,%0\n" \
" stwcx. %0,0,%3 \n" \
" bne- 1b\n" \
: "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
} \
#define ATOMIC_OP_RETURN_RELAXED(op, asm_op) \
static inline int arch_atomic_##op##_return_relaxed(int a, atomic_t *v) \
{ \
int t; \
\
__asm__ __volatile__( \
"1: lwarx %0,0,%3 # atomic_" #op "_return_relaxed\n" \
#asm_op " %0,%2,%0\n" \
" stwcx. %0,0,%3\n" \
" bne- 1b\n" \
: "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
\
return t; \
}
#define ATOMIC_FETCH_OP_RELAXED(op, asm_op) \
static inline int arch_atomic_fetch_##op##_relaxed(int a, atomic_t *v) \
{ \
int res, t; \
\
__asm__ __volatile__( \
"1: lwarx %0,0,%4 # atomic_fetch_" #op "_relaxed\n" \
#asm_op " %1,%3,%0\n" \
" stwcx. %1,0,%4\n" \
" bne- 1b\n" \
: "=&r" (res), "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
\
return res; \
}
#define ATOMIC_OPS(op, asm_op) \
ATOMIC_OP(op, asm_op) \
ATOMIC_OP_RETURN_RELAXED(op, asm_op) \
ATOMIC_FETCH_OP_RELAXED(op, asm_op)
ATOMIC_OPS(add, add)
ATOMIC_OPS(sub, subf)
#define arch_atomic_add_return_relaxed arch_atomic_add_return_relaxed
#define arch_atomic_sub_return_relaxed arch_atomic_sub_return_relaxed
#define arch_atomic_fetch_add_relaxed arch_atomic_fetch_add_relaxed
#define arch_atomic_fetch_sub_relaxed arch_atomic_fetch_sub_relaxed
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, asm_op) \
ATOMIC_OP(op, asm_op) \
ATOMIC_FETCH_OP_RELAXED(op, asm_op)
ATOMIC_OPS(and, and)
ATOMIC_OPS(or, or)
ATOMIC_OPS(xor, xor)
#define arch_atomic_fetch_and_relaxed arch_atomic_fetch_and_relaxed
#define arch_atomic_fetch_or_relaxed arch_atomic_fetch_or_relaxed
#define arch_atomic_fetch_xor_relaxed arch_atomic_fetch_xor_relaxed
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP_RELAXED
#undef ATOMIC_OP_RETURN_RELAXED
#undef ATOMIC_OP
static __inline__ void arch_atomic_inc(atomic_t *v)
{
int t;
__asm__ __volatile__(
"1: lwarx %0,0,%2 # atomic_inc\n\
addic %0,%0,1\n"
" stwcx. %0,0,%2 \n\
bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
}
#define arch_atomic_inc arch_atomic_inc
static __inline__ int arch_atomic_inc_return_relaxed(atomic_t *v)
{
int t;
__asm__ __volatile__(
"1: lwarx %0,0,%2 # atomic_inc_return_relaxed\n"
" addic %0,%0,1\n"
" stwcx. %0,0,%2\n"
" bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
return t;
}
static __inline__ void arch_atomic_dec(atomic_t *v)
{
int t;
__asm__ __volatile__(
"1: lwarx %0,0,%2 # atomic_dec\n\
addic %0,%0,-1\n"
" stwcx. %0,0,%2\n\
bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
}
#define arch_atomic_dec arch_atomic_dec
static __inline__ int arch_atomic_dec_return_relaxed(atomic_t *v)
{
int t;
__asm__ __volatile__(
"1: lwarx %0,0,%2 # atomic_dec_return_relaxed\n"
" addic %0,%0,-1\n"
" stwcx. %0,0,%2\n"
" bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
return t;
}
#define arch_atomic_inc_return_relaxed arch_atomic_inc_return_relaxed
#define arch_atomic_dec_return_relaxed arch_atomic_dec_return_relaxed
#define arch_atomic_cmpxchg(v, o, n) \
(arch_cmpxchg(&((v)->counter), (o), (n)))
#define arch_atomic_cmpxchg_relaxed(v, o, n) \
arch_cmpxchg_relaxed(&((v)->counter), (o), (n))
#define arch_atomic_cmpxchg_acquire(v, o, n) \
arch_cmpxchg_acquire(&((v)->counter), (o), (n))
#define arch_atomic_xchg(v, new) \
(arch_xchg(&((v)->counter), new))
#define arch_atomic_xchg_relaxed(v, new) \
arch_xchg_relaxed(&((v)->counter), (new))
/*
* Don't want to override the generic atomic_try_cmpxchg_acquire, because
* we add a lock hint to the lwarx, which may not be wanted for the
* _acquire case (and is not used by the other _acquire variants so it
* would be a surprise).
*/
static __always_inline bool
arch_atomic_try_cmpxchg_lock(atomic_t *v, int *old, int new)
{
int r, o = *old;
__asm__ __volatile__ (
"1: lwarx %0,0,%2,%5 # atomic_try_cmpxchg_acquire \n"
" cmpw 0,%0,%3 \n"
" bne- 2f \n"
" stwcx. %4,0,%2 \n"
" bne- 1b \n"
"\t" PPC_ACQUIRE_BARRIER " \n"
"2: \n"
: "=&r" (r), "+m" (v->counter)
: "r" (&v->counter), "r" (o), "r" (new), "i" (IS_ENABLED(CONFIG_PPC64) ? 1 : 0)
: "cr0", "memory");
if (unlikely(r != o))
*old = r;
return likely(r == o);
}
/**
* atomic_fetch_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 arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
{
int t;
__asm__ __volatile__ (
PPC_ATOMIC_ENTRY_BARRIER
"1: lwarx %0,0,%1 # atomic_fetch_add_unless\n\
cmpw 0,%0,%3 \n\
beq 2f \n\
add %0,%2,%0 \n"
" stwcx. %0,0,%1 \n\
bne- 1b \n"
PPC_ATOMIC_EXIT_BARRIER
" subf %0,%2,%0 \n\
2:"
: "=&r" (t)
: "r" (&v->counter), "r" (a), "r" (u)
: "cc", "memory");
return t;
}
#define arch_atomic_fetch_add_unless arch_atomic_fetch_add_unless
/**
* atomic_inc_not_zero - increment unless the number is zero
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1, so long as @v is non-zero.
* Returns non-zero if @v was non-zero, and zero otherwise.
*/
static __inline__ int arch_atomic_inc_not_zero(atomic_t *v)
{
int t1, t2;
__asm__ __volatile__ (
PPC_ATOMIC_ENTRY_BARRIER
"1: lwarx %0,0,%2 # atomic_inc_not_zero\n\
cmpwi 0,%0,0\n\
beq- 2f\n\
addic %1,%0,1\n"
" stwcx. %1,0,%2\n\
bne- 1b\n"
PPC_ATOMIC_EXIT_BARRIER
"\n\
2:"
: "=&r" (t1), "=&r" (t2)
: "r" (&v->counter)
: "cc", "xer", "memory");
return t1;
}
#define arch_atomic_inc_not_zero(v) arch_atomic_inc_not_zero((v))
/*
* Atomically test *v and decrement if it is greater than 0.
* The function returns the old value of *v minus 1, even if
* the atomic variable, v, was not decremented.
*/
static __inline__ int arch_atomic_dec_if_positive(atomic_t *v)
{
int t;
__asm__ __volatile__(
PPC_ATOMIC_ENTRY_BARRIER
"1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
cmpwi %0,1\n\
addi %0,%0,-1\n\
blt- 2f\n"
" stwcx. %0,0,%1\n\
bne- 1b"
PPC_ATOMIC_EXIT_BARRIER
"\n\
2:" : "=&b" (t)
: "r" (&v->counter)
: "cc", "memory");
return t;
}
#define arch_atomic_dec_if_positive arch_atomic_dec_if_positive
#ifdef __powerpc64__
#define ATOMIC64_INIT(i) { (i) }
static __inline__ s64 arch_atomic64_read(const atomic64_t *v)
{
s64 t;
__asm__ __volatile__("ld%U1%X1 %0,%1" : "=r"(t) : "m"UPD_CONSTR(v->counter));
return t;
}
static __inline__ void arch_atomic64_set(atomic64_t *v, s64 i)
{
__asm__ __volatile__("std%U0%X0 %1,%0" : "=m"UPD_CONSTR(v->counter) : "r"(i));
}
#define ATOMIC64_OP(op, asm_op) \
static __inline__ void arch_atomic64_##op(s64 a, atomic64_t *v) \
{ \
s64 t; \
\
__asm__ __volatile__( \
"1: ldarx %0,0,%3 # atomic64_" #op "\n" \
#asm_op " %0,%2,%0\n" \
" stdcx. %0,0,%3 \n" \
" bne- 1b\n" \
: "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
}
#define ATOMIC64_OP_RETURN_RELAXED(op, asm_op) \
static inline s64 \
arch_atomic64_##op##_return_relaxed(s64 a, atomic64_t *v) \
{ \
s64 t; \
\
__asm__ __volatile__( \
"1: ldarx %0,0,%3 # atomic64_" #op "_return_relaxed\n" \
#asm_op " %0,%2,%0\n" \
" stdcx. %0,0,%3\n" \
" bne- 1b\n" \
: "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
\
return t; \
}
#define ATOMIC64_FETCH_OP_RELAXED(op, asm_op) \
static inline s64 \
arch_atomic64_fetch_##op##_relaxed(s64 a, atomic64_t *v) \
{ \
s64 res, t; \
\
__asm__ __volatile__( \
"1: ldarx %0,0,%4 # atomic64_fetch_" #op "_relaxed\n" \
#asm_op " %1,%3,%0\n" \
" stdcx. %1,0,%4\n" \
" bne- 1b\n" \
: "=&r" (res), "=&r" (t), "+m" (v->counter) \
: "r" (a), "r" (&v->counter) \
: "cc"); \
\
return res; \
}
#define ATOMIC64_OPS(op, asm_op) \
ATOMIC64_OP(op, asm_op) \
ATOMIC64_OP_RETURN_RELAXED(op, asm_op) \
ATOMIC64_FETCH_OP_RELAXED(op, asm_op)
ATOMIC64_OPS(add, add)
ATOMIC64_OPS(sub, subf)
#define arch_atomic64_add_return_relaxed arch_atomic64_add_return_relaxed
#define arch_atomic64_sub_return_relaxed arch_atomic64_sub_return_relaxed
#define arch_atomic64_fetch_add_relaxed arch_atomic64_fetch_add_relaxed
#define arch_atomic64_fetch_sub_relaxed arch_atomic64_fetch_sub_relaxed
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op, asm_op) \
ATOMIC64_OP(op, asm_op) \
ATOMIC64_FETCH_OP_RELAXED(op, asm_op)
ATOMIC64_OPS(and, and)
ATOMIC64_OPS(or, or)
ATOMIC64_OPS(xor, xor)
#define arch_atomic64_fetch_and_relaxed arch_atomic64_fetch_and_relaxed
#define arch_atomic64_fetch_or_relaxed arch_atomic64_fetch_or_relaxed
#define arch_atomic64_fetch_xor_relaxed arch_atomic64_fetch_xor_relaxed
#undef ATOPIC64_OPS
#undef ATOMIC64_FETCH_OP_RELAXED
#undef ATOMIC64_OP_RETURN_RELAXED
#undef ATOMIC64_OP
static __inline__ void arch_atomic64_inc(atomic64_t *v)
{
s64 t;
__asm__ __volatile__(
"1: ldarx %0,0,%2 # atomic64_inc\n\
addic %0,%0,1\n\
stdcx. %0,0,%2 \n\
bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
}
#define arch_atomic64_inc arch_atomic64_inc
static __inline__ s64 arch_atomic64_inc_return_relaxed(atomic64_t *v)
{
s64 t;
__asm__ __volatile__(
"1: ldarx %0,0,%2 # atomic64_inc_return_relaxed\n"
" addic %0,%0,1\n"
" stdcx. %0,0,%2\n"
" bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
return t;
}
static __inline__ void arch_atomic64_dec(atomic64_t *v)
{
s64 t;
__asm__ __volatile__(
"1: ldarx %0,0,%2 # atomic64_dec\n\
addic %0,%0,-1\n\
stdcx. %0,0,%2\n\
bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
}
#define arch_atomic64_dec arch_atomic64_dec
static __inline__ s64 arch_atomic64_dec_return_relaxed(atomic64_t *v)
{
s64 t;
__asm__ __volatile__(
"1: ldarx %0,0,%2 # atomic64_dec_return_relaxed\n"
" addic %0,%0,-1\n"
" stdcx. %0,0,%2\n"
" bne- 1b"
: "=&r" (t), "+m" (v->counter)
: "r" (&v->counter)
: "cc", "xer");
return t;
}
#define arch_atomic64_inc_return_relaxed arch_atomic64_inc_return_relaxed
#define arch_atomic64_dec_return_relaxed arch_atomic64_dec_return_relaxed
/*
* Atomically test *v and decrement if it is greater than 0.
* The function returns the old value of *v minus 1.
*/
static __inline__ s64 arch_atomic64_dec_if_positive(atomic64_t *v)
{
s64 t;
__asm__ __volatile__(
PPC_ATOMIC_ENTRY_BARRIER
"1: ldarx %0,0,%1 # atomic64_dec_if_positive\n\
addic. %0,%0,-1\n\
blt- 2f\n\
stdcx. %0,0,%1\n\
bne- 1b"
PPC_ATOMIC_EXIT_BARRIER
"\n\
2:" : "=&r" (t)
: "r" (&v->counter)
: "cc", "xer", "memory");
return t;
}
#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
#define arch_atomic64_cmpxchg(v, o, n) \
(arch_cmpxchg(&((v)->counter), (o), (n)))
#define arch_atomic64_cmpxchg_relaxed(v, o, n) \
arch_cmpxchg_relaxed(&((v)->counter), (o), (n))
#define arch_atomic64_cmpxchg_acquire(v, o, n) \
arch_cmpxchg_acquire(&((v)->counter), (o), (n))
#define arch_atomic64_xchg(v, new) \
(arch_xchg(&((v)->counter), new))
#define arch_atomic64_xchg_relaxed(v, new) \
arch_xchg_relaxed(&((v)->counter), (new))
/**
* atomic64_fetch_add_unless - add unless the number is 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 it was not @u.
* Returns the old value of @v.
*/
static __inline__ s64 arch_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
{
s64 t;
__asm__ __volatile__ (
PPC_ATOMIC_ENTRY_BARRIER
"1: ldarx %0,0,%1 # atomic64_fetch_add_unless\n\
cmpd 0,%0,%3 \n\
beq 2f \n\
add %0,%2,%0 \n"
" stdcx. %0,0,%1 \n\
bne- 1b \n"
PPC_ATOMIC_EXIT_BARRIER
" subf %0,%2,%0 \n\
2:"
: "=&r" (t)
: "r" (&v->counter), "r" (a), "r" (u)
: "cc", "memory");
return t;
}
#define arch_atomic64_fetch_add_unless arch_atomic64_fetch_add_unless
/**
* atomic_inc64_not_zero - increment unless the number is zero
* @v: pointer of type atomic64_t
*
* Atomically increments @v by 1, so long as @v is non-zero.
* Returns non-zero if @v was non-zero, and zero otherwise.
*/
static __inline__ int arch_atomic64_inc_not_zero(atomic64_t *v)
{
s64 t1, t2;
__asm__ __volatile__ (
PPC_ATOMIC_ENTRY_BARRIER
"1: ldarx %0,0,%2 # atomic64_inc_not_zero\n\
cmpdi 0,%0,0\n\
beq- 2f\n\
addic %1,%0,1\n\
stdcx. %1,0,%2\n\
bne- 1b\n"
PPC_ATOMIC_EXIT_BARRIER
"\n\
2:"
: "=&r" (t1), "=&r" (t2)
: "r" (&v->counter)
: "cc", "xer", "memory");
return t1 != 0;
}
#define arch_atomic64_inc_not_zero(v) arch_atomic64_inc_not_zero((v))
#endif /* __powerpc64__ */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_ATOMIC_H_ */
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