diff options
Diffstat (limited to 'arch/powerpc/include/asm/atomic.h')
-rw-r--r-- | arch/powerpc/include/asm/atomic.h | 576 |
1 files changed, 576 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/atomic.h b/arch/powerpc/include/asm/atomic.h new file mode 100644 index 000000000..8a55eb8cc --- /dev/null +++ b/arch/powerpc/include/asm/atomic.h @@ -0,0 +1,576 @@ +/* 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> + +/* + * 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 atomic_read(const atomic_t *v) +{ + int t; + + __asm__ __volatile__("lwz%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter)); + + return t; +} + +static __inline__ void atomic_set(atomic_t *v, int i) +{ + __asm__ __volatile__("stw%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i)); +} + +#define ATOMIC_OP(op, asm_op) \ +static __inline__ void 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 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 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 atomic_add_return_relaxed atomic_add_return_relaxed +#define atomic_sub_return_relaxed atomic_sub_return_relaxed + +#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed +#define atomic_fetch_sub_relaxed 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 atomic_fetch_and_relaxed atomic_fetch_and_relaxed +#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed +#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed + +#undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP_RELAXED +#undef ATOMIC_OP_RETURN_RELAXED +#undef ATOMIC_OP + +static __inline__ void 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 atomic_inc atomic_inc + +static __inline__ int 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 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 atomic_dec atomic_dec + +static __inline__ int 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 atomic_inc_return_relaxed atomic_inc_return_relaxed +#define atomic_dec_return_relaxed atomic_dec_return_relaxed + +#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) +#define atomic_cmpxchg_relaxed(v, o, n) \ + cmpxchg_relaxed(&((v)->counter), (o), (n)) +#define atomic_cmpxchg_acquire(v, o, n) \ + cmpxchg_acquire(&((v)->counter), (o), (n)) + +#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) +#define atomic_xchg_relaxed(v, new) 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 +atomic_try_cmpxchg_lock(atomic_t *v, int *old, int new) +{ + int r, o = *old; + + __asm__ __volatile__ ( +"1:\t" PPC_LWARX(%0,0,%2,1) " # 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) + : "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 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 atomic_fetch_add_unless 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 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 atomic_inc_not_zero(v) 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 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 atomic_dec_if_positive atomic_dec_if_positive + +#ifdef __powerpc64__ + +#define ATOMIC64_INIT(i) { (i) } + +static __inline__ s64 atomic64_read(const atomic64_t *v) +{ + s64 t; + + __asm__ __volatile__("ld%U1%X1 %0,%1" : "=r"(t) : "m"(v->counter)); + + return t; +} + +static __inline__ void atomic64_set(atomic64_t *v, s64 i) +{ + __asm__ __volatile__("std%U0%X0 %1,%0" : "=m"(v->counter) : "r"(i)); +} + +#define ATOMIC64_OP(op, asm_op) \ +static __inline__ void 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 \ +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 \ +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 atomic64_add_return_relaxed atomic64_add_return_relaxed +#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed + +#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed +#define atomic64_fetch_sub_relaxed 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 atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed +#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed +#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed + +#undef ATOPIC64_OPS +#undef ATOMIC64_FETCH_OP_RELAXED +#undef ATOMIC64_OP_RETURN_RELAXED +#undef ATOMIC64_OP + +static __inline__ void 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 atomic64_inc atomic64_inc + +static __inline__ s64 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 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 atomic64_dec atomic64_dec + +static __inline__ s64 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 atomic64_inc_return_relaxed atomic64_inc_return_relaxed +#define atomic64_dec_return_relaxed 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 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 atomic64_dec_if_positive atomic64_dec_if_positive + +#define atomic64_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) +#define atomic64_cmpxchg_relaxed(v, o, n) \ + cmpxchg_relaxed(&((v)->counter), (o), (n)) +#define atomic64_cmpxchg_acquire(v, o, n) \ + cmpxchg_acquire(&((v)->counter), (o), (n)) + +#define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) +#define atomic64_xchg_relaxed(v, new) 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 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 atomic64_fetch_add_unless 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 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 atomic64_inc_not_zero(v) atomic64_inc_not_zero((v)) + +#endif /* __powerpc64__ */ + +#endif /* __KERNEL__ */ +#endif /* _ASM_POWERPC_ATOMIC_H_ */ |