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-rw-r--r--arch/powerpc/include/asm/atomic.h489
1 files changed, 489 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..486ab7889
--- /dev/null
+++ b/arch/powerpc/include/asm/atomic.h
@@ -0,0 +1,489 @@
+/* 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<>"(v->counter));
+
+ return t;
+}
+
+static __inline__ void arch_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, suffix, sign, ...) \
+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 "%I2" suffix " %0,%0,%2\n" \
+" stwcx. %0,0,%3 \n" \
+" bne- 1b\n" \
+ : "=&r" (t), "+m" (v->counter) \
+ : "r"#sign (a), "r" (&v->counter) \
+ : "cc", ##__VA_ARGS__); \
+} \
+
+#define ATOMIC_OP_RETURN_RELAXED(op, asm_op, suffix, sign, ...) \
+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 "%I2" suffix " %0,%0,%2\n" \
+" stwcx. %0,0,%3\n" \
+" bne- 1b\n" \
+ : "=&r" (t), "+m" (v->counter) \
+ : "r"#sign (a), "r" (&v->counter) \
+ : "cc", ##__VA_ARGS__); \
+ \
+ return t; \
+}
+
+#define ATOMIC_FETCH_OP_RELAXED(op, asm_op, suffix, sign, ...) \
+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 "%I3" suffix " %1,%0,%3\n" \
+" stwcx. %1,0,%4\n" \
+" bne- 1b\n" \
+ : "=&r" (res), "=&r" (t), "+m" (v->counter) \
+ : "r"#sign (a), "r" (&v->counter) \
+ : "cc", ##__VA_ARGS__); \
+ \
+ return res; \
+}
+
+#define ATOMIC_OPS(op, asm_op, suffix, sign, ...) \
+ ATOMIC_OP(op, asm_op, suffix, sign, ##__VA_ARGS__) \
+ ATOMIC_OP_RETURN_RELAXED(op, asm_op, suffix, sign, ##__VA_ARGS__)\
+ ATOMIC_FETCH_OP_RELAXED(op, asm_op, suffix, sign, ##__VA_ARGS__)
+
+ATOMIC_OPS(add, add, "c", I, "xer")
+ATOMIC_OPS(sub, sub, "c", I, "xer")
+
+#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, suffix, sign) \
+ ATOMIC_OP(op, asm_op, suffix, sign) \
+ ATOMIC_FETCH_OP_RELAXED(op, asm_op, suffix, sign)
+
+ATOMIC_OPS(and, and, ".", K)
+ATOMIC_OPS(or, or, "", K)
+ATOMIC_OPS(xor, xor, "", K)
+
+#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
+
+#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;
+ unsigned int eh = IS_ENABLED(CONFIG_PPC64);
+
+ __asm__ __volatile__ (
+"1: lwarx %0,0,%2,%[eh] # 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), [eh] "n" (eh)
+ : "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%I2c %0,%0,%2 \n"
+" stwcx. %0,0,%1 \n\
+ bne- 1b \n"
+ PPC_ATOMIC_EXIT_BARRIER
+" sub%I2c %0,%0,%2 \n\
+2:"
+ : "=&r" (t)
+ : "r" (&v->counter), "rI" (a), "r" (u)
+ : "cc", "memory", "xer");
+
+ return t;
+}
+#define arch_atomic_fetch_add_unless arch_atomic_fetch_add_unless
+
+/*
+ * 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<>"(v->counter));
+
+ return t;
+}
+
+static __inline__ void arch_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 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_ */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 22:03:09 +0000