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Diffstat (limited to 'kernel/arch/frv/include/asm/atomic.h')
-rw-r--r-- | kernel/arch/frv/include/asm/atomic.h | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/kernel/arch/frv/include/asm/atomic.h b/kernel/arch/frv/include/asm/atomic.h new file mode 100644 index 000000000..102190a61 --- /dev/null +++ b/kernel/arch/frv/include/asm/atomic.h @@ -0,0 +1,200 @@ +/* atomic.h: atomic operation emulation for FR-V + * + * For an explanation of how atomic ops work in this arch, see: + * Documentation/frv/atomic-ops.txt + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * 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; either version + * 2 of the License, or (at your option) any later version. + */ +#ifndef _ASM_ATOMIC_H +#define _ASM_ATOMIC_H + +#include <linux/types.h> +#include <asm/spr-regs.h> +#include <asm/cmpxchg.h> +#include <asm/barrier.h> + +#ifdef CONFIG_SMP +#error not SMP safe +#endif + +/* + * Atomic operations that C can't guarantee us. Useful for + * resource counting etc.. + * + * We do not have SMP systems, so we don't have to deal with that. + */ + +#define ATOMIC_INIT(i) { (i) } +#define atomic_read(v) ACCESS_ONCE((v)->counter) +#define atomic_set(v, i) (((v)->counter) = (i)) + +#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS +static inline int atomic_add_return(int i, atomic_t *v) +{ + unsigned long val; + + asm("0: \n" + " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */ + " ckeq icc3,cc7 \n" + " ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */ + " orcr cc7,cc7,cc3 \n" /* set CC3 to true */ + " add%I2 %1,%2,%1 \n" + " cst.p %1,%M0 ,cc3,#1 \n" + " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */ + " beq icc3,#0,0b \n" + : "+U"(v->counter), "=&r"(val) + : "NPr"(i) + : "memory", "cc7", "cc3", "icc3" + ); + + return val; +} + +static inline int atomic_sub_return(int i, atomic_t *v) +{ + unsigned long val; + + asm("0: \n" + " orcc gr0,gr0,gr0,icc3 \n" /* set ICC3.Z */ + " ckeq icc3,cc7 \n" + " ld.p %M0,%1 \n" /* LD.P/ORCR must be atomic */ + " orcr cc7,cc7,cc3 \n" /* set CC3 to true */ + " sub%I2 %1,%2,%1 \n" + " cst.p %1,%M0 ,cc3,#1 \n" + " corcc gr29,gr29,gr0 ,cc3,#1 \n" /* clear ICC3.Z if store happens */ + " beq icc3,#0,0b \n" + : "+U"(v->counter), "=&r"(val) + : "NPr"(i) + : "memory", "cc7", "cc3", "icc3" + ); + + return val; +} + +#else + +extern int atomic_add_return(int i, atomic_t *v); +extern int atomic_sub_return(int i, atomic_t *v); + +#endif + +static inline int atomic_add_negative(int i, atomic_t *v) +{ + return atomic_add_return(i, v) < 0; +} + +static inline void atomic_add(int i, atomic_t *v) +{ + atomic_add_return(i, v); +} + +static inline void atomic_sub(int i, atomic_t *v) +{ + atomic_sub_return(i, v); +} + +static inline void atomic_inc(atomic_t *v) +{ + atomic_add_return(1, v); +} + +static inline void atomic_dec(atomic_t *v) +{ + atomic_sub_return(1, v); +} + +#define atomic_dec_return(v) atomic_sub_return(1, (v)) +#define atomic_inc_return(v) atomic_add_return(1, (v)) + +#define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) +#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) +#define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) + +/* + * 64-bit atomic ops + */ +typedef struct { + volatile long long counter; +} atomic64_t; + +#define ATOMIC64_INIT(i) { (i) } + +static inline long long atomic64_read(atomic64_t *v) +{ + long long counter; + + asm("ldd%I1 %M1,%0" + : "=e"(counter) + : "m"(v->counter)); + return counter; +} + +static inline void atomic64_set(atomic64_t *v, long long i) +{ + asm volatile("std%I0 %1,%M0" + : "=m"(v->counter) + : "e"(i)); +} + +extern long long atomic64_inc_return(atomic64_t *v); +extern long long atomic64_dec_return(atomic64_t *v); +extern long long atomic64_add_return(long long i, atomic64_t *v); +extern long long atomic64_sub_return(long long i, atomic64_t *v); + +static inline long long atomic64_add_negative(long long i, atomic64_t *v) +{ + return atomic64_add_return(i, v) < 0; +} + +static inline void atomic64_add(long long i, atomic64_t *v) +{ + atomic64_add_return(i, v); +} + +static inline void atomic64_sub(long long i, atomic64_t *v) +{ + atomic64_sub_return(i, v); +} + +static inline void atomic64_inc(atomic64_t *v) +{ + atomic64_inc_return(v); +} + +static inline void atomic64_dec(atomic64_t *v) +{ + atomic64_dec_return(v); +} + +#define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0) +#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0) +#define atomic64_inc_and_test(v) (atomic64_inc_return((v)) == 0) + +#define atomic_cmpxchg(v, old, new) (cmpxchg(&(v)->counter, old, new)) +#define atomic_xchg(v, new) (xchg(&(v)->counter, new)) +#define atomic64_cmpxchg(v, old, new) (__cmpxchg_64(old, new, &(v)->counter)) +#define atomic64_xchg(v, new) (__xchg_64(new, &(v)->counter)) + +static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u) +{ + int c, old; + c = atomic_read(v); + for (;;) { + if (unlikely(c == (u))) + break; + old = atomic_cmpxchg((v), c, c + (a)); + if (likely(old == c)) + break; + c = old; + } + return c; +} + + +#endif /* _ASM_ATOMIC_H */ |