diff options
Diffstat (limited to 'arch/mn10300/include/asm/atomic.h')
| -rw-r--r-- | arch/mn10300/include/asm/atomic.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/arch/mn10300/include/asm/atomic.h b/arch/mn10300/include/asm/atomic.h new file mode 100644 index 000000000..5be655e83 --- /dev/null +++ b/arch/mn10300/include/asm/atomic.h @@ -0,0 +1,199 @@ +/* MN10300 Atomic counter operations + * + * Copyright (C) 2007 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 Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#ifndef _ASM_ATOMIC_H +#define _ASM_ATOMIC_H + +#include <asm/irqflags.h> +#include <asm/cmpxchg.h> +#include <asm/barrier.h> + +#ifndef CONFIG_SMP +#include <asm-generic/atomic.h> +#else + +/* + * Atomic operations that C can't guarantee us. Useful for + * resource counting etc.. + */ + +#define ATOMIC_INIT(i) { (i) } + +#ifdef __KERNEL__ + +/** + * atomic_read - read atomic variable + * @v: pointer of type atomic_t + * + * Atomically reads the value of @v. Note that the guaranteed + */ +#define atomic_read(v) (ACCESS_ONCE((v)->counter)) + +/** + * atomic_set - set atomic variable + * @v: pointer of type atomic_t + * @i: required value + * + * Atomically sets the value of @v to @i. Note that the guaranteed + */ +#define atomic_set(v, i) (((v)->counter) = (i)) + +#define ATOMIC_OP(op) \ +static inline void atomic_##op(int i, atomic_t *v) \ +{ \ + int retval, status; \ + \ + asm volatile( \ + "1: mov %4,(_AAR,%3) \n" \ + " mov (_ADR,%3),%1 \n" \ + " " #op " %5,%1 \n" \ + " mov %1,(_ADR,%3) \n" \ + " mov (_ADR,%3),%0 \n" /* flush */ \ + " mov (_ASR,%3),%0 \n" \ + " or %0,%0 \n" \ + " bne 1b \n" \ + : "=&r"(status), "=&r"(retval), "=m"(v->counter) \ + : "a"(ATOMIC_OPS_BASE_ADDR), "r"(&v->counter), "r"(i) \ + : "memory", "cc"); \ +} + +#define ATOMIC_OP_RETURN(op) \ +static inline int atomic_##op##_return(int i, atomic_t *v) \ +{ \ + int retval, status; \ + \ + asm volatile( \ + "1: mov %4,(_AAR,%3) \n" \ + " mov (_ADR,%3),%1 \n" \ + " " #op " %5,%1 \n" \ + " mov %1,(_ADR,%3) \n" \ + " mov (_ADR,%3),%0 \n" /* flush */ \ + " mov (_ASR,%3),%0 \n" \ + " or %0,%0 \n" \ + " bne 1b \n" \ + : "=&r"(status), "=&r"(retval), "=m"(v->counter) \ + : "a"(ATOMIC_OPS_BASE_ADDR), "r"(&v->counter), "r"(i) \ + : "memory", "cc"); \ + return retval; \ +} + +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) + +ATOMIC_OPS(add) +ATOMIC_OPS(sub) + +#undef ATOMIC_OPS +#undef ATOMIC_OP_RETURN +#undef ATOMIC_OP + +static inline int atomic_add_negative(int i, atomic_t *v) +{ + return atomic_add_return(i, v) < 0; +} + +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) + +#define __atomic_add_unless(v, a, u) \ +({ \ + int c, old; \ + c = atomic_read(v); \ + while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \ + c = old; \ + c; \ +}) + +#define atomic_xchg(ptr, v) (xchg(&(ptr)->counter, (v))) +#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new))) + +/** + * atomic_clear_mask - Atomically clear bits in memory + * @mask: Mask of the bits to be cleared + * @v: pointer to word in memory + * + * Atomically clears the bits set in mask from the memory word specified. + */ +static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr) +{ +#ifdef CONFIG_SMP + int status; + + asm volatile( + "1: mov %3,(_AAR,%2) \n" + " mov (_ADR,%2),%0 \n" + " and %4,%0 \n" + " mov %0,(_ADR,%2) \n" + " mov (_ADR,%2),%0 \n" /* flush */ + " mov (_ASR,%2),%0 \n" + " or %0,%0 \n" + " bne 1b \n" + : "=&r"(status), "=m"(*addr) + : "a"(ATOMIC_OPS_BASE_ADDR), "r"(addr), "r"(~mask) + : "memory", "cc"); +#else + unsigned long flags; + + mask = ~mask; + flags = arch_local_cli_save(); + *addr &= mask; + arch_local_irq_restore(flags); +#endif +} + +/** + * atomic_set_mask - Atomically set bits in memory + * @mask: Mask of the bits to be set + * @v: pointer to word in memory + * + * Atomically sets the bits set in mask from the memory word specified. + */ +static inline void atomic_set_mask(unsigned long mask, unsigned long *addr) +{ +#ifdef CONFIG_SMP + int status; + + asm volatile( + "1: mov %3,(_AAR,%2) \n" + " mov (_ADR,%2),%0 \n" + " or %4,%0 \n" + " mov %0,(_ADR,%2) \n" + " mov (_ADR,%2),%0 \n" /* flush */ + " mov (_ASR,%2),%0 \n" + " or %0,%0 \n" + " bne 1b \n" + : "=&r"(status), "=m"(*addr) + : "a"(ATOMIC_OPS_BASE_ADDR), "r"(addr), "r"(mask) + : "memory", "cc"); +#else + unsigned long flags; + + flags = arch_local_cli_save(); + *addr |= mask; + arch_local_irq_restore(flags); +#endif +} + +#endif /* __KERNEL__ */ +#endif /* CONFIG_SMP */ +#endif /* _ASM_ATOMIC_H */ |