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-rw-r--r--include/asm-arm26/atomic.h93
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diff --git a/include/asm-arm26/atomic.h b/include/asm-arm26/atomic.h
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+/*
+ * linux/include/asm-arm26/atomic.h
+ *
+ * Copyright (c) 1996 Russell King.
+ * Modified for arm26 by Ian Molton
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Changelog:
+ * 25-11-2004 IM Updated for 2.6.9
+ * 27-06-1996 RMK Created
+ * 13-04-1997 RMK Made functions atomic!
+ * 07-12-1997 RMK Upgraded for v2.1.
+ * 26-08-1998 PJB Added #ifdef __KERNEL__
+ *
+ * FIXME - its probably worth seeing what these compile into...
+ */
+#ifndef __ASM_ARM_ATOMIC_H
+#define __ASM_ARM_ATOMIC_H
+
+#include <linux/config.h>
+
+#ifdef CONFIG_SMP
+#error SMP is NOT supported
+#endif
+
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { (i) }
+
+#ifdef __KERNEL__
+#include <asm/system.h>
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v,i) (((v)->counter) = (i))
+
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+ unsigned long flags;
+ int val;
+
+ local_irq_save(flags);
+ val = v->counter;
+ v->counter = val += i;
+ local_irq_restore(flags);
+
+ return val;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+ unsigned long flags;
+ int val;
+
+ local_irq_save(flags);
+ val = v->counter;
+ v->counter = val -= i;
+ local_irq_restore(flags);
+
+ return val;
+}
+
+static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ *addr &= ~mask;
+ local_irq_restore(flags);
+}
+
+#define atomic_add(i, v) (void) atomic_add_return(i, v)
+#define atomic_inc(v) (void) atomic_add_return(1, v)
+#define atomic_sub(i, v) (void) atomic_sub_return(i, v)
+#define atomic_dec(v) (void) atomic_sub_return(1, v)
+
+#define atomic_inc_and_test(v) (atomic_add_return(1, v) == 0)
+#define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
+#define atomic_inc_return(v) (atomic_add_return(1, v))
+#define atomic_dec_return(v) (atomic_sub_return(1, v))
+
+#define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0)
+
+/* Atomic operations are already serializing on ARM26 */
+#define smp_mb__before_atomic_dec() barrier()
+#define smp_mb__after_atomic_dec() barrier()
+#define smp_mb__before_atomic_inc() barrier()
+#define smp_mb__after_atomic_inc() barrier()
+
+#endif
+#endif