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-rw-r--r--src/target/firmware/include/asm/atomic.h106
1 files changed, 106 insertions, 0 deletions
diff --git a/src/target/firmware/include/asm/atomic.h b/src/target/firmware/include/asm/atomic.h
new file mode 100644
index 00000000..19e8ce6f
--- /dev/null
+++ b/src/target/firmware/include/asm/atomic.h
@@ -0,0 +1,106 @@
+/*
+ * linux/include/asm-arm/atomic.h
+ *
+ * Copyright (C) 1996 Russell King.
+ * Copyright (C) 2002 Deep Blue Solutions Ltd.
+ *
+ * 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.
+ */
+#ifndef __ASM_ARM_ATOMIC_H
+#define __ASM_ARM_ATOMIC_H
+
+typedef struct { volatile int counter; } atomic_t;
+
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_read(v) ((v)->counter)
+
+#include <asm/system.h>
+#include <asm/compiler.h>
+
+#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 int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ int ret;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ ret = v->counter;
+ if (likely(ret == old))
+ v->counter = new;
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+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_xchg(v, new) (xchg(&((v)->counter), new))
+
+static inline int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int c, old;
+
+ c = atomic_read(v);
+ while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+#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_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
+
+#define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0)
+
+/* Atomic operations are already serializing on ARM */
+#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