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authorIngo Molnar <mingo@elte.hu>2008-09-10 11:32:52 +0200
committerIngo Molnar <mingo@elte.hu>2008-09-10 11:32:52 +0200
commite92b4fdacc6a7d8cc7895b81347671d5fcd6c5e1 (patch)
tree4f84567261682d8ec2ad4102bce1ff970a6eed1a /arch/blackfin/include/asm/atomic.h
parent9fcaff0e660d886e9a766460adbe558dd25de31b (diff)
parentadee14b2e1557d0a8559f29681732d05a89dfc35 (diff)
Merge commit 'v2.6.27-rc6' into x86/iommu
Diffstat (limited to 'arch/blackfin/include/asm/atomic.h')
-rw-r--r--arch/blackfin/include/asm/atomic.h144
1 files changed, 144 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/atomic.h b/arch/blackfin/include/asm/atomic.h
new file mode 100644
index 00000000000..7cf50871860
--- /dev/null
+++ b/arch/blackfin/include/asm/atomic.h
@@ -0,0 +1,144 @@
+#ifndef __ARCH_BLACKFIN_ATOMIC__
+#define __ARCH_BLACKFIN_ATOMIC__
+
+#include <asm/system.h> /* local_irq_XXX() */
+
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc..
+ *
+ * Generally we do not concern about SMP BFIN systems, so we don't have
+ * to deal with that.
+ *
+ * Tony Kou (tonyko@lineo.ca) Lineo Inc. 2001
+ */
+
+typedef struct {
+ int counter;
+} atomic_t;
+#define ATOMIC_INIT(i) { (i) }
+
+#define atomic_read(v) ((v)->counter)
+#define atomic_set(v, i) (((v)->counter) = i)
+
+static __inline__ void atomic_add(int i, atomic_t * v)
+{
+ long flags;
+
+ local_irq_save(flags);
+ v->counter += i;
+ local_irq_restore(flags);
+}
+
+static __inline__ void atomic_sub(int i, atomic_t * v)
+{
+ long flags;
+
+ local_irq_save(flags);
+ v->counter -= i;
+ local_irq_restore(flags);
+
+}
+
+static inline int atomic_add_return(int i, atomic_t * v)
+{
+ int __temp = 0;
+ long flags;
+
+ local_irq_save(flags);
+ v->counter += i;
+ __temp = v->counter;
+ local_irq_restore(flags);
+
+
+ return __temp;
+}
+
+#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
+static inline int atomic_sub_return(int i, atomic_t * v)
+{
+ int __temp = 0;
+ long flags;
+
+ local_irq_save(flags);
+ v->counter -= i;
+ __temp = v->counter;
+ local_irq_restore(flags);
+
+ return __temp;
+}
+
+static __inline__ void atomic_inc(volatile atomic_t * v)
+{
+ long flags;
+
+ local_irq_save(flags);
+ v->counter++;
+ local_irq_restore(flags);
+}
+
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+#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 != (u); \
+})
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+static __inline__ void atomic_dec(volatile atomic_t * v)
+{
+ long flags;
+
+ local_irq_save(flags);
+ v->counter--;
+ local_irq_restore(flags);
+}
+
+static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t * v)
+{
+ long flags;
+
+ local_irq_save(flags);
+ v->counter &= ~mask;
+ local_irq_restore(flags);
+}
+
+static __inline__ void atomic_set_mask(unsigned int mask, atomic_t * v)
+{
+ long flags;
+
+ local_irq_save(flags);
+ v->counter |= mask;
+ local_irq_restore(flags);
+}
+
+/* Atomic operations are already serializing */
+#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()
+
+#define atomic_dec_return(v) atomic_sub_return(1,(v))
+#define atomic_inc_return(v) atomic_add_return(1,(v))
+
+/*
+ * atomic_inc_and_test - increment and test
+ * @v: pointer of type atomic_t
+ *
+ * Atomically increments @v by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
+
+#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)
+
+#include <asm-generic/atomic.h>
+
+#endif /* __ARCH_BLACKFIN_ATOMIC __ */