Initial import

1 files changed, 198 insertions, 0 deletions

diff --git a/arch/m68k/include/asm/atomic.h b/arch/m68k/include/asm/atomic.h
new file mode 100644
index 000000000..e85f047fb
--- /dev/null
+++ b/arch/m68k/include/asm/atomic.h
@@ -0,0 +1,198 @@
+#ifndef __ARCH_M68K_ATOMIC__
+#define __ARCH_M68K_ATOMIC__
+
+#include <linux/types.h>
+#include <linux/irqflags.h>
+#include <asm/cmpxchg.h>
+#include <asm/barrier.h>
+
+/*
+ * Atomic operations that C can't guarantee us.  Useful for
+ * resource counting etc..
+ */
+
+/*
+ * We do not have SMP m68k 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)
+
+/*
+ * The ColdFire parts cannot do some immediate to memory operations,
+ * so for them we do not specify the "i" asm constraint.
+ */
+#ifdef CONFIG_COLDFIRE
+#define	ASM_DI	"d"
+#else
+#define	ASM_DI	"di"
+#endif
+
+#define ATOMIC_OP(op, c_op, asm_op)					\
+static inline void atomic_##op(int i, atomic_t *v)			\
+{									\
+	__asm__ __volatile__(#asm_op "l %1,%0" : "+m" (*v) : ASM_DI (i));\
+}									\
+
+#ifdef CONFIG_RMW_INSNS
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op)				\
+static inline int atomic_##op##_return(int i, atomic_t *v)		\
+{									\
+	int t, tmp;							\
+									\
+	__asm__ __volatile__(						\
+			"1:	movel %2,%1\n"				\
+			"	" #asm_op "l %3,%1\n"			\
+			"	casl %2,%1,%0\n"			\
+			"	jne 1b"					\
+			: "+m" (*v), "=&d" (t), "=&d" (tmp)		\
+			: "g" (i), "2" (atomic_read(v)));		\
+	return t;							\
+}
+
+#else
+
+#define ATOMIC_OP_RETURN(op, c_op, asm_op)				\
+static inline int atomic_##op##_return(int i, atomic_t * v)		\
+{									\
+	unsigned long flags;						\
+	int t;								\
+									\
+	local_irq_save(flags);						\
+	t = (v->counter c_op i);					\
+	local_irq_restore(flags);					\
+									\
+	return t;							\
+}
+
+#endif /* CONFIG_RMW_INSNS */
+
+#define ATOMIC_OPS(op, c_op, asm_op)					\
+	ATOMIC_OP(op, c_op, asm_op)					\
+	ATOMIC_OP_RETURN(op, c_op, asm_op)
+
+ATOMIC_OPS(add, +=, add)
+ATOMIC_OPS(sub, -=, sub)
+
+#undef ATOMIC_OPS
+#undef ATOMIC_OP_RETURN
+#undef ATOMIC_OP
+
+static inline void atomic_inc(atomic_t *v)
+{
+	__asm__ __volatile__("addql #1,%0" : "+m" (*v));
+}
+
+static inline void atomic_dec(atomic_t *v)
+{
+	__asm__ __volatile__("subql #1,%0" : "+m" (*v));
+}
+
+static inline int atomic_dec_and_test(atomic_t *v)
+{
+	char c;
+	__asm__ __volatile__("subql #1,%1; seq %0" : "=d" (c), "+m" (*v));
+	return c != 0;
+}
+
+static inline int atomic_dec_and_test_lt(atomic_t *v)
+{
+	char c;
+	__asm__ __volatile__(
+		"subql #1,%1; slt %0"
+		: "=d" (c), "=m" (*v)
+		: "m" (*v));
+	return c != 0;
+}
+
+static inline int atomic_inc_and_test(atomic_t *v)
+{
+	char c;
+	__asm__ __volatile__("addql #1,%1; seq %0" : "=d" (c), "+m" (*v));
+	return c != 0;
+}
+
+#ifdef CONFIG_RMW_INSNS
+
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+#else /* !CONFIG_RMW_INSNS */
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+	unsigned long flags;
+	int prev;
+
+	local_irq_save(flags);
+	prev = atomic_read(v);
+	if (prev == old)
+		atomic_set(v, new);
+	local_irq_restore(flags);
+	return prev;
+}
+
+static inline int atomic_xchg(atomic_t *v, int new)
+{
+	unsigned long flags;
+	int prev;
+
+	local_irq_save(flags);
+	prev = atomic_read(v);
+	atomic_set(v, new);
+	local_irq_restore(flags);
+	return prev;
+}
+
+#endif /* !CONFIG_RMW_INSNS */
+
+#define atomic_dec_return(v)	atomic_sub_return(1, (v))
+#define atomic_inc_return(v)	atomic_add_return(1, (v))
+
+static inline int atomic_sub_and_test(int i, atomic_t *v)
+{
+	char c;
+	__asm__ __volatile__("subl %2,%1; seq %0"
+			     : "=d" (c), "+m" (*v)
+			     : ASM_DI (i));
+	return c != 0;
+}
+
+static inline int atomic_add_negative(int i, atomic_t *v)
+{
+	char c;
+	__asm__ __volatile__("addl %2,%1; smi %0"
+			     : "=d" (c), "+m" (*v)
+			     : ASM_DI (i));
+	return c != 0;
+}
+
+static inline void atomic_clear_mask(unsigned long mask, unsigned long *v)
+{
+	__asm__ __volatile__("andl %1,%0" : "+m" (*v) : ASM_DI (~(mask)));
+}
+
+static inline void atomic_set_mask(unsigned long mask, unsigned long *v)
+{
+	__asm__ __volatile__("orl %1,%0" : "+m" (*v) : ASM_DI (mask));
+}
+
+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 /* __ARCH_M68K_ATOMIC __ */