1 files changed, 148 insertions, 0 deletions

diff --git a/include/asm-m68k/atomic.h b/include/asm-m68k/atomic.h
new file mode 100644
index 000000000000..38f3043e7fe1
--- /dev/null
+++ b/include/asm-m68k/atomic.h
@@ -0,0 +1,148 @@
+#ifndef __ARCH_M68K_ATOMIC__
+#define __ARCH_M68K_ATOMIC__
+
+#include <linux/config.h>
+
+#include <asm/system.h> /* local_irq_XXX() */
+
+/*
+ * 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.
+ */
+
+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)
+{
+        __asm__ __volatile__("addl %1,%0" : "+m" (*v) : "id" (i));
+}
+
+static inline void atomic_sub(int i, atomic_t *v)
+{
+        __asm__ __volatile__("subl %1,%0" : "+m" (*v) : "id" (i));
+}
+
+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_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
+static inline int atomic_add_return(int i, atomic_t *v)
+{
+        int t, tmp;
+
+        __asm__ __volatile__(
+                        "1:     movel %2,%1\n"
+                        "       addl %3,%1\n"
+                        "       casl %2,%1,%0\n"
+                        "       jne 1b"
+                        : "+m" (*v), "=&d" (t), "=&d" (tmp)
+                        : "g" (i), "2" (atomic_read(v)));
+        return t;
+}
+
+static inline int atomic_sub_return(int i, atomic_t *v)
+{
+        int t, tmp;
+
+        __asm__ __volatile__(
+                        "1:     movel %2,%1\n"
+                        "       subl %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 /* !CONFIG_RMW_INSNS */
+static inline int atomic_add_return(int i, atomic_t * v)
+{
+        unsigned long flags;
+        int t;
+
+        local_irq_save(flags);
+        t = atomic_read(v);
+        t += i;
+        atomic_set(v, t);
+        local_irq_restore(flags);
+
+        return t;
+}
+
+static inline int atomic_sub_return(int i, atomic_t * v)
+{
+        unsigned long flags;
+        int t;
+
+        local_irq_save(flags);
+        t = atomic_read(v);
+        t -= i;
+        atomic_set(v, t);
+        local_irq_restore(flags);
+
+        return t;
+}
+#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): "g" (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): "g" (i));
+        return c != 0;
+}
+
+static inline void atomic_clear_mask(unsigned long mask, unsigned long *v)
+{
+        __asm__ __volatile__("andl %1,%0" : "+m" (*v) : "id" (~(mask)));
+}
+
+static inline void atomic_set_mask(unsigned long mask, unsigned long *v)
+{
+        __asm__ __volatile__("orl %1,%0" : "+m" (*v) : "id" (mask));
+}
+
+/* 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()
+
+#endif /* __ARCH_M68K_ATOMIC __ */