MN10300: Implement atomic ops using atomic ops unit

Implement atomic ops using the atomic ops unit available in the AM34 CPU.  This
allows the equivalent of the LL/SC instructions to be found on other CPUs.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 1 insertions, 47 deletions

diff --git a/arch/mn10300/include/asm/system.h b/arch/mn10300/include/asm/system.h
index 3c272a1a1015..7de90bc4cf80 100644
--- a/arch/mn10300/include/asm/system.h
+++ b/arch/mn10300/include/asm/system.h
@@ -18,6 +18,7 @@
 
 #include <linux/kernel.h>
 #include <linux/irqflags.h>
+#include <asm/atomic.h>
 
 #if !defined(CONFIG_LAZY_SAVE_FPU)
 struct fpu_state_struct;
@@ -96,52 +97,5 @@ do {									\
 #define read_barrier_depends()		do {} while (0)
 #define smp_read_barrier_depends()	do {} while (0)
 
-/*****************************************************************************/
-/*
- * MN10300 doesn't actually have an exchange instruction
- */
-#ifndef __ASSEMBLY__
-
-struct __xchg_dummy { unsigned long a[100]; };
-#define __xg(x) ((struct __xchg_dummy *)(x))
-
-static inline
-unsigned long __xchg(volatile unsigned long *m, unsigned long val)
-{
-	unsigned long retval;
-	unsigned long flags;
-
-	local_irq_save(flags);
-	retval = *m;
-	*m = val;
-	local_irq_restore(flags);
-	return retval;
-}
-
-#define xchg(ptr, v)						\
-	((__typeof__(*(ptr))) __xchg((unsigned long *)(ptr),	\
-				     (unsigned long)(v)))
-
-static inline unsigned long __cmpxchg(volatile unsigned long *m,
-				      unsigned long old, unsigned long new)
-{
-	unsigned long retval;
-	unsigned long flags;
-
-	local_irq_save(flags);
-	retval = *m;
-	if (retval == old)
-		*m = new;
-	local_irq_restore(flags);
-	return retval;
-}
-
-#define cmpxchg(ptr, o, n)					\
-	((__typeof__(*(ptr))) __cmpxchg((unsigned long *)(ptr), \
-					(unsigned long)(o),	\
-					(unsigned long)(n)))
-
-#endif /* !__ASSEMBLY__ */
-
 #endif /* __KERNEL__ */
 #endif /* _ASM_SYSTEM_H */