sparc32: Add cmpxchg64().

This fixes the build with i40e driver enabled.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/include/asm/cmpxchg_32.h

@@ -62,6 +62,9 @@ __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size)
 			(unsigned long)_n_, sizeof(*(ptr)));		\
 })
 
+u64 __cmpxchg_u64(u64 *ptr, u64 old, u64 new);
+#define cmpxchg64(ptr, old, new)	__cmpxchg_u64(ptr, old, new)
+
 #include <asm-generic/cmpxchg-local.h>
 
 /*

arch/sparc/lib/atomic32.c

@@ -172,6 +172,20 @@ unsigned long __cmpxchg_u32(volatile u32 *ptr, u32 old, u32 new)
 }
 EXPORT_SYMBOL(__cmpxchg_u32);
 
+u64 __cmpxchg_u64(u64 *ptr, u64 old, u64 new)
+{
+	unsigned long flags;
+	u64 prev;
+
+	spin_lock_irqsave(ATOMIC_HASH(ptr), flags);
+	if ((prev = *ptr) == old)
+		*ptr = new;
+	spin_unlock_irqrestore(ATOMIC_HASH(ptr), flags);
+
+	return prev;
+}
+EXPORT_SYMBOL(__cmpxchg_u64);
+
 unsigned long __xchg_u32(volatile u32 *ptr, u32 new)
 {
 	unsigned long flags;