1#ifndef __ASM_SH_CMPXCHG_H
 2#define __ASM_SH_CMPXCHG_H
 3
 4/*
 5 * Atomic operations that C can't guarantee us.  Useful for
 6 * resource counting etc..
 7 */
 8
 9#include <linux/compiler.h>
10#include <linux/types.h>
11
12#if defined(CONFIG_GUSA_RB)
13#include <asm/cmpxchg-grb.h>
14#elif defined(CONFIG_CPU_SH4A)
15#include <asm/cmpxchg-llsc.h>
16#else
17#include <asm/cmpxchg-irq.h>
18#endif
19
20extern void __xchg_called_with_bad_pointer(void);
21
22#define __xchg(ptr, x, size)				\
23({							\
24	unsigned long __xchg__res;			\
25	volatile void *__xchg_ptr = (ptr);		\
26	switch (size) {					\
27	case 4:						\
28		__xchg__res = xchg_u32(__xchg_ptr, x);	\
29		break;					\
30	case 2:						\
31		__xchg__res = xchg_u16(__xchg_ptr, x);	\
32		break;					\
33	case 1:						\
34		__xchg__res = xchg_u8(__xchg_ptr, x);	\
35		break;					\
36	default:					\
37		__xchg_called_with_bad_pointer();	\
38		__xchg__res = x;			\
39		break;					\
40	}						\
41							\
42	__xchg__res;					\
43})
44
45#define xchg(ptr,x)	\
46	((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
47
48/* This function doesn't exist, so you'll get a linker error
49 * if something tries to do an invalid cmpxchg(). */
50extern void __cmpxchg_called_with_bad_pointer(void);
51
52static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
53		unsigned long new, int size)
54{
55	switch (size) {
56	case 4:
57		return __cmpxchg_u32(ptr, old, new);
58	}
59	__cmpxchg_called_with_bad_pointer();
60	return old;
61}
62
63#define cmpxchg(ptr,o,n)						 \
64  ({									 \
65     __typeof__(*(ptr)) _o_ = (o);					 \
66     __typeof__(*(ptr)) _n_ = (n);					 \
67     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
68				    (unsigned long)_n_, sizeof(*(ptr))); \
69  })
70
71#endif /* __ASM_SH_CMPXCHG_H */