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 1:						\
31		__xchg__res = xchg_u8(__xchg_ptr, x);	\
32		break;					\
33	default:					\
34		__xchg_called_with_bad_pointer();	\
35		__xchg__res = x;			\
36		break;					\
37	}						\
38							\
39	__xchg__res;					\
40})
41
42#define xchg(ptr,x)	\
43	((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
44
45/* This function doesn't exist, so you'll get a linker error
46 * if something tries to do an invalid cmpxchg(). */
47extern void __cmpxchg_called_with_bad_pointer(void);
48
49static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
50		unsigned long new, int size)
51{
52	switch (size) {
53	case 4:
54		return __cmpxchg_u32(ptr, old, new);
55	}
56	__cmpxchg_called_with_bad_pointer();
57	return old;
58}
59
60#define cmpxchg(ptr,o,n)						 \
61  ({									 \
62     __typeof__(*(ptr)) _o_ = (o);					 \
63     __typeof__(*(ptr)) _n_ = (n);					 \
64     (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
65				    (unsigned long)_n_, sizeof(*(ptr))); \
66  })
67
68#endif /* __ASM_SH_CMPXCHG_H */
69