xref: /linux/arch/sh/include/asm/cmpxchg.h (revision 8e1bb4a41aa78d6105e59186af3dcd545fc66e70)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_CMPXCHG_H
3 #define __ASM_SH_CMPXCHG_H
4 
5 /*
6  * Atomic operations that C can't guarantee us.  Useful for
7  * resource counting etc..
8  */
9 
10 #include <linux/compiler.h>
11 #include <linux/types.h>
12 
13 #if defined(CONFIG_GUSA_RB)
14 #include <asm/cmpxchg-grb.h>
15 #elif defined(CONFIG_CPU_SH4A)
16 #include <asm/cmpxchg-llsc.h>
17 #elif defined(CONFIG_CPU_J2) && defined(CONFIG_SMP)
18 #include <asm/cmpxchg-cas.h>
19 #else
20 #include <asm/cmpxchg-irq.h>
21 #endif
22 
23 extern void __xchg_called_with_bad_pointer(void);
24 
25 #define __arch_xchg(ptr, x, size)				\
26 ({							\
27 	unsigned long __xchg__res;			\
28 	volatile void *__xchg_ptr = (ptr);		\
29 	switch (size) {					\
30 	case 4:						\
31 		__xchg__res = xchg_u32(__xchg_ptr, x);	\
32 		break;					\
33 	case 2:						\
34 		__xchg__res = xchg_u16(__xchg_ptr, x);	\
35 		break;					\
36 	case 1:						\
37 		__xchg__res = xchg_u8(__xchg_ptr, x);	\
38 		break;					\
39 	default:					\
40 		__xchg_called_with_bad_pointer();	\
41 		__xchg__res = x;			\
42 		break;					\
43 	}						\
44 							\
45 	__xchg__res;					\
46 })
47 
48 #define arch_xchg(ptr,x)	\
49 	((__typeof__(*(ptr)))__arch_xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
50 
51 /* This function doesn't exist, so you'll get a linker error
52  * if something tries to do an invalid cmpxchg(). */
53 extern void __cmpxchg_called_with_bad_pointer(void);
54 
55 static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
56 		unsigned long new, int size)
57 {
58 	switch (size) {
59 	case 4:
60 		return __cmpxchg_u32(ptr, old, new);
61 	}
62 	__cmpxchg_called_with_bad_pointer();
63 	return old;
64 }
65 
66 #define arch_cmpxchg(ptr,o,n)						 \
67   ({									 \
68      __typeof__(*(ptr)) _o_ = (o);					 \
69      __typeof__(*(ptr)) _n_ = (n);					 \
70      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
71 				    (unsigned long)_n_, sizeof(*(ptr))); \
72   })
73 
74 #include <asm-generic/cmpxchg-local.h>
75 
76 #define arch_cmpxchg_local(ptr, o, n) ({				\
77 	(__typeof__(*ptr))__generic_cmpxchg_local((ptr),		\
78 						  (unsigned long)(o),	\
79 						  (unsigned long)(n),	\
80 						  sizeof(*(ptr)));	\
81 })
82 
83 #endif /* __ASM_SH_CMPXCHG_H */
84