xref: /OK3568_Linux_fs/kernel/arch/sh/include/asm/cmpxchg.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef __ASM_SH_CMPXCHG_H
3*4882a593Smuzhiyun #define __ASM_SH_CMPXCHG_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun /*
6*4882a593Smuzhiyun  * Atomic operations that C can't guarantee us.  Useful for
7*4882a593Smuzhiyun  * resource counting etc..
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <linux/compiler.h>
11*4882a593Smuzhiyun #include <linux/types.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #if defined(CONFIG_GUSA_RB)
14*4882a593Smuzhiyun #include <asm/cmpxchg-grb.h>
15*4882a593Smuzhiyun #elif defined(CONFIG_CPU_SH4A)
16*4882a593Smuzhiyun #include <asm/cmpxchg-llsc.h>
17*4882a593Smuzhiyun #elif defined(CONFIG_CPU_J2) && defined(CONFIG_SMP)
18*4882a593Smuzhiyun #include <asm/cmpxchg-cas.h>
19*4882a593Smuzhiyun #else
20*4882a593Smuzhiyun #include <asm/cmpxchg-irq.h>
21*4882a593Smuzhiyun #endif
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun extern void __xchg_called_with_bad_pointer(void);
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun #define __xchg(ptr, x, size)				\
26*4882a593Smuzhiyun ({							\
27*4882a593Smuzhiyun 	unsigned long __xchg__res;			\
28*4882a593Smuzhiyun 	volatile void *__xchg_ptr = (ptr);		\
29*4882a593Smuzhiyun 	switch (size) {					\
30*4882a593Smuzhiyun 	case 4:						\
31*4882a593Smuzhiyun 		__xchg__res = xchg_u32(__xchg_ptr, x);	\
32*4882a593Smuzhiyun 		break;					\
33*4882a593Smuzhiyun 	case 2:						\
34*4882a593Smuzhiyun 		__xchg__res = xchg_u16(__xchg_ptr, x);	\
35*4882a593Smuzhiyun 		break;					\
36*4882a593Smuzhiyun 	case 1:						\
37*4882a593Smuzhiyun 		__xchg__res = xchg_u8(__xchg_ptr, x);	\
38*4882a593Smuzhiyun 		break;					\
39*4882a593Smuzhiyun 	default:					\
40*4882a593Smuzhiyun 		__xchg_called_with_bad_pointer();	\
41*4882a593Smuzhiyun 		__xchg__res = x;			\
42*4882a593Smuzhiyun 		break;					\
43*4882a593Smuzhiyun 	}						\
44*4882a593Smuzhiyun 							\
45*4882a593Smuzhiyun 	__xchg__res;					\
46*4882a593Smuzhiyun })
47*4882a593Smuzhiyun 
48*4882a593Smuzhiyun #define xchg(ptr,x)	\
49*4882a593Smuzhiyun 	((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
50*4882a593Smuzhiyun 
51*4882a593Smuzhiyun /* This function doesn't exist, so you'll get a linker error
52*4882a593Smuzhiyun  * if something tries to do an invalid cmpxchg(). */
53*4882a593Smuzhiyun extern void __cmpxchg_called_with_bad_pointer(void);
54*4882a593Smuzhiyun 
__cmpxchg(volatile void * ptr,unsigned long old,unsigned long new,int size)55*4882a593Smuzhiyun static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
56*4882a593Smuzhiyun 		unsigned long new, int size)
57*4882a593Smuzhiyun {
58*4882a593Smuzhiyun 	switch (size) {
59*4882a593Smuzhiyun 	case 4:
60*4882a593Smuzhiyun 		return __cmpxchg_u32(ptr, old, new);
61*4882a593Smuzhiyun 	}
62*4882a593Smuzhiyun 	__cmpxchg_called_with_bad_pointer();
63*4882a593Smuzhiyun 	return old;
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun #define cmpxchg(ptr,o,n)						 \
67*4882a593Smuzhiyun   ({									 \
68*4882a593Smuzhiyun      __typeof__(*(ptr)) _o_ = (o);					 \
69*4882a593Smuzhiyun      __typeof__(*(ptr)) _n_ = (n);					 \
70*4882a593Smuzhiyun      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
71*4882a593Smuzhiyun 				    (unsigned long)_n_, sizeof(*(ptr))); \
72*4882a593Smuzhiyun   })
73*4882a593Smuzhiyun 
74*4882a593Smuzhiyun #endif /* __ASM_SH_CMPXCHG_H */
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