1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ARCH_M68K_CMPXCHG__
#define __ARCH_M68K_CMPXCHG__
#include <linux/irqflags.h>
struct __xchg_dummy { unsigned long a[100]; };
#define __xg(x) ((volatile struct __xchg_dummy *)(x))
extern unsigned long __invalid_xchg_size(unsigned long, volatile void *, int);
#ifndef CONFIG_RMW_INSNS
static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
{
unsigned long flags, tmp;
local_irq_save(flags);
switch (size) {
case 1:
tmp = *(u8 *)ptr;
*(u8 *)ptr = x;
x = tmp;
break;
case 2:
tmp = *(u16 *)ptr;
*(u16 *)ptr = x;
x = tmp;
break;
case 4:
tmp = *(u32 *)ptr;
*(u32 *)ptr = x;
x = tmp;
break;
default:
tmp = __invalid_xchg_size(x, ptr, size);
break;
}
local_irq_restore(flags);
return x;
}
#else
static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
{
switch (size) {
case 1:
__asm__ __volatile__
("moveb %2,%0\n\t"
"1:\n\t"
"casb %0,%1,%2\n\t"
"jne 1b"
: "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory");
break;
case 2:
__asm__ __volatile__
("movew %2,%0\n\t"
"1:\n\t"
"casw %0,%1,%2\n\t"
"jne 1b"
: "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory");
break;
case 4:
__asm__ __volatile__
("movel %2,%0\n\t"
"1:\n\t"
"casl %0,%1,%2\n\t"
"jne 1b"
: "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory");
break;
default:
x = __invalid_xchg_size(x, ptr, size);
break;
}
return x;
}
#endif
#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
#include <asm-generic/cmpxchg-local.h>
#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
extern unsigned long __invalid_cmpxchg_size(volatile void *,
unsigned long, unsigned long, int);
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
#ifdef CONFIG_RMW_INSNS
static inline unsigned long __cmpxchg(volatile void *p, unsigned long old,
unsigned long new, int size)
{
switch (size) {
case 1:
__asm__ __volatile__ ("casb %0,%2,%1"
: "=d" (old), "=m" (*(char *)p)
: "d" (new), "0" (old), "m" (*(char *)p));
break;
case 2:
__asm__ __volatile__ ("casw %0,%2,%1"
: "=d" (old), "=m" (*(short *)p)
: "d" (new), "0" (old), "m" (*(short *)p));
break;
case 4:
__asm__ __volatile__ ("casl %0,%2,%1"
: "=d" (old), "=m" (*(int *)p)
: "d" (new), "0" (old), "m" (*(int *)p));
break;
default:
old = __invalid_cmpxchg_size(p, old, new, size);
break;
}
return old;
}
#define cmpxchg(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n))
#else
#include <asm-generic/cmpxchg.h>
#endif
#endif /* __ARCH_M68K_CMPXCHG__ */
|
