aboutsummaryrefslogtreecommitdiff
path: root/arch/sparc/lib/atomic_64.S
blob: d6b0363f345bfbd41aeb4a7a287ee651404f2259 (plain)
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
/* atomic.S: These things are too big to do inline.
 *
 * Copyright (C) 1999, 2007 2012 David S. Miller (davem@davemloft.net)
 */

#include <linux/linkage.h>
#include <asm/asi.h>
#include <asm/backoff.h>

	.text

	/* Two versions of the atomic routines, one that
	 * does not return a value and does not perform
	 * memory barriers, and a second which returns
	 * a value and does the barriers.
	 */

#define ATOMIC_OP(op)							\
ENTRY(atomic_##op) /* %o0 = increment, %o1 = atomic_ptr */		\
	BACKOFF_SETUP(%o2);						\
1:	lduw	[%o1], %g1;						\
	op	%g1, %o0, %g7;						\
	cas	[%o1], %g1, %g7;					\
	cmp	%g1, %g7;						\
	bne,pn	%icc, BACKOFF_LABEL(2f, 1b);				\
	 nop;								\
	retl;								\
	 nop;								\
2:	BACKOFF_SPIN(%o2, %o3, 1b);					\
ENDPROC(atomic_##op);							\

#define ATOMIC_OP_RETURN(op)						\
ENTRY(atomic_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */	\
	BACKOFF_SETUP(%o2);						\
1:	lduw	[%o1], %g1;						\
	op	%g1, %o0, %g7;						\
	cas	[%o1], %g1, %g7;					\
	cmp	%g1, %g7;						\
	bne,pn	%icc, BACKOFF_LABEL(2f, 1b);				\
	 op	%g1, %o0, %g1;						\
	retl;								\
	 sra	%g1, 0, %o0;						\
2:	BACKOFF_SPIN(%o2, %o3, 1b);					\
ENDPROC(atomic_##op##_return);

#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)

ATOMIC_OPS(add)
ATOMIC_OPS(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)

#undef ATOMIC_OPS
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

#define ATOMIC64_OP(op)							\
ENTRY(atomic64_##op) /* %o0 = increment, %o1 = atomic_ptr */		\
	BACKOFF_SETUP(%o2);						\
1:	ldx	[%o1], %g1;						\
	op	%g1, %o0, %g7;						\
	casx	[%o1], %g1, %g7;					\
	cmp	%g1, %g7;						\
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b);				\
	 nop;								\
	retl;								\
	 nop;								\
2:	BACKOFF_SPIN(%o2, %o3, 1b);					\
ENDPROC(atomic64_##op);							\

#define ATOMIC64_OP_RETURN(op)						\
ENTRY(atomic64_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */	\
	BACKOFF_SETUP(%o2);						\
1:	ldx	[%o1], %g1;						\
	op	%g1, %o0, %g7;						\
	casx	[%o1], %g1, %g7;					\
	cmp	%g1, %g7;						\
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b);				\
	 nop;								\
	retl;								\
	 op	%g1, %o0, %o0;						\
2:	BACKOFF_SPIN(%o2, %o3, 1b);					\
ENDPROC(atomic64_##op##_return);

#define ATOMIC64_OPS(op) ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op)

ATOMIC64_OPS(add)
ATOMIC64_OPS(sub)
ATOMIC64_OP(and)
ATOMIC64_OP(or)
ATOMIC64_OP(xor)

#undef ATOMIC64_OPS
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP

ENTRY(atomic64_dec_if_positive) /* %o0 = atomic_ptr */
	BACKOFF_SETUP(%o2)
1:	ldx	[%o0], %g1
	brlez,pn %g1, 3f
	 sub	%g1, 1, %g7
	casx	[%o0], %g1, %g7
	cmp	%g1, %g7
	bne,pn	%xcc, BACKOFF_LABEL(2f, 1b)
	 nop
3:	retl
	 sub	%g1, 1, %o0
2:	BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_dec_if_positive)