summaryrefslogtreecommitdiffstats
path: root/arch/sh/include/asm/bitops-op32.h
blob: 466880362ad1deef9240a194e0ae3fd3932c0daf (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
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
137
138
139
140
141
142
143
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_SH_BITOPS_OP32_H
#define __ASM_SH_BITOPS_OP32_H

/*
 * The bit modifying instructions on SH-2A are only capable of working
 * with a 3-bit immediate, which signifies the shift position for the bit
 * being worked on.
 */
#if defined(__BIG_ENDIAN)
#define BITOP_LE_SWIZZLE	((BITS_PER_LONG-1) & ~0x7)
#define BYTE_NUMBER(nr)		((nr ^ BITOP_LE_SWIZZLE) / BITS_PER_BYTE)
#define BYTE_OFFSET(nr)		((nr ^ BITOP_LE_SWIZZLE) % BITS_PER_BYTE)
#else
#define BYTE_NUMBER(nr)		((nr) / BITS_PER_BYTE)
#define BYTE_OFFSET(nr)		((nr) % BITS_PER_BYTE)
#endif

#define IS_IMMEDIATE(nr)	(__builtin_constant_p(nr))

static inline void __set_bit(int nr, volatile unsigned long *addr)
{
	if (IS_IMMEDIATE(nr)) {
		__asm__ __volatile__ (
			"bset.b %1, @(%O2,%0)		! __set_bit\n\t"
			: "+r" (addr)
			: "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr))
			: "t", "memory"
		);
	} else {
		unsigned long mask = BIT_MASK(nr);
		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

		*p |= mask;
	}
}

static inline void __clear_bit(int nr, volatile unsigned long *addr)
{
	if (IS_IMMEDIATE(nr)) {
		__asm__ __volatile__ (
			"bclr.b %1, @(%O2,%0)		! __clear_bit\n\t"
			: "+r" (addr)
			: "i" (BYTE_OFFSET(nr)),
			  "i" (BYTE_NUMBER(nr))
			: "t", "memory"
		);
	} else {
		unsigned long mask = BIT_MASK(nr);
		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

		*p &= ~mask;
	}
}

/**
 * __change_bit - Toggle a bit in memory
 * @nr: the bit to change
 * @addr: the address to start counting from
 *
 * Unlike change_bit(), this function is non-atomic and may be reordered.
 * If it's called on the same region of memory simultaneously, the effect
 * may be that only one operation succeeds.
 */
static inline void __change_bit(int nr, volatile unsigned long *addr)
{
	if (IS_IMMEDIATE(nr)) {
		__asm__ __volatile__ (
			"bxor.b %1, @(%O2,%0)		! __change_bit\n\t"
			: "+r" (addr)
			: "i" (BYTE_OFFSET(nr)),
			  "i" (BYTE_NUMBER(nr))
			: "t", "memory"
		);
	} else {
		unsigned long mask = BIT_MASK(nr);
		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);

		*p ^= mask;
	}
}

/**
 * __test_and_set_bit - Set a bit and return its old value
 * @nr: Bit to set
 * @addr: Address to count from
 *
 * This operation is non-atomic and can be reordered.
 * If two examples of this operation race, one can appear to succeed
 * but actually fail.  You must protect multiple accesses with a lock.
 */
static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	unsigned long old = *p;

	*p = old | mask;
	return (old & mask) != 0;
}

/**
 * __test_and_clear_bit - Clear a bit and return its old value
 * @nr: Bit to clear
 * @addr: Address to count from
 *
 * This operation is non-atomic and can be reordered.
 * If two examples of this operation race, one can appear to succeed
 * but actually fail.  You must protect multiple accesses with a lock.
 */
static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	unsigned long old = *p;

	*p = old & ~mask;
	return (old & mask) != 0;
}

/* WARNING: non atomic and it can be reordered! */
static inline int __test_and_change_bit(int nr,
					    volatile unsigned long *addr)
{
	unsigned long mask = BIT_MASK(nr);
	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
	unsigned long old = *p;

	*p = old ^ mask;
	return (old & mask) != 0;
}

/**
 * test_bit - Determine whether a bit is set
 * @nr: bit number to test
 * @addr: Address to start counting from
 */
static inline int test_bit(int nr, const volatile unsigned long *addr)
{
	return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}

#endif /* __ASM_SH_BITOPS_OP32_H */