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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __ASM_SH_BITOPS_OP32_H
3#define __ASM_SH_BITOPS_OP32_H
4
5/*
6 * The bit modifying instructions on SH-2A are only capable of working
7 * with a 3-bit immediate, which signifies the shift position for the bit
8 * being worked on.
9 */
10#if defined(__BIG_ENDIAN)
11#define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7)
12#define BYTE_NUMBER(nr) ((nr ^ BITOP_LE_SWIZZLE) / BITS_PER_BYTE)
13#define BYTE_OFFSET(nr) ((nr ^ BITOP_LE_SWIZZLE) % BITS_PER_BYTE)
14#else
15#define BYTE_NUMBER(nr) ((nr) / BITS_PER_BYTE)
16#define BYTE_OFFSET(nr) ((nr) % BITS_PER_BYTE)
17#endif
18
19#define IS_IMMEDIATE(nr) (__builtin_constant_p(nr))
20
21static inline void __set_bit(int nr, volatile unsigned long *addr)
22{
23 if (IS_IMMEDIATE(nr)) {
24 __asm__ __volatile__ (
25 "bset.b %1, @(%O2,%0) ! __set_bit\n\t"
26 : "+r" (addr)
27 : "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr))
28 : "t", "memory"
29 );
30 } else {
31 unsigned long mask = BIT_MASK(nr);
32 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
33
34 *p |= mask;
35 }
36}
37
38static inline void __clear_bit(int nr, volatile unsigned long *addr)
39{
40 if (IS_IMMEDIATE(nr)) {
41 __asm__ __volatile__ (
42 "bclr.b %1, @(%O2,%0) ! __clear_bit\n\t"
43 : "+r" (addr)
44 : "i" (BYTE_OFFSET(nr)),
45 "i" (BYTE_NUMBER(nr))
46 : "t", "memory"
47 );
48 } else {
49 unsigned long mask = BIT_MASK(nr);
50 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
51
52 *p &= ~mask;
53 }
54}
55
56/**
57 * __change_bit - Toggle a bit in memory
58 * @nr: the bit to change
59 * @addr: the address to start counting from
60 *
61 * Unlike change_bit(), this function is non-atomic and may be reordered.
62 * If it's called on the same region of memory simultaneously, the effect
63 * may be that only one operation succeeds.
64 */
65static inline void __change_bit(int nr, volatile unsigned long *addr)
66{
67 if (IS_IMMEDIATE(nr)) {
68 __asm__ __volatile__ (
69 "bxor.b %1, @(%O2,%0) ! __change_bit\n\t"
70 : "+r" (addr)
71 : "i" (BYTE_OFFSET(nr)),
72 "i" (BYTE_NUMBER(nr))
73 : "t", "memory"
74 );
75 } else {
76 unsigned long mask = BIT_MASK(nr);
77 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
78
79 *p ^= mask;
80 }
81}
82
83/**
84 * __test_and_set_bit - Set a bit and return its old value
85 * @nr: Bit to set
86 * @addr: Address to count from
87 *
88 * This operation is non-atomic and can be reordered.
89 * If two examples of this operation race, one can appear to succeed
90 * but actually fail. You must protect multiple accesses with a lock.
91 */
92static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
93{
94 unsigned long mask = BIT_MASK(nr);
95 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
96 unsigned long old = *p;
97
98 *p = old | mask;
99 return (old & mask) != 0;
100}
101
102/**
103 * __test_and_clear_bit - Clear a bit and return its old value
104 * @nr: Bit to clear
105 * @addr: Address to count from
106 *
107 * This operation is non-atomic and can be reordered.
108 * If two examples of this operation race, one can appear to succeed
109 * but actually fail. You must protect multiple accesses with a lock.
110 */
111static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
112{
113 unsigned long mask = BIT_MASK(nr);
114 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
115 unsigned long old = *p;
116
117 *p = old & ~mask;
118 return (old & mask) != 0;
119}
120
121/* WARNING: non atomic and it can be reordered! */
122static inline int __test_and_change_bit(int nr,
123 volatile unsigned long *addr)
124{
125 unsigned long mask = BIT_MASK(nr);
126 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
127 unsigned long old = *p;
128
129 *p = old ^ mask;
130 return (old & mask) != 0;
131}
132
133/**
134 * test_bit - Determine whether a bit is set
135 * @nr: bit number to test
136 * @addr: Address to start counting from
137 */
138static inline int test_bit(int nr, const volatile unsigned long *addr)
139{
140 return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
141}
142
143#endif /* __ASM_SH_BITOPS_OP32_H */