xref: /linux/arch/sh/include/asm/bitops-op32.h (revision 44f57d78)
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 
21 static 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 
38 static 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  */
65 static 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  */
92 static 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  */
111 static 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! */
122 static 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  */
138 static 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 */
144