xref: /linux/arch/sh/include/asm/bitops-op32.h (revision 4359a011e259a4608afc7fb3635370c9d4ba5943)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_BITOPS_OP32_H
3 #define __ASM_SH_BITOPS_OP32_H
4 
5 #include <linux/bits.h>
6 
7 /*
8  * The bit modifying instructions on SH-2A are only capable of working
9  * with a 3-bit immediate, which signifies the shift position for the bit
10  * being worked on.
11  */
12 #if defined(__BIG_ENDIAN)
13 #define BITOP_LE_SWIZZLE	((BITS_PER_LONG-1) & ~0x7)
14 #define BYTE_NUMBER(nr)		((nr ^ BITOP_LE_SWIZZLE) / BITS_PER_BYTE)
15 #define BYTE_OFFSET(nr)		((nr ^ BITOP_LE_SWIZZLE) % BITS_PER_BYTE)
16 #else
17 #define BYTE_NUMBER(nr)		((nr) / BITS_PER_BYTE)
18 #define BYTE_OFFSET(nr)		((nr) % BITS_PER_BYTE)
19 #endif
20 
21 static __always_inline void
22 arch___set_bit(unsigned long nr, volatile unsigned long *addr)
23 {
24 	if (__builtin_constant_p(nr)) {
25 		__asm__ __volatile__ (
26 			"bset.b %1, @(%O2,%0)		! __set_bit\n\t"
27 			: "+r" (addr)
28 			: "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr))
29 			: "t", "memory"
30 		);
31 	} else {
32 		unsigned long mask = BIT_MASK(nr);
33 		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
34 
35 		*p |= mask;
36 	}
37 }
38 
39 static __always_inline void
40 arch___clear_bit(unsigned long nr, volatile unsigned long *addr)
41 {
42 	if (__builtin_constant_p(nr)) {
43 		__asm__ __volatile__ (
44 			"bclr.b %1, @(%O2,%0)		! __clear_bit\n\t"
45 			: "+r" (addr)
46 			: "i" (BYTE_OFFSET(nr)),
47 			  "i" (BYTE_NUMBER(nr))
48 			: "t", "memory"
49 		);
50 	} else {
51 		unsigned long mask = BIT_MASK(nr);
52 		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
53 
54 		*p &= ~mask;
55 	}
56 }
57 
58 /**
59  * arch___change_bit - Toggle a bit in memory
60  * @nr: the bit to change
61  * @addr: the address to start counting from
62  *
63  * Unlike change_bit(), this function is non-atomic and may be reordered.
64  * If it's called on the same region of memory simultaneously, the effect
65  * may be that only one operation succeeds.
66  */
67 static __always_inline void
68 arch___change_bit(unsigned long nr, volatile unsigned long *addr)
69 {
70 	if (__builtin_constant_p(nr)) {
71 		__asm__ __volatile__ (
72 			"bxor.b %1, @(%O2,%0)		! __change_bit\n\t"
73 			: "+r" (addr)
74 			: "i" (BYTE_OFFSET(nr)),
75 			  "i" (BYTE_NUMBER(nr))
76 			: "t", "memory"
77 		);
78 	} else {
79 		unsigned long mask = BIT_MASK(nr);
80 		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
81 
82 		*p ^= mask;
83 	}
84 }
85 
86 /**
87  * arch___test_and_set_bit - Set a bit and return its old value
88  * @nr: Bit to set
89  * @addr: Address to count from
90  *
91  * This operation is non-atomic and can be reordered.
92  * If two examples of this operation race, one can appear to succeed
93  * but actually fail.  You must protect multiple accesses with a lock.
94  */
95 static __always_inline bool
96 arch___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
97 {
98 	unsigned long mask = BIT_MASK(nr);
99 	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
100 	unsigned long old = *p;
101 
102 	*p = old | mask;
103 	return (old & mask) != 0;
104 }
105 
106 /**
107  * arch___test_and_clear_bit - Clear a bit and return its old value
108  * @nr: Bit to clear
109  * @addr: Address to count from
110  *
111  * This operation is non-atomic and can be reordered.
112  * If two examples of this operation race, one can appear to succeed
113  * but actually fail.  You must protect multiple accesses with a lock.
114  */
115 static __always_inline bool
116 arch___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
117 {
118 	unsigned long mask = BIT_MASK(nr);
119 	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
120 	unsigned long old = *p;
121 
122 	*p = old & ~mask;
123 	return (old & mask) != 0;
124 }
125 
126 /* WARNING: non atomic and it can be reordered! */
127 static __always_inline bool
128 arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
129 {
130 	unsigned long mask = BIT_MASK(nr);
131 	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
132 	unsigned long old = *p;
133 
134 	*p = old ^ mask;
135 	return (old & mask) != 0;
136 }
137 
138 #define arch_test_bit generic_test_bit
139 #define arch_test_bit_acquire generic_test_bit_acquire
140 
141 #include <asm-generic/bitops/non-instrumented-non-atomic.h>
142 
143 #endif /* __ASM_SH_BITOPS_OP32_H */
144