xref: /openbmc/linux/arch/sh/include/asm/bitops-op32.h (revision 165f2d28)
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 static inline void __set_bit(int nr, volatile unsigned long *addr)
20 {
21 	if (__builtin_constant_p(nr)) {
22 		__asm__ __volatile__ (
23 			"bset.b %1, @(%O2,%0)		! __set_bit\n\t"
24 			: "+r" (addr)
25 			: "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr))
26 			: "t", "memory"
27 		);
28 	} else {
29 		unsigned long mask = BIT_MASK(nr);
30 		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
31 
32 		*p |= mask;
33 	}
34 }
35 
36 static inline void __clear_bit(int nr, volatile unsigned long *addr)
37 {
38 	if (__builtin_constant_p(nr)) {
39 		__asm__ __volatile__ (
40 			"bclr.b %1, @(%O2,%0)		! __clear_bit\n\t"
41 			: "+r" (addr)
42 			: "i" (BYTE_OFFSET(nr)),
43 			  "i" (BYTE_NUMBER(nr))
44 			: "t", "memory"
45 		);
46 	} else {
47 		unsigned long mask = BIT_MASK(nr);
48 		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
49 
50 		*p &= ~mask;
51 	}
52 }
53 
54 /**
55  * __change_bit - Toggle a bit in memory
56  * @nr: the bit to change
57  * @addr: the address to start counting from
58  *
59  * Unlike change_bit(), this function is non-atomic and may be reordered.
60  * If it's called on the same region of memory simultaneously, the effect
61  * may be that only one operation succeeds.
62  */
63 static inline void __change_bit(int nr, volatile unsigned long *addr)
64 {
65 	if (__builtin_constant_p(nr)) {
66 		__asm__ __volatile__ (
67 			"bxor.b %1, @(%O2,%0)		! __change_bit\n\t"
68 			: "+r" (addr)
69 			: "i" (BYTE_OFFSET(nr)),
70 			  "i" (BYTE_NUMBER(nr))
71 			: "t", "memory"
72 		);
73 	} else {
74 		unsigned long mask = BIT_MASK(nr);
75 		unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
76 
77 		*p ^= mask;
78 	}
79 }
80 
81 /**
82  * __test_and_set_bit - Set a bit and return its old value
83  * @nr: Bit to set
84  * @addr: Address to count from
85  *
86  * This operation is non-atomic and can be reordered.
87  * If two examples of this operation race, one can appear to succeed
88  * but actually fail.  You must protect multiple accesses with a lock.
89  */
90 static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
91 {
92 	unsigned long mask = BIT_MASK(nr);
93 	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
94 	unsigned long old = *p;
95 
96 	*p = old | mask;
97 	return (old & mask) != 0;
98 }
99 
100 /**
101  * __test_and_clear_bit - Clear a bit and return its old value
102  * @nr: Bit to clear
103  * @addr: Address to count from
104  *
105  * This operation is non-atomic and can be reordered.
106  * If two examples of this operation race, one can appear to succeed
107  * but actually fail.  You must protect multiple accesses with a lock.
108  */
109 static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
110 {
111 	unsigned long mask = BIT_MASK(nr);
112 	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
113 	unsigned long old = *p;
114 
115 	*p = old & ~mask;
116 	return (old & mask) != 0;
117 }
118 
119 /* WARNING: non atomic and it can be reordered! */
120 static inline int __test_and_change_bit(int nr,
121 					    volatile unsigned long *addr)
122 {
123 	unsigned long mask = BIT_MASK(nr);
124 	unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
125 	unsigned long old = *p;
126 
127 	*p = old ^ mask;
128 	return (old & mask) != 0;
129 }
130 
131 /**
132  * test_bit - Determine whether a bit is set
133  * @nr: bit number to test
134  * @addr: Address to start counting from
135  */
136 static inline int test_bit(int nr, const volatile unsigned long *addr)
137 {
138 	return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
139 }
140 
141 #endif /* __ASM_SH_BITOPS_OP32_H */
142