1 | /* |
2 | * This file is subject to the terms and conditions of the GNU General Public |
3 | * License. See the file "COPYING" in the main directory of this archive |
4 | * for more details. |
5 | * |
6 | * Copyright (c) 1994-1997, 99, 2000, 06, 07 Ralf Baechle (ralf@linux-mips.org) |
7 | * Copyright (c) 1999, 2000 Silicon Graphics, Inc. |
8 | */ |
9 | #include <linux/bitops.h> |
10 | #include <linux/bits.h> |
11 | #include <linux/irqflags.h> |
12 | #include <linux/export.h> |
13 | |
14 | |
15 | /** |
16 | * __mips_set_bit - Atomically set a bit in memory. This is called by |
17 | * set_bit() if it cannot find a faster solution. |
18 | * @nr: the bit to set |
19 | * @addr: the address to start counting from |
20 | */ |
21 | void __mips_set_bit(unsigned long nr, volatile unsigned long *addr) |
22 | { |
23 | volatile unsigned long *a = &addr[BIT_WORD(nr)]; |
24 | unsigned int bit = nr % BITS_PER_LONG; |
25 | unsigned long mask; |
26 | unsigned long flags; |
27 | |
28 | mask = 1UL << bit; |
29 | raw_local_irq_save(flags); |
30 | *a |= mask; |
31 | raw_local_irq_restore(flags); |
32 | } |
33 | EXPORT_SYMBOL(__mips_set_bit); |
34 | |
35 | |
36 | /** |
37 | * __mips_clear_bit - Clears a bit in memory. This is called by clear_bit() if |
38 | * it cannot find a faster solution. |
39 | * @nr: Bit to clear |
40 | * @addr: Address to start counting from |
41 | */ |
42 | void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr) |
43 | { |
44 | volatile unsigned long *a = &addr[BIT_WORD(nr)]; |
45 | unsigned int bit = nr % BITS_PER_LONG; |
46 | unsigned long mask; |
47 | unsigned long flags; |
48 | |
49 | mask = 1UL << bit; |
50 | raw_local_irq_save(flags); |
51 | *a &= ~mask; |
52 | raw_local_irq_restore(flags); |
53 | } |
54 | EXPORT_SYMBOL(__mips_clear_bit); |
55 | |
56 | |
57 | /** |
58 | * __mips_change_bit - Toggle a bit in memory. This is called by change_bit() |
59 | * if it cannot find a faster solution. |
60 | * @nr: Bit to change |
61 | * @addr: Address to start counting from |
62 | */ |
63 | void __mips_change_bit(unsigned long nr, volatile unsigned long *addr) |
64 | { |
65 | volatile unsigned long *a = &addr[BIT_WORD(nr)]; |
66 | unsigned int bit = nr % BITS_PER_LONG; |
67 | unsigned long mask; |
68 | unsigned long flags; |
69 | |
70 | mask = 1UL << bit; |
71 | raw_local_irq_save(flags); |
72 | *a ^= mask; |
73 | raw_local_irq_restore(flags); |
74 | } |
75 | EXPORT_SYMBOL(__mips_change_bit); |
76 | |
77 | |
78 | /** |
79 | * __mips_test_and_set_bit_lock - Set a bit and return its old value. This is |
80 | * called by test_and_set_bit_lock() if it cannot find a faster solution. |
81 | * @nr: Bit to set |
82 | * @addr: Address to count from |
83 | */ |
84 | int __mips_test_and_set_bit_lock(unsigned long nr, |
85 | volatile unsigned long *addr) |
86 | { |
87 | volatile unsigned long *a = &addr[BIT_WORD(nr)]; |
88 | unsigned int bit = nr % BITS_PER_LONG; |
89 | unsigned long mask; |
90 | unsigned long flags; |
91 | int res; |
92 | |
93 | mask = 1UL << bit; |
94 | raw_local_irq_save(flags); |
95 | res = (mask & *a) != 0; |
96 | *a |= mask; |
97 | raw_local_irq_restore(flags); |
98 | return res; |
99 | } |
100 | EXPORT_SYMBOL(__mips_test_and_set_bit_lock); |
101 | |
102 | |
103 | /** |
104 | * __mips_test_and_clear_bit - Clear a bit and return its old value. This is |
105 | * called by test_and_clear_bit() if it cannot find a faster solution. |
106 | * @nr: Bit to clear |
107 | * @addr: Address to count from |
108 | */ |
109 | int __mips_test_and_clear_bit(unsigned long nr, volatile unsigned long *addr) |
110 | { |
111 | volatile unsigned long *a = &addr[BIT_WORD(nr)]; |
112 | unsigned int bit = nr % BITS_PER_LONG; |
113 | unsigned long mask; |
114 | unsigned long flags; |
115 | int res; |
116 | |
117 | mask = 1UL << bit; |
118 | raw_local_irq_save(flags); |
119 | res = (mask & *a) != 0; |
120 | *a &= ~mask; |
121 | raw_local_irq_restore(flags); |
122 | return res; |
123 | } |
124 | EXPORT_SYMBOL(__mips_test_and_clear_bit); |
125 | |
126 | |
127 | /** |
128 | * __mips_test_and_change_bit - Change a bit and return its old value. This is |
129 | * called by test_and_change_bit() if it cannot find a faster solution. |
130 | * @nr: Bit to change |
131 | * @addr: Address to count from |
132 | */ |
133 | int __mips_test_and_change_bit(unsigned long nr, volatile unsigned long *addr) |
134 | { |
135 | volatile unsigned long *a = &addr[BIT_WORD(nr)]; |
136 | unsigned int bit = nr % BITS_PER_LONG; |
137 | unsigned long mask; |
138 | unsigned long flags; |
139 | int res; |
140 | |
141 | mask = 1UL << bit; |
142 | raw_local_irq_save(flags); |
143 | res = (mask & *a) != 0; |
144 | *a ^= mask; |
145 | raw_local_irq_restore(flags); |
146 | return res; |
147 | } |
148 | EXPORT_SYMBOL(__mips_test_and_change_bit); |
149 | |
150 | bool __mips_xor_is_negative_byte(unsigned long mask, |
151 | volatile unsigned long *addr) |
152 | { |
153 | unsigned long flags; |
154 | unsigned long data; |
155 | |
156 | raw_local_irq_save(flags); |
157 | data = *addr; |
158 | *addr = data ^ mask; |
159 | raw_local_irq_restore(flags); |
160 | |
161 | return (data & BIT(7)) != 0; |
162 | } |
163 | |