1 /* 2 * Copyright 1995, Russell King. 3 * Various bits and pieces copyrights include: 4 * Linus Torvalds (test_bit). 5 * 6 * Copyright (C) 2011 Andes Technology Corporation 7 * Shawn Lin, Andes Technology Corporation <nobuhiro@andestech.com> 8 * 9 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). 10 * 11 * Please note that the code in this file should never be included 12 * from user space. Many of these are not implemented in assembler 13 * since they would be too costly. Also, they require priviledged 14 * instructions (which are not available from user mode) to ensure 15 * that they are atomic. 16 */ 17 18 #ifndef __ASM_NDS_BITOPS_H 19 #define __ASM_NDS_BITOPS_H 20 21 #ifdef __KERNEL__ 22 23 #include <asm/system.h> 24 25 #define smp_mb__before_clear_bit() do { } while (0) 26 #define smp_mb__after_clear_bit() do { } while (0) 27 28 /* 29 * Function prototypes to keep gcc -Wall happy. 30 */ 31 extern void set_bit(int nr, void *addr); 32 33 static inline void __set_bit(int nr, void *addr) 34 { 35 int *a = (int *)addr; 36 int mask; 37 38 a += nr >> 5; 39 mask = 1 << (nr & 0x1f); 40 *a |= mask; 41 } 42 43 extern void clear_bit(int nr, void *addr); 44 45 static inline void __clear_bit(int nr, void *addr) 46 { 47 int *a = (int *)addr; 48 int mask; 49 unsigned long flags; 50 51 a += nr >> 5; 52 mask = 1 << (nr & 0x1f); 53 local_irq_save(flags); 54 *a &= ~mask; 55 local_irq_restore(flags); 56 } 57 58 extern void change_bit(int nr, void *addr); 59 60 static inline void __change_bit(int nr, void *addr) 61 { 62 int mask; 63 unsigned long *ADDR = (unsigned long *)addr; 64 65 ADDR += nr >> 5; 66 mask = 1 << (nr & 31); 67 *ADDR ^= mask; 68 } 69 70 extern int test_and_set_bit(int nr, void *addr); 71 72 static inline int __test_and_set_bit(int nr, void *addr) 73 { 74 int mask, retval; 75 unsigned int *a = (unsigned int *)addr; 76 77 a += nr >> 5; 78 mask = 1 << (nr & 0x1f); 79 retval = (mask & *a) != 0; 80 *a |= mask; 81 return retval; 82 } 83 84 extern int test_and_clear_bit(int nr, void *addr); 85 86 static inline int __test_and_clear_bit(int nr, void *addr) 87 { 88 int mask, retval; 89 unsigned int *a = (unsigned int *)addr; 90 91 a += nr >> 5; 92 mask = 1 << (nr & 0x1f); 93 retval = (mask & *a) != 0; 94 *a &= ~mask; 95 return retval; 96 } 97 98 extern int test_and_change_bit(int nr, void *addr); 99 100 static inline int __test_and_change_bit(int nr, void *addr) 101 { 102 int mask, retval; 103 unsigned int *a = (unsigned int *)addr; 104 105 a += nr >> 5; 106 mask = 1 << (nr & 0x1f); 107 retval = (mask & *a) != 0; 108 *a ^= mask; 109 return retval; 110 } 111 112 extern int find_first_zero_bit(void *addr, unsigned size); 113 extern int find_next_zero_bit(void *addr, int size, int offset); 114 115 /* 116 * This routine doesn't need to be atomic. 117 */ 118 static inline int test_bit(int nr, const void *addr) 119 { 120 return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7)); 121 } 122 123 /* 124 * ffz = Find First Zero in word. Undefined if no zero exists, 125 * so code should check against ~0UL first.. 126 */ 127 static inline unsigned long ffz(unsigned long word) 128 { 129 int k; 130 131 word = ~word; 132 k = 31; 133 if (word & 0x0000ffff) { 134 k -= 16; word <<= 16; 135 } 136 if (word & 0x00ff0000) { 137 k -= 8; word <<= 8; 138 } 139 if (word & 0x0f000000) { 140 k -= 4; word <<= 4; 141 } 142 if (word & 0x30000000) { 143 k -= 2; word <<= 2; 144 } 145 if (word & 0x40000000) 146 k -= 1; 147 148 return k; 149 } 150 151 /* 152 * ffs: find first bit set. This is defined the same way as 153 * the libc and compiler builtin ffs routines, therefore 154 * differs in spirit from the above ffz (man ffs). 155 */ 156 157 /* 158 * redefined in include/linux/bitops.h 159 * #define ffs(x) generic_ffs(x) 160 */ 161 162 /* 163 * hweightN: returns the hamming weight (i.e. the number 164 * of bits set) of a N-bit word 165 */ 166 167 #define hweight32(x) generic_hweight32(x) 168 #define hweight16(x) generic_hweight16(x) 169 #define hweight8(x) generic_hweight8(x) 170 171 #define ext2_set_bit test_and_set_bit 172 #define ext2_clear_bit test_and_clear_bit 173 #define ext2_test_bit test_bit 174 #define ext2_find_first_zero_bit find_first_zero_bit 175 #define ext2_find_next_zero_bit find_next_zero_bit 176 177 /* Bitmap functions for the minix filesystem. */ 178 #define minix_test_and_set_bit(nr, addr) test_and_set_bit(nr, addr) 179 #define minix_set_bit(nr, addr) set_bit(nr, addr) 180 #define minix_test_and_clear_bit(nr, addr) test_and_clear_bit(nr, addr) 181 #define minix_test_bit(nr, addr) test_bit(nr, addr) 182 #define minix_find_first_zero_bit(addr, size) find_first_zero_bit(addr, size) 183 184 #endif /* __KERNEL__ */ 185 186 #endif /* __ASM_NDS_BITOPS_H */ 187