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 #include <asm-generic/bitops/fls.h> 25 #include <asm-generic/bitops/__fls.h> 26 #include <asm-generic/bitops/fls64.h> 27 #include <asm-generic/bitops/__ffs.h> 28 29 #define smp_mb__before_clear_bit() do { } while (0) 30 #define smp_mb__after_clear_bit() do { } while (0) 31 32 /* 33 * Function prototypes to keep gcc -Wall happy. 34 */ 35 extern void set_bit(int nr, void *addr); 36 37 static inline void __set_bit(int nr, void *addr) 38 { 39 int *a = (int *)addr; 40 int mask; 41 42 a += nr >> 5; 43 mask = 1 << (nr & 0x1f); 44 *a |= mask; 45 } 46 47 extern void clear_bit(int nr, void *addr); 48 49 static inline void __clear_bit(int nr, void *addr) 50 { 51 int *a = (int *)addr; 52 int mask; 53 unsigned long flags; 54 55 a += nr >> 5; 56 mask = 1 << (nr & 0x1f); 57 local_irq_save(flags); 58 *a &= ~mask; 59 local_irq_restore(flags); 60 } 61 62 extern void change_bit(int nr, void *addr); 63 64 static inline void __change_bit(int nr, void *addr) 65 { 66 int mask; 67 unsigned long *ADDR = (unsigned long *)addr; 68 69 ADDR += nr >> 5; 70 mask = 1 << (nr & 31); 71 *ADDR ^= mask; 72 } 73 74 extern int test_and_set_bit(int nr, void *addr); 75 76 static inline int __test_and_set_bit(int nr, void *addr) 77 { 78 int mask, retval; 79 unsigned int *a = (unsigned int *)addr; 80 81 a += nr >> 5; 82 mask = 1 << (nr & 0x1f); 83 retval = (mask & *a) != 0; 84 *a |= mask; 85 return retval; 86 } 87 88 extern int test_and_clear_bit(int nr, void *addr); 89 90 static inline int __test_and_clear_bit(int nr, void *addr) 91 { 92 int mask, retval; 93 unsigned int *a = (unsigned int *)addr; 94 95 a += nr >> 5; 96 mask = 1 << (nr & 0x1f); 97 retval = (mask & *a) != 0; 98 *a &= ~mask; 99 return retval; 100 } 101 102 extern int test_and_change_bit(int nr, void *addr); 103 104 static inline int __test_and_change_bit(int nr, void *addr) 105 { 106 int mask, retval; 107 unsigned int *a = (unsigned int *)addr; 108 109 a += nr >> 5; 110 mask = 1 << (nr & 0x1f); 111 retval = (mask & *a) != 0; 112 *a ^= mask; 113 return retval; 114 } 115 116 extern int find_first_zero_bit(void *addr, unsigned size); 117 extern int find_next_zero_bit(void *addr, int size, int offset); 118 119 /* 120 * This routine doesn't need to be atomic. 121 */ 122 static inline int test_bit(int nr, const void *addr) 123 { 124 return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7)); 125 } 126 127 /* 128 * ffz = Find First Zero in word. Undefined if no zero exists, 129 * so code should check against ~0UL first.. 130 */ 131 static inline unsigned long ffz(unsigned long word) 132 { 133 int k; 134 135 word = ~word; 136 k = 31; 137 if (word & 0x0000ffff) { 138 k -= 16; word <<= 16; 139 } 140 if (word & 0x00ff0000) { 141 k -= 8; word <<= 8; 142 } 143 if (word & 0x0f000000) { 144 k -= 4; word <<= 4; 145 } 146 if (word & 0x30000000) { 147 k -= 2; word <<= 2; 148 } 149 if (word & 0x40000000) 150 k -= 1; 151 152 return k; 153 } 154 155 /* 156 * ffs: find first bit set. This is defined the same way as 157 * the libc and compiler builtin ffs routines, therefore 158 * differs in spirit from the above ffz (man ffs). 159 */ 160 161 /* 162 * redefined in include/linux/bitops.h 163 * #define ffs(x) generic_ffs(x) 164 */ 165 166 /* 167 * hweightN: returns the hamming weight (i.e. the number 168 * of bits set) of a N-bit word 169 */ 170 171 #define hweight32(x) generic_hweight32(x) 172 #define hweight16(x) generic_hweight16(x) 173 #define hweight8(x) generic_hweight8(x) 174 175 #define ext2_set_bit test_and_set_bit 176 #define ext2_clear_bit test_and_clear_bit 177 #define ext2_test_bit test_bit 178 #define ext2_find_first_zero_bit find_first_zero_bit 179 #define ext2_find_next_zero_bit find_next_zero_bit 180 181 /* Bitmap functions for the minix filesystem. */ 182 #define minix_test_and_set_bit(nr, addr) test_and_set_bit(nr, addr) 183 #define minix_set_bit(nr, addr) set_bit(nr, addr) 184 #define minix_test_and_clear_bit(nr, addr) test_and_clear_bit(nr, addr) 185 #define minix_test_bit(nr, addr) test_bit(nr, addr) 186 #define minix_find_first_zero_bit(addr, size) find_first_zero_bit(addr, size) 187 188 #endif /* __KERNEL__ */ 189 190 #endif /* __ASM_NDS_BITOPS_H */ 191