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 #define PLATFORM__SET_BIT 48 49 extern void clear_bit(int nr, void *addr); 50 51 static inline void __clear_bit(int nr, void *addr) 52 { 53 int *a = (int *)addr; 54 int mask; 55 unsigned long flags; 56 57 a += nr >> 5; 58 mask = 1 << (nr & 0x1f); 59 local_irq_save(flags); 60 *a &= ~mask; 61 local_irq_restore(flags); 62 } 63 64 #define PLATFORM__CLEAR_BIT 65 66 extern void change_bit(int nr, void *addr); 67 68 static inline void __change_bit(int nr, void *addr) 69 { 70 int mask; 71 unsigned long *ADDR = (unsigned long *)addr; 72 73 ADDR += nr >> 5; 74 mask = 1 << (nr & 31); 75 *ADDR ^= mask; 76 } 77 78 extern int test_and_set_bit(int nr, void *addr); 79 80 static inline int __test_and_set_bit(int nr, void *addr) 81 { 82 int mask, retval; 83 unsigned int *a = (unsigned int *)addr; 84 85 a += nr >> 5; 86 mask = 1 << (nr & 0x1f); 87 retval = (mask & *a) != 0; 88 *a |= mask; 89 return retval; 90 } 91 92 extern int test_and_clear_bit(int nr, void *addr); 93 94 static inline int __test_and_clear_bit(int nr, void *addr) 95 { 96 int mask, retval; 97 unsigned int *a = (unsigned int *)addr; 98 99 a += nr >> 5; 100 mask = 1 << (nr & 0x1f); 101 retval = (mask & *a) != 0; 102 *a &= ~mask; 103 return retval; 104 } 105 106 extern int test_and_change_bit(int nr, void *addr); 107 108 static inline int __test_and_change_bit(int nr, void *addr) 109 { 110 int mask, retval; 111 unsigned int *a = (unsigned int *)addr; 112 113 a += nr >> 5; 114 mask = 1 << (nr & 0x1f); 115 retval = (mask & *a) != 0; 116 *a ^= mask; 117 return retval; 118 } 119 120 extern int find_first_zero_bit(void *addr, unsigned size); 121 extern int find_next_zero_bit(void *addr, int size, int offset); 122 123 /* 124 * This routine doesn't need to be atomic. 125 */ 126 static inline int test_bit(int nr, const void *addr) 127 { 128 return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7)); 129 } 130 131 /* 132 * ffz = Find First Zero in word. Undefined if no zero exists, 133 * so code should check against ~0UL first.. 134 */ 135 static inline unsigned long ffz(unsigned long word) 136 { 137 int k; 138 139 word = ~word; 140 k = 31; 141 if (word & 0x0000ffff) { 142 k -= 16; word <<= 16; 143 } 144 if (word & 0x00ff0000) { 145 k -= 8; word <<= 8; 146 } 147 if (word & 0x0f000000) { 148 k -= 4; word <<= 4; 149 } 150 if (word & 0x30000000) { 151 k -= 2; word <<= 2; 152 } 153 if (word & 0x40000000) 154 k -= 1; 155 156 return k; 157 } 158 159 /* 160 * ffs: find first bit set. This is defined the same way as 161 * the libc and compiler builtin ffs routines, therefore 162 * differs in spirit from the above ffz (man ffs). 163 */ 164 165 /* 166 * redefined in include/linux/bitops.h 167 * #define ffs(x) generic_ffs(x) 168 */ 169 170 /* 171 * hweightN: returns the hamming weight (i.e. the number 172 * of bits set) of a N-bit word 173 */ 174 175 #define hweight32(x) generic_hweight32(x) 176 #define hweight16(x) generic_hweight16(x) 177 #define hweight8(x) generic_hweight8(x) 178 179 #define ext2_set_bit test_and_set_bit 180 #define ext2_clear_bit test_and_clear_bit 181 #define ext2_test_bit test_bit 182 #define ext2_find_first_zero_bit find_first_zero_bit 183 #define ext2_find_next_zero_bit find_next_zero_bit 184 185 /* Bitmap functions for the minix filesystem. */ 186 #define minix_test_and_set_bit(nr, addr) test_and_set_bit(nr, addr) 187 #define minix_set_bit(nr, addr) set_bit(nr, addr) 188 #define minix_test_and_clear_bit(nr, addr) test_and_clear_bit(nr, addr) 189 #define minix_test_bit(nr, addr) test_bit(nr, addr) 190 #define minix_find_first_zero_bit(addr, size) find_first_zero_bit(addr, size) 191 192 #endif /* __KERNEL__ */ 193 194 #endif /* __ASM_NDS_BITOPS_H */ 195