LXR uboot/arch/nds32/include/asm/bitops.h

   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 */
  31extern void set_bit(int nr, void *addr);
  32
  33static 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
  43extern void clear_bit(int nr, void *addr);
  44
  45static 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
  58extern void change_bit(int nr, void *addr);
  59
  60static 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
  70extern int test_and_set_bit(int nr, void *addr);
  71
  72static 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
  84extern int test_and_clear_bit(int nr, void *addr);
  85
  86static 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
  98extern int test_and_change_bit(int nr, void *addr);
  99
 100static 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
 112extern int find_first_zero_bit(void *addr, unsigned size);
 113extern int find_next_zero_bit(void *addr, int size, int offset);
 114
 115/*
 116 * This routine doesn't need to be atomic.
 117 */
 118static 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 */
 127static 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