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#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 */
  35extern void set_bit(int nr, void *addr);
  36
  37static 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
  47extern void clear_bit(int nr, void *addr);
  48
  49static 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
  62extern void change_bit(int nr, void *addr);
  63
  64static 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
  74extern int test_and_set_bit(int nr, void *addr);
  75
  76static 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
  88extern int test_and_clear_bit(int nr, void *addr);
  89
  90static 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
 102extern int test_and_change_bit(int nr, void *addr);
 103
 104static 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
 116extern int find_first_zero_bit(void *addr, unsigned size);
 117extern int find_next_zero_bit(void *addr, int size, int offset);
 118
 119/*
 120 * This routine doesn't need to be atomic.
 121 */
 122static 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 */
 131static 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