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
  47#define PLATFORM__SET_BIT
  48
  49extern void clear_bit(int nr, void *addr);
  50
  51static 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
  66extern void change_bit(int nr, void *addr);
  67
  68static 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
  78extern int test_and_set_bit(int nr, void *addr);
  79
  80static 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
  92extern int test_and_clear_bit(int nr, void *addr);
  93
  94static 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
 106extern int test_and_change_bit(int nr, void *addr);
 107
 108static 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
 120extern int find_first_zero_bit(void *addr, unsigned size);
 121extern int find_next_zero_bit(void *addr, int size, int offset);
 122
 123/*
 124 * This routine doesn't need to be atomic.
 125 */
 126static 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 */
 135static 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