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

   1#ifndef __ASM_SH_BITOPS_H
   2#define __ASM_SH_BITOPS_H
   3
   4#include <asm-generic/bitops/fls.h>
   5#include <asm-generic/bitops/__fls.h>
   6#include <asm-generic/bitops/fls64.h>
   7#include <asm-generic/bitops/__ffs.h>
   8
   9#ifdef __KERNEL__
  10#include <asm/irqflags.h>
  11/* For __swab32 */
  12#include <asm/byteorder.h>
  13
  14static inline void set_bit(int nr, volatile void * addr)
  15{
  16        int     mask;
  17        volatile unsigned int *a = addr;
  18        unsigned long flags;
  19
  20        a += nr >> 5;
  21        mask = 1 << (nr & 0x1f);
  22        local_irq_save(flags);
  23        *a |= mask;
  24        local_irq_restore(flags);
  25}
  26
  27/*
  28 * clear_bit() doesn't provide any barrier for the compiler.
  29 */
  30#define smp_mb__before_clear_bit()      barrier()
  31#define smp_mb__after_clear_bit()       barrier()
  32static inline void clear_bit(int nr, volatile void * addr)
  33{
  34        int     mask;
  35        volatile unsigned int *a = addr;
  36        unsigned long flags;
  37
  38        a += nr >> 5;
  39        mask = 1 << (nr & 0x1f);
  40        local_irq_save(flags);
  41        *a &= ~mask;
  42        local_irq_restore(flags);
  43}
  44
  45static inline void change_bit(int nr, volatile void * addr)
  46{
  47        int     mask;
  48        volatile unsigned int *a = addr;
  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
  58static inline int test_and_set_bit(int nr, volatile void * addr)
  59{
  60        int     mask, retval;
  61        volatile unsigned int *a = addr;
  62        unsigned long flags;
  63
  64        a += nr >> 5;
  65        mask = 1 << (nr & 0x1f);
  66        local_irq_save(flags);
  67        retval = (mask & *a) != 0;
  68        *a |= mask;
  69        local_irq_restore(flags);
  70
  71        return retval;
  72}
  73
  74static inline int test_and_clear_bit(int nr, volatile void * addr)
  75{
  76        int     mask, retval;
  77        volatile unsigned int *a = addr;
  78        unsigned long flags;
  79
  80        a += nr >> 5;
  81        mask = 1 << (nr & 0x1f);
  82        local_irq_save(flags);
  83        retval = (mask & *a) != 0;
  84        *a &= ~mask;
  85        local_irq_restore(flags);
  86
  87        return retval;
  88}
  89
  90static inline int test_and_change_bit(int nr, volatile void * addr)
  91{
  92        int     mask, retval;
  93        volatile unsigned int *a = addr;
  94        unsigned long flags;
  95
  96        a += nr >> 5;
  97        mask = 1 << (nr & 0x1f);
  98        local_irq_save(flags);
  99        retval = (mask & *a) != 0;
 100        *a ^= mask;
 101        local_irq_restore(flags);
 102
 103        return retval;
 104}
 105
 106static inline unsigned long ffz(unsigned long word)
 107{
 108        unsigned long result;
 109
 110        __asm__("1:\n\t"
 111                "shlr   %1\n\t"
 112                "bt/s   1b\n\t"
 113                " add   #1, %0"
 114                : "=r" (result), "=r" (word)
 115                : "0" (~0L), "1" (word)
 116                : "t");
 117        return result;
 118}
 119
 120/**
 121 * ffs - find first bit in word.
 122 * @word: The word to search
 123 *
 124 * Undefined if no bit exists, so code should check against 0 first.
 125 */
 126static inline int ffs (int x)
 127{
 128        int r = 1;
 129
 130        if (!x)
 131                return 0;
 132        if (!(x & 0xffff)) {
 133                x >>= 16;
 134                r += 16;
 135        }
 136        if (!(x & 0xff)) {
 137                x >>= 8;
 138                r += 8;
 139        }
 140        if (!(x & 0xf)) {
 141                x >>= 4;
 142                r += 4;
 143        }
 144        if (!(x & 3)) {
 145                x >>= 2;
 146                r += 2;
 147        }
 148        if (!(x & 1)) {
 149                x >>= 1;
 150                r += 1;
 151        }
 152        return r;
 153}
 154#define PLATFORM_FFS
 155
 156#endif /* __KERNEL__ */
 157
 158#endif /* __ASM_SH_BITOPS_H */
 159