arch/sh/include/asm/bitops-op32.h

   1 #ifndef __ASM_SH_BITOPS_OP32_H
   2 #define __ASM_SH_BITOPS_OP32_H
   3
   4 /*
   5  * The bit modifying instructions on SH-2A are only capable of working
   6  * with a 3-bit immediate, which signifies the shift position for the bit
   7  * being worked on.
   8  */
   9 #if defined(__BIG_ENDIAN)
  10 #define BITOP_LE_SWIZZLE        ((BITS_PER_LONG-1) & ~0x7)
  11 #define BYTE_NUMBER(nr)         ((nr ^ BITOP_LE_SWIZZLE) / BITS_PER_BYTE)
  12 #define BYTE_OFFSET(nr)         ((nr ^ BITOP_LE_SWIZZLE) % BITS_PER_BYTE)
  13 #else
  14 #define BYTE_NUMBER(nr)         ((nr) / BITS_PER_BYTE)
  15 #define BYTE_OFFSET(nr)         ((nr) % BITS_PER_BYTE)
  16 #endif
  17
  18 #define IS_IMMEDIATE(nr)        (__builtin_constant_p(nr))
  19
  20 static inline void __set_bit(int nr, volatile unsigned long *addr)
  21 {
  22         if (IS_IMMEDIATE(nr)) {
  23                 __asm__ __volatile__ (
  24                         "bset.b %1, @(%O2,%0)           ! __set_bit\n\t"
  25                         : "+r" (addr)
  26                         : "i" (BYTE_OFFSET(nr)), "i" (BYTE_NUMBER(nr))
  27                         : "t", "memory"
  28                 );
  29         } else {
  30                 unsigned long mask = BIT_MASK(nr);
  31                 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
  32
  33                 *p |= mask;
  34         }
  35 }
  36
  37 static inline void __clear_bit(int nr, volatile unsigned long *addr)
  38 {
  39         if (IS_IMMEDIATE(nr)) {
  40                 __asm__ __volatile__ (
  41                         "bclr.b %1, @(%O2,%0)           ! __clear_bit\n\t"
  42                         : "+r" (addr)
  43                         : "i" (BYTE_OFFSET(nr)),
  44                           "i" (BYTE_NUMBER(nr))
  45                         : "t", "memory"
  46                 );
  47         } else {
  48                 unsigned long mask = BIT_MASK(nr);
  49                 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
  50
  51                 *p &= ~mask;
  52         }
  53 }
  54
  55 /**
  56  * __change_bit - Toggle a bit in memory
  57  * @nr: the bit to change
  58  * @addr: the address to start counting from
  59  *
  60  * Unlike change_bit(), this function is non-atomic and may be reordered.
  61  * If it's called on the same region of memory simultaneously, the effect
  62  * may be that only one operation succeeds.
  63  */
  64 static inline void __change_bit(int nr, volatile unsigned long *addr)
  65 {
  66         if (IS_IMMEDIATE(nr)) {
  67                 __asm__ __volatile__ (
  68                         "bxor.b %1, @(%O2,%0)           ! __change_bit\n\t"
  69                         : "+r" (addr)
  70                         : "i" (BYTE_OFFSET(nr)),
  71                           "i" (BYTE_NUMBER(nr))
  72                         : "t", "memory"
  73                 );
  74         } else {
  75                 unsigned long mask = BIT_MASK(nr);
  76                 unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
  77
  78                 *p ^= mask;
  79         }
  80 }
  81
  82 /**
  83  * __test_and_set_bit - Set a bit and return its old value
  84  * @nr: Bit to set
  85  * @addr: Address to count from
  86  *
  87  * This operation is non-atomic and can be reordered.
  88  * If two examples of this operation race, one can appear to succeed
  89  * but actually fail.  You must protect multiple accesses with a lock.
  90  */
  91 static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
  92 {
  93         unsigned long mask = BIT_MASK(nr);
  94         unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
  95         unsigned long old = *p;
  96
  97         *p = old | mask;
  98         return (old & mask) != 0;
  99 }
 100
 101 /**
 102  * __test_and_clear_bit - Clear a bit and return its old value
 103  * @nr: Bit to clear
 104  * @addr: Address to count from
 105  *
 106  * This operation is non-atomic and can be reordered.
 107  * If two examples of this operation race, one can appear to succeed
 108  * but actually fail.  You must protect multiple accesses with a lock.
 109  */
 110 static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
 111 {
 112         unsigned long mask = BIT_MASK(nr);
 113         unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 114         unsigned long old = *p;
 115
 116         *p = old & ~mask;
 117         return (old & mask) != 0;
 118 }
 119
 120 /* WARNING: non atomic and it can be reordered! */
 121 static inline int __test_and_change_bit(int nr,
 122                                             volatile unsigned long *addr)
 123 {
 124         unsigned long mask = BIT_MASK(nr);
 125         unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
 126         unsigned long old = *p;
 127
 128         *p = old ^ mask;
 129         return (old & mask) != 0;
 130 }
 131
 132 /**
 133  * test_bit - Determine whether a bit is set
 134  * @nr: bit number to test
 135  * @addr: Address to start counting from
 136  */
 137 static inline int test_bit(int nr, const volatile unsigned long *addr)
 138 {
 139         return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
 140 }
 141
 142 #endif /* __ASM_SH_BITOPS_OP32_H */