arch/tile/include/asm/cmpxchg.h

   1 /*
   2  * cmpxchg.h -- forked from asm/atomic.h with this copyright:
   3  *
   4  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   5  *
   6  *   This program is free software; you can redistribute it and/or
   7  *   modify it under the terms of the GNU General Public License
   8  *   as published by the Free Software Foundation, version 2.
   9  *
  10  *   This program is distributed in the hope that it will be useful, but
  11  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  13  *   NON INFRINGEMENT.  See the GNU General Public License for
  14  *   more details.
  15  *
  16  */
  17
  18 #ifndef _ASM_TILE_CMPXCHG_H
  19 #define _ASM_TILE_CMPXCHG_H
  20
  21 #ifndef __ASSEMBLY__
  22
  23 #include <asm/barrier.h>
  24
  25 /* Nonexistent functions intended to cause compile errors. */
  26 extern void __xchg_called_with_bad_pointer(void)
  27         __compiletime_error("Bad argument size for xchg");
  28 extern void __cmpxchg_called_with_bad_pointer(void)
  29         __compiletime_error("Bad argument size for cmpxchg");
  30
  31 #ifndef __tilegx__
  32
  33 /* Note the _atomic_xxx() routines include a final mb(). */
  34 int _atomic_xchg(int *ptr, int n);
  35 int _atomic_xchg_add(int *v, int i);
  36 int _atomic_xchg_add_unless(int *v, int a, int u);
  37 int _atomic_cmpxchg(int *ptr, int o, int n);
  38 u64 _atomic64_xchg(u64 *v, u64 n);
  39 u64 _atomic64_xchg_add(u64 *v, u64 i);
  40 u64 _atomic64_xchg_add_unless(u64 *v, u64 a, u64 u);
  41 u64 _atomic64_cmpxchg(u64 *v, u64 o, u64 n);
  42
  43 #define xchg(ptr, n)                                                    \
  44         ({                                                              \
  45                 if (sizeof(*(ptr)) != 4)                                \
  46                         __xchg_called_with_bad_pointer();               \
  47                 smp_mb();                                               \
  48                 (typeof(*(ptr)))_atomic_xchg((int *)(ptr), (int)(n));   \
  49         })
  50
  51 #define cmpxchg(ptr, o, n)                                              \
  52         ({                                                              \
  53                 if (sizeof(*(ptr)) != 4)                                \
  54                         __cmpxchg_called_with_bad_pointer();            \
  55                 smp_mb();                                               \
  56                 (typeof(*(ptr)))_atomic_cmpxchg((int *)ptr, (int)o, (int)n); \
  57         })
  58
  59 #define xchg64(ptr, n)                                                  \
  60         ({                                                              \
  61                 if (sizeof(*(ptr)) != 8)                                \
  62                         __xchg_called_with_bad_pointer();               \
  63                 smp_mb();                                               \
  64                 (typeof(*(ptr)))_atomic64_xchg((u64 *)(ptr), (u64)(n)); \
  65         })
  66
  67 #define cmpxchg64(ptr, o, n)                                            \
  68         ({                                                              \
  69                 if (sizeof(*(ptr)) != 8)                                \
  70                         __cmpxchg_called_with_bad_pointer();            \
  71                 smp_mb();                                               \
  72                 (typeof(*(ptr)))_atomic64_cmpxchg((u64 *)ptr, (u64)o, (u64)n); \
  73         })
  74
  75 #else
  76
  77 #define xchg(ptr, n)                                                    \
  78         ({                                                              \
  79                 typeof(*(ptr)) __x;                                     \
  80                 smp_mb();                                               \
  81                 switch (sizeof(*(ptr))) {                               \
  82                 case 4:                                                 \
  83                         __x = (typeof(__x))(unsigned long)              \
  84                                 __insn_exch4((ptr), (u32)(unsigned long)(n)); \
  85                         break;                                          \
  86                 case 8:                                                 \
  87                         __x = (typeof(__x))                     \
  88                                 __insn_exch((ptr), (unsigned long)(n)); \
  89                         break;                                          \
  90                 default:                                                \
  91                         __xchg_called_with_bad_pointer();               \
  92                         break;                                          \
  93                 }                                                       \
  94                 smp_mb();                                               \
  95                 __x;                                                    \
  96         })
  97
  98 #define cmpxchg(ptr, o, n)                                              \
  99         ({                                                              \
 100                 typeof(*(ptr)) __x;                                     \
 101                 __insn_mtspr(SPR_CMPEXCH_VALUE, (unsigned long)(o));    \
 102                 smp_mb();                                               \
 103                 switch (sizeof(*(ptr))) {                               \
 104                 case 4:                                                 \
 105                         __x = (typeof(__x))(unsigned long)              \
 106                                 __insn_cmpexch4((ptr), (u32)(unsigned long)(n)); \
 107                         break;                                          \
 108                 case 8:                                                 \
 109                         __x = (typeof(__x))__insn_cmpexch((ptr), (u64)(n)); \
 110                         break;                                          \
 111                 default:                                                \
 112                         __cmpxchg_called_with_bad_pointer();            \
 113                         break;                                          \
 114                 }                                                       \
 115                 smp_mb();                                               \
 116                 __x;                                                    \
 117         })
 118
 119 #define xchg64 xchg
 120 #define cmpxchg64 cmpxchg
 121
 122 #endif
 123
 124 #define tas(ptr) xchg((ptr), 1)
 125
 126 #endif /* __ASSEMBLY__ */
 127
 128 #endif /* _ASM_TILE_CMPXCHG_H */