sysdeps/unix/sysv/linux/m68k/coldfire/bits/atomic.h

   1 /* Copyright (C) 2010-2014 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Maxim Kuvyrkov <maxim@codesourcery.com>, 2010.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _BITS_ATOMIC_H
  20 #define _BITS_ATOMIC_H  1
  21
  22 #include <stdint.h>
  23 #include <sysdep.h>
  24 #include <bits/m68k-vdso.h>
  25
  26 /* Coldfire has no atomic compare-and-exchange operation, but the
  27    kernel provides userspace atomicity operations.  Use them.  */
  28
  29 typedef int32_t atomic32_t;
  30 typedef uint32_t uatomic32_t;
  31 typedef int_fast32_t atomic_fast32_t;
  32 typedef uint_fast32_t uatomic_fast32_t;
  33
  34 typedef intptr_t atomicptr_t;
  35 typedef uintptr_t uatomicptr_t;
  36 typedef intmax_t atomic_max_t;
  37 typedef uintmax_t uatomic_max_t;
  38
  39 #define __HAVE_64B_ATOMICS 0
  40 #define USE_ATOMIC_COMPILER_BUILTINS 0
  41
  42 /* The only basic operation needed is compare and exchange.  */
  43 /* For ColdFire we'll have to trap into the kernel mode anyway,
  44    so trap from the library rather then from the kernel wrapper.  */
  45 #ifdef SHARED
  46 # define atomic_compare_and_exchange_val_acq(mem, newval, oldval)       \
  47   ({                                                                    \
  48     /* Use temporary variables to workaround call-clobberness of        \
  49        the registers.  */                                               \
  50     __typeof (mem) _mem = mem;                                          \
  51     __typeof (oldval) _oldval = oldval;                                 \
  52     __typeof (newval) _newval = newval;                                 \
  53     register __typeof (mem) _a0 asm ("a0") = _mem;                      \
  54     register __typeof (oldval) _d0 asm ("d0") = _oldval;                \
  55     register __typeof (newval) _d1 asm ("d1") = _newval;                \
  56     void *tmp;                                                          \
  57                                                                         \
  58     asm ("movel #_GLOBAL_OFFSET_TABLE_@GOTPC, %2\n\t"                   \
  59          "lea (-6, %%pc, %2), %2\n\t"                                   \
  60          "movel " STR_M68K_VDSO_SYMBOL (__vdso_atomic_cmpxchg_32)       \
  61          "@GOT(%2), %2\n\t"                                             \
  62          "movel (%2), %2\n\t"                                           \
  63          "jsr (%2)\n\t"                                                 \
  64          : "+d" (_d0), "+m" (*_a0), "=&a" (tmp)                         \
  65          : "a" (_a0), "d" (_d1));                                       \
  66     _d0;                                                                \
  67   })
  68 #else
  69 # define atomic_compare_and_exchange_val_acq(mem, newval, oldval)       \
  70   ({                                                                    \
  71     /* Use temporary variables to workaround call-clobberness of        \
  72        the registers.  */                                               \
  73     __typeof (mem) _mem = mem;                                          \
  74     __typeof (oldval) _oldval = oldval;                                 \
  75     __typeof (newval) _newval = newval;                                 \
  76     register __typeof (oldval) _d0 asm ("d0")                           \
  77       = (__typeof (oldval)) SYS_ify (atomic_cmpxchg_32);                \
  78     register __typeof (mem) _a0 asm ("a0") = _mem;                      \
  79     register __typeof (oldval) _d2 asm ("d2") = _oldval;                \
  80     register __typeof (newval) _d1 asm ("d1") = _newval;                \
  81                                                                         \
  82     asm ("trap #0"                                                      \
  83          : "+d" (_d0), "+m" (*_a0)                                      \
  84          : "a" (_a0), "d" (_d2), "d" (_d1));                            \
  85     _d0;                                                                \
  86   })
  87 #endif
  88
  89 #ifdef SHARED
  90 # define atomic_full_barrier()                                   \
  91   ({                                                             \
  92     void *tmp;                                                   \
  93                                                                  \
  94     asm ("movel #_GLOBAL_OFFSET_TABLE_@GOTPC, %0\n\t"            \
  95          "lea (-6, %pc, %0), %0\n\t"                             \
  96          "movel " STR_M68K_VDSO_SYMBOL (__vdso_atomic_barrier)   \
  97          "@GOT(%0), %0\n\t"                                      \
  98          "movel (%0), %0\n\t"                                    \
  99          "jsr (%0)\n\t"                                          \
 100          : "=&a" (tmp));                                         \
 101   })
 102 #else
 103 # define atomic_full_barrier()                          \
 104   (INTERNAL_SYSCALL (atomic_barrier, , 0), (void) 0)
 105 #endif
 106
 107 #endif