LXR linux/arch/openrisc/include/asm/atomic.h

   1/*
   2 * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
   3 *
   4 * This file is licensed under the terms of the GNU General Public License
   5 * version 2.  This program is licensed "as is" without any warranty of any
   6 * kind, whether express or implied.
   7 */
   8
   9#ifndef __ASM_OPENRISC_ATOMIC_H
  10#define __ASM_OPENRISC_ATOMIC_H
  11
  12#include <linux/types.h>
  13
  14/* Atomically perform op with v->counter and i */
  15#define ATOMIC_OP(op)                                                   \
  16static inline void arch_atomic_##op(int i, atomic_t *v)                 \
  17{                                                                       \
  18        int tmp;                                                        \
  19                                                                        \
  20        __asm__ __volatile__(                                           \
  21                "1:     l.lwa   %0,0(%1)        \n"                     \
  22                "       l." #op " %0,%0,%2      \n"                     \
  23                "       l.swa   0(%1),%0        \n"                     \
  24                "       l.bnf   1b              \n"                     \
  25                "        l.nop                  \n"                     \
  26                : "=&r"(tmp)                                            \
  27                : "r"(&v->counter), "r"(i)                              \
  28                : "cc", "memory");                                      \
  29}
  30
  31/* Atomically perform op with v->counter and i, return the result */
  32#define ATOMIC_OP_RETURN(op)                                            \
  33static inline int arch_atomic_##op##_return(int i, atomic_t *v)         \
  34{                                                                       \
  35        int tmp;                                                        \
  36                                                                        \
  37        __asm__ __volatile__(                                           \
  38                "1:     l.lwa   %0,0(%1)        \n"                     \
  39                "       l." #op " %0,%0,%2      \n"                     \
  40                "       l.swa   0(%1),%0        \n"                     \
  41                "       l.bnf   1b              \n"                     \
  42                "        l.nop                  \n"                     \
  43                : "=&r"(tmp)                                            \
  44                : "r"(&v->counter), "r"(i)                              \
  45                : "cc", "memory");                                      \
  46                                                                        \
  47        return tmp;                                                     \
  48}
  49
  50/* Atomically perform op with v->counter and i, return orig v->counter */
  51#define ATOMIC_FETCH_OP(op)                                             \
  52static inline int arch_atomic_fetch_##op(int i, atomic_t *v)            \
  53{                                                                       \
  54        int tmp, old;                                                   \
  55                                                                        \
  56        __asm__ __volatile__(                                           \
  57                "1:     l.lwa   %0,0(%2)        \n"                     \
  58                "       l." #op " %1,%0,%3      \n"                     \
  59                "       l.swa   0(%2),%1        \n"                     \
  60                "       l.bnf   1b              \n"                     \
  61                "        l.nop                  \n"                     \
  62                : "=&r"(old), "=&r"(tmp)                                \
  63                : "r"(&v->counter), "r"(i)                              \
  64                : "cc", "memory");                                      \
  65                                                                        \
  66        return old;                                                     \
  67}
  68
  69ATOMIC_OP_RETURN(add)
  70ATOMIC_OP_RETURN(sub)
  71
  72ATOMIC_FETCH_OP(add)
  73ATOMIC_FETCH_OP(sub)
  74ATOMIC_FETCH_OP(and)
  75ATOMIC_FETCH_OP(or)
  76ATOMIC_FETCH_OP(xor)
  77
  78ATOMIC_OP(add)
  79ATOMIC_OP(sub)
  80ATOMIC_OP(and)
  81ATOMIC_OP(or)
  82ATOMIC_OP(xor)
  83
  84#undef ATOMIC_FETCH_OP
  85#undef ATOMIC_OP_RETURN
  86#undef ATOMIC_OP
  87
  88#define arch_atomic_add_return  arch_atomic_add_return
  89#define arch_atomic_sub_return  arch_atomic_sub_return
  90#define arch_atomic_fetch_add   arch_atomic_fetch_add
  91#define arch_atomic_fetch_sub   arch_atomic_fetch_sub
  92#define arch_atomic_fetch_and   arch_atomic_fetch_and
  93#define arch_atomic_fetch_or    arch_atomic_fetch_or
  94#define arch_atomic_fetch_xor   arch_atomic_fetch_xor
  95#define arch_atomic_add         arch_atomic_add
  96#define arch_atomic_sub         arch_atomic_sub
  97#define arch_atomic_and         arch_atomic_and
  98#define arch_atomic_or          arch_atomic_or
  99#define arch_atomic_xor         arch_atomic_xor
 100
 101/*
 102 * Atomically add a to v->counter as long as v is not already u.
 103 * Returns the original value at v->counter.
 104 *
 105 * This is often used through atomic_inc_not_zero()
 106 */
 107static inline int arch_atomic_fetch_add_unless(atomic_t *v, int a, int u)
 108{
 109        int old, tmp;
 110
 111        __asm__ __volatile__(
 112                "1:     l.lwa %0, 0(%2)         \n"
 113                "       l.sfeq %0, %4           \n"
 114                "       l.bf 2f                 \n"
 115                "        l.add %1, %0, %3       \n"
 116                "       l.swa 0(%2), %1         \n"
 117                "       l.bnf 1b                \n"
 118                "        l.nop                  \n"
 119                "2:                             \n"
 120                : "=&r"(old), "=&r" (tmp)
 121                : "r"(&v->counter), "r"(a), "r"(u)
 122                : "cc", "memory");
 123
 124        return old;
 125}
 126#define arch_atomic_fetch_add_unless    arch_atomic_fetch_add_unless
 127
 128#define arch_atomic_read(v)             READ_ONCE((v)->counter)
 129#define arch_atomic_set(v,i)            WRITE_ONCE((v)->counter, (i))
 130
 131#include <asm/cmpxchg.h>
 132
 133#define arch_atomic_xchg(ptr, v)                (arch_xchg(&(ptr)->counter, (v)))
 134#define arch_atomic_cmpxchg(v, old, new)        (arch_cmpxchg(&((v)->counter), (old), (new)))
 135
 136#endif /* __ASM_OPENRISC_ATOMIC_H */
 137