arch/metag/include/asm/cmpxchg_lock1.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __ASM_METAG_CMPXCHG_LOCK1_H
   3 #define __ASM_METAG_CMPXCHG_LOCK1_H
   4
   5 #include <asm/global_lock.h>
   6
   7 /* Use LOCK2 as these have to be atomic w.r.t. ordinary accesses. */
   8
   9 static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
  10 {
  11         unsigned long flags, retval;
  12
  13         __global_lock2(flags);
  14         fence();
  15         retval = *m;
  16         *m = val;
  17         __global_unlock2(flags);
  18         return retval;
  19 }
  20
  21 static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
  22 {
  23         unsigned long flags, retval;
  24
  25         __global_lock2(flags);
  26         fence();
  27         retval = *m;
  28         *m = val & 0xff;
  29         __global_unlock2(flags);
  30         return retval;
  31 }
  32
  33 static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
  34                                           unsigned long new)
  35 {
  36         __u32 retval;
  37         unsigned long flags;
  38
  39         __global_lock2(flags);
  40         retval = *m;
  41         if (retval == old) {
  42                 fence();
  43                 *m = new;
  44         }
  45         __global_unlock2(flags);
  46         return retval;
  47 }
  48
  49 #endif /* __ASM_METAG_CMPXCHG_LOCK1_H */