arch/metag/include/asm/cmpxchg.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __ASM_METAG_CMPXCHG_H
   3 #define __ASM_METAG_CMPXCHG_H
   4
   5 #include <asm/barrier.h>
   6
   7 #if defined(CONFIG_METAG_ATOMICITY_IRQSOFF)
   8 #include <asm/cmpxchg_irq.h>
   9 #elif defined(CONFIG_METAG_ATOMICITY_LOCK1)
  10 #include <asm/cmpxchg_lock1.h>
  11 #elif defined(CONFIG_METAG_ATOMICITY_LNKGET)
  12 #include <asm/cmpxchg_lnkget.h>
  13 #endif
  14
  15 extern void __xchg_called_with_bad_pointer(void);
  16
  17 #define __xchg(ptr, x, size)                            \
  18 ({                                                      \
  19         unsigned long __xchg__res;                      \
  20         volatile void *__xchg_ptr = (ptr);              \
  21         switch (size) {                                 \
  22         case 4:                                         \
  23                 __xchg__res = xchg_u32(__xchg_ptr, x);  \
  24                 break;                                  \
  25         case 1:                                         \
  26                 __xchg__res = xchg_u8(__xchg_ptr, x);   \
  27                 break;                                  \
  28         default:                                        \
  29                 __xchg_called_with_bad_pointer();       \
  30                 __xchg__res = x;                        \
  31                 break;                                  \
  32         }                                               \
  33                                                         \
  34         __xchg__res;                                    \
  35 })
  36
  37 #define xchg(ptr, x)    \
  38         ((__typeof__(*(ptr)))__xchg((ptr), (unsigned long)(x), sizeof(*(ptr))))
  39
  40 /* This function doesn't exist, so you'll get a linker error
  41  * if something tries to do an invalid cmpxchg(). */
  42 extern void __cmpxchg_called_with_bad_pointer(void);
  43
  44 static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
  45                                       unsigned long new, int size)
  46 {
  47         switch (size) {
  48         case 4:
  49                 return __cmpxchg_u32(ptr, old, new);
  50         }
  51         __cmpxchg_called_with_bad_pointer();
  52         return old;
  53 }
  54
  55 #define cmpxchg(ptr, o, n)                                              \
  56         ({                                                              \
  57                 __typeof__(*(ptr)) _o_ = (o);                           \
  58                 __typeof__(*(ptr)) _n_ = (n);                           \
  59                 (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \
  60                                                (unsigned long)_n_,      \
  61                                                sizeof(*(ptr)));         \
  62         })
  63
  64 #endif /* __ASM_METAG_CMPXCHG_H */