kernel/arch/microblaze/include/asm/cmpxchg.h

   1 #ifndef _ASM_MICROBLAZE_CMPXCHG_H
   2 #define _ASM_MICROBLAZE_CMPXCHG_H
   3
   4 #include <linux/irqflags.h>
   5
   6 void __bad_xchg(volatile void *ptr, int size);
   7
   8 static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
   9                                                                 int size)
  10 {
  11         unsigned long ret;
  12         unsigned long flags;
  13
  14         switch (size) {
  15         case 1:
  16                 local_irq_save(flags);
  17                 ret = *(volatile unsigned char *)ptr;
  18                 *(volatile unsigned char *)ptr = x;
  19                 local_irq_restore(flags);
  20                 break;
  21
  22         case 4:
  23                 local_irq_save(flags);
  24                 ret = *(volatile unsigned long *)ptr;
  25                 *(volatile unsigned long *)ptr = x;
  26                 local_irq_restore(flags);
  27                 break;
  28         default:
  29                 __bad_xchg(ptr, size), ret = 0;
  30                 break;
  31         }
  32
  33         return ret;
  34 }
  35
  36 #define xchg(ptr, x) \
  37         ((__typeof__(*(ptr))) __xchg((unsigned long)(x), (ptr), sizeof(*(ptr))))
  38
  39 #include <asm-generic/cmpxchg.h>
  40 #include <asm-generic/cmpxchg-local.h>
  41
  42 #endif /* _ASM_MICROBLAZE_CMPXCHG_H */