kernel/arch/h8300/include/asm/cmpxchg.h

   1 #ifndef __ARCH_H8300_CMPXCHG__
   2 #define __ARCH_H8300_CMPXCHG__
   3
   4 #include <linux/irqflags.h>
   5
   6 #define xchg(ptr, x) \
   7         ((__typeof__(*(ptr)))__xchg((unsigned long)(x), (ptr), \
   8                                     sizeof(*(ptr))))
   9
  10 struct __xchg_dummy { unsigned long a[100]; };
  11 #define __xg(x) ((volatile struct __xchg_dummy *)(x))
  12
  13 static inline unsigned long __xchg(unsigned long x,
  14                                    volatile void *ptr, int size)
  15 {
  16         unsigned long tmp, flags;
  17
  18         local_irq_save(flags);
  19
  20         switch (size) {
  21         case 1:
  22                 __asm__ __volatile__
  23                         ("mov.b %2,%0\n\t"
  24                          "mov.b %1,%2"
  25                          : "=&r" (tmp) : "r" (x), "m" (*__xg(ptr)));
  26                 break;
  27         case 2:
  28                 __asm__ __volatile__
  29                         ("mov.w %2,%0\n\t"
  30                          "mov.w %1,%2"
  31                          : "=&r" (tmp) : "r" (x), "m" (*__xg(ptr)));
  32                 break;
  33         case 4:
  34                 __asm__ __volatile__
  35                         ("mov.l %2,%0\n\t"
  36                          "mov.l %1,%2"
  37                          : "=&r" (tmp) : "r" (x), "m" (*__xg(ptr)));
  38                 break;
  39         default:
  40                 tmp = 0;
  41         }
  42         local_irq_restore(flags);
  43         return tmp;
  44 }
  45
  46 #include <asm-generic/cmpxchg-local.h>
  47
  48 /*
  49  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
  50  * them available.
  51  */
  52 #define cmpxchg_local(ptr, o, n)                                         \
  53         ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr),              \
  54                                                      (unsigned long)(o), \
  55                                                      (unsigned long)(n), \
  56                                                      sizeof(*(ptr))))
  57 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
  58
  59 #ifndef CONFIG_SMP
  60 #include <asm-generic/cmpxchg.h>
  61 #endif
  62
  63 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  64
  65 #endif /* __ARCH_H8300_CMPXCHG__ */