include/asm-powerpc/timex.h

   1 #ifndef _ASM_POWERPC_TIMEX_H
   2 #define _ASM_POWERPC_TIMEX_H
   3
   4 #ifdef __KERNEL__
   5
   6 /*
   7  * PowerPC architecture timex specifications
   8  */
   9
  10 #include <linux/config.h>
  11 #include <asm/cputable.h>
  12
  13 #define CLOCK_TICK_RATE 1024000 /* Underlying HZ */
  14
  15 typedef unsigned long cycles_t;
  16
  17 static inline cycles_t get_cycles(void)
  18 {
  19         cycles_t ret;
  20
  21 #ifdef __powerpc64__
  22
  23         __asm__ __volatile__("mftb %0" : "=r" (ret) : );
  24
  25 #else
  26         /*
  27          * For the "cycle" counter we use the timebase lower half.
  28          * Currently only used on SMP.
  29          */
  30
  31         ret = 0;
  32
  33         __asm__ __volatile__(
  34                 "98:    mftb %0\n"
  35                 "99:\n"
  36                 ".section __ftr_fixup,\"a\"\n"
  37                 "       .long %1\n"
  38                 "       .long 0\n"
  39                 "       .long 98b\n"
  40                 "       .long 99b\n"
  41                 ".previous"
  42                 : "=r" (ret) : "i" (CPU_FTR_601));
  43 #endif
  44
  45         return ret;
  46 }
  47
  48 #endif  /* __KERNEL__ */
  49 #endif  /* _ASM_POWERPC_TIMEX_H */