lib/librte_eal/arm/rte_cycles.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2015 Cavium, Inc
   3  */
   4
   5 #include "eal_private.h"
   6 #include "rte_cycles.h"
   7
   8 uint64_t
   9 get_tsc_freq_arch(void)
  10 {
  11 #if defined RTE_ARCH_ARM64 && !defined RTE_ARM_EAL_RDTSC_USE_PMU
  12         return __rte_arm64_cntfrq();
  13 #elif defined RTE_ARCH_ARM64 && defined RTE_ARM_EAL_RDTSC_USE_PMU
  14 #define CYC_PER_1MHZ 1E6
  15         /* Use the generic counter ticks to calculate the PMU
  16          * cycle frequency.
  17          */
  18         uint64_t ticks;
  19         uint64_t start_ticks, cur_ticks;
  20         uint64_t start_pmu_cycles, end_pmu_cycles;
  21
  22         /* Number of ticks for 1/10 second */
  23         ticks = __rte_arm64_cntfrq() / 10;
  24
  25         start_ticks = __rte_arm64_cntvct_precise();
  26         start_pmu_cycles = rte_rdtsc_precise();
  27         do {
  28                 cur_ticks = __rte_arm64_cntvct();
  29         } while ((cur_ticks - start_ticks) < ticks);
  30         end_pmu_cycles = rte_rdtsc_precise();
  31
  32         /* Adjust the cycles to next 1Mhz */
  33         return RTE_ALIGN_MUL_CEIL(end_pmu_cycles - start_pmu_cycles,
  34                         CYC_PER_1MHZ) * 10;
  35 #else
  36         return 0;
  37 #endif
  38 }