Use cntvct_el0 system register to get the system counter frequency.

If the system is configured with RTE_ARM_EAL_RDTSC_USE_PMU then
return 0(let the common code calibrate the tsc frequency).

CC: Jianbo Liu <redacted>
Signed-off-by: Jerin Jacob <redacted>
---
 .../common/include/arch/arm/rte_cycles_64.h        | 30 ++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h b/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h
index 154576910..5b95cb67d 100644
--- a/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h
+++ b/lib/librte_eal/common/include/arch/arm/rte_cycles_64.h

@@ -58,6 +58,23 @@ rte_rdtsc(void)
        asm volatile("mrs %0, cntvct_el0" : "=r" (tsc));
        return tsc;
 }
+
+/**
+ * Get the number of rdtsc cycles in one second if the architecture supports.
+ *
+ * @return
+ *   The number of rdtsc cycles in one second. Return zero if the architecture
+ *   support is not available.
+ */
+static inline uint64_t
+rte_rdtsc_arch_hz(void)
+{
+       uint64_t freq;
+
+       asm volatile("mrs %0, cntfrq_el0" : "=r" (freq));
+       return freq;
+}
+
 #else
 /**
  * This is an alternative method to enable rte_rdtsc() with high resolution

@@ -85,6 +102,19 @@ rte_rdtsc(void)
        asm volatile("mrs %0, pmccntr_el0" : "=r"(tsc));
        return tsc;
 }
+
+/**
+ * Get the number of rdtsc cycles in one second if the architecture supports.
+ *
+ * @return
+ *   The number of rdtsc cycles in one second. Return zero if the architecture
+ *   support is not available.
+ */
+static inline uint64_t
+rte_rdtsc_arch_hz(void)
+{
+       return 0;
+}
 #endif

 static inline uint64_t
--

2.14.0