eal/armv8: implement arch-specific TSC freq query

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).

Signed-off-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Jianbo Liu <jianbo.liu@linaro.org>
This commit is contained in:
Jerin Jacob 2017-09-22 13:55:36 +05:30 committed by Thomas Monjalon
parent 3dbc565e81
commit 583152bc81

View File

@ -1,7 +1,45 @@
/*
* BSD LICENSE
*
* Copyright (C) Cavium, Inc. 2015.
*
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* modification, are permitted provided that the following conditions
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#include "eal_private.h"
uint64_t
get_tsc_freq_arch(void)
{
#if defined RTE_ARCH_ARM64 && !defined RTE_ARM_EAL_RDTSC_USE_PMU
uint64_t freq;
asm volatile("mrs %0, cntfrq_el0" : "=r" (freq));
return freq;
#else
return 0;
#endif
}