zephyr/arch/x86/timing.c

92 lines
1.7 KiB
C

/*
* Copyright (c) 2020 Intel Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/arch/x86/arch.h>
#include <zephyr/kernel.h>
#include <zephyr/sys_clock.h>
#include <zephyr/timing/timing.h>
#include <zephyr/app_memory/app_memdomain.h>
K_APP_BMEM(z_libc_partition) static uint64_t tsc_freq;
void arch_timing_x86_init(void)
{
uint32_t cyc_start, cyc_end;
uint64_t tsc_start, tsc_end;
uint64_t cyc_freq = sys_clock_hw_cycles_per_sec();
uint64_t dcyc, dtsc;
do {
cyc_start = k_cycle_get_32();
tsc_start = z_tsc_read();
k_busy_wait(10 * USEC_PER_MSEC);
cyc_end = k_cycle_get_32();
tsc_end = z_tsc_read();
/*
* cycles are in 32-bit, and delta must be
* calculated in 32-bit precision. Or it would be
* wrapping around in 64-bit.
*/
dcyc = (uint32_t)cyc_end - (uint32_t)cyc_start;
dtsc = tsc_end - tsc_start;
} while ((dcyc == 0) || (dtsc == 0));
tsc_freq = (cyc_freq * dtsc) / dcyc;
}
uint64_t arch_timing_x86_freq_get(void)
{
return tsc_freq;
}
void arch_timing_init(void)
{
arch_timing_x86_init();
}
void arch_timing_start(void)
{
}
void arch_timing_stop(void)
{
}
timing_t arch_timing_counter_get(void)
{
return z_tsc_read();
}
uint64_t arch_timing_cycles_get(volatile timing_t *const start,
volatile timing_t *const end)
{
return (*end - *start);
}
uint64_t arch_timing_freq_get(void)
{
return arch_timing_x86_freq_get();
}
uint64_t arch_timing_cycles_to_ns(uint64_t cycles)
{
return ((cycles) * NSEC_PER_SEC / tsc_freq);
}
uint64_t arch_timing_cycles_to_ns_avg(uint64_t cycles, uint32_t count)
{
return arch_timing_cycles_to_ns(cycles) / count;
}
uint32_t arch_timing_freq_get_mhz(void)
{
return (uint32_t)(arch_timing_freq_get() / 1000000U);
}