zephyr/boards/posix/nrf_bsim/cpu_wait.c

68 lines
1.9 KiB
C

/*
* Copyright (c) 2017 Oticon A/S
* Copyright (c) 2023 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdbool.h>
#include <stdint.h>
#include "fake_timer.h"
#include <zephyr/arch/posix/posix_soc_if.h>
#include <posix_board_if.h>
#include <posix_soc.h>
#include "nsi_hw_scheduler.h"
/**
* Replacement to the kernel k_busy_wait()
* Will block this thread (and therefore the whole Zephyr) during usec_to_wait
*
* Note that interrupts may be received in the meanwhile and that therefore this
* thread may lose context.
* Therefore the wait time may be considerably longer.
*
* All this function ensures is that it will return after usec_to_wait or later.
*/
void arch_busy_wait(uint32_t usec_to_wait)
{
bs_time_t time_end = nsi_hws_get_time() + usec_to_wait;
while (nsi_hws_get_time() < time_end) {
/*
* There may be wakes due to other interrupts or nested calls to
* k_busy_wait in interrupt handlers
*/
nhw_fake_timer_wake_in_time(CONFIG_NATIVE_SIMULATOR_MCU_N, time_end);
posix_halt_cpu();
}
}
/**
* Will block this thread (and therefore the whole Zephyr) during usec_to_waste
*
* Very similar to arch_busy_wait(), but if an interrupt or context switch
* occurs this function will continue waiting after, ensuring that
* usec_to_waste are spent in this context, irrespectively of how much more
* time would be spent on interrupt handling or possible switched-in tasks.
*
* Can be used to emulate code execution time.
*/
void posix_cpu_hold(uint32_t usec_to_waste)
{
bs_time_t time_start;
int64_t to_wait = usec_to_waste;
while (to_wait > 0) {
/*
* There may be wakes due to other interrupts or nested calls to
* cpu_hold in interrupt handlers
*/
time_start = nsi_hws_get_time();
nhw_fake_timer_wake_in_time(CONFIG_NATIVE_SIMULATOR_MCU_N, time_start + to_wait);
posix_change_cpu_state_and_wait(true);
to_wait -= nsi_hws_get_time() - time_start;
posix_irq_handler();
}
}