zephyr/boards/posix/nrf52_bsim/time_machine.c

226 lines
5.0 KiB
C

/*
* Copyright (c) 2017-2018 Oticon A/S
*
* SPDX-License-Identifier: Apache-2.0
*/
#include "NRF_HW_model_top.h"
#include "NRF_HWLowL.h"
#include "bs_tracing.h"
#include "bs_types.h"
#include "bs_utils.h"
/* Note: All timers are relative to hw_time and NOT to 'now' */
extern bs_time_t timer_nrf_main_timer;
/* The events priorities are as in this list from top to bottom
* Priority being which timer executes first if several trigger at the same
* instant
*/
static enum {
NRF_HW_MAIN_TIMER = 0,
NUMBER_OF_TIMERS,
NONE
} next_timer_index = NONE;
static bs_time_t *Timer_list[NUMBER_OF_TIMERS] = {
&timer_nrf_main_timer,
};
static bs_time_t next_timer_time = TIME_NEVER;
/*
* Current absolute time of this device, as the device knows it.
* It is never reset:
*/
static bs_time_t now;
/* Current time the HW of this device things it is */
static bs_time_t hw_time;
/*
* Offset between the current absolute time of the device and the HW time
* That is, the absolute time when the HW_time got reset
*/
static bs_time_t hw_time_delta;
/* Last time we synchronized with the bsim PHY, in device abs time */
static bs_time_t last_bsim_phy_sync_time;
#define BSIM_DEFAULT_PHY_MAX_RESYNC_OFFSET 1000000
/* At least every second we will inform the simulator about our timing */
static bs_time_t max_resync_offset = BSIM_DEFAULT_PHY_MAX_RESYNC_OFFSET;
/**
* Set the maximum amount of time the device will spend without talking
* (synching) with the phy.
* This does not change the functional behavior of the Zephyr code or of the
* radio emulation, and it is only relevant if special test code running in the
* device interacts behind the scenes with other devices test code.
* Setting for example a value of 5ms will ensure that this device time
* will never be more than 5ms away from the phy. Setting it in all devices
* to 5ms would then ensure no device time is farther apart than 5ms from any
* other.
*
* Note that setting low values has a performance penalty.
*/
void tm_set_phy_max_resync_offset(bs_time_t offset_in_us)
{
max_resync_offset = offset_in_us;
}
/**
* Return the absolute current time (no HW model except the RADIO
* should look into this)
*/
bs_time_t tm_get_abs_time(void)
{
return now;
}
/**
* Return the current HW time
*/
bs_time_t tm_get_hw_time(void)
{
return hw_time;
}
bs_time_t posix_get_hw_cycle(void)
{
return tm_get_hw_time();
}
/**
* Reset the HW time
*/
static void tm_reset_hw_time(void)
{
hw_time = 0;
hw_time_delta = now;
if (now != 0) {
bs_trace_error_line("Reset not supposed to happen after "
"initialization\n");
}
}
/**
* Update the current hw_time value given the absolute time
*/
INLINE void tm_update_HW_time(void)
{
hw_time = now - hw_time_delta;
}
bs_time_t tm_get_hw_time_from_abs_time(bs_time_t abstime)
{
if (abstime == TIME_NEVER) {
return TIME_NEVER;
}
return abstime - hw_time_delta;
}
/*
* Reset the HW time
*/
void tm_reset_hw_times(void)
{
tm_reset_hw_time();
}
/**
* Advance the internal time values of this device until time
*/
static void tm_sleep_until_abs_time(bs_time_t time)
{
if (time >= now) {
/*
* Ensure that at least we sync with the phy
* every max_resync_offset
*/
if (time > last_bsim_phy_sync_time + max_resync_offset) {
hwll_sync_time_with_phy(time);
last_bsim_phy_sync_time = time;
}
now = time;
} else {
/* LCOV_EXCL_START */
bs_trace_warning_manual_time_line(now, "next_time_time "
"corrupted (%"PRItime"<= %"PRItime", timer idx=%i)\n",
time, now, next_timer_index);
/* LCOV_EXCL_STOP */
}
tm_update_HW_time();
}
/**
* Keep track of the last time we synchronized the time with the scheduler
*/
void tm_update_last_phy_sync_time(bs_time_t abs_time)
{
last_bsim_phy_sync_time = abs_time;
}
/**
* Advance the internal time values of this device
* until the HW time reaches hw_time
*/
static void tm_sleep_until_hw_time(bs_time_t hw_time)
{
bs_time_t next_time = TIME_NEVER;
if (hw_time != TIME_NEVER) {
next_time = hw_time + hw_time_delta;
}
tm_sleep_until_abs_time(next_time);
}
/**
* Look into all timers and update next_timer accordingly
* To be called each time a "timed process" updates its timer
*/
void tm_find_next_timer_to_trigger(void)
{
next_timer_time = *Timer_list[0];
next_timer_index = 0;
for (uint i = 1; i < NUMBER_OF_TIMERS ; i++) {
if (next_timer_time > *Timer_list[i]) {
next_timer_time = *Timer_list[i];
next_timer_index = i;
}
}
}
bs_time_t tm_get_next_timer_abstime(void)
{
return next_timer_time + hw_time_delta;
}
bs_time_t tm_hw_time_to_abs_time(bs_time_t hwtime)
{
return hwtime + hw_time_delta;
}
bs_time_t tm_abs_time_to_hw_time(bs_time_t abstime)
{
return abstime - hw_time_delta;
}
/**
* Run ahead: Run the HW models and advance time as needed
* Note that this function does not return
*/
void tm_run_forever(void)
{
while (1) {
tm_sleep_until_hw_time(next_timer_time);
switch (next_timer_index) {
case NRF_HW_MAIN_TIMER:
nrf_hw_some_timer_reached();
break;
default:
bs_trace_error_time_line("next_timer_index "
"corrupted\n");
break;
}
tm_find_next_timer_to_trigger();
}
}