This is mostly important on ESP32 ECO3 with the ESP32_ECO3_CACHE_LOCK_FIX, because when we stall the other CPU core before we disable the TG1 WDT then the first CPU can get stuck in WDT ISR handle_livelock_int routine waiting for the other CPU.
System Notes
Timekeeping
The following are the timekeeping mechanisms available and their differences:
- System time (
esp_system_get_time
)
Time with the origin at g_startup_time
. The implementation is not handled by esp_system
,
but it does provide a default implementation using RTC timer. Currently, esp_timer
provides system time, since the hardware timers are under the control of that
component. However, no matter the underlying timer, the system time provider
should maintain the definition of having the origin point at g_startup_time
.
esp_timer
time (esp_timer_get_time
)
This is the time read from an underlying hardware timer, controlled through config. Origin is at the point where the underlying timer starts counting.
newlib
time (gettimeofday
)
Timekeeping function in standard library. Can be set (settimeofday
) or moved forward/backward (adjtime
);
with the possibility of the changes being made persistent through config.
Currently implemented in terms of system time, as the point of origin is fixed.
If persistence is enabled, RTC time is also used in conjuction with system time.
- RTC time (
esp_rtc_get_time_us
)
Time read from RTC timer.