AnsweredAssumed Answered

FreeRTOS in tickless mode and LLS3

Question asked by Eugene Hiihtaja on Aug 6, 2018
Latest reply on Aug 23, 2018 by Kerry Zhou

Hi !


I have taken FreeRTOS example from SDK and configure it in tickless mode where Systick timer only is used as clock source. 

Everything works fine in tick and tickless configurations.


After that I have put MCU to LLS3 low power mode and wakeup it to RUN mode back be using external LLWU enabled GPIO pin. Typical LLWU clean up is executed ( in interrupt handler ) and PLL lock ( MGC in PEE mode) are executed

as first code after wake up.


/* Wait for PLL lock. MCG in PEE mode in RUN. */
while (!(kMCG_Pll0LockFlag & CLOCK_GetStatusFlags()))




Everything works fine in RTOS use Systick and tickless mode is disabled.


But in tickless mode, systick timer is not recovered and task scheduler dosn't work any more.

ApplicationTickHook() is not called anymore and execution is not continued.


Can it be so that fsl_tickless_systick.c is implemented in way what block LLS3 recovering some how ?

It is just not taken in account  ?


Can you suggest what fix need to be done if RTOS can continue execution after LLS3 in Tickless mode ?