iMX7D A7 and M4 both in STOP mode not working

[kunjalgarach]

I am working on iMX7D Soc power management. My product is battery operated and require efficient power management.

Let's say, initially I keep both - A7 and M4 is in RUN mode. M4 side i configured external interrupt as wake up source.  

Keeping A7 operating in RUN mode, I put M4 core in STOP mode to observe the effect.

I have observed that putting M4 in STOP mode also puts A7 in STOP mode automatically.

If I give external interrupt trigger to M4, it will pull M4 out of STOP mode. In interrupt handler routine if I make M4 to RUN mode then A7 also start responding.

Why I am observing this type of behavior? 

Why putting M4 in STOP mode, A7 stops responding?

Kunjal

[CarlosCasillas]

Hi Kunjal,

Have you ensured which clock source are using each core? Have you configured the Resource Domain Controller? Also, have you verified from which memory is each core running in order to ensure that the memory will be still available for the not-stopped core?

You could also take a look at Application Note AN5317 for additional reference.

Hope this will be useful for you.
Best regards!
/Carlos
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------