can we track imx6 solo lite low power modes?

[danmez]

We have an application, which depends on low power usage, that we are porting to imx6 solo lite board.  Is there a simple way to track when it goes to one of the low power modes, such as connect a scope to pins?  When the linux kernel has daemons and our application running, it would be helpful to observe when the hardware goes to power saving modes and how quickly it it can come back when events occur.  Any suggestions on how to do this would be appreciated.

[AnsonHuang · Accepted solution]

Hi, Danmez

     I think you can monitor the MMDC or AXI's clock to get the low power mode, in runtime mode the MMDC's clock should be changing among 400M/100M/24M/1M accoding the usecase. To monitor the MMDC's clock, you can output it to CKO pin, please check the CCM_CCOSR to get how to config the MMDC clock output to your board and monitor it. This is for runtime mode, for suspend, you can just monitor the PMIC_VSTBY_REQ pin, if it is high, system is in DSM mode.