Description

I created this issue to provide a central place for the similar/overlapping discussions started in #8401 and #7787 and to move to make the discussion about the actual pm concept in RIOT instead of having the general discussion in those specific, STM related PRs.

I see the main goal in this issue to find out where (or why) the actual pm concept is 'totally useless', and to see if we either need to re-think the hole thing or what needs to fixed/added, or if this is just a matter of clarification.

So why is pm not usable and which specific use cases does it prevent from working? Keep in mind to separate between missing implementations (no pm mode blocking in periph drivers, not 'disable/powerdown` functions in higher level modules like the shell) and broken concept(s).

References

#8401, #7787, #6802