The cpuidle subsystem

What does the number in power field for each C state signify? for C0 its very high on my system. Its 4294967295 (mW). Is it the total power consumed in C0 till now? But seems like this value is not changing.

The second question is about the C-state transitions. Can a transition occur within the same state? I mean CPU goes into C3 from C3 only. Because the value for C3 usage is very high for my system. (AFAIK the usage number denotes the number of transitions to that state) So seems like the "enter" function is being called from C3 and again the output state is C3.