TOGA is generally a 5 minutes limitation.
If you are not taking off or going around, max power is "MCT" max continuous.
MCT - as long as you want...
One limitation I once came accross to, is "ACCELERATION" - 2 minutes limit.
Read your manuals, if nothing specified, I would say the above applies.
xxx
So technically, TOGA could not be used in cruise.
Except maybe in emergency - i.e. stall recovery.
xxx
Happy contrails