Deepsleep is entered with a call to CySysPmDeepSleep(). Of more interest is the question "How to get out of Deeo Sleep". Have a look into the "System Reference Guide" which you find in Creator from Help-menu.
These might help -
PSoC Creator 101 PSoC 4 Low Power Mode Videos:
http://www.cypress.com/?rID=110007 AN92584 - Designing for Low Power and Estimating Battery Life for BLE Applications