hello john.mcinnis,
there’re two groups of GPIOs, Main and AON GPIOs. you may have each GPIO controller owned by different masters.
you may also refer to TRM.
please check [8.9 GPIO Controller] within [CHAPTER 8: MULTI-PURPOSE I/O PINS AND PIN MULTIPLEXING (PINMUXING)] for more details.
in addition,
here’s a discussion thread you may refer to, gpio interrupts from user space.
thanks