MCU-PLUS-SDK-AM243X: PCIe access exception handling

Tool/software:

Hi Ti expert,

       I am using AM243X EVM board as RC to access FPGA EP.

       For exception handling, I carry out the following tests.

                 1 Cross border access -- I read an address that out of the range of EP' memory, the MCU crashed(The program jump to somewhere and stuck there).

                 2 Access while the EP is absent -- after initialization and RC can access EP, then power off the EP. If the RC access EP then, the MCU will crash too.

        For Cross border access, I can check the address before access.

        My question for the second, How can RC know the EP is active before any access?

        Are there others failure should I to consider with my application code?

Thanks 

Chunyang