This problem will be seen in the Intel® Quartus® Prime Software when accessing the Avalon® Memory-Mapped Agent Interface for CSR and Avalon® Memory-Mapped Agent Interface for Memory Access ports at the same time in Generic Serial Flash Interface Intel® FPGA IP.
Both ports must be accessed at different times.
There is no workaround. You are advised to access the two ports separately.
For more information, refer to the Generic Serial Flash Interface Intel® FPGA IP User Guide - Signals.