PCIe-AC5 card on Linux

We are migrating an old 16bit DOS process control application to Linux-RT. The old system uses two AC5 ISA cards but I want to replace with a single PCIe AC5 on Linux system. The application is written in C/C++. Has anyone had success with the PCIe AC5 card on Linux? Would the low level IO be the same as reading / writing to a serial port?

Thank you!