A10 DDR4 Hard Controller AVMM Operation / Timing Diagram

The best way to get started is to generate the example design from the IP parameter editor based on your IP settings. Make sure to include the creation of the traffic generator to see an example of how you'd hook up your user logic to the controller.

As far as your data width is concerned, it's always best, if possible, to match your master interface's width to the width of the slave interface. That way, width adapter logic is not needed. So if the slave side is 128, a 128-bit master might be most efficient. However, if the master is narrower, logic will be added to automatically combine multiple accesses together.

Byte enables would really only be absolutely required with a narrower master performing writes to make sure the appropriate bytes are being written to. Other than that, byte enables would be handled automatically in the generated interconnect. Burst count is used if you plan on locking the master to the slave for multiple read/write commands in sequence.