symbols and beats, quick clarification needed

you mean using 3 sgdmas? it's a waste of area, and if you do so a 192 bit data will be split into 3 parts stored in different areas of your memory.

I think you can use a data_format_adaptor:

64 bitpersym * 3 symperbeat => data_format_adaptor => 64 bitpersym * 1 symperbeat => sgdam with 64-bit data width.