Hello,
Floorplanning is typically an interactive step but if you've scripted your floorplan creation you can specify the script in the setup.tcl file using:
set vars(fp_tcl_file) fileName
The Foundation Flow will then source the script during the init step. Alternatively, if you have it defined in a procedure you can set the variable:
set vars(fp_tcl_proc) procName
Lastly, there are prototyping Foundation Flows you can utilize to do your floorplanning. See the Rapid Adoption Kits available here:
http://support.cadence.com/wps/mypoc/cos?uri=deeplinkmin:DocumentViewer;src=wp;q=ProductInformation/Digital_IC_Design/ApplicationPackages/ICD_RAK_Home.htm
Hope this helps,
Brian