Once a BDC is added to or created within a top-level block design diagram, BDC
cannot be directly edited from the diagram of the top-level block design. All further
changes to the content of a block design container must happen within the source block
design of that BDC. The user has to open up the .bd source of BDC, make
changes (such as adding or removing IP blocks), validate the design, and save the source
block design.
Note: To change a BDC, double-click the BD
source in the Sources window. Alternatively,
right-click on the BDC instance in the top-level BD diagram and select Open Source. Once the BDC changes are synced, the output
products have to be generated on the top-level design, but not on the source block
BD.