The files for class 3 are may be found in SOCDAM /toyclasses/class3.
This includes an abstract ISS for a really trivial microprocessor called nominalproc as well as a concrete ISS and an RTL-style bus initiator in SystemC.
Some simple IP blocks (address decoder and response mux) for building a tree-structure can be examined.
Exercises: using the RTL-style blocks provided, please experiment with various configurations and understand how you would make a more-complex system using more of the addr_decode and busmux components to address the components.