Network-on-Chip (NoCs) have been widely accepted as the interconnection
choice for Chip MultiProcessor (CMP) and MultiProcessor System-on-Chip
(MPSoCs). In this sense, current CMPs or MPSoCs rely on simple NoC
designs based on rings or meshes. As the number of cores to interconnect
grows, simple NoCs are not able to fulfil system requirements, that is, low
latency and high throughput. In this sense, more complex NoC solutions
have been proposed and analyzed. However, complex designs means complex
implementations – specially critical is link length – which makes these solutions
costly or even unaffordable.

In this dissertation, we present a floorplan-aware NoC design methodology
that minimizes the implementation drawbacks of complex NoC designs, that
is, high-radix switches and long links. As a first step, we redesign the switch
by making it modular and locally self contained. That is, each small block has
its own buffering, arbitration, and crossing capabilities. As a second step, we
flexibilize the placement of the basic modules, allowing a distribution of the
switch basic blocs all over the chip.

We have applied our floorplan-aware NoC design into different scenarios.
First, we show that it is possible to build a conventional NoC as a 2D mesh
by using a floorplan-aware switch. Results show that modularizing and distributing
the switch along the link reduces the network critical path and power
consumption over conventional implementations. Additionally, these benefits
increase as the switch radix increases, and hence, our floorplan-aware switch
fits perfectly in complex NoC implementations, as the flattened butterfly or
concentrated meshes.

Second, we have leveraged our floorplan-aware NoC design methodology to implement a distributed crossbar. Our distributed crossbar clearly outperforms
in terms of latency and throughput the rest of configurations. For very
large networks, our crossbar resources requirements could be unaffordable. In
this case, a hierarchical approach has been implemented which almost keeps
all the crossbar benefits but reducing resources used.