Description
Design Problem:
For FPGA, based on the references on VLSI Array Processors, design in Xilinx
Model Composer, a hardware accelerator block to perform 4 x 4 matrix
multiplication.
FPGA Architecture: This should be a two-dimensional square structure with 16 processor
elements that essentially do multiply and accumulate. You should design this as a square
array, with some control signals to load, compute, and unload the array.
FPGA Data Format: You can assume simple data types, such as 16-bit two’s complement
fixed-point numbers. The data generation on Matlab or Simulink can be a simple function
to either build the matrix or build individual vectors. You can assume a simple all integer
data format, that is no fractional part, to make data generation easier.
FPGA Control: The goals are to handle the array structures and to include the associated
delay elements for proper dataflow and timing. This array should interface with Simulink to
provide data to the array and then unload it. The array should be able to be triggered
multiple times and the array should be able to compute more than one 4 x 4 matrix
computation. That is, you should be able to pipeline multiple matrix multiplications with as
little delay as possible to load data and unload results. The array should also have a
Matrix-Vector mode that can be controlled by an external signal. This will allow us to use
the array for both matrix-matrix multiplication and then later in the semester for matrixvector multiplication in the linear system solver project.
FPGA Data Loading/Unloading: The input data should be loaded in a systolic manner
into the rows and columns of the array. The Model Composer Gateways would be at the
boundary of the matrix multiplication array. The data generation should not be part of the
Xilinx block of the Model Composer model. Instead, the data should be generated in
Matlab into the workspace or with basic Simulink blocks running on the host PC. Several
unloading schemes were suggested. Choose a method that you believe will be most
efficient. Avoid using the “RAM” addressing model that was mentioned in lecture as not
easily scalable. Your design should not use large multiplexors for data loading and
unloading, since multiplexors can be slow and are not part of the systolic design flow.
Please note that the Zynq chip on the ZedBoard only has 200 available I/O pins for
gateways and that a few will be used for timing and control by Model Composer. Each I/O
bit uses a gateway which is then one physical I/O pin on the Zynq chip. Remember that a
16 bit input data element will use 16 I/O pins. So, plan your I/O with this constraint in mind.
FPGA Testing: Please create the Model Composer block diagram using adder, multiplier,
and delay blocks and gateways. You may use other blocks for data generation in the
purely Simulink/Matlab non-Model Composer part. Then simulate, implement and describe
the resource utilization and the maximum clock rate and slack time for performing this
matrix multiplication accelerator kernel. You would need to first use the HDL Netlist
generation for our Zynq chip and Vivado to have the place and route implementation
reports for only your core array modules excluding the ARM core support logic as in the
Project 1 timing and resource utilization tutorial steps. After collecting resource utilization,
then target for JTAG HW-Cosim on the ZedBoard for generation, download and run the
resulting bit file, to verify hardware in the loop simulation on the ZedBoard using the
hardware co-sim feature.
FPGA Files and Documentation: Please upload your design and report to Canvas. This
should be a single zip file that contains your design files, the .slx Model Composer and any
.m Matlab files along with a report. Include the Powerpoint file that you presented in class.
The report should contain a description of your design approach, your tradeoff on input
and output architecture, screen shots of your model files, and simulation and hardware cosimulation screen shot results. You should include your resource utilization and timing
information from the testing phase. Also, you should describe the scalability of your
design, the ability to pipeline a series of matrix multiplications on your array and the
latency and delay characteristics. You should also describe your testing methodology so
that we can build and run your design in simulation and on hardware.
Presentation: The purpose of the presentation is to describe your architecture decisions
and to present resource utilization and maximum clock frequency and pipelining potential.
There should be a maximum of 3 Powerpoint slides and 5 minutes with questions. Please
email the Powerpoint to cavallar@rice.edu by noon on 29 September at the latest, so that
they can be pre-loaded on the lab computer to save time switching files.
