Developer’s guide for NetFPGA 2.1

In our project we used the NetFPGA 2.1 package, and found from README of the home directory, here is a developer’s guide for how you add the new design.

| Author: Jad Naous <first initial last name at stanford period edu>
| Description: Quick intro to NetFPGA

1.0 Tree structure
2.0 Getting started with design
2.1 Using modules
2.2 Adding your own code
2.3 Overriding library code
2.4 Coregen
3.0 Environment setup
4.0 Simulation
5.0 Implementation
6.0 Running the hardware
6.1 Kernel Driver
6.2 Download
7.0 Contacts

| 1.0 Tree structure

The tree is structured as follows:

+—— bin (contains scripts for running simulations
|            and setting up the environment)
+—— lib (contains stable modules and common parts
|       |    that are needed for simulation/synthesis/design)
|       |
|       +—- C (contains common software and code for reference designs)
|       |
|       +—- verilog (contains modules and files that can be reused for design)
|       |
|       +—- Makefiles (various makefiles for simulation and synthesis)
|       |
|       +—- Perl5 (contains common libraries to interact with
|                    reference designs and aid in simulation)
+—— projects (contains user projects including the reference designs)
+—- reference_nic
|       |
|       +—- src (contains all the verilog code to be used for
|       |          synthesis and simulation)
|       |
|       +—- synth (contains user .xco files to generate cores
|       |            and Makefile to implement the design)
|       |
|       +—- sw (contains all software parts for the project)
|       |
|       +—- include (contains files that define macros and other
|                files to be included for simulation and/or synthesis)
+—- reference_router (reference 4-port IPv4 router)
+—- CPCI2.1 (code for the Spartan device)

The tree was design to enable modularity and common code sharing between the
library and the user projects.

The scripts used for synthesis and simulation should be flexible enough to
allow the user to add her own code without changing or understanding how the
scripts work. But this is outside the scope of this README.

| 2.0 Getting started with Design
The best way to learn how to use the tree is by example. If you look at
the reference_nic project, you will notice several things:
1- The src directory is empty: This is because the project only uses
library modules.
2- The sw directory is empty: This is because the software for the
switch is also in the library
3- There is one file under include: lib_modules.txt. This file specifies the
library modules to use.

The best way to start a design is by copying either the reference_switch or the
reference_router directories and adding/modifying files in the new directory.


The lib_modules.txt file specifies a list of modules to use from the library.
The modules are specified relative to the NetFPGA2.1-x.y/lib/verilog directory.
You can choose to use different modules simply by changing the module path in
the lib_modules.txt file.


To add your own code, write the verilog files and put them in the src directory.
You can also choose to partition them into separate directories under src. Note
that only one level of hierarchy is usable.

You can choose to use some, all, or even none of the original library modules.
You can copy the library code and modify it in your project directory. Take out
the library modules you are not using from the lib_modules.txt file.


You might decide that you only need to change one file of a library module. You
don’t need to copy all the sources and remove the library module from
lib_modules.txt. Simply copy the file you wish to modify to your project’s src
directory and modify it there.


If you need to use IP cores generated with Xilinx’s Coregen, copy the .xco file
that was generated to your project’s synth directory. You don’t need any of the
other files. The scripts will take care of it.

| 3.0 Environment setup
The following environment variables need to be set:

NF_ROOT – set to the root directory of the tree (NetFPGA2.1-x.y)
NF_DESIGN_DIR – set to the project’s directory
(e.g. $NF_ROOT/projects/reference_nic)
NF_WORK_DIR – set to the working directory (somewhere with lots of space)

If you are running BASH you will then need to source
${NF_ROOT}/lib/bin/nf_profile. Otherwise, if you are running CSH then
you will need to source ${NF_ROOT}/lib/bin/nf_cshrc.

NOTE: Please make sure that the settings in these two files correspond
to your setup. THE DEFAULTS WILL *NOT* WORK!

| 4.0 Simulation

To simulate your design, there are several libraries to help. Take a look
at reference_router/verif/test_router_full to see how to use the perl
library functions. To create your own testbench, copy one of the test_*
directories and make sure its name has 3 parts test_major_minor. You
can then modify the make_pkts file to your liking.

The Perl libraries used live in lib/Perl5. You can add your own libraries
your project’s verif/src dir.

To run the simulation, use the following command: –major x –minor y

To run it with a gui, add the –gui switch. Type –help
for full details.

NOTE: coregen needs X. Make sure that you are running from a graphical
console if IP cores are being built (for example the first time you are
simulating or implementing a design.)

| 5.0 Implementation

To implement your design, cd to the synth directory and type make. If all
goes well, you should end up with nf2_top_par.bit file that you can use
to download to the FPGA.

If problems occur, make sure that you have all the .xco files for the user
generated IP cores in the synth directory. Make sure to look at nf2_top_par.twr
to make sure that your design has passed timing checks. Also make sure to
heed the note in section 4.0 above.

| 6.0 Running the hardware

To run the hardware, there are two steps:
1- load the kernel module
2- download the .bin file

1- cd to the lib/C/kernel directory, and type make.
2- as root, type insmod nf2.ko

If all goes well, you should see nf2c0, nf2c1, nf2c2, and nf2c3 when you do
ifconfig -a. If not, check that the card is plugged in properly and see if
it is identified by the lspci command.

1- cd to lib/C/download and type make
2- as root, type nf_download /path/to/nf2_top_par.bin

That’s it! Your hardware is loaded on the device and should be working.
Browse through the tools under lib/C/switch, lib/C/router, and lib/C/tools
for tools to use to interact with real hardware.

| 7.0 Contacts

Public discussion forums:
Direct e-mail:  



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