Odin II

Odin II is used for logic synthesis and elaboration, converting a subset of the Verilog Hardware Description Language (HDL) into a BLIF netlist.

See also

[JKGS10]

INSTALL

Prerequisites

  1. ctags
  2. bison
  3. flex
  4. gcc 5.x
  5. cmake 2.8.12 (minimum version)
  6. time
  7. cairo

Build

To build ODIN, run “make odin_II” from the vtr root directory.

Note

ODIN uses CMake as it’s build system. CMake provides a protable cross-platform build systems with many useful features. For unix-like systems we provide a wrapper Makefile which supports the traditional make and make clean commands, but calls CMake behind the scenes.

Warning

After you build Odin, please run the included verify_microbenchmarks.sh script. This will automatically compile, simulate, and verify all of the included microbenchmark circuits to ensure that Odin is working correctly on your system.

USAGE

./odin_II [args]

Required [args]

-c <XML Configuration File> fpga_architecture_file.xml format is specified from VPR
-V <Verilog HDL File> You may specify multiple verilog HDL files for synthesis
-b <BLIF File>  

Optional [args]

-o <output file> full output path and file name for the blif output file
-a <architecture file> an FPGA architecture file in VPR format to map to
-G   Output netlist graph in GraphViz viewable .dot format. (net.dot, opens with dotty)
-A   Output AST graph in in GraphViz viewable .dot format.
-W   Print all warnings. (Can be substantial.)
-h   Print help

Simulation

Note

Simulation always produces files:

  • input_vectors
  • output_vectors
  • test.do (ModelSim)

Activate Simulation with [args]

-g <Number of random test vectors> will simulate the generated netlist with the entered number of clock cycles using pseudo-random test vectors. These vectors and the resulting output vectors are written to “input_vectors” and “output_vectors” respectively. You can supply a predefined input vector using -t
-L <Comma-separated list> Comma-separated list of primary inputs to hold high at cycle 0, and low for all subsequent cycles.
-3   Generate three valued logic. (Default is binary.)
-t <input vector file> Supply a predefined input vector file
-U0   initial register value to 0
-U1   initial register value to 1
-UX   initial register value to X(unknown) (DEFAULT)

Simulation Optional [args]

-T <output vector file> The output vectors is verified against the supplied predefined output vector file
-E   Output after both edges of the clock. (Default is to output only after the falling edge.)
-R   Output after rising edge of the clock only. (Default is to output only after the falling edge.)
-p <Comma-separated list> Comma-separated list of additional pins/nodes to monitor during simulation. (view NOTES)

NOTES

Example for -p:

-p input~0,input~1 monitors pin 0 and 1 of input
-p input monitors all pins of input as a single port
-p input~ monitors all pins of input as separate ports. (split)

Note

Matching for -p is done via strstr so general strings will match all similar pins and nodes. (Eg: FF_NODE will create a single port with all flipflops)

Examples .xml configuration file for -c

<config>
        <verilog_files>
                <!-- Way of specifying multiple files in a project! -->
                <verilog_file>verilog_file.v</verilog_file>
        </verilog_files>
        <output>
                <!-- These are the output flags for the project -->
                <output_type>blif</output_type>
                <output_path_and_name>./output_file.blif</output_path_and_name>
                <target>
                        <!-- This is the target device the output is being built for -->
                        <arch_file>fpga_architecture_file.xml</arch_file>
                </target>
        </output>
        <optimizations>
                <!-- This is where the optimization flags go -->
        </optimizations>
        <debug_outputs>
                <!-- Various debug options -->
                <debug_output_path>.</debug_output_path>
                <output_ast_graphs>1</output_ast_graphs>
                <output_netlist_graphs>1</output_netlist_graphs>
        </debug_outputs>
</config>

Note

Hard blocks can be simulated; given a hardblock named block in the architecture file with an instance of it named instance in the verilog file, write a C method with signature defined in SRC/sim_block.h and compile it with an output filename of block+instance.so in the directory you plan to invoke Odin_II from.

When compiling the file, you’ll need to specify the following arguments to the compiler (assuming that you’re in the SANBOX directory):

cc -I../../libarchfpga_6/include/ -L../../libarchfpga_6 -lvpr_6 -lm --shared -o block+instance.so block.c.

If the netlist generated by Odin II contains the definition of a hardblock which doesn’t have a shared object file defined for it in the working directory, Odin II will not work if you specify it to use the simulator with the -g or -t options.

Warning

Use of static memory within the simulation code necessitates compiling a distinct shared object file for each instance of the block you wish to simulate. The method signature the simulator expects contains only int and int[] parameters, leaving the code provided to simulate the hard blokc agnostic of the internal Odin II data structures. However, a cycle parameter is included to provide researchers with the ability to delay results of operations performed by the simulation code.

Examples vector file for -t or -T

# Example vector file
intput_1 input_2 output_1 output_2 output_3
# Comment
0 0XA 1 0XD 1101

Note

Each line represents a vector. Each value must be specified in binary or hex. Comments may be included by placing an # at the start of the line. Blank lines are ignored. Values may be separated by non-newline whitespace. (tabs and spaces) Hex values must be prefixed with 0X.

Each line in the vector file represents one cycle, or one falling edge and one rising edge. Input vectors are read on a falling edge, while output vectors are written on a rising edge.

Verilog Synthesizable Keyword Support:

Supported Keyword NOT Sup. Keyword Supported Operators NOT Sup. Operators
@() automatic != -:
@* deassign !== +:
`define disable == >>>
always edge ===  
and endtask =>  
assign forever **  
case macromodule ^~  
defparam repeat <<<  
end signed >=  
endfunction specparam ||  
endmodule task ~&  
begin   &&  
default   <<  
else   <=  
endcase   >>  
endspecify   ~^  
for   ~|  
function      
if      
inout      
input      
integer      
localparam      
module      
nand      
negedge      
nor      
not      
or      
output      
parameter      
posedge      
reg      
specify      
while      
wire      
xnor      
xor      

Verilog NON-Synthesizable Keyword Support:

Supported Keyword NOT Sup. Keyword Supported Operators NOT Sup. Operators
initial casex   &&&
  casez    
  endprimitive    
  endtable    
  event    
  force    
  fork    
  join    
  primitive    
  release    
  table    
  time    
  wait    

Verilog Gate Level Modeling Support:

Supported Keyword NOT Sup. Keyword
  buf
  bufif0
  bufif1
  cmos
  highz0
  highz0
  highz1
  highz1
  large
  medium
  nmos
  notif0
  notif1
  pmos
  pull0
  pull1
  pulldown
  pullup
  rcmos
  rnmos
  rpmos
  rtran
  rtranif0
  rtranif1
  scalared
  small
  strong0
  strong0
  strong1
  strong1
  supply0
  supply1
  tran
  tranif0
  tranif1
  tri
  tri0
  tri1
  triand
  trior
  vectored
  wand
  weak0
  weak0
  weak1
  weak1
  wor

DOCUMENTING ODIN II

Any new command line options added to Odin II should be fully documented by the print_usage() function within odin_ii.c before checking in the changes.

TESTING ODIN II

The verify_microbenchmarks.sh and verify_regression_tests.sh scripts compile and simulate the microbenchmarks and a larger set of benchmark circuits. These scripts use simulation results which have been verified against ModelSim.

After you build Odin II, run verify_microbenchmarks.sh to ensure that everything is working correctly on your system. Unlike the verify_regression_tests.sh script, verify_microbenchmarks.sh also simulates the blif output, as well as simulating the verilog with and without the architecture file.

Before checking in any changes to Odin II, please run both of these scripts to ensure that both of these scripts execute correctly. If there is a failure, use ModelSim to verify that the failure is within Odin II and not a faulty regression test. The Odin II simulator will produce a test.do file containing clock and input vector information for ModelSim.

When additional circuits are found to agree with ModelSim, they should be added to these test sets. When new features are added to Odin II, new microbenchmarks should be developed which test those features for regression. Use existing circuits as a template for the addition of new circuits.

USING MODELSIM TO TEST ODIN II

ModelSim may be installed as part of the Quartus II Web Edition IDE. Load the Verilog circuit into a new project in ModelSim. Compile the circuit, and load the resulting library for simulation.

Simulate the circuit in Odin II using the -E option to ensure that Odin II outputs both edges of the clock. You may use random vectors via the -g option, or specify your own input vectors using the -t option. When simulation is complete, load the resulting test.do file into your ModelSim project and execute it. You may now directly compare the vectors in the output_vectors file with those produced by ModelSim.

To add the verified vectors and circuit to an existing test set, move the verilog file (eg: test_circuit.v) to the test set folder. Next, move the input_vectors file to the test set folder, and rename it test_circuit_input. Finally, move the output_vectors file to the test set folder and rename it test_circuit_output.

CONTACT

jamieson dot peter at gmail dot com ken at unb dot ca - We will service all requests as timely as possible, but please explain the problem with enough detail to help.