SystemVerilog DPI in NCSim?

Here’s the basics of creating a simple dpi file and using it from Ncsim.  In this example the simulator gets a real value from dpi and then passes it back to the dpi code.  I have numerous other examples using strings, integers...etc (tmackett@cadence.com)

Here’s the Verilog file (real_test.sv) :

module real_test ();

// map the C function name to the Verilog function name

import "DPI-C" context get_real_c = function real get_real_v ();

import "DPI-C" context put_real_c = function void put_real_v (real x);     

real pi;

initial

begin

$display("real_test");

pi = get_real_v();        // get a real number from the C code

$display("pi = %f", pi);  // display it

put_real_v(pi);           // send the real number back to C code  

end

endmodule

Here’s the dpi code (real_dpi.c).  Notice there is NO c main:

#include "svdpi.h"

// since we are using math functions, include the math library

#include         

// can use io_printf() instead of printf() to put into ncsim.log file

double get_real_c() {  // imported SV function

  // exercise DPI function - get calling scope

  printf("Function Calling HDL scope is %s \n", svGetNameFromScope(svGetScope() ) );

  return 3.14159;

}

void put_real_c(double n) {  // imported SV function

  // exercise DPI function - get calling scope

  printf("Function Calling HDL scope is %s \n", svGetNameFromScope(svGetScope() ) );

  printf("pi + 5.0 = %f\n", n+5.0);      

}

Here’s the script to compile everything:

rm -r INCA_libs

rm -r waves.shm

rm *.so

# make sure LD_LIBRARY_PATH includes . (or where the real_dpi.so lives)

# make sure using useful gcc version like 3.2.2, 3.3.3 etc

#create single header file for multiple dpi.c sources

ncvlog real_test.v -sv

# -dpiheader produces nothing for imported functions

ncelab -dpiheader dpi.h worklib.real_test:module

gcc -m32 -fPIC -g -shared -o real_dpi.so  real_dpi.c  -I/`ncroot`/tools/include

# use the Incisive supplied gdb

#xterm -e `ncroot`/tools/systemc/bin/gdb `ncroot`/tools/bin/ncsim &

Here’s the resulting log file:

ncsim> run

real_test

Function Calling HDL scope is real_test

pi = 3.141590

Function Calling HDL scope is real_test

pi + 5.0 = 8.141590

ncsim: *W,RNQUIE: Simulation is complete.

ncsim> exit

Here’s the basics of creating a simple dpi file and using it from Ncsim.  In this example the simulator gets a real value from dpi and then passes it back to the dpi code.  I have numerous other examples using strings, integers...etc (tmackett@cadence.com)

Here’s the Verilog file (real_test.sv) :

module real_test ();

// map the C function name to the Verilog function name

import "DPI-C" context get_real_c = function real get_real_v ();

import "DPI-C" context put_real_c = function void put_real_v (real x);     

real pi;

initial

begin

$display("real_test");

pi = get_real_v();        // get a real number from the C code

$display("pi = %f", pi);  // display it

put_real_v(pi);           // send the real number back to C code  

end

endmodule

Here’s the dpi code (real_dpi.c).  Notice there is NO c main:

#include "svdpi.h"

// since we are using math functions, include the math library

#include         

// can use io_printf() instead of printf() to put into ncsim.log file

double get_real_c() {  // imported SV function

  // exercise DPI function - get calling scope

  printf("Function Calling HDL scope is %s \n", svGetNameFromScope(svGetScope() ) );

  return 3.14159;

}

void put_real_c(double n) {  // imported SV function

  // exercise DPI function - get calling scope

  printf("Function Calling HDL scope is %s \n", svGetNameFromScope(svGetScope() ) );

  printf("pi + 5.0 = %f\n", n+5.0);      

}

Here’s the script to compile everything:

rm -r INCA_libs

rm -r waves.shm

rm *.so

# make sure LD_LIBRARY_PATH includes . (or where the real_dpi.so lives)

# make sure using useful gcc version like 3.2.2, 3.3.3 etc

#create single header file for multiple dpi.c sources

ncvlog real_test.v -sv

# -dpiheader produces nothing for imported functions

ncelab -dpiheader dpi.h worklib.real_test:module

gcc -m32 -fPIC -g -shared -o real_dpi.so  real_dpi.c  -I/`ncroot`/tools/include

# use the Incisive supplied gdb

#xterm -e `ncroot`/tools/systemc/bin/gdb `ncroot`/tools/bin/ncsim &

Here’s the resulting log file:

ncsim> run

real_test

Function Calling HDL scope is real_test

pi = 3.141590

Function Calling HDL scope is real_test

pi + 5.0 = 8.141590

ncsim: *W,RNQUIE: Simulation is complete.

ncsim> exit