how to pass 64 bit variables and more to PLI C model in verilog

[tariq786]

I have a C model of 128 bit AES (advanced encryption standard)

I want to make this C model as a reference model that is i want to pass input to this C model and the verilog model and compare the output of the two models to see if they have the same value or not.

The problem is that i dont know how to pass 128 bit values from verilog to C model.

Has anyone done some thing similar?

Please educate me and others

Thanks

 

[dave_59]

The easiest thing is to use the SystemVerilog DPI and import your C model.

SV code

module top;
   typedef byte a128_t[16];
   import "DPI-C" function void my_c_function (input a128_t f1,
					       output a128_t f2);
   a128_t a1,a2;
   initial begin
      void'(std::randomize(a1));
      $display("%p",a1);
      my_c_function(a1,a2);
      $display("%p",a2);
   end
endmodule

C code

#include "dpi.h"
void my_c_function (
		    const char* f1,
		    char* f2) {
  int i;
  //your algorithm goes here
  for(i=0;i<16;i++) *f2++ = (*f1++)+1;
}

Command line

 qverilog  DPI.sv -dpiheader dpi.h dpi.c