fpga_lib/common.pkg at develop · miketsivinsky/fpga_lib · GitHub

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//******************************************************************************
//*
//*      Project:     Any
//*
//*      Description: Common code definitions file
//*
//*      Version 1.0
//*
//*      Copyright (c) 2008-2010, Harry E. Zhurov
//*
//*      $Revision: 37 $
//*      $Date:: 2010-07-28 20:56:24 #$
//*
//------------------------------------------------------------------------------

`ifndef COMMON_H
`define COMMON_H

package common;

//------------------------------------------------------------------------------
function integer clog2 (input integer num); // this function calculates ceil(log2(num))
begin
    num = num - 1;                          // without this statement clog2(32) will be 6 but must be 5
    for (clog2 = 0; num > 0; clog2 = clog2 + 1)
        num = num >> 1;
end
endfunction
//------------------------------------------------------------------------------
function int max(input int x, input int y);
    return x > y ? x : y;
endfunction
//------------------------------------------------------------------------------
function int bits(input int x);
    return  ( x == (1 << clog2(x)) ) ? clog2(x)+1 : clog2(x);
endfunction
//------------------------------------------------------------------------------


endpackage
import common::*;

`endif // COMMON_H