// ---------------------------------------------------------------------- // Copyright (c) 2016, The Regents of the University of California All // rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following // disclaimer in the documentation and/or other materials provided // with the distribution. // // * Neither the name of The Regents of the University of California // nor the names of its contributors may be used to endorse or // promote products derived from this software without specific // prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL REGENTS OF THE // UNIVERSITY OF CALIFORNIA BE LIABLE FOR ANY DIRECT, INDIRECT, // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, // BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS // OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND // ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR // TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE // USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH // DAMAGE. // ---------------------------------------------------------------------- //---------------------------------------------------------------------------- // Filename: functions.vh // Version: 1.00 // Verilog Standard: Verilog-2005 // Description: A simple file containing clog2 function declarations // Author: Dustin Richmond (@darichmond) //----------------------------------------------------------------------------- `ifndef __FUNCTIONS_VH `define __FUNCTIONS_VH 1 function integer clog2; input [31:0] v; reg [31:0] value; begin value = v; if (value == 1) begin clog2 = 0; end else begin value = value-1; for (clog2=0; value>0; clog2=clog2+1) value = value>>1; end end endfunction // clog2s -- calculate the ceiling log2 value, min return is 1 (safe). function integer clog2s; input [31:0] v; reg [31:0] value; begin value = v; if (value == 1) begin clog2s = 1; end else begin value = value-1; for (clog2s=0; value>0; clog2s=clog2s+1) value = value>>1; end end endfunction `endif