verif/model/pcie/dll/calculate_lcrc.cpp

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//
// OpenSPARC T2 Processor File: calculate_lcrc.cpp
// Copyright (C) 1995-2007 Sun Microsystems, Inc. All Rights Reserved
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#include "dll_top.hpp"

namespace pcie {

    /**
       This function calculates the LCRC value
    **/
    sc_uint<32> dll_top::calculate_lcrc(RefPciePacket received_packet,int pkt_begin,int pkt_end)
    {
        int index,byte_index;;
        sc_uint<32> tmp_lcrc;
        sc_uint<8> byte;
        sc_uint<32> lcrc_mapped;

        /// Resetting the initial lcrc value
        lcrc = 0xffffffff;

        for(byte_index=pkt_begin; byte_index < pkt_end; byte_index++)
        {
            byte = received_packet->get_byte(byte_index);
            for (index=0; index < 8; index++)
            {
                tmp_lcrc = lcrc;
                lcrc[0]  = byte[index] ^ tmp_lcrc[31];
                lcrc[1]  = byte[index] ^ tmp_lcrc[0] ^ tmp_lcrc[31];
                lcrc[2]  = byte[index] ^ tmp_lcrc[1] ^ tmp_lcrc[31];
                lcrc[3]  = tmp_lcrc[2];
                lcrc[4]  = byte[index] ^ tmp_lcrc[3] ^ tmp_lcrc[31];
                lcrc[5]  = byte[index] ^ tmp_lcrc[4] ^ tmp_lcrc[31];
                lcrc[6]  = tmp_lcrc[5];
                lcrc[7]  = byte[index] ^ tmp_lcrc[6] ^ tmp_lcrc[31];
                lcrc[8]  = byte[index] ^ tmp_lcrc[7] ^ tmp_lcrc[31];
                lcrc[9]  = tmp_lcrc[8];
                lcrc[10] = byte[index] ^ tmp_lcrc[9] ^ tmp_lcrc[31];
                lcrc[11] = byte[index] ^ tmp_lcrc[10] ^ tmp_lcrc[31];
                lcrc[12] = byte[index] ^ tmp_lcrc[11] ^ tmp_lcrc[31];
                lcrc[13] = tmp_lcrc[12];
                lcrc[14] = tmp_lcrc[13];
                lcrc[15] = tmp_lcrc[14];
                lcrc[16] = byte[index] ^ tmp_lcrc[15] ^ tmp_lcrc[31];
                lcrc[17] = tmp_lcrc[16];
                lcrc[18] = tmp_lcrc[17];
                lcrc[19] = tmp_lcrc[18];
                lcrc[20] = tmp_lcrc[19];
                lcrc[21] = tmp_lcrc[20];
                lcrc[22] = byte[index] ^ tmp_lcrc[21] ^ tmp_lcrc[31];
                lcrc[23] = byte[index] ^ tmp_lcrc[22] ^ tmp_lcrc[31];
                lcrc[24] = tmp_lcrc[23];
                lcrc[25] = tmp_lcrc[24];
                lcrc[26] = byte[index] ^ tmp_lcrc[25] ^ tmp_lcrc[31];
                lcrc[27] = tmp_lcrc[26];
                lcrc[28] = tmp_lcrc[27];
                lcrc[29] = tmp_lcrc[28];
                lcrc[30] = tmp_lcrc[29];
                lcrc[31] = tmp_lcrc[30];

                lcrc_mapped[0] = ~lcrc[7];
                lcrc_mapped[1] = ~lcrc[6];
                lcrc_mapped[2] = ~lcrc[5];
                lcrc_mapped[3] = ~lcrc[4];
                lcrc_mapped[4] = ~lcrc[3];
                lcrc_mapped[5] = ~lcrc[2];
                lcrc_mapped[6] = ~lcrc[1];
                lcrc_mapped[7] = ~lcrc[0];

                lcrc_mapped[8]  = ~lcrc[15];
                lcrc_mapped[9]  = ~lcrc[14];
                lcrc_mapped[10] = ~lcrc[13];
                lcrc_mapped[11] = ~lcrc[12];
                lcrc_mapped[12] = ~lcrc[11];
                lcrc_mapped[13] = ~lcrc[10];
                lcrc_mapped[14] = ~lcrc[9];
                lcrc_mapped[15] = ~lcrc[8];

                lcrc_mapped[16] = ~lcrc[23];
                lcrc_mapped[17] = ~lcrc[22];
                lcrc_mapped[18] = ~lcrc[21];
                lcrc_mapped[19] = ~lcrc[20];
                lcrc_mapped[20] = ~lcrc[19];
                lcrc_mapped[21] = ~lcrc[18];
                lcrc_mapped[22] = ~lcrc[17];
                lcrc_mapped[23] = ~lcrc[16];

                lcrc_mapped[24] = ~lcrc[31];
                lcrc_mapped[25] = ~lcrc[30];
                lcrc_mapped[26] = ~lcrc[29];
                lcrc_mapped[27] = ~lcrc[28];
                lcrc_mapped[28] = ~lcrc[27];
                lcrc_mapped[29] = ~lcrc[26];
                lcrc_mapped[30] = ~lcrc[25];
                lcrc_mapped[31] = ~lcrc[24];
            }// for
        } // for
        return lcrc_mapped;
    }// void calculate_lcrc
}