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/*
 *                              .--------------. .----------------. .------------.
 *                             | .------------. | .--------------. | .----------. |
 *                             | | ____  ____ | | | ____    ____ | | |   ______ | |
 *                             | ||_   ||   _|| | ||_   \  /   _|| | | .' ___  || |
 *       ___  _ __   ___ _ __  | |  | |__| |  | | |  |   \/   |  | | |/ .'   \_|| |
 *      / _ \| '_ \ / _ \ '_ \ | |  |  __  |  | | |  | |\  /| |  | | || |       | |
 *       (_) | |_) |  __/ | | || | _| |  | |_ | | | _| |_\/_| |_ | | |\ `.___.'\| |
 *      \___/| .__/ \___|_| |_|| ||____||____|| | ||_____||_____|| | | `._____.'| |
 *           | |               | |            | | |              | | |          | |
 *           |_|               | '------------' | '--------------' | '----------' |
 *                              '--------------' '----------------' '------------'
 *
 *  openHMC - An Open Source Hybrid Memory Cube Controller
 *  (C) Copyright 2014 Computer Architecture Group - University of Heidelberg
 *  www.ziti.uni-heidelberg.de
 *  B6, 26
 *  68159 Mannheim
 *  Germany
 *
 *  Contact: openhmc@ziti.uni-heidelberg.de
 *  http://ra.ziti.uni-heidelberg.de/openhmc
 *
 *   This source file is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This source file is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this source file.  If not, see <http://www.gnu.org/licenses/>.
 *
 *
 */

//
// hmc_packet
//

`ifndef HMC_PACKET_SV
`define HMC_PACKET_SV

`define HMC_TYPE_MASK 6'h38

class hmc_packet extends uvm_sequence_item;

        // request header fields
        rand bit [2:0]                  cube_ID;                                // CUB
        rand bit [33:0]         address;                                // ADRS
        rand bit [8:0]                  tag;                                    // TAG
        rand bit [3:0]                  packet_length;                  // LNG 128-bit (16-byte) flits
        rand bit [3:0]                  duplicate_length;               // DLN
        rand hmc_command_encoding       command;                        // CMD

        bit [127:0]                             payload[$];                             // 16-byte granularity

        // request tail fields
        rand bit [4:0]                  return_token_count;             // RTC
        rand bit [2:0]                  source_link_ID;                 // SLID
        rand bit [2:0]                  sequence_number;                // SEQ
        rand bit [7:0]                  forward_retry_pointer;  // FRP
        rand bit [7:0]                  return_retry_pointer;   // RRP
        rand bit [31:0]         packet_crc;                             // CRC

        // response header fields not used before
        rand bit [8:0]                  return_tag;                             // TGA (Optional)

        // response tail fields not used before
        rand bit [6:0]                  error_status;                   // ERRSTAT
        rand bit                                data_invalid;                   // DINV

        // special bits for IRTRY
        rand bit                                start_retry;
        rand bit                                clear_error_abort;

        // CRC status fields
        rand bit                                poisoned;                               // Inverted CRC
        rand bit                                crc_error;

        // helper fields
        rand int                                flit_delay;
        
        int                                             timestamp;

        `uvm_object_utils_begin(hmc_packet)
                `uvm_field_int(flit_delay, UVM_ALL_ON | UVM_NOPACK | UVM_DEC | UVM_NOCOMPARE | UVM_DEC)
                `uvm_field_int(cube_ID, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(address, UVM_ALL_ON | UVM_NOPACK | UVM_HEX)
                `uvm_field_int(tag, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(packet_length, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(duplicate_length, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_enum(hmc_command_encoding, command, UVM_ALL_ON | UVM_NOPACK )
                `uvm_field_queue_int(payload, UVM_ALL_ON | UVM_NOPACK)
                `uvm_field_int(return_token_count, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(source_link_ID, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(sequence_number, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(forward_retry_pointer, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(return_retry_pointer, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(packet_crc, UVM_ALL_ON | UVM_NOPACK | UVM_HEX)
                `uvm_field_int(return_tag, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(error_status, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(data_invalid, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(poisoned, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
                `uvm_field_int(crc_error, UVM_ALL_ON | UVM_NOPACK | UVM_DEC)
        `uvm_object_utils_end

        constraint c_poisoned { poisoned == 0; }
        constraint c_cube_id {cube_ID ==0;}
        constraint c_address {
                soft address < 80000000;
                ((command & `HMC_TYPE_MASK) == HMC_FLOW_TYPE) -> address == 0;  
                soft address[3:0]==4'h0;
        }
        constraint c_source_link_ID {source_link_ID ==0;}
        constraint c_crc_error { crc_error == 0; }
        constraint c_matching_length { packet_length == duplicate_length; }
        constraint c_return_tag { return_tag == 0; }
        constraint c_packet_length { (
                                                (packet_length == 2 && command == HMC_POSTED_WRITE_16) ||
                                                (packet_length == 3 && command == HMC_POSTED_WRITE_32) ||
                                                (packet_length == 4 && command == HMC_POSTED_WRITE_48) ||
                                                (packet_length == 5 && command == HMC_POSTED_WRITE_64) ||
                                                (packet_length == 6 && command == HMC_POSTED_WRITE_80) ||
                                                (packet_length == 7 && command == HMC_POSTED_WRITE_96) ||
                                                (packet_length == 8 && command == HMC_POSTED_WRITE_112) ||
                                                (packet_length == 9 && command == HMC_POSTED_WRITE_128) ||
                                                (packet_length == 2 && command == HMC_WRITE_16) ||
                                                (packet_length == 3 && command == HMC_WRITE_32) ||
                                                (packet_length == 4 && command == HMC_WRITE_48) ||
                                                (packet_length == 5 && command == HMC_WRITE_64) ||
                                                (packet_length == 6 && command == HMC_WRITE_80) ||
                                                (packet_length == 7 && command == HMC_WRITE_96) ||
                                                (packet_length == 8 && command == HMC_WRITE_112) ||
                                                (packet_length == 9 && command == HMC_WRITE_128) ||
                                                (packet_length > 1 && packet_length <= 9 && command == HMC_READ_RESPONSE) ||
                                                (packet_length == 1 && command == HMC_WRITE_RESPONSE) ||
                                                (packet_length == 1 && command == HMC_MODE_WRITE_RESPONSE) ||
                                                (packet_length == 1 && command == HMC_ERROR_RESPONSE) ||
                                                (packet_length == 2 && (command & `HMC_TYPE_MASK) == HMC_MISC_WRITE_TYPE) ||
                                                (packet_length == 2 && (command & `HMC_TYPE_MASK) == HMC_POSTED_MISC_WRITE_TYPE) ||
                                                (packet_length == 1 && (command & `HMC_TYPE_MASK) == HMC_MODE_READ_TYPE) ||
                                                (packet_length == 1 && (command & `HMC_TYPE_MASK) == HMC_READ_TYPE) ||
                                                (packet_length == 1 && (command & `HMC_TYPE_MASK) == HMC_FLOW_TYPE)
                ); }
        constraint c_flit_delay {
                soft flit_delay dist{0:/90, [1:8]:/8, [8:200]:/2  };
        }
        constraint c_error_status {
                soft error_status == 0;
        }
        
        constraint c_data_invalid {
                soft data_invalid == 0;
        }
        
        
        constraint c_pret {
                (command == HMC_PRET)-> forward_retry_pointer   ==0;
                (command == HMC_PRET)-> sequence_number                 ==0;
        }
        constraint c_irtry{
                (command == HMC_IRTRY)                                                  -> start_retry                  != clear_error_abort;
                ((command == HMC_IRTRY)&&(start_retry))                 ->forward_retry_pointer == 1;
                ((command == HMC_IRTRY)&&(clear_error_abort))   ->forward_retry_pointer == 2;
                (command == HMC_IRTRY)                                                  -> sequence_number              == 0;
        }
        
        constraint c_flow {
                ((command & `HMC_TYPE_MASK) == HMC_FLOW_TYPE) -> tag == 0;
                ((command & `HMC_TYPE_MASK) == HMC_FLOW_TYPE) -> cube_ID == 0;
        }
        
        function new (string name = "hmc_packet");
                super.new(name);
        endfunction : new

    function void post_randomize();
                bit [127:0] rand_flit;

        super.post_randomize();

                if (packet_length > 9)
                        `uvm_fatal(get_type_name(),$psprintf("post_randomize packet_length = %0d",packet_length))

                `uvm_info("AXI Packet queued",$psprintf("%0s packet_length = %0d",command.name(), packet_length), UVM_HIGH)
                
                if (packet_length < 2)
                        return;

                for (int i=0; i<packet_length-1; i++) begin
                        randomize_flit_successful : assert (std::randomize(rand_flit));
                        payload.push_back(rand_flit);
                end
                if ((command == HMC_POSTED_DUAL_8B_ADDI)||
                        (command == HMC_DUAL_8B_ADDI)) begin
                        payload[0] [63:32] = 32'b0;
                        payload[0][127:96] = 32'b0;
                end
                
                if ((command == HMC_MODE_WRITE)|| (command == HMC_MODE_READ)) begin
                        payload[0][127:32] = 96'b0;
                end
    endfunction

        function hmc_command_type get_command_type();

                case(command & `HMC_TYPE_MASK)
                        HMC_FLOW_TYPE:                          return HMC_FLOW_TYPE;
                        HMC_READ_TYPE:                          return HMC_READ_TYPE;
                        HMC_MODE_READ_TYPE:                     return HMC_MODE_READ_TYPE;
                        HMC_POSTED_WRITE_TYPE:          return HMC_POSTED_WRITE_TYPE;
                        HMC_POSTED_MISC_WRITE_TYPE:     return HMC_POSTED_MISC_WRITE_TYPE;
                        HMC_WRITE_TYPE:                         return HMC_WRITE_TYPE;
                        HMC_MISC_WRITE_TYPE:            return HMC_MISC_WRITE_TYPE;
                        HMC_RESPONSE_TYPE:                      return HMC_RESPONSE_TYPE;
                        default: uvm_report_fatal(get_type_name(), $psprintf("command with an illegal command type='h%0h!", command));
                endcase

        endfunction : get_command_type

/*
                The CRC algorithm used on the HMC is the Koopman CRC-32K. This algorithm was
                chosen for the HMC because of its balance of coverage and ease of implementation. The
                polynomial for this algorithm is:
                x32 + x30 + x29 + x28 + x26 + x20 + x19 + x17 + x16 + x15 + x11 + x10 + x7 + x6 + x4 + x2 + x + 1

                bit [31:0] polynomial = 33'b1_0111_0100_0001_1011_1000_1100_1101_0111;  // Normal

                The CRC calculation operates on the LSB of the packet first. The packet CRC calculation
                must insert 0s in place of the 32-bits representing the CRC field before generating or
                checking the CRC. For example, when generating CRC for a packet, bits [63: 32] of the
                Tail presented to the CRC generator should be all zeros. The output of the CRC generator
                will have a 32-bit CRC value that will then be inserted in bits [63:32] of the Tail before
                forwarding that FLIT of the packet. When checking CRC for a packet, the CRC field
                should be removed from bits [63:32] of the Tail and replaced with 32-bits of zeros, then
                presented to the CRC checker. The output of the CRC checker will have a 32-bit CRC
                value that can be compared with the CRC value that was removed from the tail. If the two
                compare, the CRC check indicates no bit failures within the packet.
*/

        function bit [31:0] calculate_crc();
                bit bitstream[];
                packer_succeeded : assert (pack(bitstream) > 0);
                return calc_crc(bitstream);
        endfunction : calculate_crc
        
        function bit [31:0] calc_crc(bit bitstream[]);
                bit [32:0] polynomial = 33'h1741B8CD7; // Normal
                
                bit [32:0] remainder = 33'h0;
                for( int i=0; i < bitstream.size()-32; i++ ) begin      // without the CRC
                        remainder = {remainder[31:0], bitstream[i]};
                        if( remainder[32] ) begin
                                remainder = remainder ^ polynomial;
                        end
                end

                for( int i=0; i < 64; i++ ) begin       // zeroes for CRC and remainder
                        remainder = {remainder[31:0], 1'b0};
                        if( remainder[32] ) begin
                                remainder = remainder ^ polynomial;
                        end
                end

                return remainder[31:0];
        endfunction : calc_crc

        virtual function void do_pack(uvm_packer packer);

                super.do_pack(packer);
                packer.big_endian = 0;

                // pack header half flit
                case(command & `HMC_TYPE_MASK)
                        HMC_FLOW_TYPE:
                                case (command)
                                        HMC_NULL:               packer.pack_field( {64'h0}, 64);
                                        HMC_PRET:               packer.pack_field ( {3'h0, 3'h0, 34'h0, 9'h0, duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                                        HMC_TRET:               packer.pack_field ( {3'h0, 3'h0, 34'h0, 9'h0, duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                                        HMC_IRTRY:              packer.pack_field ( {3'h0, 3'h0, 34'h0, 9'h0, duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                                        default: uvm_report_fatal(get_type_name(), $psprintf("pack function called for a hmc_packet with an illegal FLOW type='h%0h!", command));
                                endcase
                        HMC_READ_TYPE:                  packer.pack_field ( {cube_ID[2:0], 3'h0, address[33:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        HMC_MODE_READ_TYPE:             packer.pack_field ( {cube_ID[2:0], 3'h0, 34'h0, tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        HMC_POSTED_WRITE_TYPE:  packer.pack_field ( {cube_ID[2:0], 3'h0, address[33:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        HMC_WRITE_TYPE:                 packer.pack_field ( {cube_ID[2:0], 3'h0, address[33:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        HMC_POSTED_MISC_WRITE_TYPE:     packer.pack_field ( {cube_ID[2:0], 3'h0, address[33:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        HMC_MISC_WRITE_TYPE:    packer.pack_field ( {cube_ID[2:0], 3'h0, address[33:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        HMC_RESPONSE_TYPE:              packer.pack_field ( {22'h0, source_link_ID[2:0], 6'h0, return_tag[8:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], 1'b0, command[5:0]}, 64);
                        default: uvm_report_fatal(get_type_name(), $psprintf("pack function called for a hmc_packet with an illegal command type='h%0h!", command));
                endcase

                // Allow for errors when packet_length != duplicate_length
                if ((packet_length == duplicate_length) && payload.size() + 1 != packet_length && command != HMC_NULL)
                        uvm_report_fatal(get_type_name(), $psprintf("pack function size mismatch payload.size=%0d packet_length=%0d!", payload.size(), packet_length));

                // pack payload
                for( int i=0; i<payload.size(); i++ ) packer.pack_field ( payload[i], 128);

                // pack tail half flit
                case(command & `HMC_TYPE_MASK)
                        HMC_FLOW_TYPE:
                                case (command)
                                        HMC_NULL:               packer.pack_field( {64'h0}, 64);
                                        HMC_PRET:               packer.pack_field ( {packet_crc[31:0], 5'h0, 3'h0, 5'h0, 3'h0, 8'h0, return_retry_pointer[7:0]}, 64);
                                        HMC_TRET:               packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], 3'h0, 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                                        HMC_IRTRY:              packer.pack_field ( {packet_crc[31:0], 5'h0, 3'h0, 5'h0, 3'h0, 6'h0, clear_error_abort, start_retry, return_retry_pointer[7:0]}, 64);
                                        default: uvm_report_fatal(get_type_name(), $psprintf("pack function (tail) called for a hmc_packet with an illegal FLOW type='h%0h!", command));
                                endcase
                        HMC_READ_TYPE:                  packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        HMC_POSTED_WRITE_TYPE:  packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        HMC_WRITE_TYPE:                 packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        HMC_MODE_READ_TYPE:             packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        HMC_POSTED_MISC_WRITE_TYPE:     packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        HMC_MISC_WRITE_TYPE:    packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], 5'h0, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        HMC_RESPONSE_TYPE:              packer.pack_field ( {packet_crc[31:0], return_token_count[4:0], error_status[6:0], data_invalid, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}, 64);
                        default: uvm_report_fatal(get_type_name(), $psprintf("pack function (tail) called for a hmc_packet with an illegal command type='h%0h!", command));
                endcase
        endfunction : do_pack


        virtual function void do_unpack(uvm_packer packer);
                bit [63:0]      header;
                bit [63:0]      tail;
                bit [31:0]      calculated_crc;
                bit [21:0]      rsvd22;
                bit [5:0]       rsvd6;
                bit [4:0]       rsvd5;
                bit [2:0]       rsvd3;
                bit             rsvd1;

                bit bitstream[];

                super.do_unpack(packer);
                packer.big_endian = 0;

                packer.get_bits(bitstream);
                
                for (int i = 0; i <32; i++)begin
                        packet_crc[i] = bitstream[bitstream.size()-32 +i];
                end
                
                calculated_crc = calc_crc(bitstream);
                // header
                header = packer.unpack_field(64);
                command[5:0] = header[5:0];//-- doppelt?

                if (get_command_type != HMC_RESPONSE_TYPE)
                        {cube_ID[2:0], rsvd3, address[33:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], rsvd1, command[5:0]}  = header;
                else
                        {rsvd22[21:0], source_link_ID[2:0], rsvd6[5:0], return_tag[8:0], tag[8:0], duplicate_length[3:0], packet_length[3:0], rsvd1, command[5:0]}      = header;
                // Unpack should not be called with length errors
                if (duplicate_length != packet_length || packet_length == 0)
                        `uvm_fatal(get_type_name(), $psprintf("do_unpack: length mismatch dln=%0d len=%0d cmd=%0d!", duplicate_length, packet_length, command));

                // payload
                for (int i = 0; i < packet_length-1; i++)
                        payload.push_back(packer.unpack_field(128));

                // tail
                tail = packer.unpack_field(64);
                if (get_command_type != HMC_RESPONSE_TYPE) 
                        {packet_crc[31:0], return_token_count[4:0], source_link_ID[2:0], rsvd5, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}    = tail;
                else
                        {packet_crc[31:0], return_token_count[4:0], error_status[6:0], data_invalid, sequence_number[2:0], forward_retry_pointer[7:0], return_retry_pointer[7:0]}       = tail;

                start_retry                     = (command == HMC_IRTRY ? forward_retry_pointer[0] : 1'b0);
                clear_error_abort       = (command == HMC_IRTRY ? forward_retry_pointer[1] : 1'b0);

                crc_error = 0;

                poisoned = (packet_crc == ~calculated_crc) ? 1'b1 : 1'b0;
                if (packet_crc != calculated_crc &&  !poisoned )
                begin
                        crc_error = 1;
                end
        endfunction : do_unpack


        virtual function bit compare_adaptive_packet(hmc_packet rhs, uvm_comparer comparer);

                string name_string;

                compare_adaptive_packet &= comparer.compare_field("packet_length", packet_length, rhs.packet_length, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("payload.size()", payload.size(), rhs.payload.size(), 64, UVM_DEC);

                for (int i=0; i<packet_length; i++)
                begin
                        if (!compare_adaptive_packet)
                                return 0;
                        $sformat(name_string, "payload[%0d]", i);
                        compare_adaptive_packet &= comparer.compare_field(name_string, payload[i], rhs.payload[i], 128, UVM_HEX);
                end

                compare_adaptive_packet &= comparer.compare_field("cube_ID", cube_ID, rhs.cube_ID, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("address", address, rhs.address, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("tag", tag, rhs.tag, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("packet_length", packet_length, rhs.packet_length, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("duplicate_length", duplicate_length, rhs.duplicate_length, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("command", command, rhs.command, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("return_token_count", return_token_count, rhs.return_token_count, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("source_link_ID", source_link_ID, rhs.source_link_ID, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("sequence_number", sequence_number, rhs.sequence_number, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("forward_retry_pointer", forward_retry_pointer, rhs.forward_retry_pointer, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("return_tag", return_tag, rhs.return_tag, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("error_status", error_status, rhs.error_status, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("data_invalid", data_invalid, rhs.data_invalid, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("start_retry", start_retry, rhs.start_retry, 64, UVM_DEC);
                compare_adaptive_packet &= comparer.compare_field("clear_error_abort", clear_error_abort, rhs.clear_error_abort, 64, UVM_DEC);

        endfunction : compare_adaptive_packet

endclass : hmc_packet

`endif // HMC_PACKET_SV