// // Copyright 2020 Ettus Research, A National Instruments Company // // SPDX-License-Identifier: LGPL-3.0-or-later // // Module: PkgChdrIfaceBfm // // Description: This package includes a high-level bus functional model (BFM) // for the AXIS-CHDR interface of a Transport Adapter or Stream Endpoint. // package PkgChdrIfaceBfm; import PkgChdrUtils::*; import PkgChdrBfm::*; typedef struct packed { chdr_vc_t vc; logic eob; logic eov; logic has_time; chdr_word_t timestamp; } packet_info_t; class ChdrIfaceBfm #(CHDR_W = 64) extends ChdrBfm #(CHDR_W); chdr_seq_num_t seq_num; // Sequence number protected int max_payload_length; // Maximum number of payload bytes per packet protected int ticks_per_word; // Timestamp increment per CHDR_W sized word // Class constructor to create a new BFM instance. // // m_chdr: Interface for the master connection (BFM's CHDR output) // s_chdr: Interface for the slave connection (BFM's CHDR input) // function new( virtual AxiStreamIf #(CHDR_W).master m_chdr, virtual AxiStreamIf #(CHDR_W).slave s_chdr, input int max_payload_length = 2**$bits(chdr_length_t), input int ticks_per_word = CHDR_W/32 ); super.new(m_chdr, s_chdr); this.seq_num = 0; set_max_payload_length(max_payload_length); set_ticks_per_word(ticks_per_word); endfunction : new // Set the maximum payload size for packets. This value is used to split // large send requests across multiple packets. // // max_length: Maximum payload length in bytes for each packet // function void set_max_payload_length(int max_payload_length); assert (max_payload_length % (CHDR_W/8) == 0) else begin $fatal(1, "ChdrIfaceBfm::set_max_payload_length: max_payload_length must be a multiple of CHDR_W in bytes"); end this.max_payload_length = max_payload_length; endfunction // Return the maximum payload size for packets. This value is used to split // large send requests across multiple packets. function int get_max_payload_length(); return max_payload_length; endfunction // Set the timestamp ticks per CHDR_W sized word. // // ticks_per_word: Amount to increment the timestamp per CHDR_W sized word // function void set_ticks_per_word(int ticks_per_word); this.ticks_per_word = ticks_per_word; endfunction // Return the timestamp ticks per CHDR_W sized word. function int get_ticks_per_word(); return ticks_per_word; endfunction // Send a CHDR data packet. // // data: Data words to insert into the CHDR packet. // data_bytes: The number of data bytes in the CHDR packet. This // is useful if the data is not a multiple of the // chdr_word_t size. // metadata: Metadata words to insert into the CHDR packet. Omit this // argument (or set to an empty array) to not include // metadata. // pkt_info: Data structure containing packet header information. // task send ( input chdr_word_t data[$], input int data_bytes = -1, input chdr_word_t metadata[$] = {}, input packet_info_t pkt_info = 0 ); ChdrPacket chdr_packet; chdr_header_t chdr_header; // Build packet chdr_packet = new(); chdr_header = '{ vc : pkt_info.vc, eob : pkt_info.eob, eov : pkt_info.eov, seq_num : seq_num++, pkt_type : pkt_info.has_time ? CHDR_DATA_WITH_TS : CHDR_DATA_NO_TS, dst_epid : dst_epid, default : 0 }; chdr_packet.write_raw(chdr_header, data, metadata, pkt_info.timestamp, data_bytes); // Send the packet put_chdr(chdr_packet); endtask : send // Send data as one or more CHDR data packets. The input data and metadata // is automatically broken into max_payload_length'd packets. If multiple // packets are needed, EOB and EOV are only applied to the last packet. // // data: Data words to insert into the CHDR packet. // data_bytes: The number of data bytes in the CHDR packet. This // is useful if the data is not a multiple of the // chdr_word_t size. // metadata: Metadata words to insert into the CHDR packet. Omit this // argument (or set to an empty array) to not include // metadata. // pkt_info: Data structure containing packet header information. // task send_packets ( input chdr_word_t data[$], input int data_bytes = -1, input chdr_word_t metadata[$] = {}, input packet_info_t pkt_info = 0 ); ChdrPacket chdr_packet; chdr_header_t chdr_header; chdr_pkt_type_t pkt_type; chdr_word_t timestamp; int num_pkts; int payload_length; int first_dword, last_dword; int first_mword, last_mword; bit eob, eov; chdr_word_t temp_data[$]; chdr_word_t temp_mdata[$]; num_pkts = $ceil(real'(data.size()*($bits(chdr_word_t)/8)) / max_payload_length); pkt_type = pkt_info.has_time ? CHDR_DATA_WITH_TS : CHDR_DATA_NO_TS; timestamp = pkt_info.timestamp; // Make sure there's not too much metadata for this number of packets assert(metadata.size()*$bits(chdr_word_t) < num_pkts * 2**$bits(chdr_num_mdata_t) * CHDR_W) else $fatal(1, "ChdrIfaceBfm::send: Too much metadata for this send request"); // Send the data, one packet at a time. for (int i = 0; i < num_pkts; i++) begin chdr_packet = new(); // Figure out which data chunk to send next if (i == num_pkts-1) begin // The last packet, which may or may not be full-sized eob = pkt_info.eob; eov = pkt_info.eov; payload_length = (data_bytes < 0) ? data_bytes : data_bytes % max_payload_length; first_dword = i*max_payload_length/($bits(chdr_word_t)/8); last_dword = data.size()-1; first_mword = i*(2**$bits(chdr_num_mdata_t) * CHDR_W / $bits(chdr_word_t)); last_mword = metadata.size()-1; end else begin // A full-sized packet, not the last eob = 1'b0; eov = 1'b0; payload_length = max_payload_length; first_dword = (i+0)*max_payload_length / ($bits(chdr_word_t)/8); last_dword = (i+1)*max_payload_length / ($bits(chdr_word_t)/8) - 1; first_mword = (i+0)*(2**$bits(chdr_num_mdata_t) * CHDR_W / $bits(chdr_word_t)); last_mword = (i+1)*(2**$bits(chdr_num_mdata_t) * CHDR_W / $bits(chdr_word_t)) - 1; last_mword = last_mword > metadata.size() ? metadata.size() : last_mword; end // Build the packet chdr_header = '{ vc : pkt_info.vc, eob : eob, eov : eov, seq_num : seq_num++, pkt_type : pkt_type, dst_epid : dst_epid, default : 0 }; // Copy region of data and metadata to be sent in next packet temp_data = data[first_dword : last_dword]; if (first_mword < metadata.size()) temp_mdata = metadata[first_mword : last_mword]; else temp_mdata = {}; // Build the packet chdr_packet.write_raw( chdr_header, temp_data, temp_mdata, timestamp, payload_length ); // Send the packet put_chdr(chdr_packet); // Update timestamp for next packet (in case this is not the last) timestamp += max_payload_length/(CHDR_W/8) * ticks_per_word; end endtask : send_packets // Receive a CHDR data packet and extract its contents. // // data: Data words from the received CHDR packet. // data_bytes: The number of data bytes in the CHDR packet. This // is useful if the data is not a multiple of the // chdr_word_t size. // metadata: Metadata words from the received CHDR packet. This // will be an empty array if there was no metadata. // pkt_info: Data structure to receive packet header information. // task recv_adv ( output chdr_word_t data[$], output int data_bytes, output chdr_word_t metadata[$], output packet_info_t pkt_info ); ChdrPacket chdr_packet; get_chdr(chdr_packet); data = chdr_packet.data; data_bytes = chdr_packet.data_bytes(); metadata = chdr_packet.metadata; pkt_info.timestamp = chdr_packet.timestamp; pkt_info.vc = chdr_packet.header.vc; pkt_info.eob = chdr_packet.header.eob; pkt_info.eov = chdr_packet.header.eov; pkt_info.has_time = chdr_packet.header.pkt_type == CHDR_DATA_WITH_TS ? 1 : 0; endtask : recv_adv // Receive a CHDR data packet and extract the data. Any metadata or // timestamp, if present, are discarded. // // data: Data words from the received CHDR packet. // data_bytes: The number of data bytes in the CHDR packet. This // is useful if the data is not a multiple of the // chdr_word_t size. // task recv(output chdr_word_t data[$], output int data_bytes); ChdrPacket chdr_packet; get_chdr(chdr_packet); data = chdr_packet.data; data_bytes = chdr_packet.data_bytes(); endtask : recv endclass : ChdrIfaceBfm endpackage : PkgChdrIfaceBfm