/* Copyright (c) 2014-2017 Alex Forencich Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ // Language: Verilog 2001 `timescale 1ns / 1ps /* * UDP ethernet frame receiver (IP frame in, UDP frame out, 64 bit datapath) */ module udp_ip_rx_64 ( input wire clk, input wire rst, /* * IP frame input */ input wire input_ip_hdr_valid, output wire input_ip_hdr_ready, input wire [47:0] input_eth_dest_mac, input wire [47:0] input_eth_src_mac, input wire [15:0] input_eth_type, input wire [3:0] input_ip_version, input wire [3:0] input_ip_ihl, input wire [5:0] input_ip_dscp, input wire [1:0] input_ip_ecn, input wire [15:0] input_ip_length, input wire [15:0] input_ip_identification, input wire [2:0] input_ip_flags, input wire [12:0] input_ip_fragment_offset, input wire [7:0] input_ip_ttl, input wire [7:0] input_ip_protocol, input wire [15:0] input_ip_header_checksum, input wire [31:0] input_ip_source_ip, input wire [31:0] input_ip_dest_ip, input wire [63:0] input_ip_payload_tdata, input wire [7:0] input_ip_payload_tkeep, input wire input_ip_payload_tvalid, output wire input_ip_payload_tready, input wire input_ip_payload_tlast, input wire input_ip_payload_tuser, /* * UDP frame output */ output wire output_udp_hdr_valid, input wire output_udp_hdr_ready, output wire [47:0] output_eth_dest_mac, output wire [47:0] output_eth_src_mac, output wire [15:0] output_eth_type, output wire [3:0] output_ip_version, output wire [3:0] output_ip_ihl, output wire [5:0] output_ip_dscp, output wire [1:0] output_ip_ecn, output wire [15:0] output_ip_length, output wire [15:0] output_ip_identification, output wire [2:0] output_ip_flags, output wire [12:0] output_ip_fragment_offset, output wire [7:0] output_ip_ttl, output wire [7:0] output_ip_protocol, output wire [15:0] output_ip_header_checksum, output wire [31:0] output_ip_source_ip, output wire [31:0] output_ip_dest_ip, output wire [15:0] output_udp_source_port, output wire [15:0] output_udp_dest_port, output wire [15:0] output_udp_length, output wire [15:0] output_udp_checksum, output wire [63:0] output_udp_payload_tdata, output wire [7:0] output_udp_payload_tkeep, output wire output_udp_payload_tvalid, input wire output_udp_payload_tready, output wire output_udp_payload_tlast, output wire output_udp_payload_tuser, /* * Status signals */ output wire busy, output wire error_header_early_termination, output wire error_payload_early_termination ); /* UDP Frame Field Length Destination MAC address 6 octets Source MAC address 6 octets Ethertype (0x0800) 2 octets Version (4) 4 bits IHL (5-15) 4 bits DSCP (0) 6 bits ECN (0) 2 bits length 2 octets identification (0?) 2 octets flags (010) 3 bits fragment offset (0) 13 bits time to live (64?) 1 octet protocol 1 octet header checksum 2 octets source IP 4 octets destination IP 4 octets options (IHL-5)*4 octets source port 2 octets desination port 2 octets length 2 octets checksum 2 octets payload length octets This module receives an IP frame with header fields in parallel and payload on an AXI stream interface, decodes and strips the UDP header fields, then produces the header fields in parallel along with the UDP payload in a separate AXI stream. */ localparam [2:0] STATE_IDLE = 3'd0, STATE_READ_HEADER = 3'd1, STATE_READ_PAYLOAD = 3'd2, STATE_READ_PAYLOAD_LAST = 3'd3, STATE_WAIT_LAST = 3'd4; reg [2:0] state_reg = STATE_IDLE, state_next; // datapath control signals reg store_ip_hdr; reg store_hdr_word_0; reg store_last_word; reg [15:0] frame_ptr_reg = 16'd0, frame_ptr_next; reg [63:0] last_word_data_reg = 64'd0; reg [7:0] last_word_keep_reg = 8'd0; reg output_udp_hdr_valid_reg = 1'b0, output_udp_hdr_valid_next; reg [47:0] output_eth_dest_mac_reg = 48'd0; reg [47:0] output_eth_src_mac_reg = 48'd0; reg [15:0] output_eth_type_reg = 16'd0; reg [3:0] output_ip_version_reg = 4'd0; reg [3:0] output_ip_ihl_reg = 4'd0; reg [5:0] output_ip_dscp_reg = 6'd0; reg [1:0] output_ip_ecn_reg = 2'd0; reg [15:0] output_ip_length_reg = 16'd0; reg [15:0] output_ip_identification_reg = 16'd0; reg [2:0] output_ip_flags_reg = 3'd0; reg [12:0] output_ip_fragment_offset_reg = 13'd0; reg [7:0] output_ip_ttl_reg = 8'd0; reg [7:0] output_ip_protocol_reg = 8'd0; reg [15:0] output_ip_header_checksum_reg = 16'd0; reg [31:0] output_ip_source_ip_reg = 32'd0; reg [31:0] output_ip_dest_ip_reg = 32'd0; reg [15:0] output_udp_source_port_reg = 16'd0; reg [15:0] output_udp_dest_port_reg = 16'd0; reg [15:0] output_udp_length_reg = 16'd0; reg [15:0] output_udp_checksum_reg = 16'd0; reg input_ip_hdr_ready_reg = 1'b0, input_ip_hdr_ready_next; reg input_ip_payload_tready_reg = 1'b0, input_ip_payload_tready_next; reg busy_reg = 1'b0; reg error_header_early_termination_reg = 1'b0, error_header_early_termination_next; reg error_payload_early_termination_reg = 1'b0, error_payload_early_termination_next; // internal datapath reg [63:0] output_udp_payload_tdata_int; reg [7:0] output_udp_payload_tkeep_int; reg output_udp_payload_tvalid_int; reg output_udp_payload_tready_int_reg = 1'b0; reg output_udp_payload_tlast_int; reg output_udp_payload_tuser_int; wire output_udp_payload_tready_int_early; assign input_ip_hdr_ready = input_ip_hdr_ready_reg; assign input_ip_payload_tready = input_ip_payload_tready_reg; assign output_udp_hdr_valid = output_udp_hdr_valid_reg; assign output_eth_dest_mac = output_eth_dest_mac_reg; assign output_eth_src_mac = output_eth_src_mac_reg; assign output_eth_type = output_eth_type_reg; assign output_ip_version = output_ip_version_reg; assign output_ip_ihl = output_ip_ihl_reg; assign output_ip_dscp = output_ip_dscp_reg; assign output_ip_ecn = output_ip_ecn_reg; assign output_ip_length = output_ip_length_reg; assign output_ip_identification = output_ip_identification_reg; assign output_ip_flags = output_ip_flags_reg; assign output_ip_fragment_offset = output_ip_fragment_offset_reg; assign output_ip_ttl = output_ip_ttl_reg; assign output_ip_protocol = output_ip_protocol_reg; assign output_ip_header_checksum = output_ip_header_checksum_reg; assign output_ip_source_ip = output_ip_source_ip_reg; assign output_ip_dest_ip = output_ip_dest_ip_reg; assign output_udp_source_port = output_udp_source_port_reg; assign output_udp_dest_port = output_udp_dest_port_reg; assign output_udp_length = output_udp_length_reg; assign output_udp_checksum = output_udp_checksum_reg; assign busy = busy_reg; assign error_header_early_termination = error_header_early_termination_reg; assign error_payload_early_termination = error_payload_early_termination_reg; function [3:0] keep2count; input [7:0] k; case (k) 8'b00000000: keep2count = 4'd0; 8'b00000001: keep2count = 4'd1; 8'b00000011: keep2count = 4'd2; 8'b00000111: keep2count = 4'd3; 8'b00001111: keep2count = 4'd4; 8'b00011111: keep2count = 4'd5; 8'b00111111: keep2count = 4'd6; 8'b01111111: keep2count = 4'd7; 8'b11111111: keep2count = 4'd8; endcase endfunction function [7:0] count2keep; input [3:0] k; case (k) 4'd0: count2keep = 8'b00000000; 4'd1: count2keep = 8'b00000001; 4'd2: count2keep = 8'b00000011; 4'd3: count2keep = 8'b00000111; 4'd4: count2keep = 8'b00001111; 4'd5: count2keep = 8'b00011111; 4'd6: count2keep = 8'b00111111; 4'd7: count2keep = 8'b01111111; 4'd8: count2keep = 8'b11111111; endcase endfunction always @* begin state_next = STATE_IDLE; input_ip_hdr_ready_next = 1'b0; input_ip_payload_tready_next = 1'b0; store_ip_hdr = 1'b0; store_hdr_word_0 = 1'b0; store_last_word = 1'b0; frame_ptr_next = frame_ptr_reg; output_udp_hdr_valid_next = output_udp_hdr_valid_reg & ~output_udp_hdr_ready; error_header_early_termination_next = 1'b0; error_payload_early_termination_next = 1'b0; output_udp_payload_tdata_int = 64'd0; output_udp_payload_tkeep_int = 8'd0; output_udp_payload_tvalid_int = 1'b0; output_udp_payload_tlast_int = 1'b0; output_udp_payload_tuser_int = 1'b0; case (state_reg) STATE_IDLE: begin // idle state - wait for header frame_ptr_next = 16'd0; input_ip_hdr_ready_next = ~output_udp_hdr_valid_reg; if (input_ip_hdr_ready & input_ip_hdr_valid) begin input_ip_hdr_ready_next = 1'b0; input_ip_payload_tready_next = 1'b1; store_ip_hdr = 1'b1; state_next = STATE_READ_HEADER; end else begin state_next = STATE_IDLE; end end STATE_READ_HEADER: begin // read header state input_ip_payload_tready_next = 1'b1; if (input_ip_payload_tready & input_ip_payload_tvalid) begin // word transfer in - store it frame_ptr_next = frame_ptr_reg + 16'd8; state_next = STATE_READ_HEADER; case (frame_ptr_reg) 8'h00: begin store_hdr_word_0 = 1'b1; output_udp_hdr_valid_next = 1'b1; input_ip_payload_tready_next = output_udp_payload_tready_int_early; state_next = STATE_READ_PAYLOAD; end endcase if (input_ip_payload_tlast) begin error_header_early_termination_next = 1'b1; output_udp_hdr_valid_next = 1'b0; input_ip_hdr_ready_next = ~output_udp_hdr_valid_reg; input_ip_payload_tready_next = 1'b0; state_next = STATE_IDLE; end end else begin state_next = STATE_READ_HEADER; end end STATE_READ_PAYLOAD: begin // read payload input_ip_payload_tready_next = output_udp_payload_tready_int_early; output_udp_payload_tdata_int = input_ip_payload_tdata; output_udp_payload_tkeep_int = input_ip_payload_tkeep; output_udp_payload_tvalid_int = input_ip_payload_tvalid; output_udp_payload_tlast_int = input_ip_payload_tlast; output_udp_payload_tuser_int = input_ip_payload_tuser; if (input_ip_payload_tready & input_ip_payload_tvalid) begin // word transfer through frame_ptr_next = frame_ptr_reg+keep2count(input_ip_payload_tkeep); if (frame_ptr_next >= output_udp_length_reg) begin // have entire payload frame_ptr_next = output_udp_length_reg; output_udp_payload_tkeep_int = input_ip_payload_tkeep & count2keep(output_udp_length_reg - frame_ptr_reg); if (input_ip_payload_tlast) begin input_ip_payload_tready_next = 1'b0; input_ip_hdr_ready_next = ~output_udp_hdr_valid_reg; state_next = STATE_IDLE; end else begin store_last_word = 1'b1; output_udp_payload_tvalid_int = 1'b0; state_next = STATE_READ_PAYLOAD_LAST; end end else begin if (input_ip_payload_tlast) begin // end of frame, but length does not match error_payload_early_termination_next = 1'b1; output_udp_payload_tuser_int = 1'b1; input_ip_payload_tready_next = 1'b0; input_ip_hdr_ready_next = ~output_udp_hdr_valid_reg; state_next = STATE_IDLE; end else begin state_next = STATE_READ_PAYLOAD; end end end else begin state_next = STATE_READ_PAYLOAD; end end STATE_READ_PAYLOAD_LAST: begin // read and discard until end of frame input_ip_payload_tready_next = output_udp_payload_tready_int_early; output_udp_payload_tdata_int = last_word_data_reg; output_udp_payload_tkeep_int = last_word_keep_reg; output_udp_payload_tvalid_int = input_ip_payload_tvalid & input_ip_payload_tlast; output_udp_payload_tlast_int = input_ip_payload_tlast; output_udp_payload_tuser_int = input_ip_payload_tuser; if (input_ip_payload_tready & input_ip_payload_tvalid) begin if (input_ip_payload_tlast) begin input_ip_hdr_ready_next = ~output_udp_hdr_valid_reg; input_ip_payload_tready_next = 1'b0; state_next = STATE_IDLE; end else begin state_next = STATE_READ_PAYLOAD_LAST; end end else begin state_next = STATE_READ_PAYLOAD_LAST; end end STATE_WAIT_LAST: begin // wait for end of frame; read and discard input_ip_payload_tready_next = 1'b1; if (input_ip_payload_tready & input_ip_payload_tvalid) begin if (input_ip_payload_tlast) begin input_ip_hdr_ready_next = ~output_udp_hdr_valid_reg; input_ip_payload_tready_next = 1'b0; state_next = STATE_IDLE; end else begin state_next = STATE_WAIT_LAST; end end else begin state_next = STATE_WAIT_LAST; end end endcase end always @(posedge clk) begin if (rst) begin state_reg <= STATE_IDLE; frame_ptr_reg <= 16'd0; input_ip_hdr_ready_reg <= 1'b0; input_ip_payload_tready_reg <= 1'b0; output_udp_hdr_valid_reg <= 1'b0; busy_reg <= 1'b0; error_header_early_termination_reg <= 1'b0; error_payload_early_termination_reg <= 1'b0; end else begin state_reg <= state_next; frame_ptr_reg <= frame_ptr_next; input_ip_hdr_ready_reg <= input_ip_hdr_ready_next; input_ip_payload_tready_reg <= input_ip_payload_tready_next; output_udp_hdr_valid_reg <= output_udp_hdr_valid_next; error_header_early_termination_reg <= error_header_early_termination_next; error_payload_early_termination_reg <= error_payload_early_termination_next; busy_reg <= state_next != STATE_IDLE; end // datapath if (store_ip_hdr) begin output_eth_dest_mac_reg <= input_eth_dest_mac; output_eth_src_mac_reg <= input_eth_src_mac; output_eth_type_reg <= input_eth_type; output_ip_version_reg <= input_ip_version; output_ip_ihl_reg <= input_ip_ihl; output_ip_dscp_reg <= input_ip_dscp; output_ip_ecn_reg <= input_ip_ecn; output_ip_length_reg <= input_ip_length; output_ip_identification_reg <= input_ip_identification; output_ip_flags_reg <= input_ip_flags; output_ip_fragment_offset_reg <= input_ip_fragment_offset; output_ip_ttl_reg <= input_ip_ttl; output_ip_protocol_reg <= input_ip_protocol; output_ip_header_checksum_reg <= input_ip_header_checksum; output_ip_source_ip_reg <= input_ip_source_ip; output_ip_dest_ip_reg <= input_ip_dest_ip; end if (store_last_word) begin last_word_data_reg <= output_udp_payload_tdata_int; last_word_keep_reg <= output_udp_payload_tkeep_int; end if (store_hdr_word_0) begin output_udp_source_port_reg[15: 8] <= input_ip_payload_tdata[ 7: 0]; output_udp_source_port_reg[ 7: 0] <= input_ip_payload_tdata[15: 8]; output_udp_dest_port_reg[15: 8] <= input_ip_payload_tdata[23:16]; output_udp_dest_port_reg[ 7: 0] <= input_ip_payload_tdata[31:24]; output_udp_length_reg[15: 8] <= input_ip_payload_tdata[39:32]; output_udp_length_reg[ 7: 0] <= input_ip_payload_tdata[47:40]; output_udp_checksum_reg[15: 8] <= input_ip_payload_tdata[55:48]; output_udp_checksum_reg[ 7: 0] <= input_ip_payload_tdata[63:56]; end end // output datapath logic reg [63:0] output_udp_payload_tdata_reg = 64'd0; reg [7:0] output_udp_payload_tkeep_reg = 8'd0; reg output_udp_payload_tvalid_reg = 1'b0, output_udp_payload_tvalid_next; reg output_udp_payload_tlast_reg = 1'b0; reg output_udp_payload_tuser_reg = 1'b0; reg [63:0] temp_udp_payload_tdata_reg = 64'd0; reg [7:0] temp_udp_payload_tkeep_reg = 8'd0; reg temp_udp_payload_tvalid_reg = 1'b0, temp_udp_payload_tvalid_next; reg temp_udp_payload_tlast_reg = 1'b0; reg temp_udp_payload_tuser_reg = 1'b0; // datapath control reg store_udp_payload_int_to_output; reg store_udp_payload_int_to_temp; reg store_udp_payload_temp_to_output; assign output_udp_payload_tdata = output_udp_payload_tdata_reg; assign output_udp_payload_tkeep = output_udp_payload_tkeep_reg; assign output_udp_payload_tvalid = output_udp_payload_tvalid_reg; assign output_udp_payload_tlast = output_udp_payload_tlast_reg; assign output_udp_payload_tuser = output_udp_payload_tuser_reg; // enable ready input next cycle if output is ready or the temp reg will not be filled on the next cycle (output reg empty or no input) assign output_udp_payload_tready_int_early = output_udp_payload_tready | (~temp_udp_payload_tvalid_reg & (~output_udp_payload_tvalid_reg | ~output_udp_payload_tvalid_int)); always @* begin // transfer sink ready state to source output_udp_payload_tvalid_next = output_udp_payload_tvalid_reg; temp_udp_payload_tvalid_next = temp_udp_payload_tvalid_reg; store_udp_payload_int_to_output = 1'b0; store_udp_payload_int_to_temp = 1'b0; store_udp_payload_temp_to_output = 1'b0; if (output_udp_payload_tready_int_reg) begin // input is ready if (output_udp_payload_tready | ~output_udp_payload_tvalid_reg) begin // output is ready or currently not valid, transfer data to output output_udp_payload_tvalid_next = output_udp_payload_tvalid_int; store_udp_payload_int_to_output = 1'b1; end else begin // output is not ready, store input in temp temp_udp_payload_tvalid_next = output_udp_payload_tvalid_int; store_udp_payload_int_to_temp = 1'b1; end end else if (output_udp_payload_tready) begin // input is not ready, but output is ready output_udp_payload_tvalid_next = temp_udp_payload_tvalid_reg; temp_udp_payload_tvalid_next = 1'b0; store_udp_payload_temp_to_output = 1'b1; end end always @(posedge clk) begin if (rst) begin output_udp_payload_tvalid_reg <= 1'b0; output_udp_payload_tready_int_reg <= 1'b0; temp_udp_payload_tvalid_reg <= 1'b0; end else begin output_udp_payload_tvalid_reg <= output_udp_payload_tvalid_next; output_udp_payload_tready_int_reg <= output_udp_payload_tready_int_early; temp_udp_payload_tvalid_reg <= temp_udp_payload_tvalid_next; end // datapath if (store_udp_payload_int_to_output) begin output_udp_payload_tdata_reg <= output_udp_payload_tdata_int; output_udp_payload_tkeep_reg <= output_udp_payload_tkeep_int; output_udp_payload_tlast_reg <= output_udp_payload_tlast_int; output_udp_payload_tuser_reg <= output_udp_payload_tuser_int; end else if (store_udp_payload_temp_to_output) begin output_udp_payload_tdata_reg <= temp_udp_payload_tdata_reg; output_udp_payload_tkeep_reg <= temp_udp_payload_tkeep_reg; output_udp_payload_tlast_reg <= temp_udp_payload_tlast_reg; output_udp_payload_tuser_reg <= temp_udp_payload_tuser_reg; end if (store_udp_payload_int_to_temp) begin temp_udp_payload_tdata_reg <= output_udp_payload_tdata_int; temp_udp_payload_tkeep_reg <= output_udp_payload_tkeep_int; temp_udp_payload_tlast_reg <= output_udp_payload_tlast_int; temp_udp_payload_tuser_reg <= output_udp_payload_tuser_int; end end endmodule