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Diffstat (limited to 'source/ipv4.v')
| -rw-r--r-- | source/ipv4.v | 152 |
1 files changed, 0 insertions, 152 deletions
diff --git a/source/ipv4.v b/source/ipv4.v deleted file mode 100644 index 55ab7a7..0000000 --- a/source/ipv4.v +++ /dev/null @@ -1,152 +0,0 @@ -/* - * ipv4.v - * - * Copyright (C) 2018, 2019 Mind Chasers Inc. - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - * - * function: Receive State Machine and Logic for IPv4 - * - * - * 0-7 8-15 16-23 24-31 - * 0 Version/IHL TOS Total Length............. - * 4 Identification...... Flags/Frag Off........... - * 8 TTL Protocol Header Checksum.......... - * 12 Source IP Address.................................... - * 16 Dest IP Address...................................... - * 20 Options / Padding.................................... - * - * - * When pkt_start is detected, rx_data_m2 has the first byte - */ - -`timescale 1ns /10ps - -module ipv4_rx ( - input rstn, - input clk, - - // control - input phy_resetn, - input phy_up, - - // packet data - input pkt_start, // assert for each new frame to start state machines - input rx_eop, // use as a synch reset - input[7:0] rx_data_m1, - input[7:0] rx_data_m2, - input[7:0] rx_data_m3, // first byte of packet appears here simultaneous with pkt_start - input[7:0] rx_data_m4, - - // flags - output pkt_complete, - output reg trigger_src_addr, - output reg trigger_dst_addr, - output reg keep - ); - - /* Byte Address (when last byte of field is present on rx_data_m1 ) */ - localparam IPV4_TOS=1, IPV4_LENGTH=3, IPV4_IP_ID=5, IPV4_PROTOCOL=9, - IPV4_HDR_CKSUM=11, IPV4_SRC_ADDR=15, IPV4_DST_ADDR=19; - - localparam RX_ST_IDLE=4'h0, RX_ST_DATA=4'h1, RX_ST_DONE=4'h2, RX_ST_3=4'h3, - RX_ST_4=4'h4, RX_ST_5=4'h5, RX_ST_6=4'h6, RX_ST_7=4'h7, - RX_ST_8=4'h8, RX_ST_9=4'h9, RX_ST_A=4'ha, RX_ST_B=4'hb, - RX_ST_C=4'hc, RX_ST_D=4'hd, RX_ST_E=4'he, RX_ST_F=4'hf; - - localparam IPV4_PROTO_ICMP = 1, IPV4_PROTO_IGMP = 2, IPV4_PROTO_TCP = 6, IPV4_PROTO_UDP = 17, - IPV4_PROTO_ENCAP = 41, IPV4_PROTO_OSPF = 89, IPV4_PROTO_SCTP = 132; - - - reg [3:0] rx_state; - reg [10:0] rx_byte_cnt; - reg [10:0] rx_pkt_length; - reg [7:0] protocol; - wire rx_error; - - /* - * rx_state machine - * capture an IPv4 Packet - * - */ - always @(posedge clk, negedge rstn) - if (!rstn) - rx_state <= RX_ST_IDLE; - else if ( rx_eop || !phy_resetn ) // EOP will reset state machine - rx_state <= RX_ST_IDLE; - else if ( phy_up ) - case ( rx_state ) - RX_ST_IDLE: if ( pkt_start ) // Found /S/ - rx_state <= RX_ST_DATA; - RX_ST_DATA: if (pkt_complete) - rx_state <= RX_ST_DONE; - RX_ST_DONE: rx_state <= RX_ST_IDLE; - endcase - else - rx_state <= RX_ST_IDLE; - - - /* rx_byte_cnt */ - always @(posedge clk, negedge rstn) - if (!rstn) - rx_byte_cnt <= 0; - else if ( rx_state == RX_ST_IDLE && !pkt_start ) // synch reset - rx_byte_cnt <= 1; - else if ( rx_state != RX_ST_IDLE || pkt_start ) - rx_byte_cnt <= rx_byte_cnt + 1; - - - /* protocol */ - always @(posedge clk, negedge rstn) - if ( !rstn ) - protocol <= 0; - else if ( rx_eop ) - protocol <= 0; - else if ( rx_byte_cnt == IPV4_PROTOCOL ) - protocol <= rx_data_m1; - - - /* rx_pkt_length */ - always @(posedge clk, negedge rstn) - if ( !rstn ) - rx_pkt_length <= 11'h7ff; - else if ( rx_eop ) - rx_pkt_length <= 11'h7ff; - else if ( rx_state == RX_ST_DATA && rx_byte_cnt == IPV4_LENGTH ) - rx_pkt_length <= { rx_data_m2[2:0], rx_data_m1 }; - - /* - * Packet Filter Trigger(s), assert the sample before the data appears - * - */ - always @(posedge clk, negedge rstn) - if (!rstn) - trigger_src_addr <= 1'b0; - else if ( rx_byte_cnt == IPV4_SRC_ADDR-1 ) - trigger_src_addr <= 1'b1; - else - trigger_src_addr <= 1'b0; - - always @(posedge clk, negedge rstn) - if (!rstn) - trigger_dst_addr <= 1'b0; - else if ( rx_byte_cnt == IPV4_DST_ADDR-1 ) - trigger_dst_addr <= 1'b1; - else - trigger_dst_addr <= 1'b0; - - assign pkt_complete = ( rx_state >= RX_ST_DATA && rx_pkt_length == rx_byte_cnt+1 ) ? 1 : 0; - assign rx_error = 0; - - -endmodule |
