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eth: Add 32-bit AXI stream BASE-R TX module and testbench

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Signed-off-by: Alex Forencich <alex@alexforencich.com>
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Alex Forencich
2025-06-17 20:14:30 -07:00
parent 6f5adb1b41
commit ebb8bf0bd4
5 changed files with 1586 additions and 0 deletions
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// SPDX-License-Identifier: CERN-OHL-S-2.0
/*
Copyright (c) 2025 FPGA Ninja, LLC
Authors:
- Alex Forencich
*/
`resetall
`timescale 1ns / 1ps
`default_nettype none
/*
* AXI4-Stream 10GBASE-R frame transmitter (AXI in, 10GBASE-R out)
*/
module taxi_axis_baser_tx_32 #
(
parameter DATA_W = 32,
parameter HDR_W = 2,
parameter logic GBX_IF_EN = 1'b0,
parameter GBX_CNT = 1,
parameter logic PADDING_EN = 1'b1,
parameter logic DIC_EN = 1'b1,
parameter MIN_FRAME_LEN = 64,
parameter logic PTP_TS_EN = 1'b0,
parameter PTP_TS_W = 96,
parameter logic TX_CPL_CTRL_IN_TUSER = 1'b1
)
(
input wire logic clk,
input wire logic rst,
/*
* Transmit interface (AXI stream)
*/
taxi_axis_if.snk s_axis_tx,
taxi_axis_if.src m_axis_tx_cpl,
/*
* 10GBASE-R encoded interface
*/
output wire logic [DATA_W-1:0] encoded_tx_data,
output wire logic encoded_tx_data_valid,
output wire logic [HDR_W-1:0] encoded_tx_hdr,
output wire logic encoded_tx_hdr_valid,
input wire logic [GBX_CNT-1:0] tx_gbx_req_sync = '0,
input wire logic tx_gbx_req_stall = '0,
output wire logic [GBX_CNT-1:0] tx_gbx_sync,
/*
* PTP
*/
input wire logic [PTP_TS_W-1:0] ptp_ts,
/*
* Configuration
*/
input wire logic [15:0] cfg_tx_max_pkt_len = 16'd1518,
input wire logic [7:0] cfg_tx_ifg = 8'd12,
input wire logic cfg_tx_enable,
/*
* Status
*/
output wire logic tx_start_packet,
output wire logic [2:0] stat_tx_byte,
output wire logic [15:0] stat_tx_pkt_len,
output wire logic stat_tx_pkt_ucast,
output wire logic stat_tx_pkt_mcast,
output wire logic stat_tx_pkt_bcast,
output wire logic stat_tx_pkt_vlan,
output wire logic stat_tx_pkt_good,
output wire logic stat_tx_pkt_bad,
output wire logic stat_tx_err_oversize,
output wire logic stat_tx_err_user,
output wire logic stat_tx_err_underflow
);
// extract parameters
localparam KEEP_W = DATA_W/8;
localparam USER_W = TX_CPL_CTRL_IN_TUSER ? 2 : 1;
localparam TX_TAG_W = s_axis_tx.ID_W;
localparam EMPTY_W = $clog2(KEEP_W);
localparam MIN_LEN_W = $clog2(MIN_FRAME_LEN-4-KEEP_W+1);
// check configuration
if (DATA_W != 32)
$fatal(0, "Error: Interface width must be 32 (instance %m)");
if (KEEP_W*8 != DATA_W)
$fatal(0, "Error: Interface requires byte (8-bit) granularity (instance %m)");
if (HDR_W != 2)
$fatal(0, "Error: HDR_W must be 2 (instance %m)");
if (s_axis_tx.DATA_W != DATA_W)
$fatal(0, "Error: Interface DATA_W parameter mismatch (instance %m)");
if (s_axis_tx.USER_W != USER_W)
$fatal(0, "Error: Interface USER_W parameter mismatch (instance %m)");
localparam [7:0]
ETH_PRE = 8'h55,
ETH_SFD = 8'hD5;
localparam [6:0]
CTRL_IDLE = 7'h00,
CTRL_LPI = 7'h06,
CTRL_ERROR = 7'h1e,
CTRL_RES_0 = 7'h2d,
CTRL_RES_1 = 7'h33,
CTRL_RES_2 = 7'h4b,
CTRL_RES_3 = 7'h55,
CTRL_RES_4 = 7'h66,
CTRL_RES_5 = 7'h78;
localparam [3:0]
O_SEQ_OS = 4'h0,
O_SIG_OS = 4'hf;
localparam [1:0]
SYNC_DATA = 2'b10,
SYNC_CTRL = 2'b01;
localparam [7:0]
BLOCK_TYPE_CTRL = 8'h1e, // C7 C6 C5 C4 C3 C2 C1 C0 BT
BLOCK_TYPE_OS_4 = 8'h2d, // D7 D6 D5 O4 C3 C2 C1 C0 BT
BLOCK_TYPE_START_4 = 8'h33, // D7 D6 D5 C3 C2 C1 C0 BT
BLOCK_TYPE_OS_START = 8'h66, // D7 D6 D5 O0 D3 D2 D1 BT
BLOCK_TYPE_OS_04 = 8'h55, // D7 D6 D5 O4 O0 D3 D2 D1 BT
BLOCK_TYPE_START_0 = 8'h78, // D7 D6 D5 D4 D3 D2 D1 BT
BLOCK_TYPE_OS_0 = 8'h4b, // C7 C6 C5 C4 O0 D3 D2 D1 BT
BLOCK_TYPE_TERM_0 = 8'h87, // C7 C6 C5 C4 C3 C2 C1 BT
BLOCK_TYPE_TERM_1 = 8'h99, // C7 C6 C5 C4 C3 C2 D0 BT
BLOCK_TYPE_TERM_2 = 8'haa, // C7 C6 C5 C4 C3 D1 D0 BT
BLOCK_TYPE_TERM_3 = 8'hb4, // C7 C6 C5 C4 D2 D1 D0 BT
BLOCK_TYPE_TERM_4 = 8'hcc, // C7 C6 C5 D3 D2 D1 D0 BT
BLOCK_TYPE_TERM_5 = 8'hd2, // C7 C6 D4 D3 D2 D1 D0 BT
BLOCK_TYPE_TERM_6 = 8'he1, // C7 D5 D4 D3 D2 D1 D0 BT
BLOCK_TYPE_TERM_7 = 8'hff; // D6 D5 D4 D3 D2 D1 D0 BT
localparam [2:0]
OUTPUT_TYPE_IDLE = 3'd0,
OUTPUT_TYPE_ERROR = 3'd1,
OUTPUT_TYPE_START = 3'd2,
OUTPUT_TYPE_DATA = 3'd3,
OUTPUT_TYPE_TERM_0 = 3'd4,
OUTPUT_TYPE_TERM_1 = 3'd5,
OUTPUT_TYPE_TERM_2 = 3'd6,
OUTPUT_TYPE_TERM_3 = 3'd7;
localparam [3:0]
STATE_IDLE = 4'd0,
STATE_PREAMBLE = 4'd1,
STATE_PAYLOAD = 4'd2,
STATE_PAD = 4'd3,
STATE_FCS_1 = 4'd4,
STATE_FCS_2 = 4'd5,
STATE_FCS_3 = 4'd6,
STATE_ERR = 4'd7,
STATE_IFG = 4'd8;
logic [3:0] state_reg = STATE_IDLE, state_next;
// datapath control signals
logic reset_crc;
logic update_crc;
logic [DATA_W-1:0] s_tdata_reg = '0, s_tdata_next;
logic [EMPTY_W-1:0] s_empty_reg = '0, s_empty_next;
logic [DATA_W-1:0] fcs_output_data_0;
logic [DATA_W-1:0] fcs_output_data_1;
logic [2:0] fcs_output_type_0;
logic [2:0] fcs_output_type_1;
logic [7:0] ifg_offset;
logic extra_cycle;
logic frame_reg = 1'b0, frame_next;
logic frame_error_reg = 1'b0, frame_error_next;
logic frame_oversize_reg = 1'b0, frame_oversize_next;
logic [MIN_LEN_W-1:0] frame_min_count_reg = '0, frame_min_count_next;
logic [2:0] hdr_ptr_reg = '0, hdr_ptr_next;
logic is_mcast_reg = 1'b0, is_mcast_next;
logic is_bcast_reg = 1'b0, is_bcast_next;
logic is_8021q_reg = 1'b0, is_8021q_next;
logic [15:0] frame_len_reg = '0, frame_len_next;
logic [15:0] frame_len_lim_reg = '0, frame_len_lim_next;
logic [7:0] ifg_cnt_reg = '0, ifg_cnt_next;
logic [7:0] ifg_count_reg = 8'd0, ifg_count_next;
logic [1:0] deficit_idle_count_reg = 2'd0, deficit_idle_count_next;
logic s_axis_tx_tready_reg = 1'b0, s_axis_tx_tready_next;
logic [PTP_TS_W-1:0] m_axis_tx_cpl_ts_reg = '0, m_axis_tx_cpl_ts_next;
logic [TX_TAG_W-1:0] m_axis_tx_cpl_tag_reg = '0, m_axis_tx_cpl_tag_next;
logic m_axis_tx_cpl_valid_reg = 1'b0, m_axis_tx_cpl_valid_next;
logic [31:0] crc_state_reg[3:0];
wire [31:0] crc_state_next[3:0];
logic [DATA_W-1:0] encoded_tx_data_reg = {24'd0, BLOCK_TYPE_CTRL};
logic encoded_tx_data_valid_reg = 1'b0;
logic [HDR_W-1:0] encoded_tx_hdr_reg = SYNC_CTRL;
logic encoded_tx_hdr_valid_reg = 1'b0;
logic phase_reg = 1'b0;
logic [GBX_CNT-1:0] tx_gbx_sync_reg = '0;
logic [DATA_W-1:0] output_data_reg = '0, output_data_next;
logic [DATA_W-1:0] output_data_d1_reg = '0;
logic [2:0] output_type_reg = OUTPUT_TYPE_IDLE, output_type_next;
logic start_packet_reg = 1'b0, start_packet_next;
logic [2:0] stat_tx_byte_reg = '0, stat_tx_byte_next;
logic [15:0] stat_tx_pkt_len_reg = '0, stat_tx_pkt_len_next;
logic stat_tx_pkt_ucast_reg = 1'b0, stat_tx_pkt_ucast_next;
logic stat_tx_pkt_mcast_reg = 1'b0, stat_tx_pkt_mcast_next;
logic stat_tx_pkt_bcast_reg = 1'b0, stat_tx_pkt_bcast_next;
logic stat_tx_pkt_vlan_reg = 1'b0, stat_tx_pkt_vlan_next;
logic stat_tx_pkt_good_reg = 1'b0, stat_tx_pkt_good_next;
logic stat_tx_pkt_bad_reg = 1'b0, stat_tx_pkt_bad_next;
logic stat_tx_err_oversize_reg = 1'b0, stat_tx_err_oversize_next;
logic stat_tx_err_user_reg = 1'b0, stat_tx_err_user_next;
logic stat_tx_err_underflow_reg = 1'b0, stat_tx_err_underflow_next;
assign s_axis_tx.tready = s_axis_tx_tready_reg && (!GBX_IF_EN || !tx_gbx_req_stall);
assign encoded_tx_data = encoded_tx_data_reg;
assign encoded_tx_data_valid = GBX_IF_EN ? encoded_tx_data_valid_reg : 1'b1;
assign encoded_tx_hdr = encoded_tx_hdr_reg;
assign encoded_tx_hdr_valid = encoded_tx_hdr_valid_reg;
assign tx_gbx_sync = GBX_IF_EN ? tx_gbx_sync_reg : '0;
assign m_axis_tx_cpl.tdata = PTP_TS_EN ? m_axis_tx_cpl_ts_reg : '0;
assign m_axis_tx_cpl.tkeep = 1'b1;
assign m_axis_tx_cpl.tstrb = m_axis_tx_cpl.tkeep;
assign m_axis_tx_cpl.tvalid = m_axis_tx_cpl_valid_reg;
assign m_axis_tx_cpl.tlast = 1'b1;
assign m_axis_tx_cpl.tid = m_axis_tx_cpl_tag_reg;
assign m_axis_tx_cpl.tdest = '0;
assign m_axis_tx_cpl.tuser = '0;
assign tx_start_packet = start_packet_reg;
assign stat_tx_byte = stat_tx_byte_reg;
assign stat_tx_pkt_len = stat_tx_pkt_len_reg;
assign stat_tx_pkt_ucast = stat_tx_pkt_ucast_reg;
assign stat_tx_pkt_mcast = stat_tx_pkt_mcast_reg;
assign stat_tx_pkt_bcast = stat_tx_pkt_bcast_reg;
assign stat_tx_pkt_vlan = stat_tx_pkt_vlan_reg;
assign stat_tx_pkt_good = stat_tx_pkt_good_reg;
assign stat_tx_pkt_bad = stat_tx_pkt_bad_reg;
assign stat_tx_err_oversize = stat_tx_err_oversize_reg;
assign stat_tx_err_user = stat_tx_err_user_reg;
assign stat_tx_err_underflow = stat_tx_err_underflow_reg;
for (genvar n = 0; n < 4; n = n + 1) begin : crc
taxi_lfsr #(
.LFSR_W(32),
.LFSR_POLY(32'h4c11db7),
.LFSR_GALOIS(1),
.LFSR_FEED_FORWARD(0),
.REVERSE(1),
.DATA_W(8*(n+1)),
.DATA_IN_EN(1'b1),
.DATA_OUT_EN(1'b0)
)
eth_crc (
.data_in(s_tdata_reg[0 +: 8*(n+1)]),
.state_in(crc_state_reg[3]),
.data_out(),
.state_out(crc_state_next[n])
);
end
function [1:0] keep2empty(input [3:0] k);
casez (k)
4'bzzz0: keep2empty = 2'd3;
4'bzz01: keep2empty = 2'd3;
4'bz011: keep2empty = 2'd2;
4'b0111: keep2empty = 2'd1;
4'b1111: keep2empty = 2'd0;
endcase
endfunction
// Mask input data
wire [DATA_W-1:0] s_axis_tx_tdata_masked;
for (genvar n = 0; n < KEEP_W; n = n + 1) begin
assign s_axis_tx_tdata_masked[n*8 +: 8] = s_axis_tx.tkeep[n] ? s_axis_tx.tdata[n*8 +: 8] : 8'd0;
end
// FCS cycle calculation
always_comb begin
casez (s_empty_reg)
2'd3: begin
fcs_output_data_0 = {~crc_state_next[0][23:0], s_tdata_reg[7:0]};
fcs_output_data_1 = {24'd0, ~crc_state_reg[0][31:24]};
fcs_output_type_0 = OUTPUT_TYPE_DATA;
fcs_output_type_1 = OUTPUT_TYPE_TERM_1;
ifg_offset = 8'd3;
extra_cycle = 1'b0;
end
2'd2: begin
fcs_output_data_0 = {~crc_state_next[1][15:0], s_tdata_reg[15:0]};
fcs_output_data_1 = {16'd0, ~crc_state_reg[1][31:16]};
fcs_output_type_0 = OUTPUT_TYPE_DATA;
fcs_output_type_1 = OUTPUT_TYPE_TERM_2;
ifg_offset = 8'd2;
extra_cycle = 1'b0;
end
2'd1: begin
fcs_output_data_0 = {~crc_state_next[2][7:0], s_tdata_reg[23:0]};
fcs_output_data_1 = {8'd0, ~crc_state_reg[2][31:8]};
fcs_output_type_0 = OUTPUT_TYPE_DATA;
fcs_output_type_1 = OUTPUT_TYPE_TERM_3;
ifg_offset = 8'd1;
extra_cycle = 1'b0;
end
2'd0: begin
fcs_output_data_0 = s_tdata_reg;
fcs_output_data_1 = ~crc_state_reg[3];
fcs_output_type_0 = OUTPUT_TYPE_DATA;
fcs_output_type_1 = OUTPUT_TYPE_DATA;
ifg_offset = 8'd4;
extra_cycle = 1'b1;
end
endcase
end
always_comb begin
state_next = STATE_IDLE;
reset_crc = 1'b0;
update_crc = 1'b0;
frame_next = frame_reg;
frame_error_next = frame_error_reg;
frame_oversize_next = frame_oversize_reg;
frame_min_count_next = frame_min_count_reg;
hdr_ptr_next = hdr_ptr_reg;
is_mcast_next = is_mcast_reg;
is_bcast_next = is_bcast_reg;
is_8021q_next = is_8021q_reg;
frame_len_next = frame_len_reg;
frame_len_lim_next = frame_len_lim_reg;
ifg_cnt_next = ifg_cnt_reg;
ifg_count_next = ifg_count_reg;
deficit_idle_count_next = deficit_idle_count_reg;
s_axis_tx_tready_next = 1'b0;
s_tdata_next = s_tdata_reg;
s_empty_next = s_empty_reg;
m_axis_tx_cpl_ts_next = m_axis_tx_cpl_ts_reg;
m_axis_tx_cpl_tag_next = m_axis_tx_cpl_tag_reg;
m_axis_tx_cpl_valid_next = 1'b0;
if (start_packet_reg) begin
if (PTP_TS_EN) begin
m_axis_tx_cpl_ts_next = ptp_ts;
end
m_axis_tx_cpl_tag_next = s_axis_tx.tid;
if (TX_CPL_CTRL_IN_TUSER) begin
m_axis_tx_cpl_valid_next = (s_axis_tx.tuser >> 1) == 0;
end else begin
m_axis_tx_cpl_valid_next = 1'b1;
end
end
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_IDLE;
start_packet_next = 1'b0;
stat_tx_byte_next = '0;
stat_tx_pkt_len_next = '0;
stat_tx_pkt_ucast_next = 1'b0;
stat_tx_pkt_mcast_next = 1'b0;
stat_tx_pkt_bcast_next = 1'b0;
stat_tx_pkt_vlan_next = 1'b0;
stat_tx_pkt_good_next = 1'b0;
stat_tx_pkt_bad_next = 1'b0;
stat_tx_err_oversize_next = 1'b0;
stat_tx_err_user_next = 1'b0;
stat_tx_err_underflow_next = 1'b0;
if (s_axis_tx.tvalid && s_axis_tx.tready) begin
frame_next = !s_axis_tx.tlast;
end
if (GBX_IF_EN && tx_gbx_req_stall) begin
// gearbox stall - hold state
state_next = state_reg;
s_axis_tx_tready_next = s_axis_tx_tready_reg;
end else begin
// counter for min frame length enforcement
if (frame_min_count_reg > MIN_LEN_W'(KEEP_W)) begin
frame_min_count_next = MIN_LEN_W'(frame_min_count_reg - KEEP_W);
end else begin
frame_min_count_next = 0;
end
// counter to measure frame length
if (&frame_len_reg[15:2] == 0) begin
frame_len_next = frame_len_reg + 16'(KEEP_W);
end else begin
frame_len_next = '1;
end
// counter for max frame length enforcement
if (frame_len_lim_reg[15:2] != 0) begin
frame_len_lim_next = frame_len_lim_reg - 16'(KEEP_W);
end else begin
frame_len_lim_next = '0;
end
// address and ethertype checks
if (&hdr_ptr_reg == 0) begin
hdr_ptr_next = hdr_ptr_reg + 1;
end
case (hdr_ptr_reg)
3'd0: begin
is_mcast_next = s_tdata_reg[0];
is_bcast_next = &s_tdata_reg;
end
3'd1: is_bcast_next = is_bcast_reg && &s_tdata_reg[15:0];
3'd3: is_8021q_next = {s_tdata_reg[7:0], s_tdata_reg[15:8]} == 16'h8100;
default: begin
// do nothing
end
endcase
if (ifg_cnt_reg[7:2] != 0) begin
ifg_cnt_next = ifg_cnt_reg - 8'(KEEP_W);
end else begin
ifg_cnt_next = '0;
end
case (state_reg)
STATE_IDLE: begin
// idle state - wait for data
frame_error_next = 1'b0;
frame_min_count_next = MIN_LEN_W'(MIN_FRAME_LEN-4-KEEP_W);
hdr_ptr_next = 0;
frame_len_next = 0;
frame_len_lim_next = cfg_tx_max_pkt_len;
reset_crc = 1'b1;
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_IDLE;
s_tdata_next = s_axis_tx_tdata_masked;
s_empty_next = keep2empty(s_axis_tx.tkeep);
if (s_axis_tx.tvalid && cfg_tx_enable) begin
// Preamble and SFD
output_data_next = {4{ETH_PRE}};
output_type_next = OUTPUT_TYPE_START;
s_axis_tx_tready_next = 1'b1;
state_next = STATE_PREAMBLE;
end else begin
ifg_count_next = 8'd0;
deficit_idle_count_next = 2'd0;
state_next = STATE_IDLE;
end
end
STATE_PREAMBLE: begin
// send preamble
reset_crc = 1'b1;
hdr_ptr_next = 0;
frame_len_next = 0;
frame_len_lim_next = cfg_tx_max_pkt_len;
s_tdata_next = s_axis_tx_tdata_masked;
s_empty_next = keep2empty(s_axis_tx.tkeep);
output_data_next = {ETH_SFD, {3{ETH_PRE}}};
output_type_next = OUTPUT_TYPE_DATA;
s_axis_tx_tready_next = 1'b1;
start_packet_next = 1'b1;
state_next = STATE_PAYLOAD;
end
STATE_PAYLOAD: begin
// transfer payload
update_crc = 1'b1;
s_axis_tx_tready_next = 1'b1;
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_DATA;
s_tdata_next = s_axis_tx_tdata_masked;
s_empty_next = keep2empty(s_axis_tx.tkeep);
stat_tx_byte_next = 3'(KEEP_W);
if (s_axis_tx.tvalid && s_axis_tx.tlast) begin
frame_oversize_next = frame_len_lim_reg < 16'(4+4+4-keep2empty(s_axis_tx.tkeep));
end else begin
frame_oversize_next = frame_len_lim_reg < 4+4;
end
if (!s_axis_tx.tvalid || s_axis_tx.tlast || frame_oversize_next) begin
s_axis_tx_tready_next = frame_next; // drop frame
frame_error_next = !s_axis_tx.tvalid || s_axis_tx.tuser[0] || frame_oversize_next;
stat_tx_err_user_next = s_axis_tx.tuser[0];
stat_tx_err_underflow_next = !s_axis_tx.tvalid;
if (PADDING_EN && frame_min_count_reg != 0) begin
if (frame_min_count_reg > MIN_LEN_W'(KEEP_W)) begin
s_empty_next = 0;
state_next = STATE_PAD;
end else begin
if (keep2empty(s_axis_tx.tkeep) > 2'(KEEP_W-frame_min_count_reg)) begin
s_empty_next = 2'(KEEP_W-frame_min_count_reg);
end
state_next = STATE_FCS_1;
end
end else begin
state_next = STATE_FCS_1;
end
end else begin
state_next = STATE_PAYLOAD;
end
end
STATE_PAD: begin
// pad frame to MIN_FRAME_LEN
s_axis_tx_tready_next = frame_next; // drop frame
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_DATA;
s_tdata_next = 32'd0;
s_empty_next = 0;
stat_tx_byte_next = 3'(KEEP_W);
update_crc = 1'b1;
if (frame_min_count_reg > MIN_LEN_W'(KEEP_W)) begin
state_next = STATE_PAD;
end else begin
s_empty_next = 2'(KEEP_W-frame_min_count_reg);
state_next = STATE_FCS_1;
end
end
STATE_FCS_1: begin
// last cycle
s_axis_tx_tready_next = frame_next; // drop frame
output_data_next = fcs_output_data_0;
output_type_next = fcs_output_type_0;
stat_tx_byte_next = 3'(KEEP_W);
update_crc = 1'b1;
ifg_count_next = (cfg_tx_ifg > 8'd12 ? cfg_tx_ifg : 8'd12) - ifg_offset + 8'(deficit_idle_count_reg);
if (frame_error_reg) begin
state_next = STATE_ERR;
end else begin
state_next = STATE_FCS_2;
end
end
STATE_FCS_2: begin
// last cycle
s_axis_tx_tready_next = frame_next; // drop frame
output_data_next = fcs_output_data_1;
output_type_next = fcs_output_type_1;
stat_tx_byte_next = 4-s_empty_reg;
frame_len_next = frame_len_reg + 16'(4-s_empty_reg);
if (extra_cycle) begin
state_next = STATE_FCS_3;
end else begin
stat_tx_pkt_len_next = frame_len_next;
stat_tx_pkt_good_next = !frame_error_reg;
stat_tx_pkt_bad_next = frame_error_reg;
stat_tx_pkt_ucast_next = !is_mcast_reg;
stat_tx_pkt_mcast_next = is_mcast_reg && !is_bcast_reg;
stat_tx_pkt_bcast_next = is_bcast_reg;
stat_tx_pkt_vlan_next = is_8021q_reg;
stat_tx_err_oversize_next = frame_oversize_reg;
state_next = STATE_IFG;
end
end
STATE_FCS_3: begin
// last cycle
s_axis_tx_tready_next = frame_next; // drop frame
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_TERM_0;
stat_tx_pkt_len_next = frame_len_reg;
stat_tx_pkt_good_next = !frame_error_reg;
stat_tx_pkt_bad_next = frame_error_reg;
stat_tx_pkt_ucast_next = !is_mcast_reg;
stat_tx_pkt_mcast_next = is_mcast_reg && !is_bcast_reg;
stat_tx_pkt_bcast_next = is_bcast_reg;
stat_tx_pkt_vlan_next = is_8021q_reg;
stat_tx_err_oversize_next = frame_oversize_reg;
if (DIC_EN) begin
if (ifg_count_next > 8'd3) begin
state_next = STATE_IFG;
end else begin
deficit_idle_count_next = 2'(ifg_count_next);
ifg_count_next = 8'd0;
s_axis_tx_tready_next = 1'b1;
state_next = STATE_IDLE;
end
end else begin
if (ifg_count_next > 8'd0) begin
state_next = STATE_IFG;
end else begin
state_next = STATE_IDLE;
end
end
end
STATE_ERR: begin
// terminate packet with error
s_axis_tx_tready_next = frame_next; // drop frame
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_ERROR;
ifg_count_next = cfg_tx_ifg > 8'd12 ? cfg_tx_ifg : 8'd12;
stat_tx_pkt_len_next = frame_len_reg;
stat_tx_pkt_good_next = !frame_error_reg;
stat_tx_pkt_bad_next = frame_error_reg;
stat_tx_pkt_ucast_next = !is_mcast_reg;
stat_tx_pkt_mcast_next = is_mcast_reg && !is_bcast_reg;
stat_tx_pkt_bcast_next = is_bcast_reg;
stat_tx_pkt_vlan_next = is_8021q_reg;
stat_tx_err_oversize_next = frame_oversize_reg;
state_next = STATE_IFG;
end
STATE_IFG: begin
// send IFG
s_axis_tx_tready_next = frame_next; // drop frame
output_data_next = s_tdata_reg;
output_type_next = OUTPUT_TYPE_IDLE;
if (ifg_count_reg > 8'd4) begin
ifg_count_next = ifg_count_reg - 8'd4;
end else begin
ifg_count_next = 8'd0;
end
if (DIC_EN) begin
if (ifg_count_next > 8'd3 || frame_reg) begin
state_next = STATE_IFG;
end else begin
deficit_idle_count_next = 2'(ifg_count_next);
ifg_count_next = 8'd0;
state_next = STATE_IDLE;
end
end else begin
if (ifg_count_next > 8'd0 || frame_reg) begin
state_next = STATE_IFG;
end else begin
state_next = STATE_IDLE;
end
end
end
default: begin
// invalid state, return to idle
state_next = STATE_IDLE;
end
endcase
end
end
always_ff @(posedge clk) begin
state_reg <= state_next;
frame_reg <= frame_next;
frame_error_reg <= frame_error_next;
frame_oversize_reg <= frame_oversize_next;
frame_min_count_reg <= frame_min_count_next;
hdr_ptr_reg <= hdr_ptr_next;
is_mcast_reg <= is_mcast_next;
is_bcast_reg <= is_bcast_next;
is_8021q_reg <= is_8021q_next;
frame_len_reg <= frame_len_next;
frame_len_lim_reg <= frame_len_lim_next;
ifg_cnt_reg <= ifg_cnt_next;
ifg_count_reg <= ifg_count_next;
deficit_idle_count_reg <= deficit_idle_count_next;
s_tdata_reg <= s_tdata_next;
s_empty_reg <= s_empty_next;
s_axis_tx_tready_reg <= s_axis_tx_tready_next;
m_axis_tx_cpl_ts_reg <= m_axis_tx_cpl_ts_next;
m_axis_tx_cpl_tag_reg <= m_axis_tx_cpl_tag_next;
m_axis_tx_cpl_valid_reg <= m_axis_tx_cpl_valid_next;
start_packet_reg <= start_packet_next;
stat_tx_byte_reg <= stat_tx_byte_next;
stat_tx_pkt_len_reg <= stat_tx_pkt_len_next;
stat_tx_pkt_ucast_reg <= stat_tx_pkt_ucast_next;
stat_tx_pkt_mcast_reg <= stat_tx_pkt_mcast_next;
stat_tx_pkt_bcast_reg <= stat_tx_pkt_bcast_next;
stat_tx_pkt_vlan_reg <= stat_tx_pkt_vlan_next;
stat_tx_pkt_good_reg <= stat_tx_pkt_good_next;
stat_tx_pkt_bad_reg <= stat_tx_pkt_bad_next;
stat_tx_err_oversize_reg <= stat_tx_err_oversize_next;
stat_tx_err_user_reg <= stat_tx_err_user_next;
stat_tx_err_underflow_reg <= stat_tx_err_underflow_next;
if (GBX_IF_EN && tx_gbx_req_stall) begin
// gearbox stall
encoded_tx_data_valid_reg <= 1'b0;
encoded_tx_hdr_valid_reg <= 1'b0;
end else begin
output_data_reg <= output_data_next;
output_type_reg <= output_type_next;
output_data_d1_reg <= output_data_reg;
if (phase_reg == 0) begin
case ({output_type_reg, output_type_next})
{OUTPUT_TYPE_IDLE, OUTPUT_TYPE_IDLE}: begin
encoded_tx_data_reg <= {24'd0, BLOCK_TYPE_CTRL};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_ERROR, OUTPUT_TYPE_ERROR}: begin
encoded_tx_data_reg <= {24'hc78f1e, BLOCK_TYPE_CTRL};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_START, OUTPUT_TYPE_DATA}: begin
encoded_tx_data_reg <= {output_data_reg[31:8], BLOCK_TYPE_START_0};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_IDLE, OUTPUT_TYPE_START}: begin
encoded_tx_data_reg <= {24'd0, BLOCK_TYPE_START_4};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_DATA, OUTPUT_TYPE_DATA}: begin
encoded_tx_data_reg <= output_data_reg;
encoded_tx_hdr_reg <= SYNC_DATA;
end
{OUTPUT_TYPE_TERM_0, OUTPUT_TYPE_IDLE}: begin
encoded_tx_data_reg <= {24'd0, BLOCK_TYPE_TERM_0};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_TERM_1, OUTPUT_TYPE_IDLE}: begin
encoded_tx_data_reg <= {16'd0, output_data_reg[7:0], BLOCK_TYPE_TERM_1};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_TERM_2, OUTPUT_TYPE_IDLE}: begin
encoded_tx_data_reg <= {8'd0, output_data_reg[15:0], BLOCK_TYPE_TERM_2};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_TERM_3, OUTPUT_TYPE_IDLE}: begin
encoded_tx_data_reg <= {output_data_reg[23:0], BLOCK_TYPE_TERM_3};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_DATA, OUTPUT_TYPE_TERM_0}: begin
encoded_tx_data_reg <= {output_data_reg[23:0], BLOCK_TYPE_TERM_4};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_DATA, OUTPUT_TYPE_TERM_1}: begin
encoded_tx_data_reg <= {output_data_reg[23:0], BLOCK_TYPE_TERM_5};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_DATA, OUTPUT_TYPE_TERM_2}: begin
encoded_tx_data_reg <= {output_data_reg[23:0], BLOCK_TYPE_TERM_6};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
{OUTPUT_TYPE_DATA, OUTPUT_TYPE_TERM_3}: begin
encoded_tx_data_reg <= {output_data_reg[23:0], BLOCK_TYPE_TERM_7};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
default: begin
encoded_tx_data_reg <= {24'hc78f1e, BLOCK_TYPE_CTRL};
encoded_tx_hdr_reg <= SYNC_CTRL;
end
endcase
end else begin
case (output_type_reg)
OUTPUT_TYPE_IDLE: begin
encoded_tx_data_reg <= 32'd0;
end
OUTPUT_TYPE_ERROR: begin
encoded_tx_data_reg <= 32'h3c78f1e3; // CTRL_ERROR
end
OUTPUT_TYPE_START: begin
encoded_tx_data_reg <= {output_data_reg[31:8], 8'd0};
end
OUTPUT_TYPE_DATA: begin
encoded_tx_data_reg <= output_data_reg;
end
OUTPUT_TYPE_TERM_0: begin
encoded_tx_data_reg <= {24'd0, output_data_d1_reg[31:24]};
end
OUTPUT_TYPE_TERM_1: begin
encoded_tx_data_reg <= {16'd0, output_data_reg[7:0], output_data_d1_reg[31:24]};
end
OUTPUT_TYPE_TERM_2: begin
encoded_tx_data_reg <= {8'd0, output_data_reg[15:0], output_data_d1_reg[31:24]};
end
OUTPUT_TYPE_TERM_3: begin
encoded_tx_data_reg <= {output_data_reg[23:0], output_data_d1_reg[31:24]};
end
default: begin
encoded_tx_data_reg <= 32'h3c78f1e3; // CTRL_ERROR
end
endcase
end
encoded_tx_data_valid_reg <= 1'b1;
encoded_tx_hdr_valid_reg <= phase_reg == 0;
phase_reg <= !phase_reg;
if (GBX_IF_EN && tx_gbx_req_sync[0]) begin
phase_reg <= 1'b1;
end
for (integer i = 0; i < 3; i = i + 1) begin
crc_state_reg[i] <= crc_state_next[i];
end
if (update_crc) begin
crc_state_reg[3] <= crc_state_next[3];
end
if (reset_crc) begin
crc_state_reg[3] <= '1;
end
end
tx_gbx_sync_reg <= tx_gbx_req_sync;
if (rst) begin
state_reg <= STATE_IDLE;
frame_reg <= 1'b0;
ifg_count_reg <= 8'd0;
deficit_idle_count_reg <= 2'd0;
s_axis_tx_tready_reg <= 1'b0;
m_axis_tx_cpl_valid_reg <= 1'b0;
encoded_tx_data_reg <= {24'd0, BLOCK_TYPE_CTRL};
encoded_tx_data_valid_reg <= 1'b0;
encoded_tx_hdr_reg <= SYNC_CTRL;
encoded_tx_hdr_valid_reg <= 1'b0;
phase_reg <= 1'b0;
tx_gbx_sync_reg <= '0;
output_type_reg <= OUTPUT_TYPE_IDLE;
start_packet_reg <= 1'b0;
stat_tx_byte_reg <= '0;
stat_tx_pkt_len_reg <= '0;
stat_tx_pkt_ucast_reg <= 1'b0;
stat_tx_pkt_mcast_reg <= 1'b0;
stat_tx_pkt_bcast_reg <= 1'b0;
stat_tx_pkt_vlan_reg <= 1'b0;
stat_tx_pkt_good_reg <= 1'b0;
stat_tx_pkt_bad_reg <= 1'b0;
stat_tx_err_oversize_reg <= 1'b0;
stat_tx_err_user_reg <= 1'b0;
stat_tx_err_underflow_reg <= 1'b0;
end
end
endmodule
`resetall