1
0
mirror of https://github.com/corundum/corundum.git synced 2025-01-16 08:12:53 +08:00
corundum/rtl/mac_pause_ctrl_rx.v
Alex Forencich ba5a883433 Add pause/PFC modules
Signed-off-by: Alex Forencich <alex@alexforencich.com>
2023-07-23 16:31:33 -07:00

222 lines
7.3 KiB
Verilog

/*
Copyright (c) 2023 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
`resetall
`timescale 1ns / 1ps
`default_nettype none
/*
* PFC and pause frame receive handling
*/
module mac_pause_ctrl_rx #
(
parameter MCF_PARAMS_SIZE = 18,
parameter PFC_ENABLE = 1
)
(
input wire clk,
input wire rst,
/*
* MAC control frame interface
*/
input wire mcf_valid,
input wire [47:0] mcf_eth_dst,
input wire [47:0] mcf_eth_src,
input wire [15:0] mcf_eth_type,
input wire [15:0] mcf_opcode,
input wire [MCF_PARAMS_SIZE*8-1:0] mcf_params,
/*
* Link-level Flow Control (LFC) (IEEE 802.3 annex 31B PAUSE)
*/
input wire rx_lfc_en,
output wire rx_lfc_req,
input wire rx_lfc_ack,
/*
* Priority Flow Control (PFC) (IEEE 802.3 annex 31D PFC)
*/
input wire [7:0] rx_pfc_en,
output wire [7:0] rx_pfc_req,
input wire [7:0] rx_pfc_ack,
/*
* Configuration
*/
input wire [15:0] cfg_rx_lfc_opcode,
input wire cfg_rx_lfc_en,
input wire [15:0] cfg_rx_pfc_opcode,
input wire cfg_rx_pfc_en,
input wire [9:0] cfg_quanta_step,
input wire cfg_quanta_clk_en,
/*
* Status
*/
output wire stat_rx_lfc_pkt,
output wire stat_rx_lfc_xon,
output wire stat_rx_lfc_xoff,
output wire stat_rx_lfc_paused,
output wire stat_rx_pfc_pkt,
output wire [7:0] stat_rx_pfc_xon,
output wire [7:0] stat_rx_pfc_xoff,
output wire [7:0] stat_rx_pfc_paused
);
localparam QFB = 8;
// check configuration
initial begin
if (MCF_PARAMS_SIZE < (PFC_ENABLE ? 18 : 2)) begin
$error("Error: MCF_PARAMS_SIZE too small for requested configuration (instance %m)");
$finish;
end
end
reg lfc_req_reg = 1'b0, lfc_req_next;
reg [7:0] pfc_req_reg = 8'd0, pfc_req_next;
reg [16+QFB-1:0] lfc_quanta_reg = 0, lfc_quanta_next;
reg [16+QFB-1:0] pfc_quanta_reg[0:7], pfc_quanta_next[0:7];
reg stat_rx_lfc_pkt_reg = 1'b0, stat_rx_lfc_pkt_next;
reg stat_rx_lfc_xon_reg = 1'b0, stat_rx_lfc_xon_next;
reg stat_rx_lfc_xoff_reg = 1'b0, stat_rx_lfc_xoff_next;
reg stat_rx_pfc_pkt_reg = 1'b0, stat_rx_pfc_pkt_next;
reg [7:0] stat_rx_pfc_xon_reg = 0, stat_rx_pfc_xon_next;
reg [7:0] stat_rx_pfc_xoff_reg = 0, stat_rx_pfc_xoff_next;
assign rx_lfc_req = lfc_req_reg;
assign rx_pfc_req = pfc_req_reg;
assign stat_rx_lfc_pkt = stat_rx_lfc_pkt_reg;
assign stat_rx_lfc_xon = stat_rx_lfc_xon_reg;
assign stat_rx_lfc_xoff = stat_rx_lfc_xoff_reg;
assign stat_rx_lfc_paused = lfc_req_reg;
assign stat_rx_pfc_pkt = stat_rx_pfc_pkt_reg;
assign stat_rx_pfc_xon = stat_rx_pfc_xon_reg;
assign stat_rx_pfc_xoff = stat_rx_pfc_xoff_reg;
assign stat_rx_pfc_paused = pfc_req_reg;
integer k;
initial begin
for (k = 0; k < 8; k = k + 1) begin
pfc_quanta_reg[k] = 0;
end
end
always @* begin
stat_rx_lfc_pkt_next = 1'b0;
stat_rx_lfc_xon_next = 1'b0;
stat_rx_lfc_xoff_next = 1'b0;
stat_rx_pfc_pkt_next = 1'b0;
stat_rx_pfc_xon_next = 0;
stat_rx_pfc_xoff_next = 0;
if (cfg_quanta_clk_en && rx_lfc_ack) begin
if (lfc_quanta_reg > cfg_quanta_step) begin
lfc_quanta_next = lfc_quanta_reg - cfg_quanta_step;
end else begin
lfc_quanta_next = 0;
end
end else begin
lfc_quanta_next = lfc_quanta_reg;
end
lfc_req_next = (lfc_quanta_reg != 0) && rx_lfc_en && cfg_rx_lfc_en;
for (k = 0; k < 8; k = k + 1) begin
if (cfg_quanta_clk_en && rx_pfc_ack[k]) begin
if (pfc_quanta_reg[k] > cfg_quanta_step) begin
pfc_quanta_next[k] = pfc_quanta_reg[k] - cfg_quanta_step;
end else begin
pfc_quanta_next[k] = 0;
end
end else begin
pfc_quanta_next[k] = pfc_quanta_reg[k];
end
pfc_req_next[k] = (pfc_quanta_reg[k] != 0) && rx_pfc_en[k] && cfg_rx_pfc_en;
end
if (mcf_valid) begin
if (mcf_opcode == cfg_rx_lfc_opcode && cfg_rx_lfc_en) begin
stat_rx_lfc_pkt_next = 1'b1;
stat_rx_lfc_xon_next = {mcf_params[7:0], mcf_params[15:8]} == 0;
stat_rx_lfc_xoff_next = {mcf_params[7:0], mcf_params[15:8]} != 0;
lfc_quanta_next = {mcf_params[7:0], mcf_params[15:8], {QFB{1'b0}}};
end else if (PFC_ENABLE && mcf_opcode == cfg_rx_pfc_opcode && cfg_rx_pfc_en) begin
stat_rx_pfc_pkt_next = 1'b1;
for (k = 0; k < 8; k = k + 1) begin
if (mcf_params[k+8]) begin
stat_rx_pfc_xon_next[k] = {mcf_params[16+(k*16)+0 +: 8], mcf_params[16+(k*16)+8 +: 8]} == 0;
stat_rx_pfc_xoff_next[k] = {mcf_params[16+(k*16)+0 +: 8], mcf_params[16+(k*16)+8 +: 8]} != 0;
pfc_quanta_next[k] = {mcf_params[16+(k*16)+0 +: 8], mcf_params[16+(k*16)+8 +: 8], {QFB{1'b0}}};
end
end
end
end
end
always @(posedge clk) begin
lfc_req_reg <= lfc_req_next;
pfc_req_reg <= pfc_req_next;
lfc_quanta_reg <= lfc_quanta_next;
for (k = 0; k < 8; k = k + 1) begin
pfc_quanta_reg[k] <= pfc_quanta_next[k];
end
stat_rx_lfc_pkt_reg <= stat_rx_lfc_pkt_next;
stat_rx_lfc_xon_reg <= stat_rx_lfc_xon_next;
stat_rx_lfc_xoff_reg <= stat_rx_lfc_xoff_next;
stat_rx_pfc_pkt_reg <= stat_rx_pfc_pkt_next;
stat_rx_pfc_xon_reg <= stat_rx_pfc_xon_next;
stat_rx_pfc_xoff_reg <= stat_rx_pfc_xoff_next;
if (rst) begin
lfc_req_reg <= 1'b0;
pfc_req_reg <= 8'd0;
lfc_quanta_reg <= 0;
for (k = 0; k < 8; k = k + 1) begin
pfc_quanta_reg[k] <= 0;
end
stat_rx_lfc_pkt_reg <= 1'b0;
stat_rx_lfc_xon_reg <= 1'b0;
stat_rx_lfc_xoff_reg <= 1'b0;
stat_rx_pfc_pkt_reg <= 1'b0;
stat_rx_pfc_xon_reg <= 0;
stat_rx_pfc_xoff_reg <= 0;
end
end
endmodule
`resetall