pluto_hdl_adi/library/xilinx/axi_adcfifo/axi_adcfifo_wr.v

419 lines
13 KiB
Verilog

// ***************************************************************************
// ***************************************************************************
// Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
//
// In this HDL repository, there are many different and unique modules, consisting
// of various HDL (Verilog or VHDL) components. The individual modules are
// developed independently, and may be accompanied by separate and unique license
// terms.
//
// The user should read each of these license terms, and understand the
// freedoms and responsibilities that he or she has by using this source/core.
//
// This core is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
// A PARTICULAR PURPOSE.
//
// Redistribution and use of source or resulting binaries, with or without modification
// of this file, are permitted under one of the following two license terms:
//
// 1. The GNU General Public License version 2 as published by the
// Free Software Foundation, which can be found in the top level directory
// of this repository (LICENSE_GPL2), and also online at:
// <https://www.gnu.org/licenses/old-licenses/gpl-2.0.html>
//
// OR
//
// 2. An ADI specific BSD license, which can be found in the top level directory
// of this repository (LICENSE_ADIBSD), and also on-line at:
// https://github.com/analogdevicesinc/hdl/blob/master/LICENSE_ADIBSD
// This will allow to generate bit files and not release the source code,
// as long as it attaches to an ADI device.
//
// ***************************************************************************
// ***************************************************************************
`timescale 1ns/100ps
module axi_adcfifo_wr #(
parameter AXI_DATA_WIDTH = 512,
parameter AXI_SIZE = 2,
parameter AXI_LENGTH = 16,
parameter AXI_ADDRESS = 32'h00000000,
parameter AXI_ADDRESS_LIMIT = 32'h00000000) (
// request and synchronization
input dma_xfer_req,
// read interface
output reg axi_rd_req,
output reg [ 31:0] axi_rd_addr,
// fifo interface
input adc_rst,
input adc_clk,
input adc_wr,
input [AXI_DATA_WIDTH-1:0] adc_wdata,
// axi interface
input axi_clk,
input axi_resetn,
output reg axi_awvalid,
output [ 3:0] axi_awid,
output [ 1:0] axi_awburst,
output axi_awlock,
output [ 3:0] axi_awcache,
output [ 2:0] axi_awprot,
output [ 3:0] axi_awqos,
output [ 3:0] axi_awuser,
output [ 7:0] axi_awlen,
output [ 2:0] axi_awsize,
output reg [ 31:0] axi_awaddr,
input axi_awready,
output axi_wvalid,
output [AXI_DATA_WIDTH-1:0] axi_wdata,
output [AXI_BYTE_WIDTH-1:0] axi_wstrb,
output axi_wlast,
output [ 3:0] axi_wuser,
input axi_wready,
input axi_bvalid,
input [ 3:0] axi_bid,
input [ 1:0] axi_bresp,
input [ 3:0] axi_buser,
output axi_bready,
// axi status
output reg axi_dwovf,
output reg axi_dwunf,
output reg axi_werror);
localparam AXI_BYTE_WIDTH = AXI_DATA_WIDTH/8;
localparam AXI_AWINCR = AXI_LENGTH * AXI_BYTE_WIDTH;
localparam BUF_THRESHOLD_LO = 8'd6;
localparam BUF_THRESHOLD_HI = 8'd250;
// internal registers
reg [ 2:0] adc_xfer_req_m = 'd0;
reg adc_xfer_init = 'd0;
reg adc_xfer_limit = 'd0;
reg adc_xfer_enable = 'd0;
reg [ 31:0] adc_xfer_addr = 'd0;
reg [ 7:0] adc_waddr = 'd0;
reg [ 7:0] adc_waddr_g = 'd0;
reg adc_rel_enable = 'd0;
reg adc_rel_toggle = 'd0;
reg [ 7:0] adc_rel_waddr = 'd0;
reg [ 2:0] axi_rel_toggle_m = 'd0;
reg [ 7:0] axi_rel_waddr = 'd0;
reg [ 7:0] axi_waddr_m1 = 'd0;
reg [ 7:0] axi_waddr_m2 = 'd0;
reg [ 7:0] axi_waddr = 'd0;
reg [ 7:0] axi_addr_diff = 'd0;
reg axi_almost_full = 'd0;
reg axi_almost_empty = 'd0;
reg [ 2:0] axi_xfer_req_m = 'd0;
reg axi_xfer_init = 'd0;
reg [ 7:0] axi_raddr = 'd0;
reg axi_rd = 'd0;
reg axi_rlast = 'd0;
reg axi_rd_d = 'd0;
reg axi_rlast_d = 'd0;
reg [AXI_DATA_WIDTH-1:0] axi_rdata_d = 'd0;
reg axi_reset = 'd0;
// internal signals
wire axi_rel_toggle_s;
wire [ 8:0] axi_addr_diff_s;
wire axi_wready_s;
wire axi_rd_s;
wire axi_req_s;
wire axi_rlast_s;
wire [AXI_DATA_WIDTH-1:0] axi_rdata_s;
// binary to grey conversion
function [7:0] b2g;
input [7:0] b;
reg [7:0] g;
begin
g[7] = b[7];
g[6] = b[7] ^ b[6];
g[5] = b[6] ^ b[5];
g[4] = b[5] ^ b[4];
g[3] = b[4] ^ b[3];
g[2] = b[3] ^ b[2];
g[1] = b[2] ^ b[1];
g[0] = b[1] ^ b[0];
b2g = g;
end
endfunction
// grey to binary conversion
function [7:0] g2b;
input [7:0] g;
reg [7:0] b;
begin
b[7] = g[7];
b[6] = b[7] ^ g[6];
b[5] = b[6] ^ g[5];
b[4] = b[5] ^ g[4];
b[3] = b[4] ^ g[3];
b[2] = b[3] ^ g[2];
b[1] = b[2] ^ g[1];
b[0] = b[1] ^ g[0];
g2b = b;
end
endfunction
// fifo interface
always @(posedge adc_clk) begin
if (adc_rst == 1'b1) begin
adc_waddr <= 'd0;
adc_waddr_g <= 'd0;
adc_xfer_req_m <= 'd0;
adc_xfer_init <= 'd0;
adc_xfer_limit <= 'd0;
adc_xfer_enable <= 'd0;
adc_xfer_addr <= 'd0;
adc_rel_enable <= 'd0;
adc_rel_toggle <= 'd0;
adc_rel_waddr <= 'd0;
end else begin
if ((adc_wr == 1'b1) && (adc_xfer_enable == 1'b1)) begin
adc_waddr <= adc_waddr + 1'b1;
end
adc_waddr_g <= b2g(adc_waddr);
adc_xfer_req_m <= {adc_xfer_req_m[1:0], dma_xfer_req};
adc_xfer_init <= adc_xfer_req_m[1] & ~adc_xfer_req_m[2];
if (adc_xfer_init == 1'b1) begin
adc_xfer_limit <= 1'd1;
end else if ((adc_xfer_addr >= AXI_ADDRESS_LIMIT) || (adc_xfer_enable == 1'b0)) begin
adc_xfer_limit <= 1'd0;
end
if (adc_xfer_init == 1'b1) begin
adc_xfer_enable <= 1'b1;
adc_xfer_addr <= AXI_ADDRESS;
end else if ((adc_waddr[1:0] == 2'h3) && (adc_wr == 1'b1)) begin
adc_xfer_enable <= adc_xfer_req_m[2] & adc_xfer_limit;
adc_xfer_addr <= adc_xfer_addr + AXI_AWINCR;
end
if (adc_waddr[1:0] == 2'h3) begin
adc_rel_enable <= adc_wr;
end else begin
adc_rel_enable <= 1'd0;
end
if (adc_rel_enable == 1'b1) begin
adc_rel_toggle <= ~adc_rel_toggle;
adc_rel_waddr <= adc_waddr;
end
end
end
// fifo signals on axi side
assign axi_rel_toggle_s = axi_rel_toggle_m[2] ^ axi_rel_toggle_m[1];
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_rel_toggle_m <= 'd0;
axi_rel_waddr <= 'd0;
axi_waddr_m1 <= 'd0;
axi_waddr_m2 <= 'd0;
axi_waddr <= 'd0;
end else begin
axi_rel_toggle_m <= {axi_rel_toggle_m[1:0], adc_rel_toggle};
if (axi_rel_toggle_s == 1'b1) begin
axi_rel_waddr <= adc_rel_waddr;
end
axi_waddr_m1 <= adc_waddr_g;
axi_waddr_m2 <= axi_waddr_m1;
axi_waddr <= g2b(axi_waddr_m2);
end
end
// overflow (no underflow possible)
assign axi_addr_diff_s = {1'b1, axi_waddr} - axi_raddr;
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_addr_diff <= 'd0;
axi_almost_full <= 'd0;
axi_dwunf <= 'd0;
axi_almost_empty <= 'd0;
axi_dwovf <= 'd0;
end else begin
axi_addr_diff <= axi_addr_diff_s[7:0];
if (axi_addr_diff > BUF_THRESHOLD_HI) begin
axi_almost_full <= 1'b1;
axi_dwunf <= axi_almost_empty;
end else begin
axi_almost_full <= 1'b0;
axi_dwunf <= 1'b0;
end
if (axi_addr_diff < BUF_THRESHOLD_LO) begin
axi_almost_empty <= 1'b1;
axi_dwovf <= axi_almost_full;
end else begin
axi_almost_empty <= 1'b0;
axi_dwovf <= 1'b0;
end
end
end
// transfer request is required to keep things in sync
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_xfer_req_m <= 'd0;
axi_xfer_init <= 'd0;
end else begin
axi_xfer_req_m <= {axi_xfer_req_m[1:0], dma_xfer_req};
axi_xfer_init <= axi_xfer_req_m[1] & ~axi_xfer_req_m[2];
end
end
// read is initiated if xfer enabled
assign axi_wready_s = ~axi_wvalid | axi_wready;
assign axi_rd_s = (axi_rel_waddr == axi_raddr) ? 1'b0 : axi_wready_s;
assign axi_req_s = (axi_raddr[1:0] == 2'h0) ? axi_rd_s : 1'b0;
assign axi_rlast_s = (axi_raddr[1:0] == 2'h3) ? axi_rd_s : 1'b0;
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_raddr <= 'd0;
axi_rd <= 'd0;
axi_rlast <= 'd0;
axi_rd_d <= 'd0;
axi_rlast_d <= 'd0;
axi_rdata_d <= 'd0;
end else begin
if (axi_rd_s == 1'b1) begin
axi_raddr <= axi_raddr + 1'b1;
end
axi_rd <= axi_rd_s;
axi_rlast <= axi_rlast_s;
axi_rd_d <= axi_rd;
axi_rlast_d <= axi_rlast;
axi_rdata_d <= axi_rdata_s;
end
end
// send read request for every burst about to be completed
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_rd_req <= 'd0;
axi_rd_addr <= 'd0;
end else begin
axi_rd_req <= axi_rlast_s;
if (axi_xfer_init == 1'b1) begin
axi_rd_addr <= AXI_ADDRESS;
end else if (axi_rd_req == 1'b1) begin
axi_rd_addr <= axi_rd_addr + AXI_AWINCR;
end
end
end
// address channel
assign axi_awid = 4'b0000;
assign axi_awburst = 2'b01;
assign axi_awlock = 1'b0;
assign axi_awcache = 4'b0010;
assign axi_awprot = 3'b000;
assign axi_awqos = 4'b0000;
assign axi_awuser = 4'b0001;
assign axi_awlen = AXI_LENGTH - 1;
assign axi_awsize = AXI_SIZE;
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_awvalid <= 'd0;
axi_awaddr <= 'd0;
end else begin
if (axi_awvalid == 1'b1) begin
if (axi_awready == 1'b1) begin
axi_awvalid <= 1'b0;
end
end else begin
if (axi_req_s == 1'b1) begin
axi_awvalid <= 1'b1;
end
end
if (axi_xfer_init == 1'b1) begin
axi_awaddr <= AXI_ADDRESS;
end else if ((axi_awvalid == 1'b1) && (axi_awready == 1'b1)) begin
axi_awaddr <= axi_awaddr + AXI_AWINCR;
end
end
end
// write channel
assign axi_wstrb = {AXI_BYTE_WIDTH{1'b1}};
assign axi_wuser = 4'b0000;
// response channel
assign axi_bready = 1'b1;
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_werror <= 'd0;
end else begin
axi_werror <= axi_bvalid & axi_bready & axi_bresp[1];
end
end
// fifo needs a reset
always @(posedge axi_clk or negedge axi_resetn) begin
if (axi_resetn == 1'b0) begin
axi_reset <= 1'b1;
end else begin
axi_reset <= 1'b0;
end
end
// interface handler
ad_axis_inf_rx #(.DATA_WIDTH(AXI_DATA_WIDTH)) i_axis_inf (
.clk (axi_clk),
.rst (axi_reset),
.valid (axi_rd_d),
.last (axi_rlast_d),
.data (axi_rdata_d),
.inf_valid (axi_wvalid),
.inf_last (axi_wlast),
.inf_data (axi_wdata),
.inf_ready (axi_wready));
// buffer
ad_mem #(.DATA_WIDTH(AXI_DATA_WIDTH), .ADDRESS_WIDTH(8)) i_mem (
.clka (adc_clk),
.wea (adc_wr),
.addra (adc_waddr),
.dina (adc_wdata),
.clkb (axi_clk),
.reb (1'b1),
.addrb (axi_raddr),
.doutb (axi_rdata_s));
endmodule
// ***************************************************************************
// ***************************************************************************