// *************************************************************************** // *************************************************************************** // 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 responsabilities 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: // // // 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_dacfifo_dac #( parameter AXI_DATA_WIDTH = 512, parameter AXI_LENGTH = 15, parameter DAC_DATA_WIDTH = 64, parameter DAC_MEM_ADDRESS_WIDTH = 8) ( input axi_clk, input axi_dvalid, input [(AXI_DATA_WIDTH-1):0] axi_ddata, output reg axi_dready, input axi_dlast, input axi_xfer_req, input [ 3:0] dma_last_beats, input dac_clk, input dac_rst, input dac_valid, output [(DAC_DATA_WIDTH-1):0] dac_data, output dac_xfer_out, output reg dac_dunf); localparam MEM_RATIO = AXI_DATA_WIDTH/DAC_DATA_WIDTH; localparam AXI_ADDRESS_WIDTH = (MEM_RATIO == 1) ? DAC_MEM_ADDRESS_WIDTH : (MEM_RATIO == 2) ? (DAC_MEM_ADDRESS_WIDTH - 1) : (MEM_RATIO == 4) ? (DAC_MEM_ADDRESS_WIDTH - 2) : (DAC_MEM_ADDRESS_WIDTH - 3); localparam AXI_BUF_THRESHOLD_LO = 3 * (AXI_LENGTH+1); localparam AXI_BUF_THRESHOLD_HI = {(AXI_ADDRESS_WIDTH){1'b1}} - (AXI_LENGTH+1); localparam DAC_BUF_THRESHOLD_LO = 3 * (AXI_LENGTH+1) * MEM_RATIO; localparam DAC_BUF_THRESHOLD_HI = {(DAC_MEM_ADDRESS_WIDTH){1'b1}} - (AXI_LENGTH+1) * MEM_RATIO; localparam DAC_ARINCR = (AXI_LENGTH+1) * MEM_RATIO; // internal registers reg [(AXI_ADDRESS_WIDTH-1):0] axi_mem_waddr = 'd0; reg [(AXI_ADDRESS_WIDTH-1):0] axi_mem_laddr = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_waddr_g = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_laddr_g = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_raddr = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_raddr_m1 = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_raddr_m2 = 'd0; reg [(AXI_ADDRESS_WIDTH-1):0] axi_mem_addr_diff = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_raddr = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_raddr_g = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_waddr = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_waddr_m1 = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_waddr_m2 = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_laddr = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_laddr_m1 = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_laddr_m2 = 'd0; reg [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_addr_diff = 'd0; reg dac_mem_init = 1'b0; reg dac_mem_init_d = 1'b0; reg dac_mem_enable = 1'b0; reg [ 2:0] dac_xfer_req_m = 3'b0; reg dac_xfer_init = 1'b0; reg [ 3:0] dac_last_beats = 4'b0; reg [ 3:0] dac_last_beats_m = 4'b0; reg [ 3:0] dac_beat_cnt = 4'b0; reg dac_dlast = 1'b0; reg dac_dlast_m1 = 1'b0; reg dac_dlast_m2 = 1'b0; reg dac_dlast_inmem = 1'b0; reg dac_mem_valid = 1'b0; // internal signals wire [AXI_ADDRESS_WIDTH:0] axi_mem_addr_diff_s; wire [(AXI_ADDRESS_WIDTH-1):0] axi_mem_raddr_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_waddr_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_laddr_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_waddr_b2g_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_laddr_b2g_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] axi_mem_raddr_m2_g2b_s; wire [DAC_MEM_ADDRESS_WIDTH:0] dac_mem_addr_diff_s; wire dac_xfer_init_s; wire dac_last_axi_beats_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_raddr_b2g_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_waddr_m2_g2b_s; wire [(DAC_MEM_ADDRESS_WIDTH-1):0] dac_mem_laddr_m2_g2b_s; // write interface always @(posedge axi_clk) begin if (axi_xfer_req == 1'b0) begin axi_mem_waddr <= 'd0; axi_mem_waddr_g <= 'd0; axi_mem_laddr <= {AXI_ADDRESS_WIDTH{1'b1}}; end else begin if (axi_dvalid == 1'b1) begin axi_mem_waddr <= axi_mem_waddr + 1'b1; axi_mem_laddr <= (axi_dlast == 1'b1) ? axi_mem_waddr : axi_mem_laddr; end axi_mem_waddr_g <= axi_mem_waddr_b2g_s; axi_mem_laddr_g <= axi_mem_laddr_b2g_s; end end ad_b2g # ( .DATA_WIDTH(DAC_MEM_ADDRESS_WIDTH) ) i_axi_mem_waddr_b2g ( .din (axi_mem_waddr_s), .dout (axi_mem_waddr_b2g_s)); ad_b2g # ( .DATA_WIDTH(DAC_MEM_ADDRESS_WIDTH) ) i_axi_mem_laddr_b2g ( .din (axi_mem_laddr_s), .dout (axi_mem_laddr_b2g_s)); // scale the axi_mem_* addresses assign axi_mem_raddr_s = (MEM_RATIO == 1) ? axi_mem_raddr : (MEM_RATIO == 2) ? axi_mem_raddr[(DAC_MEM_ADDRESS_WIDTH-1):1] : (MEM_RATIO == 4) ? axi_mem_raddr[(DAC_MEM_ADDRESS_WIDTH-1):2] : axi_mem_raddr[(DAC_MEM_ADDRESS_WIDTH-1):3]; assign axi_mem_waddr_s = (MEM_RATIO == 1) ? axi_mem_waddr : (MEM_RATIO == 2) ? {axi_mem_waddr, 1'b0} : (MEM_RATIO == 4) ? {axi_mem_waddr, 2'b0} : {axi_mem_waddr, 3'b0}; assign axi_mem_laddr_s = (MEM_RATIO == 1) ? axi_mem_laddr : (MEM_RATIO == 2) ? {axi_mem_laddr, 1'b0} : (MEM_RATIO == 4) ? {axi_mem_laddr, 2'b0} : {axi_mem_laddr, 3'b0}; // incomming data flow control assign axi_mem_addr_diff_s = {1'b1, axi_mem_waddr} - axi_mem_raddr_s; always @(posedge axi_clk) begin if (axi_xfer_req == 1'b0) begin axi_mem_addr_diff <= 'd0; axi_mem_raddr <= 'd0; axi_mem_raddr_m1 <= 'd0; axi_mem_raddr_m2 <= 'd0; axi_dready <= 'd0; end else begin axi_mem_raddr_m1 <= dac_mem_raddr_g; axi_mem_raddr_m2 <= axi_mem_raddr_m1; axi_mem_raddr <= axi_mem_raddr_m2_g2b_s; axi_mem_addr_diff <= axi_mem_addr_diff_s[AXI_ADDRESS_WIDTH-1:0]; if (axi_mem_addr_diff >= AXI_BUF_THRESHOLD_HI) begin axi_dready <= 1'b0; end else begin axi_dready <= 1'b1; end end end ad_g2b #( .DATA_WIDTH(DAC_MEM_ADDRESS_WIDTH) ) i_axi_mem_raddr_m2_g2b ( .din (axi_mem_raddr_m2), .dout (axi_mem_raddr_m2_g2b_s)); // CDC for xfer_req signal always @(posedge dac_clk) begin if (dac_rst == 1'b1) begin dac_xfer_req_m <= 3'b0; end else begin dac_xfer_req_m <= {dac_xfer_req_m[1:0], axi_xfer_req}; end end assign dac_xfer_out = dac_xfer_req_m[2]; assign dac_xfer_init_s = ~dac_xfer_req_m[2] & dac_xfer_req_m[1]; // read interface always @(posedge dac_clk) begin if (dac_xfer_out == 1'b0) begin dac_mem_init <= 1'b0; dac_mem_init_d <= 1'b0; dac_mem_enable <= 1'b0; end else begin if (dac_xfer_init == 1'b1) begin dac_mem_init <= 1'b1; end if ((dac_mem_init == 1'b1) && (dac_mem_addr_diff > DAC_BUF_THRESHOLD_LO)) begin dac_mem_init <= 1'b0; end dac_mem_init_d <= dac_mem_init; // memory is ready when the initial fill up is done dac_mem_enable <= (dac_mem_init_d & ~dac_mem_init) ? 1'b1 : dac_mem_enable; end dac_xfer_init <= dac_xfer_init_s; end always @(posedge dac_clk) begin if (dac_xfer_out == 1'b0) begin dac_mem_waddr <= 'b0; dac_mem_waddr_m1 <= 'b0; dac_mem_waddr_m2 <= 'b0; dac_mem_laddr <= 'b0; dac_mem_laddr_m1 <= 'b0; dac_mem_laddr_m2 <= 'b0; dac_dlast <= 1'b0; dac_dlast_m1 <= 1'b0; dac_dlast_m2 <= 1'b0; end else begin dac_mem_waddr_m1 <= axi_mem_waddr_g; dac_mem_waddr_m2 <= dac_mem_waddr_m1; dac_mem_waddr <= dac_mem_waddr_m2_g2b_s; dac_mem_laddr_m1 <= axi_mem_laddr_g; dac_mem_laddr_m2 <= dac_mem_laddr_m1; dac_mem_laddr <= dac_mem_laddr_m2_g2b_s; dac_dlast_m1 <= axi_dlast; dac_dlast_m2 <= dac_dlast_m1; dac_dlast <= dac_dlast_m2; end end ad_g2b #( .DATA_WIDTH(DAC_MEM_ADDRESS_WIDTH) ) i_dac_mem_waddr_m2_g2b ( .din (dac_mem_waddr_m2), .dout (dac_mem_waddr_m2_g2b_s)); ad_g2b #( .DATA_WIDTH(DAC_MEM_ADDRESS_WIDTH) ) i_dac_mem_laddr_m2_g2b ( .din (dac_mem_laddr_m2), .dout (dac_mem_laddr_m2_g2b_s)); assign dac_mem_addr_diff_s = {1'b1, dac_mem_waddr} - dac_mem_raddr; always @(posedge dac_clk) begin dac_mem_valid <= (dac_mem_enable) ? dac_valid : 1'b0; end // CDC for the dma_last_beats always @(posedge dac_clk) begin if (dac_rst == 1'b1) begin dac_last_beats <= 4'b0; dac_last_beats_m <= 4'b0; end else begin dac_last_beats_m <= dma_last_beats; dac_last_beats <= dac_last_beats_m; end end // If the MEM_RATIO is grater than one, it can happen that not all the DAC beats from // an AXI beat are valid. In this case the invalid data is dropped. // The axi_dlast indicates the last AXI beat. The valid number of DAC beats on the last AXI beat // commes from the AXI write module. (axi_dacfifo_wr.v) assign dac_last_axi_beats_s = ((dac_dlast_inmem == 1'b1) && (dac_mem_raddr >= dac_mem_laddr) && (dac_mem_raddr < dac_mem_laddr + MEM_RATIO)) ? 1'b1 : 1'b0; always @(posedge dac_clk) begin if (dac_xfer_out == 1'b0) begin dac_mem_raddr <= 'd0; dac_beat_cnt <= 'd0; dac_dlast_inmem <= 1'b0; end else begin if (dac_dlast == 1'b1) begin dac_dlast_inmem <= 1'b1; end else if (dac_mem_raddr == dac_mem_laddr + MEM_RATIO) begin dac_dlast_inmem <= 1'b0; end if (dac_mem_valid == 1'b1) begin dac_beat_cnt <= ((dac_beat_cnt >= MEM_RATIO-1) || ((dac_last_beats > 4'b1) && (dac_last_axi_beats_s > 1'b0) && (dac_beat_cnt == dac_last_beats-1))) ? 0 : dac_beat_cnt + 1; dac_mem_raddr <= ((dac_last_axi_beats_s) && (dac_beat_cnt == dac_last_beats-1)) ? (dac_mem_laddr + MEM_RATIO) : dac_mem_raddr + 1'b1; end dac_mem_raddr_g <= dac_mem_raddr_b2g_s; end end ad_b2g # ( .DATA_WIDTH(DAC_MEM_ADDRESS_WIDTH) ) i_dac_mem_raddr_b2g ( .din (dac_mem_raddr), .dout (dac_mem_raddr_b2g_s)); // underflow generation, there is no overflow always @(posedge dac_clk) begin if(dac_xfer_out == 1'b0) begin dac_mem_addr_diff <= 'b0; dac_dunf <= 1'b0; end else begin dac_mem_addr_diff <= dac_mem_addr_diff_s[DAC_MEM_ADDRESS_WIDTH-1:0]; dac_dunf <= (dac_mem_addr_diff == 1'b0) ? 1'b1 : 1'b0; end end // instantiations ad_mem_asym #( .A_ADDRESS_WIDTH (AXI_ADDRESS_WIDTH), .A_DATA_WIDTH (AXI_DATA_WIDTH), .B_ADDRESS_WIDTH (DAC_MEM_ADDRESS_WIDTH), .B_DATA_WIDTH (DAC_DATA_WIDTH)) i_mem_asym ( .clka (axi_clk), .wea (axi_dvalid), .addra (axi_mem_waddr), .dina (axi_ddata), .clkb (dac_clk), .addrb (dac_mem_raddr), .doutb (dac_data)); endmodule // *************************************************************************** // ***************************************************************************