/*

Copyright (c) 2018 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

`timescale 1ns / 1ps

/*
 * AXI4 DMA
 */
module axi_dma #
(
    // Width of AXI data bus in bits
    parameter AXI_DATA_WIDTH = 32,
    // Width of AXI address bus in bits
    parameter AXI_ADDR_WIDTH = 16,
    // Width of AXI wstrb (width of data bus in words)
    parameter AXI_STRB_WIDTH = (AXI_DATA_WIDTH/8),
    // Width of AXI ID signal
    parameter AXI_ID_WIDTH = 8,
    // Maximum AXI burst length to generate
    parameter AXI_MAX_BURST_LEN = 16,
    // Width of AXI stream interfaces in bits
    parameter AXIS_DATA_WIDTH = AXI_DATA_WIDTH,
    // Use AXI stream tkeep signal
    parameter AXIS_KEEP_ENABLE = (AXIS_DATA_WIDTH>8),
    // AXI stream tkeep signal width (words per cycle)
    parameter AXIS_KEEP_WIDTH = (AXIS_DATA_WIDTH/8),
    // Use AXI stream tlast signal
    parameter AXIS_LAST_ENABLE = 1,
    // Propagate AXI stream tid signal
    parameter AXIS_ID_ENABLE = 0,
    // AXI stream tid signal width
    parameter AXIS_ID_WIDTH = 8,
    // Propagate AXI stream tdest signal
    parameter AXIS_DEST_ENABLE = 0,
    // AXI stream tdest signal width
    parameter AXIS_DEST_WIDTH = 8,
    // Propagate AXI stream tuser signal
    parameter AXIS_USER_ENABLE = 1,
    // AXI stream tuser signal width
    parameter AXIS_USER_WIDTH = 1,
    // Width of length field
    parameter LEN_WIDTH = 20,
    // Width of tag field
    parameter TAG_WIDTH = 8,
    // Enable support for scatter/gather DMA
    // (multiple descriptors per AXI stream frame)
    parameter ENABLE_SG = 0,
    // Enable support for unaligned transfers
    parameter ENABLE_UNALIGNED = 0
)
(
    input  wire                       clk,
    input  wire                       rst,

    /*
     * AXI read descriptor input
     */
    input  wire [AXI_ADDR_WIDTH-1:0]  s_axis_read_desc_addr,
    input  wire [LEN_WIDTH-1:0]       s_axis_read_desc_len,
    input  wire [TAG_WIDTH-1:0]       s_axis_read_desc_tag,
    input  wire [AXIS_ID_WIDTH-1:0]   s_axis_read_desc_id,
    input  wire [AXIS_DEST_WIDTH-1:0] s_axis_read_desc_dest,
    input  wire [AXIS_USER_WIDTH-1:0] s_axis_read_desc_user,
    input  wire                       s_axis_read_desc_valid,
    output wire                       s_axis_read_desc_ready,

    /*
     * AXI read descriptor status output
     */
    output wire [TAG_WIDTH-1:0]       m_axis_read_desc_status_tag,
    output wire                       m_axis_read_desc_status_valid,

    /*
     * AXI stream read data output
     */
    output wire [AXIS_DATA_WIDTH-1:0] m_axis_read_data_tdata,
    output wire [AXIS_KEEP_WIDTH-1:0] m_axis_read_data_tkeep,
    output wire                       m_axis_read_data_tvalid,
    input  wire                       m_axis_read_data_tready,
    output wire                       m_axis_read_data_tlast,
    output wire [AXIS_ID_WIDTH-1:0]   m_axis_read_data_tid,
    output wire [AXIS_DEST_WIDTH-1:0] m_axis_read_data_tdest,
    output wire [AXIS_USER_WIDTH-1:0] m_axis_read_data_tuser,

    /*
     * AXI write descriptor input
     */
    input  wire [AXI_ADDR_WIDTH-1:0]  s_axis_write_desc_addr,
    input  wire [LEN_WIDTH-1:0]       s_axis_write_desc_len,
    input  wire [TAG_WIDTH-1:0]       s_axis_write_desc_tag,
    input  wire                       s_axis_write_desc_valid,
    output wire                       s_axis_write_desc_ready,

    /*
     * AXI write descriptor status output
     */
    output wire [LEN_WIDTH-1:0]       m_axis_write_desc_status_len,
    output wire [TAG_WIDTH-1:0]       m_axis_write_desc_status_tag,
    output wire [AXIS_ID_WIDTH-1:0]   m_axis_write_desc_status_id,
    output wire [AXIS_DEST_WIDTH-1:0] m_axis_write_desc_status_dest,
    output wire [AXIS_USER_WIDTH-1:0] m_axis_write_desc_status_user,
    output wire                       m_axis_write_desc_status_valid,

    /*
     * AXI stream write data input
     */
    input  wire [AXIS_DATA_WIDTH-1:0] s_axis_write_data_tdata,
    input  wire [AXIS_KEEP_WIDTH-1:0] s_axis_write_data_tkeep,
    input  wire                       s_axis_write_data_tvalid,
    output wire                       s_axis_write_data_tready,
    input  wire                       s_axis_write_data_tlast,
    input  wire [AXIS_ID_WIDTH-1:0]   s_axis_write_data_tid,
    input  wire [AXIS_DEST_WIDTH-1:0] s_axis_write_data_tdest,
    input  wire [AXIS_USER_WIDTH-1:0] s_axis_write_data_tuser,

    /*
     * AXI master interface
     */
    output wire [AXI_ID_WIDTH-1:0]    m_axi_awid,
    output wire [AXI_ADDR_WIDTH-1:0]  m_axi_awaddr,
    output wire [7:0]                 m_axi_awlen,
    output wire [2:0]                 m_axi_awsize,
    output wire [1:0]                 m_axi_awburst,
    output wire                       m_axi_awlock,
    output wire [3:0]                 m_axi_awcache,
    output wire [2:0]                 m_axi_awprot,
    output wire                       m_axi_awvalid,
    input  wire                       m_axi_awready,
    output wire [AXI_DATA_WIDTH-1:0]  m_axi_wdata,
    output wire [AXI_STRB_WIDTH-1:0]  m_axi_wstrb,
    output wire                       m_axi_wlast,
    output wire                       m_axi_wvalid,
    input  wire                       m_axi_wready,
    input  wire [AXI_ID_WIDTH-1:0]    m_axi_bid,
    input  wire [1:0]                 m_axi_bresp,
    input  wire                       m_axi_bvalid,
    output wire                       m_axi_bready,
    output wire [AXI_ID_WIDTH-1:0]    m_axi_arid,
    output wire [AXI_ADDR_WIDTH-1:0]  m_axi_araddr,
    output wire [7:0]                 m_axi_arlen,
    output wire [2:0]                 m_axi_arsize,
    output wire [1:0]                 m_axi_arburst,
    output wire                       m_axi_arlock,
    output wire [3:0]                 m_axi_arcache,
    output wire [2:0]                 m_axi_arprot,
    output wire                       m_axi_arvalid,
    input  wire                       m_axi_arready,
    input  wire [AXI_ID_WIDTH-1:0]    m_axi_rid,
    input  wire [AXI_DATA_WIDTH-1:0]  m_axi_rdata,
    input  wire [1:0]                 m_axi_rresp,
    input  wire                       m_axi_rlast,
    input  wire                       m_axi_rvalid,
    output wire                       m_axi_rready,

    /*
     * Configuration
     */
    input  wire                       read_enable,
    input  wire                       write_enable,
    input  wire                       write_abort
);

axi_dma_rd #(
    .AXI_DATA_WIDTH(AXI_DATA_WIDTH),
    .AXI_ADDR_WIDTH(AXI_ADDR_WIDTH),
    .AXI_STRB_WIDTH(AXI_STRB_WIDTH),
    .AXI_ID_WIDTH(AXI_ID_WIDTH),
    .AXI_MAX_BURST_LEN(AXI_MAX_BURST_LEN),
    .AXIS_DATA_WIDTH(AXIS_DATA_WIDTH),
    .AXIS_KEEP_ENABLE(AXIS_KEEP_ENABLE),
    .AXIS_KEEP_WIDTH(AXIS_KEEP_WIDTH),
    .AXIS_LAST_ENABLE(AXIS_LAST_ENABLE),
    .AXIS_ID_ENABLE(AXIS_ID_ENABLE),
    .AXIS_ID_WIDTH(AXIS_ID_WIDTH),
    .AXIS_DEST_ENABLE(AXIS_DEST_ENABLE),
    .AXIS_DEST_WIDTH(AXIS_DEST_WIDTH),
    .AXIS_USER_ENABLE(AXIS_USER_ENABLE),
    .AXIS_USER_WIDTH(AXIS_USER_WIDTH),
    .LEN_WIDTH(LEN_WIDTH),
    .TAG_WIDTH(TAG_WIDTH),
    .ENABLE_SG(ENABLE_SG),
    .ENABLE_UNALIGNED(ENABLE_UNALIGNED)
)
axi_dma_rd_inst (
    .clk(clk),
    .rst(rst),

    /*
     * AXI read descriptor input
     */
    .s_axis_read_desc_addr(s_axis_read_desc_addr),
    .s_axis_read_desc_len(s_axis_read_desc_len),
    .s_axis_read_desc_tag(s_axis_read_desc_tag),
    .s_axis_read_desc_id(s_axis_read_desc_id),
    .s_axis_read_desc_dest(s_axis_read_desc_dest),
    .s_axis_read_desc_user(s_axis_read_desc_user),
    .s_axis_read_desc_valid(s_axis_read_desc_valid),
    .s_axis_read_desc_ready(s_axis_read_desc_ready),

    /*
     * AXI read descriptor status output
     */
    .m_axis_read_desc_status_tag(m_axis_read_desc_status_tag),
    .m_axis_read_desc_status_valid(m_axis_read_desc_status_valid),

    /*
     * AXI stream read data output
     */
    .m_axis_read_data_tdata(m_axis_read_data_tdata),
    .m_axis_read_data_tkeep(m_axis_read_data_tkeep),
    .m_axis_read_data_tvalid(m_axis_read_data_tvalid),
    .m_axis_read_data_tready(m_axis_read_data_tready),
    .m_axis_read_data_tlast(m_axis_read_data_tlast),
    .m_axis_read_data_tid(m_axis_read_data_tid),
    .m_axis_read_data_tdest(m_axis_read_data_tdest),
    .m_axis_read_data_tuser(m_axis_read_data_tuser),

    /*
     * AXI master interface
     */
    .m_axi_arid(m_axi_arid),
    .m_axi_araddr(m_axi_araddr),
    .m_axi_arlen(m_axi_arlen),
    .m_axi_arsize(m_axi_arsize),
    .m_axi_arburst(m_axi_arburst),
    .m_axi_arlock(m_axi_arlock),
    .m_axi_arcache(m_axi_arcache),
    .m_axi_arprot(m_axi_arprot),
    .m_axi_arvalid(m_axi_arvalid),
    .m_axi_arready(m_axi_arready),
    .m_axi_rid(m_axi_rid),
    .m_axi_rdata(m_axi_rdata),
    .m_axi_rresp(m_axi_rresp),
    .m_axi_rlast(m_axi_rlast),
    .m_axi_rvalid(m_axi_rvalid),
    .m_axi_rready(m_axi_rready),

    /*
     * Configuration
     */
    .enable(read_enable)
);

axi_dma_wr #(
    .AXI_DATA_WIDTH(AXI_DATA_WIDTH),
    .AXI_ADDR_WIDTH(AXI_ADDR_WIDTH),
    .AXI_STRB_WIDTH(AXI_STRB_WIDTH),
    .AXI_ID_WIDTH(AXI_ID_WIDTH),
    .AXI_MAX_BURST_LEN(AXI_MAX_BURST_LEN),
    .AXIS_DATA_WIDTH(AXIS_DATA_WIDTH),
    .AXIS_KEEP_ENABLE(AXIS_KEEP_ENABLE),
    .AXIS_KEEP_WIDTH(AXIS_KEEP_WIDTH),
    .AXIS_LAST_ENABLE(AXIS_LAST_ENABLE),
    .AXIS_ID_ENABLE(AXIS_ID_ENABLE),
    .AXIS_ID_WIDTH(AXIS_ID_WIDTH),
    .AXIS_DEST_ENABLE(AXIS_DEST_ENABLE),
    .AXIS_DEST_WIDTH(AXIS_DEST_WIDTH),
    .AXIS_USER_ENABLE(AXIS_USER_ENABLE),
    .AXIS_USER_WIDTH(AXIS_USER_WIDTH),
    .LEN_WIDTH(LEN_WIDTH),
    .TAG_WIDTH(TAG_WIDTH),
    .ENABLE_SG(ENABLE_SG),
    .ENABLE_UNALIGNED(ENABLE_UNALIGNED)
)
axi_dma_wr_inst (
    .clk(clk),
    .rst(rst),

    /*
     * AXI write descriptor input
     */
    .s_axis_write_desc_addr(s_axis_write_desc_addr),
    .s_axis_write_desc_len(s_axis_write_desc_len),
    .s_axis_write_desc_tag(s_axis_write_desc_tag),
    .s_axis_write_desc_valid(s_axis_write_desc_valid),
    .s_axis_write_desc_ready(s_axis_write_desc_ready),

    /*
     * AXI write descriptor status output
     */
    .m_axis_write_desc_status_len(m_axis_write_desc_status_len),
    .m_axis_write_desc_status_tag(m_axis_write_desc_status_tag),
    .m_axis_write_desc_status_id(m_axis_write_desc_status_id),
    .m_axis_write_desc_status_dest(m_axis_write_desc_status_dest),
    .m_axis_write_desc_status_user(m_axis_write_desc_status_user),
    .m_axis_write_desc_status_valid(m_axis_write_desc_status_valid),

    /*
     * AXI stream write data input
     */
    .s_axis_write_data_tdata(s_axis_write_data_tdata),
    .s_axis_write_data_tkeep(s_axis_write_data_tkeep),
    .s_axis_write_data_tvalid(s_axis_write_data_tvalid),
    .s_axis_write_data_tready(s_axis_write_data_tready),
    .s_axis_write_data_tlast(s_axis_write_data_tlast),
    .s_axis_write_data_tid(s_axis_write_data_tid),
    .s_axis_write_data_tdest(s_axis_write_data_tdest),
    .s_axis_write_data_tuser(s_axis_write_data_tuser),

    /*
     * AXI master interface
     */
    .m_axi_awid(m_axi_awid),
    .m_axi_awaddr(m_axi_awaddr),
    .m_axi_awlen(m_axi_awlen),
    .m_axi_awsize(m_axi_awsize),
    .m_axi_awburst(m_axi_awburst),
    .m_axi_awlock(m_axi_awlock),
    .m_axi_awcache(m_axi_awcache),
    .m_axi_awprot(m_axi_awprot),
    .m_axi_awvalid(m_axi_awvalid),
    .m_axi_awready(m_axi_awready),
    .m_axi_wdata(m_axi_wdata),
    .m_axi_wstrb(m_axi_wstrb),
    .m_axi_wlast(m_axi_wlast),
    .m_axi_wvalid(m_axi_wvalid),
    .m_axi_wready(m_axi_wready),
    .m_axi_bid(m_axi_bid),
    .m_axi_bresp(m_axi_bresp),
    .m_axi_bvalid(m_axi_bvalid),
    .m_axi_bready(m_axi_bready),

    /*
     * Configuration
     */
    .enable(write_enable),
    .abort(write_abort)
);

endmodule