pluto_hdl_adi/library/util_axis_fifo/util_axis_fifo.v

214 lines
5.9 KiB
Verilog

// ***************************************************************************
// ***************************************************************************
// Copyright 2013(c) Analog Devices, Inc.
// Author: Lars-Peter Clausen <lars@metafoo.de>
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
// - Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// - Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in
// the documentation and/or other materials provided with the
// distribution.
// - Neither the name of Analog Devices, Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
// - The use of this software may or may not infringe the patent rights
// of one or more patent holders. This license does not release you
// from the requirement that you obtain separate licenses from these
// patent holders to use this software.
// - Use of the software either in source or binary form, must be run
// on or directly connected to an Analog Devices Inc. component.
//
// THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED.
//
// IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, INTELLECTUAL PROPERTY
// RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// ***************************************************************************
// ***************************************************************************
module util_axis_fifo (
input m_axis_aclk,
input m_axis_aresetn,
input m_axis_ready,
output m_axis_valid,
output [DATA_WIDTH-1:0] m_axis_data,
output [ADDRESS_WIDTH:0] m_axis_level,
input s_axis_aclk,
input s_axis_aresetn,
output s_axis_ready,
input s_axis_valid,
input [DATA_WIDTH-1:0] s_axis_data,
output s_axis_empty,
output [ADDRESS_WIDTH:0] s_axis_room
);
parameter DATA_WIDTH = 64;
parameter ASYNC_CLK = 1;
parameter ADDRESS_WIDTH = 4;
parameter S_AXIS_REGISTERED = 1;
generate if (ADDRESS_WIDTH == 0) begin
reg [DATA_WIDTH-1:0] cdc_sync_fifo_ram;
reg s_axis_waddr = 1'b0;
reg m_axis_raddr = 1'b0;
wire m_axis_waddr;
wire s_axis_raddr;
sync_bits #(
.NUM_OF_BITS(1),
.ASYNC_CLK(ASYNC_CLK)
) i_waddr_sync (
.out_clk(m_axis_aclk),
.out_resetn(m_axis_aresetn),
.in(s_axis_waddr),
.out(m_axis_waddr)
);
sync_bits #(
.NUM_OF_BITS(1),
.ASYNC_CLK(ASYNC_CLK)
) i_raddr_sync (
.out_clk(s_axis_aclk),
.out_resetn(s_axis_aresetn),
.in(m_axis_raddr),
.out(s_axis_raddr)
);
assign m_axis_valid = m_axis_raddr != m_axis_waddr;
assign m_axis_level = m_axis_valid;
assign s_axis_ready = s_axis_raddr == s_axis_waddr;
assign s_axis_empty = s_axis_ready;
assign s_axis_room = s_axis_ready;
always @(posedge s_axis_aclk) begin
if (s_axis_ready)
cdc_sync_fifo_ram <= s_axis_data;
end
always @(posedge s_axis_aclk) begin
if (s_axis_aresetn == 1'b0) begin
s_axis_waddr <= 1'b0;
end else begin
if (s_axis_ready & s_axis_valid) begin
s_axis_waddr <= s_axis_waddr + 1'b1;
end
end
end
always @(posedge m_axis_aclk) begin
if (m_axis_aresetn == 1'b0) begin
m_axis_raddr <= 1'b0;
end else begin
if (m_axis_valid & m_axis_ready)
m_axis_raddr <= m_axis_raddr + 1'b1;
end
end
assign m_axis_data = cdc_sync_fifo_ram;
end else begin
reg [DATA_WIDTH-1:0] ram[0:2**ADDRESS_WIDTH-1];
wire [ADDRESS_WIDTH-1:0] s_axis_waddr;
wire [ADDRESS_WIDTH-1:0] m_axis_raddr;
wire _m_axis_ready;
wire _m_axis_valid;
if (ASYNC_CLK == 1) begin
fifo_address_gray_pipelined #(
.ADDRESS_WIDTH(ADDRESS_WIDTH)
) i_address_gray (
.m_axis_aclk(m_axis_aclk),
.m_axis_aresetn(m_axis_aresetn),
.m_axis_ready(_m_axis_ready),
.m_axis_valid(_m_axis_valid),
.m_axis_raddr(m_axis_raddr),
.m_axis_level(m_axis_level),
.s_axis_aclk(s_axis_aclk),
.s_axis_aresetn(s_axis_aresetn),
.s_axis_ready(s_axis_ready),
.s_axis_valid(s_axis_valid),
.s_axis_empty(s_axis_empty),
.s_axis_waddr(s_axis_waddr),
.s_axis_room(s_axis_room)
);
end else begin
fifo_address_sync #(
.ADDRESS_WIDTH(ADDRESS_WIDTH)
) i_address_sync (
.clk(m_axis_aclk),
.resetn(m_axis_aresetn),
.m_axis_ready(_m_axis_ready),
.m_axis_valid(_m_axis_valid),
.m_axis_raddr(m_axis_raddr),
.m_axis_level(m_axis_level),
.s_axis_ready(s_axis_ready),
.s_axis_valid(s_axis_valid),
.s_axis_empty(s_axis_empty),
.s_axis_waddr(s_axis_waddr),
.s_axis_room(s_axis_room)
);
end
always @(posedge s_axis_aclk) begin
if (s_axis_ready)
ram[s_axis_waddr] <= s_axis_data;
end
if (S_AXIS_REGISTERED == 1) begin
reg [DATA_WIDTH-1:0] data;
reg valid;
always @(posedge m_axis_aclk) begin
if (m_axis_aresetn == 1'b0) begin
valid <= 1'b0;
end else begin
if (_m_axis_valid)
valid <= 1'b1;
else if (m_axis_ready)
valid <= 1'b0;
end
end
always @(posedge m_axis_aclk) begin
if (~valid || m_axis_ready)
data <= ram[m_axis_raddr];
end
assign _m_axis_ready = ~valid || m_axis_ready;
assign m_axis_data = data;
assign m_axis_valid = valid;
end else begin
assign _m_axis_ready = m_axis_ready;
assign m_axis_valid = _m_axis_valid;
assign m_axis_data = ram[m_axis_raddr];
end
end endgenerate
endmodule