pluto_hdl_adi/library/util_rfifo/util_rfifo.v

147 lines
4.9 KiB
Coq
Raw Normal View History

// ***************************************************************************
// ***************************************************************************
// Copyright 2011(c) Analog Devices, Inc.
//
// 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.
// ***************************************************************************
// ***************************************************************************
// ***************************************************************************
// ***************************************************************************
`timescale 1ns/100ps
module util_rfifo (
rstn,
clk,
m_rd,
m_rdata,
m_runf,
s_rd,
s_rdata,
s_runf,
fifo_rst,
fifo_wr,
fifo_wdata,
fifo_wfull,
fifo_rd,
fifo_rdata,
fifo_rempty,
fifo_runf);
// parameters (S) bus width must be greater than (M)
parameter M_DATA_WIDTH = 32;
parameter S_DATA_WIDTH = 64;
parameter READ_SELECT = 1;
// common clock
input rstn;
input clk;
// master/slave write
input m_rd;
output [M_DATA_WIDTH-1:0] m_rdata;
output m_runf;
output s_rd;
input [S_DATA_WIDTH-1:0] s_rdata;
input s_runf;
// fifo interface
output fifo_rst;
output fifo_wr;
output [S_DATA_WIDTH-1:0] fifo_wdata;
input fifo_wfull;
output fifo_rd;
input [M_DATA_WIDTH-1:0] fifo_rdata;
input fifo_rempty;
input fifo_runf;
// internal registers
reg fifo_rst = 'd0;
reg [READ_SELECT-1:0] s_rd_cnt = 'd0;
reg m_runf = 'd0;
// defaults
always @(posedge clk or negedge rstn) begin
if (rstn == 1'b0) begin
fifo_rst <= 1'b1;
end else begin
fifo_rst <= 1'b0;
end
end
// write depends on bus width change
assign s_rd = s_rd_cnt[READ_SELECT-1];
assign fifo_wr = s_rd_cnt[READ_SELECT-1];
genvar s;
generate
for (s = 0; s < S_DATA_WIDTH; s = s + 1) begin: g_wdata
assign fifo_wdata[s] = s_rdata[(S_DATA_WIDTH-1)-s];
end
endgenerate
always @(posedge clk) begin
if (m_rd == 1'b1) begin
s_rd_cnt <= s_rd_cnt + 1'b1;
end
end
// read is non-destructive
assign fifo_rd = m_rd;
always @(posedge clk) begin
m_runf <= s_runf | fifo_wfull | fifo_runf | fifo_rempty;
end
genvar m;
generate
for (m = 0; m < M_DATA_WIDTH; m = m + 1) begin: g_rdata
assign m_rdata[m] = fifo_rdata[(M_DATA_WIDTH-1)-m];
end
endgenerate
endmodule
// ***************************************************************************
// ***************************************************************************