1
0
mirror of https://github.com/KastnerRG/riffa.git synced 2024-12-24 22:58:54 +08:00
riffa/fpga/riffa_hdl/fifo_packer_64.v
2016-02-09 15:23:37 -08:00

127 lines
4.9 KiB
Verilog

// ----------------------------------------------------------------------
// Copyright (c) 2016, The Regents of the University of California 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 The Regents of the University of California
// nor the names of its contributors may be used to endorse or
// promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL REGENTS OF THE
// UNIVERSITY OF CALIFORNIA BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, 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.
// ----------------------------------------------------------------------
//----------------------------------------------------------------------------
// Filename: fifo_packer_64.v
// Version: 1.00.a
// Verilog Standard: Verilog-2001
// Description: Packs 32 or 64 bit received data into a 64 bit wide FIFO.
// Assumes the FIFO always has room to accommodate the data.
// Author: Matt Jacobsen
// History: @mattj: Version 2.0
// Additional Comments:
//-----------------------------------------------------------------------------
`timescale 1ns/1ns
module fifo_packer_64 (
input CLK,
input RST,
input [63:0] DATA_IN, // Incoming data
input [1:0] DATA_IN_EN, // Incoming data enable
input DATA_IN_DONE, // Incoming data packet end
input DATA_IN_ERR, // Incoming data error
input DATA_IN_FLUSH, // End of incoming data
output [63:0] PACKED_DATA, // Outgoing data
output PACKED_WEN, // Outgoing data write enable
output PACKED_DATA_DONE, // End of outgoing data packet
output PACKED_DATA_ERR, // Error in outgoing data
output PACKED_DATA_FLUSHED // End of outgoing data
);
reg [1:0] rPackedCount=0, _rPackedCount=0;
reg rPackedDone=0, _rPackedDone=0;
reg rPackedErr=0, _rPackedErr=0;
reg rPackedFlush=0, _rPackedFlush=0;
reg rPackedFlushed=0, _rPackedFlushed=0;
reg [95:0] rPackedData=96'd0, _rPackedData=96'd0;
reg [63:0] rDataIn=64'd0, _rDataIn=64'd0;
reg [1:0] rDataInEn=0, _rDataInEn=0;
reg [63:0] rDataMasked=64'd0, _rDataMasked=64'd0;
reg [1:0] rDataMaskedEn=0, _rDataMaskedEn=0;
assign PACKED_DATA = rPackedData[63:0];
assign PACKED_WEN = rPackedCount[1];
assign PACKED_DATA_DONE = rPackedDone;
assign PACKED_DATA_ERR = rPackedErr;
assign PACKED_DATA_FLUSHED = rPackedFlushed;
// Buffers input data until 2 words are available, then writes 2 words out.
wire [63:0] wMask = {64{1'b1}}<<(32*rDataInEn);
wire [63:0] wDataMasked = ~wMask & rDataIn;
always @ (posedge CLK) begin
rPackedCount <= #1 (RST ? 2'd0 : _rPackedCount);
rPackedDone <= #1 (RST ? 1'd0 : _rPackedDone);
rPackedErr <= #1 (RST ? 1'd0 : _rPackedErr);
rPackedFlush <= #1 (RST ? 1'd0 : _rPackedFlush);
rPackedFlushed <= #1 (RST ? 1'd0 : _rPackedFlushed);
rPackedData <= #1 (RST ? 96'd0 : _rPackedData);
rDataIn <= #1 _rDataIn;
rDataInEn <= #1 (RST ? 2'd0 : _rDataInEn);
rDataMasked <= #1 _rDataMasked;
rDataMaskedEn <= #1 (RST ? 2'd0 : _rDataMaskedEn);
end
always @ (*) begin
// Buffer and mask the input data.
_rDataIn = DATA_IN;
_rDataInEn = DATA_IN_EN;
_rDataMasked = wDataMasked;
_rDataMaskedEn = rDataInEn;
// Count what's in our buffer. When we reach 2 words, 2 words will be written
// out. If flush is requested, write out whatever remains.
if (rPackedFlush && rPackedCount[0])
_rPackedCount = 2;
else
_rPackedCount = rPackedCount + rDataMaskedEn - {rPackedCount[1], 1'd0};
// Shift data into and out of our buffer as we receive and write out data.
if (rDataMaskedEn != 2'd0)
_rPackedData = ((rPackedData>>(32*{rPackedCount[1], 1'd0})) | (rDataMasked<<(32*rPackedCount[0])));
else
_rPackedData = (rPackedData>>(32*{rPackedCount[1], 1'd0}));
// Track done/error/flush signals.
_rPackedDone = DATA_IN_DONE;
_rPackedErr = DATA_IN_ERR;
_rPackedFlush = DATA_IN_FLUSH;
_rPackedFlushed = rPackedFlush;
end
endmodule