OpenFPGA/openfpga_flow/benchmarks/iwls2005/mem_ctrl/rtl/mc_dp.v

245 lines
7.8 KiB
Verilog

/////////////////////////////////////////////////////////////////////
//// ////
//// WISHBONE Memory Controller ////
//// Data Path Module ////
//// ////
//// ////
//// Author: Rudolf Usselmann ////
//// rudi@asics.ws ////
//// ////
//// ////
//// Downloaded from: http://www.opencores.org/cores/mem_ctrl/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000-2002 Rudolf Usselmann ////
//// www.asics.ws ////
//// rudi@asics.ws ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer.////
//// ////
//// THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY ////
//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ////
//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS ////
//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR ////
//// OR CONTRIBUTORS 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. ////
//// ////
/////////////////////////////////////////////////////////////////////
// CVS Log
//
// $Id: mc_dp.v,v 1.6 2002/01/21 13:08:52 rudi Exp $
//
// $Date: 2002/01/21 13:08:52 $
// $Revision: 1.6 $
// $Author: rudi $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: mc_dp.v,v $
// Revision 1.6 2002/01/21 13:08:52 rudi
//
// Fixed several minor bugs, cleaned up the code further ...
//
// Revision 1.5 2001/12/11 02:47:19 rudi
//
// - Made some changes not to expect clock during reset ...
//
// Revision 1.4 2001/11/29 02:16:28 rudi
//
//
// - More Synthesis cleanup, mostly for speed
// - Several bug fixes
// - Changed code to avoid auto-precharge and
// burst-terminate combinations (apparently illegal ?)
// Now we will do a manual precharge ...
//
// Revision 1.3 2001/09/24 00:38:21 rudi
//
// Changed Reset to be active high and async.
//
// Revision 1.2 2001/08/10 08:16:21 rudi
//
// - Changed IO names to be more clear.
// - Uniquifyed define names to be core specific.
// - Removed "Refresh Early" configuration
//
// Revision 1.1 2001/07/29 07:34:41 rudi
//
//
// 1) Changed Directory Structure
// 2) Fixed several minor bugs
//
// Revision 1.2 2001/06/03 11:37:17 rudi
//
//
// 1) Fixed Chip Select Mask Register
// - Power On Value is now all ones
// - Comparison Logic is now correct
//
// 2) All resets are now asynchronous
//
// 3) Converted Power On Delay to an configurable item
//
// 4) Added reset to Chip Select Output Registers
//
// 5) Forcing all outputs to Hi-Z state during reset
//
// Revision 1.1.1.1 2001/05/13 09:39:47 rudi
// Created Directory Structure
//
//
//
//
`include "mc_defines.v"
module mc_dp( clk, rst, csc,
wb_cyc_i, wb_stb_i, wb_ack_o, mem_ack, wb_data_i, wb_data_o,
wb_read_go, wb_we_i,
mc_clk, mc_data_del, mc_dp_i, mc_data_o, mc_dp_o,
dv, pack_le0, pack_le1, pack_le2,
byte_en, par_err
);
input clk, rst;
input [31:0] csc;
input wb_cyc_i;
input wb_stb_i;
input mem_ack;
input wb_ack_o;
input [31:0] wb_data_i;
output [31:0] wb_data_o;
input wb_read_go;
input wb_we_i;
input mc_clk;
input [35:0] mc_data_del;
input [3:0] mc_dp_i;
output [31:0] mc_data_o;
output [3:0] mc_dp_o;
input dv;
input pack_le0, pack_le1, pack_le2; // Pack Latch Enable
input [3:0] byte_en; // High Active byte enables
output par_err;
////////////////////////////////////////////////////////////////////
//
// Local Registers & Wires
//
reg [31:0] wb_data_o;
reg [31:0] mc_data_o;
wire [35:0] rd_fifo_out;
wire rd_fifo_clr;
reg [3:0] mc_dp_o;
reg par_err_r;
reg [7:0] byte0, byte1, byte2;
reg [31:0] mc_data_d;
wire [2:0] mem_type;
wire [1:0] bus_width;
wire pen;
wire re;
// Aliases
assign mem_type = csc[3:1];
assign bus_width = csc[5:4];
assign pen = csc[11];
////////////////////////////////////////////////////////////////////
//
// WB READ Data Path
//
always @(mem_type or rd_fifo_out or mc_data_d)
if( (mem_type == `MC_MEM_TYPE_SDRAM) |
(mem_type == `MC_MEM_TYPE_SRAM) ) wb_data_o = rd_fifo_out[31:0];
else wb_data_o = mc_data_d;
//assign rd_fifo_clr = !(rst | !wb_cyc_i | (wb_we_i & wb_stb_i) );
assign rd_fifo_clr = !wb_cyc_i | (wb_we_i & wb_stb_i);
assign re = wb_ack_o & wb_read_go;
mc_rd_fifo u0(
.clk( clk ),
.rst( rst ),
.clr( rd_fifo_clr ),
.din( mc_data_del ),
.we( dv ),
.dout( rd_fifo_out ),
.re( re )
);
////////////////////////////////////////////////////////////////////
//
// WB WRITE Data Path
//
always @(posedge clk)
if(wb_ack_o | (mem_type != `MC_MEM_TYPE_SDRAM) )
mc_data_o <= #1 wb_data_i;
////////////////////////////////////////////////////////////////////
//
// Read Data Packing
//
always @(posedge clk)
if(pack_le0) byte0 <= #1 mc_data_del[7:0];
always @(posedge clk)
if(pack_le1 & (bus_width == `MC_BW_8)) byte1 <= #1 mc_data_del[7:0];
else
if(pack_le0 & (bus_width == `MC_BW_16)) byte1 <= #1 mc_data_del[15:8];
always @(posedge clk)
if(pack_le2) byte2 <= #1 mc_data_del[7:0];
always @(bus_width or mc_data_del or byte0 or byte1 or byte2)
if(bus_width == `MC_BW_8) mc_data_d = {mc_data_del[7:0], byte2, byte1, byte0};
else
if(bus_width == `MC_BW_16) mc_data_d = {mc_data_del[15:0], byte1, byte0};
else mc_data_d = mc_data_del[31:0];
////////////////////////////////////////////////////////////////////
//
// Parity Generation
//
always @(posedge clk)
if(wb_ack_o | (mem_type != `MC_MEM_TYPE_SDRAM) )
mc_dp_o <= #1 { ^wb_data_i[31:24], ^wb_data_i[23:16],
^wb_data_i[15:08], ^wb_data_i[07:00] };
////////////////////////////////////////////////////////////////////
//
// Parity Checking
//
assign par_err = !wb_we_i & mem_ack & pen & (
(( ^rd_fifo_out[31:24] ^ rd_fifo_out[35] ) & byte_en[3] ) |
(( ^rd_fifo_out[23:16] ^ rd_fifo_out[34] ) & byte_en[2] ) |
(( ^rd_fifo_out[15:08] ^ rd_fifo_out[33] ) & byte_en[1] ) |
(( ^rd_fifo_out[07:00] ^ rd_fifo_out[32] ) & byte_en[0] )
);
endmodule