avalon-dma/design/dma_verilog/wb_dma_wb_slv.v
2018-03-06 15:11:37 +01:00

177 lines
5.8 KiB
Verilog

/////////////////////////////////////////////////////////////////////
//// ////
//// WISHBONE DMA WISHBONE Slave Interface ////
//// ////
//// ////
//// Author: Rudolf Usselmann ////
//// rudi@asics.ws ////
//// ////
//// ////
//// Downloaded from: http://www.opencores.org/cores/wb_dma/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// 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: wb_dma_wb_slv.v,v 1.4 2002-02-01 01:54:45 rudi Exp $
//
// $Date: 2002-02-01 01:54:45 $
// $Revision: 1.4 $
// $Author: rudi $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: not supported by cvs2svn $
// Revision 1.3 2001/10/19 04:35:04 rudi
//
// - Made the core parameterized
//
// Revision 1.2 2001/08/15 05:40:30 rudi
//
// - Changed IO names to be more clear.
// - Uniquifyed define names to be core specific.
// - Added Section 3.10, describing DMA restart.
//
// Revision 1.1 2001/07/29 08:57:02 rudi
//
//
// 1) Changed Directory Structure
// 2) Added restart signal (REST)
//
// Revision 1.2 2001/06/05 10:22:37 rudi
//
//
// - Added Support of up to 31 channels
// - Added support for 2,4 and 8 priority levels
// - Now can have up to 31 channels
// - Added many configuration items
// - Changed reset to async
//
// Revision 1.1.1.1 2001/03/19 13:10:59 rudi
// Initial Release
//
//
//
`include "wb_dma_defines.v"
module wb_dma_wb_slv(clk, rst,
wb_data_i, wb_data_o, wb_addr_i, wb_sel_i, wb_we_i, wb_cyc_i,
wb_stb_i, wb_ack_o, wb_err_o, wb_rty_o,
// This is the register File Interface
slv_adr, slv_din, slv_dout, slv_re, slv_we,
// Pass through Interface
pt_sel, slv_pt_out, slv_pt_in
);
parameter rf_addr = 0;
input clk, rst;
// --------------------------------------
// WISHBONE INTERFACE
input [31:0] wb_data_i;
output [31:0] wb_data_o;
input [31:0] wb_addr_i;
input [3:0] wb_sel_i;
input wb_we_i;
input wb_cyc_i;
input wb_stb_i;
output wb_ack_o;
output wb_err_o;
output wb_rty_o;
// This is the register File Interface
output [31:0] slv_adr; // Slave Address
input [31:0] slv_din; // Slave Input Data
output [31:0] slv_dout; // Slave Output Data
output slv_re; // Slave Read Enable
output slv_we; // Slave Write Enable
// Pass through Interface
output pt_sel; // Pass Through Mode Active
output [70:0] slv_pt_out; // Grouped WISHBONE out signals
input [34:0] slv_pt_in; // Grouped WISHBONE in signals
////////////////////////////////////////////////////////////////////
//
// Local Wires
//
reg slv_re, slv_we;
wire rf_sel;
reg rf_ack;
reg [31:0] slv_adr, slv_dout;
////////////////////////////////////////////////////////////////////
//
// Misc Logic
//
assign rf_sel = `WDMA_REG_SEL ;
////////////////////////////////////////////////////////////////////
//
// Pass Through Logic
//
//assign pt_sel = !rf_sel;
assign pt_sel = !rf_sel & wb_cyc_i;
assign slv_pt_out = {wb_data_i, wb_addr_i, wb_sel_i, wb_we_i, wb_cyc_i, wb_stb_i};
assign {wb_data_o, wb_ack_o, wb_err_o, wb_rty_o} = pt_sel ? slv_pt_in :
{slv_din, rf_ack, 1'b0, 1'b0};
////////////////////////////////////////////////////////////////////
//
// Register File Logic
//
always @(posedge clk)
slv_adr <= #1 wb_addr_i;
always @(posedge clk)
slv_re <= #1 rf_sel & wb_cyc_i & wb_stb_i & !wb_we_i & !rf_ack & !slv_re;
always @(posedge clk)
slv_we <= #1 rf_sel & wb_cyc_i & wb_stb_i & wb_we_i & !rf_ack;
always @(posedge clk)
slv_dout <= #1 wb_data_i;
always @(posedge clk)
rf_ack <= #1 (slv_re | slv_we) & wb_cyc_i & wb_stb_i & !rf_ack ;
endmodule