Subversion Repositories wb_dma

/////////////////////////////////////////////////////////////////////
////                                                             ////
////  WISHBONE DMA Priority Encoder Sub-Module                   ////
////                                                             ////
////                                                             ////
////  Author: Rudolf Usselmann                                   ////
////          rudi@asics.ws                                      ////
////                                                             ////
////                                                             ////
////  Downloaded from: http://www.opencores.org/cores/wb_dma/    ////
////                                                             ////
/////////////////////////////////////////////////////////////////////
////                                                             ////
//// Copyright (C) 2001 Rudolf Usselmann                         ////
////                    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_pri_enc_sub.v,v 1.1 2001-08-07 08:00:43 rudi Exp $
//
//  $Date: 2001-08-07 08:00:43 $
//  $Revision: 1.1 $
//  $Author: rudi $
//  $Locker:  $
//  $State: Exp $
//
// Change History:
//               $Log: not supported by cvs2svn $
//
//
//
//
//
 
`include "wb_dma_defines.v"
 
// Priority Encoder
//
// Determines the channel with the highest priority, also takes
// the valid bit in consideration
 
module wb_dma_pri_enc_sub(valid, pri_in, pri_out);
input		valid;
input	[2:0]	pri_in;
output	[7:0]	pri_out;
 
reg	[7:0]	pri_out;
 
`ifdef PRI_8
always @(valid or pri_in)
	if(!valid)		pri_out = 8'b0000_0001;
	else
	if(pri_in==3'h0)	pri_out = 8'b0000_0001;
	else
	if(pri_in==3'h1)	pri_out = 8'b0000_0010;
	else
	if(pri_in==3'h2)	pri_out = 8'b0000_0100;
	else
	if(pri_in==3'h3)	pri_out = 8'b0000_1000;
	else
	if(pri_in==3'h4)	pri_out = 8'b0001_0000;
	else
	if(pri_in==3'h5)	pri_out = 8'b0010_0000;
	else
	if(pri_in==3'h6)	pri_out = 8'b0100_0000;
	else			pri_out = 8'b1000_0000;
`else
`ifdef PRI_4
always @(valid or pri_in)
	if(!valid)		pri_out = 8'b0000_0001;
	else
	if(pri_in==3'h0)	pri_out = 8'b0000_0001;
	else
	if(pri_in==3'h1)	pri_out = 8'b0000_0010;
	else
	if(pri_in==3'h2)	pri_out = 8'b0000_0100;
	else			pri_out = 8'b0000_1000;
`else
always @(valid or pri_in)
	if(!valid)		pri_out = 8'b0000_0001;
	else
	if(pri_in==3'h0)	pri_out = 8'b0000_0001;
	else			pri_out = 8'b0000_0010;
`endif
`endif
 
endmodule