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// OpenSPARC T2 Processor File: niu_txc_drr_context.v
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/*********************************************************************
* Orignal Author(s): Rahoul Puri
* Copyright (c) 2004 Sun Microsystems, Inc.
* This verilog model is the confidential and proprietary property of
* Sun Microsystems, Inc., and the possession or use of this model
* requires a written license from Sun Microsystems, Inc.
**********************************************************************/
module niu_txc_drr_context (
ClrMaxBurst, // Clear max burst bit in control register
NewMaxBurst, // Max burst bit in control register
PacketByteCount, // Byte count of the packet that was serviced
// Data Fetch State Machine
input [15:0] PacketByteCount;
// DRR Arbiter State Machine
input AddCreditToContext;
input ClrDeficitForEofList;
input [4:0] NextDMAChannel;
input [4:0] ContextNumber;
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
// Parameters and Defines
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
assign NoDeficit = (byteCount < {1'b0, contextBurst});
assign addCredit = (AddCreditToContext & ContextActiveList);
assign updateMaxBurst = (ClrMaxBurst & NewMaxBurst);
assign updatebyteCount = (PacketDone
(NextDMAChannel == ContextNumber)
/*--------------------------------------------------------------*/
/*--------------------------------------------------------------*/
if (!Reset_L) contextBurst <= #`SD 20'h0;
else if (updateMaxBurst) contextBurst <= #`SD MaxBurst;
if (!Reset_L) byteCount <= #`SD 21'h0;
else if (FlushEngine) byteCount <= #`SD 21'h0;
else if (DMA_Reset_Done) byteCount <= #`SD 21'h0;
else if (ClrDeficitForEofList & DMA_EofList) byteCount <= #`SD 21'h0;
if (NoDeficit) byteCount <= #`SD 21'h0;
else byteCount <= #`SD (byteCount - {1'b0, contextBurst});
else if (updatebyteCount) byteCount <= #`SD (byteCount
{5'h0, PacketByteCount});