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////////////////////////////////////////////////////////////////////// //// //// //// eth_wishbone.v //// //// //// //// This file is part of the Ethernet IP core project //// //// http://www.opencores.org/projects/ethmac/ //// //// //// //// Author(s): //// //// - Igor Mohor (igorM@opencores.org) //// //// //// //// All additional information is available in the Readme.txt //// //// file. //// //// //// ////////////////////////////////////////////////////////////////////// //// //// //// Copyright (C) 2001, 2002 Authors //// //// //// //// 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 source file is free software; you can redistribute it //// //// and/or modify it under the terms of the GNU Lesser General //// //// Public License as published by the Free Software Foundation; //// //// either version 2.1 of the License, or (at your option) any //// //// later version. //// //// //// //// This source is distributed in the hope that it will be //// //// useful, but WITHOUT ANY WARRANTY; without even the implied //// //// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR //// //// PURPOSE. See the GNU Lesser General Public License for more //// //// details. //// //// //// //// You should have received a copy of the GNU Lesser General //// //// Public License along with this source; if not, download it //// //// from http://www.opencores.org/lgpl.shtml //// //// //// ////////////////////////////////////////////////////////////////////// // // CVS Revision History // // $Log: not supported by cvs2svn $ // Revision 1.38 2002/10/10 16:29:30 mohor // BIST added. // // Revision 1.37 2002/09/11 14:18:46 mohor // Sometimes both RxB_IRQ and RxE_IRQ were activated. Bug fixed. // // Revision 1.36 2002/09/10 13:48:46 mohor // Reception is possible after RxPointer is read and not after BD is read. For // that reason RxBDReady is changed to RxReady. // Busy_IRQ interrupt connected. When there is no RxBD ready and frame // comes, interrupt is generated. // // Revision 1.35 2002/09/10 10:35:23 mohor // Ethernet debug registers removed. // // Revision 1.34 2002/09/08 16:31:49 mohor // Async reset for WB_ACK_O removed (when core was in reset, it was // impossible to access BDs). // RxPointers and TxPointers names changed to be more descriptive. // TxUnderRun synchronized. // // Revision 1.33 2002/09/04 18:47:57 mohor // Debug registers reg1, 2, 3, 4 connected. Synchronization of many signals // changed (bugs fixed). Access to un-alligned buffers fixed. RxAbort signal // was not used OK. // // Revision 1.32 2002/08/14 19:31:48 mohor // Register TX_BD_NUM is changed so it contains value of the Tx buffer descriptors. No // need to multiply or devide any more. // // Revision 1.31 2002/07/25 18:29:01 mohor // WriteRxDataToMemory signal changed so end of frame (when last word is // written to fifo) is changed. // // Revision 1.30 2002/07/23 15:28:31 mohor // Ram , used for BDs changed from generic_spram to eth_spram_256x32. // // Revision 1.29 2002/07/20 00:41:32 mohor // ShiftEnded synchronization changed. // // Revision 1.28 2002/07/18 16:11:46 mohor // RxBDAddress takes `ETH_TX_BD_NUM_DEF value after reset. // // Revision 1.27 2002/07/11 02:53:20 mohor // RxPointer bug fixed. // // Revision 1.26 2002/07/10 13:12:38 mohor // Previous bug wasn't succesfully removed. Now fixed. // // Revision 1.25 2002/07/09 23:53:24 mohor // Master state machine had a bug when switching from master write to // master read. // // Revision 1.24 2002/07/09 20:44:41 mohor // m_wb_cyc_o signal released after every single transfer. // // Revision 1.23 2002/05/03 10:15:50 mohor // Outputs registered. Reset changed for eth_wishbone module. // // Revision 1.22 2002/04/24 08:52:19 mohor // Compiler directives added. Tx and Rx fifo size incremented. A "late collision" // bug fixed. // // Revision 1.21 2002/03/29 16:18:11 lampret // Small typo fixed. // // Revision 1.20 2002/03/25 16:19:12 mohor // Any address can be used for Tx and Rx BD pointers. Address does not need // to be aligned. // // Revision 1.19 2002/03/19 12:51:50 mohor // Comments in Slovene language removed. // // Revision 1.18 2002/03/19 12:46:52 mohor // casex changed with case, fifo reset changed. // // Revision 1.17 2002/03/09 16:08:45 mohor // rx_fifo was not always cleared ok. Fixed. // // Revision 1.16 2002/03/09 13:51:20 mohor // Status was not latched correctly sometimes. Fixed. // // Revision 1.15 2002/03/08 06:56:46 mohor // Big Endian problem when sending frames fixed. // // Revision 1.14 2002/03/02 19:12:40 mohor // Byte ordering changed (Big Endian used). casex changed with case because // Xilinx Foundation had problems. Tested in HW. It WORKS. // // Revision 1.13 2002/02/26 16:59:55 mohor // Small fixes for external/internal DMA missmatches. // // Revision 1.12 2002/02/26 16:22:07 mohor // Interrupts changed // // Revision 1.11 2002/02/15 17:07:39 mohor // Status was not written correctly when frames were discarted because of // address mismatch. // // Revision 1.10 2002/02/15 12:17:39 mohor // RxStartFrm cleared when abort or retry comes. // // Revision 1.9 2002/02/15 11:59:10 mohor // Changes that were lost when updating from 1.5 to 1.8 fixed. // // Revision 1.8 2002/02/14 20:54:33 billditt // Addition of new module eth_addrcheck.v // // Revision 1.7 2002/02/12 17:03:47 mohor // RxOverRun added to statuses. // // Revision 1.6 2002/02/11 09:18:22 mohor // Tx status is written back to the BD. // // Revision 1.5 2002/02/08 16:21:54 mohor // Rx status is written back to the BD. // // Revision 1.4 2002/02/06 14:10:21 mohor // non-DMA host interface added. Select the right configutation in eth_defines. // // Revision 1.3 2002/02/05 16:44:39 mohor // Both rx and tx part are finished. Tested with wb_clk_i between 10 and 200 // MHz. Statuses, overrun, control frame transmission and reception still need // to be fixed. // // Revision 1.2 2002/02/01 12:46:51 mohor // Tx part finished. TxStatus needs to be fixed. Pause request needs to be // added. // // Revision 1.1 2002/01/23 10:47:59 mohor // Initial version. Equals to eth_wishbonedma.v at this moment. // // // `include "eth_defines.v" `include "timescale.v" module eth_wishbone ( // WISHBONE common WB_CLK_I, WB_DAT_I, WB_DAT_O, // WISHBONE slave WB_ADR_I, WB_WE_I, WB_ACK_O, BDCs, Reset, // WISHBONE master m_wb_adr_o, m_wb_sel_o, m_wb_we_o, m_wb_dat_o, m_wb_dat_i, m_wb_cyc_o, m_wb_stb_o, m_wb_ack_i, m_wb_err_i, `ifdef ETH_WISHBONE_B3 m_wb_cti_o, m_wb_bte_o, `endif //TX MTxClk, TxStartFrm, TxEndFrm, TxUsedData, TxData, TxRetry, TxAbort, TxUnderRun, TxDone, PerPacketCrcEn, PerPacketPad, //RX MRxClk, RxData, RxValid, RxStartFrm, RxEndFrm, RxAbort, // Register r_TxEn, r_RxEn, r_TxBDNum, TX_BD_NUM_Wr, // Interrupts TxB_IRQ, TxE_IRQ, RxB_IRQ, RxE_IRQ, Busy_IRQ, // Rx Status InvalidSymbol, LatchedCrcError, RxLateCollision, ShortFrame, DribbleNibble, ReceivedPacketTooBig, RxLength, LoadRxStatus, ReceivedPacketGood, // Tx Status RetryCntLatched, RetryLimit, LateCollLatched, DeferLatched, CarrierSenseLost // Bist `ifdef ETH_BIST , trst, SO, SI, shift_DR, capture_DR, extest, tck `endif ); parameter Tp = 1; // WISHBONE common input WB_CLK_I; // WISHBONE clock input [31:0] WB_DAT_I; // WISHBONE data input output [31:0] WB_DAT_O; // WISHBONE data output // WISHBONE slave input [9:2] WB_ADR_I; // WISHBONE address input input WB_WE_I; // WISHBONE write enable input input BDCs; // Buffer descriptors are selected output WB_ACK_O; // WISHBONE acknowledge output // WISHBONE master output [31:0] m_wb_adr_o; // output [3:0] m_wb_sel_o; // output m_wb_we_o; // output [31:0] m_wb_dat_o; // output m_wb_cyc_o; // output m_wb_stb_o; // input [31:0] m_wb_dat_i; // input m_wb_ack_i; // input m_wb_err_i; // `ifdef ETH_WISHBONE_B3 output [2:0] m_wb_cti_o; // Cycle Type Identifier output [1:0] m_wb_bte_o; // Burst Type Extension reg [2:0] m_wb_cti_o; // Cycle Type Identifier `endif input Reset; // Reset signal // Rx Status signals input InvalidSymbol; // Invalid symbol was received during reception in 100 Mbps mode input LatchedCrcError; // CRC error input RxLateCollision; // Late collision occured while receiving frame input ShortFrame; // Frame shorter then the minimum size (r_MinFL) was received while small packets are enabled (r_RecSmall) input DribbleNibble; // Extra nibble received input ReceivedPacketTooBig;// Received packet is bigger than r_MaxFL input [15:0] RxLength; // Length of the incoming frame input LoadRxStatus; // Rx status was loaded input ReceivedPacketGood;// Received packet's length and CRC are good // Tx Status signals input [3:0] RetryCntLatched; // Latched Retry Counter input RetryLimit; // Retry limit reached (Retry Max value + 1 attempts were made) input LateCollLatched; // Late collision occured input DeferLatched; // Defer indication (Frame was defered before sucessfully sent) input CarrierSenseLost; // Carrier Sense was lost during the frame transmission // Tx input MTxClk; // Transmit clock (from PHY) input TxUsedData; // Transmit packet used data input TxRetry; // Transmit packet retry input TxAbort; // Transmit packet abort input TxDone; // Transmission ended output TxStartFrm; // Transmit packet start frame output TxEndFrm; // Transmit packet end frame output [7:0] TxData; // Transmit packet data byte output TxUnderRun; // Transmit packet under-run output PerPacketCrcEn; // Per packet crc enable output PerPacketPad; // Per packet pading // Rx input MRxClk; // Receive clock (from PHY) input [7:0] RxData; // Received data byte (from PHY) input RxValid; // input RxStartFrm; // input RxEndFrm; // input RxAbort; // This signal is set when address doesn't match. //Register input r_TxEn; // Transmit enable input r_RxEn; // Receive enable input [7:0] r_TxBDNum; // Receive buffer descriptor number input TX_BD_NUM_Wr; // RxBDNumber written // Interrupts output TxB_IRQ; output TxE_IRQ; output RxB_IRQ; output RxE_IRQ; output Busy_IRQ; // Bist `ifdef ETH_BIST input trst; input shift_DR, capture_DR, tck, extest; input SI; output SO; `endif reg TxB_IRQ; reg TxE_IRQ; reg RxB_IRQ; reg RxE_IRQ; reg TxStartFrm; reg TxEndFrm; reg [7:0] TxData; reg TxUnderRun; reg TxUnderRun_wb; reg TxBDRead; wire TxStatusWrite; reg [1:0] TxValidBytesLatched; reg [15:0] TxLength; reg [15:0] LatchedTxLength; reg [14:11] TxStatus; reg [14:13] RxStatus; reg TxStartFrm_wb; reg TxRetry_wb; reg TxAbort_wb; reg TxDone_wb; reg TxDone_wb_q; reg TxAbort_wb_q; reg TxRetry_wb_q; reg TxRetryPacket; reg TxDonePulse_q; reg TxAbortPacket; reg RxBDReady; reg RxReady; reg TxBDReady; reg RxBDRead; wire RxStatusWrite; reg [31:0] TxDataLatched; reg [1:0] TxByteCnt; reg LastWord; reg ReadTxDataFromFifo_tck; reg BlockingTxStatusWrite; reg BlockingTxBDRead; reg Flop; reg [7:0] TxBDAddress; reg [7:0] RxBDAddress; reg TxRetrySync1; reg TxAbortSync1; reg TxDoneSync1; reg TxAbort_q; reg TxRetry_q; reg TxUsedData_q; reg [31:0] RxDataLatched2; reg [31:8] RxDataLatched1; // Big Endian Byte Ordering reg [1:0] RxValidBytes; reg [1:0] RxByteCnt; reg LastByteIn; reg ShiftWillEnd; reg WriteRxDataToFifo; reg [15:0] LatchedRxLength; reg RxAbortLatched; reg ShiftEnded; reg RxOverrun; reg BDWrite; // BD Write Enable for access from WISHBONE side reg BDRead; // BD Read access from WISHBONE side wire [31:0] RxBDDataIn; // Rx BD data in wire [31:0] TxBDDataIn; // Tx BD data in reg TxEndFrm_wb; wire TxRetryPulse; wire TxDonePulse; wire TxAbortPulse; wire StartRxBDRead; wire StartTxBDRead; wire TxIRQEn; wire WrapTxStatusBit; wire RxIRQEn; wire WrapRxStatusBit; wire [1:0] TxValidBytes; wire [7:0] TempTxBDAddress; wire [7:0] TempRxBDAddress; wire SetGotData; wire GotDataEvaluate; reg WB_ACK_O; wire [6:0] RxStatusIn; reg [6:0] RxStatusInLatched; reg WbEn, WbEn_q; reg RxEn, RxEn_q; reg TxEn, TxEn_q; wire ram_ce; wire ram_we; wire ram_oe; reg [7:0] ram_addr; reg [31:0] ram_di; wire [31:0] ram_do; wire StartTxPointerRead; reg TxPointerRead; reg TxEn_needed; reg RxEn_needed; wire StartRxPointerRead; reg RxPointerRead; `ifdef ETH_WISHBONE_B3 assign m_wb_bte_o = 2'b00; // Linear burst `endif always @ (posedge WB_CLK_I) begin WB_ACK_O <=#Tp BDWrite & WbEn & WbEn_q | BDRead & WbEn & ~WbEn_q; end assign WB_DAT_O = ram_do; // Generic synchronous single-port RAM interface eth_spram_256x32 bd_ram ( .clk(WB_CLK_I), .rst(Reset), .ce(ram_ce), .we(ram_we), .oe(ram_oe), .addr(ram_addr), .di(ram_di), .do(ram_do) `ifdef ETH_BIST , .trst(trst), .SO(SO), .SI(SI), .shift_DR(shift_DR), .capture_DR(capture_DR), .extest(extest), .tck(tck) `endif ); assign ram_ce = 1'b1; assign ram_we = BDWrite & WbEn & WbEn_q | TxStatusWrite | RxStatusWrite; assign ram_oe = BDRead & WbEn & WbEn_q | TxEn & TxEn_q & (TxBDRead | TxPointerRead) | RxEn & RxEn_q & (RxBDRead | RxPointerRead); always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxEn_needed <=#Tp 1'b0; else if(~TxBDReady & r_TxEn & WbEn & ~WbEn_q) TxEn_needed <=#Tp 1'b1; else if(TxPointerRead & TxEn & TxEn_q) TxEn_needed <=#Tp 1'b0; end // Enabling access to the RAM for three devices. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) begin WbEn <=#Tp 1'b1; RxEn <=#Tp 1'b0; TxEn <=#Tp 1'b0; ram_addr <=#Tp 8'h0; ram_di <=#Tp 32'h0; BDRead <=#Tp 1'b0; BDWrite <=#Tp 1'b0; end else begin // Switching between three stages depends on enable signals case ({WbEn_q, RxEn_q, TxEn_q, RxEn_needed, TxEn_needed}) // synopsys parallel_case 5'b100_10, 5'b100_11 : begin WbEn <=#Tp 1'b0; RxEn <=#Tp 1'b1; // wb access stage and r_RxEn is enabled TxEn <=#Tp 1'b0; ram_addr <=#Tp RxBDAddress + RxPointerRead; ram_di <=#Tp RxBDDataIn; end 5'b100_01 : begin WbEn <=#Tp 1'b0; RxEn <=#Tp 1'b0; TxEn <=#Tp 1'b1; // wb access stage, r_RxEn is disabled but r_TxEn is enabled ram_addr <=#Tp TxBDAddress + TxPointerRead; ram_di <=#Tp TxBDDataIn; end 5'b010_00, 5'b010_10 : begin WbEn <=#Tp 1'b1; // RxEn access stage and r_TxEn is disabled RxEn <=#Tp 1'b0; TxEn <=#Tp 1'b0; ram_addr <=#Tp WB_ADR_I[9:2]; ram_di <=#Tp WB_DAT_I; BDWrite <=#Tp BDCs & WB_WE_I; BDRead <=#Tp BDCs & ~WB_WE_I; end 5'b010_01, 5'b010_11 : begin WbEn <=#Tp 1'b0; RxEn <=#Tp 1'b0; TxEn <=#Tp 1'b1; // RxEn access stage and r_TxEn is enabled ram_addr <=#Tp TxBDAddress + TxPointerRead; ram_di <=#Tp TxBDDataIn; end 5'b001_00, 5'b001_01, 5'b001_10, 5'b001_11 : begin WbEn <=#Tp 1'b1; // TxEn access stage (we always go to wb access stage) RxEn <=#Tp 1'b0; TxEn <=#Tp 1'b0; ram_addr <=#Tp WB_ADR_I[9:2]; ram_di <=#Tp WB_DAT_I; BDWrite <=#Tp BDCs & WB_WE_I; BDRead <=#Tp BDCs & ~WB_WE_I; end 5'b100_00 : begin WbEn <=#Tp 1'b0; // WbEn access stage and there is no need for other stages. WbEn needs to be switched off for a bit end 5'b000_00 : begin WbEn <=#Tp 1'b1; // Idle state. We go to WbEn access stage. RxEn <=#Tp 1'b0; TxEn <=#Tp 1'b0; ram_addr <=#Tp WB_ADR_I[9:2]; ram_di <=#Tp WB_DAT_I; BDWrite <=#Tp BDCs & WB_WE_I; BDRead <=#Tp BDCs & ~WB_WE_I; end endcase end end // Delayed stage signals always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) begin WbEn_q <=#Tp 1'b0; RxEn_q <=#Tp 1'b0; TxEn_q <=#Tp 1'b0; end else begin WbEn_q <=#Tp WbEn; RxEn_q <=#Tp RxEn; TxEn_q <=#Tp TxEn; end end // Changes for tx occur every second clock. Flop is used for this manner. always @ (posedge MTxClk or posedge Reset) begin if(Reset) Flop <=#Tp 1'b0; else if(TxDone | TxAbort | TxRetry_q) Flop <=#Tp 1'b0; else if(TxUsedData) Flop <=#Tp ~Flop; end wire ResetTxBDReady; assign ResetTxBDReady = TxDonePulse | TxAbortPulse | TxRetryPulse; // Latching READY status of the Tx buffer descriptor always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxBDReady <=#Tp 1'b0; else if(TxEn & TxEn_q & TxBDRead) TxBDReady <=#Tp ram_do[15] & (ram_do[31:16] > 4); // TxBDReady is sampled only once at the beginning. else // Only packets larger then 4 bytes are transmitted. if(ResetTxBDReady) TxBDReady <=#Tp 1'b0; end // Reading the Tx buffer descriptor assign StartTxBDRead = (TxRetry_wb | TxStatusWrite) & ~BlockingTxBDRead & ~TxBDReady; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxBDRead <=#Tp 1'b1; else if(StartTxBDRead) TxBDRead <=#Tp 1'b1; else if(TxBDReady) TxBDRead <=#Tp 1'b0; end // Reading Tx BD pointer assign StartTxPointerRead = TxBDRead & TxBDReady; // Reading Tx BD Pointer always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxPointerRead <=#Tp 1'b0; else if(StartTxPointerRead) TxPointerRead <=#Tp 1'b1; else if(TxEn_q) TxPointerRead <=#Tp 1'b0; end // Writing status back to the Tx buffer descriptor assign TxStatusWrite = (TxDone_wb | TxAbort_wb) & TxEn & TxEn_q & ~BlockingTxStatusWrite; // Status writing must occur only once. Meanwhile it is blocked. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) BlockingTxStatusWrite <=#Tp 1'b0; else if(TxStatusWrite) BlockingTxStatusWrite <=#Tp 1'b1; else if(~TxDone_wb & ~TxAbort_wb) BlockingTxStatusWrite <=#Tp 1'b0; end reg BlockingTxStatusWrite_sync1; reg BlockingTxStatusWrite_sync2; // Synchronizing BlockingTxStatusWrite to MTxClk always @ (posedge MTxClk or posedge Reset) begin if(Reset) BlockingTxStatusWrite_sync1 <=#Tp 1'b0; else BlockingTxStatusWrite_sync1 <=#Tp BlockingTxStatusWrite; end // Synchronizing BlockingTxStatusWrite to MTxClk always @ (posedge MTxClk or posedge Reset) begin if(Reset) BlockingTxStatusWrite_sync2 <=#Tp 1'b0; else BlockingTxStatusWrite_sync2 <=#Tp BlockingTxStatusWrite_sync1; end // TxBDRead state is activated only once. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) BlockingTxBDRead <=#Tp 1'b0; else if(StartTxBDRead) BlockingTxBDRead <=#Tp 1'b1; else if(~StartTxBDRead & ~TxBDReady) BlockingTxBDRead <=#Tp 1'b0; end // Latching status from the tx buffer descriptor // Data is avaliable one cycle after the access is started (at that time signal TxEn is not active) always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxStatus <=#Tp 4'h0; else if(TxEn & TxEn_q & TxBDRead) TxStatus <=#Tp ram_do[14:11]; end reg ReadTxDataFromMemory; wire WriteRxDataToMemory; reg MasterWbTX; reg MasterWbRX; reg [31:0] m_wb_adr_o; reg m_wb_cyc_o; reg m_wb_stb_o; reg [3:0] m_wb_sel_o; reg m_wb_we_o; wire TxLengthEq0; wire TxLengthLt4; reg BlockingIncrementTxPointer; reg [31:2] TxPointerMSB; reg [1:0] TxPointerLSB; reg [1:0] TxPointerLSB_rst; reg [31:2] RxPointerMSB; reg [1:0] RxPointerLSB_rst; wire RxBurstAcc; wire RxWordAcc; wire RxHalfAcc; wire RxByteAcc; //Latching length from the buffer descriptor; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxLength <=#Tp 16'h0; else if(TxEn & TxEn_q & TxBDRead) TxLength <=#Tp ram_do[31:16]; else if(MasterWbTX & m_wb_ack_i) begin if(TxLengthLt4) TxLength <=#Tp 16'h0; else if(TxPointerLSB_rst==2'h0) TxLength <=#Tp TxLength - 3'h4; // Length is subtracted at the data request else if(TxPointerLSB_rst==2'h1) TxLength <=#Tp TxLength - 3'h3; // Length is subtracted at the data request else if(TxPointerLSB_rst==2'h2) TxLength <=#Tp TxLength - 3'h2; // Length is subtracted at the data request else if(TxPointerLSB_rst==2'h3) TxLength <=#Tp TxLength - 3'h1; // Length is subtracted at the data request end end //Latching length from the buffer descriptor; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) LatchedTxLength <=#Tp 16'h0; else if(TxEn & TxEn_q & TxBDRead) LatchedTxLength <=#Tp ram_do[31:16]; end assign TxLengthEq0 = TxLength == 0; assign TxLengthLt4 = TxLength < 4; reg cyc_cleared; reg IncrTxPointer; // Latching Tx buffer pointer from buffer descriptor. Only 30 MSB bits are latched // because TxPointerMSB is only used for word-aligned accesses. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxPointerMSB <=#Tp 30'h0; else if(TxEn & TxEn_q & TxPointerRead) TxPointerMSB <=#Tp ram_do[31:2]; else if(IncrTxPointer & ~BlockingIncrementTxPointer) TxPointerMSB <=#Tp TxPointerMSB + 1'b1; // TxPointer is word-aligned end // Latching 2 MSB bits of the buffer descriptor. Since word accesses are performed, // valid data does not necesserly start at byte 0 (could be byte 0, 1, 2 or 3). This // signals are used for proper selection of the start byte (TxData and TxByteCnt) are // set by this two bits. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxPointerLSB[1:0] <=#Tp 0; else if(TxEn & TxEn_q & TxPointerRead) TxPointerLSB[1:0] <=#Tp ram_do[1:0]; end // Latching 2 MSB bits of the buffer descriptor. // After the read access, TxLength needs to be decremented for the number of the valid // bytes (1 to 4 bytes are valid in the first word). After the first read all bytes are // valid so this two bits are reset to zero. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxPointerLSB_rst[1:0] <=#Tp 0; else if(TxEn & TxEn_q & TxPointerRead) TxPointerLSB_rst[1:0] <=#Tp ram_do[1:0]; else if(MasterWbTX & m_wb_ack_i) // After first access pointer is word alligned TxPointerLSB_rst[1:0] <=#Tp 0; end reg [3:0] RxByteSel; wire MasterAccessFinished; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) BlockingIncrementTxPointer <=#Tp 0; else if(MasterAccessFinished) BlockingIncrementTxPointer <=#Tp 0; else if(IncrTxPointer) BlockingIncrementTxPointer <=#Tp 1'b1; end wire TxBufferAlmostFull; wire TxBufferFull; wire TxBufferEmpty; wire TxBufferAlmostEmpty; wire SetReadTxDataFromMemory; reg BlockReadTxDataFromMemory; assign SetReadTxDataFromMemory = TxEn & TxEn_q & TxPointerRead; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ReadTxDataFromMemory <=#Tp 1'b0; else if(TxLengthEq0 | TxAbortPacket | TxRetryPacket) ReadTxDataFromMemory <=#Tp 1'b0; else if(SetReadTxDataFromMemory) ReadTxDataFromMemory <=#Tp 1'b1; end wire ReadTxDataFromMemory_2 = ReadTxDataFromMemory & ~BlockReadTxDataFromMemory; wire [31:0] TxData_wb; wire ReadTxDataFromFifo_wb; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) BlockReadTxDataFromMemory <=#Tp 1'b0; else if((TxBufferAlmostFull | TxLength <= 4)& MasterWbTX) BlockReadTxDataFromMemory <=#Tp 1'b1; else if(ReadTxDataFromFifo_wb | TxDonePulse_q | TxAbortPacket | TxRetryPacket) BlockReadTxDataFromMemory <=#Tp 1'b0; end assign MasterAccessFinished = m_wb_ack_i | m_wb_err_i; wire [`ETH_TX_FIFO_CNT_WIDTH-1:0] txfifo_cnt; wire [`ETH_RX_FIFO_CNT_WIDTH-1:0] rxfifo_cnt; // Enabling master wishbone access to the memory for two devices TX and RX. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) begin MasterWbTX <=#Tp 1'b0; MasterWbRX <=#Tp 1'b0; m_wb_adr_o <=#Tp 32'h0; m_wb_cyc_o <=#Tp 1'b0; m_wb_stb_o <=#Tp 1'b0; m_wb_we_o <=#Tp 1'b0; m_wb_sel_o <=#Tp 4'h0; cyc_cleared<=#Tp 1'b0; IncrTxPointer<=#Tp 1'b0; end else begin // Switching between two stages depends on enable signals casex ({MasterWbTX, MasterWbRX, ReadTxDataFromMemory_2, WriteRxDataToMemory, MasterAccessFinished, cyc_cleared}) // synopsys parallel_case 6'b00_01_0_x, 6'b00_11_0_x : begin MasterWbTX <=#Tp 1'b0; // idle and master write is needed (data write to rx buffer) MasterWbRX <=#Tp 1'b1; m_wb_adr_o <=#Tp {RxPointerMSB, 2'h0}; m_wb_cyc_o <=#Tp 1'b1; m_wb_stb_o <=#Tp 1'b1; m_wb_we_o <=#Tp 1'b1; m_wb_sel_o <=#Tp RxByteSel; IncrTxPointer<=#Tp 1'b0; end 6'b00_10_0_x, 6'b00_10_1_x : begin MasterWbTX <=#Tp 1'b1; // idle and master read is needed (data read from tx buffer) MasterWbRX <=#Tp 1'b0; m_wb_adr_o <=#Tp {TxPointerMSB, 2'h0}; m_wb_cyc_o <=#Tp 1'b1; m_wb_stb_o <=#Tp 1'b1; m_wb_we_o <=#Tp 1'b0; m_wb_sel_o <=#Tp 4'hf; IncrTxPointer<=#Tp 1'b1; end 6'b10_10_0_1 : begin MasterWbTX <=#Tp 1'b1; // master read and master read is needed (data read from tx buffer) MasterWbRX <=#Tp 1'b0; m_wb_adr_o <=#Tp {TxPointerMSB, 2'h0}; m_wb_cyc_o <=#Tp 1'b1; m_wb_stb_o <=#Tp 1'b1; m_wb_we_o <=#Tp 1'b0; m_wb_sel_o <=#Tp 4'hf; cyc_cleared<=#Tp 1'b0; IncrTxPointer<=#Tp 1'b1; end 6'b01_01_0_1 : begin MasterWbTX <=#Tp 1'b0; // master write and master write is needed (data write to rx buffer) MasterWbRX <=#Tp 1'b1; m_wb_adr_o <=#Tp {RxPointerMSB, 2'h0}; m_wb_cyc_o <=#Tp 1'b1; m_wb_stb_o <=#Tp 1'b1; m_wb_we_o <=#Tp 1'b1; m_wb_sel_o <=#Tp RxByteSel; cyc_cleared<=#Tp 1'b0; IncrTxPointer<=#Tp 1'b0; end 6'b10_01_0_1, 6'b10_11_0_1 : begin MasterWbTX <=#Tp 1'b0; // master read and master write is needed (data write to rx buffer) MasterWbRX <=#Tp 1'b1; m_wb_adr_o <=#Tp {RxPointerMSB, 2'h0}; m_wb_cyc_o <=#Tp 1'b1; m_wb_stb_o <=#Tp 1'b1; m_wb_we_o <=#Tp 1'b1; m_wb_sel_o <=#Tp RxByteSel; cyc_cleared<=#Tp 1'b0; IncrTxPointer<=#Tp 1'b0; end 6'b01_10_0_1, 6'b01_11_0_1 : begin MasterWbTX <=#Tp 1'b1; // master write and master read is needed (data read from tx buffer) MasterWbRX <=#Tp 1'b0; m_wb_adr_o <=#Tp {TxPointerMSB, 2'h0}; m_wb_cyc_o <=#Tp 1'b1; m_wb_stb_o <=#Tp 1'b1; m_wb_we_o <=#Tp 1'b0; m_wb_sel_o <=#Tp 4'hf; cyc_cleared<=#Tp 1'b0; IncrTxPointer<=#Tp 1'b1; end 6'b10_10_1_0, 6'b01_01_1_0, 6'b10_01_1_0, 6'b10_11_1_0, 6'b01_10_1_0, 6'b01_11_1_0 : begin m_wb_cyc_o <=#Tp 1'b0; // whatever and master read or write is needed. We need to clear m_wb_cyc_o before next access is started m_wb_stb_o <=#Tp 1'b0; cyc_cleared<=#Tp 1'b1; IncrTxPointer<=#Tp 1'b0; end 6'b10_00_1_x, 6'b01_00_1_x : begin MasterWbTX <=#Tp 1'b0; // whatever and no master read or write is needed (ack or err comes finishing previous access) MasterWbRX <=#Tp 1'b0; m_wb_cyc_o <=#Tp 1'b0; m_wb_stb_o <=#Tp 1'b0; IncrTxPointer<=#Tp 1'b0; end 6'b10_00_0_1, 6'b01_00_0_1 : begin MasterWbTX <=#Tp 1'b0; // Between cyc_cleared request was cleared MasterWbRX <=#Tp 1'b0; m_wb_cyc_o <=#Tp 1'b0; m_wb_stb_o <=#Tp 1'b0; IncrTxPointer<=#Tp 1'b0; end default: // Don't touch begin MasterWbTX <=#Tp MasterWbTX; MasterWbRX <=#Tp MasterWbRX; m_wb_cyc_o <=#Tp m_wb_cyc_o; m_wb_stb_o <=#Tp m_wb_stb_o; m_wb_sel_o <=#Tp m_wb_sel_o; IncrTxPointer<=#Tp IncrTxPointer; end endcase end end wire TxFifoClear; assign TxFifoClear = (TxAbortPacket | TxRetryPacket); eth_fifo #(`ETH_TX_FIFO_DATA_WIDTH, `ETH_TX_FIFO_DEPTH, `ETH_TX_FIFO_CNT_WIDTH) tx_fifo ( .data_in(m_wb_dat_i), .data_out(TxData_wb), .clk(WB_CLK_I), .reset(Reset), .write(MasterWbTX & m_wb_ack_i), .read(ReadTxDataFromFifo_wb & ~TxBufferEmpty), .clear(TxFifoClear), .full(TxBufferFull), .almost_full(TxBufferAlmostFull), .almost_empty(TxBufferAlmostEmpty), .empty(TxBufferEmpty), .cnt(txfifo_cnt) ); reg StartOccured; reg TxStartFrm_sync1; reg TxStartFrm_sync2; reg TxStartFrm_syncb1; reg TxStartFrm_syncb2; // Start: Generation of the TxStartFrm_wb which is then synchronized to the MTxClk always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxStartFrm_wb <=#Tp 1'b0; else if(TxBDReady & ~StartOccured & (TxBufferFull | TxLengthEq0)) TxStartFrm_wb <=#Tp 1'b1; else if(TxStartFrm_syncb2) TxStartFrm_wb <=#Tp 1'b0; end // StartOccured: TxStartFrm_wb occurs only ones at the beginning. Then it's blocked. always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) StartOccured <=#Tp 1'b0; else if(TxStartFrm_wb) StartOccured <=#Tp 1'b1; else if(ResetTxBDReady) StartOccured <=#Tp 1'b0; end // Synchronizing TxStartFrm_wb to MTxClk always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxStartFrm_sync1 <=#Tp 1'b0; else TxStartFrm_sync1 <=#Tp TxStartFrm_wb; end always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxStartFrm_sync2 <=#Tp 1'b0; else TxStartFrm_sync2 <=#Tp TxStartFrm_sync1; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxStartFrm_syncb1 <=#Tp 1'b0; else TxStartFrm_syncb1 <=#Tp TxStartFrm_sync2; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxStartFrm_syncb2 <=#Tp 1'b0; else TxStartFrm_syncb2 <=#Tp TxStartFrm_syncb1; end always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxStartFrm <=#Tp 1'b0; else if(TxStartFrm_sync2) TxStartFrm <=#Tp 1'b1; else if(TxUsedData_q | ~TxStartFrm_sync2 & (TxRetry | TxAbort)) TxStartFrm <=#Tp 1'b0; end // End: Generation of the TxStartFrm_wb which is then synchronized to the MTxClk // TxEndFrm_wb: indicator of the end of frame always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxEndFrm_wb <=#Tp 1'b0; else if(TxLengthLt4 & TxBufferAlmostEmpty & TxUsedData) TxEndFrm_wb <=#Tp 1'b1; else if(TxRetryPulse | TxDonePulse | TxAbortPulse) TxEndFrm_wb <=#Tp 1'b0; end // Marks which bytes are valid within the word. assign TxValidBytes = TxLengthLt4 ? TxLength[1:0] : 2'b0; reg LatchValidBytes; reg LatchValidBytes_q; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) LatchValidBytes <=#Tp 1'b0; else if(TxLengthLt4 & TxBDReady) LatchValidBytes <=#Tp 1'b1; else LatchValidBytes <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) LatchValidBytes_q <=#Tp 1'b0; else LatchValidBytes_q <=#Tp LatchValidBytes; end // Latching valid bytes always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxValidBytesLatched <=#Tp 2'h0; else if(LatchValidBytes & ~LatchValidBytes_q) TxValidBytesLatched <=#Tp TxValidBytes; else if(TxRetryPulse | TxDonePulse | TxAbortPulse) TxValidBytesLatched <=#Tp 2'h0; end assign TxIRQEn = TxStatus[14]; assign WrapTxStatusBit = TxStatus[13]; assign PerPacketPad = TxStatus[12]; assign PerPacketCrcEn = TxStatus[11]; assign RxIRQEn = RxStatus[14]; assign WrapRxStatusBit = RxStatus[13]; // Temporary Tx and Rx buffer descriptor address assign TempTxBDAddress[7:0] = {8{ TxStatusWrite & ~WrapTxStatusBit}} & (TxBDAddress + 2'h2) ; // Tx BD increment or wrap (last BD) assign TempRxBDAddress[7:0] = {8{ WrapRxStatusBit}} & (r_TxBDNum<<1) | // Using first Rx BD {8{~WrapRxStatusBit}} & (RxBDAddress + 2'h2) ; // Using next Rx BD (incremenrement address) // Latching Tx buffer descriptor address always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxBDAddress <=#Tp 8'h0; else if(TxStatusWrite) TxBDAddress <=#Tp TempTxBDAddress; end // Latching Rx buffer descriptor address always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxBDAddress <=#Tp `ETH_TX_BD_NUM_DEF<<1; else if(TX_BD_NUM_Wr) // When r_TxBDNum is updated, RxBDAddress is also RxBDAddress <=#Tp WB_DAT_I[7:0]<<1; else if(RxStatusWrite) RxBDAddress <=#Tp TempRxBDAddress; end wire [8:0] TxStatusInLatched = {TxUnderRun, RetryCntLatched[3:0], RetryLimit, LateCollLatched, DeferLatched, CarrierSenseLost}; assign RxBDDataIn = {LatchedRxLength, 1'b0, RxStatus, 6'h0, RxStatusInLatched}; assign TxBDDataIn = {LatchedTxLength, 1'b0, TxStatus, 2'h0, TxStatusInLatched}; // Signals used for various purposes assign TxRetryPulse = TxRetry_wb & ~TxRetry_wb_q; assign TxDonePulse = TxDone_wb & ~TxDone_wb_q; assign TxAbortPulse = TxAbort_wb & ~TxAbort_wb_q; // Generating delayed signals always @ (posedge MTxClk or posedge Reset) begin if(Reset) begin TxAbort_q <=#Tp 1'b0; TxRetry_q <=#Tp 1'b0; TxUsedData_q <=#Tp 1'b0; end else begin TxAbort_q <=#Tp TxAbort; TxRetry_q <=#Tp TxRetry; TxUsedData_q <=#Tp TxUsedData; end end // Generating delayed signals always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) begin TxDone_wb_q <=#Tp 1'b0; TxAbort_wb_q <=#Tp 1'b0; TxRetry_wb_q <=#Tp 1'b0; TxDonePulse_q <=#Tp 1'b0; end else begin TxDone_wb_q <=#Tp TxDone_wb; TxAbort_wb_q <=#Tp TxAbort_wb; TxRetry_wb_q <=#Tp TxRetry_wb; TxDonePulse_q <=#Tp TxDonePulse; end end reg TxAbortPacketBlocked; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxAbortPacket <=#Tp 1'b0; else if(TxAbort_wb & (!TxAbortPacketBlocked) & (MasterWbTX & MasterAccessFinished | (!MasterWbTX))) TxAbortPacket <=#Tp 1'b1; else TxAbortPacket <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxAbortPacketBlocked <=#Tp 1'b0; else if(TxAbortPacket) TxAbortPacketBlocked <=#Tp 1'b1; else if(!TxAbort_wb & TxAbort_wb_q) TxAbortPacketBlocked <=#Tp 1'b0; end reg TxRetryPacketBlocked; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxRetryPacket <=#Tp 1'b0; else if(TxRetry_wb & (!TxRetryPacketBlocked) & (MasterWbTX & MasterAccessFinished | (!MasterWbTX))) TxRetryPacket <=#Tp 1'b1; else TxRetryPacket <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxRetryPacketBlocked <=#Tp 1'b0; else if(TxRetryPacket) TxRetryPacketBlocked <=#Tp 1'b1; else if(!TxRetry_wb & TxRetry_wb_q) TxRetryPacketBlocked <=#Tp 1'b0; end // Sinchronizing and evaluating tx data //assign SetGotData = (TxStartFrm_wb | NewTxDataAvaliable_wb & ~TxAbort_wb & ~TxRetry_wb) & ~WB_CLK_I; assign SetGotData = (TxStartFrm_wb); // Evaluating data. If abort or retry occured meanwhile than data is ignored. //assign GotDataEvaluate = GotDataSync3 & ~GotData & (~TxRetry & ~TxAbort | (TxRetry | TxAbort) & (TxStartFrm)); assign GotDataEvaluate = (~TxRetry & ~TxAbort | (TxRetry | TxAbort) & (TxStartFrm)); // Indication of the last word always @ (posedge MTxClk or posedge Reset) begin if(Reset) LastWord <=#Tp 1'b0; else if((TxEndFrm | TxAbort | TxRetry) & Flop) LastWord <=#Tp 1'b0; else if(TxUsedData & Flop & TxByteCnt == 2'h3) LastWord <=#Tp TxEndFrm_wb; end // Tx end frame generation always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxEndFrm <=#Tp 1'b0; else if(Flop & TxEndFrm | TxAbort | TxRetry_q) TxEndFrm <=#Tp 1'b0; else if(Flop & LastWord) begin case (TxValidBytesLatched) // synopsys parallel_case 1 : TxEndFrm <=#Tp TxByteCnt == 2'h0; 2 : TxEndFrm <=#Tp TxByteCnt == 2'h1; 3 : TxEndFrm <=#Tp TxByteCnt == 2'h2; 0 : TxEndFrm <=#Tp TxByteCnt == 2'h3; default : TxEndFrm <=#Tp 1'b0; endcase end end // Tx data selection (latching) always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxData <=#Tp 0; else if(TxStartFrm_sync2 & ~TxStartFrm) case(TxPointerLSB) // synopsys parallel_case 2'h0 : TxData <=#Tp TxData_wb[31:24]; // Big Endian Byte Ordering 2'h1 : TxData <=#Tp TxData_wb[23:16]; // Big Endian Byte Ordering 2'h2 : TxData <=#Tp TxData_wb[15:08]; // Big Endian Byte Ordering 2'h3 : TxData <=#Tp TxData_wb[07:00]; // Big Endian Byte Ordering endcase else if(TxStartFrm & TxUsedData & TxPointerLSB==2'h3) TxData <=#Tp TxData_wb[31:24]; // Big Endian Byte Ordering else if(TxUsedData & Flop) begin case(TxByteCnt) // synopsys parallel_case 0 : TxData <=#Tp TxDataLatched[31:24]; // Big Endian Byte Ordering 1 : TxData <=#Tp TxDataLatched[23:16]; 2 : TxData <=#Tp TxDataLatched[15:8]; 3 : TxData <=#Tp TxDataLatched[7:0]; endcase end end // Latching tx data always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxDataLatched[31:0] <=#Tp 32'h0; else if(TxStartFrm_sync2 & ~TxStartFrm | TxUsedData & Flop & TxByteCnt == 2'h3 | TxStartFrm & TxUsedData & Flop & TxByteCnt == 2'h0) TxDataLatched[31:0] <=#Tp TxData_wb[31:0]; end // Tx under run always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxUnderRun_wb <=#Tp 1'b0; else if(TxAbortPulse) TxUnderRun_wb <=#Tp 1'b0; else if(TxBufferEmpty & ReadTxDataFromFifo_wb) TxUnderRun_wb <=#Tp 1'b1; end reg TxUnderRun_sync1; // Tx under run always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxUnderRun_sync1 <=#Tp 1'b0; else if(TxUnderRun_wb) TxUnderRun_sync1 <=#Tp 1'b1; else if(BlockingTxStatusWrite_sync2) TxUnderRun_sync1 <=#Tp 1'b0; end // Tx under run always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxUnderRun <=#Tp 1'b0; else if(BlockingTxStatusWrite_sync2) TxUnderRun <=#Tp 1'b0; else if(TxUnderRun_sync1) TxUnderRun <=#Tp 1'b1; end // Tx Byte counter always @ (posedge MTxClk or posedge Reset) begin if(Reset) TxByteCnt <=#Tp 2'h0; else if(TxAbort_q | TxRetry_q) TxByteCnt <=#Tp 2'h0; else if(TxStartFrm & ~TxUsedData) case(TxPointerLSB) // synopsys parallel_case 2'h0 : TxByteCnt <=#Tp 2'h1; 2'h1 : TxByteCnt <=#Tp 2'h2; 2'h2 : TxByteCnt <=#Tp 2'h3; 2'h3 : TxByteCnt <=#Tp 2'h0; endcase else if(TxUsedData & Flop) TxByteCnt <=#Tp TxByteCnt + 1'b1; end // Start: Generation of the ReadTxDataFromFifo_tck signal and synchronization to the WB_CLK_I reg ReadTxDataFromFifo_sync1; reg ReadTxDataFromFifo_sync2; reg ReadTxDataFromFifo_sync3; reg ReadTxDataFromFifo_syncb1; reg ReadTxDataFromFifo_syncb2; reg ReadTxDataFromFifo_syncb3; always @ (posedge MTxClk or posedge Reset) begin if(Reset) ReadTxDataFromFifo_tck <=#Tp 1'b0; else if(TxStartFrm_sync2 & ~TxStartFrm | TxUsedData & Flop & TxByteCnt == 2'h3 & ~LastWord | TxStartFrm & TxUsedData & Flop & TxByteCnt == 2'h0) ReadTxDataFromFifo_tck <=#Tp 1'b1; else if(ReadTxDataFromFifo_syncb2 & ~ReadTxDataFromFifo_syncb3) ReadTxDataFromFifo_tck <=#Tp 1'b0; end // Synchronizing TxStartFrm_wb to MTxClk always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ReadTxDataFromFifo_sync1 <=#Tp 1'b0; else ReadTxDataFromFifo_sync1 <=#Tp ReadTxDataFromFifo_tck; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ReadTxDataFromFifo_sync2 <=#Tp 1'b0; else ReadTxDataFromFifo_sync2 <=#Tp ReadTxDataFromFifo_sync1; end always @ (posedge MTxClk or posedge Reset) begin if(Reset) ReadTxDataFromFifo_syncb1 <=#Tp 1'b0; else ReadTxDataFromFifo_syncb1 <=#Tp ReadTxDataFromFifo_sync2; end always @ (posedge MTxClk or posedge Reset) begin if(Reset) ReadTxDataFromFifo_syncb2 <=#Tp 1'b0; else ReadTxDataFromFifo_syncb2 <=#Tp ReadTxDataFromFifo_syncb1; end always @ (posedge MTxClk or posedge Reset) begin if(Reset) ReadTxDataFromFifo_syncb3 <=#Tp 1'b0; else ReadTxDataFromFifo_syncb3 <=#Tp ReadTxDataFromFifo_syncb2; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ReadTxDataFromFifo_sync3 <=#Tp 1'b0; else ReadTxDataFromFifo_sync3 <=#Tp ReadTxDataFromFifo_sync2; end assign ReadTxDataFromFifo_wb = ReadTxDataFromFifo_sync2 & ~ReadTxDataFromFifo_sync3; // End: Generation of the ReadTxDataFromFifo_tck signal and synchronization to the WB_CLK_I // Synchronizing TxRetry signal (synchronized to WISHBONE clock) always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxRetrySync1 <=#Tp 1'b0; else TxRetrySync1 <=#Tp TxRetry; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxRetry_wb <=#Tp 1'b0; else TxRetry_wb <=#Tp TxRetrySync1; end // Synchronized TxDone_wb signal (synchronized to WISHBONE clock) always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxDoneSync1 <=#Tp 1'b0; else TxDoneSync1 <=#Tp TxDone; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxDone_wb <=#Tp 1'b0; else TxDone_wb <=#Tp TxDoneSync1; end // Synchronizing TxAbort signal (synchronized to WISHBONE clock) always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxAbortSync1 <=#Tp 1'b0; else TxAbortSync1 <=#Tp TxAbort; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxAbort_wb <=#Tp 1'b0; else TxAbort_wb <=#Tp TxAbortSync1; end reg RxAbortSync1; reg RxAbortSync2; reg RxAbortSync3; reg RxAbortSync4; reg RxAbortSyncb1; reg RxAbortSyncb2; //assign StartRxBDRead = RxStatusWrite | RxAbortLatched; assign StartRxBDRead = RxStatusWrite | RxAbortSync3 & ~RxAbortSync4; // Reading the Rx buffer descriptor always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxBDRead <=#Tp 1'b1; else if(StartRxBDRead & ~RxReady) RxBDRead <=#Tp 1'b1; else if(RxBDReady) RxBDRead <=#Tp 1'b0; end // Reading of the next receive buffer descriptor starts after reception status is // written to the previous one. // Latching READY status of the Rx buffer descriptor always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxBDReady <=#Tp 1'b0; else if(RxPointerRead) RxBDReady <=#Tp 1'b0; else if(RxEn & RxEn_q & RxBDRead) RxBDReady <=#Tp ram_do[15]; // RxBDReady is sampled only once at the beginning end // Latching Rx buffer descriptor status // Data is avaliable one cycle after the access is started (at that time signal RxEn is not active) always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxStatus <=#Tp 2'h0; else if(RxEn & RxEn_q & RxBDRead) RxStatus <=#Tp ram_do[14:13]; end // RxReady generation always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxReady <=#Tp 1'b0; else if(ShiftEnded | RxAbortSync2 & ~RxAbortSync3) RxReady <=#Tp 1'b0; else if(RxEn & RxEn_q & RxPointerRead) RxReady <=#Tp 1'b1; end // Reading Rx BD pointer assign StartRxPointerRead = RxBDRead & RxBDReady; // Reading Tx BD Pointer always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxPointerRead <=#Tp 1'b0; else if(StartRxPointerRead) RxPointerRead <=#Tp 1'b1; else if(RxEn & RxEn_q) RxPointerRead <=#Tp 1'b0; end //Latching Rx buffer pointer from buffer descriptor; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxPointerMSB <=#Tp 30'h0; else if(RxEn & RxEn_q & RxPointerRead) RxPointerMSB <=#Tp ram_do[31:2]; else if(MasterWbRX & m_wb_ack_i) RxPointerMSB <=#Tp RxPointerMSB + 1; // Word access (always word access. m_wb_sel_o are used for selecting bytes) end //Latching last addresses from buffer descriptor (used as byte-half-word indicator); always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxPointerLSB_rst[1:0] <=#Tp 0; else if(MasterWbRX & m_wb_ack_i) // After first write all RxByteSel are active RxPointerLSB_rst[1:0] <=#Tp 0; else if(RxEn & RxEn_q & RxPointerRead) RxPointerLSB_rst[1:0] <=#Tp ram_do[1:0]; end always @ (RxPointerLSB_rst) begin case(RxPointerLSB_rst[1:0]) // synopsys parallel_case 2'h0 : RxByteSel[3:0] = 4'hf; 2'h1 : RxByteSel[3:0] = 4'h7; 2'h2 : RxByteSel[3:0] = 4'h3; 2'h3 : RxByteSel[3:0] = 4'h1; endcase end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxEn_needed <=#Tp 1'b0; else if(~RxReady & r_RxEn & WbEn & ~WbEn_q) RxEn_needed <=#Tp 1'b1; else if(RxPointerRead & RxEn & RxEn_q) RxEn_needed <=#Tp 1'b0; end // Reception status is written back to the buffer descriptor after the end of frame is detected. assign RxStatusWrite = ShiftEnded & RxEn & RxEn_q; reg RxStatusWriteLatched; reg RxStatusWrite_rck; always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxStatusWriteLatched <=#Tp 1'b0; else if(RxStatusWrite & ~RxStatusWrite_rck) RxStatusWriteLatched <=#Tp 1'b1; else if(RxStatusWrite_rck) RxStatusWriteLatched <=#Tp 1'b0; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxStatusWrite_rck <=#Tp 1'b0; else if(RxStatusWriteLatched) RxStatusWrite_rck <=#Tp 1'b1; else RxStatusWrite_rck <=#Tp 1'b0; end reg RxEnableWindow; // Indicating that last byte is being reveived always @ (posedge MRxClk or posedge Reset) begin if(Reset) LastByteIn <=#Tp 1'b0; else if(ShiftWillEnd & (&RxByteCnt) | RxAbort) LastByteIn <=#Tp 1'b0; else if(RxValid & RxReady & RxEndFrm & ~(&RxByteCnt) & RxEnableWindow) LastByteIn <=#Tp 1'b1; end reg ShiftEnded_rck; reg ShiftEndedSync1; reg ShiftEndedSync2; reg ShiftEndedSync3; reg ShiftEndedSync_c1; reg ShiftEndedSync_c2; wire StartShiftWillEnd; assign StartShiftWillEnd = LastByteIn | RxValid & RxEndFrm & (&RxByteCnt) & RxEnableWindow; // Indicating that data reception will end always @ (posedge MRxClk or posedge Reset) begin if(Reset) ShiftWillEnd <=#Tp 1'b0; else if(ShiftEnded_rck | RxAbort) ShiftWillEnd <=#Tp 1'b0; else if(StartShiftWillEnd) ShiftWillEnd <=#Tp 1'b1; end // Receive byte counter always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxByteCnt <=#Tp 2'h0; else if(ShiftEnded_rck | RxAbort) RxByteCnt <=#Tp 2'h0; else if(RxValid & RxStartFrm & RxReady) case(RxPointerLSB_rst) // synopsys parallel_case 2'h0 : RxByteCnt <=#Tp 2'h1; 2'h1 : RxByteCnt <=#Tp 2'h2; 2'h2 : RxByteCnt <=#Tp 2'h3; 2'h3 : RxByteCnt <=#Tp 2'h0; endcase else if(RxValid & RxEnableWindow & RxReady | LastByteIn) RxByteCnt <=#Tp RxByteCnt + 1'b1; end // Indicates how many bytes are valid within the last word always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxValidBytes <=#Tp 2'h1; else if(RxValid & RxStartFrm) case(RxPointerLSB_rst) // synopsys parallel_case 2'h0 : RxValidBytes <=#Tp 2'h1; 2'h1 : RxValidBytes <=#Tp 2'h2; 2'h2 : RxValidBytes <=#Tp 2'h3; 2'h3 : RxValidBytes <=#Tp 2'h0; endcase else if(RxValid & ~LastByteIn & ~RxStartFrm & RxEnableWindow) RxValidBytes <=#Tp RxValidBytes + 1; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxDataLatched1 <=#Tp 24'h0; else if(RxValid & RxReady & ~LastByteIn) if(RxStartFrm) begin case(RxPointerLSB_rst) // synopsys parallel_case 2'h0: RxDataLatched1[31:24] <=#Tp RxData; // Big Endian Byte Ordering 2'h1: RxDataLatched1[23:16] <=#Tp RxData; 2'h2: RxDataLatched1[15:8] <=#Tp RxData; 2'h3: RxDataLatched1 <=#Tp RxDataLatched1; endcase end else if (RxEnableWindow) begin case(RxByteCnt) // synopsys parallel_case 2'h0: RxDataLatched1[31:24] <=#Tp RxData; // Big Endian Byte Ordering 2'h1: RxDataLatched1[23:16] <=#Tp RxData; 2'h2: RxDataLatched1[15:8] <=#Tp RxData; 2'h3: RxDataLatched1 <=#Tp RxDataLatched1; endcase end end wire SetWriteRxDataToFifo; // Assembling data that will be written to the rx_fifo always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxDataLatched2 <=#Tp 32'h0; else if(SetWriteRxDataToFifo & ~ShiftWillEnd) RxDataLatched2 <=#Tp {RxDataLatched1[31:8], RxData}; // Big Endian Byte Ordering else if(SetWriteRxDataToFifo & ShiftWillEnd) case(RxValidBytes) // synopsys parallel_case 0 : RxDataLatched2 <=#Tp {RxDataLatched1[31:8], RxData}; // Big Endian Byte Ordering 1 : RxDataLatched2 <=#Tp {RxDataLatched1[31:24], 24'h0}; 2 : RxDataLatched2 <=#Tp {RxDataLatched1[31:16], 16'h0}; 3 : RxDataLatched2 <=#Tp {RxDataLatched1[31:8], 8'h0}; endcase end reg WriteRxDataToFifoSync1; reg WriteRxDataToFifoSync2; reg WriteRxDataToFifoSync3; // Indicating start of the reception process assign SetWriteRxDataToFifo = (RxValid & RxReady & ~RxStartFrm & RxEnableWindow & (&RxByteCnt)) | (RxValid & RxReady & RxStartFrm & (&RxPointerLSB_rst)) | (ShiftWillEnd & LastByteIn & (&RxByteCnt)); always @ (posedge MRxClk or posedge Reset) begin if(Reset) WriteRxDataToFifo <=#Tp 1'b0; else if(SetWriteRxDataToFifo & ~RxAbort) WriteRxDataToFifo <=#Tp 1'b1; else if(WriteRxDataToFifoSync2 | RxAbort) WriteRxDataToFifo <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) WriteRxDataToFifoSync1 <=#Tp 1'b0; else if(WriteRxDataToFifo) WriteRxDataToFifoSync1 <=#Tp 1'b1; else WriteRxDataToFifoSync1 <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) WriteRxDataToFifoSync2 <=#Tp 1'b0; else WriteRxDataToFifoSync2 <=#Tp WriteRxDataToFifoSync1; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) WriteRxDataToFifoSync3 <=#Tp 1'b0; else WriteRxDataToFifoSync3 <=#Tp WriteRxDataToFifoSync2; end wire WriteRxDataToFifo_wb; assign WriteRxDataToFifo_wb = WriteRxDataToFifoSync2 & ~WriteRxDataToFifoSync3; reg LatchedRxStartFrm; reg SyncRxStartFrm; reg SyncRxStartFrm_q; reg SyncRxStartFrm_q2; wire RxFifoReset; always @ (posedge MRxClk or posedge Reset) begin if(Reset) LatchedRxStartFrm <=#Tp 0; else if(RxStartFrm & ~SyncRxStartFrm_q) LatchedRxStartFrm <=#Tp 1; else if(SyncRxStartFrm_q) LatchedRxStartFrm <=#Tp 0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) SyncRxStartFrm <=#Tp 0; else if(LatchedRxStartFrm) SyncRxStartFrm <=#Tp 1; else SyncRxStartFrm <=#Tp 0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) SyncRxStartFrm_q <=#Tp 0; else SyncRxStartFrm_q <=#Tp SyncRxStartFrm; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) SyncRxStartFrm_q2 <=#Tp 0; else SyncRxStartFrm_q2 <=#Tp SyncRxStartFrm_q; end assign RxFifoReset = SyncRxStartFrm_q & ~SyncRxStartFrm_q2; eth_fifo #(`ETH_RX_FIFO_DATA_WIDTH, `ETH_RX_FIFO_DEPTH, `ETH_RX_FIFO_CNT_WIDTH) rx_fifo (.data_in(RxDataLatched2), .data_out(m_wb_dat_o), .clk(WB_CLK_I), .reset(Reset), .write(WriteRxDataToFifo_wb & ~RxBufferFull), .read(MasterWbRX & m_wb_ack_i), .clear(RxFifoReset), .full(RxBufferFull), .almost_full(), .almost_empty(RxBufferAlmostEmpty), .empty(RxBufferEmpty), .cnt(rxfifo_cnt) ); assign WriteRxDataToMemory = ~RxBufferEmpty; // Generation of the end-of-frame signal always @ (posedge MRxClk or posedge Reset) begin if(Reset) ShiftEnded_rck <=#Tp 1'b0; else if(~RxAbort & SetWriteRxDataToFifo & StartShiftWillEnd) ShiftEnded_rck <=#Tp 1'b1; else if(RxAbort | ShiftEndedSync_c1 & ShiftEndedSync_c2) ShiftEnded_rck <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ShiftEndedSync1 <=#Tp 1'b0; else ShiftEndedSync1 <=#Tp ShiftEnded_rck; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ShiftEndedSync2 <=#Tp 1'b0; else ShiftEndedSync2 <=#Tp ShiftEndedSync1; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ShiftEndedSync3 <=#Tp 1'b0; else if(ShiftEndedSync1 & ~ShiftEndedSync2) ShiftEndedSync3 <=#Tp 1'b1; else if(ShiftEnded) ShiftEndedSync3 <=#Tp 1'b0; end // Generation of the end-of-frame signal always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) ShiftEnded <=#Tp 1'b0; else if(ShiftEndedSync3 & MasterWbRX & m_wb_ack_i & RxBufferAlmostEmpty & ~ShiftEnded) ShiftEnded <=#Tp 1'b1; else if(RxStatusWrite) ShiftEnded <=#Tp 1'b0; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) ShiftEndedSync_c1 <=#Tp 1'b0; else ShiftEndedSync_c1 <=#Tp ShiftEndedSync2; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) ShiftEndedSync_c2 <=#Tp 1'b0; else ShiftEndedSync_c2 <=#Tp ShiftEndedSync_c1; end // Generation of the end-of-frame signal always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxEnableWindow <=#Tp 1'b0; else if(RxStartFrm) RxEnableWindow <=#Tp 1'b1; else if(RxEndFrm | RxAbort) RxEnableWindow <=#Tp 1'b0; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxAbortSync1 <=#Tp 1'b0; else RxAbortSync1 <=#Tp RxAbortLatched; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxAbortSync2 <=#Tp 1'b0; else RxAbortSync2 <=#Tp RxAbortSync1; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxAbortSync3 <=#Tp 1'b0; else RxAbortSync3 <=#Tp RxAbortSync2; end always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxAbortSync4 <=#Tp 1'b0; else RxAbortSync4 <=#Tp RxAbortSync3; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxAbortSyncb1 <=#Tp 1'b0; else RxAbortSyncb1 <=#Tp RxAbortSync2; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxAbortSyncb2 <=#Tp 1'b0; else RxAbortSyncb2 <=#Tp RxAbortSyncb1; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxAbortLatched <=#Tp 1'b0; else if(RxAbortSyncb2) RxAbortLatched <=#Tp 1'b0; else if(RxAbort) RxAbortLatched <=#Tp 1'b1; end always @ (posedge MRxClk or posedge Reset) begin if(Reset) LatchedRxLength[15:0] <=#Tp 16'h0; else if(LoadRxStatus) LatchedRxLength[15:0] <=#Tp RxLength[15:0]; end assign RxStatusIn = {RxOverrun, InvalidSymbol, DribbleNibble, ReceivedPacketTooBig, ShortFrame, LatchedCrcError, RxLateCollision}; always @ (posedge MRxClk or posedge Reset) begin if(Reset) RxStatusInLatched <=#Tp 'h0; else if(LoadRxStatus) RxStatusInLatched <=#Tp RxStatusIn; end // Rx overrun always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxOverrun <=#Tp 1'b0; else if(RxStatusWrite) RxOverrun <=#Tp 1'b0; else if(RxBufferFull & WriteRxDataToFifo_wb) RxOverrun <=#Tp 1'b1; end wire TxError; assign TxError = TxUnderRun | RetryLimit | LateCollLatched | CarrierSenseLost; wire RxError; assign RxError = |RxStatusInLatched[6:0]; // Tx Done Interrupt always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxB_IRQ <=#Tp 1'b0; else if(TxStatusWrite & TxIRQEn) TxB_IRQ <=#Tp ~TxError; else TxB_IRQ <=#Tp 1'b0; end // Tx Error Interrupt always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) TxE_IRQ <=#Tp 1'b0; else if(TxStatusWrite & TxIRQEn) TxE_IRQ <=#Tp TxError; else TxE_IRQ <=#Tp 1'b0; end // Rx Done Interrupt always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxB_IRQ <=#Tp 1'b0; else if(RxStatusWrite & RxIRQEn) RxB_IRQ <=#Tp ReceivedPacketGood & ~RxError; else RxB_IRQ <=#Tp 1'b0; end // Rx Error Interrupt always @ (posedge WB_CLK_I or posedge Reset) begin if(Reset) RxE_IRQ <=#Tp 1'b0; else if(RxStatusWrite & RxIRQEn) RxE_IRQ <=#Tp RxError; else RxE_IRQ <=#Tp 1'b0; end // Busy Interrupt reg Busy_IRQ_rck; reg Busy_IRQ_sync1; reg Busy_IRQ_sync2; reg Busy_IRQ_sync3; reg Busy_IRQ_syncb1; reg Busy_IRQ_syncb2; always @ (posedge MRxClk or posedge Reset) begin if(Reset) Busy_IRQ_rck <=#Tp 1'b0; else if(RxValid & RxStartFrm & ~RxReady) Busy_IRQ_rck <=#Tp 1'b1; else if(Busy_IRQ_syncb2) Busy_IRQ_rck <=#Tp 1'b0; end always @ (posedge WB_CLK_I) begin Busy_IRQ_sync1 <=#Tp Busy_IRQ_rck; Busy_IRQ_sync2 <=#Tp Busy_IRQ_sync1; Busy_IRQ_sync3 <=#Tp Busy_IRQ_sync2; end always @ (posedge MRxClk) begin Busy_IRQ_syncb1 <=#Tp Busy_IRQ_sync2; Busy_IRQ_syncb2 <=#Tp Busy_IRQ_syncb1; end assign Busy_IRQ = Busy_IRQ_sync2 & ~Busy_IRQ_sync3; // TX // bit 15 ready // bit 14 interrupt // bit 13 wrap // bit 12 pad // bit 11 crc // bit 10 last // bit 9 pause request (control frame) // bit 8 TxUnderRun // bit 7-4 RetryCntLatched // bit 3 retransmittion limit // bit 2 LateCollLatched // bit 1 DeferLatched // bit 0 CarrierSenseLost // RX // bit 15 od rx je empty // bit 14 od rx je interrupt // bit 13 od rx je wrap // bit 12 od rx je reserved // bit 11 od rx je reserved // bit 10 od rx je reserved // bit 9 od rx je reserved // bit 8 od rx je reserved // bit 7 od rx je Miss // bit 6 od rx je RxOverrun // bit 5 od rx je InvalidSymbol // bit 4 od rx je DribbleNibble // bit 3 od rx je ReceivedPacketTooBig // bit 2 od rx je ShortFrame // bit 1 od rx je LatchedCrcError // bit 0 od rx je RxLateCollision endmodule
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