[Commit-gnuradio] r10721 - gnuradio/trunk/usrp2/fpga/simple_gemac

[matt]

Author: matt
Date: 2009-03-31 12:03:20 -0600 (Tue, 31 Mar 2009)
New Revision: 10721

Added:
   gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_rx.v
Modified:
   gnuradio/trunk/usrp2/fpga/simple_gemac/flow_ctrl_tx.v
   gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac.v
   gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tb.v
   gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tx.v
Log:
we now inhibit our own sending when a received pause frame comes.  _rx.v is 
currently only a skeleton for testing pause


Modified: gnuradio/trunk/usrp2/fpga/simple_gemac/flow_ctrl_tx.v
===================================================================
--- gnuradio/trunk/usrp2/fpga/simple_gemac/flow_ctrl_tx.v       2009-03-31 
08:14:22 UTC (rev 10720)
+++ gnuradio/trunk/usrp2/fpga/simple_gemac/flow_ctrl_tx.v       2009-03-31 
18:03:20 UTC (rev 10721)
@@ -11,13 +11,16 @@
    input        pause_quanta_val,
    // MAC_tx_ctrl
    output       pause_apply,
-   input        pause_quanta_sub);
+   input        paused);
      
    // 
******************************************************************************  
      
    // Inhibit our TX from transmitting because they sent us a PAUSE frame
    // 
******************************************************************************
 
-   reg [15:0]  pause_quanta_counter;
+   // Pauses are in units of 512 bit times, or 64 bytes/clock cycles, and can 
be
+   //   as big as 16 bits, so 22 bits are needed for the counter
+   
+   reg [15+6:0] pause_quanta_counter;
    reg                 pqval_d1, pqval_d2;             
 
    always @(posedge tx_clk) pqval_d1 <= pause_quanta_val;
@@ -27,8 +30,8 @@
      if (rst)
        pause_quanta_counter <= 0;
      else if (pqval_d1 & ~pqval_d2)
-       pause_quanta_counter <= pause_quanta; 
-     else if((pause_quanta_counter!=0) & pause_quanta_sub)
+       pause_quanta_counter <= {pause_quanta, 6'b0}; 
+     else if((pause_quanta_counter!=0) & paused)
        pause_quanta_counter <= pause_quanta_counter - 1;
 
    assign      pause_apply = tx_pause_en & (pause_quanta_counter != 0);

Modified: gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac.v
===================================================================
--- gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac.v       2009-03-31 
08:14:22 UTC (rev 10720)
+++ gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac.v       2009-03-31 
18:03:20 UTC (rev 10721)
@@ -31,24 +31,24 @@
       .tx_clk(tx_clk), .tx_data(tx_data), .tx_valid(tx_valid), 
.tx_error(tx_error), .tx_ack(tx_ack),
       .ifg(SGE_IFG), .mac_addr(48'hF1_F2_F3_F4_F5_F6),
       .pause_req(pause_req), .pause_time(pause_time),  // We request flow 
control
-      .pause_apply(pause_apply), .pause_applied(pause_applied)  // We respect 
flow control
+      .pause_apply(pause_apply), .paused(paused)  // We respect flow control
       );
-/*
+
    simple_gemac_rx simple_gemac_rx
      (.reset(rst_rxclk),
       .GMII_RX_CLK(GMII_RX_CLK), .GMII_RX_DV(GMII_RX_DV), 
       .GMII_RX_ER(GMII_RX_ER), .GMII_RXD(GMII_RXD),
       .rx_clk(rx_clk), .rx_data(rx_data), .rx_valid(rx_valid), 
.rx_error(rx_error), .rx_ack(rx_ack),
-      .pause_quanta_rcvd(pause_qanta_rcvd), .pause_rcvd(pause_rcvd) 
+      .pause_quanta_rcvd(pause_quanta_rcvd), .pause_rcvd(pause_rcvd) 
       );
-  */ 
+
    flow_ctrl_tx flow_ctrl_tx
-     (.rst(reset_txclk), .tx_clk(tx_clk),
+     (.rst(rst_txclk), .tx_clk(tx_clk),
       .tx_pause_en(SGE_RESPECT_FLOW_CTRL),
       .pause_quanta(pause_quanta_rcvd), // 16 bit value
       .pause_quanta_val(pause_rcvd),
       .pause_apply(pause_apply),
-      .pause_quanta_sub(pause_applied)
+      .paused(paused)
       );
 
    

Added: gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_rx.v
===================================================================
--- gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_rx.v                    
        (rev 0)
+++ gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_rx.v    2009-03-31 
18:03:20 UTC (rev 10721)
@@ -0,0 +1,34 @@
+
+
+module simple_gemac_rx
+  (input clk125, input reset,
+   input GMII_RX_CLK, input GMII_RX_DV, input GMII_RX_ER, input [7:0] GMII_RXD,
+   output rx_clk, output [7:0] rx_data, output rx_valid, output rx_error, 
output rx_ack,
+   output reg [15:0] pause_quanta_rcvd, output reg pause_rcvd );
+
+   
+   
+   initial 
+     begin
+       pause_rcvd    <= 0;
+       pause_quanta_rcvd  = 10;
+       #50000 pause_rcvd <= 1;
+       @(posedge rx_clk)
+         pause_rcvd <= 0;
+       repeat (100)
+         @(posedge rx_clk);
+       pause_quanta_rcvd <= 15;
+       pause_rcvd        <= 1;
+       @(posedge rx_clk)
+         pause_rcvd <= 0;
+       repeat (1200)
+         @(posedge rx_clk);
+       pause_rcvd        <= 1;
+       @(posedge rx_clk)
+         pause_rcvd <= 0;
+       
+     end
+   
+   assign rx_clk          = GMII_RX_CLK;
+   
+endmodule // simple_gemac_rx

Modified: gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tb.v
===================================================================
--- gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tb.v    2009-03-31 
08:14:22 UTC (rev 10720)
+++ gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tb.v    2009-03-31 
18:03:20 UTC (rev 10721)
@@ -9,7 +9,7 @@
    initial #1000 reset = 0;
    always #50 clk = ~clk;
 
-   wire GMII_RX_DV, GMII_RX_ER, GMII_TX_EN, GMII_TX_ER;
+   wire GMII_RX_DV, GMII_RX_ER, GMII_TX_EN, GMII_TX_ER, GMII_GTX_CLK;
    wire [7:0] GMII_RXD, GMII_TXD;
 
    wire rx_valid, rx_error, rx_ack;
@@ -20,8 +20,14 @@
    reg [7:0] tx_data;
    
    wire [15:0] pause_time = 16'hBEEF;
-   reg pause_req = 0;
+   reg pause_req     = 0;
+
+   reg GMII_RX_CLK;
+   always @(GMII_GTX_CLK)
+     GMII_RX_CLK <= #30 GMII_GTX_CLK;
    
+//   wire GMII_RX_CLK  = #30 GMII_GTX_CLK;
+   
    simple_gemac simple_gemac
      (.clk125(clk),  .reset(reset),
       .GMII_GTX_CLK(GMII_GTX_CLK), .GMII_TX_EN(GMII_TX_EN),  

Modified: gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tx.v
===================================================================
--- gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tx.v    2009-03-31 
08:14:22 UTC (rev 10720)
+++ gnuradio/trunk/usrp2/fpga/simple_gemac/simple_gemac_tx.v    2009-03-31 
18:03:20 UTC (rev 10721)
@@ -5,7 +5,7 @@
    output tx_clk, input [7:0] tx_data, input tx_valid, input tx_error, output 
tx_ack,
    input [7:0] ifg, input [47:0] mac_addr,
    input pause_req, input [15:0] pause_time,
-   input pause_apply, output pause_applied
+   input pause_apply, output reg paused
    );
 
    reg tx_en_pre, tx_er_pre;
@@ -72,7 +72,7 @@
           if(~in_ifg)
             if(send_pause)
               tx_state <= TX_PAUSE;
-            else if(tx_valid)
+            else if(tx_valid & ~pause_apply)
               tx_state <= TX_PREAMBLE;
         TX_FIRSTBYTE :
           if(tx_error)
@@ -223,6 +223,15 @@
            GMII_TXD <= txd_pre;
        endcase // case (tx_state)
      end
+
+   // report that we are paused only when we get back to IDLE
+   always @(posedge tx_clk)
+     if(reset)
+       paused       <= 0;
+     else if(~pause_apply)
+       paused       <= 0;
+     else if(tx_state == TX_IDLE)
+       paused       <= 1;
    
 endmodule // simple_gemac_tx