u1p: better way of reframing the packets

3 files changed, 83 insertions, 5 deletions

diff --git a/usrp2/gpif/gpif.v b/usrp2/gpif/gpif.v
index 8cac8b466..4f0ed233b 100644
--- a/usrp2/gpif/gpif.v
+++ b/usrp2/gpif/gpif.v
@@ -61,9 +61,18 @@ module gpif
       .ctrl_o(ctrl_data), .ctrl_src_rdy_o(ctrl_src_rdy), .ctrl_dst_rdy_i(ctrl_dst_rdy),
       .debug(debug_wr) );
 
+   // join vita packets which are longer than one frame, drop frame padding
+   wire [18:0] 	  refr_data;
+   wire 	  refr_src_rdy, refr_dst_rdy;
+   
+   packet_reframer tx_packet_reframer 
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_tx),
+      .data_i(tx19_data), .src_rdy_i(tx19_src_rdy), .dst_rdy_o(tx19_dst_rdy),
+      .data_o(refr_data), .src_rdy_o(refr_src_rdy), .dst_rdy_i(refr_dst_rdy));
+
    fifo19_to_fifo36 #(.LE(1)) f19_to_f36
      (.clk(fifo_clk), .reset(fifo_rst), .clear(0),
-      .f19_datain(tx19_data), .f19_src_rdy_i(tx19_src_rdy), .f19_dst_rdy_o(tx19_dst_rdy),
+      .f19_datain(refr_data), .f19_src_rdy_i(refr_src_rdy), .f19_dst_rdy_o(refr_dst_rdy),
       .f36_dataout(tx36_data), .f36_src_rdy_o(tx36_src_rdy), .f36_dst_rdy_i(tx36_dst_rdy));
    
    fifo_cascade #(.WIDTH(36), .SIZE(TXFIFOSIZE)) tx_fifo36
diff --git a/usrp2/gpif/gpif_wr_tb.v b/usrp2/gpif/gpif_wr_tb.v
index 6cfa13744..134365c87 100644
--- a/usrp2/gpif/gpif_wr_tb.v
+++ b/usrp2/gpif/gpif_wr_tb.v
@@ -26,6 +26,9 @@ module gpif_wr_tb();
    initial #1000 sys_rst = 0;
    always #64 gpif_clk <= ~gpif_clk;
    always #47.9 sys_clk <= ~sys_clk;
+
+   wire [18:0] data_int;
+   wire        src_rdy_int, dst_rdy_int;
    
    gpif_wr gpif_write
      (.gpif_clk(gpif_clk), .gpif_rst(gpif_rst), 
@@ -33,9 +36,14 @@ module gpif_wr_tb();
       .gpif_full_d(DF), .gpif_full_c(CF),
       
       .sys_clk(sys_clk), .sys_rst(sys_rst),
-      .data_o(data_o), .src_rdy_o(src_rdy), .dst_rdy_i(dst_rdy),
+      .data_o(data_int), .src_rdy_o(src_rdy_int), .dst_rdy_i(dst_rdy_int),
       .ctrl_o(ctrl_o), .ctrl_src_rdy_o(ctrl_src_rdy), .ctrl_dst_rdy_i(ctrl_dst_rdy) );
 
+   packet_reframer tx_packet_reframer 
+     (.clk(sys_clk), .reset(sys_rst), .clear(0),
+      .data_i(data_int), .src_rdy_i(src_rdy_int), .dst_rdy_o(dst_rdy_int),
+      .data_o(data_o), .src_rdy_o(src_rdy), .dst_rdy_i(dst_rdy));
+
    always @(posedge sys_clk)
      if(ctrl_src_rdy & ctrl_dst_rdy)
        $display("CTRL: %x",ctrl_o);
@@ -56,7 +64,7 @@ module gpif_wr_tb();
 	repeat (1)
 	  begin
 	     WR <= 1;
-	     gpif_data <= 150;  // Length
+	     gpif_data <= 10;  // Length
 	     @(posedge gpif_clk);
 	     gpif_data <= 16'h00;
 	     @(posedge gpif_clk);
@@ -69,14 +77,13 @@ module gpif_wr_tb();
 	     repeat (20)
 	       @(posedge gpif_clk);
 	     WR <= 1;
-	     gpif_data <= 16'hFF;
+	     gpif_data <= 16'h5;
 	     @(posedge gpif_clk);
 	     repeat(254)
 	       begin
 		  gpif_data <= gpif_data - 1;
 		  @(posedge gpif_clk);
 	       end
-	     
 	  end
      end // initial begin
    
diff --git a/usrp2/gpif/packet_reframer.v b/usrp2/gpif/packet_reframer.v
new file mode 100644
index 000000000..336c36369
--- /dev/null
+++ b/usrp2/gpif/packet_reframer.v
@@ -0,0 +1,62 @@
+
+// Join vita packets longer than one GPIF frame, drop padding on short frames
+
+module packet_reframer
+  (input clk, input reset, input clear,
+   input [18:0] data_i,
+   input src_rdy_i,
+   output dst_rdy_o,
+   output [18:0] data_o,
+   output src_rdy_o,
+   input dst_rdy_i);
+
+   reg [1:0] state;
+   reg [15:0] length;
+   
+   localparam RF_IDLE = 0;
+   localparam RF_PKT = 1;
+   localparam RF_DUMP = 2;
+   
+   always @(posedge clk)
+     if(reset | clear)
+       state <= 0;
+     else
+       if(src_rdy_i & dst_rdy_i)
+	 case(state)
+	   RF_IDLE :
+	     begin
+		length <= {data_i[14:0],1'b0};
+		state <= RF_PKT;
+	     end
+	   RF_PKT :
+	     begin
+		if(length == 2)
+		  if(data_i[17])
+		    state <= RF_IDLE;
+		  else
+		    state <= RF_DUMP;
+		else
+		  length <= length - 1;
+	     end
+	   RF_DUMP :
+	     if(data_i[17])
+	       state <= RF_IDLE;
+	   default :
+	     state<= RF_IDLE;
+	 endcase // case (state)
+   
+   assign dst_rdy_o = dst_rdy_i; // this is a little pessimistic but ok
+   assign src_rdy_o = src_rdy_i & (state != RF_DUMP);
+   
+   wire occ_out = 0;
+   wire eof_out = (state == RF_PKT) & (length == 2);
+   wire sof_out = (state == RF_IDLE);
+   wire [15:0] data_out = data_i[15:0];
+   assign data_o = {occ_out, eof_out, sof_out, data_out};
+   
+      
+endmodule // packet_reframer
+
+
+
+