Merge branch 'fpga_memory_reorg' into usrp2/new_reg_map

5 files changed, 160 insertions, 5 deletions

diff --git a/fpga/usrp2/simple_gemac/Makefile.srcs b/fpga/usrp2/simple_gemac/Makefile.srcs
index b82e64208..7bcc58c91 100644
--- a/fpga/usrp2/simple_gemac/Makefile.srcs
+++ b/fpga/usrp2/simple_gemac/Makefile.srcs
@@ -24,4 +24,6 @@ miim/eth_miim.v \
 miim/eth_clockgen.v \
 miim/eth_outputcontrol.v \
 miim/eth_shiftreg.v \
+ethtx_realign.v \
+ethrx_realign.v \
 ))
diff --git a/fpga/usrp2/simple_gemac/ethrx_realign.v b/fpga/usrp2/simple_gemac/ethrx_realign.v
new file mode 100644
index 000000000..0a369c914
--- /dev/null
+++ b/fpga/usrp2/simple_gemac/ethrx_realign.v
@@ -0,0 +1,72 @@
+
+// NOTE:  Will not work with single-line frames
+
+module ethrx_realign
+   (input clk, input reset, input clear,
+    input [35:0] datain, input src_rdy_i, output dst_rdy_o,
+    output [35:0] dataout, output src_rdy_o, input dst_rdy_i);
+
+   reg [1:0] 	  state;
+   reg [15:0] 	  held;
+   reg [1:0] 	  held_occ;
+	  
+   wire 	  xfer_in = src_rdy_i & dst_rdy_o;
+   wire 	  xfer_out = src_rdy_o & dst_rdy_i;
+
+   wire 	  sof_in = datain[32];
+   wire 	  eof_in = datain[33];
+   wire [1:0] 	  occ_in = datain[35:34];
+   wire 	  sof_out, eof_out;
+   wire [1:0] 	  occ_out;
+      
+   always @(posedge clk)
+     if(reset | clear)
+       begin
+	  held <= 0;
+	  held_occ <= 0;
+       end
+     else if(xfer_in)
+       begin
+	  held <= datain[15:0];
+	  held_occ <= datain[35:34];
+       end
+   
+   localparam RE_IDLE = 0;
+   localparam RE_HELD = 1;
+   localparam RE_DONE = 2;
+
+   always @(posedge clk)
+     if(reset | clear)
+       state <= RE_IDLE;
+     else
+       case(state)
+	 RE_IDLE :
+	   if(src_rdy_i & dst_rdy_i)
+	      if(eof_in)
+		state <= RE_DONE;
+	      else
+		state <= RE_HELD;
+
+	 RE_HELD :
+	   if(src_rdy_i & dst_rdy_i & eof_in)
+	     if((occ_in==0)|(occ_in==3))
+	       state <= RE_DONE;
+	     else
+	       state <= RE_IDLE;
+
+	 RE_DONE :
+	   if(dst_rdy_i)
+	     state <= RE_IDLE;
+	 
+       endcase // case (state)
+   
+   
+   assign sof_out = (state == RE_IDLE);
+   assign eof_out = (state == RE_DONE) | (occ_in == 1) | (occ_in == 2);
+   assign occ_out = (state == RE_DONE) ? ((held_occ == 3) ? 1 : 2) :
+		    (occ_in == 1) ? 3 : 0;
+   		    
+   assign dataout = {occ_out,eof_out,sof_out,held,datain[31:16]};
+   assign src_rdy_o = (state == RE_DONE) | src_rdy_i;
+   assign dst_rdy_o = dst_rdy_i & ((state == RE_IDLE)|(state == RE_HELD));
+endmodule // ethrx_realign
diff --git a/fpga/usrp2/simple_gemac/ethtx_realign.v b/fpga/usrp2/simple_gemac/ethtx_realign.v
new file mode 100644
index 000000000..be53abf4c
--- /dev/null
+++ b/fpga/usrp2/simple_gemac/ethtx_realign.v
@@ -0,0 +1,77 @@
+
+////////////////////////////////////////////////////////////////////////
+// Ethernet TX - Realign
+//
+// - removes a 2-byte pad from the front a fifo36 stream
+// - occupancy is preserved
+//
+
+module ethtx_realign
+   (input clk, input reset, input clear,
+    input [35:0] datain, input src_rdy_i, output dst_rdy_o,
+    output [35:0] dataout, output src_rdy_o, input dst_rdy_i);
+
+   reg [1:0] 	  state;
+   reg [15:0] 	  held;
+   reg [1:0] 	  held_occ;
+   reg 		  held_sof;
+   
+   wire 	  xfer_in = src_rdy_i & dst_rdy_o;
+   wire 	  xfer_out = src_rdy_o & dst_rdy_i;
+
+   wire 	  sof_in = datain[32];
+   wire 	  eof_in = datain[33];
+   wire [1:0] 	  occ_in = datain[35:34];
+   wire 	  occ_low = occ_in[1] ^ occ_in[0]; //occ is 1 or 2
+
+   always @(posedge clk)
+     if(reset | clear)
+       begin
+	  held <= 0;
+	  held_occ <= 0;
+	  held_sof <= 0;
+       end
+     else if(xfer_in)
+       begin
+	  held <= datain[15:0];
+	  held_occ <= occ_in;
+	  held_sof <= sof_in;
+       end
+   
+   localparam RE_IDLE = 0;
+   localparam RE_HELD = 1;
+   localparam RE_DONE = 2;
+
+   always @(posedge clk)
+     if(reset | clear)
+       state <= RE_IDLE;
+     else
+       case(state)
+	 RE_IDLE :
+	   if(xfer_in & eof_in)
+	     state <= RE_DONE;
+	   else if(xfer_in & sof_in)
+	     state <= RE_HELD;
+
+	 RE_HELD :
+	   if(xfer_in & xfer_out & eof_in)
+	     if(occ_low)
+	       state <= RE_IDLE;
+	     else
+	       state <= RE_DONE;
+
+	 RE_DONE :
+	   if(xfer_out)
+	     state <= RE_IDLE;
+	 
+       endcase // case (state)
+
+   wire sof_out = held_sof;
+   wire eof_out = (state == RE_HELD)? (eof_in & occ_low) : (state == RE_DONE);
+   wire [1:0] occ_out = ((state == RE_DONE)? held_occ : occ_in) ^ 2'b10; //(occ + 2)%4
+
+   assign dataout = {occ_out,eof_out,sof_out,held,datain[31:16]};
+   assign src_rdy_o = (state == RE_HELD)? src_rdy_i : (state == RE_DONE);
+   assign dst_rdy_o = (state == RE_HELD)? dst_rdy_i : (state == RE_IDLE);
+
+endmodule // ethtx_realign
diff --git a/fpga/usrp2/simple_gemac/simple_gemac_wrapper.v b/fpga/usrp2/simple_gemac/simple_gemac_wrapper.v
index b783729d5..8390eb2c6 100644
--- a/fpga/usrp2/simple_gemac/simple_gemac_wrapper.v
+++ b/fpga/usrp2/simple_gemac/simple_gemac_wrapper.v
@@ -106,17 +106,22 @@ module simple_gemac_wrapper
    // TX FIFO Chain
    wire 	  tx_ll_sof, tx_ll_eof, tx_ll_src_rdy, tx_ll_dst_rdy;
    wire [7:0] 	  tx_ll_data;
-   wire [35:0] 	  tx_f36_data_int1;
-   wire 	  tx_f36_src_rdy_int1, tx_f36_dst_rdy_int1;
+   wire [35:0] 	  tx_f36_data_int1, tx_f36_data_int2;
+   wire 	  tx_f36_src_rdy_int1, tx_f36_dst_rdy_int1, tx_f36_src_rdy_int2, tx_f36_dst_rdy_int2;
    
    fifo_2clock_cascade #(.WIDTH(36), .SIZE(TXFIFOSIZE)) tx_2clk_fifo
      (.wclk(sys_clk), .datain(tx_f36_data), .src_rdy_i(tx_f36_src_rdy), .dst_rdy_o(tx_f36_dst_rdy), .space(),
       .rclk(tx_clk), .dataout(tx_f36_data_int1), .src_rdy_o(tx_f36_src_rdy_int1), .dst_rdy_i(tx_f36_dst_rdy_int1), .occupied(), 
       .arst(reset));
-   
+
+   ethtx_realign ethtx_realign
+     (.clk(tx_clk), .reset(tx_reset), .clear(clear),
+      .datain(tx_f36_data_int1), .src_rdy_i(tx_f36_src_rdy_int1), .dst_rdy_o(tx_f36_dst_rdy_int1),
+      .dataout(tx_f36_data_int2), .src_rdy_o(tx_f36_src_rdy_int2), .dst_rdy_i(tx_f36_dst_rdy_int2) );
+     
    fifo36_to_ll8 fifo36_to_ll8
      (.clk(tx_clk), .reset(tx_reset), .clear(clear),
-      .f36_data(tx_f36_data_int1), .f36_src_rdy_i(tx_f36_src_rdy_int1), .f36_dst_rdy_o(tx_f36_dst_rdy_int1),
+      .f36_data(tx_f36_data_int2), .f36_src_rdy_i(tx_f36_src_rdy_int2), .f36_dst_rdy_o(tx_f36_dst_rdy_int2),
       .ll_data(tx_ll_data), .ll_sof(tx_ll_sof), .ll_eof(tx_ll_eof),
       .ll_src_rdy(tx_ll_src_rdy), .ll_dst_rdy(tx_ll_dst_rdy));
 
diff --git a/fpga/usrp2/simple_gemac/simple_gemac_wrapper19.v b/fpga/usrp2/simple_gemac/simple_gemac_wrapper19.v
index c155b7d41..2ac8b9be1 100644
--- a/fpga/usrp2/simple_gemac/simple_gemac_wrapper19.v
+++ b/fpga/usrp2/simple_gemac/simple_gemac_wrapper19.v
@@ -90,7 +90,6 @@ module simple_gemac_wrapper19
       .datain(rx_f19_data_int1), .src_rdy_i(rx_f19_src_rdy_int1), .dst_rdy_o(rx_f19_dst_rdy_int1),
       .dataout(rx_f19_data_int2), .src_rdy_o(rx_f19_src_rdy_int2), .dst_rdy_i(rx_f19_dst_rdy_int2) );
 
-   //fifo_2clock_cascade #(.WIDTH(19), .SIZE(RXFIFOSIZE)) rx_2clk_fifo
    fifo_2clock_cascade #(.WIDTH(36), .SIZE(RXFIFOSIZE)) rx_2clk_fifo
      (.wclk(rx_clk), .datain(rx_f19_data_int2), 
       .src_rdy_i(rx_f19_src_rdy_int2), .dst_rdy_o(rx_f19_dst_rdy_int2), .space(rx_fifo_space),