Squashed B200 FPGA Source. Code from Josh Blum, Ian Buckley, and Matt Ettus.

Original-commit: 0df4b801a34697f2058b4a7b95e08d2a0576c9db

lib/gpif2/gpif2_to_fifo64.v

@@ -0,0 +1,118 @@
+//
+// Copyright 2012-2013 Ettus Research LLC
+//
+
+
+module gpif2_to_fifo64
+#(
+    parameter FIFO_SIZE = 9
+)
+(
+    //input interface
+    input gpif_clk, input gpif_rst,
+    input [31:0] i_tdata,
+    input i_tlast,
+    input i_tvalid,
+    output i_tready,
+    output fifo_has_space,
+    output fifo_nearly_full,
+ 
+    //output fifo interface
+    input fifo_clk, input fifo_rst,
+    output [63:0] o_tdata,
+    output o_tlast,
+    output o_tvalid,
+    input o_tready,
+
+    output bus_error,
+    output [159:0] debug
+);
+
+    wire [31:0] int_tdata;
+    wire int_tlast;
+    wire int_tvalid, int_tready;
+
+    wire [31:0] int0_tdata; wire int0_tlast, int0_tvalid, int0_tready;
+
+    //this fifo provides a space signal so we know a burst is possible
+    localparam BURST_SIZE = (FIFO_SIZE < 8)? FIFO_SIZE : 8;
+    wire [15:0] space;
+  
+   
+    assign fifo_has_space = space >= (1 << BURST_SIZE);
+    assign  fifo_nearly_full = (space < 6); // 5 spaces left.
+   
+    axi_fifo #(.WIDTH(33), .SIZE(0)) ingress_timing_fifo
+    (
+        .clk(gpif_clk), .reset(gpif_rst), .clear(1'b0),
+        .i_tdata({i_tlast, i_tdata}), .i_tvalid(i_tvalid), .i_tready(i_tready), .space(),
+        .o_tdata({int0_tlast, int0_tdata}), .o_tvalid(int0_tvalid), .o_tready(int0_tready), .occupied()
+    );
+    axi_fifo #(.WIDTH(33), .SIZE(BURST_SIZE)) min_read_buff
+    (
+        .clk(gpif_clk), .reset(gpif_rst), .clear(1'b0),
+        .i_tdata({int0_tlast, int0_tdata}), .i_tvalid(int0_tvalid), .i_tready(int0_tready), .space(space),
+        .o_tdata({int_tlast, int_tdata}), .o_tvalid(int_tvalid), .o_tready(int_tready), .occupied()
+    );
+  
+ reg 	   input_write_error;
+   
+   always @(posedge gpif_clk)  input_write_error <= i_tvalid & ~i_tready;
+   
+
+    wire [31:0] chk_tdata;
+    wire chk_tlast;
+    wire chk_tvalid, chk_tready;
+
+    axi_fifo_2clk #(.WIDTH(33), .SIZE(0/*SRL*/)) cross_clock_fifo
+    (
+        .reset(fifo_rst | gpif_rst),
+        .i_aclk(gpif_clk), .i_tdata({int_tlast, int_tdata}), .i_tvalid(int_tvalid), .i_tready(int_tready),
+        .o_aclk(fifo_clk), .o_tdata({chk_tlast, chk_tdata}), .o_tvalid(chk_tvalid), .o_tready(chk_tready)
+    );
+
+    wire [31:0] o32_tdata;
+    wire o32_tlast;
+    wire o32_tvalid, o32_tready;
+
+    //reframes a tlast from the vita header - and drops bad packets
+    //*
+    gpif2_error_checker #(.SIZE(FIFO_SIZE)) checker
+    (
+        .clk(fifo_clk), .reset(fifo_rst), .clear(1'b0),
+        .i_tdata(chk_tdata), .i_tlast(chk_tlast), .i_tvalid(chk_tvalid), .i_tready(chk_tready),
+        .o_tdata(o32_tdata), .o_tlast(o32_tlast), .o_tvalid(o32_tvalid), .o_tready(o32_tready),
+        .bus_error(bus_error), .debug(debug[63:0])
+    );
+    //*/
+    //assign o32_tdata = chk_tdata;
+    //assign o32_tlast = chk_tlast;
+    //assign o32_tvalid = chk_tvalid;
+    //assign chk_tready = o32_tready;
+
+    axi_fifo32_to_fifo64 fifo32_to_fifo64
+    (
+        .clk(fifo_clk), .reset(fifo_rst), .clear(1'b0),
+        .i_tdata(o32_tdata), .i_tuser(2'b0/*always 32 bits*/), .i_tlast(o32_tlast), .i_tvalid(o32_tvalid), .i_tready(o32_tready),
+        .o_tdata(o_tdata), .o_tuser(/*ignored cuz vita has len*/), .o_tlast(o_tlast), .o_tvalid(o_tvalid), .o_tready(o_tready)
+    );
+
+  assign debug[159:64] = {
+			  fifo_nearly_full, // 146
+			  space[9:0],      // 145:136
+			  input_write_error, // 135
+			  int_tlast,       // 134
+			  int_tready,      // 133
+			  int_tvalid,      // 132
+			  i_tlast,         // 131
+			  i_tready,    // 130
+			  fifo_has_space,        // 129
+			  i_tvalid,        // 128
+			  int_tdata[31:0], // 127:96
+			  i_tdata[31:0]    // 95:64
+			  };
+
+   
+   
+
+endmodule //fifo_to_gpif2