abstract out the crossbar functionality

1 files changed, 40 insertions, 0 deletions

diff --git a/usrp2/fifo/crossbar36.v b/usrp2/fifo/crossbar36.v
new file mode 100644
index 000000000..d90f5659c
--- /dev/null
+++ b/usrp2/fifo/crossbar36.v
@@ -0,0 +1,40 @@
+
+
+module crossbar36
+  (input clk, input reset, input clear,
+   input cross,
+   input [35:0] data0_i, input src0_rdy_i, output dst0_rdy_o,
+   input [35:0] data1_i, input src1_rdy_i, output dst1_rdy_o,
+   output [35:0] data0_o, output src0_rdy_o, input dst0_rdy_i,
+   output [35:0] data1_o, output src1_rdy_o, input dst1_rdy_i);
+
+   reg 		 cross_int, active0, active1;
+
+   assign data0_o = cross_int ? data1_i : data0_i;
+   assign data1_o = cross_int ? data0_i : data1_i;
+
+   assign src0_rdy_o = cross_int ? src1_rdy_i : src0_rdy_i;
+   assign src1_rdy_o = cross_int ? src0_rdy_i : src1_rdy_i;
+
+   assign dst0_rdy_o = cross_int ? dst1_rdy_i : dst0_rdy_i;
+   assign dst1_rdy_o = cross_int ? dst0_rdy_i : dst1_rdy_i;
+   
+   always @(posedge clk)
+     if(reset | clear)
+       active0 <= 0;
+     else if(src0_rdy_i & dst0_rdy_o)
+       active0 <= ~data0_i[33];
+   
+   always @(posedge clk)
+     if(reset | clear)
+       active1 <= 0;
+     else if(src1_rdy_i & dst1_rdy_o)
+       active1 <= ~data1_i[33];
+
+   always @(posedge clk)
+     if(reset | clear)
+       cross_int <= 0;
+     else if(~active0 & ~active1)
+       cross_int <= cross;
+   
+endmodule // crossbar36