Merge branch 'udp'

1 files changed, 47 insertions, 0 deletions

diff --git a/fpga/usrp2/control_lib/system_control.v b/fpga/usrp2/control_lib/system_control.v
new file mode 100644
index 000000000..5d89f13db
--- /dev/null
+++ b/fpga/usrp2/control_lib/system_control.v
@@ -0,0 +1,47 @@
+// System bootup order:
+//    0 - Internal POR to reset this block.  Maybe control it from CPLD in the future?
+//    1 - Everything in reset
+//    2 - Take RAM Loader out of reset
+//    3 - When RAM Loader done, take processor and wishbone out of reset
+
+module system_control 
+  (input wb_clk_i,
+   output reg ram_loader_rst_o,
+   output reg wb_rst_o,
+   input ram_loader_done_i
+   );
+
+   reg 		POR = 1'b1;
+   reg [3:0] 	POR_ctr;
+
+   initial POR_ctr = 4'd0;
+   always @(posedge wb_clk_i)
+     if(POR_ctr == 4'd15)
+       POR <= 1'b0;
+     else
+       POR_ctr <= POR_ctr + 4'd1;
+   
+   always @(posedge POR or posedge wb_clk_i)
+     if(POR)
+       ram_loader_rst_o <= 1'b1;
+     else
+       ram_loader_rst_o <= #1 1'b0;
+
+   // Main system reset
+   reg 		delayed_rst;
+   
+   always @(posedge POR or posedge wb_clk_i)
+     if(POR)
+       begin
+	  wb_rst_o <= 1'b1;
+	  delayed_rst <= 1'b1;
+       end
+     else if(ram_loader_done_i)
+       begin
+	  delayed_rst <= 1'b0;
+	  wb_rst_o <= delayed_rst;
+       end
+
+endmodule // system_control
+
+