added little endian capability for gpmc to fifo and fifo to gpmc, since ARM is LE.

4 files changed, 51 insertions, 41 deletions

diff --git a/usrp2/control_lib/newfifo/fifo19_to_fifo36.v b/usrp2/control_lib/newfifo/fifo19_to_fifo36.v
index 5f9aeff9b..0e6bcea68 100644
--- a/usrp2/control_lib/newfifo/fifo19_to_fifo36.v
+++ b/usrp2/control_lib/newfifo/fifo19_to_fifo36.v
@@ -1,26 +1,31 @@
 
+// Parameter LE tells us if we are little-endian.  
+// Little-endian means send lower 16 bits first.
+// Default is big endian (network order), send upper bits first.
+
 module fifo19_to_fifo36
-  (input clk, input reset, input clear,
-   input [18:0] f19_datain,
-   input f19_src_rdy_i,
-   output f19_dst_rdy_o,
+  #(parameter LE=0)
+   (input clk, input reset, input clear,
+    input [18:0] f19_datain,
+    input f19_src_rdy_i,
+    output f19_dst_rdy_o,
 
-   output [35:0] f36_dataout,
-   output f36_src_rdy_o,
-   input f36_dst_rdy_i,
-   output [31:0] debug
-   );
+    output [35:0] f36_dataout,
+    output f36_src_rdy_o,
+    input f36_dst_rdy_i,
+    output [31:0] debug
+    );
 
-   reg 	 f36_sof, f36_eof, f36_occ;
+   reg 		  f36_sof, f36_eof, f36_occ;
    
-   reg [1:0] state;
-   reg [15:0] dat0, dat1;
+   reg [1:0] 	  state;
+   reg [15:0] 	  dat0, dat1;
 
-   wire f19_sof  = f19_datain[16];
-   wire f19_eof  = f19_datain[17];
-   wire f19_occ  = f19_datain[18];
+   wire 	  f19_sof  = f19_datain[16];
+   wire 	  f19_eof  = f19_datain[17];
+   wire 	  f19_occ  = f19_datain[18];
 
-   wire xfer_out = f36_src_rdy_o & f36_dst_rdy_i;
+   wire 	  xfer_out = f36_src_rdy_o & f36_dst_rdy_i;
 
    always @(posedge clk)
      if(f19_src_rdy_i & ((state==0)|xfer_out))
@@ -68,7 +73,8 @@ module fifo19_to_fifo36
        dat0 		   <= f19_datain;
    
    assign    f19_dst_rdy_o  = xfer_out | (state != 2);
-   assign    f36_dataout    = {f36_occ,f36_eof,f36_sof,dat0,dat1};
+   assign    f36_dataout    = LE ? {f36_occ,f36_eof,f36_sof,dat1,dat0} :
+			      {f36_occ,f36_eof,f36_sof,dat0,dat1};
    assign    f36_src_rdy_o  = (state == 2);
 
    assign    debug = state;
diff --git a/usrp2/control_lib/newfifo/fifo36_to_fifo19.v b/usrp2/control_lib/newfifo/fifo36_to_fifo19.v
index de249aaeb..517a2a476 100644
--- a/usrp2/control_lib/newfifo/fifo36_to_fifo19.v
+++ b/usrp2/control_lib/newfifo/fifo36_to_fifo19.v
@@ -1,33 +1,38 @@
 
-module fifo36_to_fifo19
-  (input clk, input reset, input clear,
-   input [35:0] f36_datain,
-   input f36_src_rdy_i,
-   output f36_dst_rdy_o,
-   
-   output [18:0] f19_dataout,
-   output f19_src_rdy_o,
-   input f19_dst_rdy_i );
+// Parameter LE tells us if we are little-endian.  
+// Little-endian means send lower 16 bits first.
+// Default is big endian (network order), send upper bits first.
 
+module fifo36_to_fifo19
+  #(parameter LE=0)
+   (input clk, input reset, input clear,
+    input [35:0] f36_datain,
+    input f36_src_rdy_i,
+    output f36_dst_rdy_o,
+    
+    output [18:0] f19_dataout,
+    output f19_src_rdy_o,
+    input f19_dst_rdy_i );
+   
    wire   f36_sof  = f36_datain[32];
    wire   f36_eof  = f36_datain[33];
    wire   f36_occ  = f36_datain[35:34];
-
-   reg phase;
-
-   wire half_line 	   = f36_eof & ((f36_occ==1)|(f36_occ==2));
    
-   assign f19_dataout[15:0] = phase ? f36_datain[15:0] : f36_datain[31:16];
+   reg 	  phase;
+   
+   wire   half_line 	   = f36_eof & ((f36_occ==1)|(f36_occ==2));
+   
+   assign f19_dataout[15:0] = (LE ^ phase) ? f36_datain[15:0] : f36_datain[31:16];
    assign f19_dataout[16]  = phase ? 0 : f36_sof;
    assign f19_dataout[17]  = phase ? f36_eof : half_line;
    assign f19_dataout[18]  = f19_dataout[17] & ((f36_occ==1)|(f36_occ==3));
    
    assign f19_src_rdy_o    = f36_src_rdy_i;
    assign f36_dst_rdy_o    = (phase | half_line) & f19_dst_rdy_i;
-	
-   wire f19_xfer 	   = f19_src_rdy_o & f19_dst_rdy_i;
-   wire f36_xfer 	   = f36_src_rdy_i & f36_dst_rdy_o;
-
+   
+   wire   f19_xfer 	   = f19_src_rdy_o & f19_dst_rdy_i;
+   wire   f36_xfer 	   = f36_src_rdy_i & f36_dst_rdy_o;
+   
    always @(posedge clk)
      if(reset)
        phase 		  <= 0;
@@ -36,6 +41,5 @@ module fifo36_to_fifo19
      else if(f19_xfer)
        phase 		  <= 1;
    
-       
+   
 endmodule // fifo36_to_fifo19
-
diff --git a/usrp2/gpmc/gpmc_async.v b/usrp2/gpmc/gpmc_async.v
index f42b835ed..1050cef7d 100644
--- a/usrp2/gpmc/gpmc_async.v
+++ b/usrp2/gpmc/gpmc_async.v
@@ -64,7 +64,7 @@ module gpmc_async
       .datain(tx18_data), .src_rdy_i(tx18_src_rdy), .dst_rdy_o(tx18_dst_rdy), .space(tx_fifo_space),
       .dataout(tx18b_data), .src_rdy_o(tx18b_src_rdy), .dst_rdy_i(tx18b_dst_rdy), .occupied());
 
-   fifo19_to_fifo36 f19_to_f36
+   fifo19_to_fifo36 #(.LE(1)) f19_to_f36   // Little endian because ARM is LE
      (.clk(fifo_clk), .reset(fifo_rst), .clear(0),
       .f19_datain({1'b0,tx18b_data}), .f19_src_rdy_i(tx18b_src_rdy), .f19_dst_rdy_o(tx18b_dst_rdy),
       .f36_dataout(tx36_data), .f36_src_rdy_o(tx36_src_rdy), .f36_dst_rdy_i(tx36_dst_rdy));
@@ -89,7 +89,7 @@ module gpmc_async
       .datain(rx_data_i), .src_rdy_i(rx_src_rdy_i), .dst_rdy_o(rx_dst_rdy_o),
       .dataout(rx36_data), .src_rdy_o(rx36_src_rdy), .dst_rdy_i(rx36_dst_rdy));
 
-   fifo36_to_fifo19 f36_to_f19
+   fifo36_to_fifo19 #(.LE(1)) f36_to_f19   // Little endian because ARM is LE
      (.clk(fifo_clk), .reset(fifo_rst), .clear(0),
       .f36_datain(rx36_data), .f36_src_rdy_i(rx36_src_rdy), .f36_dst_rdy_o(rx36_dst_rdy),
       .f19_dataout({dummy,rx18_data}), .f19_src_rdy_o(rx18_src_rdy), .f19_dst_rdy_i(rx18_dst_rdy) );
diff --git a/usrp2/gpmc/gpmc_sync.v b/usrp2/gpmc/gpmc_sync.v
index bac489ca0..61c54a793 100644
--- a/usrp2/gpmc/gpmc_sync.v
+++ b/usrp2/gpmc/gpmc_sync.v
@@ -57,7 +57,7 @@ module gpmc_sync
       .rclk(fifo_clk), .dataout(tx18b_data), 
       .src_rdy_o(tx18b_src_rdy), .dst_rdy_i(tx18b_dst_rdy), .occupied(), .arst(arst));
 
-   fifo19_to_fifo36 f19_to_f36
+   fifo19_to_fifo36 #(.LE(1)) f19_to_f36   // Little endian because ARM is LE
      (.clk(fifo_clk), .reset(fifo_rst), .clear(0),
       .f19_datain({1'b0,tx18b_data}), .f19_src_rdy_i(tx18b_src_rdy), .f19_dst_rdy_o(tx18b_dst_rdy),
       .f36_dataout(tx_data_o), .f36_src_rdy_o(tx_src_rdy_o), .f36_dst_rdy_i(tx_dst_rdy_i));
@@ -70,7 +70,7 @@ module gpmc_sync
    wire [15:0] 	rx_fifo_space, rx_frame_len;
    wire 	dummy;
    
-   fifo36_to_fifo19 f36_to_f19
+   fifo36_to_fifo19 #(.LE(1)) f36_to_f19   // Little endian because ARM is LE
      (.clk(fifo_clk), .reset(fifo_rst), .clear(0),
       .f36_datain(rx_data_i), .f36_src_rdy_i(rx_src_rdy_i), .f36_dst_rdy_o(rx_dst_rdy_o),
       .f19_dataout({dummy,rx18_data}), .f19_src_rdy_o(rx18_src_rdy), .f19_dst_rdy_i(rx18_dst_rdy) );