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authorMatt Ettus <matt@ettus.com>2011-03-07 18:22:55 -0800
committerMatt Ettus <matt@ettus.com>2011-03-07 18:22:55 -0800
commitbb9d849d40494c745e7384734b999b78ef219b9b (patch)
tree630d0d8ecb57613fe2e99a328986e1ff3aea028a /usrp2/fifo
parent88b6ef9a187a34d6fb512e9c83c9727bc3c0fa78 (diff)
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first cut at 36:72 and 72:36 for extra wide fifos. untested
Diffstat (limited to 'usrp2/fifo')
-rw-r--r--usrp2/fifo/fifo36_to_fifo72.v125
-rw-r--r--usrp2/fifo/fifo72_to_fifo36.v63
2 files changed, 188 insertions, 0 deletions
diff --git a/usrp2/fifo/fifo36_to_fifo72.v b/usrp2/fifo/fifo36_to_fifo72.v
new file mode 100644
index 000000000..038eda9e9
--- /dev/null
+++ b/usrp2/fifo/fifo36_to_fifo72.v
@@ -0,0 +1,125 @@
+
+// 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_fifo72
+ #(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 [71:0] f72_dataout,
+ output f72_src_rdy_o,
+ input f72_dst_rdy_i,
+ output [31:0] debug
+ );
+
+ // Shortfifo on input to guarantee no deadlock
+ wire [35:0] f36_data_int;
+ wire f36_src_rdy_int, f36_dst_rdy_int;
+
+ fifo_short #(.WIDTH(36)) head_fifo
+ (.clk(clk),.reset(reset),.clear(clear),
+ .datain(f36_datain), .src_rdy_i(f36_src_rdy_i), .dst_rdy_o(f36_dst_rdy_o),
+ .dataout(f36_data_int), .src_rdy_o(f36_src_rdy_int), .dst_rdy_i(f36_dst_rdy_int),
+ .space(),.occupied() );
+
+ // Actual f36 to f72 which could deadlock if not connected to shortfifos
+ reg f72_sof_int, f72_eof_int;
+ reg [2:0] f72_occ_int;
+ wire [71:0] f72_data_int;
+ wire f72_src_rdy_int, f72_dst_rdy_int;
+
+ reg [1:0] state;
+ reg [31:0] dat0, dat1;
+
+ wire f36_sof_int = f36_data_int[32];
+ wire f36_eof_int = f36_data_int[33];
+ wire [1:0] f36_occ_int = f36_data_int[35:34];
+
+ wire xfer_out = f72_src_rdy_int & f72_dst_rdy_int;
+
+ always @(posedge clk)
+ if(f36_src_rdy_int & ((state==0)|xfer_out))
+ f72_sof_int <= f36_sof_int;
+
+ always @(posedge clk)
+ if(f36_src_rdy_int & ((state != 2)|xfer_out))
+ f72_eof_int <= f36_eof_int;
+
+ always @(posedge clk)
+ if(reset)
+ begin
+ state <= 0;
+ f72_occ_int <= 0;
+ end
+ else
+ if(f36_src_rdy_int)
+ case(state)
+ 0 :
+ begin
+ dat0 <= f36_data_int;
+ if(f36_eof_int)
+ begin
+ state <= 2;
+ case (f36_occ_int)
+ 0 : f72_occ_int <= 3'd4;
+ 1 : f72_occ_int <= 3'd1;
+ 2 : f72_occ_int <= 3'd2;
+ 3 : f72_occ_int <= 3'd3;
+ endcase // case (f36_occ_int)
+ end
+ else
+ state <= 1;
+ end
+ 1 :
+ begin
+ dat1 <= f36_data_int;
+ state <= 2;
+ if(f36_eof_int)
+ case (f36_occ_int)
+ 0 : f72_occ_int <= 3'd0;
+ 1 : f72_occ_int <= 3'd5;
+ 2 : f72_occ_int <= 3'd6;
+ 3 : f72_occ_int <= 3'd7;
+ endcase // case (f36_occ_int)
+ end
+ 2 :
+ if(xfer_out)
+ begin
+ dat0 <= f36_data_int;
+ if(f36_eof_int) // remain in state 2 if we are at eof
+ case (f36_occ_int)
+ 0 : f72_occ_int <= 3'd4;
+ 1 : f72_occ_int <= 3'd1;
+ 2 : f72_occ_int <= 3'd2;
+ 3 : f72_occ_int <= 3'd3;
+ endcase // case (f36_occ_int)
+ else
+ state <= 1;
+ end
+ endcase // case(state)
+ else
+ if(xfer_out)
+ begin
+ state <= 0;
+ f72_occ_int <= 0;
+ end
+
+ assign f36_dst_rdy_int = xfer_out | (state != 2);
+ assign f72_data_int = LE ? {3'b000,f72_occ_int[2:0],f72_eof_int,f72_sof_int,dat1,dat0} :
+ {3'b000,f72_occ_int[2:0],f72_eof_int,f72_sof_int,dat0,dat1};
+ assign f72_src_rdy_int = (state == 2);
+
+ assign debug = state;
+
+ // Shortfifo on output to guarantee no deadlock
+ fifo_short #(.WIDTH(72)) tail_fifo
+ (.clk(clk),.reset(reset),.clear(clear),
+ .datain(f72_data_int), .src_rdy_i(f72_src_rdy_int), .dst_rdy_o(f72_dst_rdy_int),
+ .dataout(f72_dataout), .src_rdy_o(f72_src_rdy_o), .dst_rdy_i(f72_dst_rdy_i),
+ .space(),.occupied() );
+
+endmodule // fifo36_to_fifo72
diff --git a/usrp2/fifo/fifo72_to_fifo36.v b/usrp2/fifo/fifo72_to_fifo36.v
new file mode 100644
index 000000000..1b3bc3ab7
--- /dev/null
+++ b/usrp2/fifo/fifo72_to_fifo36.v
@@ -0,0 +1,63 @@
+
+// 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 fifo72_to_fifo36
+ #(parameter LE=0)
+ (input clk, input reset, input clear,
+ input [71:0] f72_datain,
+ input f72_src_rdy_i,
+ output f72_dst_rdy_o,
+
+ output [35:0] f36_dataout,
+ output f36_src_rdy_o,
+ input f36_dst_rdy_i );
+
+ wire [35:0] f36_data_int;
+ wire f36_src_rdy_int, f36_dst_rdy_int;
+ wire [71:0] f72_data_int;
+ wire f72_src_rdy_int, f72_dst_rdy_int;
+
+ // Shortfifo on input to guarantee no deadlock
+ fifo_short #(.WIDTH(72)) head_fifo
+ (.clk(clk),.reset(reset),.clear(clear),
+ .datain(f72_datain), .src_rdy_i(f72_src_rdy_i), .dst_rdy_o(f72_dst_rdy_o),
+ .dataout(f72_data_int), .src_rdy_o(f72_src_rdy_int), .dst_rdy_i(f72_dst_rdy_int),
+ .space(),.occupied() );
+
+ // Main fifo72_to_fifo36, needs shortfifos to guarantee no deadlock
+ wire [2:0] f72_occ_int = f72_data_int[68:66];
+ wire f72_sof_int = f72_data_int[64];
+ wire f72_eof_int = f72_data_int[65];
+
+ reg phase;
+ wire half_line = f72_eof_int & ( (f72_occ_int==1)|(f72_occ_int==2)|(f72_occ_int==3)|(f72_occ_int==4) );
+
+ assign f36_data_int[31:0] = (LE ^ phase) ? f72_data_int[31:0] : f72_data_int[63:32];
+ assign f36_data_int[32] = phase ? 0 : f72_sof_int;
+ assign f36_data_int[33] = phase ? f72_eof_int : half_line;
+ assign f36_data_int[35:34] = f36_data_int[33] ? f72_occ_int[1:0] : 2'b00;
+
+ assign f36_src_rdy_int = f72_src_rdy_int;
+ assign f72_dst_rdy_int = (phase | half_line) & f36_dst_rdy_int;
+
+ wire f36_xfer = f36_src_rdy_int & f36_dst_rdy_int;
+ wire f72_xfer = f72_src_rdy_int & f72_dst_rdy_int;
+
+ always @(posedge clk)
+ if(reset)
+ phase <= 0;
+ else if(f72_xfer)
+ phase <= 0;
+ else if(f36_xfer)
+ phase <= 1;
+
+ // Shortfifo on output to guarantee no deadlock
+ fifo_short #(.WIDTH(36)) tail_fifo
+ (.clk(clk),.reset(reset),.clear(clear),
+ .datain(f36_data_int), .src_rdy_i(f36_src_rdy_int), .dst_rdy_o(f36_dst_rdy_int),
+ .dataout(f36_dataout), .src_rdy_o(f36_src_rdy_o), .dst_rdy_i(f36_dst_rdy_i),
+ .space(),.occupied() );
+
+endmodule // fifo72_to_fifo36