e100: squashed work on bus implementation on GPMC

1 files changed, 159 insertions, 0 deletions

diff --git a/usrp2/gpmc/gpmc.v b/usrp2/gpmc/gpmc.v
new file mode 100644
index 000000000..a5d4db466
--- /dev/null
+++ b/usrp2/gpmc/gpmc.v
@@ -0,0 +1,159 @@
+//
+// Copyright 2011 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
+
+//////////////////////////////////////////////////////////////////////////////////
+
+module gpmc
+  #(parameter TXFIFOSIZE = 11, 
+    parameter RXFIFOSIZE = 11,
+    parameter ADDR_WIDTH = 10,
+    parameter BUSDEBUG = 1)
+   (// GPMC signals
+    input arst,
+    input EM_CLK, inout [15:0] EM_D, input [ADDR_WIDTH:1] EM_A, input [1:0] EM_NBE,
+    input EM_WAIT0, input EM_NCS4, input EM_NCS6, input EM_NWE, input EM_NOE,
+    
+    // GPIOs for FIFO signalling
+    output rx_have_data, output tx_have_space,
+    
+    // Wishbone signals
+    input wb_clk, input wb_rst,
+    output [ADDR_WIDTH:0] wb_adr_o, output [15:0] wb_dat_mosi, input [15:0] wb_dat_miso,
+    output [1:0] wb_sel_o, output wb_cyc_o, output wb_stb_o, output wb_we_o, input wb_ack_i,
+    
+    // FIFO interface
+    input fifo_clk, input fifo_rst, input clear_tx, input clear_rx,
+    output [35:0] tx_data_o, output tx_src_rdy_o, input tx_dst_rdy_i,
+    input [35:0] rx_data_i, input rx_src_rdy_i, output rx_dst_rdy_o,
+
+    output tx_underrun, output rx_overrun,
+    input [7:0] test_rate, input [3:0] test_ctrl,
+    output [31:0] debug
+    );
+
+   wire 	  EM_output_enable = (~EM_NOE & (~EM_NCS4 | ~EM_NCS6));
+   wire [15:0] 	  EM_D_fifo;
+   wire [15:0] 	  EM_D_wb;
+
+   assign EM_D = ~EM_output_enable ? 16'bz : ~EM_NCS4 ? EM_D_fifo : EM_D_wb;
+
+   // CS4 is RAM_2PORT for DATA PATH (high-speed data)
+   //    Writes go into one RAM, reads come from the other
+   // CS6 is for CONTROL PATH (wishbone)
+
+   // ////////////////////////////////////////////
+   // TX Data Path
+
+   wire [17:0] 	  tx18_data;
+   wire 	  tx18_src_rdy, tx18_dst_rdy;
+   wire [35:0] 	  tx_data, txb_data;
+   wire 	  tx_src_rdy, tx_dst_rdy;
+   wire 	  txb_src_rdy, txb_dst_rdy;
+
+   gpmc_to_fifo #(.ADDR_WIDTH(ADDR_WIDTH)) gpmc_to_fifo
+     (.EM_D(EM_D), .EM_A(EM_A), .EM_CLK(EM_CLK), .EM_WE(~EM_NCS4 & ~EM_NWE),
+      .clk(fifo_clk), .reset(fifo_rst), .clear(clear_tx), .arst(fifo_rst | clear_tx | arst),
+      .data_o(tx18_data), .src_rdy_o(tx18_src_rdy), .dst_rdy_i(tx18_dst_rdy),
+      .have_space(tx_have_space));
+
+   fifo19_to_fifo36 #(.LE(1)) f19_to_f36   // Little endian because ARM is LE
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_tx),
+      .f19_datain({1'b0,tx18_data}), .f19_src_rdy_i(tx18_src_rdy), .f19_dst_rdy_o(tx18_dst_rdy),
+      .f36_dataout(txb_data), .f36_src_rdy_o(txb_src_rdy), .f36_dst_rdy_i(txb_dst_rdy));
+
+   fifo_cascade #(.WIDTH(36), .SIZE(TXFIFOSIZE)) tx_buffering(
+        .clk(fifo_clk), .reset(fifo_rst), .clear(clear_tx),
+        .datain(txb_data), .src_rdy_i(txb_src_rdy), .dst_rdy_o(txb_dst_rdy),
+        .dataout(tx_data), .src_rdy_o(tx_src_rdy), .dst_rdy_i(tx_dst_rdy)
+   );
+
+   // ////////////////////////////////////////////
+   // RX Data Path
+   
+   wire [17:0] 	  rx18_data;
+   wire 	  rx18_src_rdy, rx18_dst_rdy;
+   wire [35:0] 	  rx_data, rxb_data;
+   wire 	  rx_src_rdy, rx_dst_rdy;
+   wire 	  rxb_src_rdy, rxb_dst_rdy;
+   wire 	  dummy;
+
+   fifo_cascade #(.WIDTH(36), .SIZE(RXFIFOSIZE)) rx_buffering(
+        .clk(fifo_clk), .reset(fifo_rst), .clear(clear_rx),
+        .datain(rx_data), .src_rdy_i(rx_src_rdy), .dst_rdy_o(rx_dst_rdy),
+        .dataout(rxb_data), .src_rdy_o(rxb_src_rdy), .dst_rdy_i(rxb_dst_rdy)
+   );
+
+   fifo36_to_fifo19 #(.LE(1)) f36_to_f19   // Little endian because ARM is LE
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_rx),
+      .f36_datain(rxb_data), .f36_src_rdy_i(rxb_src_rdy), .f36_dst_rdy_o(rxb_dst_rdy),
+      .f19_dataout({dummy,rx18_data}), .f19_src_rdy_o(rx18_src_rdy), .f19_dst_rdy_i(rx18_dst_rdy) );
+
+   fifo_to_gpmc #(.ADDR_WIDTH(ADDR_WIDTH)) fifo_to_gpmc
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_rx), .arst(fifo_rst | clear_rx | arst),
+      .data_i(rx18_data), .src_rdy_i(rx18_src_rdy), .dst_rdy_o(rx18_dst_rdy),
+      .EM_D(EM_D_fifo), .EM_A(EM_A), .EM_CLK(EM_CLK), .EM_OE(~EM_NCS4 & ~EM_NOE),
+      .data_available(rx_have_data));
+
+   // ////////////////////////////////////////////
+   // Control path on CS6
+   
+   gpmc_wb gpmc_wb
+     (.EM_CLK(EM_CLK), .EM_D_in(EM_D), .EM_D_out(EM_D_wb), .EM_A(EM_A), .EM_NBE(EM_NBE),
+      .EM_WE(~EM_NCS6 & ~EM_NWE), .EM_OE(~EM_NCS6 & ~EM_NOE),
+      .wb_clk(wb_clk), .wb_rst(wb_rst),
+      .wb_adr_o(wb_adr_o), .wb_dat_mosi(wb_dat_mosi), .wb_dat_miso(wb_dat_miso),
+      .wb_sel_o(wb_sel_o), .wb_cyc_o(wb_cyc_o), .wb_stb_o(wb_stb_o), .wb_we_o(wb_we_o),
+      .wb_ack_i(wb_ack_i) );
+
+   // ////////////////////////////////////////////
+   // Test support, traffic generator, loopback, etc.
+
+   // RX side muxes test data into the same stream
+   wire [35:0] loopbackrx_data, testrx_data;
+   wire [35:0] loopbacktx_data, testtx_data;
+   wire        loopbackrx_src_rdy, loopbackrx_dst_rdy;
+   wire        loopbacktx_src_rdy, loopbacktx_dst_rdy;
+   wire        sel_testtx = test_ctrl[0];
+
+   fifo36_mux rx_test_mux_lvl_2
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_rx),
+      .data0_i(loopbackrx_data), .src0_rdy_i(loopbackrx_src_rdy), .dst0_rdy_o(loopbackrx_dst_rdy),
+      .data1_i(rx_data_i), .src1_rdy_i(rx_src_rdy_i), .dst1_rdy_o(rx_dst_rdy_o),
+      .data_o(rx_data), .src_rdy_o(rx_src_rdy), .dst_rdy_i(rx_dst_rdy));
+
+   fifo_short #(.WIDTH(36)) loopback_fifo
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_tx | clear_rx),
+      .datain(loopbacktx_data), .src_rdy_i(loopbacktx_src_rdy), .dst_rdy_o(loopbacktx_dst_rdy),
+      .dataout(loopbackrx_data), .src_rdy_o(loopbackrx_src_rdy), .dst_rdy_i(loopbackrx_dst_rdy));
+
+   // Crossbar used as a demux for switching TX stream to main DSP or to test logic
+   crossbar36 tx_crossbar_lvl_1
+     (.clk(fifo_clk), .reset(fifo_rst), .clear(clear_tx),
+      .cross(sel_testtx),
+      .data0_i(tx_data), .src0_rdy_i(tx_src_rdy), .dst0_rdy_o(tx_dst_rdy),
+      .data1_i(tx_data), .src1_rdy_i(1'b0), .dst1_rdy_o(),  // No 2nd input
+      .data0_o(tx_data_o), .src0_rdy_o(tx_src_rdy_o), .dst0_rdy_i(tx_dst_rdy_i),
+      .data1_o(loopbacktx_data), .src1_rdy_o(loopbacktx_src_rdy), .dst1_rdy_i(loopbacktx_dst_rdy) );
+
+   assign debug = {
+        EM_D, //16
+        EM_A, //10
+        EM_CLK, EM_NCS4, EM_NWE, EM_NOE, //4
+        EM_NCS6, wb_ack_i
+   };
+
+endmodule // gpmc