aboutsummaryrefslogtreecommitdiffstats
path: root/fpga/usrp2/gpif
diff options
context:
space:
mode:
Diffstat (limited to 'fpga/usrp2/gpif')
-rw-r--r--fpga/usrp2/gpif/Makefile.srcs13
-rw-r--r--fpga/usrp2/gpif/fifo36_to_gpmc16.v54
-rw-r--r--fpga/usrp2/gpif/gpmc16_to_fifo36.v64
-rw-r--r--fpga/usrp2/gpif/packet_reframer.v70
-rw-r--r--fpga/usrp2/gpif/slave_fifo.v274
5 files changed, 475 insertions, 0 deletions
diff --git a/fpga/usrp2/gpif/Makefile.srcs b/fpga/usrp2/gpif/Makefile.srcs
new file mode 100644
index 000000000..7909fb5ff
--- /dev/null
+++ b/fpga/usrp2/gpif/Makefile.srcs
@@ -0,0 +1,13 @@
+#
+# Copyright 2010-2012 Ettus Research LLC
+#
+
+##################################################
+# SERDES Sources
+##################################################
+GPIF_SRCS = $(abspath $(addprefix $(BASE_DIR)/../gpif/, \
+packet_reframer.v \
+slave_fifo.v \
+fifo36_to_gpmc16.v \
+gpmc16_to_fifo36.v \
+))
diff --git a/fpga/usrp2/gpif/fifo36_to_gpmc16.v b/fpga/usrp2/gpif/fifo36_to_gpmc16.v
new file mode 100644
index 000000000..508cd319c
--- /dev/null
+++ b/fpga/usrp2/gpif/fifo36_to_gpmc16.v
@@ -0,0 +1,54 @@
+//
+// Copyright 2012 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 fifo36_to_gpmc16
+#(
+ parameter FIFO_SIZE = 9
+)
+(
+ //input fifo interface
+ input fifo_clk, input fifo_rst,
+ input [35:0] in_data,
+ input in_src_rdy,
+ output in_dst_rdy,
+
+ //output interface
+ input gpif_clk, input gpif_rst,
+ output [15:0] out_data,
+ output valid,
+ input enable,
+ output eof
+);
+
+ wire [35:0] data_int;
+ wire src_rdy_int, dst_rdy_int;
+
+ fifo_2clock_cascade #(.WIDTH(36), .SIZE(FIFO_SIZE)) fifo_2clk
+ (.wclk(fifo_clk), .datain(in_data), .src_rdy_i(in_src_rdy), .dst_rdy_o(in_dst_rdy), .space(),
+ .rclk(gpif_clk), .dataout(data_int), .src_rdy_o(src_rdy_int), .dst_rdy_i(dst_rdy_int), .occupied(),
+ .arst(fifo_rst | gpif_rst));
+
+ wire [18:0] data18_int;
+ fifo36_to_fifo19 #(.LE(1)) f36_to_f19
+ (.clk(gpif_clk), .reset(gpif_rst), .clear(1'b0),
+ .f36_datain(data_int), .f36_src_rdy_i(src_rdy_int), .f36_dst_rdy_o(dst_rdy_int),
+ .f19_dataout(data18_int), .f19_src_rdy_o(valid), .f19_dst_rdy_i(enable) );
+
+ assign out_data = data18_int[15:0];
+ assign eof = data18_int[17];
+
+endmodule //fifo_to_gpmc16
diff --git a/fpga/usrp2/gpif/gpmc16_to_fifo36.v b/fpga/usrp2/gpif/gpmc16_to_fifo36.v
new file mode 100644
index 000000000..933891715
--- /dev/null
+++ b/fpga/usrp2/gpif/gpmc16_to_fifo36.v
@@ -0,0 +1,64 @@
+//
+// Copyright 2012 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 gpmc16_to_fifo36
+#(
+ parameter FIFO_SIZE = 9,
+
+ //not ready until minimum xfers of space available
+ parameter MIN_SPACE16 = 128
+)
+(
+ //input interface
+ input gpif_clk, input gpif_rst,
+ input [15:0] in_data,
+ input valid,
+ output reg ready,
+
+ //output fifo interface
+ input fifo_clk, input fifo_rst,
+ output [35:0] out_data,
+ output out_src_rdy,
+ input out_dst_rdy
+);
+
+ wire [35:0] data_int;
+ wire src_rdy_int, dst_rdy_int;
+ wire [18:0] refr_data;
+ wire refr_src_rdy, refr_dst_rdy;
+
+ wire [15:0] fifo_space;
+
+ always @(posedge gpif_clk)
+ ready <= (fifo_space >= MIN_SPACE16/2);
+
+ packet_reframer packet_reframer
+ (.clk(gpif_clk), .reset(gpif_rst), .clear(1'b0),
+ .data_i(in_data), .src_rdy_i(valid), .dst_rdy_o(),
+ .data_o(refr_data), .src_rdy_o(refr_src_rdy), .dst_rdy_i(refr_dst_rdy));
+
+ fifo19_to_fifo36 #(.LE(1)) f19_to_f36
+ (.clk(gpif_clk), .reset(gpif_rst), .clear(1'b0),
+ .f19_datain(refr_data), .f19_src_rdy_i(refr_src_rdy), .f19_dst_rdy_o(refr_dst_rdy),
+ .f36_dataout(data_int), .f36_src_rdy_o(src_rdy_int), .f36_dst_rdy_i(dst_rdy_int));
+
+ fifo_2clock_cascade #(.WIDTH(36), .SIZE(FIFO_SIZE)) fifo_2clk
+ (.wclk(gpif_clk), .datain(data_int), .src_rdy_i(src_rdy_int), .dst_rdy_o(dst_rdy_int), .space(fifo_space),
+ .rclk(fifo_clk), .dataout(out_data), .src_rdy_o(out_src_rdy), .dst_rdy_i(out_dst_rdy), .occupied(),
+ .arst(fifo_rst | gpif_rst));
+
+endmodule //fifo_to_gpmc16
diff --git a/fpga/usrp2/gpif/packet_reframer.v b/fpga/usrp2/gpif/packet_reframer.v
new file mode 100644
index 000000000..e0ce9e174
--- /dev/null
+++ b/fpga/usrp2/gpif/packet_reframer.v
@@ -0,0 +1,70 @@
+//
+// Copyright 2011-2012 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/>.
+//
+
+
+// Join vita packets longer than one GPIF frame
+
+module packet_reframer
+ (input clk, input reset, input clear,
+ input [15:0] data_i,
+ input src_rdy_i,
+ output dst_rdy_o,
+ output [18:0] data_o,
+ output src_rdy_o,
+ input dst_rdy_i,
+ output reg state,
+ output eof_out,
+ output reg [15:0] length);
+
+ //reg state;
+ //reg [15:0] length;
+
+ localparam RF_IDLE = 0;
+ localparam RF_PKT = 1;
+
+ always @(posedge clk)
+ if(reset | clear)
+ state <= RF_IDLE;
+ else
+ if(src_rdy_i & dst_rdy_i)
+ case(state)
+ RF_IDLE :
+ begin
+ length <= {data_i[14:0],1'b0};
+ state <= RF_PKT;
+ end
+ RF_PKT :
+ begin
+ if(eof_out) state <= RF_IDLE;
+ length <= length - 1;
+ end
+ endcase // case (state)
+
+ assign dst_rdy_o = dst_rdy_i; // this is a little pessimistic but ok
+ assign src_rdy_o = src_rdy_i;
+
+ wire occ_out = 0;
+ assign eof_out = (state == RF_PKT) & (length == 2);
+ wire sof_out = (state == RF_IDLE);
+ assign data_o = {occ_out, eof_out, sof_out, data_i[15:0]};
+
+
+endmodule // packet_reframer
+
+
+
+
diff --git a/fpga/usrp2/gpif/slave_fifo.v b/fpga/usrp2/gpif/slave_fifo.v
new file mode 100644
index 000000000..0f301f8a6
--- /dev/null
+++ b/fpga/usrp2/gpif/slave_fifo.v
@@ -0,0 +1,274 @@
+//
+// Copyright 2011-2012 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/>.
+//
+
+//////////////////////////////////////////////////////////////////////////////////
+
+//this is a FIFO master interface for the FX2 in "slave fifo" mode.
+
+module slave_fifo
+ #(
+ //how many cycles max in a transfer state
+ parameter DATA_XFER_COUNT = 256,
+ parameter CTRL_XFER_COUNT = 32,
+
+ //sizes for fifo36 2 clock cascade fifos
+ parameter DATA_RX_FIFO_SIZE = 9,
+ parameter DATA_TX_FIFO_SIZE = 9,
+ parameter CTRL_RX_FIFO_SIZE = 9,
+ parameter CTRL_TX_FIFO_SIZE = 9
+ )
+ (// GPIF signals
+ input gpif_clk, input gpif_rst,
+ inout [15:0] gpif_d,
+ input [3:0] gpif_ctl,
+ output reg sloe, output reg slrd, output reg slwr, output reg pktend, output reg [1:0] fifoadr,
+
+ // FIFO interface
+ input fifo_clk, input fifo_rst,
+ output [35:0] tx_data, output tx_src_rdy, input tx_dst_rdy,
+ input [35:0] rx_data, input rx_src_rdy, output rx_dst_rdy,
+ output [35:0] ctrl_data, output ctrl_src_rdy, input ctrl_dst_rdy,
+ input [35:0] resp_data, input resp_src_rdy, output resp_dst_rdy,
+
+ output [31:0] debug
+ );
+
+ wire FX2_DE_pre = ~gpif_ctl[0]; //EP2 FX2 FIFO empty (FLAGA)
+ wire FX2_CE_pre = ~gpif_ctl[1]; //EP4 FX2 FIFO empty (FLAGB)
+ wire FX2_DF_pre = ~gpif_ctl[2]; //EP6 FX2 FIFO full (FLAGC)
+ wire FX2_CF_pre = ~gpif_ctl[3]; //EP8 FX2 FIFO full (FLAGD)
+
+ reg FX2_DE, FX2_CE, FX2_DF, FX2_CF;
+ always @(posedge gpif_clk) begin
+ FX2_DE <= FX2_DE_pre; //EP2 FX2 FIFO empty (FLAGA)
+ FX2_CE <= FX2_CE_pre; //EP4 FX2 FIFO empty (FLAGB)
+ FX2_DF <= FX2_DF_pre; //EP6 FX2 FIFO full (FLAGC)
+ FX2_CF <= FX2_CF_pre; //EP8 FX2 FIFO full (FLAGD)
+ end
+
+ wire [15:0] gpif_d_out_ctrl, gpif_d_out_data;
+ reg [15:0] gpif_d_out, gpif_d_in;
+
+ // ////////////////////////////////////////////////////////////////////
+ // GPIF bus master state machine
+
+ wire rx_valid, resp_valid;
+ reg tx_valid, ctrl_valid;
+ wire tx_ready, ctrl_ready;
+ reg rx_enable, resp_enable;
+
+ reg [9:0] transfer_count; //number of lines (a line is 16 bits) in active transfer
+
+ reg [3:0] state; //state machine current state
+ localparam STATE_IDLE = 0;
+ localparam STATE_THINK = 1;
+ localparam STATE_DATA_RX = 2;
+ localparam STATE_DATA_TX = 3;
+ localparam STATE_CTRL_RX = 4;
+ localparam STATE_CTRL_TX = 5;
+ localparam STATE_DATA_TX_SLOE = 6;
+ localparam STATE_CTRL_TX_SLOE = 7;
+ localparam STATE_DATA_RX_ADR = 8;
+ localparam STATE_CTRL_RX_ADR = 9;
+
+ //logs the last bus user for xfer fairness
+ //we only care about data rx vs. tx since ctrl pkts are so short
+ reg last_data_bus_hog;
+ localparam BUS_HOG_RX = 0;
+ localparam BUS_HOG_TX = 1;
+
+ wire resp_eof;
+ reg [1:0] idle_count;
+
+ // //////////////////////////////////////////////////////////////
+ // FX2 slave FIFO bus master state machine
+ //
+ always @(posedge gpif_clk)
+ if(gpif_rst) begin
+ state <= STATE_IDLE;
+ sloe <= 1;
+ slrd <= 1;
+ slwr <= 1;
+ pktend <= 1;
+ rx_enable <= 0;
+ tx_valid <= 0;
+ ctrl_valid <= 0;
+ resp_enable <= 0;
+ idle_count <= 0;
+ end
+ else case (state)
+ STATE_IDLE: begin
+ transfer_count <= 0;
+ sloe <= 1;
+ slrd <= 1;
+ slwr <= 1;
+ pktend <= 1;
+ rx_enable <= 0;
+ tx_valid <= 0;
+ ctrl_valid <= 0;
+ resp_enable <= 0;
+ if (idle_count == 2'b11) state <= STATE_THINK;
+ idle_count <= idle_count + 1;
+ end
+
+ STATE_THINK: begin
+
+ idle_count <= 0;
+
+ //handle transitions to other states
+ if(ctrl_ready & ~FX2_CE) begin //if there's room in the ctrl fifo and the FX2 has ctrl data
+ state <= STATE_CTRL_TX_SLOE;
+ fifoadr <= 2'b01;
+ sloe <= 0;
+ end
+ else if(resp_valid & ~FX2_CF) begin //if the ctrl fifo has data and the FX2 isn't full
+ state <= STATE_CTRL_RX_ADR;
+ fifoadr <= 2'b11;
+ end
+ else if(tx_ready & ~FX2_DE & last_data_bus_hog == BUS_HOG_RX) begin //if there's room in the data fifo and the FX2 has data
+ state <= STATE_DATA_TX_SLOE;
+ last_data_bus_hog <= BUS_HOG_TX;
+ fifoadr <= 2'b00;
+ sloe <= 0;
+ end
+ else if(rx_valid & ~FX2_DF & last_data_bus_hog == BUS_HOG_TX) begin //if the data fifo has data and the FX2 isn't full
+ state <= STATE_DATA_RX_ADR;
+ last_data_bus_hog <= BUS_HOG_RX;
+ fifoadr <= 2'b10;
+ end
+ else if(tx_ready & ~FX2_DE) begin
+ state <= STATE_DATA_TX_SLOE;
+ last_data_bus_hog <= BUS_HOG_TX;
+ fifoadr <= 2'b00;
+ sloe <= 0;
+ end
+ else if(rx_valid & ~FX2_DF) begin
+ state <= STATE_DATA_RX_ADR;
+ last_data_bus_hog <= BUS_HOG_RX;
+ fifoadr <= 2'b10;
+ end
+ end
+
+ STATE_DATA_TX_SLOE: begin //just to assert SLOE one cycle before SLRD
+ state <= STATE_DATA_TX;
+ slrd <= 0;
+ end
+
+ STATE_CTRL_TX_SLOE: begin
+ state <= STATE_CTRL_TX;
+ slrd <= 0;
+ end
+
+ STATE_DATA_RX_ADR: begin //just to assert FIFOADR one cycle before SLWR
+ state <= STATE_DATA_RX;
+ rx_enable <= 1;
+ end
+
+ STATE_CTRL_RX_ADR: begin
+ state <= STATE_CTRL_RX;
+ resp_enable <= 1;
+ end
+
+ STATE_DATA_RX: begin
+ if (FX2_DF_pre || ~rx_valid || transfer_count == DATA_XFER_COUNT-1) begin
+ state <= STATE_IDLE;
+ rx_enable <= 0;
+ end
+ gpif_d_out <= gpif_d_out_data;
+ slwr <= ~rx_valid;
+ transfer_count <= transfer_count + 1;
+ end
+
+ STATE_DATA_TX: begin
+ if (FX2_DE_pre || transfer_count == DATA_XFER_COUNT-1) begin
+ state <= STATE_IDLE;
+ slrd <= 1;
+ end
+ gpif_d_in <= gpif_d;
+ tx_valid <= 1;
+ transfer_count <= transfer_count + 1;
+ end
+
+ STATE_CTRL_RX: begin
+ if (FX2_CF_pre || ~resp_valid || resp_eof || transfer_count == CTRL_XFER_COUNT-1) begin
+ state <= STATE_IDLE;
+ resp_enable <= 0;
+ end
+ pktend <= ~resp_eof;
+ gpif_d_out <= gpif_d_out_ctrl;
+ slwr <= ~resp_valid;
+ transfer_count <= transfer_count + 1;
+ end
+
+ STATE_CTRL_TX: begin
+ if (FX2_CE_pre || transfer_count == CTRL_XFER_COUNT-1) begin
+ state <= STATE_IDLE;
+ slrd <= 1;
+ end
+ gpif_d_in <= gpif_d;
+ ctrl_valid <= 1;
+ transfer_count <= transfer_count + 1;
+ end
+ endcase
+
+ // GPIF output data lines, tristate
+ assign gpif_d = (sloe)? gpif_d_out[15:0] : 16'bz;
+
+ // ////////////////////////////////////////////////////////////////////
+ // TX Data Path
+
+ gpmc16_to_fifo36 #(.FIFO_SIZE(DATA_TX_FIFO_SIZE), .MIN_SPACE16(DATA_XFER_COUNT)) fifo36_to_gpmc16_tx(
+ .gpif_clk(gpif_clk), .gpif_rst(gpif_rst),
+ .in_data(gpif_d_in), .ready(tx_ready), .valid(tx_valid),
+ .fifo_clk(fifo_clk), .fifo_rst(fifo_rst),
+ .out_data(tx_data), .out_src_rdy(tx_src_rdy), .out_dst_rdy(tx_dst_rdy)
+ );
+
+ // ////////////////////////////////////////////
+ // RX Data Path
+
+ fifo36_to_gpmc16 #(.FIFO_SIZE(DATA_RX_FIFO_SIZE)) fifo36_to_gpmc16_rx(
+ .fifo_clk(fifo_clk), .fifo_rst(fifo_rst),
+ .in_data(rx_data), .in_src_rdy(rx_src_rdy), .in_dst_rdy(rx_dst_rdy),
+ .gpif_clk(gpif_clk), .gpif_rst(gpif_rst),
+ .out_data(gpif_d_out_data), .valid(rx_valid), .enable(rx_enable)
+ );
+
+ // ////////////////////////////////////////////////////////////////////
+ // CTRL TX Data Path
+
+ gpmc16_to_fifo36 #(.FIFO_SIZE(CTRL_TX_FIFO_SIZE), .MIN_SPACE16(CTRL_XFER_COUNT)) fifo36_to_gpmc16_ctrl(
+ .gpif_clk(gpif_clk), .gpif_rst(gpif_rst),
+ .in_data(gpif_d_in), .ready(ctrl_ready), .valid(ctrl_valid),
+ .fifo_clk(fifo_clk), .fifo_rst(fifo_rst),
+ .out_data(ctrl_data), .out_src_rdy(ctrl_src_rdy), .out_dst_rdy(ctrl_dst_rdy)
+ );
+
+ // ////////////////////////////////////////////
+ // CTRL RX Data Path
+
+ fifo36_to_gpmc16 #(.FIFO_SIZE(CTRL_RX_FIFO_SIZE)) fifo36_to_gpmc16_resp(
+ .fifo_clk(fifo_clk), .fifo_rst(fifo_rst),
+ .in_data(resp_data), .in_src_rdy(resp_src_rdy), .in_dst_rdy(resp_dst_rdy),
+ .gpif_clk(gpif_clk), .gpif_rst(gpif_rst),
+ .out_data(gpif_d_out_ctrl), .valid(resp_valid), .enable(resp_enable),
+ .eof(resp_eof)
+ );
+
+ assign debug = 0;
+
+endmodule // slave_fifo
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-26 21:57:00 +0000