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Diffstat (limited to 'fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v')
-rw-r--r-- | fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v b/fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v new file mode 100644 index 000000000..1f168420d --- /dev/null +++ b/fpga/usrp3/lib/fifo/axi_fifo32_to_fifo64.v @@ -0,0 +1,44 @@ +// +// Copyright 2014 Ettus Research LLC +// Copyright 2018 Ettus Research, a National Instruments Company +// +// SPDX-License-Identifier: LGPL-3.0-or-later +// + +module axi_fifo32_to_fifo64 + (input clk, input reset, input clear, + input [31:0] i_tdata, input [1:0] i_tuser, input i_tlast, input i_tvalid, output i_tready, + output [63:0] o_tdata, output [2:0] o_tuser, output o_tlast, output o_tvalid, input o_tready + ); + + reg [31:0] holding; + + reg state; + + always @(posedge clk) + if(reset | clear) + state <= 0; + else + if(i_tvalid & i_tready) + case(state) + 0 : if(~i_tlast) state <= 1'b1; + 1 : state <= 1'b0; + default : state <= 1'b0; + endcase // case (state) + + always @(posedge clk) + if(i_tvalid & i_tready) + holding <= i_tdata; + + assign i_tready = (state == 0 && !i_tlast)? 1'b1 : o_tready; + assign o_tvalid = (state == 0 && !i_tlast)? 1'b0 : i_tvalid; + + assign o_tdata = (state == 0) ? {i_tdata, 32'h0} : { holding, i_tdata }; + assign o_tlast = i_tlast; + + wire [2:0] occ_in = (i_tuser == 0) ? 3'd4 : {1'b0, i_tuser}; + wire [2:0] occ_out = (state == 0) ? occ_in : (occ_in + 3'd4); + + assign o_tuser = ~o_tlast ? 3'd0 : occ_out; + +endmodule // axi_fifo32_to_fifo64 |