fpga: lib: Fix comments and indentation in axi_fifo_short.v
Original-commit: da3af4e6e86809038872a61696f3d1bac2e8583c
This commit is contained in:
committed by
Aaron Rossetto
parent
3bbc81bb44
commit
7834312db6
+91
-102
@@ -1,113 +1,102 @@
|
||||
//
|
||||
// Copyright 2012 Ettus Research LLC
|
||||
// Copyright 2018 Ettus Research, a National Instruments Company
|
||||
// Copyright 2020 Ettus Research, a National Instruments Brand
|
||||
//
|
||||
// SPDX-License-Identifier: LGPL-3.0-or-later
|
||||
//
|
||||
|
||||
|
||||
// Description: 32 word FIFO with AXI4-Stream interface.
|
||||
//
|
||||
// 32 word FIFO with AXI4-STREAM interface.
|
||||
//
|
||||
// NOTE: This module uses the SRLC32E primitive explicitly and as such
|
||||
// can only be used with Xilinx technology of the VIRTEX-6/SPARTAN-6/SIERIES-7 or newer.
|
||||
// NOTE: This module uses the SRLC32E primitive explicitly and as such can
|
||||
// only be used with Xilinx technology.
|
||||
//
|
||||
|
||||
module axi_fifo_short
|
||||
#(parameter WIDTH=32)
|
||||
(
|
||||
input clk,
|
||||
input reset,
|
||||
input clear,
|
||||
input [WIDTH-1:0] i_tdata,
|
||||
input i_tvalid,
|
||||
output i_tready,
|
||||
output [WIDTH-1:0] o_tdata,
|
||||
output o_tvalid,
|
||||
input o_tready,
|
||||
module axi_fifo_short #(
|
||||
parameter WIDTH = 32
|
||||
) (
|
||||
input clk,
|
||||
input reset,
|
||||
input clear,
|
||||
input [WIDTH-1:0] i_tdata,
|
||||
input i_tvalid,
|
||||
output i_tready,
|
||||
output [WIDTH-1:0] o_tdata,
|
||||
output o_tvalid,
|
||||
input o_tready,
|
||||
|
||||
output reg [5:0] space,
|
||||
output reg [5:0] occupied
|
||||
);
|
||||
|
||||
reg full = 1'b0, empty = 1'b1;
|
||||
wire write = i_tvalid & i_tready;
|
||||
wire read = o_tready & o_tvalid;
|
||||
|
||||
assign i_tready = ~full;
|
||||
assign o_tvalid = ~empty;
|
||||
|
||||
reg [4:0] a;
|
||||
genvar i;
|
||||
|
||||
generate
|
||||
for (i=0;i<WIDTH;i=i+1) begin : gen_srlc32e
|
||||
SRLC32E srlc32e(
|
||||
.Q(o_tdata[i]), .Q31(),
|
||||
.A(a),
|
||||
.CE(write),.CLK(clk),.D(i_tdata[i])
|
||||
);
|
||||
end
|
||||
endgenerate
|
||||
|
||||
always @(posedge clk) begin
|
||||
if(reset) begin
|
||||
a <= 0;
|
||||
empty <= 1;
|
||||
full <= 0;
|
||||
end
|
||||
else if(clear) begin
|
||||
a <= 0;
|
||||
empty <= 1;
|
||||
full<= 0;
|
||||
end
|
||||
else if(read & ~write) begin
|
||||
full <= 0;
|
||||
if(a==0)
|
||||
empty <= 1;
|
||||
else
|
||||
a <= a - 1;
|
||||
end
|
||||
else if(write & ~read) begin
|
||||
empty <= 0;
|
||||
if(~empty)
|
||||
a <= a + 1;
|
||||
if(a == 30)
|
||||
full <= 1;
|
||||
end
|
||||
end
|
||||
|
||||
// NOTE: Will fail if you write into a full FIFO or read from an empty one
|
||||
|
||||
always @(posedge clk) begin
|
||||
if(reset)
|
||||
space <= 6'd32;
|
||||
else if(clear)
|
||||
space <= 6'd32;
|
||||
else if(read & ~write)
|
||||
space <= space + 6'd1;
|
||||
else if(write & ~read)
|
||||
space <= space - 6'd1;
|
||||
end
|
||||
|
||||
always @(posedge clk) begin
|
||||
if(reset)
|
||||
occupied <= 6'd0;
|
||||
else if(clear)
|
||||
occupied <= 6'd0;
|
||||
else if(read & ~write)
|
||||
occupied <= occupied - 6'd1;
|
||||
else if(write & ~read)
|
||||
occupied <= occupied + 6'd1;
|
||||
end
|
||||
|
||||
output reg [5:0] space,
|
||||
output reg [5:0] occupied
|
||||
);
|
||||
|
||||
reg full = 1'b0, empty = 1'b1;
|
||||
wire write = i_tvalid & i_tready;
|
||||
wire read = o_tready & o_tvalid;
|
||||
|
||||
assign i_tready = ~full;
|
||||
assign o_tvalid = ~empty;
|
||||
|
||||
reg [4:0] a;
|
||||
genvar i;
|
||||
|
||||
generate
|
||||
for (i=0;i<WIDTH;i=i+1)
|
||||
begin : gen_srlc32e
|
||||
SRLC32E
|
||||
srlc32e(.Q(o_tdata[i]), .Q31(),
|
||||
.A(a), //.A0(a[0]),.A1(a[1]),.A2(a[2]),.A3(a[3]),.A4(a[4]),
|
||||
.CE(write),.CLK(clk),.D(i_tdata[i]));
|
||||
end
|
||||
endgenerate
|
||||
|
||||
always @(posedge clk)
|
||||
if(reset)
|
||||
begin
|
||||
a <= 0;
|
||||
empty <= 1;
|
||||
full <= 0;
|
||||
end
|
||||
else if(clear)
|
||||
begin
|
||||
a <= 0;
|
||||
empty <= 1;
|
||||
full<= 0;
|
||||
end
|
||||
else if(read & ~write)
|
||||
begin
|
||||
full <= 0;
|
||||
if(a==0)
|
||||
empty <= 1;
|
||||
else
|
||||
a <= a - 1;
|
||||
end
|
||||
else if(write & ~read)
|
||||
begin
|
||||
empty <= 0;
|
||||
if(~empty)
|
||||
a <= a + 1;
|
||||
if(a == 30)
|
||||
full <= 1;
|
||||
end
|
||||
|
||||
// NOTE will fail if you write into a full fifo or read from an empty one
|
||||
|
||||
//////////////////////////////////////////////////////////////
|
||||
// space and occupied are used for diagnostics, not
|
||||
// guaranteed correct
|
||||
|
||||
//assign space = full ? 0 : empty ? 16 : 15-a;
|
||||
//assign occupied = empty ? 0 : full ? 16 : a+1;
|
||||
|
||||
always @(posedge clk)
|
||||
if(reset)
|
||||
space <= 6'd32;
|
||||
else if(clear)
|
||||
space <= 6'd32;
|
||||
else if(read & ~write)
|
||||
space <= space + 6'd1;
|
||||
else if(write & ~read)
|
||||
space <= space - 6'd1;
|
||||
|
||||
always @(posedge clk)
|
||||
if(reset)
|
||||
occupied <= 6'd0;
|
||||
else if(clear)
|
||||
occupied <= 6'd0;
|
||||
else if(read & ~write)
|
||||
occupied <= occupied - 6'd1;
|
||||
else if(write & ~read)
|
||||
occupied <= occupied + 6'd1;
|
||||
|
||||
endmodule // axi_fifo_short
|
||||
|
||||
|
||||
Reference in New Issue
Block a user