Files
vortex/hw/rtl/libs/VX_generic_queue.v
2020-12-06 14:42:12 -08:00

182 lines
5.5 KiB
Verilog

`include "VX_platform.vh"
module VX_generic_queue #(
parameter DATAW = 1,
parameter SIZE = 2,
parameter BUFFERED = 0,
parameter ADDRW = $clog2(SIZE),
parameter SIZEW = $clog2(SIZE+1),
parameter FASTRAM = 0
) (
input wire clk,
input wire reset,
input wire push,
input wire pop,
input wire [DATAW-1:0] data_in,
output wire [DATAW-1:0] data_out,
output wire empty,
output wire full,
output wire [SIZEW-1:0] size
);
`STATIC_ASSERT(`ISPOW2(SIZE), ("must be 0 or power of 2!"))
if (SIZE == 1) begin
reg [DATAW-1:0] head_r;
reg size_r;
always @(posedge clk) begin
if (reset) begin
head_r <= 0;
size_r <= 0;
end else begin
if (push && !pop) begin
assert(!full);
size_r <= 1;
end else if (pop && !push) begin
assert(!empty);
size_r <= 0;
end
if (push) begin
head_r <= data_in;
end
end
end
assign data_out = head_r;
assign empty = (size_r == 0);
assign full = (size_r != 0);
assign size = size_r;
end else begin
reg empty_r;
reg full_r;
reg [ADDRW-1:0] used_r;
always @(posedge clk) begin
if (reset) begin
empty_r <= 1;
full_r <= 0;
used_r <= 0;
end else begin
if (push) begin
assert(!full);
if (!pop) begin
empty_r <= 0;
if (used_r == ADDRW'(SIZE-1)) begin
full_r <= 1;
end
end
end
if (pop) begin
assert(!empty);
if (!push) begin
full_r <= 0;
if (used_r == ADDRW'(1)) begin
empty_r <= 1;
end;
end
end
used_r <= used_r + ADDRW'(push) - ADDRW'(pop);
end
end
if (0 == BUFFERED) begin
reg [ADDRW:0] rd_ptr_r;
reg [ADDRW:0] wr_ptr_r;
wire [ADDRW-1:0] rd_ptr_a = rd_ptr_r[ADDRW-1:0];
wire [ADDRW-1:0] wr_ptr_a = wr_ptr_r[ADDRW-1:0];
always @(posedge clk) begin
if (reset) begin
rd_ptr_r <= 0;
wr_ptr_r <= 0;
end else begin
wr_ptr_r <= wr_ptr_r + (ADDRW+1)'(push);
rd_ptr_r <= rd_ptr_r + (ADDRW+1)'(pop);
end
end
VX_dp_ram #(
.DATAW(DATAW),
.SIZE(SIZE),
.BUFFERED(0),
.RWCHECK(1),
.FASTRAM(FASTRAM)
) dp_ram (
.clk(clk),
.waddr(wr_ptr_a),
.raddr(rd_ptr_a),
.wren(push),
.byteen(1'b1),
.rden(1'b1),
.din(data_in),
.dout(data_out)
);
end else begin
wire [DATAW-1:0] dout;
reg [DATAW-1:0] dout_r;
reg [ADDRW-1:0] wr_ptr_r;
reg [ADDRW-1:0] rd_ptr_r;
reg [ADDRW-1:0] rd_ptr_n_r;
always @(posedge clk) begin
if (reset) begin
wr_ptr_r <= 0;
rd_ptr_r <= 0;
rd_ptr_n_r <= 1;
end else begin
if (push) begin
wr_ptr_r <= wr_ptr_r + ADDRW'(1);
end
if (pop) begin
rd_ptr_r <= rd_ptr_n_r;
if (SIZE > 2) begin
rd_ptr_n_r <= rd_ptr_r + ADDRW'(2);
end else begin // (SIZE == 2);
rd_ptr_n_r <= ~rd_ptr_n_r;
end
end
end
end
VX_dp_ram #(
.DATAW(DATAW),
.SIZE(SIZE),
.BUFFERED(0),
.RWCHECK(0),
.FASTRAM(FASTRAM)
) dp_ram (
.clk(clk),
.waddr(wr_ptr_r),
.raddr(rd_ptr_n_r),
.wren(push),
.byteen(1'b1),
.rden(1'b1),
.din(data_in),
.dout(dout)
);
always @(posedge clk) begin
if (push && (empty_r || ((used_r == ADDRW'(1)) && pop))) begin
dout_r <= data_in;
end else if (pop) begin
dout_r <= dout;
end
end
assign data_out = dout_r;
end
assign empty = empty_r;
assign full = full_r;
assign size = {full_r, used_r};
end
endmodule