Files
vortex/hw/rtl/VX_io_arb.v

107 lines
4.3 KiB
Verilog

`include "VX_define.vh"
module VX_io_arb #(
parameter NUM_REQUESTS = 1,
parameter WORD_SIZE = 1,
parameter TAG_IN_WIDTH = 1,
parameter TAG_OUT_WIDTH = 1,
parameter WORD_WIDTH = WORD_SIZE * 8,
parameter ADDR_WIDTH = 32 - `CLOG2(WORD_SIZE),
parameter REQS_BITS = `CLOG2(NUM_REQUESTS)
) (
input wire clk,
input wire reset,
// input requests
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0] in_io_req_valid,
input wire [NUM_REQUESTS-1:0] in_io_req_rw,
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0][WORD_SIZE-1:0] in_io_req_byteen,
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0][ADDR_WIDTH-1:0] in_io_req_addr,
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0][WORD_WIDTH-1:0] in_io_req_data,
input wire [NUM_REQUESTS-1:0][TAG_IN_WIDTH-1:0] in_io_req_tag,
output wire [NUM_REQUESTS-1:0] in_io_req_ready,
// input response
output wire [NUM_REQUESTS-1:0] in_io_rsp_valid,
output wire [NUM_REQUESTS-1:0][WORD_WIDTH-1:0] in_io_rsp_data,
output wire [NUM_REQUESTS-1:0][TAG_IN_WIDTH-1:0] in_io_rsp_tag,
input wire [NUM_REQUESTS-1:0] in_io_rsp_ready,
// output request
output wire [`NUM_THREADS-1:0] out_io_req_valid,
output wire out_io_req_rw,
output wire [`NUM_THREADS-1:0][WORD_SIZE-1:0] out_io_req_byteen,
output wire [`NUM_THREADS-1:0][ADDR_WIDTH-1:0] out_io_req_addr,
output wire [`NUM_THREADS-1:0][WORD_WIDTH-1:0] out_io_req_data,
output wire [TAG_OUT_WIDTH-1:0] out_io_req_tag,
input wire out_io_req_ready,
// output response
input wire out_io_rsp_valid,
input wire [WORD_WIDTH-1:0] out_io_rsp_data,
input wire [TAG_OUT_WIDTH-1:0] out_io_rsp_tag,
output wire out_io_rsp_ready
);
if (NUM_REQUESTS == 1) begin
`UNUSED_VAR (clk)
`UNUSED_VAR (reset)
assign out_io_req_valid = in_io_req_valid;
assign out_io_req_rw = in_io_req_rw;
assign out_io_req_byteen = in_io_req_byteen;
assign out_io_req_addr = in_io_req_addr;
assign out_io_req_data = in_io_req_data;
assign out_io_req_tag = in_io_req_tag;
assign in_io_req_ready = out_io_req_ready;
assign in_io_rsp_valid = out_io_rsp_valid;
assign in_io_rsp_data = out_io_rsp_data;
assign in_io_rsp_tag = out_io_rsp_tag;
assign out_io_rsp_ready = in_io_rsp_ready;
end else begin
reg [REQS_BITS-1:0] bus_req_sel;
wire [NUM_REQUESTS-1:0] valid_requests;
for (genvar i = 0; i < NUM_REQUESTS; i++) begin
assign valid_requests[i] = (| in_io_req_valid[i]);
end
VX_rr_arbiter #(
.N(NUM_REQUESTS)
) arbiter (
.clk (clk),
.reset (reset),
.requests (valid_requests),
.grant_index (bus_req_sel),
`UNUSED_PIN (grant_valid),
`UNUSED_PIN (grant_onehot)
);
assign out_io_req_valid = in_io_req_valid [bus_req_sel];
assign out_io_req_rw = in_io_req_rw [bus_req_sel];
assign out_io_req_byteen = in_io_req_byteen [bus_req_sel];
assign out_io_req_addr = in_io_req_addr [bus_req_sel];
assign out_io_req_data = in_io_req_data [bus_req_sel];
assign out_io_req_tag = {in_io_req_tag [bus_req_sel], REQS_BITS'(bus_req_sel)};
for (genvar i = 0; i < NUM_REQUESTS; i++) begin
assign in_io_req_ready[i] = out_io_req_ready && (bus_req_sel == REQS_BITS'(i));
end
wire [REQS_BITS-1:0] bus_rsp_sel = out_io_rsp_tag[REQS_BITS-1:0];
for (genvar i = 0; i < NUM_REQUESTS; i++) begin
assign in_io_rsp_valid[i] = out_io_rsp_valid && (bus_rsp_sel == REQS_BITS'(i));
assign in_io_rsp_data[i] = out_io_rsp_data;
assign in_io_rsp_tag[i] = out_io_rsp_tag[REQS_BITS +: TAG_IN_WIDTH];
end
assign out_io_rsp_ready = in_io_rsp_ready[bus_rsp_sel];
end
endmodule