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] io_req_valid_in,
input wire [NUM_REQUESTS-1:0] io_req_rw_in,
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0][WORD_SIZE-1:0] io_req_byteen_in,
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0][ADDR_WIDTH-1:0] io_req_addr_in,
input wire [NUM_REQUESTS-1:0][`NUM_THREADS-1:0][WORD_WIDTH-1:0] io_req_data_in,
input wire [NUM_REQUESTS-1:0][TAG_IN_WIDTH-1:0] io_req_tag_in,
output wire [NUM_REQUESTS-1:0] io_req_ready_in,
// input response
output wire [NUM_REQUESTS-1:0] io_rsp_valid_in,
output wire [NUM_REQUESTS-1:0][WORD_WIDTH-1:0] io_rsp_data_in,
output wire [NUM_REQUESTS-1:0][TAG_IN_WIDTH-1:0] io_rsp_tag_in,
input wire [NUM_REQUESTS-1:0] io_rsp_ready_in,
// output request
output wire [`NUM_THREADS-1:0] io_req_valid_out,
output wire io_req_rw_out,
output wire [`NUM_THREADS-1:0][WORD_SIZE-1:0] io_req_byteen_out,
output wire [`NUM_THREADS-1:0][ADDR_WIDTH-1:0] io_req_addr_out,
output wire [`NUM_THREADS-1:0][WORD_WIDTH-1:0] io_req_data_out,
output wire [TAG_OUT_WIDTH-1:0] io_req_tag_out,
input wire io_req_ready_out,
// output response
input wire io_rsp_valid_out,
input wire [WORD_WIDTH-1:0] io_rsp_data_out,
input wire [TAG_OUT_WIDTH-1:0] io_rsp_tag_out,
output wire io_rsp_ready_out
);
if (NUM_REQUESTS == 1) begin
`UNUSED_VAR (clk)
`UNUSED_VAR (reset)
assign io_req_valid_out = io_req_valid_in;
assign io_req_rw_out = io_req_rw_in;
assign io_req_byteen_out = io_req_byteen_in;
assign io_req_addr_out = io_req_addr_in;
assign io_req_data_out = io_req_data_in;
assign io_req_tag_out = io_req_tag_in;
assign io_req_ready_in = io_req_ready_out;
assign io_rsp_valid_in = io_rsp_valid_out;
assign io_rsp_data_in = io_rsp_data_out;
assign io_rsp_tag_in = io_rsp_tag_out;
assign io_rsp_ready_out = io_rsp_ready_in;
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] = (| io_req_valid_in[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 io_req_valid_out = io_req_valid_in [bus_req_sel];
assign io_req_rw_out = io_req_rw_in [bus_req_sel];
assign io_req_byteen_out = io_req_byteen_in [bus_req_sel];
assign io_req_addr_out = io_req_addr_in [bus_req_sel];
assign io_req_data_out = io_req_data_in [bus_req_sel];
assign io_req_tag_out = {io_req_tag_in [bus_req_sel], REQS_BITS'(bus_req_sel)};
for (genvar i = 0; i < NUM_REQUESTS; i++) begin
assign io_req_ready_in[i] = io_req_ready_out && (bus_req_sel == REQS_BITS'(i));
end
wire [REQS_BITS-1:0] bus_rsp_sel = io_rsp_tag_out[REQS_BITS-1:0];
for (genvar i = 0; i < NUM_REQUESTS; i++) begin
assign io_rsp_valid_in[i] = io_rsp_valid_out && (bus_rsp_sel == REQS_BITS'(i));
assign io_rsp_data_in[i] = io_rsp_data_out;
assign io_rsp_tag_in[i] = io_rsp_tag_out[REQS_BITS +: TAG_IN_WIDTH];
end
assign io_rsp_ready_out = io_rsp_ready_in[bus_rsp_sel];
end
endmodule