Files
kernels/rtl/VX_fetch.v
2019-05-10 00:49:54 -07:00

152 lines
4.5 KiB
Verilog

`include "VX_define.v"
module VX_fetch (
input wire clk,
input wire reset,
input wire in_branch_dir,
input wire in_freeze,
input wire[31:0] in_branch_dest,
input wire in_branch_stall,
input wire in_fwd_stall,
input wire in_branch_stall_exe,
input wire in_clone_stall,
input wire in_jal,
input wire[31:0] in_jal_dest,
input wire in_interrupt,
input wire in_debug,
input wire[31:0] in_instruction,
input wire in_thread_mask[`NT_M1:0],
input wire in_change_mask,
input wire[`NW_M1:0] in_decode_warp_num,
input wire[`NW_M1:0] in_memory_warp_num,
input wire in_wspawn,
input wire[31:0] in_wspawn_pc,
input wire in_ebreak,
output wire[31:0] out_instruction,
output wire out_delay,
output wire[`NW_M1:0] out_warp_num,
output wire[31:0] out_curr_PC,
output wire out_valid[`NT_M1:0],
output wire out_ebreak
);
reg stall;
reg[31:0] out_PC;
reg[`NW_M1:0] warp_num;
reg[`NW_M1:0] warp_state;
initial begin
warp_num = 0;
warp_state = 0;
end
wire add_warp = in_wspawn && !in_ebreak && !in_clone_stall;
wire remove_warp = in_ebreak && !in_wspawn && !in_clone_stall;
always @(posedge clk or posedge reset) begin
if (reset || (warp_num == warp_state) || remove_warp || add_warp) begin
warp_num <= 0;
end else begin
warp_num <= warp_num + 1;
end
if (add_warp) begin
// $display("Adding a new warp %h", warp_state);
warp_state <= warp_state + 1;
end else if (remove_warp) begin
// $display("Removing a warp %h", warp_state);
warp_state <= warp_state - 1;
end
end
assign out_ebreak = (warp_state == 0) && in_ebreak;
assign stall = in_clone_stall || in_branch_stall || in_fwd_stall || in_branch_stall_exe || in_interrupt || in_freeze || in_debug;
wire warp_zero_change_mask = in_change_mask && (in_decode_warp_num == 0);
wire warp_zero_jal = in_jal && (in_memory_warp_num == 0);
wire warp_zero_branch = in_branch_dir && (in_memory_warp_num == 0);
wire warp_zero_stall = stall || (warp_num == 1);
wire warp_zero_wspawn = 0;
wire[31:0] warp_zero_wspawn_pc = 32'h0;
wire[31:0] warp_zero_pc;
wire warp_zero_valid[`NT_M1:0];
VX_warp VX_Warp_zero(
.clk (clk),
.reset (reset),
.stall (warp_zero_stall),
.in_thread_mask(in_thread_mask),
.in_change_mask(warp_zero_change_mask),
.in_jal (warp_zero_jal),
.in_jal_dest (in_jal_dest),
.in_branch_dir (warp_zero_branch),
.in_branch_dest(in_branch_dest),
.in_wspawn (warp_zero_wspawn),
.in_wspawn_pc (warp_zero_wspawn_pc),
.out_PC (warp_zero_pc),
.out_valid (warp_zero_valid)
);
wire warp_one_change_mask = in_change_mask && (in_decode_warp_num == 1);
wire warp_one_jal = in_jal && (in_memory_warp_num == 1);
wire warp_one_branch = in_branch_dir && (in_memory_warp_num == 1);
wire warp_one_stall = stall || (warp_num == 0);
wire[31:0] warp_one_pc;
wire warp_one_valid[`NT_M1:0];
VX_warp VX_Warp_one(
.clk (clk),
.reset (reset),
.stall (warp_one_stall),
.in_thread_mask(in_thread_mask),
.in_change_mask(warp_one_change_mask),
.in_jal (warp_one_jal),
.in_jal_dest (in_jal_dest),
.in_branch_dir (warp_one_branch),
.in_branch_dest(in_branch_dest),
.in_wspawn (in_wspawn),
.in_wspawn_pc (in_wspawn_pc),
.out_PC (warp_one_pc),
.out_valid (warp_one_valid)
);
// always @(*) begin
// if (in_wspawn) begin
// $display("Spawning a warp @ %h",in_wspawn_pc);
// end
// end
// always @(posedge clk) begin
// $display("curr warp: %h Threads:%d%d PC: %h", warp_num, out_valid[0],out_valid[1], out_PC);
// end
// always @(*) begin
// if (warp_num == 1) begin
// $display("Going to PC: %h", warp_one_pc);
// end
// end
assign out_PC = (warp_num == 0) ? warp_zero_pc : warp_one_pc;
assign out_valid = (warp_num == 0) ? warp_zero_valid : warp_one_valid;
// always @(*) begin
// $display("FETCH PC: %h (%h, %h, %h)",delete, delete, in_jal_dest, in_branch_dest);
// end
assign out_curr_PC = out_PC;
assign out_warp_num = warp_num;
assign out_delay = 0;
assign out_instruction = stall ? 32'b0 : in_instruction;
endmodule