Files
kernels/hw/rtl/VX_ibuffer.v
2020-08-26 04:44:36 -07:00

207 lines
8.0 KiB
Verilog

`include "VX_define.vh"
module VX_ibuffer #(
parameter CORE_ID = 0
) (
input wire clk,
input wire reset,
// inputs
input wire freeze, // keep current warp
VX_decode_if ibuf_enq_if,
// outputs
VX_decode_if ibuf_deq_if
);
localparam DATAW = `NUM_THREADS + 32 + `EX_BITS + `OP_BITS + `FRM_BITS + 1 + (`NR_BITS * 4) + 32 + 1 + 1 + 1 + `NUM_REGS;
localparam SIZE = `IBUF_SIZE;
localparam SIZEW = $clog2(SIZE+1);
localparam ADDRW = $clog2(SIZE);
localparam NWARPSW = $clog2(`NUM_WARPS+1);
`USE_FAST_BRAM reg [DATAW-1:0] entries [`NUM_WARPS-1:0][SIZE-1:0];
reg [SIZEW-1:0] size_r [`NUM_WARPS-1:0];
reg [ADDRW:0] rd_ptr_r [`NUM_WARPS-1:0];
reg [ADDRW:0] wr_ptr_r [`NUM_WARPS-1:0];
wire [`NUM_WARPS-1:0] q_full;
wire [`NUM_WARPS-1:0][SIZEW-1:0] q_size;
wire [DATAW-1:0] q_data_in;
wire [`NUM_WARPS-1:0][DATAW-1:0] q_data_prev;
reg [`NUM_WARPS-1:0][DATAW-1:0] q_data_out;
wire enq_fire = ibuf_enq_if.valid && ibuf_enq_if.ready;
wire deq_fire = ibuf_deq_if.valid && ibuf_deq_if.ready;
for (genvar i = 0; i < `NUM_WARPS; ++i) begin
wire writing = enq_fire && (i == ibuf_enq_if.wid);
wire reading = deq_fire && (i == ibuf_deq_if.wid);
wire [ADDRW-1:0] rd_ptr_a = rd_ptr_r[i][ADDRW-1:0];
wire [ADDRW-1:0] wr_ptr_a = wr_ptr_r[i][ADDRW-1:0];
always @(posedge clk) begin
if (reset) begin
rd_ptr_r[i] <= 0;
wr_ptr_r[i] <= 0;
size_r[i] <= 0;
end else begin
if (writing) begin
if ((0 == size_r[i]) || ((1 == size_r[i]) && reading)) begin
q_data_out[i] <= q_data_in;
end else begin
entries[i][wr_ptr_a] <= q_data_in;
wr_ptr_r[i] <= wr_ptr_r[i] + ADDRW'(1);
end
if (!reading) begin
size_r[i] <= size_r[i] + SIZEW'(1);
end
end
if (reading) begin
if (size_r[i] != 1) begin
q_data_out[i] <= q_data_prev[i];
rd_ptr_r[i] <= rd_ptr_r[i] + ADDRW'(1);
end
if (!writing) begin
size_r[i] <= size_r[i] - SIZEW'(1);
end
end
end
end
assign q_data_prev[i] = entries[i][rd_ptr_a];
assign q_full[i] = (size_r[i] == SIZE);
assign q_size[i] = size_r[i];
end
///////////////////////////////////////////////////////////////////////////
reg [`NUM_WARPS-1:0] valid_table, valid_table_n;
reg [`NUM_WARPS-1:0] schedule_table, schedule_table_n;
reg [NWARPSW-1:0] num_warps;
reg [`NW_BITS-1:0] deq_wid, deq_wid_n;
reg deq_valid, deq_valid_n;
reg [DATAW-1:0] deq_instr, deq_instr_n;
always @(*) begin
valid_table_n = valid_table;
if (deq_fire) begin
valid_table_n[ibuf_deq_if.wid] = (q_size[deq_wid] != SIZEW'(1));
end
if (enq_fire) begin
valid_table_n[ibuf_enq_if.wid] = 1;
end
end
always @(*) begin
deq_valid_n = 0;
deq_wid_n = 'x;
deq_instr_n = 'x;
schedule_table_n = schedule_table;
if (0 == num_warps) begin
deq_valid_n = enq_fire;
deq_wid_n = ibuf_enq_if.wid;
deq_instr_n = q_data_in;
end else if ((1 == num_warps) || freeze) begin
deq_valid_n = (!deq_fire || (q_size[deq_wid] != SIZEW'(1))) || enq_fire;
deq_wid_n = (!deq_fire || (q_size[deq_wid] != SIZEW'(1))) ? deq_wid : ibuf_enq_if.wid;
deq_instr_n = deq_fire ? ((q_size[deq_wid] != SIZEW'(1)) ? q_data_prev[deq_wid] : q_data_in) : q_data_out[deq_wid];
end else begin
for (integer i = 0; i < `NUM_WARPS; i++) begin
if (schedule_table_n[i]) begin
deq_valid_n = 1;
deq_wid_n = `NW_BITS'(i);
deq_instr_n = q_data_out[i];
schedule_table_n[i] = 0;
break;
end
end
end
end
wire warp_added = enq_fire && (0 == q_size[ibuf_enq_if.wid]);
wire warp_removed = deq_fire && ~(enq_fire && ibuf_enq_if.wid == ibuf_deq_if.wid) && (1 == q_size[ibuf_deq_if.wid]);
always @(posedge clk) begin
if (reset) begin
valid_table <= 0;
schedule_table <= 0;
deq_valid <= 0;
num_warps <= 0;
end else begin
valid_table <= valid_table_n;
if ((| schedule_table_n)) begin
schedule_table <= schedule_table_n;
end else begin
schedule_table <= valid_table_n;
schedule_table[deq_wid_n] <= 0;
end
deq_valid <= deq_valid_n;
deq_wid <= deq_wid_n;
deq_instr <= deq_instr_n;
if (warp_added && !warp_removed) begin
num_warps <= num_warps + NWARPSW'(1);
end else if (warp_removed && !warp_added) begin
num_warps <= num_warps - NWARPSW'(1);
end
`ifdef VERILATOR
/*if (enq_fire || deq_fire || deq_valid) begin
$display("*** %t: cur=%b(%0d), nxt=%b(%0d), enq=%b(%0d), deq=%b(%0d), nw=%0d(%0d,%0d,%0d,%0d), sched=%b, sched_n=%b",
$time, deq_valid, deq_wid, deq_valid_n, deq_wid_n, enq_fire, ibuf_enq_if.wid, deq_fire, ibuf_deq_if.wid, num_warps, size_r[0], size_r[1], size_r[2], size_r[3], schedule_table, schedule_table_n);
end*/
begin // verify 'num_warps'
integer nw = 0;
for (integer i = 0; i < `NUM_WARPS; i++) begin
nw += 32'(q_size[i] != 0);
end
assert(nw == 32'(num_warps)) else $display("%t: error: invalid num_warps: nw=%0d, ref=%0d", $time, num_warps, nw);
assert(~deq_valid || (q_size[deq_wid] != 0)) else $display("%t: error: invalid schedule: wid=%0d", $time, deq_wid);
assert(~deq_fire || (q_size[deq_wid] != 0)) else $display("%t: error: invalid dequeu: wid=%0d", $time, deq_wid);
end
`endif
end
end
assign ibuf_enq_if.ready = ~q_full[ibuf_enq_if.wid];
assign q_data_in = {ibuf_enq_if.thread_mask,
ibuf_enq_if.curr_PC,
ibuf_enq_if.ex_type,
ibuf_enq_if.op_type,
ibuf_enq_if.op_mod,
ibuf_enq_if.wb,
ibuf_enq_if.rd,
ibuf_enq_if.rs1,
ibuf_enq_if.rs2,
ibuf_enq_if.rs3,
ibuf_enq_if.imm,
ibuf_enq_if.rs1_is_PC,
ibuf_enq_if.rs2_is_imm,
ibuf_enq_if.use_rs3,
ibuf_enq_if.used_regs};
assign ibuf_deq_if.valid = deq_valid;
assign ibuf_deq_if.wid = deq_wid;
assign {ibuf_deq_if.thread_mask,
ibuf_deq_if.curr_PC,
ibuf_deq_if.ex_type,
ibuf_deq_if.op_type,
ibuf_deq_if.op_mod,
ibuf_deq_if.wb,
ibuf_deq_if.rd,
ibuf_deq_if.rs1,
ibuf_deq_if.rs2,
ibuf_deq_if.rs3,
ibuf_deq_if.imm,
ibuf_deq_if.rs1_is_PC,
ibuf_deq_if.rs2_is_imm,
ibuf_deq_if.use_rs3,
ibuf_deq_if.used_regs} = deq_instr;
endmodule