Files
vortex/hw/rtl/cache/VX_cache_miss_resrv.v
2020-06-19 09:12:07 -07:00

172 lines
7.1 KiB
Verilog

`include "VX_cache_config.vh"
module VX_cache_miss_resrv #(
parameter CACHE_ID = 0,
parameter BANK_ID = 0,
// Size of line inside a bank in bytes
parameter BANK_LINE_SIZE = 0,
// Number of banks {1, 2, 4, 8,...}
parameter NUM_BANKS = 0,
// Size of a word in bytes
parameter WORD_SIZE = 0,
// Number of Word requests per cycle {1, 2, 4, 8, ...}
parameter NUM_REQUESTS = 0,
// Miss Reserv Queue Knob
parameter MRVQ_SIZE = 0,
// core request tag size
parameter CORE_TAG_WIDTH = 0,
// Snooping request tag width
parameter SNP_REQ_TAG_WIDTH = 0
) (
input wire clk,
input wire reset,
// Miss enqueue
input wire miss_add,
input wire from_mrvq,
input wire[`LINE_ADDR_WIDTH-1:0] miss_add_addr,
input wire[`UP(`WORD_SELECT_WIDTH)-1:0] miss_add_wsel,
input wire[`WORD_WIDTH-1:0] miss_add_data,
input wire[`REQS_BITS-1:0] miss_add_tid,
input wire[`REQ_TAG_WIDTH-1:0] miss_add_tag,
input wire miss_add_rw,
input wire[WORD_SIZE-1:0] miss_add_byteen,
input wire mrvq_init_ready_state,
input wire miss_add_is_snp,
input wire miss_add_snp_invalidate,
output wire miss_resrv_full,
output wire miss_resrv_stop,
// Broadcast Address
input wire is_fill_st1,
input wire[`LINE_ADDR_WIDTH-1:0] fill_addr_st1,
output wire pending_hazard,
// Miss dequeue
input wire miss_resrv_pop,
output wire miss_resrv_valid_st0,
output wire[`LINE_ADDR_WIDTH-1:0] miss_resrv_addr_st0,
output wire[`UP(`WORD_SELECT_WIDTH)-1:0] miss_resrv_wsel_st0,
output wire[`WORD_WIDTH-1:0] miss_resrv_data_st0,
output wire[`REQS_BITS-1:0] miss_resrv_tid_st0,
output wire[`REQ_TAG_WIDTH-1:0] miss_resrv_tag_st0,
output wire miss_resrv_rw_st0,
output wire[WORD_SIZE-1:0] miss_resrv_byteen_st0,
output wire miss_resrv_is_snp_st0,
output wire miss_resrv_snp_invalidate_st0
);
reg [`MRVQ_METADATA_WIDTH-1:0] metadata_table[MRVQ_SIZE-1:0];
reg [MRVQ_SIZE-1:0][`LINE_ADDR_WIDTH-1:0] addr_table;
reg [MRVQ_SIZE-1:0] valid_table;
reg [MRVQ_SIZE-1:0] ready_table;
reg [`LOG2UP(MRVQ_SIZE)-1:0] schedule_ptr;
reg [`LOG2UP(MRVQ_SIZE)-1:0] head_ptr;
reg [`LOG2UP(MRVQ_SIZE)-1:0] tail_ptr;
reg [`LOG2UP(MRVQ_SIZE+1)-1:0] size;
`STATIC_ASSERT(MRVQ_SIZE > 5, "invalid size");
assign miss_resrv_full = (size == $bits(size)'(MRVQ_SIZE));
assign miss_resrv_stop = (size > $bits(size)'(MRVQ_SIZE-5)); // need to add 5 cycles to prevent pipeline lock
wire enqueue_possible = !miss_resrv_full;
wire [`LOG2UP(MRVQ_SIZE)-1:0] enqueue_index = tail_ptr;
reg [MRVQ_SIZE-1:0] make_ready;
reg [MRVQ_SIZE-1:0] make_ready_push;
reg [MRVQ_SIZE-1:0] valid_address_match;
genvar i;
generate
for (i = 0; i < MRVQ_SIZE; i++) begin
assign valid_address_match[i] = valid_table[i] && (addr_table[i] === fill_addr_st1);
assign make_ready[i] = is_fill_st1 && valid_address_match[i];
end
endgenerate
assign pending_hazard = |(valid_address_match);
wire dequeue_possible = valid_table[schedule_ptr] && ready_table[schedule_ptr];
wire [`LOG2UP(MRVQ_SIZE)-1:0] dequeue_index = schedule_ptr;
assign miss_resrv_valid_st0 = dequeue_possible;
assign miss_resrv_addr_st0 = addr_table[dequeue_index];
assign {miss_resrv_data_st0, miss_resrv_tid_st0, miss_resrv_tag_st0, miss_resrv_rw_st0, miss_resrv_byteen_st0, miss_resrv_wsel_st0, miss_resrv_is_snp_st0, miss_resrv_snp_invalidate_st0} = metadata_table[dequeue_index];
wire mrvq_push = miss_add && enqueue_possible && !from_mrvq;
wire mrvq_pop = miss_resrv_pop && dequeue_possible;
wire recover_state = miss_add && from_mrvq;
wire increment_head = !miss_add && from_mrvq;
wire update_ready = (|make_ready);
wire qual_mrvq_init = mrvq_push && mrvq_init_ready_state;
assign make_ready_push = (MRVQ_SIZE'(qual_mrvq_init)) << enqueue_index;
always @(posedge clk) begin
if (reset) begin
valid_table <= 0;
ready_table <= 0;
size <= 0;
schedule_ptr <= 0;
head_ptr <= 0;
tail_ptr <= 0;
end else begin
if (mrvq_push) begin
valid_table[enqueue_index] <= 1;
ready_table[enqueue_index] <= mrvq_init_ready_state;
addr_table[enqueue_index] <= miss_add_addr;
metadata_table[enqueue_index] <= {miss_add_data, miss_add_tid, miss_add_tag, miss_add_rw, miss_add_byteen, miss_add_wsel, miss_add_is_snp, miss_add_snp_invalidate};
tail_ptr <= tail_ptr + 1;
end else if (increment_head) begin
valid_table[head_ptr] <= 0;
head_ptr <= head_ptr + 1;
end else if (recover_state) begin
schedule_ptr <= schedule_ptr - 1;
end
// update entry as 'ready' during DRAM fill response
if (update_ready) begin
ready_table <= ready_table | make_ready | make_ready_push;
end
if (mrvq_pop) begin
ready_table[dequeue_index] <= 0;
schedule_ptr <= schedule_ptr + 1;
end
if (!(mrvq_push && increment_head)) begin
if (mrvq_push) begin
size <= size + 1;
end
if (increment_head) begin
size <= size - 1;
end
end
end
end
`ifdef DBG_PRINT_CACHE_MSRQ
integer j;
always @(posedge clk) begin
if (mrvq_push || mrvq_pop || increment_head || recover_state) begin
$write("%t: bank%0d-%0d msrq: push=%b pop=%b incr=%d recv=%d", $time, CACHE_ID, BANK_ID, mrvq_push, mrvq_pop, increment_head, recover_state);
for (j = 0; j < MRVQ_SIZE; j++) begin
if (valid_table[j]) begin
$write(" ");
if (schedule_ptr == $bits(schedule_ptr)'(j)) $write("*");
if (~ready_table[j]) $write("!");
$write("addr%0d=%0h", j, `LINE_TO_BYTE_ADDR(addr_table[j], BANK_ID));
end
end
$write("\n");
end
end
`endif
endmodule