Files
kernels/hw/rtl/mem/VX_shared_mem.sv
Blaise Tine c6845a4c8d profiling timing optimization
minor update

minor update

minor update
2023-12-18 04:43:10 -08:00

338 lines
12 KiB
Systemverilog

// Copyright © 2019-2023
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
`include "VX_define.vh"
module VX_shared_mem import VX_gpu_pkg::*; #(
parameter `STRING INSTANCE_ID = "",
// Size of cache in bytes
parameter SIZE = (1024*16*8),
// Number of Word requests per cycle
parameter NUM_REQS = 4,
// Number of banks
parameter NUM_BANKS = 4,
// Address width
parameter ADDR_WIDTH = `CLOG2(SIZE),
// Size of a word in bytes
parameter WORD_SIZE = `XLEN/8,
// Request debug identifier
parameter UUID_WIDTH = 0,
// Request tag size
parameter TAG_WIDTH = 16
) (
input wire clk,
input wire reset,
// PERF
`ifdef PERF_ENABLE
output cache_perf_t cache_perf,
`endif
// Core request
input wire [NUM_REQS-1:0] req_valid,
input wire [NUM_REQS-1:0] req_rw,
input wire [NUM_REQS-1:0][ADDR_WIDTH-1:0] req_addr,
input wire [NUM_REQS-1:0][WORD_SIZE-1:0] req_byteen,
input wire [NUM_REQS-1:0][WORD_SIZE*8-1:0] req_data,
input wire [NUM_REQS-1:0][TAG_WIDTH-1:0] req_tag,
output wire [NUM_REQS-1:0] req_ready,
// Core response
output wire [NUM_REQS-1:0] rsp_valid,
output wire [NUM_REQS-1:0][WORD_SIZE*8-1:0] rsp_data,
output wire [NUM_REQS-1:0][TAG_WIDTH-1:0] rsp_tag,
input wire [NUM_REQS-1:0] rsp_ready
);
`UNUSED_SPARAM (INSTANCE_ID)
`UNUSED_PARAM (UUID_WIDTH)
localparam REQ_SEL_BITS = `CLOG2(NUM_REQS);
localparam REQ_SEL_WIDTH = `UP(REQ_SEL_BITS);
localparam WORD_WIDTH = WORD_SIZE * 8;
localparam NUM_WORDS = SIZE / WORD_SIZE;
localparam WORDS_PER_BANK = NUM_WORDS / NUM_BANKS;
localparam BANK_ADDR_WIDTH = `CLOG2(WORDS_PER_BANK);
localparam BANK_SEL_BITS = `CLOG2(NUM_BANKS);
localparam BANK_SEL_WIDTH = `UP(BANK_SEL_BITS);
localparam REQ_DATAW = 1 + BANK_ADDR_WIDTH + WORD_SIZE + WORD_WIDTH + TAG_WIDTH;
localparam RSP_DATAW = WORD_WIDTH + TAG_WIDTH;
`STATIC_ASSERT(ADDR_WIDTH == (BANK_ADDR_WIDTH + `CLOG2(NUM_BANKS)), ("invalid parameter"))
// bank selection
wire [NUM_REQS-1:0][BANK_SEL_WIDTH-1:0] req_bank_idx;
if (NUM_BANKS > 1) begin
for (genvar i = 0; i < NUM_REQS; ++i) begin
assign req_bank_idx[i] = req_addr[i][0 +: BANK_SEL_BITS];
end
end else begin
assign req_bank_idx = 0;
end
// bank addressing
wire [NUM_REQS-1:0][BANK_ADDR_WIDTH-1:0] req_bank_addr;
for (genvar i = 0; i < NUM_REQS; ++i) begin
assign req_bank_addr[i] = req_addr[i][BANK_SEL_BITS +: BANK_ADDR_WIDTH];
end
// bank requests dispatch
wire [NUM_BANKS-1:0] per_bank_req_valid;
wire [NUM_BANKS-1:0] per_bank_req_rw;
wire [NUM_BANKS-1:0][BANK_ADDR_WIDTH-1:0] per_bank_req_addr;
wire [NUM_BANKS-1:0][WORD_SIZE-1:0] per_bank_req_byteen;
wire [NUM_BANKS-1:0][WORD_WIDTH-1:0] per_bank_req_data;
wire [NUM_BANKS-1:0][TAG_WIDTH-1:0] per_bank_req_tag;
wire [NUM_BANKS-1:0][REQ_SEL_WIDTH-1:0] per_bank_req_idx;
wire [NUM_BANKS-1:0] per_bank_req_ready;
wire [NUM_REQS-1:0][REQ_DATAW-1:0] req_data_in;
wire [NUM_BANKS-1:0][REQ_DATAW-1:0] req_data_out;
`ifdef PERF_ENABLE
wire [`PERF_CTR_BITS-1:0] perf_collisions;
`endif
for (genvar i = 0; i < NUM_REQS; ++i) begin
assign req_data_in[i] = {
req_rw[i],
req_bank_addr[i],
req_byteen[i],
req_data[i],
req_tag[i]};
end
VX_stream_xbar #(
.NUM_INPUTS (NUM_REQS),
.NUM_OUTPUTS (NUM_BANKS),
.DATAW (REQ_DATAW),
.PERF_CTR_BITS (`PERF_CTR_BITS),
.OUT_REG (3) // output should be registered for the data_store addressing
) req_xbar (
.clk (clk),
.reset (reset),
`ifdef PERF_ENABLE
.collisions (perf_collisions),
`else
`UNUSED_PIN (collisions),
`endif
.valid_in (req_valid),
.data_in (req_data_in),
.sel_in (req_bank_idx),
.ready_in (req_ready),
.valid_out (per_bank_req_valid),
.data_out (req_data_out),
.sel_out (per_bank_req_idx),
.ready_out (per_bank_req_ready)
);
for (genvar i = 0; i < NUM_BANKS; ++i) begin
assign {
per_bank_req_rw[i],
per_bank_req_addr[i],
per_bank_req_byteen[i],
per_bank_req_data[i],
per_bank_req_tag[i]} = req_data_out[i];
end
// banks access
wire [NUM_BANKS-1:0] per_bank_rsp_valid;
wire [NUM_BANKS-1:0][WORD_WIDTH-1:0] per_bank_rsp_data;
wire [NUM_BANKS-1:0][REQ_SEL_WIDTH-1:0] per_bank_rsp_idx;
wire [NUM_BANKS-1:0][TAG_WIDTH-1:0] per_bank_rsp_tag;
wire [NUM_BANKS-1:0] per_bank_rsp_ready;
for (genvar i = 0; i < NUM_BANKS; ++i) begin
VX_sp_ram #(
.DATAW (WORD_WIDTH),
.SIZE (WORDS_PER_BANK),
.WRENW (WORD_SIZE)
) data_store (
.clk (clk),
.read (1'b1),
.write (per_bank_req_valid[i] && per_bank_req_ready[i] && per_bank_req_rw[i]),
.wren (per_bank_req_byteen[i]),
.addr (per_bank_req_addr[i]),
.wdata (per_bank_req_data[i]),
.rdata (per_bank_rsp_data[i])
);
// drop write response
wire per_bank_req_valid_w, per_bank_req_ready_w;
assign per_bank_req_valid_w = per_bank_req_valid[i] && ~per_bank_req_rw[i];
assign per_bank_req_ready[i] = per_bank_req_ready_w || per_bank_req_rw[i];
VX_elastic_buffer #(
.DATAW (REQ_SEL_WIDTH + TAG_WIDTH),
.SIZE (0)
) bank_buf (
.clk (clk),
.reset (reset),
.valid_in (per_bank_req_valid_w),
.ready_in (per_bank_req_ready_w),
.data_in ({per_bank_req_idx[i], per_bank_req_tag[i]}),
.data_out ({per_bank_rsp_idx[i], per_bank_rsp_tag[i]}),
.valid_out (per_bank_rsp_valid[i]),
.ready_out (per_bank_rsp_ready[i])
);
end
// bank responses gather
wire [NUM_BANKS-1:0][RSP_DATAW-1:0] rsp_data_in;
wire [NUM_REQS-1:0][RSP_DATAW-1:0] rsp_data_out;
for (genvar i = 0; i < NUM_BANKS; ++i) begin
assign rsp_data_in[i] = {per_bank_rsp_data[i], per_bank_rsp_tag[i]};
end
VX_stream_xbar #(
.NUM_INPUTS (NUM_BANKS),
.NUM_OUTPUTS (NUM_REQS),
.DATAW (RSP_DATAW),
.OUT_REG (2)
) rsp_xbar (
.clk (clk),
.reset (reset),
`UNUSED_PIN (collisions),
.sel_in (per_bank_rsp_idx),
.valid_in (per_bank_rsp_valid),
.ready_in (per_bank_rsp_ready),
.data_in (rsp_data_in),
.data_out (rsp_data_out),
.valid_out (rsp_valid),
.ready_out (rsp_ready),
`UNUSED_PIN (sel_out)
);
for (genvar i = 0; i < NUM_REQS; ++i) begin
assign {rsp_data[i], rsp_tag[i]} = rsp_data_out[i];
end
`ifdef PERF_ENABLE
// per cycle: reads, writes
wire [`CLOG2(NUM_REQS+1)-1:0] perf_reads_per_cycle;
wire [`CLOG2(NUM_REQS+1)-1:0] perf_writes_per_cycle;
wire [`CLOG2(NUM_REQS+1)-1:0] perf_crsp_stall_per_cycle;
wire [NUM_REQS-1:0] perf_reads_per_req, perf_writes_per_req;
wire [NUM_REQS-1:0] perf_crsp_stall_per_req = rsp_valid & ~rsp_ready;
`BUFFER(perf_reads_per_req, req_valid & req_ready & ~req_rw);
`BUFFER(perf_writes_per_req, req_valid & req_ready & req_rw);
`POP_COUNT(perf_reads_per_cycle, perf_reads_per_req);
`POP_COUNT(perf_writes_per_cycle, perf_writes_per_req);
`POP_COUNT(perf_crsp_stall_per_cycle, perf_crsp_stall_per_req);
reg [`PERF_CTR_BITS-1:0] perf_reads;
reg [`PERF_CTR_BITS-1:0] perf_writes;
reg [`PERF_CTR_BITS-1:0] perf_crsp_stalls;
always @(posedge clk) begin
if (reset) begin
perf_reads <= '0;
perf_writes <= '0;
perf_crsp_stalls <= '0;
end else begin
perf_reads <= perf_reads + `PERF_CTR_BITS'(perf_reads_per_cycle);
perf_writes <= perf_writes + `PERF_CTR_BITS'(perf_writes_per_cycle);
perf_crsp_stalls <= perf_crsp_stalls + `PERF_CTR_BITS'(perf_crsp_stall_per_cycle);
end
end
assign cache_perf.reads = perf_reads;
assign cache_perf.writes = perf_writes;
assign cache_perf.read_misses = '0;
assign cache_perf.write_misses = '0;
assign cache_perf.bank_stalls = perf_collisions;
assign cache_perf.mshr_stalls = '0;
assign cache_perf.mem_stalls = '0;
assign cache_perf.crsp_stalls = perf_crsp_stalls;
`endif
`ifdef DBG_TRACE_CACHE_BANK
wire [NUM_REQS-1:0][`UP(UUID_WIDTH)-1:0] req_uuid;
wire [NUM_REQS-1:0][`UP(UUID_WIDTH)-1:0] rsp_uuid;
for (genvar i = 0; i < NUM_REQS; ++i) begin
if (UUID_WIDTH != 0) begin
assign req_uuid[i] = req_tag[i][TAG_WIDTH-1 -: UUID_WIDTH];
assign rsp_uuid[i] = rsp_tag[i][TAG_WIDTH-1 -: UUID_WIDTH];
end else begin
assign req_uuid[i] = 0;
assign rsp_uuid[i] = 0;
end
end
wire [NUM_BANKS-1:0][`UP(UUID_WIDTH)-1:0] per_bank_req_uuid;
wire [NUM_BANKS-1:0][`UP(UUID_WIDTH)-1:0] per_bank_rsp_uuid;
for (genvar i = 0; i < NUM_BANKS; ++i) begin
if (UUID_WIDTH != 0) begin
assign per_bank_req_uuid[i] = per_bank_req_tag[i][TAG_WIDTH-1 -: UUID_WIDTH];
assign per_bank_rsp_uuid[i] = per_bank_rsp_tag[i][TAG_WIDTH-1 -: UUID_WIDTH];
end else begin
assign per_bank_req_uuid[i] = 0;
assign per_bank_rsp_uuid[i] = 0;
end
end
always @(posedge clk) begin
for (integer i = 0; i < NUM_REQS; ++i) begin
if (req_valid[i] && req_ready[i]) begin
if (req_rw[i]) begin
`TRACE(1, ("%d: %s wr-req: req_idx=%0d, addr=0x%0h, tag=0x%0h, byteen=%b, data=0x%0h (#%0d)\n",
$time, INSTANCE_ID, i, req_addr[i], req_tag[i], req_byteen[i], req_data[i], req_uuid[i]));
end else begin
`TRACE(1, ("%d: %s rd-req: req_idx=%0d, addr=0x%0h, tag=0x%0h (#%0d)\n",
$time, INSTANCE_ID, i, req_addr[i], req_tag[i], req_uuid[i]));
end
end
if (rsp_valid[i] && rsp_ready[i]) begin
`TRACE(1, ("%d: %s rd-rsp: req_idx=%0d, tag=0x%0h, data=0x%0h (#%0d)\n",
$time, INSTANCE_ID, i, rsp_tag[i], rsp_data[i], rsp_uuid[i]));
end
end
for (integer i = 0; i < NUM_BANKS; ++i) begin
if (per_bank_req_valid[i] && per_bank_req_ready[i]) begin
if (per_bank_req_rw[i]) begin
`TRACE(2, ("%d: %s-bank%0d wr-req: addr=0x%0h, tag=0x%0h, byteen=%b, data=0x%0h (#%0d)\n",
$time, INSTANCE_ID, i, per_bank_req_addr[i], per_bank_req_tag[i], per_bank_req_byteen[i], per_bank_req_data[i], per_bank_req_uuid[i]));
end else begin
`TRACE(2, ("%d: %s-bank%0d rd-req: addr=0x%0h, tag=0x%0h (#%0d)\n",
$time, INSTANCE_ID, i, per_bank_req_addr[i], per_bank_req_tag[i], per_bank_req_uuid[i]));
end
end
if (per_bank_rsp_valid[i] && per_bank_rsp_ready[i]) begin
`TRACE(2, ("%d: %s-bank%0d rd-rsp: tag=0x%0h, data=0x%0h (#%0d)\n",
$time, INSTANCE_ID, i, per_bank_rsp_tag[i], per_bank_rsp_data[i], per_bank_rsp_uuid[i]));
end
end
end
`endif
endmodule