decoder logic specialization

vortexgpgpu · Sep 1, 2024 · d979cf2 · d979cf2
1 parent 72c63a4
commit d979cf2
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Showing 12 changed files with 116 additions and 22 deletions.
diff --git a/hw/rtl/afu/opae/vortex_afu.sv b/hw/rtl/afu/opae/vortex_afu.sv
@@ -963,7 +963,7 @@ module vortex_afu import ccip_if_pkg::*; import local_mem_cfg_pkg::*; import VX_
 
     wire [COUT_TID_WIDTH-1:0] cout_tid;
 
-    VX_onehot_encoder #(
+    VX_encoder #(
         .N (`VX_MEM_BYTEEN_WIDTH)
     ) cout_tid_enc (
         .data_in  (vx_mem_req_byteen),

diff --git a/hw/rtl/cache/VX_bank_flush.sv b/hw/rtl/cache/VX_bank_flush.sv
@@ -114,7 +114,13 @@ module VX_bank_flush #(
     assign flush_line  = counter_r[`CS_LINE_SEL_BITS-1:0];
 
     if (WRITEBACK && `CS_WAY_SEL_BITS > 0) begin
-        assign flush_way = NUM_WAYS'(1) << counter_r[`CS_LINE_SEL_BITS +: `CS_WAY_SEL_BITS];
+        VX_decoder #(
+            .N (`CS_WAY_SEL_BITS)
+        ) ctr_decoder (
+            .shift_in (counter_r[`CS_LINE_SEL_BITS +: `CS_WAY_SEL_BITS]),
+            .data_in  (1'b1),
+            .data_out (flush_way)
+        );
     end else begin
         assign flush_way = {NUM_WAYS{1'b1}};
     end

diff --git a/hw/rtl/cache/VX_cache_bypass.sv b/hw/rtl/cache/VX_cache_bypass.sv
@@ -56,6 +56,7 @@ module VX_cache_bypass #(
     localparam DIRECT_PASSTHRU  = PASSTHRU && (`CS_WORD_SEL_BITS == 0) && (NUM_REQS == 1);
 
     localparam REQ_SEL_BITS     = `CLOG2(NUM_REQS);
+    localparam REQ_SEL_WIDTH    = `UP(REQ_SEL_BITS);
     localparam MUX_DATAW        = 1 + WORD_SIZE + CORE_ADDR_WIDTH + `MEM_REQ_FLAGS_WIDTH + CORE_DATA_WIDTH + CORE_TAG_WIDTH;
 
     localparam WORDS_PER_LINE   = LINE_SIZE / WORD_SIZE;
@@ -72,7 +73,7 @@ module VX_cache_bypass #(
     wire core_req_nc_valid;
     wire [NUM_REQS-1:0] core_req_nc_valids;
     wire [NUM_REQS-1:0] core_req_nc_idxs;
-    wire [`UP(REQ_SEL_BITS)-1:0] core_req_nc_idx;
+    wire [REQ_SEL_WIDTH-1:0] core_req_nc_idx;
     wire [NUM_REQS-1:0] core_req_nc_sel;
     wire core_req_nc_ready;
 
@@ -261,17 +262,15 @@ module VX_cache_bypass #(
         .data_out (mem_rsp_tag_id_nc)
     );
 
-    wire [`UP(REQ_SEL_BITS)-1:0] rsp_idx;
+    wire [REQ_SEL_WIDTH-1:0] rsp_idx;
     if (NUM_REQS > 1) begin
         assign rsp_idx = mem_rsp_tag_id_nc[(CORE_TAG_ID_BITS + WSEL_BITS) +: REQ_SEL_BITS];
     end else begin
         assign rsp_idx = 1'b0;
     end
 
-    wire [NUM_REQS-1:0] rsp_nc_valid = NUM_REQS'(is_mem_rsp_nc) << rsp_idx;
-
     for (genvar i = 0; i < NUM_REQS; ++i) begin
-        assign core_rsp_in_valid[i] = core_bus_out_if[i].rsp_valid || rsp_nc_valid[i];
+        assign core_rsp_in_valid[i] = core_bus_out_if[i].rsp_valid || (is_mem_rsp_nc && rsp_idx == REQ_SEL_WIDTH'(i));
         assign core_bus_out_if[i].rsp_ready = core_rsp_in_ready[i];
     end
 

diff --git a/hw/rtl/cache/VX_cache_data.sv b/hw/rtl/cache/VX_cache_data.sv
@@ -140,7 +140,7 @@ module VX_cache_data #(
         assign line_wren  = fill;
     end
 
-    VX_onehot_encoder #(
+    VX_encoder #(
         .N (NUM_WAYS)
     ) way_enc (
         .data_in  (way_sel),

diff --git a/hw/rtl/cache/VX_cache_mshr.sv b/hw/rtl/cache/VX_cache_mshr.sv
@@ -148,7 +148,7 @@ module VX_cache_mshr #(
         .valid_out (allocate_rdy_n)
     );
 
-    VX_onehot_encoder #(
+    VX_encoder #(
         .N (MSHR_SIZE)
     ) prev_sel (
         .data_in (addr_matches & ~next_table_x),

diff --git a/hw/rtl/libs/VX_cyclic_arbiter.sv b/hw/rtl/libs/VX_cyclic_arbiter.sv
@@ -41,7 +41,7 @@ module VX_cyclic_arbiter #(
         localparam IS_POW2 = (1 << LOG_NUM_REQS) == NUM_REQS;
 
         wire [LOG_NUM_REQS-1:0] grant_index_um;
-        wire [NUM_REQS-1:0] grant_onehot_um;
+        wire [NUM_REQS-1:0] grant_onehot_w, grant_onehot_um;
         reg [LOG_NUM_REQS-1:0] grant_index_r;
 
         always @(posedge clk) begin
@@ -65,10 +65,18 @@ module VX_cyclic_arbiter #(
             .valid_out  (grant_valid)
         );
 
+        VX_decoder #(
+            .N (LOG_NUM_REQS)
+        ) grant_decoder (
+            .shift_in (grant_index),
+            .data_in  (1'b1),
+            .data_out (grant_onehot_w)
+        );
+
         wire is_hit = requests[grant_index_r];
 
         assign grant_index  = is_hit ? grant_index_r : grant_index_um;
-        assign grant_onehot = is_hit ? (NUM_REQS'(1) << grant_index) : grant_onehot_um;
+        assign grant_onehot = is_hit ? grant_onehot_w : grant_onehot_um;
 
     end
 

diff --git a/hw/rtl/libs/VX_decoder.sv b/hw/rtl/libs/VX_decoder.sv
@@ -0,0 +1,46 @@
+// 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_platform.vh"
+
+// Fast encoder using parallel prefix computation
+// Adapted from BaseJump STL: http://bjump.org/data_out.html
+
+`TRACING_OFF
+module VX_decoder #(
+    parameter N = 1,
+    parameter M = 1,
+`ifdef VIVADO
+    parameter MODEL = 1,
+`else
+    parameter MODEL = 0,
+`endif
+    parameter D = 1 << N
+) (
+    input wire [N-1:0] shift_in,
+    input wire [M-1:0] data_in,
+    output wire [D-1:0][M-1:0] data_out
+);
+    if (MODEL == 1) begin
+        reg [D-1:0][M-1:0] data_out_w;
+        always @(*) begin
+            data_out_w = '0;
+            data_out_w[shift_in] = data_in;
+        end
+        assign data_out = data_out_w;
+    end else begin
+        assign data_out = (D*M)'(data_in) << (shift_in * M);
+    end
+
+endmodule
+`TRACING_ON
diff --git a/hw/rtl/libs/VX_onehot_encoder.sv → hw/rtl/libs/VX_encoder.sv b/hw/rtl/libs/VX_onehot_encoder.sv → hw/rtl/libs/VX_encoder.sv
@@ -17,7 +17,7 @@
 // Adapted from BaseJump STL: http://bjump.org/data_out.html
 
 `TRACING_OFF
-module VX_onehot_encoder #(
+module VX_encoder #(
     parameter N       = 1,
     parameter REVERSE = 0,
     parameter MODEL   = 1,

diff --git a/hw/rtl/libs/VX_matrix_arbiter.sv b/hw/rtl/libs/VX_matrix_arbiter.sv
@@ -74,7 +74,7 @@ module VX_matrix_arbiter #(
 
         assign grant_onehot = grant;
 
-        VX_onehot_encoder #(
+        VX_encoder #(
             .N (NUM_REQS)
         ) encoder (
             .data_in   (grant_onehot),

diff --git a/hw/rtl/libs/VX_mem_adapter.sv b/hw/rtl/libs/VX_mem_adapter.sv
@@ -97,10 +97,26 @@ module VX_mem_adapter #(
             assign mem_req_addr_out_w = mem_req_addr_in_qual;
         end
 
+        VX_decoder #(
+            .N (D),
+            .M (SRC_DATA_WIDTH/8)
+        ) req_be_dec (
+            .shift_in (req_idx),
+            .data_in  (mem_req_byteen_in),
+            .data_out (mem_req_byteen_out_w)
+        );
+
+        VX_decoder #(
+            .N (D),
+            .M (SRC_DATA_WIDTH)
+        ) req_data_dec (
+            .shift_in (req_idx),
+            .data_in  (mem_req_data_in),
+            .data_out (mem_req_data_out_w)
+        );
+
         assign mem_req_valid_out_w  = mem_req_valid_in;
         assign mem_req_rw_out_w     = mem_req_rw_in;
-        assign mem_req_byteen_out_w = DST_DATA_SIZE'(mem_req_byteen_in) << ((DST_LDATAW-3)'(req_idx) << (SRC_LDATAW-3));
-        assign mem_req_data_out_w   = DST_DATA_WIDTH'(mem_req_data_in) << ((DST_LDATAW'(req_idx)) << SRC_LDATAW);
         assign mem_req_tag_out_w    = DST_TAG_WIDTH'({mem_req_tag_in, req_idx});
         assign mem_req_ready_in     = mem_req_ready_out_w;
 

diff --git a/hw/rtl/libs/VX_rr_arbiter.sv b/hw/rtl/libs/VX_rr_arbiter.sv
@@ -448,7 +448,7 @@ module VX_rr_arbiter #(
 			end
 	    end
 
-        VX_onehot_encoder #(
+        VX_encoder #(
             .N (NUM_REQS)
         ) onehot_encoder (
             .data_in  (grant_onehot),
@@ -480,9 +480,16 @@ module VX_rr_arbiter #(
             end
         end
 
-        assign grant_index  = grant_table[state];
-        assign grant_onehot = NUM_REQS'(grant_valid) << grant_index;
-        assign grant_valid  = (| requests);
+        VX_decoder #(
+            .N (LOG_NUM_REQS)
+        ) grant_decoder (
+            .shift_in (grant_index),
+            .data_in  (grant_valid),
+            .data_out (grant_onehot)
+        );
+
+        assign grant_index = grant_table[state];
+        assign grant_valid = (| requests);
 
     end
 

diff --git a/hw/rtl/libs/VX_stream_xbar.sv b/hw/rtl/libs/VX_stream_xbar.sv
@@ -72,12 +72,17 @@ module VX_stream_xbar #(
             );
 
             for (genvar i = 0; i < NUM_INPUTS; ++i) begin
-                assign per_output_valid_in[i] = NUM_OUTPUTS'(valid_in[i]) << sel_in[i];
+                VX_decoder #(
+                    .N (OUT_WIDTH)
+                ) sel_in_decoder (
+                    .shift_in (sel_in[i]),
+                    .data_in  (valid_in[i]),
+                    .data_out (per_output_valid_in[i])
+                );
                 assign ready_in[i] = | per_output_ready_in_w[i];
             end
 
             for (genvar i = 0; i < NUM_OUTPUTS; ++i) begin
-
                 VX_stream_arb #(
                     .NUM_INPUTS  (NUM_INPUTS),
                     .NUM_OUTPUTS (1),
@@ -131,8 +136,15 @@ module VX_stream_xbar #(
         wire [NUM_OUTPUTS-1:0] valid_out_w, ready_out_w;
         wire [NUM_OUTPUTS-1:0][DATAW-1:0] data_out_w;
 
+        VX_decoder #(
+            .N (OUT_WIDTH)
+        ) sel_in_decoder (
+            .shift_in (sel_in[0]),
+            .data_in  (valid_in[0]),
+            .data_out (valid_out_w)
+        );
+
         assign ready_in[0] = ready_out_w[sel_in[0]];
-        assign valid_out_w = NUM_OUTPUTS'(valid_in[0]) << sel_in[0];
         assign data_out_w = {NUM_OUTPUTS{data_in[0]}};
 
         for (genvar i = 0; i < NUM_OUTPUTS; ++i) begin