From eee3bd279c21933c7932dd9ef81f4a6b40a52f1c Mon Sep 17 00:00:00 2001
From: Luigi Ghionda <luigi.ghionda2@unibo.it>
Date: Tue, 25 Jun 2024 17:45:33 +0200
Subject: [PATCH] Add pipe regs to cut critical paths

---
 rtl/tcdm_banks_wrap.sv | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/rtl/tcdm_banks_wrap.sv b/rtl/tcdm_banks_wrap.sv
index a11abfd..efca67f 100644
--- a/rtl/tcdm_banks_wrap.sv
+++ b/rtl/tcdm_banks_wrap.sv
@@ -61,6 +61,9 @@ for(genvar i=0; i<NbBanks; i++) begin : banks_gen
       localparam int unsigned AWS = HCI_MEM_SIZE.AW;
       localparam int unsigned UWS = HCI_MEM_SIZE.UW;
 
+      logic ecc_single_error_d, ecc_single_error_q;
+      logic ecc_multiple_error_d, ecc_multiple_error_q;
+
       // tie r_valid to '1, as HCI interconnect will generate this anyways
       assign tcdm_slave_dec.r_valid = '1;
 
@@ -85,18 +88,31 @@ for(genvar i=0; i<NbBanks; i++) begin : banks_gen
       );
 
       hci_ecc_dec #(
-        .DW                           ( DataWidth                   ),
-        .`HCI_SIZE_PARAM(tcdm_target) ( HCI_MEM_SIZE                ),
-        .EnableData                   ( 0                           )
+        .DW                           ( DataWidth    ),
+        .`HCI_SIZE_PARAM(tcdm_target) ( HCI_MEM_SIZE ),
+        .EnableData                   ( 0            )
       ) i_ecc_dec_meta (
         .data_single_err_o (  ),
         .data_multi_err_o  (  ),
-        .meta_single_err_o ( ecc_single_error_o[i] ),
-        .meta_multi_err_o  ( ecc_multiple_error_o[i] ),
-        .tcdm_target       ( tcdm_slave[i]     ),
-        .tcdm_initiator    ( tcdm_slave_dec )
+        .meta_single_err_o ( ecc_single_error_d   ),
+        .meta_multi_err_o  ( ecc_multiple_error_d ),
+        .tcdm_target       ( tcdm_slave[i]        ),
+        .tcdm_initiator    ( tcdm_slave_dec       )
       );
 
+      always_ff @(posedge clk_i or negedge rst_ni) begin : ecc_error_pipe
+        if(~rst_ni) begin
+          ecc_single_error_q   <= '0;
+          ecc_multiple_error_q <= '0;
+        end else begin
+          ecc_single_error_q   <= ecc_single_error_d;
+          ecc_multiple_error_q <= ecc_multiple_error_d;
+        end
+      end
+
+      assign ecc_single_error_o[i] = ecc_single_error_q;
+      assign ecc_multiple_error_o[i] = ecc_multiple_error_q;
+
       // ecc_sram_wrap assumes a 32-bit address
       logic [31:0] tcdm_slave_dec_add_unroll;
       assign tcdm_slave_dec_add_unroll = 32'b0 | tcdm_slave_dec.add;