From 8b2b2d7211803ab69562c40fa35770647bd56e68 Mon Sep 17 00:00:00 2001 From: Riccardo Tedeschi <58978462+ricted98@users.noreply.github.com> Date: Tue, 24 Sep 2024 08:42:16 +0200 Subject: [PATCH] Add AW lock register to handle W FIFO push signal (#2461) Signed-off-by: Nils Wistoff --- core/cache_subsystem/std_cache_subsystem.sv | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/core/cache_subsystem/std_cache_subsystem.sv b/core/cache_subsystem/std_cache_subsystem.sv index 3695e50c23..b91a6dc965 100644 --- a/core/cache_subsystem/std_cache_subsystem.sv +++ b/core/cache_subsystem/std_cache_subsystem.sv @@ -133,6 +133,8 @@ module std_cache_subsystem logic [1:0] w_select, w_select_fifo, w_select_arbiter; logic [1:0] w_fifo_usage; logic w_fifo_empty, w_fifo_full; + logic w_fifo_push, w_fifo_pop; + logic aw_lock_q, aw_lock_d; // AR Channel @@ -188,17 +190,26 @@ module std_cache_subsystem .flush_i (1'b0), .testmode_i(1'b0), .full_o (w_fifo_full), - .empty_o (), // leave open + .empty_o (), // leave open .usage_o (w_fifo_usage), .data_i (w_select), // a new transaction was requested and granted - .push_i (axi_req_o.aw_valid & axi_resp_i.aw_ready), + .push_i (w_fifo_push), // write ID to select the output MUX .data_o (w_select_fifo), // transaction has finished - .pop_i (axi_req_o.w_valid & axi_resp_i.w_ready & axi_req_o.w.last) + .pop_i (w_fifo_pop) ); + always_ff @(posedge clk_i or negedge rst_ni) begin : aw_lock_reg + if (~rst_ni) aw_lock_q <= 1'b0; + else aw_lock_q <= aw_lock_d; + end + + assign w_fifo_push = ~aw_lock_q & axi_req_o.aw_valid; + assign w_fifo_pop = axi_req_o.w_valid & axi_resp_i.w_ready & axi_req_o.w.last; + assign aw_lock_d = ~axi_resp_i.aw_ready & (axi_req_o.aw_valid | aw_lock_q); + // In fall-through mode, the empty_o will be low when push_i is high (on zero usage). // We do not want this here. Also, usage_o is missing the MSB, so on full fifo, usage_o is zero. assign w_fifo_empty = w_fifo_usage == 0 && !w_fifo_full;