stats: Add statistics collector module and testbench

Signed-off-by: Alex Forencich <alex@alexforencich.com>

tb/stats/taxi_stats_collect/test_taxi_stats_collect.sv

@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: CERN-OHL-S-2.0
+/*
+
+Copyright (c) 2025 FPGA Ninja, LLC
+
+Authors:
+- Alex Forencich
+
+*/
+
+`resetall
+`timescale 1ns / 1ps
+`default_nettype none
+
+/*
+ * Statistics collector testbench
+ */
+module test_taxi_stats_collect #
+(
+    /* verilator lint_off WIDTHTRUNC */
+    parameter CNT = 8,
+    parameter INC_W = 8,
+    parameter ID_BASE = 0,
+    parameter UPDATE_PERIOD = 128,
+    parameter STAT_INC_W = 16,
+    parameter STAT_ID_W = $clog2(CNT)
+    /* verilator lint_on WIDTHTRUNC */
+)
+();
+
+logic clk;
+logic rst;
+
+logic [INC_W-1:0] stat_inc[CNT];
+logic [0:0] stat_valid[CNT];
+
+taxi_axis_if #(
+    .DATA_W(STAT_INC_W),
+    .KEEP_EN(0),
+    .KEEP_W(1),
+    .ID_EN(1),
+    .ID_W(STAT_ID_W)
+) m_axis_stat();
+
+logic update;
+
+taxi_stats_collect #(
+    .CNT(CNT),
+    .INC_W(INC_W),
+    .ID_BASE(ID_BASE),
+    .UPDATE_PERIOD(UPDATE_PERIOD)
+)
+uut (
+    .clk(clk),
+    .rst(rst),
+
+    /*
+     * Increment inputs
+     */
+    .stat_inc(stat_inc),
+    .stat_valid(stat_valid),
+
+    /*
+     * Statistics increment output
+     */
+    .m_axis_stat(m_axis_stat),
+
+    /*
+     * Control inputs
+     */
+    .update(update)
+);
+
+endmodule
+
+`resetall