rfnoc: lib: introduce ctrl-port interface and BFM

Original-commit: 886cf97ad5d494b20c6fff0a53113f6096d458c7

lib/rfnoc/utils/ctrlport_if_clk_cross.sv

@@ -0,0 +1,84 @@
+//
+// Copyright 2025 Ettus Research, a National Instruments Brand
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+//
+// Module: ctrlport_if_clk_cross
+//
+// Description:
+//
+//   Crosses control-port interface between different clock domains.
+//
+
+
+module ctrlport_if_clk_cross
+(
+  ctrlport_if.slave s_ctrlport,
+  ctrlport_if.master m_ctrlport
+
+);
+  import ctrlport_pkg::*;
+
+  //---------------------------------------------------------------------------
+  // Slave to Master Clock Crossing (Request)
+  //---------------------------------------------------------------------------
+  ctrlport_request_t m_req_hs;
+  logic              m_req_hs_valid;
+
+  // Busy flag can be ignored as the response handshake takes at least the same
+  // amount of cycles to transfer the response as this handshake instance needs
+  // to release the busy flag as they are configured with the same amount of
+  // synchronization stages. Furthermore the ctrlport protocol just allows for
+  // one transaction to be active at the same time. A request can only be issued
+  // once the response is provided.
+  handshake #(
+    .WIDTH($bits(ctrlport_request_t))
+  ) req_handshake_inst (
+    .clk_a(s_ctrlport.clk),
+    .rst_a(s_ctrlport.rst),
+    .valid_a((s_ctrlport.req.rd | s_ctrlport.req.wr) & ~s_ctrlport.rst),
+    .data_a(s_ctrlport.req),
+    .busy_a(),
+    .clk_b(m_ctrlport.clk),
+    .valid_b(m_req_hs_valid),
+    .data_b(m_req_hs)
+  );
+
+  always_comb begin
+    m_ctrlport.req = m_req_hs;
+    // mask read and write flags
+    m_ctrlport.req.wr = m_req_hs.wr & m_req_hs_valid & ~m_ctrlport.rst;
+    m_ctrlport.req.rd = m_req_hs.rd & m_req_hs_valid & ~m_ctrlport.rst;
+  end
+
+  //---------------------------------------------------------------------------
+  // Master to Slave Clock Crossing (Response)
+  //---------------------------------------------------------------------------
+  ctrlport_response_t s_resp_hs;
+  logic               s_resp_hs_valid;
+
+  // Busy flag can be ignored as the request handshake takes at least the same
+  // amount of cycles to transfer the request as this handshake instance needs
+  // to release the busy flag as they are configured with the same amount of
+  // synchronization stages. Furthermore the ctrlport protocol just allows for
+  // one transaction to be active at the same time. A response can only be
+  // issued once the request is available.
+  handshake #(
+    .WIDTH($bits(ctrlport_response_t))
+  ) resp_handshake_inst (
+    .clk_a(m_ctrlport.clk),
+    .rst_a(m_ctrlport.rst),
+    .valid_a(m_ctrlport.resp.ack & ~m_ctrlport.rst),
+    .data_a(m_ctrlport.resp),
+    .busy_a(),
+    .clk_b(s_ctrlport.clk),
+    .valid_b(s_resp_hs_valid),
+    .data_b(s_resp_hs)
+  );
+
+  always_comb begin
+    s_ctrlport.resp = s_resp_hs;
+    s_ctrlport.resp.ack = s_resp_hs.ack & s_resp_hs_valid & ~s_ctrlport.rst;
+  end
+
+endmodule