rfnoc: Add post_init() method to noc_block_base

This method allows running a fixed set of rules to check the internal
consistency of a block. This may be necessary, because blocks authors
may incorrectly implement a certain design rule, and we want the ability
to not start an RFNoC graph with blocks that have rule violations which
we can write checks for.

3 files changed, 34 insertions, 0 deletions

diff --git a/host/include/uhd/rfnoc/noc_block_base.hpp b/host/include/uhd/rfnoc/noc_block_base.hpp
index b9ebda63b..b18de41fc 100644
--- a/host/include/uhd/rfnoc/noc_block_base.hpp
+++ b/host/include/uhd/rfnoc/noc_block_base.hpp
@@ -311,6 +311,8 @@ protected:
     virtual void deinit();
 
 private:
+    friend struct block_initializer;
+
     /*! Update the tick rate of this block
      *
      * This will make sure that the underlying register_iface is notified of the
@@ -325,6 +327,15 @@ private:
      */
     void shutdown() override;
 
+    /*! Run post-init tasks, i.e., after the constructor concludes.
+     *
+     * The purpose of this method is to make sure the block is in a good state
+     * after the block controller's ctor has concluded. This allows checking
+     * that block configurations follow certain rules, even though they may not
+     * even be part of UHD.
+     */
+    void post_init();
+
     /**************************************************************************
      * Attributes
      **************************************************************************/
diff --git a/host/lib/rfnoc/noc_block_base.cpp b/host/lib/rfnoc/noc_block_base.cpp
index 9719e739b..f854ca8d4 100644
--- a/host/lib/rfnoc/noc_block_base.cpp
+++ b/host/lib/rfnoc/noc_block_base.cpp
@@ -350,6 +350,11 @@ void noc_block_base::shutdown()
     update_reg_iface();
 }
 
+void noc_block_base::post_init()
+{
+    // nop
+}
+
 std::shared_ptr<mb_controller> noc_block_base::get_mb_controller()
 {
     return _mb_controller;
diff --git a/host/lib/rfnoc/rfnoc_graph.cpp b/host/lib/rfnoc/rfnoc_graph.cpp
index 35a5cb28c..0d0e03043 100644
--- a/host/lib/rfnoc/rfnoc_graph.cpp
+++ b/host/lib/rfnoc/rfnoc_graph.cpp
@@ -58,8 +58,25 @@ struct route_info_t
     graph_edge_t src_static_edge;
     graph_edge_t dst_static_edge;
 };
+
 } // namespace
 
+// Define an attorney to limit access to noc_block_base internals
+class rfnoc_graph_impl;
+namespace uhd { namespace rfnoc {
+
+class block_initializer
+{
+    static void post_init(noc_block_base::sptr block)
+    {
+        block->post_init();
+    }
+    friend rfnoc_graph_impl;
+};
+
+}} // namespace uhd::rfnoc
+
+
 class rfnoc_graph_impl : public rfnoc_graph
 {
 public:
@@ -731,6 +748,7 @@ private:
             try {
                 _block_registry->register_block(
                     block_factory_info.factory_fn(std::move(make_args_uptr)));
+                block_initializer::post_init(_block_registry->get_block(block_id));
             } catch (...) {
                 UHD_LOG_ERROR(
                     LOG_ID, "Error during initialization of block " << block_id << "!");