rfnoc: tick_node: Search all nodes for tick rates

The tick_node was trying to find the current tick rate by only querying
active blocks (i.e., blocks that were flagged active-streaming).
However, this is not necessary since we require all blocks to run at the
same tick rate.
In theory, querying active-only ports should be fine, but due to some
idiosyncrasies in our current graph code, connecting a single streamer
to channel 1 (out of 0, 1) would try and get the info from the wrong
port. This is not a fix to the graph code, but the change to tick_node
is also appropriate and is sufficient to fix the "late packets on
channel 1" issue.

This issue would manifest when sending timed packats to channel 1 in
a single-channel streamer. The problem is that it wouldn't be able to
read the correct tick rate.

1 files changed, 5 insertions, 3 deletions

diff --git a/host/lib/rfnoc/tick_node_ctrl.cpp b/host/lib/rfnoc/tick_node_ctrl.cpp
index 84edd92db..40131e72f 100644
--- a/host/lib/rfnoc/tick_node_ctrl.cpp
+++ b/host/lib/rfnoc/tick_node_ctrl.cpp
@@ -26,12 +26,14 @@ double tick_node_ctrl::get_tick_rate(
     // This will fail if we get different values.
     std::set<node_ctrl_base::sptr> explored_nodes(_explored_nodes);
     explored_nodes.insert(shared_from_this());
-    // Here, we need all up- and downstream nodes
+    // Here, we need all up- and downstream nodes. Note that we have the rule
+    // that there can only be one tick rate in all of the nodes, that means we
+    // don't only search active neighbouring nodes.
     std::vector<sptr> neighbouring_tick_nodes =
-        find_downstream_node<tick_node_ctrl>(true);
+        find_downstream_node<tick_node_ctrl>(false);
     {
         std::vector<sptr> upstream_neighbouring_tick_nodes =
-            find_upstream_node<tick_node_ctrl>(true);
+            find_upstream_node<tick_node_ctrl>(false);
         neighbouring_tick_nodes.insert(neighbouring_tick_nodes.end(),
             upstream_neighbouring_tick_nodes.begin(),
             upstream_neighbouring_tick_nodes.end());