rfnoc: radio/streamer: Handle late commands and burst ACKs

- Burst ACKs are already handled by the TX streamer, but the radio now
  also sends an action upstream on reception of a burst ACK
- Late commands were only acquitted by an 'L', now an action gets sent
  downstream and is handled in the rx streamer

5 files changed, 52 insertions, 7 deletions

diff --git a/host/lib/include/uhdlib/rfnoc/radio_control_impl.hpp b/host/lib/include/uhdlib/rfnoc/radio_control_impl.hpp
index 5327105c8..fc0d19a0a 100644
--- a/host/lib/include/uhdlib/rfnoc/radio_control_impl.hpp
+++ b/host/lib/include/uhdlib/rfnoc/radio_control_impl.hpp
@@ -241,13 +241,16 @@ public:
 
     struct err_codes
     {
-        static const uint32_t ERR_RX_LATE_CMD =
-            1; // Late command (arrived after indicated time)
-        static const uint32_t ERR_RX_OVERRUN = 2; // FIFO overflow
-        static const uint32_t ERR_TX_UNDERRUN =
-            1; // Data underflow (data not available when needed)
-        static const uint32_t ERR_TX_LATE_DATA =
-            2; // Late data (arrived after indicated time)
+        //! Late command (stream command arrived after indicated time)
+        static const uint32_t ERR_RX_LATE_CMD = 1;
+        //! FIFO overflow
+        static const uint32_t ERR_RX_OVERRUN = 2;
+        // FIFO underrun (data not available when needed)
+        static const uint32_t ERR_TX_UNDERRUN = 1;
+        //! Late data (arrived after indicated time)
+        static const uint32_t ERR_TX_LATE_DATA = 2;
+        //! Acknowledge a TX burst with an EOB
+        static const uint32_t EVENT_TX_BURST_ACK = 3;
     };
 
     //! Tree path to the dboard-specific properties
diff --git a/host/lib/include/uhdlib/transport/rx_streamer_impl.hpp b/host/lib/include/uhdlib/transport/rx_streamer_impl.hpp
index b52358e55..c57a8e0d1 100644
--- a/host/lib/include/uhdlib/transport/rx_streamer_impl.hpp
+++ b/host/lib/include/uhdlib/transport/rx_streamer_impl.hpp
@@ -220,6 +220,12 @@ protected:
         _zero_copy_streamer.set_stopped_due_to_overrun();
     }
 
+    //! Notifies the streamer that an overrun has occured
+    void set_stopped_due_to_late_command()
+    {
+        _zero_copy_streamer.set_stopped_due_to_late_command();
+    }
+
     //! Provides a callback to handle overruns
     void set_overrun_handler(
         typename rx_streamer_zero_copy<transport_t>::overrun_handler_t handler)
diff --git a/host/lib/include/uhdlib/transport/rx_streamer_zero_copy.hpp b/host/lib/include/uhdlib/transport/rx_streamer_zero_copy.hpp
index 1f7320330..27b7eaf7d 100644
--- a/host/lib/include/uhdlib/transport/rx_streamer_zero_copy.hpp
+++ b/host/lib/include/uhdlib/transport/rx_streamer_zero_copy.hpp
@@ -93,6 +93,12 @@ public:
         _stopped_due_to_overrun = true;
     }
 
+    //! Notifies the streamer that a late command has occured
+    void set_stopped_due_to_late_command()
+    {
+        _stopped_due_to_late_cmd = true;
+    }
+
     //! Provides a callback to handle overruns
     void set_overrun_handler(overrun_handler_t handler)
     {
@@ -161,6 +167,12 @@ public:
                 // Packets were not available with zero timeout, wait for them
                 // to arrive using the specified timeout.
                 result = _get_aligned_buffs(timeout_ms);
+                if (_stopped_due_to_late_cmd) {
+                    metadata.has_time_spec   = false;
+                    metadata.error_code      = rx_metadata_t::ERROR_CODE_LATE_COMMAND;
+                    _stopped_due_to_late_cmd = false;
+                    return 0;
+                }
             }
         }
 
@@ -285,6 +297,10 @@ private:
     // overrun error when no more packets are available.
     std::atomic<bool> _stopped_due_to_overrun{false};
 
+    // Flag that indicates a late command occurred. The streamer will return a
+    // late command error when no more packets are available.
+    std::atomic<bool> _stopped_due_to_late_cmd{false};
+
     // Callback for overrun
     overrun_handler_t _overrun_handler;
 };
diff --git a/host/lib/rfnoc/radio_control_impl.cpp b/host/lib/rfnoc/radio_control_impl.cpp
index e400033b3..2a730e8df 100644
--- a/host/lib/rfnoc/radio_control_impl.cpp
+++ b/host/lib/rfnoc/radio_control_impl.cpp
@@ -872,6 +872,8 @@ bool radio_control_impl::async_message_validator(
                 return true;
             case err_codes::ERR_TX_LATE_DATA:
                 return true;
+            case err_codes::EVENT_TX_BURST_ACK:
+                return true;
             default:
                 return false;
         }
@@ -939,6 +941,14 @@ void radio_control_impl::async_message_handler(
                     RFNOC_LOG_TRACE("Posting late data event action message.");
                     break;
                 }
+                case err_codes::EVENT_TX_BURST_ACK: {
+                    auto tx_event_action = tx_event_action_info::make(
+                        uhd::async_metadata_t::EVENT_CODE_BURST_ACK);
+                    post_action(res_source_info{res_source_info::INPUT_EDGE, chan},
+                        tx_event_action);
+                    RFNOC_LOG_TRACE("Posting burst ack event action message.");
+                    break;
+                }
             }
             break;
         }
@@ -963,6 +973,12 @@ void radio_control_impl::async_message_handler(
                 }
                 case err_codes::ERR_RX_LATE_CMD:
                     UHD_LOG_FASTPATH("L");
+                    auto rx_event_action = rx_event_action_info::make();
+                    rx_event_action->error_code =
+                        uhd::rx_metadata_t::ERROR_CODE_LATE_COMMAND;
+                    RFNOC_LOG_TRACE("Posting RX late command message.");
+                    post_action(res_source_info{res_source_info::OUTPUT_EDGE, chan},
+                        rx_event_action);
                     break;
             }
             break;
diff --git a/host/lib/rfnoc/rfnoc_rx_streamer.cpp b/host/lib/rfnoc/rfnoc_rx_streamer.cpp
index 9383e3487..d6778267f 100644
--- a/host/lib/rfnoc/rfnoc_rx_streamer.cpp
+++ b/host/lib/rfnoc/rfnoc_rx_streamer.cpp
@@ -244,6 +244,10 @@ void rfnoc_rx_streamer::_handle_rx_event_action(
         // Tell the streamer to flag an overrun to the user after the data that
         // was buffered prior to the overrun is read.
         set_stopped_due_to_overrun();
+    } else if (rx_event_action->error_code
+               == uhd::rx_metadata_t::ERROR_CODE_LATE_COMMAND) {
+        RFNOC_LOG_DEBUG("Received late command message on port " << src.instance);
+        set_stopped_due_to_late_command();
     }
 }