rfnoc: add rx and tx transports, and amend rfnoc_graph

transports:

Transports build on I/O service and implements flow control and
sequence number checking.

The rx streamer subclass extends the streamer implementation to connect
it to the rfnoc graph. It receives configuration values from property
propagation and configures the streamer accordingly. It also implements
the issue_stream_cmd rx_streamer API method.

Add implementation of rx streamer creation and method to connect it to
an rfnoc block.

rfnoc_graph: Cache more connection info, clarify contract

Summary of changes:
- rfnoc_graph stores more information about static connections at the
  beginning. Some search algorithms are replaced by simpler lookups.
- The contract for connect() was clarified. It is required to call
  connect, even for static connections.

1 files changed, 141 insertions, 0 deletions

diff --git a/host/lib/rfnoc/rfnoc_rx_streamer.cpp b/host/lib/rfnoc/rfnoc_rx_streamer.cpp
new file mode 100644
index 000000000..4340faff0
--- /dev/null
+++ b/host/lib/rfnoc/rfnoc_rx_streamer.cpp
@@ -0,0 +1,141 @@
+//
+// Copyright 2019 Ettus Research, a National Instruments Brand
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+
+#include <uhd/rfnoc/defaults.hpp>
+#include <uhdlib/rfnoc/node_accessor.hpp>
+#include <uhdlib/rfnoc/rfnoc_rx_streamer.hpp>
+#include <atomic>
+
+using namespace uhd;
+using namespace uhd::rfnoc;
+
+const std::string STREAMER_ID = "RxStreamer";
+static std::atomic<uint64_t> streamer_inst_ctr;
+
+rfnoc_rx_streamer::rfnoc_rx_streamer(const size_t num_chans,
+    const uhd::stream_args_t stream_args)
+    : rx_streamer_impl<chdr_rx_data_xport>(num_chans, stream_args)
+    , _unique_id(STREAMER_ID + "#" + std::to_string(streamer_inst_ctr++))
+    , _stream_args(stream_args)
+{
+    // No block to which to forward properties or actions
+    set_prop_forwarding_policy(forwarding_policy_t::DROP);
+    set_action_forwarding_policy(forwarding_policy_t::DROP);
+
+    // Initialize properties
+    _scaling_in.reserve(num_chans);
+    _samp_rate_in.reserve(num_chans);
+    _tick_rate_in.reserve(num_chans);
+    _type_in.reserve(num_chans);
+
+    for (size_t i = 0; i < num_chans; i++) {
+        _register_props(i, stream_args.otw_format);
+    }
+    node_accessor_t node_accessor{};
+    node_accessor.init_props(this);
+}
+
+std::string rfnoc_rx_streamer::get_unique_id() const
+{
+    return _unique_id;
+}
+
+size_t rfnoc_rx_streamer::get_num_input_ports() const
+{
+    return get_num_channels();
+}
+
+size_t rfnoc_rx_streamer::get_num_output_ports() const
+{
+    return 0;
+}
+
+void rfnoc_rx_streamer::issue_stream_cmd(const stream_cmd_t& stream_cmd)
+{
+    if (get_num_channels() > 1 and stream_cmd.stream_now
+        and stream_cmd.stream_mode != stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS) {
+        throw uhd::runtime_error(
+            "Invalid recv stream command - stream now on multiple channels in a "
+            "single streamer will fail to time align.");
+    }
+
+    auto cmd = stream_cmd_action_info::make(stream_cmd.stream_mode);
+    cmd->stream_cmd = stream_cmd;
+
+    for (size_t i = 0; i < get_num_channels(); i++) {
+        const res_source_info info(res_source_info::INPUT_EDGE, i);
+        post_action(info, cmd);
+    }
+}
+
+const uhd::stream_args_t& rfnoc_rx_streamer::get_stream_args() const
+{
+    return _stream_args;
+}
+
+bool rfnoc_rx_streamer::check_topology(
+    const std::vector<size_t>& connected_inputs,
+    const std::vector<size_t>& connected_outputs)
+{
+    // Check that all channels are connected
+    if (connected_inputs.size() != get_num_input_ports()) {
+        return false;
+    }
+
+    // Call base class to check that connections are valid
+    return node_t::check_topology(connected_inputs, connected_outputs);
+}
+
+void rfnoc_rx_streamer::_register_props(const size_t chan,
+    const std::string& otw_format)
+{
+    // Create actual properties and store them
+    _scaling_in.push_back(property_t<double>(
+        PROP_KEY_SCALING, {res_source_info::INPUT_EDGE, chan}));
+    _samp_rate_in.push_back(
+        property_t<double>(PROP_KEY_SAMP_RATE, {res_source_info::INPUT_EDGE, chan}));
+    _tick_rate_in.push_back(property_t<double>(
+        PROP_KEY_TICK_RATE, {res_source_info::INPUT_EDGE, chan}));
+    _type_in.emplace_back(property_t<std::string>(
+        PROP_KEY_TYPE, otw_format, {res_source_info::INPUT_EDGE, chan}));
+
+    // Give us some shorthands for the rest of this function
+    property_t<double>* scaling_in   = &_scaling_in.back();
+    property_t<double>* samp_rate_in = &_samp_rate_in.back();
+    property_t<double>* tick_rate_in = &_tick_rate_in.back();
+    property_t<std::string>* type_in = &_type_in.back();
+
+    // Register them
+    register_property(scaling_in);
+    register_property(samp_rate_in);
+    register_property(tick_rate_in);
+    register_property(type_in);
+
+    // Add resolvers
+    add_property_resolver({scaling_in}, {},
+        [&scaling_in = *scaling_in, chan, this]() {
+            RFNOC_LOG_TRACE("Calling resolver for `scaling_in'@" << chan);
+            if (scaling_in.is_valid()) {
+                this->set_scale_factor(chan, scaling_in.get() / 32767.0);
+            }
+        });
+
+    add_property_resolver({samp_rate_in}, {},
+        [&samp_rate_in = *samp_rate_in, chan, this]() {
+            RFNOC_LOG_TRACE("Calling resolver for `samp_rate_in'@" << chan);
+            if (samp_rate_in.is_valid()) {
+                this->set_samp_rate(samp_rate_in.get());
+            }
+        });
+
+    add_property_resolver({tick_rate_in}, {},
+        [&tick_rate_in = *tick_rate_in, chan, this]() {
+            RFNOC_LOG_TRACE("Calling resolver for `tick_rate_in'@" << chan);
+            if (tick_rate_in.is_valid()) {
+                this->set_tick_rate(tick_rate_in.get());
+            }
+        });
+}