uhd: added async recv message call to device api

implemented in usrp2 io impl

added async metadata type

2 files changed, 36 insertions, 5 deletions

diff --git a/host/lib/usrp/usrp2/io_impl.cpp b/host/lib/usrp/usrp2/io_impl.cpp
index 1947fdf00..455a30b47 100644
--- a/host/lib/usrp/usrp2/io_impl.cpp
+++ b/host/lib/usrp/usrp2/io_impl.cpp
@@ -44,7 +44,8 @@ struct usrp2_impl::io_impl{
 
     io_impl(size_t num_frames, size_t width):
         packet_handler_recv_state(width),
-        recv_pirate_booty(alignment_buffer_type::make(num_frames, width))
+        recv_pirate_booty(alignment_buffer_type::make(num_frames, width)),
+        async_msg_fifo(bounded_buffer<async_metadata_t>::make(100/*messages deep*/))
     {
         /* NOP */
     }
@@ -69,6 +70,7 @@ struct usrp2_impl::io_impl{
     boost::thread_group recv_pirate_crew;
     bool recv_pirate_crew_raiding;
     alignment_buffer_type::sptr recv_pirate_booty;
+    bounded_buffer<async_metadata_t>::sptr async_msg_fifo;
     size_t recv_timeout_ms;
 };
 
@@ -94,18 +96,34 @@ void usrp2_impl::io_impl::recv_pirate_loop(
             //extract the vrt header packet info
             vrt::if_packet_info_t if_packet_info;
             if_packet_info.num_packet_words32 = buff->size()/sizeof(boost::uint32_t);
-            vrt::if_hdr_unpack_be(buff->cast<const boost::uint32_t *>(), if_packet_info);
+            const boost::uint32_t *vrt_hdr = buff->cast<const boost::uint32_t *>();
+            vrt::if_hdr_unpack_be(vrt_hdr, if_packet_info);
 
-            //handle a tx async report message (TODO forward info)
+            //handle a tx async report message
             if (if_packet_info.sid == 1 and if_packet_info.packet_type != vrt::if_packet_info_t::PACKET_TYPE_DATA){
-                std::cerr << "U";
+                const boost::uint32_t *vrt_data = vrt_hdr + if_packet_info.num_header_words32;
+                //extract the context word (we dont know the endianness so mirror the bytes)
+                boost::uint32_t word0 = vrt_data[0] | uhd::byteswap(vrt_data[0]);
+
+                //fill in the async metadata
+                async_metadata_t metadata;
+                metadata.channel = index;
+                metadata.has_time_spec = if_packet_info.has_tsi and if_packet_info.has_tsf;
+                metadata.time_spec = time_spec_t(
+                    time_t(if_packet_info.tsi), size_t(if_packet_info.tsf), mboard->get_master_clock_freq()
+                );
+                metadata.event_code = uhd::async_metadata_t::event_code_t(word0 & 0xf);
+
+                //print the famous U, and push the metadata into the message queue
+                if (metadata.event_code == async_metadata_t::EVENT_CODE_UNDERFLOW) std::cerr << "U";
+                async_msg_fifo->push_with_pop_on_full(metadata);
                 continue;
             }
 
             //handle the packet count / sequence number
             if (if_packet_info.packet_count != next_packet_seq){
                 //std::cerr << "S" << (if_packet_info.packet_count - next_packet_seq)%16;
-                std::cerr << "O"; //report overrun (drops in the kernel)
+                std::cerr << "O"; //report overflow (drops in the kernel)
             }
             next_packet_seq = (if_packet_info.packet_count+1)%16;
 
@@ -157,6 +175,18 @@ void usrp2_impl::io_init(void){
 }
 
 /***********************************************************************
+ * Async Data
+ **********************************************************************/
+bool usrp2_impl::recv_async_msg(
+    async_metadata_t &async_metadata, size_t timeout_ms
+){
+    boost::this_thread::disable_interruption di; //disable because the wait can throw
+    return _io_impl->async_msg_fifo->pop_with_timed_wait(
+        async_metadata, boost::posix_time::milliseconds(timeout_ms)
+    );
+}
+
+/***********************************************************************
  * Send Data
  **********************************************************************/
 bool get_send_buffs(
diff --git a/host/lib/usrp/usrp2/usrp2_impl.hpp b/host/lib/usrp/usrp2/usrp2_impl.hpp
index cae1b21d6..2eaf12350 100644
--- a/host/lib/usrp/usrp2/usrp2_impl.hpp
+++ b/host/lib/usrp/usrp2/usrp2_impl.hpp
@@ -235,6 +235,7 @@ public:
         uhd::rx_metadata_t &, const uhd::io_type_t &,
         uhd::device::recv_mode_t, size_t
     );
+    bool recv_async_msg(uhd::async_metadata_t &, size_t);
 
 private:
     //device properties interface