ue: remove stack type parameter

for the moment we always use the LTE stack (also for NSA mode).
For SA we likely pick a smarter approach to pick the stack type, i.e.
using the ARFCN specified in the config.

srsue/hdr/stack/ue_stack_base.h

@@ -56,7 +56,6 @@ typedef struct {
 } stack_log_args_t;
 
 typedef struct {
-  std::string      type;
   pkt_trace_args_t pkt_trace;
   stack_log_args_t log;
   usim_args_t      usim;

srsue/src/main.cc

@@ -67,7 +67,6 @@ static int parse_args(all_args_t* args, int argc, char* argv[])
   common.add_options()
     ("ue.radio", bpo::value<string>(&args->rf.type)->default_value("multi"), "Type of the radio [multi]")
     ("ue.phy", bpo::value<string>(&args->phy.type)->default_value("lte"), "Type of the PHY [lte]")
-    ("ue.stack", bpo::value<string>(&args->stack.type)->default_value("lte"), "Type of the upper stack [lte, nr]")
 
     ("rf.srate",        bpo::value<double>(&args->rf.srate_hz)->default_value(0.0),          "Force Tx and Rx sampling rate in Hz")
     ("rf.freq_offset",  bpo::value<float>(&args->rf.freq_offset)->default_value(0),          "(optional) Frequency offset")

srsue/src/test/ttcn3/src/ttcn3_ue.cc

@@ -50,11 +50,9 @@ int ttcn3_ue::init(all_args_t args, syssim_interface_phy* syssim_, const std::st
 
   args.phy.dl_earfcn = "3400";
   args.rf.type       = "none";
-  args.stack.type    = "lte";
   args.phy.type      = "lte_ttcn3";
 
   // Instantiate layers and stack together our UE
-  if (args.stack.type == "lte") {
   stack = std::unique_ptr<ue_stack_lte>(new ue_stack_lte);
   if (!stack) {
     srsran::console("Error creating LTE stack instance.\n");
@@ -66,10 +64,6 @@ int ttcn3_ue::init(all_args_t args, syssim_interface_phy* syssim_, const std::st
     srsran::console("Error creating LTE PHY instance.\n");
     return SRSRAN_ERROR;
   }
-  } else {
-    srsran::console("Invalid stack type %s. Supported values are [lte].\n", args.stack.type.c_str());
-    return SRSRAN_ERROR;
-  }
 
   // init layers
   if (phy->init(args.phy, stack.get(), syssim_)) {

srsue/src/ue.cc

@@ -54,7 +54,6 @@ int ue::init(const all_args_t& args_)
   }
 
   // Instantiate layers and stack together our UE
-  if (args.stack.type == "lte") {
   std::unique_ptr<ue_stack_lte> lte_stack(new ue_stack_lte);
   if (!lte_stack) {
     srsran::console("Error creating LTE stack instance.\n");
@@ -119,43 +118,6 @@ int ue::init(const all_args_t& args_)
   gw_inst = std::move(gw_ptr);
   phy     = std::move(lte_phy);
   radio   = std::move(lte_radio);
-  } else if (args.stack.type == "nr") {
-    logger.info("Initializing NR stack");
-    std::unique_ptr<srsue::ue_stack_nr> nr_stack(new srsue::ue_stack_nr());
-    std::unique_ptr<srsran::radio_null> nr_radio(new srsran::radio_null);
-    std::unique_ptr<srsue::ue_phy_base> nr_phy;
-    std::unique_ptr<gw>                 gw_ptr(new gw(srslog::fetch_basic_logger("GW")));
-
-    // Init layers
-    if (nr_radio->init(args.rf, nullptr)) {
-      srsran::console("Error initializing radio.\n");
-      return SRSRAN_ERROR;
-    }
-
-    if (nr_phy->init(args.phy)) {
-      srsran::console("Error initializing PHY.\n");
-      return SRSRAN_ERROR;
-    }
-
-    if (nr_stack->init(args.stack)) {
-      srsran::console("Error initializing stack.\n");
-      return SRSRAN_ERROR;
-    }
-
-    if (gw_ptr->init(args.gw, nr_stack.get())) {
-      srsran::console("Error initializing GW.\n");
-      return SRSRAN_ERROR;
-    }
-
-    // move ownership
-    stack   = std::move(nr_stack);
-    gw_inst = std::move(gw_ptr);
-    phy     = std::move(nr_phy);
-    radio   = std::move(nr_radio);
-  } else {
-    srsran::console("Invalid stack type %s. Supported values are [lte].\n", args.stack.type.c_str());
-    ret = SRSRAN_ERROR;
-  }
 
   if (phy) {
     srsran::console("Waiting PHY to initialize ... ");