signaling RRC RA problems (leading to possible radio link failure)

openair1/SIMULATION/NR_PHY/nr_dummy_functions.c

@@ -36,7 +36,7 @@ void nr_mac_rrc_sync_ind(const module_id_t module_id,
 
 void nr_mac_rrc_msg3_ind(const module_id_t mod_id, int rnti, int gnb_id) {}
 
-void nr_mac_rrc_ra_ind(const module_id_t mod_id, int frame, bool success) {}
+void nr_mac_rrc_ra_ind(const module_id_t mod_id, bool success) {}
 
 void nr_mac_rrc_inactivity_timer_ind(const module_id_t mod_id) {}
 

openair2/COMMON/mac_messages_types.h

@@ -72,7 +72,6 @@
 // Messages between RRC and MAC layers
 
 typedef struct NRRrcMacRaInd_s {
-  uint32_t frame;
   bool RA_succeeded;
 } NRRrcMacRaInd;
 

openair2/LAYER2/NR_MAC_UE/mac_proto.h

@@ -292,15 +292,8 @@ void configure_csi_resource_mapping(fapi_nr_dl_config_csirs_pdu_rel15_t *csirs_c
                                     uint32_t bwp_size,
                                     uint32_t bwp_start);
 
-/* \brief This function schedules the Msg3 transmission
-@param
-@param
-@param
-@returns void
-*/
-void nr_ue_msg3_scheduler(NR_UE_MAC_INST_t *mac, frame_t current_frame, slot_t current_slot, uint8_t Msg3_tda_id);
 
-void nr_ra_contention_resolution_failed(RA_config_t *ra);
+void nr_ra_contention_resolution_failed(NR_UE_MAC_INST_t *mac);
 void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame_t frame, const int slot);
 void nr_ra_backoff_setting(RA_config_t *ra);
 void nr_get_RA_window(NR_UE_MAC_INST_t *mac);

openair2/LAYER2/NR_MAC_UE/main_ue_nr.c

@@ -180,9 +180,11 @@ void reset_mac_inst(NR_UE_MAC_INST_t *nr_mac)
   if (nr_mac->data_inactivity_timer)
     nr_timer_stop(nr_mac->data_inactivity_timer);
   nr_timer_stop(&nr_mac->time_alignment_timer);
-  nr_timer_stop(&nr_mac->ra.contention_resolution_timer);
   nr_timer_stop(&nr_mac->scheduling_info.sr_DelayTimer);
   nr_timer_stop(&nr_mac->scheduling_info.retxBSR_Timer);
+  nr_timer_stop(&nr_mac->ra.response_window_timer);
+  nr_timer_stop(&nr_mac->ra.RA_backoff_timer);
+  nr_timer_stop(&nr_mac->ra.contention_resolution_timer);
   for (int i = 0; i < NR_MAX_SR_ID; i++)
     nr_timer_stop(&nr_mac->scheduling_info.sr_info[i].prohibitTimer);
 
@@ -194,8 +196,10 @@ void reset_mac_inst(NR_UE_MAC_INST_t *nr_mac)
     nr_mac->ul_harq_info[k].last_ndi = -1; // initialize to invalid value
 
   // stop any ongoing RACH procedure
-  if (nr_mac->ra.ra_state < nrRA_SUCCEEDED)
+  if (nr_mac->ra.RA_active) {
     nr_mac->ra.ra_state = nrRA_UE_IDLE;
+    nr_mac->ra.RA_active = false;
+  }
 
   // discard explicitly signalled contention-free Random Access Resources
   // TODO not sure what needs to be done here

openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c

@@ -879,6 +879,7 @@ bool init_RA(NR_UE_MAC_INST_t *mac, int frame)
   // Random acces procedure initialization
   mac->state = UE_PERFORMING_RA;
   ra->RA_active = true;
+  ra->msg3_C_RNTI = false;
   NR_PRACH_RESOURCES_t *prach_resources = &ra->prach_resources;
   fapi_nr_config_request_t *cfg = &mac->phy_config.config_req;
   // flush MSG3 buffer
@@ -1234,7 +1235,7 @@ void nr_ra_succeeded(NR_UE_MAC_INST_t *mac, const uint8_t gNB_index, const frame
   ra->ra_state = nrRA_SUCCEEDED;
   mac->state = UE_CONNECTED;
   free_and_zero(ra->Msg3_buffer);
-  nr_mac_rrc_ra_ind(mac->ue_id, frame, true);
+  nr_mac_rrc_ra_ind(mac->ue_id, true);
 }
 
 void nr_ra_backoff_setting(RA_config_t *ra)
@@ -1247,8 +1248,10 @@ void nr_ra_backoff_setting(RA_config_t *ra)
   nr_timer_start(&ra->RA_backoff_timer);
 }
 
-void nr_ra_contention_resolution_failed(RA_config_t *ra)
+void nr_ra_contention_resolution_failed(NR_UE_MAC_INST_t *mac)
 {
+  LOG_W(MAC, "[UE %d] Contention resolution failed\n", mac->ue_id);
+  RA_config_t *ra = &mac->ra;
   // discard the TEMPORARY_C-RNTI
   ra->t_crnti = 0;
   // flush MSG3 buffer
@@ -1256,7 +1259,8 @@ void nr_ra_contention_resolution_failed(RA_config_t *ra)
   NR_PRACH_RESOURCES_t *prach_resources = &ra->prach_resources;
   prach_resources->preamble_tx_counter++;
   if (prach_resources->preamble_tx_counter == ra->preambleTransMax + 1) {
-    // TODO indicate a Random Access problem to upper layers
+    // indicate a Random Access problem to upper layers
+    nr_mac_rrc_ra_ind(mac->ue_id, false);
   } else {
     // TODO handle msgA-TransMax (go back to 4-step if the threshold is reached)
     // starting backoff time
@@ -1275,7 +1279,8 @@ void nr_rar_not_successful(NR_UE_MAC_INST_t *mac)
     // if the Random Access Preamble is transmitted on the SpCell
     // TODO to be verified, this means SA if I'm not mistaken
     if (IS_SA_MODE(get_softmodem_params())) {
-      // TODO indicate a Random Access problem to upper layers
+      // indicate a Random Access problem to upper layers
+      nr_mac_rrc_ra_ind(mac->ue_id, false);
     } else {
       // if the Random Access Preamble is transmitted on an SCell:
       // consider the Random Access procedure unsuccessfully completed.

openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

@@ -3722,7 +3722,7 @@ void nr_ue_process_mac_pdu(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *dl_i
             nr_ra_succeeded(mac, gNB_index, frameP, slot);
           } else if (!ra_success) {
             // consider this Contention Resolution not successful and discard the successfully decoded MAC PDU
-            nr_ra_contention_resolution_failed(ra);
+            nr_ra_contention_resolution_failed(mac);
             return;
           }
         }

openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c

@@ -194,7 +194,7 @@ void update_mac_timers(NR_UE_MAC_INST_t *mac)
     handle_time_alignment_timer_expired(mac);
   bool contention_resolution_expired = nr_timer_tick(&mac->ra.contention_resolution_timer);
   if (contention_resolution_expired)
-    nr_ra_contention_resolution_failed(&mac->ra);
+    nr_ra_contention_resolution_failed(mac);
   for (int j = 0; j < NR_MAX_SR_ID; j++)
     nr_timer_tick(&mac->scheduling_info.sr_info[j].prohibitTimer);
   nr_timer_tick(&mac->scheduling_info.sr_DelayTimer);

openair2/LAYER2/NR_MAC_UE/tests/test_nr_ue_ra_procedures.cpp

@@ -29,7 +29,7 @@ softmodem_params_t *get_softmodem_params(void)
 {
   return &softmodem_params;
 }
-void nr_mac_rrc_ra_ind(const module_id_t mod_id, int frame, bool success)
+void nr_mac_rrc_ra_ind(const module_id_t mod_id, bool success)
 {
 }
 tbs_size_t mac_rlc_data_req(const module_id_t module_idP,

openair2/RRC/NR_UE/L2_interface_ue.c

@@ -177,10 +177,9 @@ void nr_ue_rrc_timer_trigger(int instance, int frame, int gnb_id)
   itti_send_msg_to_task(TASK_RRC_NRUE, instance, message_p);
 }
 
-void nr_mac_rrc_ra_ind(const module_id_t mod_id, int frame, bool success)
+void nr_mac_rrc_ra_ind(const module_id_t mod_id, bool success)
 {
   MessageDef *message_p = itti_alloc_new_message(TASK_MAC_UE, 0, NR_RRC_MAC_RA_IND);
-  NR_RRC_MAC_RA_IND (message_p).frame = frame;
   NR_RRC_MAC_RA_IND (message_p).RA_succeeded = success;
   itti_send_msg_to_task(TASK_RRC_NRUE, GNB_MODULE_ID_TO_INSTANCE(mod_id), message_p);
 }

openair2/RRC/NR_UE/L2_interface_ue.h

@@ -39,7 +39,7 @@ void nr_mac_rrc_data_ind_ue(const module_id_t module_id,
 void nr_mac_rrc_inactivity_timer_ind(const module_id_t mod_id);
 void nr_mac_rrc_msg3_ind(const module_id_t mod_id, const int rnti, int gnb_id);
 void nr_ue_rrc_timer_trigger(int instance, int frame, int gnb_id);
-void nr_mac_rrc_ra_ind(const module_id_t mod_id, int frame, bool success);
+void nr_mac_rrc_ra_ind(const module_id_t mod_id, bool success);
 void nsa_sendmsg_to_lte_ue(const void *message, size_t msg_len, Rrc_Msg_Type_t msg_type);
 void process_msg_rcc_to_mac(MessageDef *msg);
 #endif

openair2/RRC/NR_UE/rrc_UE.c

@@ -1975,6 +1975,16 @@ void nr_rrc_handle_ra_indication(NR_UE_RRC_INST_t *rrc, bool ra_succeeded)
     nr_timer_stop(&timers->T304);
     // TODO handle the rest of procedures as described in 5.3.5.3 for when
     // reconfigurationWithSync is included in spCellConfig
+  } else if (!ra_succeeded) {
+    // upon random access problem indication from MCG MAC
+    // while neither T300, T301, T304, T311 nor T319 are running
+    // consider radio link failure to be detected
+    if (!nr_timer_is_active(&timers->T300)
+        && !nr_timer_is_active(&timers->T301)
+        && !nr_timer_is_active(&timers->T304)
+        && !nr_timer_is_active(&timers->T311)
+        && !nr_timer_is_active(&timers->T319))
+      handle_rlf_detection(rrc);
   }
 }
 
@@ -2040,11 +2050,10 @@ void *rrc_nrue(void *notUsed)
 
   case NR_RRC_MAC_RA_IND:
     LOG_D(NR_RRC,
-	  "[UE %ld] Received %s: frame %d RA %s\n",
-	  rrc->ue_id,
-	  ITTI_MSG_NAME(msg_p),
-	  NR_RRC_MAC_RA_IND(msg_p).frame,
-	  NR_RRC_MAC_RA_IND(msg_p).RA_succeeded ? "successful" : "failed");
+          "[UE %ld] Received %s: RA %s\n",
+          rrc->ue_id,
+          ITTI_MSG_NAME(msg_p),
+          NR_RRC_MAC_RA_IND(msg_p).RA_succeeded ? "successful" : "failed");
     nr_rrc_handle_ra_indication(rrc, NR_RRC_MAC_RA_IND(msg_p).RA_succeeded);
     break;