trigger RA DL or UL data arrival during RRC_CONNECTED when UL synchronisation status is non-synchronised

openair2/LAYER2/NR_MAC_UE/config_ue.c

@@ -1578,7 +1578,10 @@ static void configure_timeAlignmentTimer(NR_timer_t *time_alignment_timer, NR_Ti
   }
   // length of slot is (1/2^scs)ms
   uint32_t n_slots = timer_ms != UINT_MAX ? (timer_ms << scs) : UINT_MAX;
+  bool timer_was_active = nr_timer_is_active(time_alignment_timer);
   nr_timer_setup(time_alignment_timer, n_slots, 1); // 1 slot update rate
+  if (timer_was_active)
+    nr_timer_start(time_alignment_timer);
 }
 
 void nr_rrc_mac_config_req_reset(module_id_t module_id,

openair2/LAYER2/NR_MAC_UE/mac_proto.h

@@ -349,6 +349,7 @@ void free_rach_structures(NR_UE_MAC_INST_t *nr_mac, int bwp_id);
 void schedule_RA_after_SR_failure(NR_UE_MAC_INST_t *mac);
 void nr_Msg1_transmitted(NR_UE_MAC_INST_t *mac);
 void nr_Msg3_transmitted(NR_UE_MAC_INST_t *mac, uint8_t CC_id, frame_t frameP, slot_t slotP, uint8_t gNB_id);
+void trigger_MAC_UE_RA(NR_UE_MAC_INST_t *mac);
 void nr_get_msg3_payload(NR_UE_MAC_INST_t *mac, uint8_t *buf, int TBS_max);
 void handle_time_alignment_timer_expired(NR_UE_MAC_INST_t *mac);
 int8_t nr_ue_process_dci_freq_dom_resource_assignment(nfapi_nr_ue_pusch_pdu_t *pusch_config_pdu,

openair2/LAYER2/NR_MAC_UE/nr_ra_procedures.c

@@ -936,23 +936,12 @@ void nr_ra_failed(NR_UE_MAC_INST_t *mac, uint8_t CC_id, NR_PRACH_RESOURCES_t *pr
   }
 }
 
-void schedule_RA_after_SR_failure(NR_UE_MAC_INST_t *mac)
+void trigger_MAC_UE_RA(NR_UE_MAC_INST_t *mac)
 {
   LOG_W(NR_MAC, "Triggering new RA procedure for UE with RNTI %x\n", mac->crnti);
   mac->state = UE_SYNC;
   reset_ra(mac, false);
   mac->ra.msg3_C_RNTI = true;
-  // release PUCCH for all Serving Cells;
-  // release SRS for all Serving Cells;
-  release_PUCCH_SRS(mac);
-  // clear any configured downlink assignments and uplink grants;
-  int scs = mac->current_UL_BWP->scs;
-  if (mac->dl_config_request)
-    memset(mac->dl_config_request, 0, sizeof(*mac->dl_config_request));
-  if (mac->ul_config_request)
-    clear_ul_config_request(mac, scs);
-  // clear any PUSCH resources for semi-persistent CSI reporting
-  // TODO we don't have semi-persistent CSI reporting
 }
 
 void prepare_msg4_feedback(NR_UE_MAC_INST_t *mac, int pid, int ack_nack)

openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

@@ -2967,6 +2967,11 @@ void nr_ue_send_sdu(NR_UE_MAC_INST_t *mac, nr_downlink_indication_t *dl_info, in
       // DCCH logical channel, or CCCH logical channel
       if (mac->data_inactivity_timer)
         nr_timer_start(mac->data_inactivity_timer);
+      // DL data arrival during RRC_CONNECTED when UL synchronisation status is "non-synchronised"
+      if (!nr_timer_is_active(&mac->time_alignment_timer) && mac->state == UE_CONNECTED && !get_softmodem_params()->phy_test) {
+        trigger_MAC_UE_RA(mac);
+        break;
+      }
       nr_ue_process_mac_pdu(mac, dl_info, pdu_id);
       break;
     case FAPI_NR_RX_PDU_TYPE_RAR :

openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c

@@ -1298,6 +1298,24 @@ static bool check_pucchres_for_pending_SR(NR_PUCCH_Config_t *pucch_Config, int t
   return false;
 }
 
+void schedule_RA_after_SR_failure(NR_UE_MAC_INST_t *mac)
+{
+  if (get_softmodem_params()->phy_test)
+    return; // cannot trigger RA in phytest mode
+  trigger_MAC_UE_RA(mac);
+  // release PUCCH for all Serving Cells;
+  // release SRS for all Serving Cells;
+  release_PUCCH_SRS(mac);
+  // clear any configured downlink assignments and uplink grants;
+  int scs = mac->current_UL_BWP->scs;
+  if (mac->dl_config_request)
+    memset(mac->dl_config_request, 0, sizeof(*mac->dl_config_request));
+  if (mac->ul_config_request)
+    clear_ul_config_request(mac, scs);
+  // clear any PUSCH resources for semi-persistent CSI reporting
+  // TODO we don't have semi-persistent CSI reporting
+}
+
 static void nr_update_sr(NR_UE_MAC_INST_t *mac)
 {
   NR_UE_SCHEDULING_INFO *sched_info = &mac->scheduling_info;
@@ -1486,6 +1504,11 @@ void nr_ue_ul_scheduler(NR_UE_MAC_INST_t *mac, nr_uplink_indication_t *ul_info)
       } else {
         if (ulcfg_pdu->pusch_config_pdu.pusch_data.new_data_indicator
             && (mac->state == UE_CONNECTED || (ra->ra_state == nrRA_WAIT_RAR && ra->cfra))) {
+          if (!nr_timer_is_active(&mac->time_alignment_timer) && mac->state == UE_CONNECTED && !get_softmodem_params()->phy_test) {
+            // UL data arrival during RRC_CONNECTED when UL synchronisation status is "non-synchronised"
+            trigger_MAC_UE_RA(mac);
+            return;
+          }
           // Getting IP traffic to be transmitted
           int tx_power = ulcfg_pdu->pusch_config_pdu.tx_power;
           int P_CMAX = nr_get_Pcmax(mac->p_Max,