Add logic for measgap scheduling

common/utils/nr/nr_common.c

@@ -1415,6 +1415,11 @@ uint32_t nr_timer_elapsed_time(const NR_timer_t *timer)
   return timer->counter;
 }
 
+uint32_t nr_timer_remaining_time(const NR_timer_t *timer)
+{
+  return timer->target - timer->counter;
+}
+
 void nr_timer_setup(NR_timer_t *timer, const uint32_t target, const uint32_t step)
 {
   timer->target = target;

common/utils/nr/nr_common.h

@@ -222,6 +222,12 @@ bool nr_timer_is_active(const NR_timer_t *timer);
  * @return Time passed since start of timer
  */
 uint32_t nr_timer_elapsed_time(const NR_timer_t *timer);
+/**
+ * @brief To return how much time is left until the timer expires
+ * @param timer Timer to be checked
+ * @return Time left until the timer expires
+ */
+uint32_t nr_timer_remaining_time(const NR_timer_t *timer);
 
 int set_default_nta_offset(frequency_range_t freq_range, uint32_t samples_per_subframe);
 

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler.c

@@ -201,6 +201,7 @@ void gNB_dlsch_ulsch_scheduler(module_id_t module_idP, frame_t frame, slot_t slo
     LOG_I(NR_MAC, "Frame.Slot %d.%d\n%s\n", frame, slot, stats_output);
   }
 
+  nr_measgap_scheduling(gNB, frame, slot);
   nr_mac_update_timers(module_idP, frame, slot);
 
   if (wait_prach_completed || get_softmodem_params()->phy_test) {

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_dlsch.c

@@ -628,6 +628,7 @@ static void pf_dl(module_id_t module_id,
     NR_sched_pdsch_t *sched_pdsch = &sched_ctrl->sched_pdsch;
     /* get the PID of a HARQ process awaiting retrnasmission, or -1 otherwise */
     sched_pdsch->dl_harq_pid = sched_ctrl->retrans_dl_harq.head;
+
     /* Calculate Throughput */
     const float a = 0.01f;
     const uint32_t b = UE->mac_stats.dl.current_bytes;

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c

@@ -3158,6 +3158,37 @@ void nr_csirs_scheduling(int Mod_idP, frame_t frame, slot_t slot, nfapi_nr_dl_tt
   }
 }
 
+void nr_measgap_scheduling(gNB_MAC_INST *nr_mac, frame_t frame, sub_frame_t slot)
+{
+  NR_SCHED_ENSURE_LOCKED(&nr_mac->sched_lock);
+
+  NR_UEs_t *UE_info = &nr_mac->UE_info;
+  UE_iterator(UE_info->connected_ue_list, UE) {
+    measgap_config_t *mgc = &UE->measgap_config;
+    if (!mgc->enable)
+      continue;
+
+    const int slots_frame = nr_mac->frame_structure.numb_slots_frame;
+    const frame_t f = (frame + (slot + mgc->n_slots_advance) / slots_frame) % 1024;
+    const slot_t s = (slot + mgc->n_slots_advance) % slots_frame;
+
+    // TS 38 331 - Section 5.5.2.9 Measurement gap configuration
+    if (!(((f % (mgc->mgrp_ms / 10)) == (mgc->gapOffset / 10)) && (s == mgc->gapOffset % 10)))
+      continue;
+
+    NR_timer_t *t = &UE->UE_sched_ctrl.transm_interrupt;
+    interrupt_followup_action_t a = nr_timer_is_active(t) ? UE->interrupt_action : FOLLOW_INSYNC;
+    // start a timer to stop scheduling UE during MeasGap, or extend timer for
+    // duration of measGap with existing follow-up action
+    // TODO: if the timer is running, it might be to stop scheduling of the UE afterwards, but then it does not make sense to stop
+    //  scheduling the UE now, we should maybe just skip it?
+    if (!nr_timer_is_active(t) || nr_timer_remaining_time(t) < mgc->mgl_slots) {
+      nr_mac_trigger_ul_failure(&UE->UE_sched_ctrl, UE->current_DL_BWP.scs); /* set the UE to "not active" */
+      nr_mac_interrupt_ue_transmission(nr_mac, UE, a, mgc->mgl_slots);
+    }
+  }
+}
+
 void nr_mac_clean_cellgroup(NR_CellGroupConfig_t *cell_group)
 {
   DevAssert(cell_group != NULL);
@@ -3281,9 +3312,12 @@ void nr_mac_update_timers(module_id_t module_id, frame_t frame, slot_t slot)
     if (nr_timer_tick(&sched_ctrl->transm_interrupt)) {
       /* expired */
       nr_timer_stop(&sched_ctrl->transm_interrupt);
-      if (UE->interrupt_action == FOLLOW_OUTOFSYNC)
+      if (UE->interrupt_action == FOLLOW_OUTOFSYNC) {
         nr_mac_trigger_ul_failure(sched_ctrl, UE->current_DL_BWP.scs);
-      /* else: default FOLLOW_INSYNC: nothing to do (UE is now active again) */
+      } else {
+        DevAssert(UE->interrupt_action == FOLLOW_INSYNC);
+        nr_mac_reset_ul_failure(sched_ctrl);
+      }
     }
   }
 }

openair2/LAYER2/NR_MAC_gNB/mac_proto.h

@@ -203,6 +203,8 @@ void nr_csirs_scheduling(int Mod_idP, frame_t frame, slot_t slot, nfapi_nr_dl_tt
 
 void nr_csi_meas_reporting(int Mod_idP, frame_t frameP, slot_t slotP);
 
+void nr_measgap_scheduling(gNB_MAC_INST *nr_mac, frame_t frame, sub_frame_t slot);
+
 int nr_acknack_scheduling(gNB_MAC_INST *mac,
                           NR_UE_info_t *UE,
                           frame_t frameP,