Keep track of used PUCCH resources

openair2/LAYER2/NR_MAC_gNB/config.c

@@ -350,6 +350,14 @@ int rrc_mac_config_req_gNB(module_id_t Mod_idP,
     AssertFatal(RC.nrmac[Mod_idP]->common_channels[0].vrb_map_UL,
                 "could not allocate memory for RC.nrmac[]->common_channels[0].vrb_map_UL\n");
 
+    for (int i = 0; i < MAX_NUM_BWP; ++i) {
+      RC.nrmac[Mod_idP]->pucch_index_used[i] =
+        calloc(n, sizeof(*RC.nrmac[Mod_idP]->pucch_index_used));
+      AssertFatal(RC.nrmac[Mod_idP]->pucch_index_used[i],
+                  "could not allocate memory for RC.nrmac[]->pucch_index_used[%d]\n",
+                  i);
+    }
+
     LOG_I(MAC,"Configuring common parameters from NR ServingCellConfig\n");
 
     config_common(Mod_idP,

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c

@@ -456,12 +456,15 @@ bool nr_acknack_scheduling(int mod_id,
   curr_pucch->frame = frame;
   curr_pucch->dai_c++;
 
+  int *pucch_index_used = RC.nrmac[mod_id]->pucch_index_used[sched_ctrl->active_ubwp->bwp_Id];
   if (curr_pucch->dai_c == 1) {
     /* FIXME for first allocation: find free resource, here assume first PUCCH
      * resource and first_ul_slot_tdd */
     const int pucch_res = 0;
     curr_pucch->resource_indicator = pucch_res;
     curr_pucch->ul_slot = first_ul_slot_tdd;
+    DevAssert(pucch_index_used[first_ul_slot_tdd] == 0);
+    pucch_index_used[first_ul_slot_tdd] += 1;
 
     /* verify that at that slot and symbol, resources are free.
      * Note: this does not handle potential mux of PUCCH in the same symbol! */

openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h

@@ -551,6 +551,10 @@ typedef struct gNB_MAC_INST_s {
   time_stats_t schedule_pch;
   /// CCE lists
   int cce_list[MAX_NUM_BWP][MAX_NUM_CORESET][MAX_NUM_CCE];
+  /// PUCCH: keep track of the resources has already been used by saving the
+  /// highest index not yet been used in a given slot. Dynamically allocated
+  /// so we can have it for every slot as a function of the numerology
+  int *pucch_index_used[MAX_NUM_BWP];
 
   /// DL preprocessor for differentiated scheduling
   nr_pp_impl_dl pre_processor_dl;

openair2/NR_PHY_INTERFACE/NR_IF_Module.c

@@ -104,6 +104,9 @@ void handle_nr_uci(NR_UL_IND_t *UL_info)
   }
 
   UL_info->uci_ind.num_ucis = 0;
+  // mark corresponding PUCCH resources as free
+  // NOTE: we just assume it is BWP ID 1, to be revised for multiple BWPs
+  RC.nrmac[mod_id]->pucch_index_used[1][slot] = 0;
 }