gNB: fix NTN real-time issue for large k2 values (e.g. GEO satellite)

move allocation of UL_tti_req_ahead array from scheduling to start-up phase

openair2/LAYER2/NR_MAC_gNB/config.c

@@ -475,13 +475,17 @@ void nr_mac_config_scc(gNB_MAC_INST *nrmac,
               scc->ssb_PositionsInBurst->present);
 
   const int n = nr_slots_per_frame[*scc->ssbSubcarrierSpacing];
-  nrmac->vrb_map_UL_size = n << (int)ceil(log2((NTN_gNB_k2+13)/n+1)); // 13 is upper limit for max_fb_time
-
-  nrmac->common_channels[0].vrb_map_UL = calloc(nrmac->vrb_map_UL_size * MAX_BWP_SIZE, sizeof(uint16_t));
+  int size = n << (int)ceil(log2((NTN_gNB_k2+13)/n+1)); // 13 is upper limit for max_fb_time
 
+  nrmac->vrb_map_UL_size = size;
+  nrmac->common_channels[0].vrb_map_UL = calloc(size * MAX_BWP_SIZE, sizeof(uint16_t));
   AssertFatal(nrmac->common_channels[0].vrb_map_UL,
               "could not allocate memory for RC.nrmac[]->common_channels[0].vrb_map_UL\n");
 
+  nrmac->UL_tti_req_ahead_size = size;
+  nrmac->UL_tti_req_ahead[0] = calloc(size, sizeof(nfapi_nr_ul_tti_request_t));
+  AssertFatal(nrmac->UL_tti_req_ahead[0], "could not allocate memory for nrmac->UL_tti_req_ahead[0]\n");
+
   LOG_I(NR_MAC, "Configuring common parameters from NR ServingCellConfig\n");
 
   int num_pdsch_antenna_ports = pdsch_AntennaPorts.N1 * pdsch_AntennaPorts.N2 * pdsch_AntennaPorts.XP;

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c

@@ -2906,22 +2906,16 @@ int ul_buffer_index(int frame, int slot, int scs, int size)
 
 void UL_tti_req_ahead_initialization(gNB_MAC_INST * gNB, NR_ServingCellConfigCommon_t *scc, int n, int CCid, frame_t frameP, int slotP, int scs)
 {
-
-  if(gNB->UL_tti_req_ahead[CCid])
+  if(gNB->UL_tti_req_ahead[CCid][1].Slot == 1)
     return;
 
-  int size = n << (int)ceil(log2((NTN_gNB_k2+13)/n+1)); // 13 is upper limit for max_fb_time
-
-  gNB->UL_tti_req_ahead_size = size;
-  gNB->UL_tti_req_ahead[CCid] = calloc(size, sizeof(nfapi_nr_ul_tti_request_t));
-  AssertFatal(gNB->UL_tti_req_ahead[CCid], "could not allocate memory for gNB->UL_tti_req_ahead[]\n");
   /* fill in slot/frame numbers: slot is fixed, frame will be updated by scheduler
    * consider that scheduler runs sl_ahead: the first sl_ahead slots are
    * already "in the past" and thus we put frame 1 instead of 0! */
   
-  for (int i = 0; i < size; ++i) {
+  for (int i = 0; i < gNB->UL_tti_req_ahead_size; ++i) {
     int abs_slot = frameP * n + slotP + i;
-    nfapi_nr_ul_tti_request_t *req = &gNB->UL_tti_req_ahead[CCid][abs_slot % size];
+    nfapi_nr_ul_tti_request_t *req = &gNB->UL_tti_req_ahead[CCid][abs_slot % gNB->UL_tti_req_ahead_size];
     req->SFN = (abs_slot / n) % MAX_FRAME_NUMBER;
     req->Slot = abs_slot % n;
   }