UL_tti_req_ahead: Create PUSCH PDU directly within nr_fill_nfapi_ul_pdu()

Use a "future" UL_tti_req structure to save in between scheduling and
reception slots. Should also work for FDD.

openair2/LAYER2/NR_MAC_gNB/config.c

@@ -322,6 +322,13 @@ int rrc_mac_config_req_gNB(module_id_t Mod_idP,
   if (scc != NULL ) {
     AssertFatal((scc->ssb_PositionsInBurst->present > 0) && (scc->ssb_PositionsInBurst->present < 4), "SSB Bitmap type %d is not valid\n",scc->ssb_PositionsInBurst->present);
 
+    /* dimension UL_tti_req_ahead for number of slots in frame */
+    const uint8_t slots_per_frame[5] = {10, 20, 40, 80, 160};
+    const int n = slots_per_frame[*scc->ssbSubcarrierSpacing];
+    RC.nrmac[Mod_idP]->UL_tti_req_ahead[0] = calloc(n, sizeof(nfapi_nr_ul_tti_request_t));
+    AssertFatal(RC.nrmac[Mod_idP]->UL_tti_req_ahead[0],
+                "could not allocate memory for RC.nrmac[]->UL_tti_req_ahead[]\n");
+
     LOG_I(MAC,"Configuring common parameters from NR ServingCellConfig\n");
 
     config_common(Mod_idP,

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler.c

@@ -285,26 +285,34 @@ void schedule_nr_SRS(module_id_t module_idP, frame_t frameP, sub_frame_t subfram
 */
 
 
-void nr_schedule_pusch(int Mod_idP,
-                       int UE_id,
-                       int num_slots_per_tdd,
-                       int ul_slots,
-                       frame_t frameP,
-                       sub_frame_t slotP) {
-
-  nfapi_nr_ul_tti_request_t *UL_tti_req = &RC.nrmac[Mod_idP]->UL_tti_req[0];
-  NR_UE_info_t *UE_info = &RC.nrmac[Mod_idP]->UE_info;
-  int k = slotP + ul_slots - num_slots_per_tdd;
-  NR_sched_pusch *pusch = &UE_info->UE_sched_ctrl[UE_id].sched_pusch[k];
-  if ((pusch->active == true) && (frameP == pusch->frame) && (slotP == pusch->slot)) {
-    UL_tti_req->SFN = pusch->frame;
-    UL_tti_req->Slot = pusch->slot;
-    UL_tti_req->pdus_list[UL_tti_req->n_pdus].pdu_type = NFAPI_NR_UL_CONFIG_PUSCH_PDU_TYPE;
-    UL_tti_req->pdus_list[UL_tti_req->n_pdus].pdu_size = sizeof(nfapi_nr_pusch_pdu_t);
-    UL_tti_req->pdus_list[UL_tti_req->n_pdus].pusch_pdu = pusch->pusch_pdu;
-    UL_tti_req->n_pdus+=1;
-    memset((void *) &UE_info->UE_sched_ctrl[UE_id].sched_pusch[k],
-           0, sizeof(NR_sched_pusch));
+void nr_schedule_pusch(int mod_id, frame_t frame, sub_frame_t slot) {
+  nfapi_nr_ul_tti_request_t *ul_tti_req = &RC.nrmac[mod_id]->UL_tti_req[0];
+  nfapi_nr_ul_tti_request_t *future_ul_tti_req =
+      &RC.nrmac[mod_id]->UL_tti_req_ahead[0][slot];
+
+  if (future_ul_tti_req->Slot == slot
+      && future_ul_tti_req->SFN == frame
+      && future_ul_tti_req->n_pdus > 0) {
+    LOG_D(MAC, "%4d.%2d copy %d PDUs from future_ul_tti_req\n", frame, slot, future_ul_tti_req->n_pdus);
+    /* the future_UL_tti_req_has data for the current frame/slot pair, copy
+     * everything into the "real" UL_tti_req */
+    ul_tti_req->SFN = future_ul_tti_req->SFN;
+    ul_tti_req->Slot = future_ul_tti_req->Slot;
+    ul_tti_req->n_pdus = future_ul_tti_req->n_pdus;
+    ul_tti_req->rach_present = future_ul_tti_req->rach_present;
+    ul_tti_req->n_ulsch = future_ul_tti_req->n_ulsch;
+    ul_tti_req->n_ulcch = future_ul_tti_req->n_ulcch;
+    ul_tti_req->n_group = future_ul_tti_req->n_group;
+    memcpy(ul_tti_req->pdus_list,
+           future_ul_tti_req->pdus_list,
+           ul_tti_req->n_pdus * sizeof(nfapi_nr_ul_tti_request_number_of_pdus_t));
+    memcpy(ul_tti_req->groups_list,
+           future_ul_tti_req->groups_list,
+           ul_tti_req->n_group * sizeof(nfapi_nr_ul_tti_request_number_of_groups_t));
+    future_ul_tti_req->n_pdus = 0;
+    future_ul_tti_req->n_ulsch = 0;
+    future_ul_tti_req->n_ulcch = 0;
+    future_ul_tti_req->n_group = 0;
   }
 }
 
@@ -433,9 +441,9 @@ void gNB_dlsch_ulsch_scheduler(module_id_t module_idP,
   // inside
   if (UE_info->active[UE_id] && slot < 10) {
     nr_schedule_ulsch(module_idP, frame, slot, num_slots_per_tdd, nr_ulmix_slots, ulsch_in_slot_bitmap);
-    nr_schedule_pusch(module_idP, UE_id, num_slots_per_tdd, nr_ulmix_slots, frame, slot);
   }
 
+  nr_schedule_pusch(module_idP, frame, slot);
 
   if (UE_info->active[UE_id]
       && (is_xlsch_in_slot(dlsch_in_slot_bitmap, slot % num_slots_per_tdd))

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c

@@ -499,9 +499,10 @@ void nr_schedule_ulsch(module_id_t module_id,
    * period, slot 8 (for K2=2, this is at slot 6 in the gNB; because of UE
    * limitations).  Note that if K2 or the TDD configuration is changed, below
    * conditions might exclude each other and never be true */
-  const int slot_idx = (slot + K2) % num_slots_per_tdd;
-  if (is_xlsch_in_slot(ulsch_in_slot_bitmap, slot_idx)
-        && (!get_softmodem_params()->phy_test || slot_idx == 8)) {
+  const int sched_frame = frame + (slot + K2 >= num_slots_per_tdd);
+  const int sched_slot = (slot + K2) % num_slots_per_tdd;
+  if (is_xlsch_in_slot(ulsch_in_slot_bitmap, sched_slot)
+        && (!get_softmodem_params()->phy_test || sched_slot == 8)) {
 
     const int target_ss = NR_SearchSpace__searchSpaceType_PR_ue_Specific;
     NR_SearchSpace_t *ss = get_searchspace(bwp, target_ss);
@@ -536,15 +537,20 @@ void nr_schedule_ulsch(module_id_t module_id,
 
     uint16_t rnti = UE_info->rnti[UE_id];
 
-    int first_ul_slot = num_slots_per_tdd - ul_slots;
-    NR_sched_pusch *pusch_sched = &UE_info->UE_sched_ctrl[UE_id].sched_pusch[slot+K2-first_ul_slot];
-    pusch_sched->frame = frame;
-    pusch_sched->slot = slot + K2;
-    pusch_sched->active = true;
-
-    LOG_D(MAC, "Scheduling UE specific PUSCH\n");
-    //UL_tti_req = &nr_mac->UL_tti_req[CC_id];
-
+    /* PUSCH in a later slot, but corresponding DCI now! */
+    nfapi_nr_ul_tti_request_t *future_ul_tti_req = &RC.nrmac[module_id]->UL_tti_req_ahead[0][sched_slot];
+    future_ul_tti_req->SFN = sched_frame;
+    future_ul_tti_req->Slot = sched_slot;
+    nfapi_nr_ul_dci_request_t *ul_dci_req = &RC.nrmac[module_id]->UL_dci_req[0];
+    ul_dci_req->SFN = frame;
+    ul_dci_req->Slot = slot;
+    future_ul_tti_req->pdus_list[future_ul_tti_req->n_pdus].pdu_type = NFAPI_NR_UL_CONFIG_PUSCH_PDU_TYPE;
+    future_ul_tti_req->pdus_list[future_ul_tti_req->n_pdus].pdu_size = sizeof(nfapi_nr_pusch_pdu_t);
+    nfapi_nr_pusch_pdu_t *pusch_pdu = &future_ul_tti_req->pdus_list[future_ul_tti_req->n_pdus].pusch_pdu;
+    memset(pusch_pdu, 0, sizeof(nfapi_nr_pusch_pdu_t));
+    future_ul_tti_req->n_pdus += 1;
+
+    LOG_D(MAC, "%4d.%2d Scheduling UE specific PUSCH\n", frame, slot);
 
     int dci_formats[2];
     if (ss->searchSpaceType->choice.ue_Specific->dci_Formats)
@@ -554,8 +560,6 @@ void nr_schedule_ulsch(module_id_t module_id,
 
     int rnti_types[2] = { NR_RNTI_C, 0 };
 
-    nfapi_nr_pusch_pdu_t  *pusch_pdu = &pusch_sched->pusch_pdu;
-    memset(pusch_pdu,0,sizeof(nfapi_nr_pusch_pdu_t));
     //Resource Allocation in time domain
     const int startSymbolAndLength = tdaList->list.array[tda]->startSymbolAndLength;
     int StartSymbolIndex, NrOfSymbols;
@@ -709,7 +713,7 @@ void nr_schedule_ulsch(module_id_t module_id,
     pusch_pdu->pusch_data.rv_index = nr_rv_round_map[cur_harq->round];
 
     cur_harq->state = ACTIVE_SCHED;
-    cur_harq->last_tx_slot = pusch_sched->slot;
+    cur_harq->last_tx_slot = sched_slot;
 
     uint8_t num_dmrs_symb = 0;
     for(int i = pusch_pdu->start_symbol_index; i < pusch_pdu->start_symbol_index + pusch_pdu->nr_of_symbols; i++)

openair2/LAYER2/NR_MAC_gNB/mac_proto.h

@@ -178,12 +178,7 @@ void config_uldci(NR_BWP_Uplink_t *ubwp,
                   int time_domain_assignment, uint8_t tpc,
                   int n_ubwp, int bwp_id);
 
-void nr_schedule_pusch(int Mod_idP,
-                       int UE_id,
-                       int num_slots_per_tdd,
-                       int ul_slots,
-                       frame_t       frameP,
-                       sub_frame_t   slotP);
+void nr_schedule_pusch(int Mod_idP, frame_t frameP, sub_frame_t slotP);
 
 void nr_schedule_pucch(int Mod_idP,
                        int UE_id,

openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h

@@ -469,6 +469,9 @@ typedef struct gNB_MAC_INST_s {
   nfapi_nr_dl_tti_request_t         DL_req[NFAPI_CC_MAX];
   /// NFAPI UL TTI Request Structure (this is from the new SCF specs)
   nfapi_nr_ul_tti_request_t         UL_tti_req[NFAPI_CC_MAX];
+  /// NFAPI UL TTI Request Structure for future TTIs, dynamically allocated
+  /// because length depends on number of slots
+  nfapi_nr_ul_tti_request_t        *UL_tti_req_ahead[NFAPI_CC_MAX];
   /// NFAPI HI/DCI0 Config Request Structure
   nfapi_nr_ul_dci_request_t         UL_dci_req[NFAPI_CC_MAX];
   /// NFAPI DL PDU structure