adapt NDI FAPI configuration to PUSCH and resetting TBS when new data

openair1/SCHED_NR_UE/fapi_nr_ue_l1.c

@@ -311,6 +311,13 @@ static void configure_dlsch(NR_UE_DLSCH_t *dlsch0,
     if ((dlsch_config_pdu->dmrs_ports>>i)&0x01) Nl += 1;
   }
   dlsch0->Nl = Nl;
+  if (dlsch_config_pdu->ndi) {
+    dlsch0_harq->first_rx = true;
+    dlsch0_harq->DLround = 0;
+  } else {
+    dlsch0_harq->first_rx = false;
+    dlsch0_harq->DLround++;
+  }
   downlink_harq_process(dlsch0_harq, current_harq_pid, dlsch_config_pdu->ndi, dlsch_config_pdu->rv, dlsch0->rnti_type);
   if (dlsch0_harq->status != ACTIVE) {
     // dlsch0_harq->status not ACTIVE due to false retransmission

openair1/SCHED_NR_UE/harq_nr.c

@@ -177,7 +177,6 @@ void downlink_harq_process(NR_DL_UE_HARQ_t *dl_harq, int harq_pid, int dci_ndi,
     dl_harq->status = ACTIVE;
 
     dl_harq->Ndi = dci_ndi;
-    //dl_harq->status = SCH_IDLE;
-   }
+  }
 }
 

openair2/LAYER2/NR_MAC_UE/mac_defs.h

@@ -500,6 +500,7 @@ typedef struct {
   fapi_nr_csirs_measurements_t csirs_measurements;
 
   /// Last NDI of UL HARQ processes
+  int DL_ndi[NR_MAX_HARQ_PROCESSES];
   int UL_ndi[NR_MAX_HARQ_PROCESSES];
   ////	FAPI-like interface message
   fapi_nr_ul_config_request_t *ul_config_request;

openair2/LAYER2/NR_MAC_UE/main_ue_nr.c

@@ -106,8 +106,11 @@ void nr_ue_mac_default_configs(NR_UE_MAC_INST_t *mac)
     mac->scheduling_info.lc_sched_info[i].LCGID = 0; // defaults to 0 irrespective of SRB or DRB
     mac->scheduling_info.lc_sched_info[i].LCID_status = LCID_EMPTY;
     mac->scheduling_info.lc_sched_info[i].LCID_buffer_remain = 0;
-    for (int k = 0; k < NR_MAX_HARQ_PROCESSES; k++)
-      mac->UL_ndi[k] = -1; // initialize to invalid value
+  }
+
+  for (int k = 0; k < NR_MAX_HARQ_PROCESSES; k++) {
+    mac->UL_ndi[k] = -1; // initialize to invalid value
+    mac->DL_ndi[k] = -1; // initialize to invalid value
   }
 }
 

openair2/LAYER2/NR_MAC_UE/nr_ue_procedures.c

@@ -672,13 +672,30 @@ static int nr_ue_process_dci_dl_10(module_id_t module_id,
   /* MCS */
   dlsch_pdu->mcs = dci->mcs;
 
+  NR_UE_HARQ_STATUS_t *current_harq = &mac->dl_harq_info[dci->harq_pid];
+  /* NDI (only if CRC scrambled by C-RNTI or CS-RNTI or new-RNTI or TC-RNTI)*/
+  if (dl_conf_req->pdu_type == FAPI_NR_DL_CONFIG_TYPE_SI_DLSCH ||
+      dl_conf_req->pdu_type == FAPI_NR_DL_CONFIG_TYPE_RA_DLSCH ||
+      dci->ndi != mac->DL_ndi[dci->harq_pid]) {
+    // new data
+    dlsch_pdu->ndi = 1;
+    current_harq->R = 0;
+    current_harq->TBS = 0;
+  }
+  else
+    dlsch_pdu->ndi = 0;
+
+  if (dl_conf_req->pdu_type != FAPI_NR_DL_CONFIG_TYPE_SI_DLSCH &&
+      dl_conf_req->pdu_type != FAPI_NR_DL_CONFIG_TYPE_RA_DLSCH) {
+    mac->DL_ndi[dci->harq_pid] = dci->ndi;
+  }
+
   dlsch_pdu->qamModOrder = nr_get_Qm_dl(dlsch_pdu->mcs, dlsch_pdu->mcs_table);
   if (dlsch_pdu->qamModOrder == 0) {
     LOG_W(MAC, "Invalid code rate or Mod order, likely due to unexpected DL DCI.\n");
     return -1;
   }
 
-  NR_UE_HARQ_STATUS_t *current_harq = &mac->dl_harq_info[dci->harq_pid];
   int R = nr_get_code_rate_dl(dlsch_pdu->mcs, dlsch_pdu->mcs_table);
   if (R > 0) {
     dlsch_pdu->targetCodeRate = R;
@@ -698,6 +715,11 @@ static int nr_ue_process_dci_dl_10(module_id_t module_id,
                                     1);
     // storing for possible retransmissions
     current_harq->R = dlsch_pdu->targetCodeRate;
+    if (dlsch_pdu->ndi == 0 && current_harq->TBS != dlsch_pdu->TBS) {
+      LOG_W(NR_MAC, "NDI indicates re-transmission but computed TBS %d doesn't match with what previously stored %d\n",
+            dlsch_pdu->TBS, current_harq->TBS);
+      dlsch_pdu->ndi = 1; // treated as new data
+    }
     current_harq->TBS = dlsch_pdu->TBS;
   }
   else {
@@ -715,8 +737,6 @@ static int nr_ue_process_dci_dl_10(module_id_t module_id,
   int bw_tbslbrm = current_DL_BWP ? mac->sc_info.dl_bw_tbslbrm : dlsch_pdu->BWPSize;
   dlsch_pdu->tbslbrm = nr_compute_tbslbrm(dlsch_pdu->mcs_table, bw_tbslbrm, 1);
 
-  /* NDI (only if CRC scrambled by C-RNTI or CS-RNTI or new-RNTI or TC-RNTI)*/
-  dlsch_pdu->ndi = dci->ndi;
   /* RV (only if CRC scrambled by C-RNTI or CS-RNTI or new-RNTI or TC-RNTI)*/
   dlsch_pdu->rv = dci->rv;
   /* HARQ_PROCESS_NUMBER (only if CRC scrambled by C-RNTI or CS-RNTI or new-RNTI or TC-RNTI)*/
@@ -955,7 +975,17 @@ static int nr_ue_process_dci_dl_11(module_id_t module_id,
   /* MCS (for transport block 1)*/
   dlsch_pdu->mcs = dci->mcs;
   /* NDI (for transport block 1)*/
-  dlsch_pdu->ndi = dci->ndi;
+  NR_UE_HARQ_STATUS_t *current_harq = &mac->dl_harq_info[dci->harq_pid];
+  if (dci->ndi != mac->DL_ndi[dci->harq_pid]) {
+    // new data
+    dlsch_pdu->ndi = 1;
+    current_harq->R = 0;
+    current_harq->TBS = 0;
+  }
+  else {
+    dlsch_pdu->ndi = 0;
+  }
+  mac->DL_ndi[dci->harq_pid] = dci->ndi;
   /* RV (for transport block 1)*/
   dlsch_pdu->rv = dci->rv;
   /* MCS (for transport block 2)*/
@@ -1118,7 +1148,6 @@ static int nr_ue_process_dci_dl_11(module_id_t module_id,
     nb_rb_oh = 0;
   int nb_re_dmrs = ((dmrs_type == NULL) ? 6 : 4) * dlsch_pdu->n_dmrs_cdm_groups;
 
-  NR_UE_HARQ_STATUS_t *current_harq = &mac->dl_harq_info[dci->harq_pid];
   int R = nr_get_code_rate_dl(dlsch_pdu->mcs, dlsch_pdu->mcs_table);
   if (R > 0) {
     dlsch_pdu->targetCodeRate = R;
@@ -1131,6 +1160,11 @@ static int nr_ue_process_dci_dl_11(module_id_t module_id,
                                     0,
                                     Nl);
     // storing for possible retransmissions
+    if (dlsch_pdu->ndi == 0 && current_harq->TBS != dlsch_pdu->TBS) {
+      LOG_W(NR_MAC, "NDI indicates re-transmission but computed TBS %d doesn't match with what previously stored %d\n",
+            dlsch_pdu->TBS, current_harq->TBS);
+      dlsch_pdu->ndi = 1; // treated as new data
+    }
     current_harq->R = dlsch_pdu->targetCodeRate;
     current_harq->TBS = dlsch_pdu->TBS;
   }

openair2/LAYER2/NR_MAC_UE/nr_ue_scheduler.c

@@ -627,7 +627,12 @@ int nr_config_pusch_pdu(NR_UE_MAC_INST_t *mac,
     }
 
     /* NDI */
-    pusch_config_pdu->pusch_data.new_data_indicator = dci->ndi != mac->UL_ndi[dci->harq_pid] ? 1 : 0;
+    pusch_config_pdu->pusch_data.new_data_indicator = 0;
+    if (dci->ndi != mac->UL_ndi[dci->harq_pid]) {
+      pusch_config_pdu->pusch_data.new_data_indicator = 1;
+      // if new data reset harq structure
+      memset(&mac->ul_harq_info[dci->harq_pid], 0, sizeof(mac->ul_harq_info[dci->harq_pid]));
+    }
     mac->UL_ndi[dci->harq_pid] = dci->ndi;
     /* RV */
     pusch_config_pdu->pusch_data.rv_index = dci->rv;