Merge remote-tracking branch 'origin/NR_MSG3_TPC' into integration_2025_w02 (!3130)

NR gNB MSG3 TPC

This MR improves the handling of MSG3 TPC commands at MAC gNB.

TODO: Compute TPC when PRACH sends a valid power measurements (currently
not the case for OAI L1, to be verified with Aerial L1)

Closes #866

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_RA.c

@@ -675,14 +675,25 @@ static NR_RA_t *find_free_nr_RA(NR_RA_t *ra_base, int ra_count, uint16_t preambl
   return NULL;
 }
 
+static uint8_t nr_get_msg3_tpc(uint32_t preamble_power)
+{
+  // TODO not sure how to implement TPC for MSG3 to be sent in RAR
+  //      maybe using preambleReceivedTargetPower as a term of comparison
+  //      in any case OAI L1 sets this as invalid
+  //      and Aerial report doesn't seem to be reliable (not matching preambleReceivedTargetPower)
+  //      so for now we feedback 0dB TPC
+  return 3; // it means 0dB
+}
+
 void nr_initiate_ra_proc(module_id_t module_idP,
                          int CC_id,
                          frame_t frameP,
-                         sub_frame_t slotP,
+                         int slotP,
                          uint16_t preamble_index,
                          uint8_t freq_index,
                          uint8_t symbol,
-                         int16_t timing_offset)
+                         int16_t timing_offset,
+                         uint32_t preamble_power)
 {
   VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_INITIATE_RA_PROC, 1);
 
@@ -713,6 +724,7 @@ void nr_initiate_ra_proc(module_id_t module_idP,
   ra->preamble_slot = slotP;
   ra->preamble_index = preamble_index;
   ra->timing_offset = timing_offset;
+  ra->msg3_TPC = nr_get_msg3_tpc(preamble_power);
   uint8_t ul_carrier_id = 0; // 0 for NUL 1 for SUL
   ra->RA_rnti = nr_get_ra_rnti(symbol, slotP, freq_index, ul_carrier_id);
 
@@ -2335,9 +2347,7 @@ static void nr_fill_rar(uint8_t Mod_idP, NR_RA_t *ra, uint8_t *dlsch_buffer, nfa
   NR_RA_HEADER_BI *rarbi = (NR_RA_HEADER_BI *) dlsch_buffer;
   NR_RA_HEADER_RAPID *rarh = (NR_RA_HEADER_RAPID *) (dlsch_buffer + 1);
   NR_MAC_RAR *rar = (NR_MAC_RAR *) (dlsch_buffer + 2);
-  unsigned char csi_req = 0, tpc_command;
+  unsigned char csi_req = 0;
-
-  tpc_command = 3; // This is 0 dB in RAR UL grant
 
   /// E/T/R/R/BI subheader ///
   // E = 1, MAC PDU includes another MAC sub-PDU (RAPID)
@@ -2369,8 +2379,6 @@ static void nr_fill_rar(uint8_t Mod_idP, NR_RA_t *ra, uint8_t *dlsch_buffer, nfa
 
   // UL grant
 
-  ra->msg3_TPC = 1; // This is 0 dB in UL DCI
-
   if (pusch_pdu->frequency_hopping)
     AssertFatal(1==0,"PUSCH with frequency hopping currently not supported");
 
@@ -2379,7 +2387,7 @@ static void nr_fill_rar(uint8_t Mod_idP, NR_RA_t *ra, uint8_t *dlsch_buffer, nfa
   int valid_bits = 14;
   int f_alloc = prb_alloc & ((1 << valid_bits) - 1);
 
-  uint32_t ul_grant = csi_req | (tpc_command << 1) | (pusch_pdu->mcs_index << 4) | (ra->Msg3_tda_id << 8) | (f_alloc << 12) | (pusch_pdu->frequency_hopping << 26);
+  uint32_t ul_grant = csi_req | (ra->msg3_TPC << 1) | (pusch_pdu->mcs_index << 4) | (ra->Msg3_tda_id << 8) | (f_alloc << 12) | (pusch_pdu->frequency_hopping << 26);
 
   rar->UL_GRANT_1 = (uint8_t) (ul_grant >> 24) & 0x07;
   rar->UL_GRANT_2 = (uint8_t) (ul_grant >> 16) & 0xff;
@@ -2409,9 +2417,12 @@ static void nr_fill_rar(uint8_t Mod_idP, NR_RA_t *ra, uint8_t *dlsch_buffer, nfa
         rar->TA2 + (rar->TA1 << 5),
         rar->UL_GRANT_4 >> 4,
         rar->UL_GRANT_1 >> 2,
-        tpc_command,
+        ra->msg3_TPC,
         csi_req,
         rar->TCRNTI_2 + (rar->TCRNTI_1 << 8));
+
+  // resetting msg3 TPC to 0dB for possible retransmissions
+  ra->msg3_TPC = 1;
 }
 
 void nr_schedule_RA(module_id_t module_idP,

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c

@@ -987,9 +987,12 @@ static void _nr_rx_sdu(const module_id_t gnb_mod_idP,
       if (ra->ra_state != nrRA_WAIT_Msg3)
         continue;
 
-      if( (frameP!=ra->Msg3_frame) || (slotP!=ra->Msg3_slot))
+      if((frameP!=ra->Msg3_frame) || (slotP!=ra->Msg3_slot))
         continue;
 
+      if (ul_cqi != 0xff)
+        ra->msg3_TPC = nr_get_tpc(target_snrx10, ul_cqi, 30, 0);
+
       handle_msg3_failed_rx(ra, i, gNB_mac->ul_bler.harq_round_max);
     }
   }

openair2/LAYER2/NR_MAC_gNB/mac_proto.h

@@ -120,16 +120,15 @@ void nr_schedule_RA(module_id_t module_idP,
                     nfapi_nr_dl_tti_request_t *DL_req,
                     nfapi_nr_tx_data_request_t *TX_req);
 
-/* \brief Function to indicate a received preamble on PRACH.  It initiates the RA procedure.
+void nr_initiate_ra_proc(module_id_t module_idP,
-@param module_idP Instance ID of gNB
+                         int CC_id,
-@param preamble_index index of the received RA request
+                         frame_t frameP,
-@param slotP Slot number on which to act
+                         int slotP,
-@param timing_offset Offset in samples of the received PRACH w.r.t. eNB timing. This is used to
+                         uint16_t preamble_index,
-@param rnti RA rnti corresponding to this PRACH preamble
+                         uint8_t freq_index,
-@param rach_resource type (0=non BL/CE,1 CE level 0,2 CE level 1, 3 CE level 2,4 CE level 3)
+                         uint8_t symbol,
-*/
+                         int16_t timing_offset,
-void nr_initiate_ra_proc(module_id_t module_idP, int CC_id, frame_t frameP, sub_frame_t slotP,
+                         uint32_t preamble_power);
-                         uint16_t preamble_index, uint8_t freq_index, uint8_t symbol, int16_t timing_offset);
 
 void nr_clear_ra_proc(NR_RA_t *ra);
 

openair2/NR_PHY_INTERFACE/NR_IF_Module.c

@@ -94,7 +94,8 @@ void handle_nr_rach(NR_UL_IND_t *UL_info)
                           UL_info->rach_ind.pdu_list[i].preamble_list[0].preamble_index,
                           UL_info->rach_ind.pdu_list[i].freq_index,
                           UL_info->rach_ind.pdu_list[i].symbol_index,
-                          UL_info->rach_ind.pdu_list[i].preamble_list[0].timing_advance);
+                          UL_info->rach_ind.pdu_list[i].preamble_list[0].timing_advance,
+                          UL_info->rach_ind.pdu_list[i].preamble_list[0].preamble_pwr);
     }
   }
 }