Some more UE timing fixes

- Check for timing_advance update _after_ RX (and TX) processing
- Update writeBlockSize when timing_advance value changes (for USRP)
- ignore timestamp when pre-reading the first OFDM symbol of a frame (for rfsimulator)
- do not busy wait for a finished RX-TX thread, use blocking wait instead

executables/nr-ue.c

@@ -473,21 +473,22 @@ void UE_processing(void *arg) {
   UE_nr_rxtx_proc_t *proc = &rxtxD->proc;
   PHY_VARS_NR_UE    *UE   = rxtxD->UE;
 
-  uint8_t gNB_id = 0;
-
-  // params for UL time alignment procedure
-  NR_UL_TIME_ALIGNMENT_t *ul_time_alignment = &UE->ul_time_alignment[gNB_id];
-  uint8_t numerology = UE->frame_parms.numerology_index;
-  uint16_t bwp_ul_NB_RB = UE->frame_parms.N_RB_UL;
-  int slot_tx = proc->nr_tti_tx;
-  int frame_tx = proc->frame_tx;
+  processSlotRX(UE, proc);
+  processSlotTX(UE, proc);
 
   /* UL time alignment
   // If the current tx frame and slot match the TA configuration in ul_time_alignment
   // then timing advance is processed and set to be applied in the next UL transmission */
   if (UE->mac_enabled == 1) {
+    uint8_t gNB_id = 0;
+    NR_UL_TIME_ALIGNMENT_t *ul_time_alignment = &UE->ul_time_alignment[gNB_id];
+    int slot_tx = proc->nr_tti_tx;
+    int frame_tx = proc->frame_tx;
 
     if (frame_tx == ul_time_alignment->ta_frame && slot_tx == ul_time_alignment->ta_slot) {
+      uint8_t numerology = UE->frame_parms.numerology_index;
+      uint16_t bwp_ul_NB_RB = UE->frame_parms.N_RB_UL;
+
       LOG_D(PHY,"Applying timing advance -- frame %d -- slot %d\n", frame_tx, slot_tx);
 
       //if (nfapi_mode!=3){
@@ -497,9 +498,6 @@ void UE_processing(void *arg) {
       //}
     }
   }
-
-  processSlotRX(UE, proc);
-  processSlotTX(UE, proc);
 }
 
 void dummyWrite(PHY_VARS_NR_UE *UE,openair0_timestamp timestamp, int writeBlockSize) {
@@ -624,6 +622,7 @@ void *UE_thread(void *arg) {
   notifiedFIFO_t freeBlocks;
   initNotifiedFIFO_nothreadSafe(&freeBlocks);
   NR_UE_MAC_INST_t *mac = get_mac_inst(0);
+  int timing_advance = UE->timing_advance;
 
   for (int i=0; i<RX_NB_TH+1; i++)  // RX_NB_TH working + 1 we are making to be pushed
     pushNotifiedFIFO_nothreadSafe(&freeBlocks,
@@ -728,21 +727,26 @@ void *UE_thread(void *arg) {
 
     for (int i=0; i<UE->frame_parms.nb_antennas_tx; i++)
       txp[i] = (void *)&UE->common_vars.txdata[i][UE->frame_parms.get_samples_slot_timestamp(
-               ((curMsg->proc.nr_tti_rx + DURATION_RX_TO_TX - RX_NB_TH)%nb_slot_frame),&UE->frame_parms,0)];
+               ((slot_nr + DURATION_RX_TO_TX - RX_NB_TH)%nb_slot_frame),&UE->frame_parms,0)];
 
     int readBlockSize, writeBlockSize;
 
     if (slot_nr<(nb_slot_frame - 1)) {
       readBlockSize=get_readBlockSize(slot_nr, &UE->frame_parms);
-      writeBlockSize=UE->frame_parms.get_samples_per_slot(curMsg->proc.nr_tti_tx,&UE->frame_parms);
+      writeBlockSize=UE->frame_parms.get_samples_per_slot((slot_nr + DURATION_RX_TO_TX - RX_NB_TH) % nb_slot_frame, &UE->frame_parms);
     } else {
       UE->rx_offset_diff = computeSamplesShift(UE);
       readBlockSize=get_readBlockSize(slot_nr, &UE->frame_parms) -
                     UE->rx_offset_diff;
-      writeBlockSize=UE->frame_parms.get_samples_per_slot(curMsg->proc.nr_tti_tx,&UE->frame_parms) -
+      writeBlockSize=UE->frame_parms.get_samples_per_slot((slot_nr + DURATION_RX_TO_TX - RX_NB_TH) % nb_slot_frame, &UE->frame_parms)-
                      UE->rx_offset_diff;
     }
 
+    if (UE->timing_advance != timing_advance) {
+      writeBlockSize -= UE->timing_advance - timing_advance;
+      timing_advance = UE->timing_advance;
+    }
+
     AssertFatal(readBlockSize ==
                 UE->rfdevice.trx_read_func(&UE->rfdevice,
                                            &timestamp,
@@ -754,14 +758,15 @@ void *UE_thread(void *arg) {
       // read in first symbol of next frame and adjust for timing drift
       int first_symbols=UE->frame_parms.ofdm_symbol_size+UE->frame_parms.nb_prefix_samples0; // first symbol of every frames
 
-      if ( first_symbols > 0 )
+      if ( first_symbols > 0 ) {
+        openair0_timestamp ignore_timestamp;
         AssertFatal(first_symbols ==
                     UE->rfdevice.trx_read_func(&UE->rfdevice,
-                                               &timestamp,
+                                               &ignore_timestamp,
                                                (void **)UE->common_vars.rxdata,
                                                first_symbols,
                                                UE->frame_parms.nb_antennas_rx),"");
-      else
+      } else
         LOG_E(PHY,"can't compensate: diff =%d\n", first_symbols);
     }
 
@@ -772,18 +777,15 @@ void *UE_thread(void *arg) {
     notifiedFIFO_elt_t *res;
 
     while (nbSlotProcessing >= RX_NB_TH) {
-      if ( (res=tryPullTpool(&nf, Tpool)) != NULL ) {
-        nbSlotProcessing--;
-        processingData_t *tmp=(processingData_t *)res->msgData;
-
-        if (tmp->proc.decoded_frame_rx != -1)
-          decoded_frame_rx=(((mac->mib->systemFrameNumber.buf[0] >> mac->mib->systemFrameNumber.bits_unused)<<4) | tmp->proc.decoded_frame_rx);
-          //decoded_frame_rx=tmp->proc.decoded_frame_rx;
+      res=pullTpool(&nf, Tpool);
+      nbSlotProcessing--;
+      processingData_t *tmp=(processingData_t *)res->msgData;
 
-        pushNotifiedFIFO_nothreadSafe(&freeBlocks,res);
-      }
+      if (tmp->proc.decoded_frame_rx != -1)
+        decoded_frame_rx=(((mac->mib->systemFrameNumber.buf[0] >> mac->mib->systemFrameNumber.bits_unused)<<4) | tmp->proc.decoded_frame_rx);
+        //decoded_frame_rx=tmp->proc.decoded_frame_rx;
 
-      usleep(100);
+      pushNotifiedFIFO_nothreadSafe(&freeBlocks,res);
     }
 
     if (  (decoded_frame_rx != curMsg->proc.frame_rx) &&