fix CORESET start PRB according to standard at OAI gNB

openair1/PHY/NR_TRANSPORT/nr_dci.c

@@ -61,9 +61,13 @@ void nr_generate_dci(PHY_VARS_gNB *gNB,
   int reg_list[MAX_DCI_CORESET][NR_MAX_PDCCH_AGG_LEVEL * NR_NB_REG_PER_CCE];
   nr_fill_reg_list(reg_list, pdcch_pdu_rel15);
   // compute rb_offset and n_prb based on frequency allocation
-  int rb_offset;
-  int n_rb;
-  get_coreset_rballoc(pdcch_pdu_rel15->FreqDomainResource,&n_rb,&rb_offset);
+  int n_rb, cset_start;
+  get_coreset_rballoc(pdcch_pdu_rel15->FreqDomainResource, &n_rb, &cset_start);
+  int additional_offset = 0;
+  // first common RB of the first group of 6 PRBs has common RB index equal to 6 * ⌈BWP_start / 6⌉
+  if (pdcch_pdu_rel15->CoreSetType == 1)
+    additional_offset = (pdcch_pdu_rel15->BWPStart + 5) / 6 * 6 - pdcch_pdu_rel15->BWPStart;
+  int rb_offset = cset_start + additional_offset;
   uint16_t cset_start_sc = frame_parms->first_carrier_offset + (pdcch_pdu_rel15->BWPStart + rb_offset) * NR_NB_SC_PER_RB;
   int idx1 = pdcch_pdu_rel15->StartSymbolIndex+pdcch_pdu_rel15->DurationSymbols;
   int idx2 = (((n_rb + rb_offset + pdcch_pdu_rel15->BWPStart) * 3) + 15) & ~15;
@@ -194,7 +198,7 @@ void nr_generate_dci(PHY_VARS_gNB *gNB,
         // dmrs index depends on reference point for k according to 38.211 7.4.1.3.2
         int dmrs_idx;
         if (pdcch_pdu_rel15->CoreSetType == NFAPI_NR_CSET_CONFIG_PDCCH_CONFIG)
-          dmrs_idx = (reg_list[d][reg_count] + pdcch_pdu_rel15->BWPStart) * 3;
+          dmrs_idx = (reg_list[d][reg_count] + pdcch_pdu_rel15->BWPStart + rb_offset) * 3;
         else
           dmrs_idx = (reg_list[d][reg_count] + rb_offset) * 3;
 

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_dlsch.c

@@ -404,7 +404,8 @@ bwp_info_t get_pdsch_bwp_start_size(gNB_MAC_INST *nr_mac, NR_UE_info_t *UE)
     if (sched_ctrl->coreset->controlResourceSetId == 0) {
       bwp_info.bwpStart = nr_mac->cset0_bwp_start;
     } else {
-      bwp_info.bwpStart = dl_bwp->BWPStart + sched_ctrl->sched_pdcch.rb_start;
+      int additional_offset = (dl_bwp->BWPStart + 5) / 6 * 6 - dl_bwp->BWPStart;
+      bwp_info.bwpStart = dl_bwp->BWPStart + sched_ctrl->sched_pdcch.rb_start + additional_offset;
     }
     if (nr_mac->cset0_bwp_size > 0) {
       bwp_info.bwpSize = min(dl_bwp->BWPSize, nr_mac->cset0_bwp_size);

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c

@@ -454,6 +454,7 @@ static NR_SearchSpace_t *get_searchspace(NR_ServingCellConfigCommon_t *scc,
 /// @param rb_start Output parameter for the starting resource block index of the CORESET
 static void get_coreset_rb_params(const NR_ControlResourceSet_t *coreset, uint16_t *n_rb, uint16_t *rb_start)
 {
+  AssertFatal(!coreset->ext1 || !coreset->ext1->rb_Offset_r16, "rb-Offset in coreset configuration not handled\n");
   *n_rb = 0;
   *rb_start = 0;