Merge remote-tracking branch 'origin/issue-1021' into integration_2025_w45 (!3743)

NR UE: fix PDCCH LLR indexing for different search space RB sizes

After !3603 (merged), when multiple search spaces have different CORESET
configurations (different number of RBs), the LLR buffer stride must be
calculated based on the maximum RB size across all search spaces, not the
current search space's RB size.

The LLR buffer is allocated with size based on get_pdcch_max_rbs(), but the
demapping function was using coreset_nbr_rb (current search space) for symbol
stride calculation, causing incorrect LLR extraction when search spaces have
different RB configurations.

This MR tries to fix it.

Closes #1021

openair1/PHY/NR_UE_TRANSPORT/dci_nr.c

@@ -81,7 +81,8 @@ static void nr_pdcch_demapping_deinterleaving(uint32_t coreset_nbr_rb,
                                               uint8_t n_shift,
                                               uint8_t number_of_candidates,
                                               uint16_t *CCE,
-                                              uint8_t *L)
+                                              uint8_t *L,
+                                              int llr_stride_per_symbol)
 {
   /*
    * This function will do demapping and deinterleaving from llr containing demodulated symbols
@@ -168,7 +169,7 @@ static void nr_pdcch_demapping_deinterleaving(uint32_t coreset_nbr_rb,
       for (int cce_count = 0; cce_count < L[c_id]; cce_count++) {
         for (int k = 0; k < NR_NB_REG_PER_CCE / reg_bundle_size_L; k++) { // loop over REG bundles
           int f = f_bundle_j_list_ord[c_id][k + NR_NB_REG_PER_CCE * cce_count / reg_bundle_size_L];
-          c16_t *in = llr + (f * B_rb + symbol_idx * coreset_nbr_rb) * RE_PER_RB_OUT_DMRS;
+          c16_t *in = llr + f * B_rb * RE_PER_RB_OUT_DMRS + symbol_idx * llr_stride_per_symbol;
           // loop over the RBs of the bundle
           memcpy(e_rx + RE_PER_RB_OUT_DMRS * rb_count, in, B_rb * RE_PER_RB_OUT_DMRS * sizeof(*e_rx));
           rb_count += B_rb;
@@ -507,6 +508,7 @@ void nr_pdcch_dci_indication(const UE_nr_rxtx_proc_t *proc,
     fapi_nr_dl_config_dci_dl_pdu_rel15_t *rel15 = &phy_pdcch_config->pdcch_config[ss_idx];
     uint8_t unused_start_symb[NR_SYMBOLS_PER_SLOT] = {0};
     const int num_monitoring_occ = get_pdcch_mon_occasions_slot(rel15, unused_start_symb);
+    const int llr_stride = llr_size / rel15->coreset.duration;
 
     int n_rb;
     int rb_offset;
@@ -525,7 +527,8 @@ void nr_pdcch_dci_indication(const UE_nr_rxtx_proc_t *proc,
                                         rel15->coreset.ShiftIndex,
                                         rel15->number_of_candidates,
                                         rel15->CCE,
-                                        rel15->L);
+                                        rel15->L,
+                                        llr_stride);
 
       nr_dci_decoding_procedure(ue, proc, pdcch_e_rx, rel15, &dci_ind);
     }