Rewrite get_first_ul_slot to use pattern configuration stored in frame_structure

* the function is returning the index of the first full UL slot in tdd_slot_bitmap
  or the first UL slot (including mixed) if the "mixed" flag is provided

common/utils/nr/nr_common.c

@@ -684,11 +684,6 @@ int get_slot_idx_in_period(const int slot, const frame_structure_t *fs)
   return slot % fs->numb_slots_period;
 }
 
-int get_first_ul_slot(int nrofDownlinkSlots, int nrofDownlinkSymbols, int nrofUplinkSymbols)
-{
-  return (nrofDownlinkSlots + (nrofDownlinkSymbols != 0 && nrofUplinkSymbols == 0));
-}
-
 int get_dmrs_port(int nl, uint16_t dmrs_ports)
 {
 

common/utils/nr/nr_common.h

@@ -233,7 +233,6 @@ void reverse_bits_u8(uint8_t const* in, size_t sz, uint8_t* out);
 uint64_t from_nrarfcn(int nr_bandP, uint8_t scs_index, uint32_t dl_nrarfcn);
 uint32_t to_nrarfcn(int nr_bandP, uint64_t dl_CarrierFreq, uint8_t scs_index, uint32_t bw);
 
-int get_first_ul_slot(int nrofDownlinkSlots, int nrofDownlinkSymbols, int nrofUplinkSymbols);
 int cce_to_reg_interleaving(const int R, int k, int n_shift, const int C, int L, const int N_regs);
 int get_SLIV(uint8_t S, uint8_t L);
 void get_coreset_rballoc(uint8_t *FreqDomainResource,int *n_rb,int *rb_offset);

openair2/LAYER2/NR_MAC_gNB/config.c

@@ -374,6 +374,28 @@ static void config_tdd_patterns(NR_TDD_UL_DL_ConfigCommon_t *tdd, frame_structur
         nb_slots_p2);
 }
 
+/**
+ * @brief Get the first UL slot index in period
+ * @param fs frame structure
+ * @param mixed indicates whether to include in the count also mixed slot with UL symbols or only full UL slot
+ * @return slot index
+ */
+int get_first_ul_slot(const frame_structure_t *fs, bool mixed)
+{
+  DevAssert(fs);
+
+  if (fs->is_tdd) {
+    for (int i = 0; i < fs->numb_slots_period; i++) {
+      bool is_mixed = fs->period_cfg.tdd_slot_bitmap[i].num_ul_symbols && fs->period_cfg.tdd_slot_bitmap[i].slot_type == TDD_NR_MIXED_SLOT;
+      if ((mixed && is_mixed) || fs->period_cfg.tdd_slot_bitmap[i].slot_type == TDD_NR_UPLINK_SLOT) {
+        return i;
+      }
+    }
+  }
+
+  return 0; // FDD
+}
+
 /**
  * @brief Get number of DL slots per period (full DL slots + mixed slots with DL symbols)
  */
@@ -908,7 +930,7 @@ void nr_mac_config_scc(gNB_MAC_INST *nrmac, NR_ServingCellConfigCommon_t *scc, c
   int nr_ulstart_slot = 0;
   if (tdd) {
     nr_dl_slots = tdd->nrofDownlinkSlots + (tdd->nrofDownlinkSymbols != 0);
-    nr_ulstart_slot = get_first_ul_slot(tdd->nrofDownlinkSlots, tdd->nrofDownlinkSymbols, tdd->nrofUplinkSymbols);
+    nr_ulstart_slot = get_first_ul_slot(&nrmac->frame_structure, true);
     nr_slots_period /= get_nb_periods_per_frame(tdd->dl_UL_TransmissionPeriodicity);
   } else {
     // if TDD configuration is not present and the band is not FDD, it means it is a dynamic TDD configuration

openair2/LAYER2/NR_MAC_gNB/mac_proto.h

@@ -39,6 +39,7 @@ void set_cset_offset(uint16_t);
 void get_K1_K2(int N1, int N2, int *K1, int *K2, int layers);
 int get_NTN_Koffset(const NR_ServingCellConfigCommon_t *scc);
 
+int get_first_ul_slot(const frame_structure_t *fs, bool mixed);
 int get_ul_slots_per_period(const frame_structure_t *fs);
 int get_ul_slots_per_frame(const frame_structure_t *fs);
 int get_dl_slots_per_period(const frame_structure_t *fs);

openair2/RRC/NR/nr_rrc_config.c

@@ -49,6 +49,7 @@
 #include "constr_TYPE.h"
 #include "executables/softmodem-common.h"
 #include "oai_asn1.h"
+#include "openair2/LAYER2/NR_MAC_gNB/mac_proto.h"
 #include "openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h"
 #include "openair3/UTILS/conversions.h"
 #include "uper_decoder.h"
@@ -1187,10 +1188,10 @@ void set_pucch_power_config(NR_PUCCH_Config_t *pucch_Config, int do_csirs) {
 
 static void set_SR_periodandoffset(NR_SchedulingRequestResourceConfig_t *schedulingRequestResourceConfig, const NR_ServingCellConfigCommon_t *scc, int scs)
 {
-  const NR_TDD_UL_DL_Pattern_t *tdd = scc->tdd_UL_DL_ConfigurationCommon ? &scc->tdd_UL_DL_ConfigurationCommon->pattern1 : NULL;
+  const frame_structure_t *fs = &RC.nrmac[0]->frame_structure;
   int sr_slot = 1; // in FDD SR in slot 1
-  if(tdd)
+  if (fs->is_tdd)
-    sr_slot = get_first_ul_slot(tdd->nrofDownlinkSlots, tdd->nrofDownlinkSymbols, tdd->nrofUplinkSymbols);
+    sr_slot = get_first_ul_slot(fs, true);
 
   schedulingRequestResourceConfig->periodicityAndOffset = calloc(1,sizeof(*schedulingRequestResourceConfig->periodicityAndOffset));
 
@@ -1650,12 +1651,13 @@ static void set_csi_meas_periodicity(const NR_ServingCellConfigCommon_t *scc,
                                      int curr_bwp,
                                      bool is_rsrp)
 {
+  const frame_structure_t *fs = &RC.nrmac[0]->frame_structure;
   const NR_TDD_UL_DL_Pattern_t *tdd = scc->tdd_UL_DL_ConfigurationCommon ? &scc->tdd_UL_DL_ConfigurationCommon->pattern1 : NULL;
   const int n_slots_frame = slotsperframe[*scc->ssbSubcarrierSpacing];
   const int n_ul_slots_period = tdd ? (tdd->nrofUplinkSlots + (tdd->nrofUplinkSymbols > 0)) : n_slots_frame;
   const int n_slots_period = tdd ? n_slots_frame / get_nb_periods_per_frame(tdd->dl_UL_TransmissionPeriodicity) : n_slots_frame;
   const int ideal_period = set_ideal_period(n_slots_period, n_ul_slots_period);
-  const int first_ul_slot_period = tdd ? get_first_ul_slot(tdd->nrofDownlinkSlots, tdd->nrofDownlinkSymbols, tdd->nrofUplinkSymbols) : 0;
+  const int first_ul_slot_period = tdd ? get_first_ul_slot(fs, true) : 0;
   const int num_pucch2 = get_nb_pucch2_per_slot(scc, curr_bwp);
   const int idx = (uid * 2 / num_pucch2) + is_rsrp;
   const int offset = first_ul_slot_period + idx % n_ul_slots_period + (idx / n_ul_slots_period) * n_slots_period;