Issues with adding timing synchronization

[Violet-J]

Hello everyone,I want to add timing synchronization to the system, so I need sib9, but the value of the sched_info_list is always 1 and cannot be changed. I added this in generate_sibs() under srsRAN/srsgnb/src/stack/rrc/rrc_nr.cc

int32_t rrc_nr::generate_sibs()
{
  if (not cfg.is_standalone) {
    return SRSRAN_SUCCESS;
  }

  // SIB1 packing
  const si_sched_info_s::sched_info_list_l_& sched_info = du_cfg->cell(0).sib1.si_sched_info.sched_info_list;

  // SI messages packing

  cell_ctxt->sibs.resize(8);//cell_ctxt->sibs.resize(1);
  sib2_s& sib2                             = cell_ctxt->sibs[0].set_sib2();
  sib2.cell_resel_info_common.q_hyst.value = sib2_s::cell_resel_info_common_s_::q_hyst_opts::db5;

  sib9_s& sib9                             = cell_ctxt->sibs[7].set_sib9();
  struct timeval tv;
  struct timezone tz;
  gettimeofday(&tv,NULL);
  uint64 mileseconds = tv.tv_sec*1000 + tv.tv_usec/1000 + 2208988800000;
  sib9.time_info.time_info_utc = mileseconds/10;
  printf("utc:%lu\n",sib9.time_info.time_info_utc);

  // msg is array of SI messages, each SI message msg[i] may contain multiple SIBs
  // all SIBs in a SI message msg[i] share the same periodicity

 const uint32_t nof_messages = 
   du_cfg->cell(0).sib1.si_sched_info_present ? du_cfg->cell(0).sib1.si_sched_info.sched_info_list.size() : 0;
  cell_ctxt->sib_buffer.reserve(nof_messages + 1);
  asn1::dyn_array<bcch_dl_sch_msg_s> msg(nof_messages + 1);

  // Copy SIB1 to first SI message
  msg[0].msg.set_c1().set_sib_type1() = du_cfg->cell(0).sib1;

  // Copy rest of SIBs
    printf("nof_messages:%u\n",nof_messages);

  for (uint32_t sched_info_elem = 0; sched_info_elem < nof_messages; sched_info_elem++) {
    printf("Copy rest of SIBs");
    uint32_t msg_index = sched_info_elem + 1; // first msg is SIB1, therefore start with second

    msg[msg_index].msg.set_c1().set_sys_info().crit_exts.set_sys_info();
    auto& sib_list = msg[msg_index].msg.c1().sys_info().crit_exts.sys_info().sib_type_and_info;

    for (uint32_t mapping = 0; mapping < sched_info[sched_info_elem].sib_map_info.size(); ++mapping) {
      uint32_t sibidx = sched_info[sched_info_elem].sib_map_info[mapping].type; // SIB2 == 0
      sib_list.push_back(cell_ctxt->sibs[sibidx]);  
    }

  }

  // Pack payload for all messages

  for (uint32_t msg_index = 0; msg_index < nof_messages + 1; msg_index++) {
    srsran::unique_byte_buffer_t sib_pdu = pack_into_pdu(msg[msg_index]);

    if (sib_pdu == nullptr) {
      printf("Failed to pack SIB");
      logger.error("Failed to pack SIB");
      return SRSRAN_ERROR;
    }

    cell_ctxt->sib_buffer.push_back(std::move(sib_pdu));

    // Log SIBs in JSON format
    fmt::memory_buffer strbuf;
    if (msg_index == 0) {
      fmt::format_to(strbuf, "SIB1 payload");
    } else {
      fmt::format_to(strbuf, "SI message={} payload", msg_index + 1);
    }
    log_rrc_message("BCCH", Tx, *cell_ctxt->sib_buffer.back(), msg[msg_index], srsran::to_c_str(strbuf));
  }

  return SRSRAN_SUCCESS;
}

The UE section is as follows Added in srsRAN/srsue/src/stack/rrc_nr/rrc_nr.cc decode_pdu_bcch_dlsch

void rrc_nr::decode_pdu_bcch_dlsch(srsran::unique_byte_buffer_t pdu)
{
  // Stop BCCH search after successful reception of 1 BCCH block

  bcch_dl_sch_msg_s dlsch_msg;
  asn1::cbit_ref    dlsch_bref(pdu->msg, pdu->N_bytes);
  asn1::SRSASN_CODE err = dlsch_msg.unpack(dlsch_bref);

  if (err != asn1::SRSASN_SUCCESS or dlsch_msg.msg.type().value != bcch_dl_sch_msg_type_c::types_opts::c1) {
    logger.error(pdu->msg, pdu->N_bytes, "Could not unpack BCCH DL-SCH message (%d B).", pdu->N_bytes);
    return;
  }

  log_rrc_message("BCCH-DLSCH", Rx, pdu.get(), dlsch_msg, dlsch_msg.msg.c1().type().to_string());

  if (dlsch_msg.msg.c1().type() == bcch_dl_sch_msg_type_c::c1_c_::types::sib_type1) {
   std::cout << "dlsch_msg.msg.c1().type() = " << dlsch_msg.msg.c1().type() << std::endl;

    logger.info("Processing SIB1 (1/1)");
    handle_sib1(dlsch_msg.msg.c1().sib_type1());
  } else  {  
    sys_info_ies_s::sib_type_and_info_l_& sib_list = 
      dlsch_msg.msg.c1().sys_info().crit_exts.sys_info().sib_type_and_info;

    for (uint32_t i = 0; i < sib_list.size(); ++i) {
      logger.info("Processing SIB%d (%d/%d)", sib_list[i].type().to_number(), i, sib_list.size());
      switch (sib_list[i].type().value) {
        case sib_type_info_s::type_e_::sib_type9:
            if (not meas_cells.serving_cell().has_sib9()) {
            meas_cells.serving_cell().set_sib9(sib_list[i].sib9());
          }
          handle_sib9(dlsch_msg.msg.c1().sib_type9());
          si_acquirer.trigger(si_acquire_proc::sib_received_ev{});
          break;
        default:
          logger.warning("SIB%d is not supported", sib_list[i].type().to_number());
      }
    }
  }
}

At present, there is a problem with sib9, and it is not possible to send SIB9 successfully,therefore, I intend to add the content of SIB9 directly to SIB1, and I add the content of SIB9 in the structure of SIB1, and the following problems occur after running I want to ask how to solve these two problems, especially the first question, how to add and implement SIB9 function normally, which step did I miss? And the second question, I will crash if I add sib9 directly to sib1, how to solve this problem if the first normal solution cannot be implemented