openairinterface5g/openair2/RRC/LITE/rrc_common.c

/*! \file rrc_common.c
 * \brief rrc common procedures for eNB and UE
 * \author Navid Nikaein and Raymond Knopp
 * \date 2011 - 2014
 * \version 1.0
 * \company Eurecom
 * \email:  navid.nikaein@eurecom.fr and raymond.knopp@eurecom.fr
 */

#include "defs.h"
#include "extern.h"
#include "LAYER2/MAC/extern.h"
#include "COMMON/openair_defs.h"
#include "COMMON/platform_types.h"
#include "RRC/L2_INTERFACE/openair_rrc_L2_interface.h"
#include "LAYER2/RLC/rlc.h"
#include "COMMON/mac_rrc_primitives.h"
#include "UTIL/LOG/log.h"
#include "asn1_msg.h"
#include "pdcp.h"
#include "UTIL/LOG/vcd_signal_dumper.h"
#include "rrc_eNB_UE_context.h"

#ifdef LOCALIZATION
#include <sys/time.h>
#endif

#define DEBUG_RRC 1
extern eNB_MAC_INST *eNB_mac_inst;
extern UE_MAC_INST *UE_mac_inst;

extern mui_t rrc_eNB_mui;

//configure  BCCH & CCCH Logical Channels and associated rrc_buffers, configure associated SRBs
//-----------------------------------------------------------------------------
void
openair_rrc_on(
  const protocol_ctxt_t* const ctxt_pP
)
//-----------------------------------------------------------------------------
{
  unsigned short i;
  int            CC_id;

  if (ctxt_pP->enb_flag == ENB_FLAG_YES) {
    LOG_I(RRC, PROTOCOL_RRC_CTXT_FMT" OPENAIR RRC IN....\n",
          PROTOCOL_RRC_CTXT_ARGS(ctxt_pP));
    for (CC_id = 0; CC_id < MAX_NUM_CCs; CC_id++) {
      rrc_config_buffer (&eNB_rrc_inst[ctxt_pP->module_id].carrier[CC_id].SI, BCCH, 1);
      eNB_rrc_inst[ctxt_pP->module_id].carrier[CC_id].SI.Active = 1;
      rrc_config_buffer (&eNB_rrc_inst[ctxt_pP->module_id].carrier[CC_id].Srb0, CCCH, 1);
      eNB_rrc_inst[ctxt_pP->module_id].carrier[CC_id].Srb0.Active = 1;
    }
  } else {
    LOG_I(RRC, PROTOCOL_RRC_CTXT_FMT" OPENAIR RRC IN....\n",
          PROTOCOL_RRC_CTXT_ARGS(ctxt_pP));

    for (i = 0; i < NB_eNB_INST; i++) {
      LOG_D(RRC, PROTOCOL_RRC_CTXT_FMT" Activating CCCH (eNB %d)\n",
            PROTOCOL_RRC_CTXT_ARGS(ctxt_pP), i);
      UE_rrc_inst[ctxt_pP->module_id].Srb0[i].Srb_id = CCCH;
      memcpy (&UE_rrc_inst[ctxt_pP->module_id].Srb0[i].Lchan_desc[0], &CCCH_LCHAN_DESC, LCHAN_DESC_SIZE);
      memcpy (&UE_rrc_inst[ctxt_pP->module_id].Srb0[i].Lchan_desc[1], &CCCH_LCHAN_DESC, LCHAN_DESC_SIZE);
      rrc_config_buffer (&UE_rrc_inst[ctxt_pP->module_id].Srb0[i], CCCH, 1);
      UE_rrc_inst[ctxt_pP->module_id].Srb0[i].Active = 1;
    }
  }
}

//-----------------------------------------------------------------------------
int
rrc_init_global_param(
  void
)
//-----------------------------------------------------------------------------
{

  //#ifdef USER_MODE
  //  Rrc_xface = (RRC_XFACE*)malloc16(sizeof(RRC_XFACE));
  //#endif //USRE_MODE

  //  Rrc_xface->openair_rrc_top_init = openair_rrc_top_init;
  //  Rrc_xface->openair_rrc_eNB_init = openair_rrc_eNB_init;
  //  Rrc_xface->openair_rrc_UE_init  = openair_rrc_ue_init;
  //  Rrc_xface->mac_rrc_data_ind     = mac_rrc_data_ind;
  //Rrc_xface->mac_rrc_data_req     = mac_rrc_data_req;
  // Rrc_xface->rrc_data_indP        = (void *)rlcrrc_data_ind;
  //  Rrc_xface->rrc_rx_tx            = rrc_rx_tx;
  //  Rrc_xface->mac_rrc_meas_ind     = mac_rrc_meas_ind;
  //  Rrc_xface->get_rrc_status       = get_rrc_status;

  //Rrc_xface->rrc_get_status = ...

  //  Mac_rlc_xface->mac_out_of_sync_ind=mac_out_of_sync_ind;

#ifndef NO_RRM
  //  Rrc_xface->fn_rrc=fn_rrc;
#endif
  //  LOG_D(RRC, "[RRC]INIT_GLOBAL_PARAM: Mac_rlc_xface %p, rrc_rlc_register %p,rlcrrc_data_ind%p\n",Mac_rlc_xface,Mac_rlc_xface->rrc_rlc_register_rrc,rlcrrc_data_ind);
  /*
   if((Mac_rlc_xface==NULL) || (Mac_rlc_xface->rrc_rlc_register_rrc==NULL) ||
   (rlcrrc_data_ind==NULL)) {
   LOG_E(RRC,"Data structured is not initialized \n");
   return -1;
   }
   */
  rrc_rlc_register_rrc (rrc_data_ind, NULL); //register with rlc

  DCCH_LCHAN_DESC.transport_block_size = 4;
  DCCH_LCHAN_DESC.max_transport_blocks = 16;
  DCCH_LCHAN_DESC.Delay_class = 1;
  DTCH_DL_LCHAN_DESC.transport_block_size = 52;
  DTCH_DL_LCHAN_DESC.max_transport_blocks = 20;
  DTCH_DL_LCHAN_DESC.Delay_class = 1;
  DTCH_UL_LCHAN_DESC.transport_block_size = 52;
  DTCH_UL_LCHAN_DESC.max_transport_blocks = 20;
  DTCH_UL_LCHAN_DESC.Delay_class = 1;

  Rlc_info_um.rlc_mode = RLC_MODE_UM;
  Rlc_info_um.rlc.rlc_um_info.timer_reordering = 5;
  Rlc_info_um.rlc.rlc_um_info.sn_field_length = 10;
  Rlc_info_um.rlc.rlc_um_info.is_mXch = 0;
  //Rlc_info_um.rlc.rlc_um_info.sdu_discard_mode=16;

  Rlc_info_am_config.rlc_mode = RLC_MODE_AM;
  Rlc_info_am_config.rlc.rlc_am_info.max_retx_threshold = 50;
  Rlc_info_am_config.rlc.rlc_am_info.poll_pdu = 8;
  Rlc_info_am_config.rlc.rlc_am_info.poll_byte = 1000;
  Rlc_info_am_config.rlc.rlc_am_info.t_poll_retransmit = 15;
  Rlc_info_am_config.rlc.rlc_am_info.t_reordering = 50;
  Rlc_info_am_config.rlc.rlc_am_info.t_status_prohibit = 10;
#ifndef NO_RRM

  if (L3_xface_init ()) {
    return (-1);
  }

#endif

  return 0;
}

#ifndef NO_RRM
//-----------------------------------------------------------------------------
int
L3_xface_init(
  void
)
//-----------------------------------------------------------------------------
{

  int ret = 0;

#ifdef USER_MODE

  int sock;
  LOG_D(RRC, "[L3_XFACE] init de l'interface \n");

  if (open_socket (&S_rrc, RRC_RRM_SOCK_PATH, RRM_RRC_SOCK_PATH, 0) == -1) {
    return (-1);
  }

  if (S_rrc.s == -1) {
    return (-1);
  }

  socket_setnonblocking (S_rrc.s);
  msg ("Interface Connected... RRM-RRC\n");
  return 0;

#else

  ret=rtf_create(RRC2RRM_FIFO,32768);

  if (ret < 0) {
    msg("[openair][MAC][INIT] Cannot create RRC2RRM fifo %d (ERROR %d)\n",RRC2RRM_FIFO,ret);
    return(-1);
  } else {
    msg("[openair][MAC][INIT] Created RRC2RRM fifo %d\n",RRC2RRM_FIFO);
    rtf_reset(RRC2RRM_FIFO);
  }

  ret=rtf_create(RRM2RRC_FIFO,32768);

  if (ret < 0) {
    msg("[openair][MAC][INIT] Cannot create RRM2RRC fifo %d (ERROR %d)\n",RRM2RRC_FIFO,ret);
    return(-1);
  } else {
    msg("[openair][MAC][INIT] Created RRC2RRM fifo %d\n",RRM2RRC_FIFO);
    rtf_reset(RRM2RRC_FIFO);
  }

  return(0);

#endif
}
#endif

//-----------------------------------------------------------------------------
void
rrc_config_buffer(
  SRB_INFO* Srb_info,
  uint8_t Lchan_type,
  uint8_t Role
)
//-----------------------------------------------------------------------------
{

  Srb_info->Rx_buffer.payload_size = 0;
  Srb_info->Tx_buffer.payload_size = 0;
}

/*------------------------------------------------------------------------------*/
void
openair_rrc_top_init(
  int eMBMS_active,
  char* uecap_xer,
  uint8_t cba_group_active,
  uint8_t HO_active
)
//-----------------------------------------------------------------------------
{

  module_id_t         module_id;
  OAI_UECapability_t *UECap     = NULL;
  int                 CC_id;

  /* for no gcc warnings */
  (void)CC_id;

  LOG_D(RRC, "[OPENAIR][INIT] Init function start: NB_UE_INST=%d, NB_eNB_INST=%d\n", NB_UE_INST, NB_eNB_INST);

  if (NB_UE_INST > 0) {
    UE_rrc_inst = (UE_RRC_INST*) malloc16(NB_UE_INST*sizeof(UE_RRC_INST));
    memset (UE_rrc_inst, 0, NB_UE_INST * sizeof(UE_RRC_INST));
    LOG_D(RRC, "ALLOCATE %d Bytes for UE_RRC_INST @ %p\n", (unsigned int)(NB_UE_INST*sizeof(UE_RRC_INST)), UE_rrc_inst);

    // fill UE capability
    UECap = fill_ue_capability (uecap_xer);

    for (module_id = 0; module_id < NB_UE_INST; module_id++) {
      UE_rrc_inst[module_id].UECap = UECap;
      UE_rrc_inst[module_id].UECapability = UECap->sdu;
      UE_rrc_inst[module_id].UECapability_size = UECap->sdu_size;
    }

#ifdef Rel10
    LOG_I(RRC,"[UE] eMBMS active state is %d \n", eMBMS_active);

    for (module_id=0; module_id<NB_UE_INST; module_id++) {
      UE_rrc_inst[module_id].MBMS_flag = (uint8_t)eMBMS_active;
    }

#endif
  } else {
    UE_rrc_inst = NULL;
  }

  if (NB_eNB_INST > 0) {
    eNB_rrc_inst = (eNB_RRC_INST*) malloc16(NB_eNB_INST*sizeof(eNB_RRC_INST));
    memset (eNB_rrc_inst, 0, NB_eNB_INST * sizeof(eNB_RRC_INST));
    LOG_I(RRC,"[eNB] handover active state is %d \n", HO_active);

    for (module_id=0; module_id<NB_eNB_INST; module_id++) {
      eNB_rrc_inst[module_id].HO_flag   = (uint8_t)HO_active;
    }

#ifdef Rel10
    LOG_I(RRC,"[eNB] eMBMS active state is %d \n", eMBMS_active);

    for (module_id=0; module_id<NB_eNB_INST; module_id++) {
      for (CC_id = 0; CC_id < MAX_NUM_CCs; CC_id++) {
        eNB_rrc_inst[module_id].carrier[CC_id].MBMS_flag = (uint8_t)eMBMS_active;
      }
    }

#endif
#ifdef CBA

    for (module_id=0; module_id<NB_eNB_INST; module_id++) {
      for (CC_id = 0; CC_id < MAX_NUM_CCs; CC_id++) {
        eNB_rrc_inst[module_id].carrier[CC_id].num_active_cba_groups = cba_group_active;
      }
    }

#endif
#ifdef LOCALIZATION
    /* later set this from xml or enb.config file*/
    struct timeval ts; // time struct
    gettimeofday(&ts, NULL); // get the current epoch timestamp

    for (module_id=0; module_id<NB_eNB_INST; module_id++) {
      eNB_rrc_inst[module_id].reference_timestamp_ms = ts.tv_sec * 1000 + ts.tv_usec / 1000;
      initialize(&eNB_rrc_inst[module_id].loc_list);
      eNB_rrc_inst[module_id].loc_type=0;
      eNB_rrc_inst[module_id].aggregation_period_ms = 5000;
    }

#endif
    LOG_D(RRC,
          "ALLOCATE %d Bytes for eNB_RRC_INST @ %p\n", (unsigned int)(NB_eNB_INST*sizeof(eNB_RRC_INST)), eNB_rrc_inst);
  } else {
    eNB_rrc_inst = NULL;
  }

#ifndef NO_RRM
#ifndef USER_MODE

  Header_buf=(char*)malloc16(sizeof(msg_head_t));
  Data=(char*)malloc16(2400);
  Header_read_idx=0;
  Data_read_idx=0;
  Header_size=sizeof(msg_head_t);

#endif //NO_RRM
  Data_to_read = 0;
#endif //USER_MODE
}

//-----------------------------------------------------------------------------
void
rrc_top_cleanup(
  void
)
//-----------------------------------------------------------------------------
{

  if (NB_UE_INST > 0) {
    free (UE_rrc_inst);
  }

  if (NB_eNB_INST > 0) {
    free (eNB_rrc_inst);

  }
}


//-----------------------------------------------------------------------------
void
rrc_t310_expiration(
  const protocol_ctxt_t* const ctxt_pP,
  const uint8_t                 eNB_index
)
//-----------------------------------------------------------------------------
{

  if (UE_rrc_inst[ctxt_pP->module_id].Info[eNB_index].State != RRC_CONNECTED) {
    LOG_D(RRC, "Timer 310 expired, going to RRC_IDLE\n");
    UE_rrc_inst[ctxt_pP->module_id].Info[eNB_index].State = RRC_IDLE;
    UE_rrc_inst[ctxt_pP->module_id].Info[eNB_index].UE_index = 0xffff;
    UE_rrc_inst[ctxt_pP->module_id].Srb0[eNB_index].Rx_buffer.payload_size = 0;
    UE_rrc_inst[ctxt_pP->module_id].Srb0[eNB_index].Tx_buffer.payload_size = 0;
    UE_rrc_inst[ctxt_pP->module_id].Srb1[eNB_index].Srb_info.Rx_buffer.payload_size = 0;
    UE_rrc_inst[ctxt_pP->module_id].Srb1[eNB_index].Srb_info.Tx_buffer.payload_size = 0;

    if (UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Active == 1) {
      msg ("[RRC Inst %d] eNB_index %d, Remove RB %d\n ", ctxt_pP->module_id, eNB_index,
           UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Srb_info.Srb_id);
      rrc_pdcp_config_req (ctxt_pP,
                           SRB_FLAG_YES,
                           CONFIG_ACTION_REMOVE,
                           UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Srb_info.Srb_id,
                           0);
      rrc_rlc_config_req (ctxt_pP,
                          SRB_FLAG_YES,
                          MBMS_FLAG_NO,
                          CONFIG_ACTION_REMOVE,
                          UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Srb_info.Srb_id,
                          Rlc_info_um);
      UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Active = 0;
      UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Status = IDLE;
      UE_rrc_inst[ctxt_pP->module_id].Srb2[eNB_index].Next_check_frame = 0;
    }
  } else { // Restablishment procedure
    LOG_D(RRC, "Timer 310 expired, trying RRCRestablishment ...\n");
  }
}

//-----------------------------------------------------------------------------
RRC_status_t
rrc_rx_tx(
  protocol_ctxt_t* const ctxt_pP,
  const uint8_t      enb_indexP,
  const int          CC_id
)
//-----------------------------------------------------------------------------
{
  //uint8_t        UE_id;
  int32_t        current_timestamp_ms, ref_timestamp_ms;
  struct timeval ts;
  struct rrc_eNB_ue_context_s   *ue_context_p = NULL,*ue_to_be_removed = NULL;

#ifdef LOCALIZATION
  double                         estimated_distance;
  protocol_ctxt_t                ctxt;
#endif
  VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_IN);

  if(ctxt_pP->enb_flag == ENB_FLAG_NO) {
    // check timers

    if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T300_active == 1) {
      if ((UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T300_cnt % 10) == 0)
        LOG_D(RRC,
              "[UE %d][RAPROC] Frame %d T300 Count %d ms\n", ctxt_pP->module_id, ctxt_pP->frame, UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T300_cnt);

      if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T300_cnt
          == T300[UE_rrc_inst[ctxt_pP->module_id].sib2[enb_indexP]->ue_TimersAndConstants.t300]) {
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T300_active = 0;
        // ALLOW CCCH to be used
        UE_rrc_inst[ctxt_pP->module_id].Srb0[enb_indexP].Tx_buffer.payload_size = 0;
        rrc_ue_generate_RRCConnectionRequest (ctxt_pP, enb_indexP);
        VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_OUT);
        return (RRC_ConnSetup_failed);
      }

      UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T300_cnt++;
    }

    if ((UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].SIStatus&2)>0) {
      if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].N310_cnt
          == N310[UE_rrc_inst[ctxt_pP->module_id].sib2[enb_indexP]->ue_TimersAndConstants.n310]) {
	LOG_I(RRC,"Activating T310\n");
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_active = 1;
      }
    } else { // in case we have not received SIB2 yet
      /*      if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].N310_cnt == 100) {
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].N310_cnt = 0;

	}*/
      VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_OUT);
      return RRC_OK;
    }

    if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_active == 1) {
      if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].N311_cnt
          == N311[UE_rrc_inst[ctxt_pP->module_id].sib2[enb_indexP]->ue_TimersAndConstants.n311]) {
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_active = 0;
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].N311_cnt = 0;
      }

      if ((UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_cnt % 10) == 0) {
        LOG_D(RRC, "[UE %d] Frame %d T310 Count %d ms\n", ctxt_pP->module_id, ctxt_pP->frame, UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_cnt);
      }

      if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_cnt    == T310[UE_rrc_inst[ctxt_pP->module_id].sib2[enb_indexP]->ue_TimersAndConstants.t310]) {
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_active = 0;
        rrc_t310_expiration (ctxt_pP, enb_indexP);
        VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_OUT);
	LOG_I(RRC,"Returning RRC_PHY_RESYNCH: T310 expired\n"); 
        return RRC_PHY_RESYNCH;
      }

      UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T310_cnt++;
    }

    if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T304_active==1) {
      if ((UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T304_cnt % 10) == 0)
        LOG_D(RRC,"[UE %d][RAPROC] Frame %d T304 Count %d ms\n",ctxt_pP->module_id,ctxt_pP->frame,
              UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T304_cnt);

      if (UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T304_cnt == 0) {
        UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T304_active = 0;
        UE_rrc_inst[ctxt_pP->module_id].HandoverInfoUe.measFlag = 1;
        LOG_E(RRC,"[UE %d] Handover failure..initiating connection re-establishment procedure... \n");
        //Implement 36.331, section 5.3.5.6 here
        VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_OUT);
        return(RRC_Handover_failed);
      }

      UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].T304_cnt--;
    }

    // Layer 3 filtering of RRC measurements
    if (UE_rrc_inst[ctxt_pP->module_id].QuantityConfig[0] != NULL) {
      ue_meas_filtering(ctxt_pP,enb_indexP);
    }

    ue_measurement_report_triggering(ctxt_pP,enb_indexP);

    if (UE_rrc_inst[ctxt_pP->module_id].Info[0].handoverTarget > 0) {
      LOG_I(RRC,"[UE %d] Frame %d : RRC handover initiated\n", ctxt_pP->module_id, ctxt_pP->frame);
    }

    if((UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].State == RRC_HO_EXECUTION)   &&
        (UE_rrc_inst[ctxt_pP->module_id].HandoverInfoUe.targetCellId != 0xFF)) {
      UE_rrc_inst[ctxt_pP->module_id].Info[enb_indexP].State= RRC_IDLE;
      VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_OUT);
      return(RRC_HO_STARTED);
    }

  } else { // eNB
    check_handovers(ctxt_pP);
    // counetr, and get the value and aggregate

    // check for UL failure
    RB_FOREACH(ue_context_p, rrc_ue_tree_s, &(eNB_rrc_inst[ctxt_pP->module_id].rrc_ue_head)) {
      if (ue_context_p->ue_context.ul_failure_timer>0) {
	ue_context_p->ue_context.ul_failure_timer++;
	if (ue_context_p->ue_context.ul_failure_timer >= 20000) {
	  // remove UE after 20 seconds after MAC has indicated UL failure
	  LOG_I(RRC,"Removing UE %x instance\n",ue_context_p->ue_context.rnti);
	  ue_to_be_removed = ue_context_p;
	  break;
	}
      }
      if (ue_context_p->ue_context.ue_release_timer>0) {
	ue_context_p->ue_context.ue_release_timer++;
	if (ue_context_p->ue_context.ue_release_timer >= 100) {
	  // remove UE after 10 frames after RRCConnectionRelease is triggered
	  LOG_I(RRC,"Removing UE %x instance\n",ue_context_p->ue_context.rnti);
	  ue_to_be_removed = ue_context_p;
	  break;
	}
      }
    }
    if (ue_to_be_removed)
      rrc_eNB_free_UE(ctxt_pP->module_id,ue_to_be_removed);

#ifdef RRC_LOCALIZATION

    /* for the localization, only primary CC_id might be relevant*/
    gettimeofday(&ts, NULL);
    current_timestamp_ms = ts.tv_sec * 1000 + ts.tv_usec / 1000;
    ref_timestamp_ms = eNB_rrc_inst[ctxt_pP->module_id].reference_timestamp_ms;
    RB_FOREACH(ue_context_p, rrc_ue_tree_s, &(eNB_rrc_inst[ctxt_pP->module_id].rrc_ue_head)) {
      ctxt = *ctxt_pP;
      ctxt.rnti = ue_context_p->ue_context.rnti;
      estimated_distance = rrc_get_estimated_ue_distance(
                             &ctxt,
                             CC_id,
                             eNB_rrc_inst[ctxt_pP->module_id].loc_type);

      if ((current_timestamp_ms - ref_timestamp_ms > eNB_rrc_inst[ctxt_pP->module_id].aggregation_period_ms) &&
          estimated_distance != -1) {
        LOG_D(LOCALIZE, " RRC [UE/id %d -> eNB/id %d] timestamp %d frame %d estimated r = %f\n",
              ctxt.rnti,
              ctxt_pP->module_id,
              current_timestamp_ms,
              ctxt_pP->frame,
              estimated_distance);
        LOG_D(LOCALIZE, " RRC status %d\n", ue_context_p->ue_context.Status);
        push_front(&eNB_rrc_inst[ctxt_pP->module_id].loc_list,
                   estimated_distance);
        eNB_rrc_inst[ctxt_pP->module_id].reference_timestamp_ms = current_timestamp_ms;
      }
    }

#endif
    (void)ts; /* remove gcc warning "unused variable" */
    (void)ref_timestamp_ms; /* remove gcc warning "unused variable" */
    (void)current_timestamp_ms; /* remove gcc warning "unused variable" */
  }

  VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_RRC_RX_TX,VCD_FUNCTION_OUT);
  return (RRC_OK);
}

//-----------------------------------------------------------------------------
long
binary_search_int(
  int elements[],
  long numElem,
  int value
)
//-----------------------------------------------------------------------------
{
  long first, last, middle, search = -1;
  first = 0;
  last = numElem-1;
  middle = (first+last)/2;

  if(value < elements[0]) {
    return first;
  }

  if(value > elements[last]) {
    return last;
  }

  while (first <= last) {
    if (elements[middle] < value) {
      first = middle+1;
    } else if (elements[middle] == value) {
      search = middle+1;
      break;
    } else {
      last = middle -1;
    }

    middle = (first+last)/2;
  }

  if (first > last) {
    LOG_E(RRC,"Error in binary search!");
  }

  return search;
}

/* This is a binary search routine which operates on an array of floating
   point numbers and returns the index of the range the value lies in
   Used for RSRP and RSRQ measurement mapping. Can potentially be used for other things
*/
//-----------------------------------------------------------------------------
long
binary_search_float(
  float elements[],
  long numElem,
  float value
)
//-----------------------------------------------------------------------------
{
  long first, last, middle;
  first = 0;
  last = numElem-1;
  middle = (first+last)/2;

  if(value <= elements[0]) {
    return first;
  }

  if(value >= elements[last]) {
    return last;
  }

  while (last - first > 1) {
    if (elements[middle] > value) {
      last = middle;
    } else {
      first = middle;
    }

    middle = (first+last)/2;
  }

  if (first < 0 || first >= numElem) {
    LOG_E(RRC,"\n Error in binary search float!");
  }

  return first;
}