eNB_scheduler_dlsch.c

/*
 * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The OpenAirInterface Software Alliance licenses this file to You under
 * the OAI Public License, Version 1.1  (the "License"); you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.openairinterface.org/?page_id=698
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *-------------------------------------------------------------------------------
 * For more information about the OpenAirInterface (OAI) Software Alliance:
 *      contact@openairinterface.org
 */

/*! \file eNB_scheduler_dlsch.c
 * \brief procedures related to eNB for the DLSCH transport channel
 * \author  Navid Nikaein and Raymond Knopp
 * \date 2010 - 2014
 * \email: navid.nikaein@eurecom.fr
 * \version 1.0
 * @ingroup _mac

 */

#define _GNU_SOURCE

#include "LAYER2/MAC/mac.h"
#include "LAYER2/MAC/mac_proto.h"
#include "LAYER2/MAC/mac_extern.h"
#include "common/utils/LOG/log.h"
#include "common/utils/LOG/vcd_signal_dumper.h"
#include "UTIL/OPT/opt.h"
#include "OCG.h"
#include "OCG_extern.h"
#include "PHY/LTE_TRANSPORT/transport_common_proto.h"

#include "RRC/LTE/rrc_extern.h"
#include "RRC/L2_INTERFACE/openair_rrc_L2_interface.h"
/************************************************/
//#include "RRC/LTE/rrc_eNB_UE_context.h"
//#include "RRC/LTE/rrc_defs.h"
/************************************************/

//#include "LAYER2/MAC/pre_processor.c"
#include "pdcp.h"

#include "SIMULATION/TOOLS/sim.h"	// for taus

#include "assertions.h"

#if defined(ENABLE_ITTI)
#include "intertask_interface.h"
#endif

#include <dlfcn.h>

#include "T.h"

#define ENABLE_MAC_PAYLOAD_DEBUG
//#define DEBUG_eNB_SCHEDULER 1

#include "common/ran_context.h"
extern RAN_CONTEXT_t RC;
extern uint8_t nfapi_mode;

//------------------------------------------------------------------------------
void
add_ue_dlsch_info(module_id_t module_idP,
                  int CC_id,
                  int UE_id, sub_frame_t subframeP, UE_DLSCH_STATUS status)
//------------------------------------------------------------------------------
{
  //LOG_D(MAC, "%s(module_idP:%d, CC_id:%d, UE_id:%d, subframeP:%d, status:%d) serving_num:%d rnti:%x\n", __FUNCTION__, module_idP, CC_id, UE_id, subframeP, status, eNB_dlsch_info[module_idP][CC_id][UE_id].serving_num, UE_RNTI(module_idP,UE_id));

  eNB_dlsch_info[module_idP][CC_id][UE_id].rnti =
          UE_RNTI(module_idP, UE_id);
  //  eNB_dlsch_info[module_idP][CC_id][ue_mod_idP].weight           = weight;
  eNB_dlsch_info[module_idP][CC_id][UE_id].subframe = subframeP;
  eNB_dlsch_info[module_idP][CC_id][UE_id].status = status;

  eNB_dlsch_info[module_idP][CC_id][UE_id].serving_num++;

}

//------------------------------------------------------------------------------
int
schedule_next_dlue(module_id_t module_idP, int CC_id,
                   sub_frame_t subframeP)
//------------------------------------------------------------------------------
{

  int next_ue;
  UE_list_t *UE_list = &RC.mac[module_idP]->UE_list;

  for (next_ue = UE_list->head; next_ue >= 0;
       next_ue = UE_list->next[next_ue]) {
    if (eNB_dlsch_info[module_idP][CC_id][next_ue].status ==
        S_DL_WAITING) {
      return next_ue;
    }
  }

  for (next_ue = UE_list->head; next_ue >= 0;
       next_ue = UE_list->next[next_ue]) {
    if (eNB_dlsch_info[module_idP][CC_id][next_ue].status == S_DL_BUFFERED) {
      eNB_dlsch_info[module_idP][CC_id][next_ue].status = S_DL_WAITING;
    }
  }

  return (-1);        //next_ue;

}

//------------------------------------------------------------------------------
int
generate_dlsch_header(unsigned char *mac_header,
                      unsigned char num_sdus,
                      unsigned short *sdu_lengths,
                      unsigned char *sdu_lcids,
                      unsigned char drx_cmd,
                      unsigned short timing_advance_cmd,
                      unsigned char *ue_cont_res_id,
                      unsigned char short_padding,
                      unsigned short post_padding)
//------------------------------------------------------------------------------
{

  SCH_SUBHEADER_FIXED *mac_header_ptr = (SCH_SUBHEADER_FIXED *) mac_header;
  uint8_t first_element = 0, last_size = 0, i;
  uint8_t mac_header_control_elements[16], *ce_ptr;

  ce_ptr = &mac_header_control_elements[0];

  // compute header components

  if ((short_padding == 1) || (short_padding == 2)) {
    mac_header_ptr->R = 0;
    mac_header_ptr->E = 0;
    mac_header_ptr->LCID = SHORT_PADDING;
    first_element = 1;
    last_size = 1;
  }

  if (short_padding == 2) {
    mac_header_ptr->E = 1;
    mac_header_ptr++;
    mac_header_ptr->R = 0;
    mac_header_ptr->E = 0;
    mac_header_ptr->LCID = SHORT_PADDING;
    last_size = 1;
  }

  if (drx_cmd != 255) {
    if (first_element > 0) {
      mac_header_ptr->E = 1;
      mac_header_ptr++;
    } else {
      first_element = 1;
    }

    mac_header_ptr->R = 0;
    mac_header_ptr->E = 0;
    mac_header_ptr->LCID = DRX_CMD;
    last_size = 1;
  }

  if (timing_advance_cmd != 31) {
    if (first_element > 0) {
      mac_header_ptr->E = 1;
      mac_header_ptr++;
    } else {
      first_element = 1;
    }

    mac_header_ptr->R = 0;
    mac_header_ptr->E = 0;
    mac_header_ptr->LCID = TIMING_ADV_CMD;
    last_size = 1;
    //    msg("last_size %d,mac_header_ptr %p\n",last_size,mac_header_ptr);
    ((TIMING_ADVANCE_CMD *) ce_ptr)->R = 0;
    AssertFatal(timing_advance_cmd < 64,
                "timing_advance_cmd %d > 63\n", timing_advance_cmd);
    ((TIMING_ADVANCE_CMD *) ce_ptr)->TA = timing_advance_cmd;    //(timing_advance_cmd+31)&0x3f;
    LOG_D(MAC, "timing advance =%d (%d)\n", timing_advance_cmd,
          ((TIMING_ADVANCE_CMD *) ce_ptr)->TA);
    ce_ptr += sizeof(TIMING_ADVANCE_CMD);
    //msg("offset %d\n",ce_ptr-mac_header_control_elements);
  }

  if (ue_cont_res_id) {
    if (first_element > 0) {
      mac_header_ptr->E = 1;
      /*
	printf("[eNB][MAC] last subheader : %x (R%d,E%d,LCID%d)\n",*(unsigned char*)mac_header_ptr,
	((SCH_SUBHEADER_FIXED *)mac_header_ptr)->R,
	((SCH_SUBHEADER_FIXED *)mac_header_ptr)->E,
	((SCH_SUBHEADER_FIXED *)mac_header_ptr)->LCID);
      */
      mac_header_ptr++;
    } else {
      first_element = 1;
    }

    mac_header_ptr->R = 0;
    mac_header_ptr->E = 0;
    mac_header_ptr->LCID = UE_CONT_RES;
    last_size = 1;

    LOG_T(MAC,
          "[eNB ][RAPROC] Generate contention resolution msg: %x.%x.%x.%x.%x.%x\n",
          ue_cont_res_id[0], ue_cont_res_id[1], ue_cont_res_id[2],
          ue_cont_res_id[3], ue_cont_res_id[4], ue_cont_res_id[5]);

    memcpy(ce_ptr, ue_cont_res_id, 6);
    ce_ptr += 6;
    // msg("(cont_res) : offset %d\n",ce_ptr-mac_header_control_elements);
  }
  //msg("last_size %d,mac_header_ptr %p\n",last_size,mac_header_ptr);

  for (i = 0; i < num_sdus; i++) {
    LOG_T(MAC, "[eNB] Generate DLSCH header num sdu %d len sdu %d\n",
          num_sdus, sdu_lengths[i]);

    if (first_element > 0) {
      mac_header_ptr->E = 1;
      /*msg("last subheader : %x (R%d,E%d,LCID%d)\n",*(unsigned char*)mac_header_ptr,
	((SCH_SUBHEADER_FIXED *)mac_header_ptr)->R,
	((SCH_SUBHEADER_FIXED *)mac_header_ptr)->E,
	((SCH_SUBHEADER_FIXED *)mac_header_ptr)->LCID);
      */
      mac_header_ptr += last_size;
      //msg("last_size %d,mac_header_ptr %p\n",last_size,mac_header_ptr);
    } else {
      first_element = 1;
    }

    if (sdu_lengths[i] < 128) {
      ((SCH_SUBHEADER_SHORT *) mac_header_ptr)->R = 0;
      ((SCH_SUBHEADER_SHORT *) mac_header_ptr)->E = 0;
      ((SCH_SUBHEADER_SHORT *) mac_header_ptr)->F = 0;
      ((SCH_SUBHEADER_SHORT *) mac_header_ptr)->LCID = sdu_lcids[i];
      ((SCH_SUBHEADER_SHORT *) mac_header_ptr)->L = (unsigned char) sdu_lengths[i];
      last_size = 2;
    } else {
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->R = 0;
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->E = 0;
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->F = 1;
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->LCID = sdu_lcids[i];
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->L_MSB = ((unsigned short) sdu_lengths[i] >> 8) & 0x7f;
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->L_LSB = (unsigned short) sdu_lengths[i] & 0xff;
      ((SCH_SUBHEADER_LONG *) mac_header_ptr)->padding = 0x00;
      last_size = 3;
#ifdef DEBUG_HEADER_PARSING
      LOG_D(MAC,
        "[eNB] generate long sdu, size %x (MSB %x, LSB %x)\n",
        sdu_lengths[i],
        ((SCH_SUBHEADER_LONG *) mac_header_ptr)->L_MSB,
        ((SCH_SUBHEADER_LONG *) mac_header_ptr)->L_LSB);
#endif
    }
  }

  /*

    printf("last_size %d,mac_header_ptr %p\n",last_size,mac_header_ptr);

    printf("last subheader : %x (R%d,E%d,LCID%d)\n",*(unsigned char*)mac_header_ptr,
    ((SCH_SUBHEADER_FIXED *)mac_header_ptr)->R,
    ((SCH_SUBHEADER_FIXED *)mac_header_ptr)->E,
    ((SCH_SUBHEADER_FIXED *)mac_header_ptr)->LCID);


    if (((SCH_SUBHEADER_FIXED*)mac_header_ptr)->LCID < UE_CONT_RES) {
    if (((SCH_SUBHEADER_SHORT*)mac_header_ptr)->F == 0)
    printf("F = 0, sdu len (L field) %d\n",(((SCH_SUBHEADER_SHORT*)mac_header_ptr)->L));
    else
    printf("F = 1, sdu len (L field) %d\n",(((SCH_SUBHEADER_LONG*)mac_header_ptr)->L));
    }
  */
  if (post_padding > 0) {    // we have lots of padding at the end of the packet
    mac_header_ptr->E = 1;
    mac_header_ptr += last_size;
    // add a padding element
    mac_header_ptr->R = 0;
    mac_header_ptr->E = 0;
    mac_header_ptr->LCID = SHORT_PADDING;
    mac_header_ptr++;
  } else {            // no end of packet padding
    // last SDU subhead is of fixed type (sdu length implicitly to be computed at UE)
    mac_header_ptr++;
  }

  //msg("After subheaders %d\n",(uint8_t*)mac_header_ptr - mac_header);

  if ((ce_ptr - mac_header_control_elements) > 0) {
    // printf("Copying %d bytes for control elements\n",ce_ptr-mac_header_control_elements);
    memcpy((void *) mac_header_ptr, mac_header_control_elements,
           ce_ptr - mac_header_control_elements);
    mac_header_ptr +=
            (unsigned char) (ce_ptr - mac_header_control_elements);
  }
  //msg("After CEs %d\n",(uint8_t*)mac_header_ptr - mac_header);

  return ((unsigned char *) mac_header_ptr - mac_header);
}

//------------------------------------------------------------------------------
void
set_ul_DAI(int module_idP, int UE_idP, int CC_idP, int frameP,
           int subframeP)
//------------------------------------------------------------------------------
{

  eNB_MAC_INST *eNB = RC.mac[module_idP];
  UE_list_t *UE_list = &eNB->UE_list;
  unsigned char DAI;
  COMMON_channels_t *cc = &eNB->common_channels[CC_idP];
  if (cc->tdd_Config != NULL) {    //TDD
    DAI = (UE_list->UE_template[CC_idP][UE_idP].DAI - 1) & 3;
    LOG_D(MAC,
          "[eNB %d] CC_id %d Frame %d, subframe %d: DAI %d for UE %d\n",
          module_idP, CC_idP, frameP, subframeP, DAI, UE_idP);
    // Save DAI for Format 0 DCI

    switch (cc->tdd_Config->subframeAssignment) {
      case 0:
        //      if ((subframeP==0)||(subframeP==1)||(subframeP==5)||(subframeP==6))
        break;

      case 1:
        switch (subframeP) {
        case 0:
        case 1:
          UE_list->UE_template[CC_idP][UE_idP].DAI_ul[7] = DAI;
        break;

        case 4:
          UE_list->UE_template[CC_idP][UE_idP].DAI_ul[8] = DAI;
          break;

        case 5:
        case 6:
          UE_list->UE_template[CC_idP][UE_idP].DAI_ul[2] = DAI;
          break;

        case 9:
          UE_list->UE_template[CC_idP][UE_idP].DAI_ul[3] = DAI;
          break;
        }
        break;

      case 2:
        //      if ((subframeP==3)||(subframeP==8))
        //  UE_list->UE_template[CC_idP][UE_idP].DAI_ul = DAI;
        break;

      case 3:

        //if ((subframeP==6)||(subframeP==8)||(subframeP==0)) {
        //  LOG_D(MAC,"schedule_ue_spec: setting UL DAI to %d for subframeP %d => %d\n",DAI,subframeP, ((subframeP+8)%10)>>1);
        //  UE_list->UE_template[CC_idP][UE_idP].DAI_ul[((subframeP+8)%10)>>1] = DAI;
        //}
        switch (subframeP) {
          case 5:
          case 6:
          case 1:
            UE_list->UE_template[CC_idP][UE_idP].DAI_ul[2] = DAI;
            break;

          case 7:
          case 8:
            UE_list->UE_template[CC_idP][UE_idP].DAI_ul[3] = DAI;
            break;

          case 9:
          case 0:
            UE_list->UE_template[CC_idP][UE_idP].DAI_ul[4] = DAI;
            break;

          default:
            break;
        }

        break;

      case 4:
        //      if ((subframeP==8)||(subframeP==9))
        //  UE_list->UE_template[CC_idP][UE_idP].DAI_ul = DAI;
        break;

      case 5:
        //      if (subframeP==8)
        //  UE_list->UE_template[CC_idP][UE_idP].DAI_ul = DAI;
        break;

      case 6:
        //      if ((subframeP==1)||(subframeP==4)||(subframeP==6)||(subframeP==9))
        //  UE_list->UE_template[CC_idP][UE_idP].DAI_ul = DAI;
        break;

      default:
        break;
    }
  }
}

//------------------------------------------------------------------------------
void
schedule_dlsch(module_id_t module_idP, frame_t frameP, sub_frame_t subframeP, int *mbsfn_flag) {

  int i = 0;
  slice_info_t *sli = &RC.mac[module_idP]->slice_info;
  memset(sli->rballoc_sub, 0, sizeof(sli->rballoc_sub));

  for (i = 0; i < sli->n_dl; i++) {
    // Run each enabled slice-specific schedulers one by one
    sli->dl[i].sched_cb(module_idP, i, frameP, subframeP, mbsfn_flag/*, dl_info*/);
  }

}

// changes to pre-processor for eMTC

//------------------------------------------------------------------------------
void
schedule_ue_spec(module_id_t module_idP, int slice_idxP,
                 frame_t frameP, sub_frame_t subframeP, int *mbsfn_flag)
//------------------------------------------------------------------------------
{
  int CC_id;
  int UE_id;
  int aggregation;
  mac_rlc_status_resp_t rlc_status;
  int ta_len = 0;
  unsigned char sdu_lcids[NB_RB_MAX];
  int lcid, offset, num_sdus = 0;
  int nb_rb, nb_rb_temp, nb_available_rb;
  uint16_t sdu_lengths[NB_RB_MAX];
  int TBS, j, rnti, padding = 0, post_padding = 0;
  unsigned char dlsch_buffer[MAX_DLSCH_PAYLOAD_BYTES];
  int round = 0;
  int harq_pid = 0;
  eNB_UE_STATS *eNB_UE_stats = NULL;
  int sdu_length_total = 0;

  eNB_MAC_INST *eNB = RC.mac[module_idP];
  COMMON_channels_t *cc = eNB->common_channels;
  UE_list_t *UE_list = &eNB->UE_list;
  int continue_flag = 0;
  int32_t normalized_rx_power, target_rx_power;
  int tpc = 1;
  UE_sched_ctrl *ue_sched_ctl;
  int mcs;
  int i;
  int min_rb_unit[NFAPI_CC_MAX];
  int N_RB_DL[NFAPI_CC_MAX];
  int total_nb_available_rb[NFAPI_CC_MAX];
  int N_RBG[NFAPI_CC_MAX];
  nfapi_dl_config_request_body_t *dl_req;
  nfapi_dl_config_request_pdu_t *dl_config_pdu;
  int tdd_sfa;
  int ta_update;
  int header_length_last;
  int header_length_total;

  rrc_eNB_ue_context_t *ue_contextP; // added by LA

  start_meas(&eNB->schedule_dlsch);
  VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_SCHEDULE_DLSCH, VCD_FUNCTION_IN);

  // for TDD: check that we have to act here, otherwise return
  if (cc[0].tdd_Config) {
    tdd_sfa = cc[0].tdd_Config->subframeAssignment;
    switch (subframeP) {
      case 0:
        // always continue
        break;
      case 1:
        return;
        break;
      case 2:
        return;
        break;
      case 3:
        if ((tdd_sfa != 2) && (tdd_sfa != 5))
          return;
        break;
      case 4:
        if ((tdd_sfa != 1) && (tdd_sfa != 2) && (tdd_sfa != 4)
            && (tdd_sfa != 5))
          return;
        break;
      case 5:
        break;
      case 6:
      case 7:
        if ((tdd_sfa != 3) && (tdd_sfa != 4) && (tdd_sfa != 5))
          return;
        break;
      case 8:
        if ((tdd_sfa != 2) && (tdd_sfa != 3) && (tdd_sfa != 4)
            && (tdd_sfa != 5))
          return;
        break;
      case 9:
        if (tdd_sfa == 0)
          return;
        break;
    }
  }
  //weight = get_ue_weight(module_idP,UE_id);
  aggregation = 2;
  for (CC_id = 0; CC_id < RC.nb_mac_CC[module_idP]; CC_id++) {
    N_RB_DL[CC_id] = to_prb(cc[CC_id].mib->message.dl_Bandwidth);
    min_rb_unit[CC_id] = get_min_rb_unit(module_idP, CC_id);
    // get number of PRBs less those used by common channels
    total_nb_available_rb[CC_id] = N_RB_DL[CC_id];
    for (i = 0; i < N_RB_DL[CC_id]; i++)
      if (cc[CC_id].vrb_map[i] != 0)
        total_nb_available_rb[CC_id]--;

    N_RBG[CC_id] = to_rbg(cc[CC_id].mib->message.dl_Bandwidth);

    // store the global enb stats:
    eNB->eNB_stats[CC_id].num_dlactive_UEs = UE_list->num_UEs;
    eNB->eNB_stats[CC_id].available_prbs = total_nb_available_rb[CC_id];
    eNB->eNB_stats[CC_id].total_available_prbs += total_nb_available_rb[CC_id];
    eNB->eNB_stats[CC_id].dlsch_bytes_tx = 0;
    eNB->eNB_stats[CC_id].dlsch_pdus_tx = 0;
  }

  // CALLING Pre_Processor for downlink scheduling
  // (Returns estimation of RBs required by each UE and the allocation on sub-band)
  VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_DLSCH_PREPROCESSOR, VCD_FUNCTION_IN);

  start_meas(&eNB->schedule_dlsch_preprocessor);
  dlsch_scheduler_pre_processor(module_idP,
                                slice_idxP,
                                frameP,
                                subframeP,
                                mbsfn_flag,
                                eNB->slice_info.rballoc_sub);
  stop_meas(&eNB->schedule_dlsch_preprocessor);

  VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_DLSCH_PREPROCESSOR, VCD_FUNCTION_OUT);

  //RC.mac[module_idP]->slice_info.slice_counter--;
  // Do the multiplexing and actual allocation only when all slices have been pre-processed.
  //if (RC.mac[module_idP]->slice_info.slice_counter > 0) {
    //stop_meas(&eNB->schedule_dlsch);
    //VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_SCHEDULE_DLSCH, VCD_FUNCTION_OUT);
    //return;
  //}

  if (RC.mac[module_idP]->slice_info.interslice_share_active) {
    dlsch_scheduler_interslice_multiplexing(module_idP, frameP, subframeP, eNB->slice_info.rballoc_sub);
    /* the interslice multiplexing re-sorts the UE_list for the slices it tries
     * to multiplex, so we need to sort it for the current slice again */
    sort_UEs(module_idP, slice_idxP, frameP, subframeP);
  }

  for (CC_id = 0; CC_id < RC.nb_mac_CC[module_idP]; CC_id++) {
    LOG_D(MAC, "doing schedule_ue_spec for CC_id %d\n", CC_id);

    dl_req = &eNB->DL_req[CC_id].dl_config_request_body;

    if (mbsfn_flag[CC_id] > 0)
      continue;

    for (UE_id = UE_list->head; UE_id >= 0; UE_id = UE_list->next[UE_id]) {
      LOG_D(MAC, "doing schedule_ue_spec for CC_id %d UE %d\n", CC_id, UE_id);
      continue_flag = 0; // reset the flag to allow allocation for the remaining UEs
      rnti = UE_RNTI(module_idP, UE_id);
      eNB_UE_stats = &UE_list->eNB_UE_stats[CC_id][UE_id];
      ue_sched_ctl = &UE_list->UE_sched_ctrl[UE_id];

      if (rnti == NOT_A_RNTI) {
        LOG_D(MAC, "Cannot find rnti for UE_id %d (num_UEs %d)\n", UE_id, UE_list->num_UEs);
        continue_flag = 1;
      }

      if (eNB_UE_stats == NULL) {
        LOG_D(MAC, "[eNB] Cannot find eNB_UE_stats\n");
        continue_flag = 1;
      }

      if (!ue_dl_slice_membership(module_idP, UE_id, slice_idxP)) {
        LOG_D(MAC, "UE%d is not part of slice %d ID %d\n",
              UE_id, slice_idxP, RC.mac[module_idP]->slice_info.dl[slice_idxP].id);
        /* prevent execution of add_ue_dlsch_info(), it is done by the other
         * slice */
        continue;
      }

      if (continue_flag != 1) {
        switch (get_tmode(module_idP, CC_id, UE_id)) {
          case 1:
          case 2:
          case 7:
            aggregation = get_aggregation(get_bw_index(module_idP, CC_id),
                                          ue_sched_ctl->dl_cqi[CC_id],
                                          format1);
            break;
          case 3:
            aggregation = get_aggregation(get_bw_index(module_idP, CC_id),
                                          ue_sched_ctl->dl_cqi[CC_id],
                                          format2A);
            break;
          default:
            LOG_W(MAC, "Unsupported transmission mode %d\n", get_tmode(module_idP, CC_id, UE_id));
            aggregation = 2;
        }
      }

      /* if (continue_flag != 1 */
      if ((ue_sched_ctl->pre_nb_available_rbs[CC_id] == 0) ||	// no RBs allocated
	  CCE_allocation_infeasible(module_idP, CC_id, 1, subframeP,
				    aggregation, rnti)) {
	LOG_D(MAC,
	      "[eNB %d] Frame %d : no RB allocated for UE %d on CC_id %d: continue \n",
	      module_idP, frameP, UE_id, CC_id);
	continue_flag = 1;	//to next user (there might be rbs availiable for other UEs in TM5
      }

      // If TDD
      if (cc[CC_id].tdd_Config != NULL) {    //TDD
        set_ue_dai(subframeP,
                   UE_id,
                   CC_id,
                   cc[CC_id].tdd_Config->subframeAssignment,
                   UE_list);
        // update UL DAI after DLSCH scheduling
        set_ul_DAI(module_idP, UE_id, CC_id, frameP, subframeP);
      }

      if (continue_flag == 1) {
        add_ue_dlsch_info(module_idP, CC_id, UE_id, subframeP, S_DL_NONE);
        continue;
      }

      nb_available_rb = ue_sched_ctl->pre_nb_available_rbs[CC_id];
      harq_pid = frame_subframe2_dl_harq_pid(cc->tdd_Config,frameP ,subframeP);

      round = ue_sched_ctl->round[CC_id][harq_pid];

      UE_list->eNB_UE_stats[CC_id][UE_id].crnti = rnti;
      UE_list->eNB_UE_stats[CC_id][UE_id].rrc_status = mac_eNB_get_rrc_status(module_idP, rnti);
      UE_list->eNB_UE_stats[CC_id][UE_id].harq_pid = harq_pid;
      UE_list->eNB_UE_stats[CC_id][UE_id].harq_round = round;

      if (UE_list->eNB_UE_stats[CC_id][UE_id].rrc_status < RRC_CONNECTED) {
        LOG_D(MAC, "UE %d is not in RRC_CONNECTED\n", UE_id);
        continue;
      }

      header_length_total = 0;
      sdu_length_total = 0;
      num_sdus = 0;

      /*
      DevCheck(((eNB_UE_stats->dl_cqi < MIN_CQI_VALUE) ||
                (eNB_UE_stats->dl_cqi > MAX_CQI_VALUE)),
                eNB_UE_stats->dl_cqi, MIN_CQI_VALUE, MAX_CQI_VALUE);
      */
      if (nfapi_mode) {
        eNB_UE_stats->dlsch_mcs1 = 10; // cqi_to_mcs[ue_sched_ctl->dl_cqi[CC_id]];
      } else { // this operation is also done in the preprocessor
        eNB_UE_stats->dlsch_mcs1 = cmin(eNB_UE_stats->dlsch_mcs1,
                                        eNB->slice_info.dl[slice_idxP].maxmcs);  // cmin(eNB_UE_stats->dlsch_mcs1, openair_daq_vars.target_ue_dl_mcs);
      }

      // Store stats
      // UE_list->eNB_UE_stats[CC_id][UE_id].dl_cqi= eNB_UE_stats->dl_cqi;

      // Initializing the rb allocation indicator for each UE
      for (j = 0; j < N_RBG[CC_id]; j++) {
        UE_list->UE_template[CC_id][UE_id].rballoc_subband[harq_pid][j] = 0;
      }

      LOG_D(MAC,
            "[eNB %d] Frame %d: Scheduling UE %d on CC_id %d (rnti %x, harq_pid %d, round %d, rb %d, cqi %d, mcs %d, rrc %d)\n",
            module_idP, frameP, UE_id, CC_id, rnti, harq_pid, round,
            nb_available_rb, ue_sched_ctl->dl_cqi[CC_id],
            eNB_UE_stats->dlsch_mcs1,
            UE_list->eNB_UE_stats[CC_id][UE_id].rrc_status);

      /* process retransmission  */
      if (round != 8) {

        // get freq_allocation
        nb_rb = UE_list->UE_template[CC_id][UE_id].nb_rb[harq_pid];
        TBS = get_TBS_DL(UE_list->UE_template[CC_id][UE_id].oldmcs1[harq_pid], nb_rb);

	if (nb_rb <= nb_available_rb) {
	  if (cc[CC_id].tdd_Config != NULL) {
	    UE_list->UE_template[CC_id][UE_id].DAI++;
	    update_ul_dci(module_idP, CC_id, rnti,
			  UE_list->UE_template[CC_id][UE_id].DAI, subframeP);
	    LOG_D(MAC,
		  "DAI update: CC_id %d subframeP %d: UE %d, DAI %d\n",
		  CC_id, subframeP, UE_id,
		  UE_list->UE_template[CC_id][UE_id].DAI);
	  }

          if (nb_rb == ue_sched_ctl->pre_nb_available_rbs[CC_id]) {
            for (j = 0; j < N_RBG[CC_id]; ++j) { // for indicating the rballoc for each sub-band
              UE_list->UE_template[CC_id][UE_id].rballoc_subband[harq_pid][j] = ue_sched_ctl->rballoc_sub_UE[CC_id][j];
            }
          } else {
            nb_rb_temp = nb_rb;
            j = 0;

            while ((nb_rb_temp > 0) && (j < N_RBG[CC_id])) {
              if (ue_sched_ctl->rballoc_sub_UE[CC_id][j] == 1) {
                if (UE_list->UE_template[CC_id][UE_id].rballoc_subband[harq_pid][j])
                  printf("WARN: rballoc_subband not free for retrans?\n");
                UE_list->UE_template[CC_id][UE_id].rballoc_subband[harq_pid][j] = ue_sched_ctl->rballoc_sub_UE[CC_id][j];

                if ((j == N_RBG[CC_id] - 1) && ((N_RB_DL[CC_id] == 25) || (N_RB_DL[CC_id] == 50))) {
                  nb_rb_temp = nb_rb_temp - min_rb_unit[CC_id] + 1;
                } else {
                  nb_rb_temp = nb_rb_temp - min_rb_unit[CC_id];
                }
              }

              j = j + 1;
            }
          }

          nb_available_rb -= nb_rb;
          /*
          eNB->mu_mimo_mode[UE_id].pre_nb_available_rbs = nb_rb;
          eNB->mu_mimo_mode[UE_id].dl_pow_off = ue_sched_ctl->dl_pow_off[CC_id];

          for(j = 0; j < N_RBG[CC_id]; ++j) {
            eNB->mu_mimo_mode[UE_id].rballoc_sub[j] = UE_list->UE_template[CC_id][UE_id].rballoc_subband[harq_pid][j];
          }
          */

          switch (get_tmode(module_idP, CC_id, UE_id)) {
            case 1:
            case 2:
            case 7:
            default:
              LOG_D(MAC, "retransmission DL_REQ: rnti:%x\n", rnti);

              dl_config_pdu = &dl_req->dl_config_pdu_list[dl_req->number_pdu];
              memset((void *) dl_config_pdu, 0, sizeof(nfapi_dl_config_request_pdu_t));
              dl_config_pdu->pdu_type = NFAPI_DL_CONFIG_DCI_DL_PDU_TYPE;
              dl_config_pdu->pdu_size = (uint8_t) (2 + sizeof(nfapi_dl_config_dci_dl_pdu));
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.tl.tag = NFAPI_DL_CONFIG_REQUEST_DCI_DL_PDU_REL8_TAG;
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.dci_format = NFAPI_DL_DCI_FORMAT_1;
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.aggregation_level =
                      get_aggregation(get_bw_index(module_idP, CC_id),
                                      ue_sched_ctl->dl_cqi[CC_id],
                                      format1);
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.rnti = rnti;
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.rnti_type = 1; // CRNTI: see Table 4-10 from SCF082 - nFAPI specifications
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.transmission_power = 6000; // equal to RS power

              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.harq_process = harq_pid;
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.tpc = 1; // Don't adjust power when retransmitting
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.new_data_indicator_1 = UE_list->UE_template[CC_id][UE_id].oldNDI[harq_pid];
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.mcs_1 = UE_list->UE_template[CC_id][UE_id].oldmcs1[harq_pid];
              dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.redundancy_version_1 = round & 3;

              // TDD
              if (cc[CC_id].tdd_Config != NULL) {
                dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.downlink_assignment_index =
                        (UE_list->UE_template[CC_id][UE_id].DAI - 1) & 3;
                LOG_D(MAC,
                      "[eNB %d] Retransmission CC_id %d : harq_pid %d, round %d, dai %d, mcs %d\n",
                      module_idP, CC_id, harq_pid, round,
                      (UE_list->UE_template[CC_id][UE_id].DAI - 1),
                      UE_list->UE_template[CC_id][UE_id].oldmcs1[harq_pid]);
              } else {
                LOG_D(MAC,
                      "[eNB %d] Retransmission CC_id %d : harq_pid %d, round %d, mcs %d\n",
                      module_idP, CC_id, harq_pid, round,
                      UE_list->UE_template[CC_id][UE_id].oldmcs1[harq_pid]);

	    }
	    if (!CCE_allocation_infeasible(module_idP, CC_id, 1, subframeP,
					   dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.aggregation_level, rnti)) {
	      dl_req->number_dci++;
	      dl_req->number_pdu++;
	      dl_req->tl.tag = NFAPI_DL_CONFIG_REQUEST_BODY_TAG;

	      eNB->DL_req[CC_id].sfn_sf = frameP<<4 | subframeP;
	      eNB->DL_req[CC_id].header.message_id = NFAPI_DL_CONFIG_REQUEST;

                fill_nfapi_dlsch_config(eNB, dl_req, TBS, -1,
                                        /* retransmission, no pdu_index */
                                        rnti, 0, // type 0 allocation from 7.1.6 in 36.213
                                        0,    // virtual_resource_block_assignment_flag, unused here
                                        0,    // resource_block_coding, to be filled in later
                                        getQm(UE_list->UE_template[CC_id][UE_id].oldmcs1[harq_pid]),
                                        round & 3, // redundancy version
                                        1,    // transport blocks
                                        0,    // transport block to codeword swap flag
                                        cc[CC_id].p_eNB == 1 ? 0 : 1,    // transmission_scheme
                                        1,    // number of layers
                                        1,    // number of subbands
                        //                      uint8_t codebook_index,
                                        4,    // UE category capacity
                                        UE_list->UE_template[CC_id][UE_id].physicalConfigDedicated->pdsch_ConfigDedicated->p_a,
                                        0,    // delta_power_offset for TM5
                                        0,    // ngap
                                        0,    // nprb
                                        cc[CC_id].p_eNB == 1 ? 1 : 2,    // transmission mode
                                        0,    //number of PRBs treated as one subband, not used here
                                        0    // number of beamforming vectors, not used here
                );

                LOG_D(MAC,
                      "Filled NFAPI configuration for DCI/DLSCH %d, retransmission round %d\n",
                      eNB->pdu_index[CC_id], round);

                program_dlsch_acknak(module_idP, CC_id, UE_id, frameP, subframeP,
                                     dl_config_pdu->dci_dl_pdu.dci_dl_pdu_rel8.cce_idx);
                // No TX request for retransmission (check if null request for FAPI)
              } else {
                LOG_W(MAC,
                      "Frame %d, Subframe %d: Dropping DLSCH allocation for UE %d\%x, infeasible CCE allocation\n",
                      frameP, subframeP, UE_id, rnti);
              }
          }

          add_ue_dlsch_info(module_idP, CC_id, UE_id, subframeP, S_DL_SCHEDULED);

	  //eNB_UE_stats->dlsch_trials[round]++;
	  UE_list->eNB_UE_stats[CC_id][UE_id].num_retransmission += 1;
	  UE_list->eNB_UE_stats[CC_id][UE_id].rbs_used_retx = nb_rb;
	  UE_list->eNB_UE_stats[CC_id][UE_id].total_rbs_used_retx += nb_rb;
	  UE_list->eNB_UE_stats[CC_id][UE_id].dlsch_mcs1 = eNB_UE_stats->dlsch_mcs1;
	  UE_list->eNB_UE_stats[CC_id][UE_id].dlsch_mcs2 = eNB_UE_stats->dlsch_mcs1;
	} else {
	  LOG_D(MAC,
		"[eNB %d] Frame %d CC_id %d : don't schedule UE %d, its retransmission takes more resources than we have\n",
		module_idP, frameP, CC_id, UE_id);
	}
      } else {		/* This is a potentially new SDU opportunity */
	rlc_status.bytes_in_buffer = 0;

	// Now check RLC information to compute number of required RBs
	// get maximum TBS size for RLC request
	TBS = get_TBS_DL(eNB_UE_stats->dlsch_mcs1, nb_available_rb);

	// add the length for  all the control elements (timing adv, drx, etc) : header + payload

        if (ue_sched_ctl->ta_timer == 0) {
          ta_update = ue_sched_ctl->ta_update;
          /* if we send TA then set timer to not send it for a while */
          if (ta_update != 31)
            ue_sched_ctl->ta_timer = 20;
          /* reset ta_update */
          ue_sched_ctl->ta_update = 31;
        } else {
          ta_update = 31;
        }

        ta_len = (ta_update != 31) ? 2 : 0;

	// RLC data on DCCH
	if (TBS - ta_len - header_length_total - sdu_length_total - 3 > 0) {
	  rlc_status = mac_rlc_status_ind(module_idP, rnti, module_idP, frameP, subframeP, ENB_FLAG_YES, MBMS_FLAG_NO, DCCH,
                                          TBS - ta_len - header_length_total - sdu_length_total - 3
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
                                                    ,0, 0
#endif
                          );

          sdu_lengths[0] = 0;

	  if (rlc_status.bytes_in_buffer > 0) {
	    LOG_D(MAC, "[eNB %d] SFN/SF %d.%d, DL-DCCH->DLSCH CC_id %d, Requesting %d bytes from RLC (RRC message)\n",
		  module_idP, frameP, subframeP, CC_id,
		  TBS - ta_len - header_length_total - sdu_length_total - 3);

	    sdu_lengths[0] = mac_rlc_data_req(module_idP, rnti, module_idP, frameP, ENB_FLAG_YES, MBMS_FLAG_NO, DCCH,
                                              TBS, //not used
					      (char *)&dlsch_buffer[0]
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
                          ,0, 0
#endif
                          );

            pthread_mutex_lock(&rrc_release_freelist);
            if((rrc_release_info.num_UEs > 0) && (rlc_am_mui.rrc_mui_num > 0)){
              uint16_t release_total = 0;
              for(uint16_t release_num = 0;release_num < NUMBER_OF_UE_MAX;release_num++){
                if(rrc_release_info.RRC_release_ctrl[release_num].flag > 0){
                  release_total++;
                }else{
                  continue;
                }

                if(rrc_release_info.RRC_release_ctrl[release_num].flag == 1){
                  if(rrc_release_info.RRC_release_ctrl[release_num].rnti == rnti){
                    for(uint16_t mui_num = 0;mui_num < rlc_am_mui.rrc_mui_num;mui_num++){
                      if(rrc_release_info.RRC_release_ctrl[release_num].rrc_eNB_mui == rlc_am_mui.rrc_mui[mui_num]){
                        rrc_release_info.RRC_release_ctrl[release_num].flag = 3;
                        LOG_D(MAC,"DLSCH Release send:index %d rnti %x mui %d mui_num %d flag 1->3\n",release_num,rnti,rlc_am_mui.rrc_mui[mui_num],mui_num);
                        break;
                      }
                    }
                  }
                }
                if(rrc_release_info.RRC_release_ctrl[release_num].flag == 2){
                  if(rrc_release_info.RRC_release_ctrl[release_num].rnti == rnti){
                    for(uint16_t mui_num = 0;mui_num < rlc_am_mui.rrc_mui_num;mui_num++){
                      if(rrc_release_info.RRC_release_ctrl[release_num].rrc_eNB_mui == rlc_am_mui.rrc_mui[mui_num]){
                        rrc_release_info.RRC_release_ctrl[release_num].flag = 4;
                        LOG_D(MAC,"DLSCH Release send:index %d rnti %x mui %d mui_num %d flag 2->4\n",release_num,rnti,rlc_am_mui.rrc_mui[mui_num],mui_num);
                        break;
                      }
                    }
                  }
                }
                if(release_total >= rrc_release_info.num_UEs)
                  break;
              }
            }
            pthread_mutex_unlock(&rrc_release_freelist);

            RA_t *ra = &eNB->common_channels[CC_id].ra[0];
            for (uint8_t ra_ii = 0; ra_ii < NB_RA_PROC_MAX; ra_ii++) {
              if((ra[ra_ii].rnti == rnti) && (ra[ra_ii].state == MSGCRNTI)){
                for(uint16_t mui_num = 0;mui_num < rlc_am_mui.rrc_mui_num;mui_num++){
                  if(ra[ra_ii].crnti_rrc_mui == rlc_am_mui.rrc_mui[mui_num]){
                    ra[ra_ii].crnti_harq_pid = harq_pid;
                    ra[ra_ii].state = MSGCRNTI_ACK;
                    break;
                  }
                }
              }
            }

            T(T_ENB_MAC_UE_DL_SDU, T_INT(module_idP),
              T_INT(CC_id), T_INT(rnti), T_INT(frameP),
              T_INT(subframeP), T_INT(harq_pid), T_INT(DCCH),
              T_INT(sdu_lengths[0]));

	    LOG_D(MAC, "[eNB %d][DCCH] CC_id %d Got %d bytes from RLC\n",
		  module_idP, CC_id, sdu_lengths[0]);

	    sdu_length_total = sdu_lengths[0];
	    sdu_lcids[0] = DCCH;
            UE_list->eNB_UE_stats[CC_id][UE_id].lcid_sdu[0] = DCCH;
            UE_list->eNB_UE_stats[CC_id][UE_id].sdu_length_tx[DCCH] = sdu_lengths[0];
	    UE_list->eNB_UE_stats[CC_id][UE_id].num_pdu_tx[DCCH] += 1;
	    UE_list->eNB_UE_stats[CC_id][UE_id].num_bytes_tx[DCCH] += sdu_lengths[0];

            header_length_last = 1 + 1 + (sdu_lengths[0] >= 128);
            header_length_total += header_length_last;

	    num_sdus = 1;

#ifdef DEBUG_eNB_SCHEDULER
            LOG_T(MAC,
              "[eNB %d][DCCH] CC_id %d Got %d bytes :",
              module_idP, CC_id, sdu_lengths[0]);

            for (j = 0; j < sdu_lengths[0]; ++j) {
              LOG_T(MAC, "%x ", dlsch_buffer[j]);
            }

            LOG_T(MAC, "\n");
#endif
	  }
	}

	// RLC data on DCCH1
	if (TBS - ta_len - header_length_total - sdu_length_total - 3 > 0) {
	  rlc_status = mac_rlc_status_ind(module_idP, rnti, module_idP, frameP, subframeP, ENB_FLAG_YES, MBMS_FLAG_NO, DCCH + 1,
                                          TBS - ta_len - header_length_total - sdu_length_total - 3
#if (RRC_VERSION >= MAKE_VERSION(14, 0, 0))
                                                    ,0, 0
#endif
                                         );

	  // DCCH SDU
	  sdu_lengths[num_sdus] = 0;

	  if (rlc_status.bytes_in_buffer > 0) {
	    LOG_D(MAC, "[eNB %d], Frame %d, DCCH1->DLSCH, CC_id %d, Requesting %d bytes from RLC (RRC message)\n",
		  module_idP, frameP, CC_id,
		  TBS - ta_len - header_length_total - sdu_length_total - 3);

	    sdu_lengths[num_sdus] += mac_rlc_data_req(module_idP, rnti, module_idP, frameP, ENB_FLAG_YES, MBMS_FLAG_NO, DCCH + 1,
                                                      TBS, //not used