eNB_scheduler.c

/*******************************************************************************

  Eurecom OpenAirInterface
  Copyright(c) 1999 - 2010 Eurecom

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  more details.

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  this program; if not, write to the Free Software Foundation, Inc.,
  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Contact Information
  Openair Admin: openair_admin@eurecom.fr
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 *******************************************************************************/
/*! \file eNB_scheduler.c
 * \brief procedures related to UE
 * \author Raymond Knopp, Navid Nikaein
 * \date 2011
 * \email: navid.nikaein@eurecom.fr
 * \version 0.5
 * @ingroup _mac

 */

#include "assertions.h"
#include "PHY/defs.h"
#include "PHY/extern.h"

#include "SCHED/defs.h"
#include "SCHED/extern.h"

#include "LAYER2/MAC/defs.h"
#include "LAYER2/MAC/extern.h"
#include "UTIL/LOG/log.h"
#include "UTIL/LOG/vcd_signal_dumper.h"
#include "UTIL/OPT/opt.h"
#include "OCG.h"
#include "OCG_extern.h"
#include "ARCH/CBMIMO1/DEVICE_DRIVER/extern.h"
#include "ARCH/CBMIMO1/DEVICE_DRIVER/defs.h"
#include "ARCH/CBMIMO1/DEVICE_DRIVER/from_grlib_softregs.h"

#include "RRC/LITE/extern.h"
#include "RRC/L2_INTERFACE/openair_rrc_L2_interface.h"

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

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

#define ENABLE_MAC_PAYLOAD_DEBUG
#define DEBUG_eNB_SCHEDULER 1
//#define DEBUG_HEADER_PARSING 1
//#define DEBUG_PACKET_TRACE 1

/*
  #ifndef USER_MODE
  #define msg debug_msg
  #endif
 */

extern inline unsigned int taus(void);


void init_ue_sched_info(void){
  module_id_t i,j;
  for (i=0;i<NUMBER_OF_eNB_MAX;i++){
      for (j=0;j<NUMBER_OF_UE_MAX;j++){
          // init DL
          eNB_dlsch_info[i][j].weight           = 0;
          eNB_dlsch_info[i][j].subframe         = 0;
          eNB_dlsch_info[i][j].serving_num      = 0;
          eNB_dlsch_info[i][j].status           = S_DL_NONE;
          // init UL
          eNB_ulsch_info[i][j].subframe         = 0;
          eNB_ulsch_info[i][j].serving_num      = 0;
          eNB_ulsch_info[i][j].status           = S_UL_NONE;
      }
  }
}

void add_ue_ulsch_info(module_id_t module_idP, module_id_t ue_mod_idP, sub_frame_t subframeP, UE_ULSCH_STATUS status){

  eNB_ulsch_info[module_idP][ue_mod_idP].rnti             = find_UE_RNTI(module_idP,ue_mod_idP);
  eNB_ulsch_info[module_idP][ue_mod_idP].subframe         = subframeP;
  eNB_ulsch_info[module_idP][ue_mod_idP].status           = status;

  eNB_ulsch_info[module_idP][ue_mod_idP].serving_num++;

}
void add_ue_dlsch_info(module_id_t module_idP, module_id_t ue_mod_idP, sub_frame_t subframeP, UE_DLSCH_STATUS status){

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

  eNB_dlsch_info[module_idP][ue_mod_idP].serving_num++;

}

unsigned char get_ue_weight(module_id_t module_idP, module_id_t ue_mod_idP){

  return(eNB_dlsch_info[module_idP][ue_mod_idP].weight);

}

// return is rnti ???
module_id_t schedule_next_ulue(module_id_t module_idP, module_id_t ue_mod_idP, sub_frame_t subframeP){

  module_id_t next_ue;

  // first phase: scheduling for ACK
  switch (subframeP) {
  // scheduling for subframeP 2: for scheduled user during subframeP 5 and 6
  case 8:
    if  ((eNB_dlsch_info[module_idP][ue_mod_idP].status == S_DL_SCHEDULED) &&
        (eNB_dlsch_info[module_idP][ue_mod_idP].subframe == 5 || eNB_dlsch_info[module_idP][ue_mod_idP].subframe == 6)){
        // set the downlink status
        eNB_dlsch_info[module_idP][ue_mod_idP].status = S_DL_BUFFERED;
        return ue_mod_idP;
    }
    break;
    // scheduling for subframeP 3: for scheduled user during subframeP 7 and 8
  case 9:
    if  ((eNB_dlsch_info[module_idP][ue_mod_idP].status == S_DL_SCHEDULED) &&
        (eNB_dlsch_info[module_idP][ue_mod_idP].subframe == 7 || eNB_dlsch_info[module_idP][ue_mod_idP].subframe == 8)){
        eNB_dlsch_info[module_idP][ue_mod_idP].status = S_DL_BUFFERED;
        return ue_mod_idP;
    }
    break;
    // scheduling UL subframeP 4: for scheduled user during subframeP 9 and 0
  case 0 :
    if  ((eNB_dlsch_info[module_idP][ue_mod_idP].status == S_DL_SCHEDULED) &&
        (eNB_dlsch_info[module_idP][ue_mod_idP].subframe == 9 || eNB_dlsch_info[module_idP][ue_mod_idP].subframe == 0)){
        eNB_dlsch_info[module_idP][ue_mod_idP].status = S_DL_BUFFERED;
        return ue_mod_idP;
    }
    break;
  default:
    break;
  }

  // second phase
  for (next_ue=0; next_ue <NUMBER_OF_UE_MAX; next_ue++ ){

      if  (eNB_ulsch_info[module_idP][next_ue].status == S_UL_WAITING )
        return next_ue;
      else if (eNB_ulsch_info[module_idP][next_ue].status == S_UL_SCHEDULED){
          eNB_ulsch_info[module_idP][next_ue].status = S_UL_BUFFERED;
      }
  }
  for (next_ue=0; next_ue <NUMBER_OF_UE_MAX; next_ue++ ){
      if (eNB_ulsch_info[module_idP][next_ue].status != S_UL_NONE )// do this just for active UEs
        eNB_ulsch_info[module_idP][next_ue].status = S_UL_WAITING;
  }
  next_ue = 0;
  return next_ue;

}

module_id_t schedule_next_dlue(module_id_t module_idP, sub_frame_t subframeP){

  module_id_t next_ue;

  for (next_ue=0; next_ue < NUMBER_OF_UE_MAX; next_ue++ ){
      if  (eNB_dlsch_info[module_idP][next_ue].status == S_DL_WAITING)
        return next_ue;
  }
  for (next_ue=0; next_ue <NUMBER_OF_UE_MAX; next_ue++ )
    if  (eNB_dlsch_info[module_idP][next_ue].status == S_DL_BUFFERED) {
        eNB_dlsch_info[module_idP][next_ue].status = S_DL_WAITING;
    }
  // next_ue = -1;
  return (module_id_t)(-1);//next_ue;

}

void initiate_ra_proc(module_id_t module_idP, frame_t frameP, uint16_t preamble_index,int16_t timing_offset,uint8_t sect_id,sub_frame_t subframeP,uint8_t f_id) {

  uint8_t i;

  LOG_I(MAC,"[eNB %d][RAPROC] Frame %d Initiating RA procedure for preamble index %d\n",module_idP,frameP,preamble_index);

  for (i=0;i<NB_RA_PROC_MAX;i++) {
      if (eNB_mac_inst[module_idP].RA_template[i].RA_active==FALSE) {
          eNB_mac_inst[module_idP].RA_template[i].RA_active=TRUE;
          eNB_mac_inst[module_idP].RA_template[i].generate_rar=1;
          eNB_mac_inst[module_idP].RA_template[i].generate_Msg4=0;
          eNB_mac_inst[module_idP].RA_template[i].wait_ack_Msg4=0;
          eNB_mac_inst[module_idP].RA_template[i].timing_offset=timing_offset;
          // Put in random rnti (to be replaced with proper procedure!!)
          eNB_mac_inst[module_idP].RA_template[i].rnti = taus();
          eNB_mac_inst[module_idP].RA_template[i].RA_rnti = 1+subframeP+(10*f_id);
          eNB_mac_inst[module_idP].RA_template[i].preamble_index = preamble_index;
          LOG_D(MAC,"[eNB %d][RAPROC] Frame %d Activating RAR generation for process %d, rnti %x, RA_active %d\n",
              module_idP,frameP,i,eNB_mac_inst[module_idP].RA_template[i].rnti,
              eNB_mac_inst[module_idP].RA_template[i].RA_active);

          return;
      }
  }
}

void cancel_ra_proc(module_id_t module_idP, frame_t frameP, rnti_t rnti) {
  unsigned char i;
  LOG_I(MAC,"[eNB %d][RAPROC] Frame %d Cancelling RA procedure for UE rnti %x\n",module_idP,frameP,rnti);

  for (i=0;i<NB_RA_PROC_MAX;i++) {
      if (rnti == eNB_mac_inst[module_idP].RA_template[i].rnti) {
          eNB_mac_inst[module_idP].RA_template[i].RA_active=FALSE;
          eNB_mac_inst[module_idP].RA_template[i].generate_rar=0;
          eNB_mac_inst[module_idP].RA_template[i].generate_Msg4=0;
          eNB_mac_inst[module_idP].RA_template[i].wait_ack_Msg4=0;
          eNB_mac_inst[module_idP].RA_template[i].timing_offset=0;
          eNB_mac_inst[module_idP].RA_template[i].RRC_timer=20;
          eNB_mac_inst[module_idP].RA_template[i].rnti = 0;
      }
  }
}

void terminate_ra_proc(module_id_t module_idP,frame_t frameP,rnti_t rnti,unsigned char *msg3, uint16_t msg3_len) {

  unsigned char rx_ces[MAX_NUM_CE],num_ce,num_sdu,i,*payload_ptr;
  unsigned char rx_lcids[NB_RB_MAX];
  uint16_t rx_lengths[NB_RB_MAX];
  int8_t UE_id;

  LOG_I(MAC,"[eNB %d][RAPROC] Frame %d, Received msg3 %x.%x.%x.%x.%x.%x, Terminating RA procedure for UE rnti %x\n",
      module_idP,frameP,
      msg3[3],msg3[4],msg3[5],msg3[6],msg3[7], msg3[8], rnti);

  for (i=0;i<NB_RA_PROC_MAX;i++) {
      LOG_D(MAC,"[RAPROC] Checking proc %d : rnti (%x, %x), active %d\n",i,
          eNB_mac_inst[module_idP].RA_template[i].rnti, rnti,
          eNB_mac_inst[module_idP].RA_template[i].RA_active);
      if ((eNB_mac_inst[module_idP].RA_template[i].rnti==rnti) &&
          (eNB_mac_inst[module_idP].RA_template[i].RA_active==TRUE)) {

          payload_ptr = parse_ulsch_header(msg3,&num_ce,&num_sdu,rx_ces,rx_lcids,rx_lengths,msg3_len);
          LOG_D(MAC,"[eNB %d][RAPROC] Frame %d Received CCCH: length %d, offset %d\n",
              module_idP,frameP,rx_lengths[0],payload_ptr-msg3);
          if (/*(num_ce == 0) &&*/ (num_sdu==1) && (rx_lcids[0] == CCCH)) { // This is an RRCConnectionRequest/Restablishment
              memcpy(&eNB_mac_inst[module_idP].RA_template[i].cont_res_id[0],payload_ptr,6);
              LOG_D(MAC,"[eNB %d][RAPROC] Frame %d Received CCCH: length %d, offset %d\n",
                  module_idP,frameP,rx_lengths[0],payload_ptr-msg3);
              UE_id=add_new_ue(module_idP,eNB_mac_inst[module_idP].RA_template[i].rnti);
              if (UE_id==-1) {
                  mac_xface->macphy_exit("[MAC][eNB] Max user count reached\n");
              }
              else {
                  LOG_I(MAC,"[eNB %d][RAPROC] Frame %d Added user with rnti %x => UE %d\n",
                      module_idP,frameP,eNB_mac_inst[module_idP].RA_template[i].rnti,UE_id);
              }

              if (Is_rrc_registered == 1)
                mac_rrc_data_ind(module_idP,frameP,CCCH,(uint8_t *)payload_ptr,rx_lengths[0],1,module_idP,0);
              // add_user.  This is needed to have the rnti for configuring UE (PHY). The UE is removed if RRC
              // doesn't provide a CCCH SDU

          }
          else if (num_ce >0) {  // handle msg3 which is not RRCConnectionRequest
              //	process_ra_message(msg3,num_ce,rx_lcids,rx_ces);
          }

          eNB_mac_inst[module_idP].RA_template[i].generate_Msg4 = 1;
          eNB_mac_inst[module_idP].RA_template[i].wait_ack_Msg4 = 0;

          return;
      } // if process is active

  } // loop on RA processes
}

DCI_PDU *get_dci_sdu(module_id_t module_idP, frame_t frameP, sub_frame_t subframeP) {

  return(&eNB_mac_inst[module_idP].DCI_pdu);

}

module_id_t find_UE_id(module_id_t module_idP, rnti_t rnti) {

  module_id_t ue_mod_id;

  for (ue_mod_id=0;ue_mod_id<NUMBER_OF_UE_MAX;ue_mod_id++) {
    //   if (mac_get_rrc_status(module_idP,1,ue_mod_id) >= RRC_CONNECTED) {
      if (eNB_mac_inst[module_idP].UE_template[ue_mod_id].rnti==rnti) {
	return(ue_mod_id);
      }
  }
  return(module_id_t)(-1);

}

rnti_t find_UE_RNTI(module_id_t module_idP, module_id_t ue_mod_idP) {

  return (eNB_mac_inst[module_idP].UE_template[ue_mod_idP].rnti);

}
boolean_t is_UE_active(module_id_t module_idP, module_id_t ue_mod_idP ){
  if (eNB_mac_inst[module_idP].UE_template[ue_mod_idP].rnti !=0 )
    return TRUE;
  else
    return FALSE ;
}
uint8_t find_active_UEs(module_id_t module_idP){

  module_id_t        ue_mod_id      = 0;
  rnti_t        rnti         = 0;
  uint8_t            nb_active_ue = 0;

  for (ue_mod_id=0;ue_mod_id<NUMBER_OF_UE_MAX;ue_mod_id++) {

      if (((rnti=eNB_mac_inst[module_idP].UE_template[ue_mod_id].rnti) !=0)&&(eNB_mac_inst[module_idP].UE_template[ue_mod_id].ul_active==TRUE)){

          if (mac_xface->get_eNB_UE_stats(module_idP,rnti) != NULL){ // check at the phy enb_ue state for this rnti
              nb_active_ue++;
          }
          else { // this ue is removed at the phy => remove it at the mac as well
              mac_remove_ue(module_idP, ue_mod_id);
          }
      }
  }
  return(nb_active_ue);
}

// function for determining which active ue should be granted resources in uplink based on BSR+QoS
uint8_t find_ulgranted_UEs(module_id_t module_idP){

  // all active users should be granted
  return(find_active_UEs(module_idP));
}

// function for determining which active ue should be granted resources in downlink based on CQI, SI, and BSR
uint8_t find_dlgranted_UEs(module_id_t module_idP){

  // all active users should be granted
  return(find_active_UEs(module_idP));
}
// get aggregatiob form phy for a give UE
unsigned char process_ue_cqi (module_id_t module_idP, module_id_t ue_mod_idP) {
  unsigned char aggregation=2;
  // check the MCS and SNR and set the aggregation accordingly
  return aggregation;
}
#ifdef CBA
uint8_t find_num_active_UEs_in_cbagroup(module_id_t module_idP, unsigned char group_id){

  module_id_t    UE_id;
  rnti_t    rnti;
  unsigned char nb_ue_in_pusch=0;
  LTE_eNB_UE_stats* eNB_UE_stats;

  for (UE_id=group_id;UE_id<NUMBER_OF_UE_MAX;UE_id+=eNB_mac_inst[module_idP].num_active_cba_groups) {

      if (((rnti=eNB_mac_inst[module_idP].UE_template[UE_id].rnti) !=0) &&
          (eNB_mac_inst[module_idP].UE_template[UE_id].ul_active==TRUE)    &&
          (mac_get_rrc_status(module_idP,1,UE_id) > RRC_CONNECTED)){
          //  && (UE_is_to_be_scheduled(module_idP,UE_id)))
          // check at the phy enb_ue state for this rnti
          if ((eNB_UE_stats= mac_xface->get_eNB_UE_stats(module_idP,rnti)) != NULL){
              if ((eNB_UE_stats->mode == PUSCH) && (UE_is_to_be_scheduled(module_idP,UE_id) == 0)){
                  nb_ue_in_pusch++;
              }
          }
      }
  }
  return(nb_ue_in_pusch);
}
#endif
int8_t add_new_ue(module_id_t enb_mod_idP, rnti_t rntiP) {
  module_id_t ue_mod_id;
  int         j;

  for (ue_mod_id=0;ue_mod_id<NUMBER_OF_UE_MAX;ue_mod_id++) {
      if (eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].rnti == 0) {
          eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].rnti = rntiP;
          for (j=0;j<8;j++) {
              eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].oldNDI[j]    = 0;
              eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].oldNDI_UL[j] = 0;
          }
          eNB_ulsch_info[enb_mod_idP][ue_mod_id].status = S_UL_WAITING;
          eNB_dlsch_info[enb_mod_idP][ue_mod_id].status = S_UL_WAITING;
          LOG_D(MAC,"[eNB] Add UE_id %d : rnti %x\n",ue_mod_id,eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].rnti);
          return((int8_t)ue_mod_id);
      }
  }
  return(-1);
}

int8_t mac_remove_ue(module_id_t enb_mod_idP, module_id_t ue_mod_idP) {

  LOG_I(MAC,"Removing UE %d (rnti %x)\n",ue_mod_idP,eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].rnti);

  // clear all remaining pending transmissions
  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].bsr_info[LCGID0]  = 0;
  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].bsr_info[LCGID1]  = 0;
  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].bsr_info[LCGID2]  = 0;
  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].bsr_info[LCGID3]  = 0;

  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].ul_SR             = 0;
  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].rnti              = 0;
  eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_idP].ul_active         = FALSE;
  eNB_ulsch_info[enb_mod_idP][ue_mod_idP].rnti                        = 0;
  eNB_ulsch_info[enb_mod_idP][ue_mod_idP].status                      = S_UL_NONE;
  eNB_dlsch_info[enb_mod_idP][ue_mod_idP].rnti                        = 0;
  eNB_dlsch_info[enb_mod_idP][ue_mod_idP].status                      = S_DL_NONE;

  rrc_eNB_free_UE_index(enb_mod_idP,ue_mod_idP);

  return(1);
}

unsigned char *get_dlsch_sdu(module_id_t module_idP, frame_t frameP, rnti_t rntiP, uint8_t TBindex) {

  module_id_t ue_mod_id;

  if (rntiP==SI_RNTI) {
      LOG_D(MAC,"[eNB %d] Frame %d Get DLSCH sdu for BCCH \n",module_idP,frameP);

      return((unsigned char *)&eNB_mac_inst[module_idP].BCCH_pdu.payload[0]);
  }
  else if ((ue_mod_id = find_UE_id(module_idP,rntiP)) != UE_INDEX_INVALID ){
    LOG_D(MAC,"[eNB %d] Frame %d:  Get DLSCH sdu for rnti %x => UE_id %d\n",module_idP,frameP,rntiP,ue_mod_id);
    return((unsigned char *)&eNB_mac_inst[module_idP].DLSCH_pdu[ue_mod_id][TBindex].payload[0]);
  } else {
    LOG_E(MAC,"[eNB %d] Frame %d: UE with RNTI %x does not exist\n", module_idP,frameP,rntiP);
    return NULL;
  }

}

unsigned char *parse_ulsch_header(unsigned char *mac_header,
    unsigned char *num_ce,
    unsigned char *num_sdu,
    unsigned char *rx_ces,
    unsigned char *rx_lcids,
    unsigned short *rx_lengths,
    unsigned short tb_length) {

  unsigned char not_done=1,num_ces=0,num_sdus=0,lcid,num_sdu_cnt;
  unsigned char *mac_header_ptr = mac_header;
  unsigned short length, ce_len=0;

  while (not_done==1) {

      if (((SCH_SUBHEADER_FIXED *)mac_header_ptr)->E == 0)
        not_done = 0;

      lcid = ((SCH_SUBHEADER_FIXED *)mac_header_ptr)->LCID;
      if (lcid < EXTENDED_POWER_HEADROOM) {
          if (not_done==0) { // last MAC SDU, length is implicit
              mac_header_ptr++;
              length = tb_length-(mac_header_ptr-mac_header)-ce_len;
              for (num_sdu_cnt=0; num_sdu_cnt < num_sdus ; num_sdu_cnt++)
                length -= rx_lengths[num_sdu_cnt];
          }
          else {
              if (((SCH_SUBHEADER_SHORT *)mac_header_ptr)->F == 0) {
                  length = ((SCH_SUBHEADER_SHORT *)mac_header_ptr)->L;
                  mac_header_ptr += 2;//sizeof(SCH_SUBHEADER_SHORT);
              }
              else { // F = 1
                  length = ((((SCH_SUBHEADER_LONG *)mac_header_ptr)->L_MSB & 0x7f ) << 8 ) | (((SCH_SUBHEADER_LONG *)mac_header_ptr)->L_LSB & 0xff);
                  mac_header_ptr += 3;//sizeof(SCH_SUBHEADER_LONG);
              }
          }
          LOG_D(MAC,"[eNB] sdu %d lcid %d tb_length %d length %d (offset now %d)\n",
              num_sdus,lcid,tb_length, length,mac_header_ptr-mac_header);
          rx_lcids[num_sdus] = lcid;
          rx_lengths[num_sdus] = length;
          num_sdus++;
      }
      else {  // This is a control element subheader POWER_HEADROOM, BSR and CRNTI
          if (lcid == SHORT_PADDING) {
              mac_header_ptr++;
          }
          else {
              rx_ces[num_ces] = lcid;
              num_ces++;
              mac_header_ptr++;
              if (lcid==LONG_BSR)
                ce_len+=3;
              else if (lcid==CRNTI)
                ce_len+=2;
              else if ((lcid==POWER_HEADROOM) || (lcid==TRUNCATED_BSR)|| (lcid== SHORT_BSR))
                ce_len++;
	      else {
		LOG_E(MAC,"unknown CE %d \n", lcid);
		exit(-1);
	      }
          }
      }
  }
  *num_ce = num_ces;
  *num_sdu = num_sdus;

  return(mac_header_ptr);
}

void SR_indication(module_id_t enb_mod_idP, frame_t frameP, rnti_t rntiP, sub_frame_t subframeP) {

  module_id_t ue_mod_id = find_UE_id(enb_mod_idP, rntiP);
  
  if (ue_mod_id  != UE_INDEX_INVALID ) {
      LOG_D(MAC,"[eNB %d][SR %x] Frame %d subframeP %d Signaling SR for UE %d \n",enb_mod_idP,rntiP,frameP,subframeP, ue_mod_id);
      eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].ul_SR = 1;
      eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].ul_active = TRUE;
  } else {
    //     AssertFatal(0, "find_UE_id(%u,rnti %d) not found", enb_mod_idP, rntiP);
    AssertError(0, 0, "Frame %d: find_UE_id(%u,rnti %d) not found\n", frameP, enb_mod_idP, rntiP);
  }
}

void rx_sdu(module_id_t enb_mod_idP,frame_t frameP,rnti_t rntiP,uint8_t *sdu, uint16_t sdu_len) {

  unsigned char  rx_ces[MAX_NUM_CE],num_ce,num_sdu,i,*payload_ptr;
  unsigned char  rx_lcids[NB_RB_MAX];
  unsigned short rx_lengths[NB_RB_MAX];
  module_id_t    ue_mod_id = find_UE_id(enb_mod_idP,rntiP);
  int ii,j;
  start_meas(&eNB_mac_inst[enb_mod_idP].rx_ulsch_sdu);
  
  if ((ue_mod_id >  NUMBER_OF_UE_MAX) || (ue_mod_id == -1) || (ue_mod_id == 255) )
  
  for(ii=0; ii<NB_RB_MAX; ii++) rx_lengths[ii] = 0;

  vcd_signal_dumper_dump_function_by_name(VCD_SIGNAL_DUMPER_FUNCTIONS_RX_SDU,1);

  LOG_D(MAC,"[eNB %d] Received ULSCH sdu from PHY (rnti %x, UE_id %d), parsing header\n",enb_mod_idP,rntiP,ue_mod_id);
  payload_ptr = parse_ulsch_header(sdu,&num_ce,&num_sdu,rx_ces,rx_lcids,rx_lengths,sdu_len);

  // control element
  for (i=0;i<num_ce;i++) {

    switch (rx_ces[i]) { // implement and process BSR + CRNTI +
    case POWER_HEADROOM:
      if (ue_mod_id != UE_INDEX_INVALID ){
	eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].phr_info =  (payload_ptr[0] & 0x3f);// - PHR_MAPPING_OFFSET;
	LOG_D(MAC, "[eNB] MAC CE_LCID %d : Received PHR PH = %d (db)\n", rx_ces[i], eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].phr_info);
      }
      payload_ptr+=sizeof(POWER_HEADROOM_CMD);
      break;
      case CRNTI:
        LOG_D(MAC, "[eNB] MAC CE_LCID %d : Received CRNTI %d \n", rx_ces[i], payload_ptr[0]);
        payload_ptr+=1;
        break;
    case TRUNCATED_BSR:
    case SHORT_BSR: {
      if (ue_mod_id  != UE_INDEX_INVALID ){
	uint8_t lcgid;
	lcgid = (payload_ptr[0] >> 6);
	LOG_D(MAC, "[eNB] MAC CE_LCID %d : Received short BSR LCGID = %u bsr = %d\n",
	      rx_ces[i], lcgid, payload_ptr[0] & 0x3f);
	eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[lcgid] = (payload_ptr[0] & 0x3f);
      }
      payload_ptr += 1;//sizeof(SHORT_BSR); // fixme
    } break;
    case LONG_BSR:
      if (ue_mod_id  != UE_INDEX_INVALID ){
	eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID0] = ((payload_ptr[0] & 0xFC) >> 2);
	eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID1] =
	  ((payload_ptr[0] & 0x03) << 4) | ((payload_ptr[1] & 0xF0) >> 4);
	eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID2] =
	  ((payload_ptr[1] & 0x0F) << 2) | ((payload_ptr[2] & 0xC0) >> 6);
	eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID3] = (payload_ptr[2] & 0x3F);
	LOG_D(MAC, "[eNB] MAC CE_LCID %d: Received long BSR LCGID0 = %u LCGID1 = "
	      "%u LCGID2 = %u LCGID3 = %u\n",
	      rx_ces[i],
	      eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID0],
	      eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID1],
	      eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID2],
	      eNB_mac_inst[enb_mod_idP].UE_template[ue_mod_id].bsr_info[LCGID3]);
      }
      payload_ptr += 3;////sizeof(LONG_BSR);
      break;
    default:
      LOG_E(MAC, "[eNB] Received unknown MAC header (0x%02x)\n", rx_ces[i]);
      break;
    }
  }
  
  for (i=0;i<num_sdu;i++) {
    LOG_D(MAC,"SDU Number %d MAC Subheader SDU_LCID %d, length %d\n",i,rx_lcids[i],rx_lengths[i]);
    
    switch (rx_lcids[i]) {
    case CCCH : 
      LOG_I(MAC,"[eNB %d][RAPROC] Frame %d, Received CCCH:  %x.%x.%x.%x.%x.%x, Terminating RA procedure for UE rnti %x\n",
	    enb_mod_idP,frameP,
	    payload_ptr[0],payload_ptr[1],payload_ptr[2],payload_ptr[3],payload_ptr[4], payload_ptr[5], rntiP);

      for (ii=0;ii<NB_RA_PROC_MAX;ii++) {
	LOG_D(MAC,"[RAPROC] Checking proc %d : rnti (%x, %x), active %d\n",ii,
	      eNB_mac_inst[enb_mod_idP].RA_template[ii].rnti, rntiP,
	      eNB_mac_inst[enb_mod_idP].RA_template[ii].RA_active);
	
	if ((eNB_mac_inst[enb_mod_idP].RA_template[ii].rnti==rntiP) &&
	    (eNB_mac_inst[enb_mod_idP].RA_template[ii].RA_active==TRUE)) {
	  
          //payload_ptr = parse_ulsch_header(msg3,&num_ce,&num_sdu,rx_ces,rx_lcids,rx_lengths,msg3_len);
	  
	  if (ue_mod_id == UE_INDEX_INVALID) {
	    memcpy(&eNB_mac_inst[enb_mod_idP].RA_template[ii].cont_res_id[0],payload_ptr,6);
	    LOG_I(MAC,"[eNB %d][RAPROC] Frame %d CCCH: Received RRCConnectionRequest: length %d, offset %d\n",
                  enb_mod_idP,frameP,rx_lengths[ii],payload_ptr-sdu);
	    if ((ue_mod_id=add_new_ue(enb_mod_idP,eNB_mac_inst[enb_mod_idP].RA_template[ii].rnti)) == -1 )
	      mac_xface->macphy_exit("[MAC][eNB] Max user count reached\n");
	    else 
	      LOG_I(MAC,"[eNB %d][RAPROC] Frame %d Added user with rnti %x => UE %d\n",
		    enb_mod_idP,frameP,eNB_mac_inst[enb_mod_idP].RA_template[ii].rnti,ue_mod_id);
	  } else {
	     LOG_I(MAC,"[eNB %d][RAPROC] Frame %d CCCH: Received RRCConnectionReestablishment from UE %d: length %d, offset %d\n",
		   enb_mod_idP,frameP,ue_mod_id,rx_lengths[ii],payload_ptr-sdu);
	  }
	  
	  if (Is_rrc_registered == 1)
	    mac_rrc_data_ind(enb_mod_idP,frameP,CCCH,(uint8_t *)payload_ptr,rx_lengths[ii],1,enb_mod_idP,0);
	  
	  
          if (num_ce >0) {  // handle msg3 which is not RRCConnectionRequest
	    //	process_ra_message(msg3,num_ce,rx_lcids,rx_ces);
	  }
	  
	  eNB_mac_inst[enb_mod_idP].RA_template[ii].generate_Msg4 = 1;
	  eNB_mac_inst[enb_mod_idP].RA_template[ii].wait_ack_Msg4 = 0;
	  
	  
	} // if process is active
	
      } // loop on RA processes
      
      break;
    case  DCCH : 
    case DCCH1 :
      //      if(eNB_mac_inst[module_idP].Dcch_lchan[UE_id].Active==1){
      
#if defined(ENABLE_MAC_PAYLOAD_DEBUG)
      LOG_T(MAC,"offset: %d\n",(unsigned char)((unsigned char*)payload_ptr-sdu));
      for (j=0;j<32;j++)
	LOG_T(MAC,"%x ",payload_ptr[j]);
      LOG_T(MAC,"\n");
#endif
      
      //  This check is just to make sure we didn't get a bogus SDU length, to be removed ...
      if (rx_lengths[i]<CCCH_PAYLOAD_SIZE_MAX) {
	LOG_D(MAC,"[eNB %d] Frame %d : ULSCH -> UL-DCCH, received %d bytes form UE %d on LCID %d(%d) \n",
	      enb_mod_idP,frameP, rx_lengths[i], ue_mod_id, rx_lcids[i], rx_lcids[i]);
	
	mac_rlc_data_ind(enb_mod_idP,ue_mod_id, frameP,ENB_FLAG_YES,MBMS_FLAG_NO,
			 rx_lcids[i],
			 (char *)payload_ptr,
			 rx_lengths[i],
			 1,
			 NULL);//(unsigned int*)crc_status);
	eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].num_pdu_rx[rx_lcids[i]]+=1;
	eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].num_bytes_rx[rx_lcids[i]]+=rx_lengths[i];
	
      }
      //      }
      break;
    case DTCH: // default DRB 
      //      if(eNB_mac_inst[module_idP].Dcch_lchan[UE_id].Active==1){
	
#if defined(ENABLE_MAC_PAYLOAD_DEBUG)
      LOG_T(MAC,"offset: %d\n",(unsigned char)((unsigned char*)payload_ptr-sdu));
      for (j=0;j<32;j++)
	LOG_T(MAC,"%x ",payload_ptr[j]);
      LOG_T(MAC,"\n");
#endif
      
      LOG_D(MAC,"[eNB %d] Frame %d : ULSCH -> UL-DTCH, received %d bytes from UE %d for lcid %d (%d)\n",
	    enb_mod_idP,frameP, rx_lengths[i], ue_mod_id,rx_lcids[i],rx_lcids[i]);
      
      if ((rx_lengths[i] <SCH_PAYLOAD_SIZE_MAX) &&  (rx_lengths[i] > 0) ) {   // MAX SIZE OF transport block
	mac_rlc_data_ind(enb_mod_idP,ue_mod_id, frameP,ENB_FLAG_YES,MBMS_FLAG_NO,
			 DTCH,
			 (char *)payload_ptr,
			   rx_lengths[i],
			 1,
			 NULL);//(unsigned int*)crc_status);
	eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].num_pdu_rx[rx_lcids[i]]+=1;
	eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].num_bytes_rx[rx_lcids[i]]+=rx_lengths[i];
	  
      }
	//      }
      break;
    default :  //if (rx_lcids[i] >= DTCH) {
      eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].num_errors_rx+=1;
      LOG_E(MAC,"[eNB %d] received unsupported or unknown LCID %d from UE %d ", rx_lcids[i], ue_mod_id);
      break;
    }
    payload_ptr+=rx_lengths[i];
    
  }

  eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].total_pdu_bytes_rx+=sdu_len;
  eNB_mac_inst[enb_mod_idP].eNB_UE_stats[ue_mod_id].total_num_pdus_rx+=1;
  
  vcd_signal_dumper_dump_function_by_name(VCD_SIGNAL_DUMPER_FUNCTIONS_RX_SDU,0);
  stop_meas(&eNB_mac_inst[enb_mod_idP].rx_ulsch_sdu);
}

unsigned char generate_dlsch_header(unsigned char *mac_header,
    unsigned char num_sdus,
    unsigned short *sdu_lengths,
    unsigned char *sdu_lcids,
    unsigned char drx_cmd,
    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 != 0) {
      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;
      ((TIMING_ADVANCE_CMD *)ce_ptr)->TA=timing_advance_cmd&0x3f;
      LOG_I(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);

}

/*
  #ifdef Rel10
  unsigned char generate_mch_header( unsigned char *mac_header,
  unsigned char num_sdus,
  unsigned short *sdu_lengths,
  unsigned char *sdu_lcids,
  unsigned char msi,
  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[2*num_sdus],*ce_ptr;

  ce_ptr = &mac_header_control_elements[0];

  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;
  }

  // SUBHEADER for MSI CE
  if (msi != 0) {// there is MSI MAC Control Element
  if (first_element>0) {
  mac_header_ptr->E = 1;
  mac_header_ptr+=last_size;
  }
  else {
  first_element = 1;
  }
  if (num_sdus*2 < 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 = MCH_SCHDL_INFO;
  ((SCH_SUBHEADER_SHORT *)mac_header_ptr)->L    = num_sdus*2;
  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 = MCH_SCHDL_INFO;
  ((SCH_SUBHEADER_LONG *)mac_header_ptr)->L    = (num_sdus*2)&0x7fff;
  last_size=3;
  }
  // Create the MSI MAC Control Element here
  }

  // SUBHEADER for MAC SDU (MCCH+MTCHs)
  for (i=0;i<num_sdus;i++) {
  if (first_element>0) {
  mac_header_ptr->E = 1;
  mac_header_ptr+=last_size;
  }
  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    = (unsigned short) sdu_lengths[i]&0x7fff;
  last_size=3;
  }
  }

  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;