/* * 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 PHY/LTE_TRANSPORT/dlsch_scrambling.c * \brief Routines for the scrambling procedure of the PDSCH physical channel from 36-211, V8.6 2009-03 * \author R. Knopp * \date 2011 * \version 0.1 * \company Eurecom * \email: knopp@eurecom.fr,florian.kaltenberger@eurecom.fr * \note * \warning */ //#define DEBUG_SCRAMBLING 1 #include "PHY/defs_eNB.h" #include "PHY/defs_UE.h" #include "PHY/LTE_REFSIG/lte_refsig.h" #include "PHY/CODING/coding_extern.h" #include "PHY/CODING/lte_interleaver_inline.h" #include "transport_eNB.h" #include "PHY/phy_extern.h" #include "common/utils/LOG/vcd_signal_dumper.h" void dlsch_scrambling(LTE_DL_FRAME_PARMS *frame_parms, int mbsfn_flag, LTE_eNB_DLSCH_t *dlsch, int harq_pid, int G, uint8_t q, uint16_t frame, uint8_t Ns) { int n; // uint8_t reset; uint32_t x1, x2, s=0; uint8_t *dlsch_e=dlsch->harq_processes[harq_pid]->e; uint8_t *e=dlsch_e; VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_ENB_DLSCH_SCRAMBLING, VCD_FUNCTION_IN); // Rule for accumulation of subframes for BL/CE UEs uint8_t Nacc=4; uint16_t j0,j,idelta; uint16_t i = (Ns>>1) + (10*frame); #ifdef PHY_TX_THREAD uint16_t i0 = dlsch->harq_processes[harq_pid]->i0; #else uint16_t i0 = dlsch->i0; #endif #ifdef PHY_TX_THREAD if (dlsch->harq_processes[harq_pid]->sib1_br_flag==1) Nacc=1; #else if (dlsch->sib1_br_flag==1) Nacc=1; #endif else if (dlsch->rnti == 0xFFFF || dlsch->rnti == 0xFFFE) Nacc = (frame_parms->frame_type == TDD) ? 10 : 4; #ifdef PHY_TX_THREAD // Note: above SC-RNTI will also have to be added when/if implemented else if (dlsch->harq_processes[harq_pid]->CEmode == CEmodeA) Nacc=1; else if (dlsch->harq_processes[harq_pid]->CEmode == CEmodeB) Nacc = (frame_parms->frame_type == TDD) ? 10 : 4; #else // Note: above SC-RNTI will also have to be added when/if implemented else if (dlsch->CEmode == CEmodeA) Nacc=1; else if (dlsch->CEmode == CEmodeB) Nacc = (frame_parms->frame_type == TDD) ? 10 : 4; #endif if (frame_parms->frame_type == FDD || Nacc == 1) idelta = 0; else idelta = Nacc-2; j0 = (i0+idelta)/Nacc; j = (i - i0)/Nacc; // reset = 1; // x1 is set in lte_gold_generic if (mbsfn_flag == 0) { #ifdef PHY_TX_THREAD if (dlsch->harq_processes[harq_pid]->i0 != 0xFFFF) { #else if (dlsch->i0 != 0xFFFF) { #endif // rule for BL/CE UEs from Section 6.3.1 in 36.211 x2= (dlsch->rnti<<14) + (q<<13) + ((((j0+j)*Nacc)%10)<<9) + frame_parms->Nid_cell; if ((frame&1023) < 200) LOG_D(PHY,"Scrambling init for (i0 %d, i %d, j0 %d, j %d, Nacc %d) => x2 %d\n",i0,i,j0,j,Nacc,x2); } else x2 = (dlsch->rnti<<14) + (q<<13) + ((Ns>>1)<<9) + frame_parms->Nid_cell; //this is c_init in 36.211 Sec 6.3.1 for PDSCH } else { x2 = ((Ns>>1)<<9) + frame_parms->Nid_cell_mbsfn; //this is c_init in 36.211 Sec 6.3.1 for PMCH } #ifdef DEBUG_SCRAMBLING printf("scrambling: i0 %d rnti %x, q %d, Ns %d, Nid_cell %d, G %d x2 %x\n",dlsch->i0,dlsch->rnti,q,Ns,frame_parms->Nid_cell, G, x2); #endif s = lte_gold_generic(&x1, &x2, 1); for (n=0; n<(1+(G>>5)); n++) { #ifdef DEBUG_SCRAMBLING for (int k=0; k<32; k++) printf("scrambling %d : %d xor %d = %d\n",k+(n<<5),e[k],(s>>k)&1,e[k]^((s>>k)&1)); #endif e[0] = (e[0]) ^ (s&1); e[1] = (e[1]) ^ ((s>>1)&1); e[2] = (e[2]) ^ ((s>>2)&1); e[3] = (e[3]) ^ ((s>>3)&1); e[4] = (e[4]) ^ ((s>>4)&1); e[5] = (e[5]) ^ ((s>>5)&1); e[6] = (e[6]) ^ ((s>>6)&1); e[7] = (e[7]) ^ ((s>>7)&1); e[8] = (e[8]) ^ ((s>>8)&1); e[9] = (e[9]) ^ ((s>>9)&1); e[10] = (e[10]) ^ ((s>>10)&1); e[11] = (e[11]) ^ ((s>>11)&1); e[12] = (e[12]) ^ ((s>>12)&1); e[13] = (e[13]) ^ ((s>>13)&1); e[14] = (e[14]) ^ ((s>>14)&1); e[15] = (e[15]) ^ ((s>>15)&1); e[16] = (e[16]) ^ ((s>>16)&1); e[17] = (e[17]) ^ ((s>>17)&1); e[18] = (e[18]) ^ ((s>>18)&1); e[19] = (e[19]) ^ ((s>>19)&1); e[20] = (e[20]) ^ ((s>>20)&1); e[21] = (e[21]) ^ ((s>>21)&1); e[22] = (e[22]) ^ ((s>>22)&1); e[23] = (e[23]) ^ ((s>>23)&1); e[24] = (e[24]) ^ ((s>>24)&1); e[25] = (e[25]) ^ ((s>>25)&1); e[26] = (e[26]) ^ ((s>>26)&1); e[27] = (e[27]) ^ ((s>>27)&1); e[28] = (e[28]) ^ ((s>>28)&1); e[29] = (e[29]) ^ ((s>>29)&1); e[30] = (e[30]) ^ ((s>>30)&1); e[31] = (e[31]) ^ ((s>>31)&1); // This is not faster for some unknown reason // ((__m128i *)e)[0] = _mm_xor_si128(((__m128i *)e)[0],((__m128i *)scrambling_lut)[s&65535]); // ((__m128i *)e)[1] = _mm_xor_si128(((__m128i *)e)[1],((__m128i *)scrambling_lut)[s>>16]); s = lte_gold_generic(&x1, &x2, 0); e += 32; } VCD_SIGNAL_DUMPER_DUMP_FUNCTION_BY_NAME(VCD_SIGNAL_DUMPER_FUNCTIONS_ENB_DLSCH_SCRAMBLING, VCD_FUNCTION_OUT); } void init_scrambling_lut(void) { uint32_t s; int i=0,j; for (s=0; s<=65535; s++) { for (j=0; j<16; j++) { scrambling_lut[i++] = (uint8_t)((s>>j)&1); } } } void dlsch_unscrambling(LTE_DL_FRAME_PARMS *frame_parms, int mbsfn_flag, LTE_UE_DLSCH_t *dlsch, int G, int16_t *llr, uint8_t q, uint8_t Ns) { int i,j,k=0; // uint8_t reset; uint32_t x1, x2, s=0; // reset = 1; // x1 is set in first call to lte_gold_generic if (mbsfn_flag == 0) x2 = (dlsch->rnti<<14) + (q<<13) + ((Ns>>1)<<9) + frame_parms->Nid_cell; //this is c_init in 36.211 Sec 6.3.1 else x2 = ((Ns>>1)<<9) + frame_parms->Nid_cell_mbsfn; //this is c_init in 36.211 Sec 6.3.1 #ifdef DEBUG_SCRAMBLING printf("unscrambling: rnti %x, q %d, Ns %d, Nid_cell %d G %d, x2 %x\n",dlsch->rnti,q,Ns,frame_parms->Nid_cell,G,x2); #endif s = lte_gold_generic(&x1, &x2, 1); for (i=0; i<(1+(G>>5)); i++) { for (j=0; j<32; j++,k++) { #ifdef DEBUG_SCRAMBLING printf("unscrambling %d : %d xor %d =",k,llr[k],(s>>j)&1); #endif llr[k] = ((2*((s>>j)&1))-1)*llr[k]; #ifdef DEBUG_SCRAMBLING printf("%d\n",llr[k]); #endif } s = lte_gold_generic(&x1, &x2, 0); } } void init_unscrambling_lut(void) { uint32_t s; int i=0,j; for (s=0; s<=65535; s++) { for (j=0; j<16; j++) { unscrambling_lut[i++] = (int16_t)((((s>>j)&1)<<1)-1); } } }