/* * 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/NR_TRANSPORT/nr_dci.c * \brief Implements DCI encoding and PDCCH TX procedures (38.212/38.213/38.214). V15.4.0 2019-01. * \author Guy De Souza * \date 2018 * \version 0.1 * \company Eurecom * \email: desouza@eurecom.fr * \note * \warning */ #include "nr_dci.h" #include "nr_dlsch.h" #include "nr_sch_dmrs.h" #include "PHY/MODULATION/nr_modulation.h" //#define DEBUG_PDCCH_DMRS //#define DEBUG_DCI //#define DEBUG_CHANNEL_CODING void nr_pdcch_scrambling(uint32_t *in, uint32_t size, uint32_t Nid, uint32_t scrambling_RNTI, uint32_t *out) { uint8_t reset; uint32_t x1, x2, s=0; reset = 1; x2 = (scrambling_RNTI<<16) + Nid; LOG_D(PHY,"PDCCH Scrambling x2 %x : scrambling_RNTI %x \n", x2, scrambling_RNTI); for (int i=0; i<size; i++) { if ((i&0x1f)==0) { s = lte_gold_generic(&x1, &x2, reset); reset = 0; if (i) { in++; out++; } } (*out) ^= ((((*in)>>(i&0x1f))&1) ^ ((s>>(i&0x1f))&1))<<(i&0x1f); } } void nr_generate_dci(PHY_VARS_gNB *gNB, nfapi_nr_dl_tti_pdcch_pdu_rel15_t *pdcch_pdu_rel15, uint32_t **gold_pdcch_dmrs, int32_t *txdataF, int16_t amp, NR_DL_FRAME_PARMS frame_parms) { int16_t mod_dmrs[NR_MAX_CSET_DURATION][NR_MAX_PDCCH_DMRS_LENGTH>>1] __attribute__((aligned(16))); // 3 for the max coreset duration uint16_t cset_start_sc; uint8_t cset_start_symb, cset_nsymb; int k,l,k_prime,dci_idx, dmrs_idx; // find coreset descriptor int rb_offset; int n_rb; // compute rb_offset and n_prb based on frequency allocation nr_fill_cce_list(gNB,0,pdcch_pdu_rel15); get_coreset_rballoc(pdcch_pdu_rel15->FreqDomainResource,&n_rb,&rb_offset); cset_start_sc = frame_parms.first_carrier_offset + (pdcch_pdu_rel15->BWPStart + rb_offset) * NR_NB_SC_PER_RB; for (int d=0;d<pdcch_pdu_rel15->numDlDci;d++) { /*The coreset is initialised * in frequency: the first subcarrier is obtained by adding the first CRB overlapping the SSB and the rb_offset for coreset 0 * or the rb_offset for other coresets * in time: by its first slot and its first symbol*/ const nfapi_nr_dl_dci_pdu_t *dci_pdu = &pdcch_pdu_rel15->dci_pdu[d]; cset_start_symb = pdcch_pdu_rel15->StartSymbolIndex; cset_nsymb = pdcch_pdu_rel15->DurationSymbols; dci_idx = 0; LOG_D(PHY, "Coreset rb_offset %d, nb_rb %d BWP Start %d\n",rb_offset,n_rb,pdcch_pdu_rel15->BWPStart); LOG_D(PHY, "Coreset starting subcarrier %d on symbol %d (%d symbols)\n", cset_start_sc, cset_start_symb, cset_nsymb); // DMRS length is per OFDM symbol uint32_t dmrs_length = n_rb*6; //2(QPSK)*3(per RB)*6(REG per CCE) uint32_t encoded_length = dci_pdu->AggregationLevel*108; //2(QPSK)*9(per RB)*6(REG per CCE) LOG_D(PHY, "DMRS length per symbol %d\t DCI encoded length %d (precoder_granularity %d,reg_mapping %d)\n", dmrs_length, encoded_length,pdcch_pdu_rel15->precoderGranularity,pdcch_pdu_rel15->CceRegMappingType); dmrs_length += rb_offset*6; // To accommodate more DMRS symbols in case of rb offset /// DMRS QPSK modulation for (int symb=cset_start_symb; symb<cset_start_symb + pdcch_pdu_rel15->DurationSymbols; symb++) { nr_modulation(gold_pdcch_dmrs[symb], dmrs_length, DMRS_MOD_ORDER, mod_dmrs[symb]); //Qm = 2 as DMRS is QPSK modulated #ifdef DEBUG_PDCCH_DMRS for (int i=0; i<dmrs_length>>1; i++) printf("symb %d i %d gold seq 0x%08x mod_dmrs %d %d\n", symb, i, gold_pdcch_dmrs[symb][i>>5], mod_dmrs[symb][i<<1], mod_dmrs[symb][(i<<1)+1] ); #endif } /// DCI payload processing // CRC attachment + Scrambling + Channel coding + Rate matching uint32_t encoder_output[NR_MAX_DCI_SIZE_DWORD]; uint16_t n_RNTI = dci_pdu->RNTI; uint16_t Nid = dci_pdu->ScramblingId; uint16_t scrambling_RNTI = dci_pdu->ScramblingRNTI; t_nrPolar_params *currentPtr = nr_polar_params(NR_POLAR_DCI_MESSAGE_TYPE, dci_pdu->PayloadSizeBits, dci_pdu->AggregationLevel, 0,NULL); polar_encoder_fast((uint64_t*)dci_pdu->Payload, (void*)encoder_output, n_RNTI,1,currentPtr); #ifdef DEBUG_CHANNEL_CODING printf("polar rnti %x,length %d, L %d\n",n_RNTI, dci_pdu->PayloadSizeBits,pdcch_pdu_rel15->dci_pdu.AggregationLevel[d]); printf("DCI PDU: [0]->0x%lx \t [1]->0x%lx\n", ((uint64_t*)dci_pdu->Payload)[0], ((uint64_t*)dci_pdu->Payload)[1]); printf("Encoded Payload (length:%d dwords):\n", encoded_length>>5); for (int i=0; i<encoded_length>>5; i++) printf("[%d]->0x%08x \t", i,encoder_output[i]); printf("\n"); #endif /// Scrambling uint32_t scrambled_output[NR_MAX_DCI_SIZE_DWORD]= {0}; nr_pdcch_scrambling(encoder_output, encoded_length, Nid, scrambling_RNTI, scrambled_output); #ifdef DEBUG_CHANNEL_CODING printf("scrambled output: [0]->0x%08x \t [1]->0x%08x \t [2]->0x%08x \t [3]->0x%08x\t [4]->0x%08x\t [5]->0x%08x\t \ [6]->0x%08x \t [7]->0x%08x \t [8]->0x%08x \t [9]->0x%08x\t [10]->0x%08x\t [11]->0x%08x\n", scrambled_output[0], scrambled_output[1], scrambled_output[2], scrambled_output[3], scrambled_output[4],scrambled_output[5], scrambled_output[6], scrambled_output[7], scrambled_output[8], scrambled_output[9], scrambled_output[10],scrambled_output[11] ); #endif /// QPSK modulation int16_t mod_dci[NR_MAX_DCI_SIZE>>1] __attribute__((aligned(16))); nr_modulation(scrambled_output, encoded_length, DMRS_MOD_ORDER, mod_dci); //Qm = 2 as DMRS is QPSK modulated #ifdef DEBUG_DCI for (int i=0; i<encoded_length>>1; i++) printf("i %d mod_dci %d %d\n", i, mod_dci[i<<1], mod_dci[(i<<1)+1] ); #endif /// Resource mapping if (cset_start_sc >= frame_parms.ofdm_symbol_size) cset_start_sc -= frame_parms.ofdm_symbol_size; // Get cce_list indices by reg_idx in ascending order int reg_list_index = 0; int reg_list_order[NR_MAX_PDCCH_AGG_LEVEL] = {}; for (int p = 0; p < NR_MAX_PDCCH_AGG_LEVEL; p++) { for(int p2 = 0; p2 < dci_pdu->AggregationLevel; p2++) { if(gNB->cce_list[d][p2].reg_list[0].reg_idx == p * NR_NB_REG_PER_CCE) { reg_list_order[reg_list_index] = p2; reg_list_index++; break; } } } /*Mapping the encoded DCI along with the DMRS */ for(int symbol_idx = 0; symbol_idx < pdcch_pdu_rel15->DurationSymbols; symbol_idx++) { for (int cce_count = 0; cce_count < dci_pdu->AggregationLevel; cce_count+=pdcch_pdu_rel15->DurationSymbols) { int8_t cce_idx = reg_list_order[cce_count]; for (int reg_in_cce_idx = 0; reg_in_cce_idx < NR_NB_REG_PER_CCE; reg_in_cce_idx++) { k = cset_start_sc + gNB->cce_list[d][cce_idx].reg_list[reg_in_cce_idx].start_sc_idx; if (k >= frame_parms.ofdm_symbol_size) k -= frame_parms.ofdm_symbol_size; l = cset_start_symb + symbol_idx; // dmrs index depends on reference point for k according to 38.211 7.4.1.3.2 if (pdcch_pdu_rel15->CoreSetType == NFAPI_NR_CSET_CONFIG_PDCCH_CONFIG) dmrs_idx = (gNB->cce_list[d][cce_idx].reg_list[reg_in_cce_idx].reg_idx) * 3; else dmrs_idx = (gNB->cce_list[d][cce_idx].reg_list[reg_in_cce_idx].reg_idx + rb_offset) * 3; k_prime = 0; for (int m = 0; m < NR_NB_SC_PER_RB; m++) { if (m == (k_prime << 2) + 1) { // DMRS if not already mapped ((int16_t *) txdataF)[(l * frame_parms.ofdm_symbol_size + k) << 1] = (amp * mod_dmrs[l][dmrs_idx << 1]) >> 15; ((int16_t *) txdataF)[((l * frame_parms.ofdm_symbol_size + k) << 1) + 1] = (amp * mod_dmrs[l][(dmrs_idx << 1) + 1]) >> 15; #ifdef DEBUG_PDCCH_DMRS printf("PDCCH DMRS: l %d position %d => (%d,%d)\n",l,k,((int16_t *)txdataF)[(l*frame_parms.ofdm_symbol_size + k)<<1], ((int16_t *)txdataF)[((l*frame_parms.ofdm_symbol_size + k)<<1)+1]); #endif dmrs_idx++; k_prime++; } else { // DCI payload ((int16_t *) txdataF)[(l * frame_parms.ofdm_symbol_size + k) << 1] = (amp * mod_dci[dci_idx << 1]) >> 15; ((int16_t *) txdataF)[((l * frame_parms.ofdm_symbol_size + k) << 1) + 1] = (amp * mod_dci[(dci_idx << 1) + 1]) >> 15; #ifdef DEBUG_DCI printf("PDCCH: l %d position %d => (%d,%d)\n",l,k,((int16_t *)txdataF)[(l*frame_parms.ofdm_symbol_size + k)<<1], ((int16_t *)txdataF)[((l*frame_parms.ofdm_symbol_size + k)<<1)+1]); #endif dci_idx++; } k++; if (k >= frame_parms.ofdm_symbol_size) k -= frame_parms.ofdm_symbol_size; } // m } // reg_in_cce_idx } // cce_count } // symbol_idx LOG_D(PHY, "DCI: payloadSize = %d | payload = %llx\n", dci_pdu->PayloadSizeBits, *(unsigned long long *)dci_pdu->Payload); } // for (int d=0;d<pdcch_pdu_rel15->numDlDci;d++) } void nr_generate_dci_top(PHY_VARS_gNB *gNB, nfapi_nr_dl_tti_pdcch_pdu *pdcch_pdu, nfapi_nr_dl_tti_pdcch_pdu *ul_dci_pdu, uint32_t **gold_pdcch_dmrs, int32_t *txdataF, int16_t amp, NR_DL_FRAME_PARMS frame_parms) { AssertFatal(pdcch_pdu!=NULL || ul_dci_pdu!=NULL,"At least one pointer has to be !NULL\n"); if (pdcch_pdu) { nr_generate_dci(gNB,&pdcch_pdu->pdcch_pdu_rel15,gold_pdcch_dmrs,txdataF,amp,frame_parms); } if (ul_dci_pdu) { nr_generate_dci(gNB,&ul_dci_pdu->pdcch_pdu_rel15,gold_pdcch_dmrs,txdataF,amp,frame_parms); } }