Improve SIB1 length to support maximum value specified in 3GPP TS 38.331 section 5.2.1

The physical layer imposes a limit to the maximum size a SIB can take. The maximum SIB1 or SI message size is 2976 bits.

openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_bch.c

@@ -285,7 +285,7 @@ uint32_t schedule_control_sib1(module_id_t module_id,
                                int nrOfSymbols,
                                uint16_t dlDmrsSymbPos,
                                uint8_t candidate_idx,
-                               int num_total_bytes) {
+                               uint16_t num_total_bytes) {
 
   gNB_MAC_INST *gNB_mac = RC.nrmac[module_id];
   NR_COMMON_channels_t *cc = &gNB_mac->common_channels[CC_id];
@@ -570,7 +570,7 @@ void schedule_nr_sib1(module_id_t module_idP, frame_t frameP, sub_frame_t slotP)
 
       // Get SIB1
       uint8_t sib1_payload[NR_MAX_SIB_LENGTH/8];
-      uint8_t sib1_sdu_length = mac_rrc_nr_data_req(module_idP, CC_id, frameP, BCCH, SI_RNTI, 1, sib1_payload);
+      uint16_t sib1_sdu_length = mac_rrc_nr_data_req(module_idP, CC_id, frameP, BCCH, SI_RNTI, 1, sib1_payload);
       LOG_D(NR_MAC,"sib1_sdu_length = %i\n", sib1_sdu_length);
       LOG_D(NR_MAC,"SIB1: \n");
       for (int k=0;k<sib1_sdu_length;k++)
@@ -598,7 +598,8 @@ void schedule_nr_sib1(module_id_t module_idP, frame_t frameP, sub_frame_t slotP)
                                            startSymbolIndex,
                                            nrOfSymbols,
                                            dlDmrsSymbPos,
-                                           candidate_idx, sib1_sdu_length);
+                                           candidate_idx,
+                                           sib1_sdu_length);
 
       nfapi_nr_dl_tti_request_body_t *dl_req = &gNB_mac->DL_req[CC_id].dl_tti_request_body;
       int pdu_index = gNB_mac->pdu_index[0]++;

openair2/LAYER2/NR_MAC_gNB/mac_proto.h

@@ -93,7 +93,7 @@ uint32_t schedule_control_sib1(module_id_t module_id,
                                int nrOfSymbols,
                                uint16_t dlDmrsSymbPos,
                                uint8_t candidate_idx,
-                               int num_total_bytes);
+                               uint16_t num_total_bytes);
 
 /* \brief default FR1 DL preprocessor init routine, returns preprocessor to call */
 nr_pp_impl_dl nr_init_fr1_dlsch_preprocessor(module_id_t module_id, int CC_id);

openair2/RRC/NR/MESSAGES/asn1_msg.c

@@ -306,9 +306,8 @@ uint8_t do_MIB_NR(gNB_RRC_INST *rrc,uint32_t frame) {
   return((enc_rval.encoded+7)/8);
 }
 
-uint8_t do_SIB1_NR(rrc_gNB_carrier_data_t *carrier, 
-	               gNB_RrcConfigurationReq *configuration
-                  ) {
+uint16_t do_SIB1_NR(rrc_gNB_carrier_data_t *carrier, gNB_RrcConfigurationReq *configuration) {
+
   asn_enc_rval_t enc_rval;
 
   NR_BCCH_DL_SCH_Message_t *sib1_message = CALLOC(1,sizeof(NR_BCCH_DL_SCH_Message_t));
@@ -661,12 +660,9 @@ uint8_t do_SIB1_NR(rrc_gNB_carrier_data_t *carrier,
                                    (void *)sib1_message,
                                    carrier->SIB1,
                                    NR_MAX_SIB_LENGTH/8);
-  AssertFatal (enc_rval.encoded > 0, "ASN1 message encoding failed (%s, %lu)!\n",
+  AssertFatal(enc_rval.encoded > 0, "ASN1 message encoding failed (%s, %lu)!\n",
                enc_rval.failed_type->name, enc_rval.encoded);
-
-  if (enc_rval.encoded==-1) {
-    return(-1);
-  }
+  AssertFatal(enc_rval.encoded <= NR_MAX_SIB_LENGTH, "ASN1 encoded length %zd bits. 3GPP TS 38.331 section 5.2.1 - The physical layer imposes a limit to the maximum size a SIB can take. The maximum SIB1 or SI message size is 2976 bits.\n", enc_rval.encoded);
 
   return((enc_rval.encoded+7)/8);
 }

openair2/RRC/NR/MESSAGES/asn1_msg.h

@@ -73,9 +73,7 @@ uint8_t do_MIB_NR(gNB_RRC_INST *rrc,
 @param carrier pointer to Carrier information
 @param configuration Pointer Configuration Request structure  
 @return size of encoded bit stream in bytes*/
-uint8_t do_SIB1_NR(rrc_gNB_carrier_data_t *carrier,
-  gNB_RrcConfigurationReq *configuration
-                  );
+uint16_t do_SIB1_NR(rrc_gNB_carrier_data_t *carrier, gNB_RrcConfigurationReq *configuration);
 
 uint8_t do_SIB23_NR(rrc_gNB_carrier_data_t *carrier,
                     gNB_RrcConfigurationReq *configuration);

openair2/RRC/NR/nr_rrc_defs.h

@@ -435,7 +435,7 @@ typedef struct {
   uint8_t                                   sizeof_MIB;
 
   uint8_t                                   *SIB1;
-  uint8_t                                   sizeof_SIB1;
+  uint16_t                                  sizeof_SIB1;
 
   uint8_t                                   *SIB23;
   uint8_t                                   sizeof_SIB23;