add the prach fit checks for PRB=6

srsenb/src/enb.cc

@@ -217,16 +217,24 @@ bool enb::init(all_args_t *args_)
 
   uint32_t prach_freq_offset = rrc_cfg.sibs[1].sib.sib2.rr_config_common_sib.prach_cnfg.prach_cnfg_info.prach_freq_offset;
 
-  if (prach_freq_offset + 6 > cell_cfg.nof_prb) {
+  if(cell_cfg.nof_prb>10) {
+    if (prach_freq_offset + 6 > cell_cfg.nof_prb - SRSLTE_MAX(rrc_cfg.cqi_cfg.nof_prb, rrc_cfg.sr_cfg.nof_prb)) {
       fprintf(stderr, "Invalid PRACH configuration: frequency offset=%d outside bandwidth limits\n", prach_freq_offset);
       return false;
     }
 
-  if (prach_freq_offset < rrc_cfg.cqi_cfg.nof_prb || prach_freq_offset < rrc_cfg.sr_cfg.nof_prb ) {
+    if (prach_freq_offset < SRSLTE_MAX(rrc_cfg.cqi_cfg.nof_prb, rrc_cfg.sr_cfg.nof_prb)) {
       fprintf(stderr, "Invalid PRACH configuration: frequency offset=%d lower than CQI offset: %d or SR offset: %d\n",
               prach_freq_offset, rrc_cfg.cqi_cfg.nof_prb, rrc_cfg.sr_cfg.nof_prb);
       return false;
     }
+  } else { // 6 PRB case
+    if (prach_freq_offset+6 > cell_cfg.nof_prb) {
+      fprintf(stderr, "Invalid PRACH configuration: frequency interval=(%d, %d) does not fit into the eNB PRBs=(0,%d)\n",
+              prach_freq_offset, prach_freq_offset+6, cell_cfg.nof_prb);
+      return false;
+    }
+  }
 
   rrc_cfg.inactivity_timeout_ms = args->expert.rrc_inactivity_timer;
   rrc_cfg.enable_mbsfn =  args->expert.enable_mbsfn;

srsenb/src/mac/scheduler.cc

@@ -796,7 +796,7 @@ int sched::ul_sched(uint32_t tti, srsenb::sched_interface::ul_sched_res_t* sched
     return 0; 
   }
 
-  if (cfg.prach_freq_offset + 6 > cfg.cell.nof_prb) {
+  if (cfg.prach_freq_offset + 6 > cfg.cell.nof_prb and cfg.cell.nof_prb>10) {
     fprintf(stderr, "Invalid PRACH configuration: frequency offset=%d outside bandwidth limits\n", cfg.prach_freq_offset);
     return -1;
   }