nr,gnb,sched: fix sib1 window derivation in NR sched

srsgnb/hdr/stack/mac/sched_nr_signalling.h

@@ -63,7 +63,7 @@ private:
   srslog::basic_logger& logger;
 
   struct si_msg_ctxt_t {
-    uint32_t     n       = 0; /// index in schedulingInfoList in si-SchedulingInfo in SIB1
+    uint32_t     n       = 0; /// 0 for SIB1, n/index in schedulingInfoList in si-SchedulingInfo in SIB1
     uint32_t     len     = 0;
     uint32_t     win_len = 0;
     uint32_t     period  = 0;
@@ -71,7 +71,7 @@ private:
     alloc_result result  = alloc_result::invalid_coderate; /// last attempt to schedule SI
     slot_point   win_start;                                /// start of SI window, invalid if outside
   };
-  srsran::bounded_vector<si_msg_ctxt_t, 10> pending_sis;
+  srsran::bounded_vector<si_msg_ctxt_t, 10> pending_sis; /// configured SIB1 and SI messages
 };
 
 } // namespace sched_nr_impl

srsgnb/src/stack/mac/sched_nr_signalling.cc

@@ -123,7 +123,14 @@ bool fill_dci_sib(prb_interval interv, uint32_t sib_id, const bwp_params_t& bwp_
 
 si_sched::si_sched(const bwp_params_t& bwp_cfg_) :
   bwp_cfg(&bwp_cfg_), logger(srslog::fetch_basic_logger(bwp_cfg_.sched_cfg.logger_name))
-{}
+{
+  // TODO: Get SIB1 other SI msgs config from RRC
+  pending_sis.emplace_back();
+  pending_sis[0].n       = 0;
+  pending_sis[0].len     = 77;
+  pending_sis[0].period  = 160;
+  pending_sis[0].win_len = 1;
+}
 
 void si_sched::run_slot(bwp_slot_allocator& bwp_alloc)
 {
@@ -136,37 +143,40 @@ void si_sched::run_slot(bwp_slot_allocator& bwp_alloc)
   slot_point        sl_pdcch      = bwp_alloc.get_pdcch_tti();
   const prb_bitmap& prbs          = bwp_alloc.res_grid()[sl_pdcch].dl_prbs.prbs();
 
-  // SIB1 case
-  if (sl_pdcch.to_uint() % 160 == 0) {
-    // TODO: compute if SIB1 slot based on config
-    const uint32_t aggr_lvl_idx = 2;
-    const uint32_t sib_id       = 1;
-    const uint32_t sib1len      = 77; // TODO: extract from config
-    alloc_result   ret          = bwp_alloc.alloc_si(aggr_lvl_idx, sib_id, sib1len, prb_interval{0, 7});
-    if (ret != alloc_result::success) {
-      bwp_alloc.logger.warning("SCHED: Cannot allocate SIB1.");
-    }
-  }
-
   // Update SI windows
   uint32_t N = bwp_cfg->slots.size();
   for (si_msg_ctxt_t& si : pending_sis) {
     uint32_t x = (si.n - 1) * si.win_len;
 
-    if (not si.win_start.valid() and (sl_pdcch.sfn() % si.period == x / N) and
-        sl_pdcch.slot_idx() == x % bwp_cfg->slots.size()) {
+    if (not si.win_start.valid()) {
+      bool start_window;
+      if (si.n == 0) {
+        // SIB1
+        start_window = sl_pdcch.to_uint() % si.period == 0;
+      } else {
+        // SI messages
+        start_window = (sl_pdcch.sfn() % si.period == x / N) and sl_pdcch.slot_idx() == x % bwp_cfg->slots.size();
+      }
+      if (start_window) {
         // If start of SI message window
         si.win_start = sl_pdcch;
-    } else if (si.win_start.valid() and si.win_start + si.win_len >= sl_pdcch) {
+      }
+    } else if (si.win_start + si.win_len >= sl_pdcch) {
       // If end of SI message window
+      if (si.n == 0) {
+        logger.error("SCHED: Could not allocate SIB1, len=%d. Cause: %s", si.n, si.len, to_string(si.result));
+      } else {
         logger.warning(
             "SCHED: Could not allocate SI message idx=%d, len=%d. Cause: %s", si.n, si.len, to_string(si.result));
+      }
       si.win_start.clear();
     }
   }
 
-  // Schedule pending SIs
-  if (bwp_cfg->slots[sl_pdcch.slot_idx()].is_dl) {
+  // Schedule pending SIBs
+  if (not bwp_cfg->slots[sl_pdcch.slot_idx()].is_dl) {
+    return;
+  }
   for (si_msg_ctxt_t& si : pending_sis) {
     if (not si.win_start.valid()) {
       continue;
@@ -190,6 +200,10 @@ void si_sched::run_slot(bwp_slot_allocator& bwp_alloc)
         // SIB scheduled successfully
         si.win_start.clear();
         si.n_tx++;
+        if (si.n == 0) {
+          logger.debug("SCHED: Allocated SIB1, len=%d.", si.n, si.len);
+        } else {
+          logger.debug("SCHED: Allocated SI message idx=%d, len=%d.", si.n, si.len);
         }
       }
     }