From 6f2d90fee9cb842a02828d2bd0fba084336d8cde Mon Sep 17 00:00:00 2001
From: Robert Schmidt <robert.schmidt@openairinterface.org>
Date: Thu, 16 Apr 2026 14:52:03 +0200
Subject: [PATCH] Add nr_mac_pc_reset_snr() to harmonize SNR reset on first
 reception

---
 .../LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c  | 15 +++++++++++++++
 openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c    |  6 ++----
 openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c  |  4 +---
 openair2/LAYER2/NR_MAC_gNB/mac_proto.h            |  1 +
 4 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c
index 81e1ab1819..6be3e71b84 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c
@@ -4200,6 +4200,21 @@ void nr_mac_pc_snr(nr_power_control_t *pc, int snrx10, int rssi)
   pc->tpc_in_flight = PC_AVG_CNST * pc->tpc_in_flight; // + (1 - PC_AVG_CNST) * 0.0f
 }
 
+/**
+ * @brief Enter new SNR and RSSI value for the latest UL transmission as new
+ * fixed averages. Reset "TPC in flight" to zero.
+ *
+ * @param pc the power control loop
+ * @param snrx10 the current SNR measurement multiplied by 10
+ * @param rssi the current RSSI measurement
+ */
+void nr_mac_pc_reset_snr(nr_power_control_t *pc, int snrx10, int rssi)
+{
+  pc->avg_snr = 0.1f * snrx10;
+  pc->avg_rssi = rssi;
+  pc->tpc_in_flight = 0.0f;
+}
+
 /**
  * @brief Set a new target SNR for this power control loop, which can be
  * updated on a continuous basis, and will be reflected immediately upon
diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
index e85adc709d..d0ab235276 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
@@ -911,10 +911,8 @@ void handle_nr_uci_pucch_0_1(module_id_t mod_id, frame_t frame, slot_t slot, con
           return;
         }
         // Msg4 Ack: reset average with first measurement
-        if (uci_01->ul_cqi != 0xff) {
-          UE->UE_sched_ctrl.pucch_pc.avg_rssi = uci_01->rssi;
-          UE->UE_sched_ctrl.pucch_pc.avg_snr = (uci_01->ul_cqi * 5 - 640) * 0.1;
-        }
+        if (uci_01->ul_cqi != 0xff)
+          nr_mac_pc_reset_snr(&UE->UE_sched_ctrl.pucch_pc, uci_01->ul_cqi * 5 - 640, uci_01->rssi);
       }
       if (harq_confidence == 1) {
         UE->mac_stats.pucch0_DTX++;
diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c
index c3ae6eaedf..30213db346 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_ulsch.c
@@ -762,11 +762,9 @@ static void nr_rx_ra_sdu(const module_id_t mod_id,
   }
 
   if (ul_cqi != 0xff) {
-    NR_UE_sched_ctrl_t *sched_ctrl = &UE->UE_sched_ctrl;
     // Msg3: reset average with first measurement. If this fails (e.g., ul_cqi == 0xff)
     // everything starts from predetermined value
-    sched_ctrl->pusch_pc.avg_snr = 0.1 * (ul_cqi * 5 - 640);
-    sched_ctrl->pusch_pc.avg_rssi = rssi;
+    nr_mac_pc_reset_snr(&UE->UE_sched_ctrl.pusch_pc, ul_cqi * 5 - 640, rssi);
   }
 
   if (!sdu) { // NACK
diff --git a/openair2/LAYER2/NR_MAC_gNB/mac_proto.h b/openair2/LAYER2/NR_MAC_gNB/mac_proto.h
index fb2f12e6d2..5aeace199c 100644
--- a/openair2/LAYER2/NR_MAC_gNB/mac_proto.h
+++ b/openair2/LAYER2/NR_MAC_gNB/mac_proto.h
@@ -500,6 +500,7 @@ void post_process_ulsch(gNB_MAC_INST *nr_mac, post_process_pusch_t *pusch, NR_UE
 
 float nr_mac_get_snr(const nr_power_control_t *pc);
 void nr_mac_pc_snr(nr_power_control_t *pc, int snrx10, int rssi);
+void nr_mac_pc_reset_snr(nr_power_control_t *pc, int snrx10, int rssi);
 void nr_mac_set_target_snrx10(nr_power_control_t *pc, int target_snrx10);
 void nr_mac_set_rssi_threshold(nr_power_control_t *pc, int rssi_threshold);
 void nr_mac_signal_dtx(nr_power_control_t *pc);