hw-mgmt: scripts: Load mlxreg-dpu as part of platform init

In very rare scenarios, especially in the first boot after the
NOS installation, i2c buses for the DPUs are not ready when
the mlxreg-dpu driver completes the probing. Even though, we
have the delayed probing enabled in the mlxreg-dpu driver, the
race condition can occur and dpu driver doesn't see a fully
setup multiplexed i2c bus.

This patch adds a blacklist entry for mlxreg-dpu driver
and load it as part of smart switch platform initialization.

Bug #4850549

Signed-off-by: Ciju Rajan K <crajank@nvidia.com>

Author: ciju-nvidia

usr/usr/bin/hw-management.sh

@@ -2417,6 +2417,7 @@ qm_qm3_common()
 
 smart_switch_common()
 {
+	modprobe mlxreg-dpu
 	if [ ! -e "$devtree_file" ]; then
 		connect_table+=(${msn4700_msn4600_A1_base_connect_table[@]})
 		add_cpu_board_to_connection_table $smart_switch_cpu_bus_offset

usr/usr/local/bin/hw-management-process-blacklist.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 ################################################################################
 # SPDX-FileCopyrightText: NVIDIA CORPORATION & AFFILIATES
-# Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# Copyright (c) 2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met:
@@ -33,7 +33,7 @@
 
 __default_blacklist="
 ##################################################################################
-# Copyright (c) 2018-2025, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# Copyright (c) 2018-2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 #
 options at24 io_limit=32
 options gpio_ich gpiobase=0
@@ -91,6 +91,7 @@ process_blacklist()
 		echo blacklist i2c_designware_platform >> $BLACKLIST_FILE
 		echo blacklist i2c_designware_core >> $BLACKLIST_FILE
 		echo blacklist i2c_asf >> $BLACKLIST_FILE
+		echo blacklist mlxreg_dpu >> $BLACKLIST_FILE
 		;;
 	esac
 }