diff --git a/package-21.02/kernel/tops/src/ser.c b/package-21.02/kernel/tops/src/ser.c
new file mode 100644
index 0000000..a126185
--- /dev/null
+++ b/package-21.02/kernel/tops/src/ser.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2023 MediaTek Inc. All Rights Reserved.
+ *
+ * Author: Alvin Kuo <alvin.kuog@mediatek.com>
+ */
+
+#include <linux/err.h>
+#include <linux/workqueue.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+
+#include "internal.h"
+#include "net-event.h"
+#include "ser.h"
+#include "trm.h"
+
+struct tops_ser {
+	struct work_struct work;
+	struct tops_ser_params ser_params;
+	spinlock_t params_lock;
+};
+
+struct tops_ser tops_ser;
+
+static inline void __mtk_tops_ser_cmd_clear(void)
+{
+	memset(&tops_ser.ser_params, 0, sizeof(struct tops_ser_params));
+	tops_ser.ser_params.type = __TOPS_SER_TYPE_MAX;
+}
+
+static inline void mtk_tops_ser_cmd_clear(void)
+{
+	unsigned long flag;
+
+	spin_lock_irqsave(&tops_ser.params_lock, flag);
+
+	__mtk_tops_ser_cmd_clear();
+
+	spin_unlock_irqrestore(&tops_ser.params_lock, flag);
+}
+
+static void mtk_tops_ser_setup_mcmd(struct tops_ser_params *ser_params,
+				    struct mcu_ctrl_cmd *mcmd)
+{
+	memset(mcmd, 0, sizeof(struct mcu_ctrl_cmd));
+
+	switch (ser_params->type) {
+	case TOPS_SER_NETSYS_FE_RST:
+		mcmd->e = MCU_EVENT_TYPE_FE_RESET;
+		break;
+	case TOPS_SER_WDT_TO:
+		mcmd->e = MCU_EVENT_TYPE_WDT_TIMEOUT;
+		break;
+	default:
+		TOPS_ERR("unsupport TOPS SER type: %u\n", ser_params->type);
+		return;
+	}
+
+	if (ser_params->ser_mcmd_setup)
+		ser_params->ser_mcmd_setup(ser_params, mcmd);
+}
+
+static void mtk_tops_ser_reset_callback(void *params)
+{
+	struct tops_ser_params *ser_params = params;
+
+	if (ser_params->ser_callback)
+		ser_params->ser_callback(ser_params);
+}
+
+static void mtk_tops_ser_work(struct work_struct *work)
+{
+	struct tops_ser_params ser_params;
+	struct mcu_ctrl_cmd mcmd;
+	unsigned long flag = 0;
+
+	spin_lock_irqsave(&tops_ser.params_lock, flag);
+
+	while (tops_ser.ser_params.type != __TOPS_SER_TYPE_MAX) {
+		memcpy(&ser_params,
+		       &tops_ser.ser_params,
+		       sizeof(struct tops_ser_params));
+
+		spin_unlock_irqrestore(&tops_ser.params_lock, flag);
+
+		mtk_tops_ser_setup_mcmd(&ser_params, &mcmd);
+
+		if (mtk_tops_mcu_reset(&mcmd,
+				       mtk_tops_ser_reset_callback,
+				       &ser_params)) {
+			TOPS_INFO("SER type: %u failed to recover\n",
+				  ser_params.type);
+			/*
+			 * TODO: check is OK to directly return
+			 * since mcu state machine should handle
+			 * state transition failed?
+			 */
+			mtk_tops_ser_cmd_clear();
+			return;
+		}
+
+		TOPS_INFO("SER type: %u successfully recovered\n", ser_params.type);
+
+		spin_lock_irqsave(&tops_ser.params_lock, flag);
+		/*
+		 * If there isn't queued any other SER cmd that has higher priority
+		 * than current SER command, clear SER command and exit.
+		 * Otherwise let the work perform reset again for high priority SER.
+		 */
+		if (tops_ser.ser_params.type > ser_params.type
+		    || !memcmp(&tops_ser.ser_params, &ser_params,
+			       sizeof(struct tops_ser_params)))
+			__mtk_tops_ser_cmd_clear();
+	}
+
+	spin_unlock_irqrestore(&tops_ser.params_lock, flag);
+}
+
+int mtk_tops_ser(struct tops_ser_params *ser_params)
+{
+	unsigned long flag;
+
+	if (!ser_params)
+		return -EINVAL;
+
+	spin_lock_irqsave(&tops_ser.params_lock, flag);
+
+	/* higher SER type should not override lower SER type */
+	if (tops_ser.ser_params.type != __TOPS_SER_TYPE_MAX
+	    && tops_ser.ser_params.type < ser_params->type)
+		goto unlock;
+
+	memcpy(&tops_ser.ser_params, ser_params, sizeof(*ser_params));
+
+	schedule_work(&tops_ser.work);
+
+unlock:
+	spin_unlock_irqrestore(&tops_ser.params_lock, flag);
+
+	return 0;
+}
+
+int mtk_tops_ser_init(struct platform_device *pdev)
+{
+	INIT_WORK(&tops_ser.work, mtk_tops_ser_work);
+
+	spin_lock_init(&tops_ser.params_lock);
+
+	tops_ser.ser_params.type = __TOPS_SER_TYPE_MAX;
+
+	return 0;
+}
+
+int mtk_tops_ser_deinit(struct platform_device *pdev)
+{
+	return 0;
+}