@@ -840,6 +840,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
 		idr_init(&drvdata->idr);
 		mutex_init(&drvdata->idr_mutex);
 		dev_list = &etr_devs;
+		INIT_LIST_HEAD(&drvdata->etr_buf_list);
 		break;
 	case TMC_CONFIG_TYPE_ETF:
 		desc.groups = coresight_etf_groups;

@@ -1919,6 +1919,100 @@ const struct coresight_ops tmc_etr_cs_ops = {
 	.panic_ops	= &tmc_etr_sync_ops,
 };
 
+/**
+ * tmc_clean_etr_buf_list - clean the etr_buf_list.
+ * @drvdata:	driver data of the TMC device.
+ *
+ * Remove the allocated node from the list and free the extra buffer.
+ */
+void tmc_clean_etr_buf_list(struct tmc_drvdata *drvdata)
+{
+	struct etr_buf_node *nd, *next;
+
+	list_for_each_entry_safe(nd, next, &drvdata->etr_buf_list, node) {
+		if (nd->sysfs_buf == drvdata->sysfs_buf) {
+			if (coresight_get_mode(drvdata->csdev) == CS_MODE_DISABLED) {
+				drvdata->sysfs_buf = NULL;
+				tmc_free_etr_buf(nd->sysfs_buf);
+				nd->sysfs_buf = NULL;
+			}
+			list_del(&nd->node);
+			kfree(nd);
+		} else {
+			/* Free allocated buffers which are not utilized by ETR */
+			list_del(&nd->node);
+			tmc_free_etr_buf(nd->sysfs_buf);
+			nd->sysfs_buf = NULL;
+			kfree(nd);
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(tmc_clean_etr_buf_list);
+
+/**
+ * tmc_create_etr_buf_list - create a list to manage the etr_buf_node.
+ * @drvdata:	driver data of the TMC device.
+ * @num_nodes:	number of nodes want to create with the list.
+ *
+ * Return 0 upon success and return the error number if fail.
+ */
+int tmc_create_etr_buf_list(struct tmc_drvdata *drvdata, int num_nodes)
+{
+	struct etr_buf_node *new_node;
+	struct etr_buf *sysfs_buf;
+	int i = 0, ret = 0;
+
+	/* We dont need a list if there is only one node */
+	if (num_nodes < 2)
+		return -EINVAL;
+
+	/* We expect that sysfs_buf in drvdata has already been allocated. */
+	if (drvdata->sysfs_buf) {
+		/* Directly insert the allocated sysfs_buf into the list first */
+		new_node = kzalloc(sizeof(struct etr_buf_node), GFP_KERNEL);
+		if (IS_ERR(new_node))
+			return PTR_ERR(new_node);
+
+		new_node->sysfs_buf = drvdata->sysfs_buf;
+		new_node->is_free = false;
+		list_add(&new_node->node, &drvdata->etr_buf_list);
+		i++;
+	}
+
+	while (i < num_nodes) {
+		new_node = kzalloc(sizeof(struct etr_buf_node), GFP_KERNEL);
+		if (IS_ERR(new_node)) {
+			ret = PTR_ERR(new_node);
+			break;
+		}
+
+		sysfs_buf = tmc_alloc_etr_buf(drvdata, drvdata->size, 0, cpu_to_node(0), NULL);
+		if (IS_ERR(sysfs_buf)) {
+			kfree(new_node);
+			ret = PTR_ERR(sysfs_buf);
+			break;
+		}
+
+		/* We dont have a available sysfs_buf in drvdata, setup one */
+		if (!drvdata->sysfs_buf) {
+			drvdata->sysfs_buf = sysfs_buf;
+			new_node->is_free = false;
+		} else
+			new_node->is_free = true;
+
+		new_node->sysfs_buf = sysfs_buf;
+		list_add(&new_node->node, &drvdata->etr_buf_list);
+		i++;
+	}
+
+	/* Clean the list if there is an error */
+	if (ret)
+		tmc_clean_etr_buf_list(drvdata);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(tmc_create_etr_buf_list);
+
 int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 {
 	int ret = 0;

@@ -208,6 +208,19 @@ struct tmc_resrv_buf {
 	s64		len;
 };
 
+/**
+ * @sysfs_buf:	Allocated sysfs_buf.
+ * @is_free:	Indicates whether the buffer is free to choose.
+ * @pos:	Position of the buffer.
+ * @node:	Node in etr_buf_list.
+ */
+struct etr_buf_node {
+	struct etr_buf		*sysfs_buf;
+	bool			is_free;
+	loff_t			pos;
+	struct list_head	node;
+};
+
 /**
  * struct tmc_drvdata - specifics associated to an TMC component
  * @atclk:	optional clock for the core parts of the TMC.

@@ -243,6 +256,8 @@ struct tmc_resrv_buf {
  *		(after crash) by default.
  * @crash_mdata: Reserved memory for storing tmc crash metadata.
  *		 Used by ETR/ETF.
+ * @etr_buf_list: List that is used to manage allocated etr_buf.
+ * @reading_node: Available buffer_node for byte-cntr reading.
  */
 struct tmc_drvdata {
 	struct clk		*atclk;

@@ -273,6 +288,8 @@ struct tmc_drvdata {
 	struct etr_buf		*perf_buf;
 	struct tmc_resrv_buf	resrv_buf;
 	struct tmc_resrv_buf	crash_mdata;
+	struct list_head        etr_buf_list;
+	struct etr_buf_node     *reading_node;
 };
 
 struct etr_buf_operations {

@@ -445,5 +462,7 @@ struct etr_buf *tmc_etr_get_buffer(struct coresight_device *csdev,
 				   enum cs_mode mode,
 				   struct coresight_path *path);
 extern const struct attribute_group coresight_etr_group;
+void tmc_clean_etr_buf_list(struct tmc_drvdata *drvdata);
+int tmc_create_etr_buf_list(struct tmc_drvdata *drvdata, int num_nodes);
 
 #endif