[PATCH v3 07/10] coresight: tmc: add prepare/unprepare functions for byte-cntr

@@ -229,7 +229,11 @@ static int tmc_prepare_crashdata(struct tmc_drvdata *drvdata)
 
 static int tmc_read_prepare(struct tmc_drvdata *drvdata)
 {
-	int ret = 0;
+	struct coresight_device *helper = coresight_get_helper(drvdata->csdev,
+						CORESIGHT_DEV_SUBTYPE_HELPER_CTCU);
+	struct ctcu_byte_cntr *byte_cntr_data = NULL;
+	struct ctcu_drvdata *ctcu_drvdata = NULL;
+	int port, ret = 0;
 
 	switch (drvdata->config_type) {
 	case TMC_CONFIG_TYPE_ETB:

@@ -237,7 +241,18 @@ static int tmc_read_prepare(struct tmc_drvdata *drvdata)
 		ret = tmc_read_prepare_etb(drvdata);
 		break;
 	case TMC_CONFIG_TYPE_ETR:
-		ret = tmc_read_prepare_etr(drvdata);
+		if (helper) {
+			port = coresight_get_port_helper(drvdata->csdev, helper);
+			if (port >= 0) {
+				ctcu_drvdata = dev_get_drvdata(helper->dev.parent);
+				byte_cntr_data = &ctcu_drvdata->byte_cntr_data[port];
+			}
+		}
+
+		if (byte_cntr_data && byte_cntr_data->thresh_val)
+			ret = tmc_read_prepare_byte_cntr(drvdata, byte_cntr_data);
+		else
+			ret = tmc_read_prepare_etr(drvdata);
 		break;
 	default:
 		ret = -EINVAL;

@@ -251,7 +266,11 @@ static int tmc_read_prepare(struct tmc_drvdata *drvdata)
 
 static int tmc_read_unprepare(struct tmc_drvdata *drvdata)
 {
-	int ret = 0;
+	struct coresight_device *helper = coresight_get_helper(drvdata->csdev,
+						CORESIGHT_DEV_SUBTYPE_HELPER_CTCU);
+	struct ctcu_byte_cntr *byte_cntr_data = NULL;
+	struct ctcu_drvdata *ctcu_drvdata = NULL;
+	int port, ret = 0;
 
 	switch (drvdata->config_type) {
 	case TMC_CONFIG_TYPE_ETB:

@@ -259,7 +278,18 @@ static int tmc_read_unprepare(struct tmc_drvdata *drvdata)
 		ret = tmc_read_unprepare_etb(drvdata);
 		break;
 	case TMC_CONFIG_TYPE_ETR:
-		ret = tmc_read_unprepare_etr(drvdata);
+		if (helper) {
+			port = coresight_get_port_helper(drvdata->csdev, helper);
+			if (port >= 0) {
+				ctcu_drvdata = dev_get_drvdata(helper->dev.parent);
+				byte_cntr_data = &ctcu_drvdata->byte_cntr_data[port];
+			}
+		}
+
+		if (byte_cntr_data && byte_cntr_data->thresh_val)
+			ret = tmc_read_unprepare_byte_cntr(drvdata, byte_cntr_data);
+		else
+			ret = tmc_read_unprepare_etr(drvdata);
 		break;
 	default:
 		ret = -EINVAL;

@@ -2032,6 +2032,85 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 	return 0;
 }
 
+int tmc_read_prepare_byte_cntr(struct tmc_drvdata *drvdata,
+			       struct ctcu_byte_cntr *byte_cntr_data)
+{
+	unsigned long flags;
+	int ret = 0;
+
+	/* config types are set a boot time and never change */
+	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
+		return -EINVAL;
+
+	if (coresight_get_mode(drvdata->csdev) != CS_MODE_SYSFS)
+		return -EINVAL;
+
+	/*
+	 * The threshold value must not exceed the buffer size.
+	 * A margin should be maintained between the two values to account
+	 * for the time gap between the interrupt and buffer switching.
+	 */
+	if (byte_cntr_data->thresh_val + SZ_16K >= drvdata->size) {
+		dev_err(&drvdata->csdev->dev, "The threshold value is too large\n");
+		return -EINVAL;
+	}
+
+	raw_spin_lock_irqsave(&drvdata->spinlock, flags);
+	if (byte_cntr_data->reading) {
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+
+	byte_cntr_data->reading = true;
+	raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
+	/* Insert current sysfs_buf into the list */
+	ret = tmc_create_etr_buf_node(drvdata, drvdata->sysfs_buf);
+	if (!ret) {
+		/*
+		 * Add one more sysfs_buf for byte-cntr function, byte-cntr always reads
+		 * the data from the buffer which has been synced. Switch the buffer when
+		 * the used buffer is nearly full. The used buffer will be synced and made
+		 * available for reading before switch.
+		 */
+		ret = tmc_create_etr_buf_node(drvdata, NULL);
+		if (ret) {
+			dev_err(&drvdata->csdev->dev, "Failed to create etr_buf_node\n");
+			tmc_delete_etr_buf_node(drvdata);
+			byte_cntr_data->reading = false;
+			goto out;
+		}
+	}
+
+	raw_spin_lock_irqsave(&drvdata->spinlock, flags);
+	atomic_set(&byte_cntr_data->irq_cnt, 0);
+	enable_irq(byte_cntr_data->byte_cntr_irq);
+	enable_irq_wake(byte_cntr_data->byte_cntr_irq);
+	byte_cntr_data->total_size = 0;
+	byte_cntr_data->irq_num = 0;
+
+out_unlock:
+	raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+out:
+	return ret;
+}
+
+int tmc_read_unprepare_byte_cntr(struct tmc_drvdata *drvdata,
+				 struct ctcu_byte_cntr *byte_cntr_data)
+{
+	struct device *dev = &drvdata->csdev->dev;
+
+	guard(raw_spinlock_irqsave)(&byte_cntr_data->spin_lock);
+	disable_irq_wake(byte_cntr_data->byte_cntr_irq);
+	disable_irq(byte_cntr_data->byte_cntr_irq);
+	byte_cntr_data->reading = false;
+	tmc_delete_etr_buf_node(drvdata);
+	dev_dbg(dev, "send data total size:%llu bytes, irq_cnt:%d\n",
+		byte_cntr_data->total_size, byte_cntr_data->irq_num);
+
+	return 0;
+}
+
 static const char *const buf_modes_str[] = {
 	[ETR_MODE_FLAT]		= "flat",
 	[ETR_MODE_ETR_SG]	= "tmc-sg",

@@ -14,6 +14,8 @@
 #include <linux/refcount.h>
 #include <linux/crc32.h>
 
+#include "coresight-ctcu.h"
+
 #define TMC_RSZ			0x004
 #define TMC_STS			0x00c
 #define TMC_RRD			0x010

@@ -357,6 +359,12 @@ extern const struct coresight_ops tmc_etr_cs_ops;
 ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata,
 				loff_t pos, size_t len, char **bufpp);
 
+/* Byte-cntr functions */
+int tmc_read_prepare_byte_cntr(struct tmc_drvdata *drvdata,
+			       struct ctcu_byte_cntr *byte_cntr_data);
+int tmc_read_unprepare_byte_cntr(struct tmc_drvdata *drvdata,
+				 struct ctcu_byte_cntr *byte_cntr_data);
+
 
 #define TMC_REG_PAIR(name, lo_off, hi_off)				\
 static inline u64							\