coresight: tmc: making prepare/unprepare functions generic

Dealing with HW related matters in tmc_read_prepare/unprepare
becomes convoluted when many cases need to be handled distinctively.

As such moving processing related to HW setup to individual driver
files and keep the core driver generic.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/coresight-tmc-etf.c

@@ -71,7 +71,7 @@ static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
 	}
 }
 
-void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
+static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
@@ -202,3 +202,63 @@ const struct coresight_ops tmc_etf_cs_ops = {
 	.sink_ops	= &tmc_etf_sink_ops,
 	.link_ops	= &tmc_etf_link_ops,
 };
+
+int tmc_read_prepare_etb(struct tmc_drvdata *drvdata)
+{
+	enum tmc_mode mode;
+	int ret = 0;
+	unsigned long flags;
+
+	/* config types are set a boot time and never change */
+	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETB &&
+			 drvdata->config_type != TMC_CONFIG_TYPE_ETF))
+		return -EINVAL;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+
+	/* There is no point in reading a TMC in HW FIFO mode */
+	mode = readl_relaxed(drvdata->base + TMC_MODE);
+	if (mode != TMC_MODE_CIRCULAR_BUFFER) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	/* Disable the TMC if need be */
+	if (drvdata->enable)
+		tmc_etb_disable_hw(drvdata);
+
+	drvdata->reading = true;
+out:
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+	return ret;
+}
+
+int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
+{
+	enum tmc_mode mode;
+	unsigned long flags;
+
+	/* config types are set a boot time and never change */
+	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETB &&
+			 drvdata->config_type != TMC_CONFIG_TYPE_ETF))
+		return -EINVAL;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+
+	/* There is no point in reading a TMC in HW FIFO mode */
+	mode = readl_relaxed(drvdata->base + TMC_MODE);
+	if (mode != TMC_MODE_CIRCULAR_BUFFER) {
+		spin_unlock_irqrestore(&drvdata->spinlock, flags);
+		return -EINVAL;
+	}
+
+	/* Re-enable the TMC if need be */
+	if (drvdata->enable)
+		tmc_etb_enable_hw(drvdata);
+
+	drvdata->reading = false;
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+	return 0;
+}

drivers/hwtracing/coresight/coresight-tmc-etr.c

@@ -70,7 +70,7 @@ static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
 		drvdata->buf = drvdata->vaddr;
 }
 
-void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
+static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
@@ -126,3 +126,43 @@ static const struct coresight_ops_sink tmc_etr_sink_ops = {
 const struct coresight_ops tmc_etr_cs_ops = {
 	.sink_ops	= &tmc_etr_sink_ops,
 };
+
+int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
+{
+	unsigned long flags;
+
+	/* config types are set a boot time and never change */
+	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
+		return -EINVAL;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+
+	/* Disable the TMC if need be */
+	if (drvdata->enable)
+		tmc_etr_disable_hw(drvdata);
+
+	drvdata->reading = true;
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+	return 0;
+}
+
+int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
+{
+	unsigned long flags;
+
+	/* config types are set a boot time and never change */
+	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
+		return -EINVAL;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+
+	/* RE-enable the TMC if need be */
+	if (drvdata->enable)
+		tmc_etr_enable_hw(drvdata);
+
+	drvdata->reading = false;
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+	return 0;
+}

drivers/hwtracing/coresight/coresight-tmc.c

@@ -76,76 +76,43 @@ void tmc_disable_hw(struct tmc_drvdata *drvdata)
 static int tmc_read_prepare(struct tmc_drvdata *drvdata)
 {
 	int ret = 0;
-	unsigned long flags;
-	enum tmc_mode mode;
-
-	spin_lock_irqsave(&drvdata->spinlock, flags);
-	if (!drvdata->enable)
-		goto out;
 
 	switch (drvdata->config_type) {
 	case TMC_CONFIG_TYPE_ETB:
-		tmc_etb_disable_hw(drvdata);
-		break;
 	case TMC_CONFIG_TYPE_ETF:
-		/* There is no point in reading a TMC in HW FIFO mode */
-		mode = readl_relaxed(drvdata->base + TMC_MODE);
-		if (mode != TMC_MODE_CIRCULAR_BUFFER) {
-			ret = -EINVAL;
-			goto err;
-		}
-
-		tmc_etb_disable_hw(drvdata);
+		ret = tmc_read_prepare_etb(drvdata);
 		break;
 	case TMC_CONFIG_TYPE_ETR:
-		tmc_etr_disable_hw(drvdata);
+		ret = tmc_read_prepare_etr(drvdata);
 		break;
 	default:
 		ret = -EINVAL;
-		goto err;
 	}
 
-out:
-	drvdata->reading = true;
-	dev_info(drvdata->dev, "TMC read start\n");
-err:
-	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+	if (!ret)
+		dev_info(drvdata->dev, "TMC read start\n");
+
 	return ret;
 }
 
 static void tmc_read_unprepare(struct tmc_drvdata *drvdata)
 {
-	unsigned long flags;
-	enum tmc_mode mode;
-
-	spin_lock_irqsave(&drvdata->spinlock, flags);
-	if (!drvdata->enable)
-		goto out;
+	int ret = 0;
 
 	switch (drvdata->config_type) {
 	case TMC_CONFIG_TYPE_ETB:
-		tmc_etb_enable_hw(drvdata);
-		break;
 	case TMC_CONFIG_TYPE_ETF:
-		/* Make sure we don't re-enable a TMC in HW FIFO mode */
-		mode = readl_relaxed(drvdata->base + TMC_MODE);
-		if (mode != TMC_MODE_CIRCULAR_BUFFER)
-			goto err;
-
-		tmc_etb_enable_hw(drvdata);
+		ret = tmc_read_unprepare_etb(drvdata);
 		break;
 	case TMC_CONFIG_TYPE_ETR:
-		tmc_etr_disable_hw(drvdata);
+		ret = tmc_read_unprepare_etr(drvdata);
 		break;
 	default:
-		goto err;
+		ret = -EINVAL;
 	}
 
-out:
-	drvdata->reading = false;
-	dev_info(drvdata->dev, "TMC read end\n");
-err:
-	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+	if (!ret)
+		dev_info(drvdata->dev, "TMC read end\n");
 }
 
 static int tmc_open(struct inode *inode, struct file *file)

drivers/hwtracing/coresight/coresight-tmc.h

@@ -127,13 +127,13 @@ void tmc_enable_hw(struct tmc_drvdata *drvdata);
 void tmc_disable_hw(struct tmc_drvdata *drvdata);
 
 /* ETB/ETF functions */
-void tmc_etb_enable_hw(struct tmc_drvdata *drvdata);
-void tmc_etb_disable_hw(struct tmc_drvdata *drvdata);
+int tmc_read_prepare_etb(struct tmc_drvdata *drvdata);
+int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata);
 extern const struct coresight_ops tmc_etb_cs_ops;
 extern const struct coresight_ops tmc_etf_cs_ops;
 
 /* ETR functions */
-void tmc_etr_enable_hw(struct tmc_drvdata *drvdata);
-void tmc_etr_disable_hw(struct tmc_drvdata *drvdata);
+int tmc_read_prepare_etr(struct tmc_drvdata *drvdata);
+int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata);
 extern const struct coresight_ops tmc_etr_cs_ops;
 #endif