[PATCH v8 16/23] coresight: etm3x: Set active path on target CPU

[Leo Yan]

Set and clear the path pointer on the target CPU during ETM enable
and disable operations.

Tested-by: James Clark <james.clark at linaro.org>
Reviewed-by: Yeoreum Yun <yeoreum.yun at arm.com>
Reviewed-by: James Clark <james.clark at linaro.org>
Signed-off-by: Leo Yan <leo.yan at arm.com>
---
 drivers/hwtracing/coresight/coresight-etm3x-core.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm3x-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
index ab47f69e923fb191b48b82367dce465c79b3a93d..c2b8c096cbe9e9759b3d17f019a2d73f59234ac9 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -441,6 +441,7 @@ static int etm_enable_hw(struct etm_drvdata *drvdata)
 
 struct etm_enable_arg {
 	struct etm_drvdata *drvdata;
+	struct coresight_path *path;
 	int rc;
 };
 
@@ -462,8 +463,12 @@ static void etm_enable_sysfs_smp_call(void *info)
 	arg->rc = etm_enable_hw(arg->drvdata);
 
 	/* The tracer didn't start */
-	if (arg->rc)
+	if (arg->rc) {
 		coresight_set_mode(csdev, CS_MODE_DISABLED);
+		return;
+	}
+
+	csdev->path = arg->path;
 }
 
 void etm_release_trace_id(struct etm_drvdata *drvdata)
@@ -492,10 +497,13 @@ static int etm_enable_perf(struct coresight_device *csdev,
 	ret = etm_enable_hw(drvdata);
 
 	/* Failed to start tracer; roll back to DISABLED mode */
-	if (ret)
+	if (ret) {
 		coresight_set_mode(csdev, CS_MODE_DISABLED);
+		return ret;
+	}
 
-	return ret;
+	csdev->path = path;
+	return 0;
 }
 
 static int etm_enable_sysfs(struct coresight_device *csdev, struct coresight_path *path)
@@ -514,6 +522,7 @@ static int etm_enable_sysfs(struct coresight_device *csdev, struct coresight_pat
 	 */
 	if (cpu_online(drvdata->cpu)) {
 		arg.drvdata = drvdata;
+		arg.path = path;
 		ret = smp_call_function_single(drvdata->cpu,
 					       etm_enable_sysfs_smp_call, &arg, 1);
 		if (!ret)
@@ -583,6 +592,7 @@ static void etm_disable_sysfs_smp_call(void *info)
 
 	etm_disable_hw(drvdata);
 
+	drvdata->csdev->path = NULL;
 	coresight_set_mode(drvdata->csdev, CS_MODE_DISABLED);
 }
 
@@ -607,6 +617,7 @@ static void etm_disable_perf(struct coresight_device *csdev)
 
 	CS_LOCK(drvdata->csa.base);
 
+	drvdata->csdev->path = NULL;
 	coresight_set_mode(drvdata->csdev, CS_MODE_DISABLED);
 
 	/*

-- 
2.34.1