[PATCH] coresight: core: Add sysfs node to reset all sources and sinks
From: Mao Jinlong
Date: Wed Feb 08 2023 - 06:46:06 EST
Add sysfs node to reset all the sources and sinks. When mltiple
sources are enabled, write 1 to reset_source_sink node to disable
all sources and sinks.
Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx>
---
drivers/hwtracing/coresight/coresight-core.c | 106 +++++++++++++++++--
1 file changed, 99 insertions(+), 7 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index d3bf82c0de1d..06741ed2dee7 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -458,6 +458,28 @@ static bool coresight_disable_source(struct coresight_device *csdev)
return !csdev->enable;
}
+/**
+ * coresight_get_source - Get the source from the path
+ *
+ * @path: The list of devices.
+ *
+ * Returns the soruce csdev.
+ *
+ */
+static struct coresight_device *coresight_get_source(struct list_head *path)
+{
+ struct coresight_device *csdev;
+
+ if (!path)
+ return NULL;
+
+ csdev = list_first_entry(path, struct coresight_node, link)->csdev;
+ if (csdev->type != CORESIGHT_DEV_TYPE_SOURCE)
+ return NULL;
+
+ return csdev;
+}
+
/*
* coresight_disable_path_from : Disable components in the given path beyond
* @nd in the list. If @nd is NULL, all the components, except the SOURCE are
@@ -1159,20 +1181,18 @@ int coresight_enable(struct coresight_device *csdev)
}
EXPORT_SYMBOL_GPL(coresight_enable);
-void coresight_disable(struct coresight_device *csdev)
+static void _coresight_disable(struct coresight_device *csdev)
{
int cpu, ret;
struct list_head *path = NULL;
u32 hash;
- mutex_lock(&coresight_mutex);
-
ret = coresight_validate_source(csdev, __func__);
if (ret)
- goto out;
+ return;
if (!csdev->enable || !coresight_disable_source(csdev))
- goto out;
+ return;
switch (csdev->subtype.source_subtype) {
case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
@@ -1187,7 +1207,7 @@ void coresight_disable(struct coresight_device *csdev)
path = idr_find(&path_idr, hash);
if (path == NULL) {
pr_err("Path is not found for %s\n", dev_name(&csdev->dev));
- goto out;
+ return;
}
idr_remove(&path_idr, hash);
break;
@@ -1198,8 +1218,12 @@ void coresight_disable(struct coresight_device *csdev)
coresight_disable_path(path);
coresight_release_path(path);
+}
-out:
+void coresight_disable(struct coresight_device *csdev)
+{
+ mutex_lock(&coresight_mutex);
+ _coresight_disable(csdev);
mutex_unlock(&coresight_mutex);
}
EXPORT_SYMBOL_GPL(coresight_disable);
@@ -1761,8 +1785,76 @@ char *coresight_alloc_device_name(struct coresight_dev_list *dict,
}
EXPORT_SYMBOL_GPL(coresight_alloc_device_name);
+/*
+ * Set the sink active status to false.
+ */
+static int coresight_reset_sink(struct device *dev, void *data)
+{
+ struct coresight_device *csdev = to_coresight_device(dev);
+
+ if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
+ csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
+ csdev->activated)
+ csdev->activated = false;
+
+ return 0;
+}
+
+static void coresight_reset_all_sink(void)
+{
+ bus_for_each_dev(&coresight_bustype, NULL, NULL, coresight_reset_sink);
+}
+
+static ssize_t reset_source_sink_store(struct bus_type *bus,
+ const char *buf, size_t size)
+{
+ int id, cpu, ret = 0;
+ unsigned long val;
+ struct coresight_device *csdev;
+ struct list_head *path = NULL;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ mutex_lock(&coresight_mutex);
+
+ /* Disable all per cpu sources */
+ for_each_present_cpu(cpu) {
+ path = per_cpu(tracer_path, cpu);
+ if (path) {
+ csdev = coresight_get_source(path);
+ if (!csdev)
+ continue;
+ }
+ _coresight_disable(csdev);
+ }
+
+ /* Disable all sources which aren't associated with CPU */
+ idr_for_each_entry (&path_idr, path, id) {
+ csdev = coresight_get_source(path);
+ if (!csdev)
+ continue;
+
+ _coresight_disable(csdev);
+ }
+ /* Reset all activated sinks */
+ coresight_reset_all_sink();
+
+ mutex_unlock(&coresight_mutex);
+ return size;
+}
+static BUS_ATTR_WO(reset_source_sink);
+
+static struct attribute *coresight_reset_source_sink_attrs[] = {
+ &bus_attr_reset_source_sink.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(coresight_reset_source_sink);
+
struct bus_type coresight_bustype = {
.name = "coresight",
+ .bus_groups = coresight_reset_source_sink_groups,
};
static int __init coresight_init(void)
--
2.39.0