Add a "sinks" directory entry so that users can see all the sinks
available in the system in a single place. Individual sink are added
as they are registered with the coresight bus.
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
.../hwtracing/coresight/coresight-etm-perf.c | 76 +++++++++++++++++++
.../hwtracing/coresight/coresight-etm-perf.h | 6 +-
drivers/hwtracing/coresight/coresight.c | 18 +++++
include/linux/coresight.h | 7 +-
4 files changed, 104 insertions(+), 3 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index f21eb28b6782..c68a0036532c 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -14,6 +14,7 @@
#include <linux/perf_event.h>
#include <linux/percpu-defs.h>
#include <linux/slab.h>
+#include <linux/stringhash.h>
#include <linux/types.h>
#include <linux/workqueue.h>
@@ -43,8 +44,18 @@ static const struct attribute_group etm_pmu_format_group = {
.attrs = etm_config_formats_attr,
};
+static struct attribute *etm_config_sinks_attr[] = {
+ NULL,
+};
+
+static const struct attribute_group etm_pmu_sinks_group = {
+ .name = "sinks",
+ .attrs = etm_config_sinks_attr,
+};
+
static const struct attribute_group *etm_pmu_attr_groups[] = {
&etm_pmu_format_group,
+ &etm_pmu_sinks_group,
NULL,
};
@@ -479,6 +490,71 @@ int etm_perf_symlink(struct coresight_device *csdev, bool link)
return 0;
}
+static ssize_t etm_perf_sink_name_show(struct device *dev,
+ struct device_attribute *dattr,
+ char *buf)
+{
+ /* See function coresight_get_sink_by_id() to know where this is used */
+ u32 hash = hashlen_hash(hashlen_string(NULL, dattr->attr.name));
+
+ return scnprintf(buf, PAGE_SIZE, "%x\n", hash);
+}
+
+int etm_perf_add_symlink_sink(struct coresight_device *csdev)
+{
+ int ret;
+ struct device *pmu_dev = etm_pmu.dev;
+ struct device *pdev = csdev->dev.parent;
+ struct device_attribute *dattr;
+
+ if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
+ csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
+ return -EINVAL;
+
+ if (csdev->dattr != NULL)
+ return -EINVAL;
+
+ if (!etm_perf_up)
+ return -EPROBE_DEFER;
+
+ dattr = kzalloc(sizeof(*dattr), GFP_KERNEL);
+ dattr->attr.name = kstrdup(dev_name(pdev), GFP_KERNEL);.
+ dattr->attr.mode = 0444;
+ dattr->show = etm_perf_sink_name_show;
+ csdev->dattr = dattr;
+
+ ret = sysfs_add_file_to_group(&pmu_dev->kobj,
+ &dattr->attr, "sinks");
+
+ if (!ret)
+ return 0;
+
+ csdev->dattr = NULL;
+ kfree(dattr->attr.name);
+ kfree(dattr);
+
+ return ret;
+}
+
+void etm_perf_del_symlink_sink(struct coresight_device *csdev)
+{
+ struct device *pmu_dev = etm_pmu.dev;
+ struct device_attribute *dattr = csdev->dattr;
+
+ if (csdev->type != CORESIGHT_DEV_TYPE_SINK &&
+ csdev->type != CORESIGHT_DEV_TYPE_LINKSINK)
+ return;
+
+ if (!dattr)
+ return;
+
+ sysfs_remove_file_from_group(&pmu_dev->kobj,
+ &dattr->attr, "sinks");
+ csdev->dattr = NULL;
+ kfree(dattr->attr.name);
+ kfree(dattr);ext
+}
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 46c67a764877..a42fac83eac9 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -154,8 +154,9 @@ struct coresight_connection {
* @orphan: true if the component has connections that haven't been linked.
* @enable: 'true' if component is currently part of an active path.
* @activated: 'true' only if a _sink_ has been activated. A sink can be
- activated but not yet enabled. Enabling for a _sink_
- happens when a source has been selected for that it.
+ * activated but not yet enabled. Enabling for a _sink_
+ * appens when a source has been selected for that it.
+ * @dattr: Device attribute for sink representation under PMU directory.
*/
struct coresight_device {
struct coresight_connection *conns;
@@ -168,7 +169,9 @@ struct coresight_device {
atomic_t *refcnt;
bool orphan;
bool enable; /* true only if configured as part of a path */
+ /* sink specific fields */
bool activated; /* true only if a sink is part of a path */
+ struct device_attribute *dattr;