@@ -8,6 +8,7 @@
#include <linux/types.h>
#include <linux/device.h>
#include <linux/io.h>
+#include <linux/idr.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>
@@ -27,6 +28,13 @@
static DEFINE_MUTEX(coresight_mutex);
static DEFINE_PER_CPU(struct coresight_device *, csdev_sink);
+/*
+ * Use IDR to map the hash of the source's device name
+ * to the pointer of path for the source. The idr is for
+ * the sources which aren't associated with CPU.
+ */
+static DEFINE_IDR(path_idr);
+
/**
* struct coresight_node - elements of a path, from source to sink
* @csdev: Address of an element.
@@ -43,14 +51,6 @@ struct coresight_node {
*/
static DEFINE_PER_CPU(struct list_head *, tracer_path);
-/*
- * As of this writing only a single STM can be found in CS topologies. Since
- * there is no way to know if we'll ever see more and what kind of
- * configuration they will enact, for the time being only define a single path
- * for STM.
- */
-static struct list_head *stm_path;
-
/*
* When losing synchronisation a new barrier packet needs to be inserted at the
* beginning of the data collected in a buffer. That way the decoder knows that
@@ -1076,6 +1076,7 @@ int coresight_enable(struct coresight_device *csdev)
struct coresight_device *sink;
struct list_head *path;
enum coresight_dev_subtype_source subtype;
+ u32 hash;
subtype = csdev->subtype.source_subtype;
@@ -1130,7 +1131,14 @@ int coresight_enable(struct coresight_device *csdev)
per_cpu(tracer_path, cpu) = path;
break;
case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
- stm_path = path;
+ /*
+ * Use the hash of source's device name as ID
+ * and map the ID to the pointer of the path.
+ */
+ hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
+ ret = idr_alloc_u32(&path_idr, path, &hash, hash, GFP_KERNEL);
+ if (ret)
+ goto err_source;
break;
default:
/* We can't be here */
@@ -1154,6 +1162,7 @@ void coresight_disable(struct coresight_device *csdev)
{
int cpu, ret;
struct list_head *path = NULL;
+ u32 hash;
mutex_lock(&coresight_mutex);
@@ -1171,14 +1180,20 @@ void coresight_disable(struct coresight_device *csdev)
per_cpu(tracer_path, cpu) = NULL;
break;
case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
- path = stm_path;
- stm_path = NULL;
+ hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
+ /* Find the path by the hash. */
+ path = idr_find(&path_idr, hash);
+ if (path == NULL) {
+ pr_err("Path is not found for %s\n", dev_name(&csdev->dev));
+ goto out;
+ }
break;
default:
/* We can't be here */
break;
}
+ idr_remove(&path_idr, hash);
coresight_disable_path(path);
coresight_release_path(path);