On 16/05/2025 5:07 pm, Leo Yan wrote:
This commit extends control over CoreSight components on an activated path during CPU PM.
An activated path is recorded in the 'path' field of coresight_device structure. The patch pointer is cleared when the path is disabled.
patch -> path
Traverses the links on the path to disable and re-enable components during CPU low-power modes.
Signed-off-by: Leo Yan leo.yan@arm.com
drivers/hwtracing/coresight/coresight-core.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 8f565bb3c535..075d485dcea5 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -596,6 +596,94 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode, goto out; } +static int coresight_save_path(struct coresight_path *path) +{> + u32 type;
- struct coresight_node *nd;
- struct coresight_device *source, *sink;
- if (!path)
return 0;- source = coresight_get_source(path);
- /*
* Do a sanity check as the source device must have been enabled when* run at here.*/- if (coresight_get_mode(source) == CS_MODE_DISABLED)
return -EINVAL;- sink = coresight_get_sink(path);
- /*
* Disable links. Deliberately to skip disabling the sink to avoid* latency.*/- nd = list_first_entry(&path->path_list, struct coresight_node, link);
- list_for_each_entry_continue(nd, &path->path_list, link) {
struct coresight_device *csdev, *parent, *child;csdev = nd->csdev;type = csdev->type;/* Adjust type for LINKSINK */if (type == CORESIGHT_DEV_TYPE_LINKSINK)type = (csdev == sink) ? CORESIGHT_DEV_TYPE_SINK :CORESIGHT_DEV_TYPE_LINK;
Not sure if we want to disable helper devices too?
if (type != CORESIGHT_DEV_TYPE_LINK)continue;parent = list_prev_entry(nd, link)->csdev;child = list_next_entry(nd, link)->csdev;coresight_disable_link(csdev, parent, child, source);- }
- return 0;
+}
+static void coresight_restore_path(struct coresight_path *path) +{
- int ret;
- u32 type;
- struct coresight_device *source, *sink;
- struct coresight_node *nd;
- if (!path)
return;- source = coresight_get_source(path);
- if (coresight_get_mode(source) == CS_MODE_DISABLED)
return;- sink = coresight_get_sink(path);
- list_for_each_entry_reverse(nd, &path->path_list, link) {
struct coresight_device *csdev, *parent, *child;csdev = nd->csdev;type = csdev->type;if (type == CORESIGHT_DEV_TYPE_LINKSINK)type = (csdev == sink) ? CORESIGHT_DEV_TYPE_SINK :CORESIGHT_DEV_TYPE_LINK;if (type != CORESIGHT_DEV_TYPE_LINK)continue;parent = list_prev_entry(nd, link)->csdev;child = list_next_entry(nd, link)->csdev;ret = coresight_enable_link(csdev, parent, child,coresight_get_source(path));if (ret) {dev_err(&csdev->dev, "Failed to restore\n");coresight_disable_path_from(path, nd);return;}- }
+}
- struct coresight_device *coresight_get_sink(struct coresight_path *path) { struct coresight_device *csdev;
@@ -1605,9 +1693,15 @@ static int coresight_cpu_pm_notify(struct notifier_block *nb, unsigned long cmd, case CPU_PM_ENTER: if (coresight_save_source(source)) return NOTIFY_BAD;
if (coresight_save_path(source->path)) {coresight_restore_source(source);return NOTIFY_BAD;}coresight_restore_path(source->path);