On Fri, Mar 13, 2026 at 11:26:59AM +0000, Suzuki K Poulose wrote:
On 05/03/2026 10:17, Leo Yan wrote:
Add a callback in the source device that returns a boolean indicating whether power management operations are required. The save and restore flow is skipped if the callback returns false.
The ETMv4 driver implements its own version's callback.
Reviewed-by: James Clark james.clark@linaro.org Tested-by: James Clark james.clark@linaro.org Signed-off-by: Leo Yan leo.yan@arm.com
drivers/hwtracing/coresight/coresight-core.c | 9 ++++++++- drivers/hwtracing/coresight/coresight-etm4x-core.c | 16 ++++++++++++++++ include/linux/coresight.h | 1 + 3 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 5f7930ef537e2877649c404858d9fe6f593af037..6956429ca507d850c8b8c62c65de4b6fe1a1740c 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1681,7 +1681,14 @@ static bool coresight_pm_is_needed(struct coresight_device *csdev) !coresight_ops(csdev)->pm_restore_enable) return false;
- return true;
- /*
* PM callbacks are provided but pm_is_neended() is absent, it means* no extra check is needed.*/- if (!coresight_ops(csdev)->pm_is_needed)
return true;Do we really need this call back ? The ETM can skip registering the PM ops when it is not needed (make them NULL) ? And the oresight_get_mode() is any way available for all devices and use that simply in the core function ?
Good point! I will drop pm_is_needed() callback in new version.