This series focuses on CoreSight path power management. The changes can be divided into four parts for review:
Patches 01~06: Refactor the CPU idle flow with moving common code into the CoreSight core layer. Patches 07~14: Add link control during CPU idle. Patches 15~16: Support the sink (TRBE) control during CPU idle. Patches 17~19: Move the CPU hotplug flow into the coresight core layer and simplify the code.
This series is rebased on the coresight-next branch and has been verified on Juno-r2 and FVP RevC.
--- Changes in v6: - Rebase on the latest coresight-next branch. - Always save and restore TRBE context during idle (Will). - Use get_cpu() / put_cpu() when set the per CPU source pointer. - Link to v5: https://lore.kernel.org/r/20251119-arm_coresight_path_power_management_impro...
Changes in v5: - Set the per-CPU source pointer on target CPU (Suzuki). - Reused existed enable/disable buffer functions in TRBE callbacks (James). - Refactored refcount for source devices in SysFS mode. - Released path in cpu-hotplug off flow to avoid memory leak. - Updated ETMv3 driver when move common code into core layer. - Rebased on the latest coresight-next branch. - Link to v4: https://lore.kernel.org/r/20251104-arm_coresight_path_power_management_impro...
Changes in v4: - Changed to store path pointer in coresight_device, this is easier for fetching path pointer based on source device (Mike). - Dropped changes in CTI driver. - Only disabled path for CPU hot-plugged off but not enable path for hot-plugged in. - Removed James' test tags for modified patches. - Link to v3: https://lore.kernel.org/r/20250915-arm_coresight_power_management_fix-v3-0-e...
Signed-off-by: Leo Yan leo.yan@arm.com
--- Leo Yan (18): coresight: sysfs: Validate CPU online status for per-CPU sources coresight: Set per-CPU source pointer coresight: Register CPU PM notifier in core layer coresight: etm4x: Hook CPU PM callbacks coresight: Add callback to determine if PM is needed coresight: etm4x: Remove redundant condition checks in save and restore coresight: syscfg: Use spinlock to protect active variables coresight: Introduce coresight_enable_source() helper coresight: Save active path for system tracers coresight: etm4x: Set active path on target CPU coresight: etm3x: Set active path on target CPU coresight: sysfs: Use source's path pointer for path control coresight: Add 'in_idle' argument to path coresight: Control path during CPU idle coresight: Add PM callbacks for sink device coresight: sysfs: Increment refcount only for system tracers coresight: Take hotplug lock in enable_source_store() for Sysfs mode coresight: Move CPU hotplug callbacks to core layer
Yabin Cui (1): coresight: trbe: Save and restore state across CPU low power state
drivers/hwtracing/coresight/coresight-catu.c | 1 + drivers/hwtracing/coresight/coresight-core.c | 273 ++++++++++++++++++++- drivers/hwtracing/coresight/coresight-ctcu-core.c | 1 + drivers/hwtracing/coresight/coresight-cti-core.c | 1 + drivers/hwtracing/coresight/coresight-dummy.c | 1 + drivers/hwtracing/coresight/coresight-etb10.c | 1 + drivers/hwtracing/coresight/coresight-etm-perf.c | 2 +- drivers/hwtracing/coresight/coresight-etm3x-core.c | 65 ++--- drivers/hwtracing/coresight/coresight-etm4x-core.c | 153 +++--------- drivers/hwtracing/coresight/coresight-funnel.c | 1 + drivers/hwtracing/coresight/coresight-priv.h | 3 + drivers/hwtracing/coresight/coresight-replicator.c | 1 + drivers/hwtracing/coresight/coresight-stm.c | 1 + drivers/hwtracing/coresight/coresight-syscfg.c | 22 +- drivers/hwtracing/coresight/coresight-syscfg.h | 2 + drivers/hwtracing/coresight/coresight-sysfs.c | 126 +++------- drivers/hwtracing/coresight/coresight-tmc-core.c | 1 + drivers/hwtracing/coresight/coresight-tnoc.c | 2 + drivers/hwtracing/coresight/coresight-tpda.c | 1 + drivers/hwtracing/coresight/coresight-tpdm.c | 1 + drivers/hwtracing/coresight/coresight-tpiu.c | 1 + drivers/hwtracing/coresight/coresight-trbe.c | 60 ++++- drivers/hwtracing/coresight/ultrasoc-smb.c | 1 + include/linux/coresight.h | 11 + 24 files changed, 458 insertions(+), 274 deletions(-) --- base-commit: 9c5ef7a30d9044f8706bd02bfdc4eff7266f3e25 change-id: 20251104-arm_coresight_path_power_management_improvement-dab4966f8280
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