This series fixes and improves clock usage in the Arm CoreSight drivers.
Based on the DT binding documents, the trace clock (atclk) is defined in some CoreSight modules, but support is absent. In most cases, the issue is hidden because the atclk clock is shared by multiple CoreSight modules and the clock is enabled anyway by other drivers. The first three patches address this issue.
The programming clock (pclk) management in CoreSight drivers does not use the devm_XXX() variant APIs, the drivers needs to manually disable and release clocks for errors and for normal module exit. However, the drivers miss to disable clocks during module exit. The atclk may also not be disabled in CoreSight drivers during module exit. By using devm APIs, patches 04 and 05 fix clock disabling issues.
Another issue is pclk might be enabled twice in init phase - once by AMBA bus driver, and again by CoreSight drivers. This is fixed in patch 06.
Patches 07 to 10 refactor the clock related code. Patch 07 consolidates the clock initialization into a central place. Patch 08 polishes driver data allocation. Patch 09 makes the clock enabling sequence consistent. Patch 09 removes redundant condition checks and adds error handling in runtime PM.
This series has been verified on Arm64 Juno platform, for both DT and ACPI modes.
Also tested on Hikey960 for emulating static funnel and replicator without clock nodes. Mark kindly tested on imx8mp board.
--- Changes in v6: - Changed to devm_clk_get_optional_enabled() for pclk, for fixing the clock initialization failure reported by Mark. - Added James test tags as no change for ACPI. - Link to v5: https://lore.kernel.org/r/20250724-arm_cs_fix_clock_v4-v5-0-63f648dae021@arm...
Changes in v5: - Skip clock management for ACPI devices (Suzuki). - Link to v4: https://lore.kernel.org/r/20250627-arm_cs_fix_clock_v4-v4-0-0ce0009c38f8@arm...
Changes in v4: - Separated patch 07 into two patches, one is for clock consolidation and another is for polishing driver data allocation (Anshuman).
Changes in v3: - Updated subjects for patches 04 and 05 (Anshuman). - Refined condition checking "if (dev_is_amba(dev))" in patch 07 (Anshuman).
--- Leo Yan (10): coresight: tmc: Support atclk coresight: catu: Support atclk coresight: etm4x: Support atclk coresight: Appropriately disable programming clocks coresight: Appropriately disable trace bus clocks coresight: Avoid enable programming clock duplicately coresight: Consolidate clock enabling coresight: Refactor driver data allocation coresight: Make clock sequence consistent coresight: Refactor runtime PM
drivers/hwtracing/coresight/coresight-catu.c | 53 ++++++++--------- drivers/hwtracing/coresight/coresight-catu.h | 1 + drivers/hwtracing/coresight/coresight-core.c | 48 ++++++++++++++++ drivers/hwtracing/coresight/coresight-cpu-debug.c | 41 +++++--------- drivers/hwtracing/coresight/coresight-ctcu-core.c | 24 +++----- drivers/hwtracing/coresight/coresight-etb10.c | 18 ++---- drivers/hwtracing/coresight/coresight-etm3x-core.c | 17 ++---- drivers/hwtracing/coresight/coresight-etm4x-core.c | 32 ++++++----- drivers/hwtracing/coresight/coresight-etm4x.h | 4 +- drivers/hwtracing/coresight/coresight-funnel.c | 66 ++++++++-------------- drivers/hwtracing/coresight/coresight-replicator.c | 63 ++++++++------------- drivers/hwtracing/coresight/coresight-stm.c | 34 +++++------ drivers/hwtracing/coresight/coresight-tmc-core.c | 48 ++++++++-------- drivers/hwtracing/coresight/coresight-tmc.h | 2 + drivers/hwtracing/coresight/coresight-tpiu.c | 36 +++++------- include/linux/coresight.h | 31 +--------- 16 files changed, 228 insertions(+), 290 deletions(-) --- base-commit: a80198ba650f50d266d7fc4a6c5262df9970f9f2 change-id: 20250627-arm_cs_fix_clock_v4-e24b1e1f8920
Best regards,