CoreSight July 2025

coresight@lists.linaro.org

9 participants
47 discussions

[PATCH v1 0/5] coresight: Fix device registration and unregistration

by Leo Yan

This series is to fix device registration and unregistration. The first patch addresses the resource is not released properly for a failure case during a device registration. The second patch is to use mutex to protect unregistration flow. The last three patches are for refactoring. Patch 03 explicitly uses the parent device handler. Patch 04 separates the success and failure flows for code readable and easier maintenance. Patch 05 improves the error handling by invoking specific functions for resource cleanup. Leo Yan (5): coresight: Correct sink ID map allocation failure handling coresight: Protect unregistration with mutex coresight: Explicitly use the parent device handler coresight: Separate failure and success flows coresight: Refine error handling for device registration drivers/hwtracing/coresight/coresight-core.c | 67 +++++++++++--------- 1 file changed, 37 insertions(+), 30 deletions(-) -- 2.34.1

1 week, 4 days

[PATCH v6 00/10] coresight: Fix and improve clock usage

by Leo Yan

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@ar… 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@ar… 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, -- Leo Yan <leo.yan(a)arm.com>

2 weeks, 3 days

[PATCH v2 00/28] CoreSight: Address CPU Power Management Issues

by Leo Yan

This series addresses CPU power management issues in the CoreSight drivers. For easier review, the patches are organized into two categories: o Patches 01 ~ 10 focus on CPU power management within the ETM drivers. These patches fix SMP-safe access to the mode, correct context synchronization, and refactor the CPU suspend/resume flows. o Patches 11 ~ 28 extend CPU power management to cover activated paths, including helpers, links, and sinks. These changes move CPU PM and hotplug notifiers from the ETMv4 driver into the CoreSight core layer. Summary of Changes: - Patches 01 ~ 03: Fix device mode access in the SMP mode. - Patch 04 : A minor fix for polling bit. - Patches 05 ~ 07: Improve the context synchronization based on the ETM specification (IHI0064H.b) and Arm ARM (ARM DDI 0487 L.a). - Patches 08 ~ 10: Refactor the context save/restore flow in the ETMv4 driver, in the end, the CPU PM callbacks reuse the normal enabling and disabling flows. - Patches 11 ~ 17: Move CPU PM code from ETMv4 driver to the core layer. - Patches 18 ~ 25: Enhance device mode handling in the CTI driver, distinguishes debug mode from trace modes (Perf or SysFS mode). Extend support activated paths during CPU idle. Support save and restore context for per-CPU sink (TRBE). - Patches 26 ~ 28: Move CPU hotplug notifier from the ETMv4 driver to the core layer. The full path is now managed in CPU hotplug. Verification: This series has been verified on the following platforms: - Hikey960, Juno-r0 and Juno-r2: Note that the firmware on Hikey960 and Juno-r0 is unstable. While no CoreSight failures were observed, but the CPU hotplug or CPU idle itself may fail intermittently. Juno-r2 is much stable and can pass 24+ hours stress test. - FVP RevC: Verified TRBE changes. Stress test script: #!/usr/bin/bash echo 1 > /sys/bus/coresight/devices/tmc_etr0/enable_sink while true; do echo 0 > /sys/devices/system/cpu/cpu2/online; echo 1 > /sys/devices/system/cpu/cpu2/online; done & while true; do echo 1 > /sys/bus/coresight/devices/etm2/enable_source; echo 0 > /sys/bus/coresight/devices/etm2/enable_source; done & --- Changes in v2: - Refactored ETMv4 suspend and resume for reusing the normal enabling and disabling flows (James). - Used a per-CPU structure to maintain path pointers (James). - Supported helpers in CPU PM flows (James). - Fixed the SMP-safe access to device mode. - Fixed the context synchronization in ETMv4x driver. - Link to v1: https://lore.kernel.org/linux-arm-kernel/20250516160742.1200904-1-leo.yan@a… Signed-off-by: Leo Yan <leo.yan(a)arm.com> --- Leo Yan (27): coresight: Change device mode to atomic type coresight: etm4x: Always set tracer's device mode on target CPU coresight: etm3x: Always set tracer's device mode on target CPU coresight: etm4x: Correct polling IDLE bit coresight: etm4x: Ensure context synchronization is not ignored coresight: etm4x: Add context synchronization before enabling trace coresight: etm4x: Properly control filter in CPU idle with FEAT_TRF coresight: etm4x: Remove the state_needs_restore flag coresight: etm4x: Add flag to control single-shot restart coresight: etm4x: Reuse normal enable and disable logic in CPU idle coresight: Populate CPU ID into the coresight_device structure 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 context save/restore is needed coresight: etm4x: Remove redundant condition checks in save and restore coresight: cti: Fix race condition by using device mode coresight: cti: Introduce CS_MODE_DEBUG mode coresight: cti: Properly handle modes in CPU PM notifiers coresight: Add per-CPU path pointer coresight: Add 'in_idle' argument to path enable/disable functions coresight: Control path during CPU idle coresight: Add PM callbacks for percpu sink coresight: Take hotplug lock in enable_source_store() for Sysfs mode coresight: Move CPU hotplug callbacks to core layer coresight: Manage activated path during CPU hotplug 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 | 337 ++++++++++++-- drivers/hwtracing/coresight/coresight-ctcu-core.c | 1 + drivers/hwtracing/coresight/coresight-cti-core.c | 40 +- drivers/hwtracing/coresight/coresight-cti-sysfs.c | 2 +- drivers/hwtracing/coresight/coresight-dummy.c | 1 + drivers/hwtracing/coresight/coresight-etb10.c | 1 + drivers/hwtracing/coresight/coresight-etm3x-core.c | 61 ++- drivers/hwtracing/coresight/coresight-etm4x-core.c | 488 ++++++--------------- drivers/hwtracing/coresight/coresight-etm4x.h | 62 --- drivers/hwtracing/coresight/coresight-funnel.c | 1 + drivers/hwtracing/coresight/coresight-replicator.c | 1 + drivers/hwtracing/coresight/coresight-stm.c | 1 + drivers/hwtracing/coresight/coresight-sysfs.c | 10 + drivers/hwtracing/coresight/coresight-tmc-core.c | 1 + 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 | 85 ++++ drivers/hwtracing/coresight/ultrasoc-smb.c | 1 + include/linux/coresight.h | 55 ++- 21 files changed, 665 insertions(+), 487 deletions(-) --- base-commit: 66701750d5565c574af42bef0b789ce0203e3071 change-id: 20250611-arm_cs_pm_fix_v3-f4ae29bb7d81 Best regards, -- Leo Yan <leo.yan(a)arm.com>

2 weeks, 4 days

[PATCH v9 0/2] coresight: Add label sysfs node support

by Mao Jinlong

Change since V8: 1. Add label in all documentations of coresight components. 2. Add control of the visibility of the label sysfs attribute. V8 link: https://lkml.org/lkml/2025/7/3/985 Change since V7: 1. Update the conflict when apply to coresight next. 2. Update the Date and version in ABI file. V7 link: https://patchwork.kernel.org/project/linux-arm-kernel/patch/20250226121926.… Change since V6: 1. Update the date and verison in ABI file. Change since V5: 1. Update the kernel version of ABI files. 2. Add link of different patch versions. V5 link: https://patchwork.kernel.org/project/linux-arm-msm/cover/20241210122253.319… Change since V4: 1. Add label in DT and add label sysfs node for each coresight device. V4 link: https://patchwork.kernel.org/project/linux-arm-msm/cover/20240703122340.268… Change since V3: 1. Change device-name to arm,cs-dev-name. 2. Add arm,cs-dev-name to only CTI and sources' dt-binding. V3 link: https://patchwork.kernel.org/project/linux-arm-msm/cover/20240131082628.628… Change since V2: 1. Fix the error in coresight core. drivers/hwtracing/coresight/coresight-core.c:1775:7: error: assigning to 'char *' from 'const char *' discards qualifiers 2. Fix the warning when run dtbinding check. Documentation/devicetree/bindings/arm/arm,coresight-cpu-debug.yaml: device-name: missing type definition V2 link: https://patchwork.kernel.org/project/linux-arm-msm/cover/20240115164252.265… Change since V1: 1. Change coresight-name to device name. 2. Add the device-name in coresight dt bindings. V1 link: https://patchwork.kernel.org/project/linux-arm-kernel/patch/20230208110716.… Mao Jinlong (2): dt-bindings: arm: Add label in the coresight components coresight: Add label sysfs node support .../testing/sysfs-bus-coresight-devices-cti | 6 ++ .../sysfs-bus-coresight-devices-dummy-source | 6 ++ .../testing/sysfs-bus-coresight-devices-etb10 | 6 ++ .../testing/sysfs-bus-coresight-devices-etm3x | 6 ++ .../testing/sysfs-bus-coresight-devices-etm4x | 6 ++ .../sysfs-bus-coresight-devices-funnel | 6 ++ .../testing/sysfs-bus-coresight-devices-stm | 6 ++ .../testing/sysfs-bus-coresight-devices-tmc | 6 ++ .../testing/sysfs-bus-coresight-devices-tpdm | 6 ++ .../testing/sysfs-bus-coresight-devices-trbe | 6 ++ .../bindings/arm/arm,coresight-cti.yaml | 4 ++ .../arm/arm,coresight-dummy-sink.yaml | 4 ++ .../arm/arm,coresight-dummy-source.yaml | 4 ++ .../arm/arm,coresight-dynamic-funnel.yaml | 4 ++ .../arm/arm,coresight-dynamic-replicator.yaml | 4 ++ .../bindings/arm/arm,coresight-etb10.yaml | 4 ++ .../bindings/arm/arm,coresight-etm.yaml | 4 ++ .../arm/arm,coresight-static-funnel.yaml | 4 ++ .../arm/arm,coresight-static-replicator.yaml | 4 ++ .../bindings/arm/arm,coresight-tmc.yaml | 4 ++ .../bindings/arm/arm,coresight-tpiu.yaml | 4 ++ .../bindings/arm/qcom,coresight-ctcu.yaml | 4 ++ .../arm/qcom,coresight-remote-etm.yaml | 4 ++ .../bindings/arm/qcom,coresight-tpda.yaml | 4 ++ .../bindings/arm/qcom,coresight-tpdm.yaml | 4 ++ drivers/hwtracing/coresight/coresight-sysfs.c | 71 ++++++++++++++++++- 26 files changed, 189 insertions(+), 2 deletions(-) -- 2.25.1

1 month, 2 weeks

[PATCH v3 0/2] Add Qualcomm extended CTI support

by Mao Jinlong

The QCOM extended CTI is a heavily parameterized version of ARM’s CSCTI. It allows a debugger to send to trigger events to a processor or to send a trigger event to one or more processors when a trigger event occurs on another processor on the same SoC, or even between SoCs. QCOM extended CTI supports up to 128 triggers. And some of the register offsets are changed. The commands to configure CTI triggers are the same as ARM's CTI. Changes in v3: 1. Rename is_extended_cti() to of_is_extended_cti(). 2. Add the missing 'i' when write the CTI trigger registers. 3. Convert the multi-line output in sysfs to single line. 4. Initialize offset arrays using designated initializer. Link to V2 - https://lore.kernel.org/all/20250429071841.1158315-3-quic_jinlmao@quicinc.c… Changes in V2: 1. Add enum for compatible items. 2. Move offset arrays to coresight-cti-core Yingchao Deng (2): dt-bindings: arm: Add Qualcomm extended CTI coresight: cti: Add Qualcomm extended CTI support .../bindings/arm/arm,coresight-cti.yaml | 4 +- .../hwtracing/coresight/coresight-cti-core.c | 127 +++++++++++++---- .../coresight/coresight-cti-platform.c | 16 ++- .../hwtracing/coresight/coresight-cti-sysfs.c | 128 ++++++++++++++---- drivers/hwtracing/coresight/coresight-cti.h | 75 +++++----- 5 files changed, 248 insertions(+), 102 deletions(-) -- 2.25.1

1 month, 2 weeks

Re: [PATCH v5 04/10] coresight: Appropriately disable programming clocks

by Leo Yan

On Wed, Jul 30, 2025 at 12:09:42PM +0100, Mark Brown wrote: > On Wed, Jul 30, 2025 at 12:01:25PM +0100, Suzuki K Poulose wrote: > > > I would recommend using that and don't force the use of apb_clk/apb > > for AMBA devices. If the firmware doesn't specify a clock, but does > > specify the CoreSight components, it knows it better. > > And perhaps more to the point if a currently working system suddenly > starts requiring additional clocks in it's binding that's an ABI break. Yes, the change should not break any platforms if the DT binding is passed correctly. I will update with devm_clk_get_optional_enabled(). Just for the record, I was a bit concerned that the driver might not report a missing clock after switching to the optional clock API. After discussed with Rob and Suzuki, I understand this should not be a problem. Any missing clock issue can be caught by the DT schema static checker, or a system hang during the development phase would remind developers to bind clocks properly. Thanks, Leo

1 month, 3 weeks

Re: [PATCH v5 04/10] coresight: Appropriately disable programming clocks

by Suzuki K Poulose

On 29/07/2025 12:31, Mark Brown wrote: > On Mon, Jul 28, 2025 at 05:45:04PM +0100, Mark Brown wrote: >> On Thu, Jul 24, 2025 at 04:22:34PM +0100, Leo Yan wrote: >> >> Previously we would return NULL for any error (which isn't super great >> for deferred probe but never mind). >> >>> + pclk = devm_clk_get_enabled(dev, "apb_pclk"); >>> + if (IS_ERR(pclk)) >>> + pclk = devm_clk_get_enabled(dev, "apb"); >> >> ... >> >>> return pclk; >>> } >> >> Now we pass errors back to the caller, making missing clocks fatal. > > Thinking about this some more I think for compatiblity these clocks need > to be treated as optional - that's what the original code was > effectively doing, and I can imagine this isn't the only SoC which has > (hopefully) always on clocks and didn't wire things up in DT. You're right. The static components (funnels, replicators) don't have APB programming interface and hence no clocks. That said, may be the "is amba device" check could be used to enforce the presence of a clock. I will let Leo sort this out Suzuki

1 month, 3 weeks

[PATCH v5 00/10] coresight: Fix and improve clock usage

by Leo Yan

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. --- 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@ar… 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, -- Leo Yan <leo.yan(a)arm.com>

1 month, 3 weeks

Re: [PATCH v6 0/7] Provides support for Trigger Generation Unit

by Mike Leach

Hi, On Wed, 23 Jul 2025 at 07:33, Songwei Chai <quic_songchai(a)quicinc.com> wrote: > > > On 7/21/2025 9:39 PM, Mike Leach wrote: > > Hi, > > On Wed, 9 Jul 2025 at 11:41, songchai <songchai(a)qti.qualcomm.com> wrote: > > From: Songwei Chai <quic_songchai(a)quicinc.com> > > Provide support for the TGU (Trigger Generation Unit), which can be > utilized to sense a plurality of signals and create a trigger into > the CTI or generate interrupts to processors once the input signal > meets the conditions. We can treat the TGU’s workflow as a flowsheet, > it has some “steps” regions for customization. In each step region, > we can set the signals that we want with priority in priority_group, set > the conditions in each step via condition_decode, and set the resultant > action by condition_select. Meanwhile, some TGUs (not all) also provide > timer/counter functionality. Based on the characteristics described > above, we consider the TGU as a helper in the CoreSight subsystem. > Its master device is the TPDM, which can transmit signals from other > subsystems, and we reuse the existing ports mechanism to link the TPDM to > the connected TGU. > > Here is a detailed example to explain how to use the TGU: > > In this example, the TGU is configured to use 2 conditions, 2 steps, and > the timer. The goal is to look for one of two patterns which are generated > from TPDM, giving priority to one, and then generate a trigger once the > timer reaches a certain value. In other words, two conditions are used > for the first step to look for the two patterns, where the one with the > highest priority is used in the first condition. Then, in the second step, > the timer is enabled and set to be compared to the given value at each > clock cycle. These steps are better shown below. > > |-----------------| > | | > | TPDM | > | | > |-----------------| > | > | > --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- ------ > | | | > | | |--------------------| | > | |---- ---> | | Go to next steps | | > | | | |--- ---> | Enable timer | | > | | v | | | | > | | |-----------------| | |--------------------| | > | | | | Yes | | | > | | | inputs==0xB | ----->| | <-------- | > | | | | | | No | | > | No | |-----------------| | v | | > | | | | |-----------------| | | > | | | | | | | | > | | | | | timer>=3 |-- | > | | v | | | | > | | |-----------------| | |-----------------| | > | | | | Yes | | | > | |--- | inputs==0xA | ----->| | Yes | > | | | | | > | |-----------------| v | > | |-----------------| | > | | | | > | | Trigger | | > | | | | > | |-----------------| | > | TGU | | > |--- --- --- --- --- --- --- --- --- --- --- --- --- --- |--- --- -- | > | > v > |-----------------| > |The controllers | > |which will use | > |triggers further | > |-----------------| > > steps: > 1. Reset TGU /*it will disable tgu and reset dataset*/ > - echo 1 > /sys/bus/coresight/devices/<tgu-name>/reset_tgu > > 2. Set the pattern match for priority0 to 0xA = 0b1010 and for > priority 1 to 0xB = 0b1011. > - echo 0x11113232 > /sys/bus/coresight/devices/<tgu-name>/step0_priority0/reg0 > - echo 0x11113233 > /sys/bus/coresight/devices/<tgu-name>/step0_priority1/reg0 > > Note: > Bit distribution diagram for each priority register > |-------------------------------------------------------------------| > | Bits | Field Nam | Description | > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 29:28 | SEL_BIT7_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 25:24 | SEL_BIT6_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 21:20 | SEL_BIT5_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 17:16 | SEL_BIT4_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 13:12 | SEL_BIT3_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 9:8 | SEL_BIT2_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 5:4 | SEL_BIT1_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > | | | 00 = bypass for OR output | > | 1:0 | SEL_BIT0_TYPE2 | 01 = bypass for AND output | > | | | 10 = sense input '0' is true| > | | | 11 = sense input '1' is true| > |-------------------------------------------------------------------| > These bits are used to identify the signals we want to sense, with > a maximum signal number of 140. For example, to sense the signal > 0xA (binary 1010), we set the value of bits 0 to 13 to 3232, which > represents 1010. The remaining bits are set to 1, as we want to use > AND gate to summarize all the signals we want to sense here. For > rising or falling edge detection of any input to the priority, set > the remaining bits to 0 to use an OR gate. > > 3. look for the pattern for priority_i i=0,1. > - echo 0x3 > /sys/bus/coresight/devices/<tgu-name>/step0_condition_decode/reg0 > - echo 0x30 > /sys/bus/coresight/devices/<tgu-name>/step0_condition_decode/reg1 > > |-------------------------------------------------------------------------------| > | Bits | Field Nam | Description | > |-------------------------------------------------------------------------------| > | | |For each decoded condition, this | > | 24 | NOT |inverts the output. If the condition | > | | |decodes to true, and the NOT field | > | | |is '1', then the output is NOT true. | > |-------------------------------------------------------------------------------| > | | |When '1' the output from the associated| > | 21 | BC0_COMP_ACTIVE |comparator will be actively included in| > | | |the decoding of this particular | > | | |condition. | > |-------------------------------------------------------------------------------| > | | |When '1' the output from the associated| > | | |comparator will need to be 1 to affect | > | 20 | BC0_COMP_HIGH |the decoding of this condition. | > | | |Conversely, a '0' here requires a '0' | > | | |from the comparator | > |-------------------------------------------------------------------------------| > | | |When '1' the output from the associated| > | 17 | |comparator will be actively included in| > | | TC0_COMP_ACTIVE |the decoding of this particular | > | | |condition. | > |-------------------------------------------------------------------------------| > | | |When '1' the output from the associated| > | | |comparator will need to be 1 to affect | > | 16 | TC0_COMP_HIGH |the decoding of this particular | > | | |condition.Conversely, a 0 here | > | | |requires a '0' from the comparator | > |-------------------------------------------------------------------------------| > | | |When '1' the output from Priority_n | > | | |OR logic will be actively | > | 4n+3 | Priority_n_OR_ACTIVE|included in the decoding of | > | | (n=0,1,2,3) |this particular condition. | > | | | | > |-------------------------------------------------------------------------------| > | | |When '1' the output from Priority_n | > | | |will need to be '1' to affect the | > | 4n+2 | Priority_n_OR_HIGH |decoding of this particular | > | | (n=0,1,2,3) |condition. Conversely, a '0' here | > | | |requires a '0' from Priority_n OR logic| > |-------------------------------------------------------------------------------| > | | |When '1' the output from Priority_n | > | | |AND logic will be actively | > | 4n+1 |Priority_n_AND_ACTIVE|included in the decoding of this | > | | (n=0,1,2,3) |particular condition. | > | | | | > |-------------------------------------------------------------------------------| > | | |When '1' the output from Priority_n | > | | |AND logic will need to be '1' to | > | 4n | Priority_n_AND_HIGH |affect the decoding of this | > | | (n=0,1,2,3) |particular condition. Conversely, | > | | |a '0' here requires a '0' from | > | | |Priority_n AND logic. | > |-------------------------------------------------------------------------------| > Since we use `priority_0` and `priority_1` with an AND output in step 2, we set `0x3` > and `0x30` here to activate them. > > 4. Set NEXT_STEP = 1 and TC0_ENABLE = 1 so that when the conditions > are met then the next step will be step 1 and the timer will be enabled. > - echo 0x20008 > /sys/bus/coresight/devices/<tgu-name>/step0_condition_select/reg0 > - echo 0x20008 > /sys/bus/coresight/devices/<tgu-name>/step0_condition_select/reg1 > > |-----------------------------------------------------------------------------| > | Bits | Field Nam | Description | > |-----------------------------------------------------------------------------| > | | |This field defines the next step the | > | 18:17 | NEXT_STEP |TGU will 'goto' for the associated | > | | |Condition and Step. | > |-----------------------------------------------------------------------------| > | | |For each possible output trigger | > | 13 | TRIGGER |available, set a '1' if you want | > | | |the trigger to go active for the | > | | |associated condition and Step. | > |-----------------------------------------------------------------------------| > | | |This will cause BC0 to increment if the| > | 9 | BC0_INC |associated Condition is decoded for | > | | |this step. | > |-----------------------------------------------------------------------------| > | | |This will cause BC0 to decrement if the| > | 8 | BC0_DEC |associated Condition is decoded for | > | | |this step. | > |-----------------------------------------------------------------------------| > | | |This will clear BC0 count value to 0 if| > | 7 | BC0_CLEAR |the associated Condition is decoded | > | | |for this step. | > |-----------------------------------------------------------------------------| > | | |This will cause TC0 to increment until | > | 3 | TC0_ENABLE |paused or cleared if the associated | > | | |Condition is decoded for this step. | > |-----------------------------------------------------------------------------| > | | |This will cause TC0 to pause until | > | 2 | TC0_PAUSE |enabled if the associated Condition | > | | |is decoded for this step. | > |-----------------------------------------------------------------------------| > | | |This will clear TC0 count value to 0 | > | 1 | TC0_CLEAR |if the associated Condition is | > | | |decoded for this step. | > |-----------------------------------------------------------------------------| > | | |This will set the done signal to the | > | 0 | DONE |TGU FSM if the associated Condition | > | | |is decoded for this step. | > |-----------------------------------------------------------------------------| > Based on the distribution diagram, we set `0x20008` for `priority0` and `priority1` to > achieve "jump to step 1 and enable TC0" once the signal is sensed. > > 5. activate the timer comparison for this step. > - echo 0x30000 > /sys/bus/coresight/devices/<tgu-name>/step1_condition_decode/reg0 > > |-------------------------------------------------------------------------------| > | | |When '1' the output from the associated| > | 17 | |comparator will be actively included in| > | | TC0_COMP_ACTIVE |the decoding of this particular | > | | |condition. | > |-------------------------------------------------------------------------------| > | | |When '1' the output from the associated| > | | |comparator will need to be 1 to affect | > | 16 | TC0_COMP_HIGH |the decoding of this particular | > | | |condition.Conversely, a 0 here | > | | |requires a '0' from the comparator | > |-------------------------------------------------------------------------------| > Accroding to the decode distribution diagram , we give 0x30000 here to set 16th&17th bit > to enable timer comparison. > > 6. Set the NEXT_STEP = 0 and TC0_PAUSE = 1 and TC0_CLEAR = 1 once the timer > has reached the given value. > - echo 0x6 > /sys/bus/coresight/devices/<tgu-name>/step1_condition_select/reg0 > > 7. Enable Trigger 0 for TGU when the condition 0 is met in step1, > i.e. when the timer reaches 3. > - echo 0x2000 > /sys/bus/coresight/devices/<tgu-name>/step1_condition_select/default > > Note: > 1. 'default' register allows for establishing the resultant action for > the default condition > > 2. Trigger:For each possible output trigger available from > the Design document, there are three triggers: interrupts, CTI, > and Cross-TGU mapping.All three triggers can occur, but > the choice of which trigger to use depends on the user's > needs. > > 8. Compare the timer to 3 in step 1. > - echo 0x3 > /sys/bus/coresight/devices/<tgu-name>/step1_timer/reg0 > > 9. enale tgu > - echo 1 > /sys/bus/coresight/devices/<tgu-name>/enable_tgu > --- > Link to V5: https://lore.kernel.org/all/20250529081949.26493-1-quic_songchai@quicinc.co… > > Changes in V6: > - Replace spinlock with guard(spinlock) in tgu_enable. > - Remove redundant blank line. > - Update publish date and contact member's name in "sysfs-bus-coresight-devices-tgu". > --- > Link to V4: https://patchwork.kernel.org/project/linux-arm-msm/cover/20250423101054.954… > > Changes in V5: > - Update publish date and kernel_version in "sysfs-bus-coresight-devices-tgu" > --- > Link to V3: https://lore.kernel.org/all/20250227092640.2666894-1-quic_songchai@quicinc.… > > Changes in V4: > - Add changlog in coverletter. > - Correct 'year' in Copyright in patch1. > - Correct port mechansim description in patch1. > - Remove 'tgu-steps','tgu-regs','tgu-conditions','tgu-timer-counters' from dt-binding > and set them through reading DEVID register as per Mike's suggestion. > - Modify tgu_disable func to make it have single return point in patch2 as per > Mike's suggestion. > - Use sysfs_emit in enable_tgu_show func in ptach2. > - Remove redundant judgement in enable_tgu_store in patch2. > - Correct typo in description in patch3. > - Set default ret as SYSFS_GROUP_INVISIBLE, and returnret at end in pacth3 as > per Mike's suggestion. > - Remove tgu_dataset_ro definition in patch3 > - Use #define constants with explanations of what they are rather than > arbitrary magic numbers in patch3 and patch4. > - Check -EINVAL before using 'calculate_array_location()' in array in patch4. > - Add 'default' in 'tgu_dataset_show''s switch part in patch4. > - Document the value needed to initiate the reset in pacth7. > - Check "value" in 'reset_tgu_store' and bail out with an error code if 0 in patch7. > - Remove dev_dbg in 'reset_tgu_store' in patch7. > --- > Link to V2: https://lore.kernel.org/all/20241010073917.16023-1-quic_songchai@quicinc.co… > > Changes in V3: > - Correct typo and format in dt-binding in patch1 > - Rebase to the latest kernel version > --- > Link to V1: https://lore.kernel.org/all/20240830092311.14400-1-quic_songchai@quicinc.co… > > Changes in V2: > - Use real name instead of login name, > - Correct typo and format in dt-binding and code. > - Bring order in tgu_prob(declarations with and without assignments) as per > Krzysztof's suggestion. > - Add module device table in patch2. > - Set const for tgu_common_grp and tgu_ids in patch2. > - Initialize 'data' in tgu_ids to fix the warning in pacth2. > --- > > Songwei Chai (7): > dt-bindings: arm: Add support for Coresight TGU trace > coresight: Add coresight TGU driver > coresight-tgu: Add signal priority support > coresight-tgu: Add TGU decode support > coresight-tgu: add support to configure next action > coresight-tgu: add timer/counter functionality for TGU > coresight-tgu: add reset node to initialize > > .../testing/sysfs-bus-coresight-devices-tgu | 51 ++ > .../bindings/arm/qcom,coresight-tgu.yaml | 92 +++ > drivers/hwtracing/coresight/Kconfig | 11 + > drivers/hwtracing/coresight/Makefile | 1 + > drivers/hwtracing/coresight/coresight-tgu.c | 776 ++++++++++++++++++ > drivers/hwtracing/coresight/coresight-tgu.h | 255 ++++++ > 6 files changed, 1186 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu > create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-tgu.yaml > create mode 100644 drivers/hwtracing/coresight/coresight-tgu.c > create mode 100644 drivers/hwtracing/coresight/coresight-tgu.h > > > As per the discussion here in v3 of this patchset > > https://lists.infradead.org/pipermail/linux-arm-kernel/2025-March/1012896.h… > > this component is primarily a part of the qualcom proprietary QPMDA > subsystem, and is capable of operating independently from the > CoreSight hardware trace generation system. > > The only link to Coresight is via the trigger input to CTI > component(s). CTI triggers can either be part of the ARM architected > or recommended connections between Coresight infrastructure from the > coresight specs and TRM documents, or platform specific triggers from > components external to coresight. For example on the Juno board a > trigger from the PL011 serial port is input to one of the system CTIs > on the board. > > Having Coresight management registers does not necessarily mean that > the component should be maintained under the hwtracing/coresight. Some > ARM Corelink interconnect components have the capability to generate > ATB trace into the coresight subsystem, and have some of the coresight > management registers. However, I would not expect the drivers for > these components to appear in hwtracing/coresight. > > As such this component could probably be better managed and maintained > as part of the /drivers/soc/qcom or similar area. > > The only changes to the Coresight infrastructure you should need to > get this component connected, is to alter the CTI declaration in board > device tree to add the incoming trigger as per the CTI bindings. > > Regards > > Mike > > Hi Mike, > > Thank you very much for your detailed feedback and for pointing out the architectural considerations > regarding the component's relationship with Coresight and the QPMDA subsystems. We fully understand > and appreciate your perspective on keeping the driver organization clean and aligned with subsystem boundaries. > > However, we would like to offer a slightly different view regarding the placement of this driver: > The TGU driver here exposes sysfs interfaces for user interaction and configuration. This kind of interface is generally not acceptable > under /driver/soc/qcom, which is typically reserved for passive platform drivers without user-facing interfaces. > > Given this, we'd like to ask your opinion on an alternative: > Would it be acceptable to create a new sub directory under /hwtracing/qcom to host this driver? > Alternatively, we could consider placing it under /driver/misc if that's more appropriate. > > Our preference would be place it under /driver/hwtracing/qcom, as this would provide a natural > home form Qualcomm-specific trace-related components that are adjacent to, but not strictly > part of, the Coresight architecture. This could also help organize future drivers that share similar > characteristics. > I am unsure on the procedure for creating new sub-directories for code in the kernel, but one key thing you do need is a maintainer for the code. The reason I suggested /driver/soc/qcom, was that this had qualcomm specific code with active maintainers. I recommend you consult with those responsible for maintaining qualcomm code within the kernel for the best course of action. Regards Mike > Looking forward to your thoughts. > > BRs, > Songwei > > > > > > -- > Mike Leach > Principal Engineer, ARM Ltd. > Manchester Design Centre. UK > -- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK

1 month, 3 weeks

Re: [GIT PULL] coresight: updates for Linux v6.17

by Suzuki K Poulose

Hi Greg On 25/07/2025 10:47, Greg KH wrote: > On Fri, Jul 25, 2025 at 10:21:21AM +0100, Suzuki K Poulose wrote: >> Hi Greg >> >> Apologies for the late pull request. Please find the updates for v6.17 >> >> Kindly pull >> >> Suzuki >> >> >> >> The following changes since commit 86731a2a651e58953fc949573895f2fa6d456841: >> >> Linux 6.16-rc3 (2025-06-22 13:30:08 -0700) >> >> are available in the Git repository at: >> >> git://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux.git tags/coresight-next-v6.17 >> >> for you to fetch changes up to 2b52cf338d39d684a1c6af298e8204902c026aca: >> >> coresight: Refactor runtime PM (2025-07-25 09:47:13 +0100) >> >> ---------------------------------------------------------------- >> coresight: Updates for Linux v6.17 >> >> CoreSight selfhosted tracing subsystem updates for v6.17, includes: >> - Qualcomm CoreSight TNOC driver >> - Cleanup of CoreSight clocks for the subsystem >> - Miscellaneous fixes >> >> Signed-off-by: Suzuki K Poulose <suzuki.poulose(a)arm.com> > > This all is really late, I wanted to close my tree a few days ago :( > > As this hasn't even been in linux-next yet, and I need to send a pull > request for this on Monday, that's not going to give any time at all > here in linux-next. I understand. > > How about you wait until after -rc1 and then just send me 2 requests, > one for bugfixes, and one for new stuff for 6.18-rc1? I could get you one with the stuff that was already on -next, dropping the last series I merged. But I guess we can wait until the merge window as you suggested. Kind regards Suzuki > > thanks, > > greg k-h

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CoreSight July 2025