Message ID | 20250207064213.2314482-1-quic_jiegan@quicinc.com (mailing list archive) |
---|---|
Headers | show |
Series | Coresight: Add Coresight TMC Control Unit driver | expand |
On 07/02/2025 6:42 am, Jie Gan wrote: > The Coresight TMC Control Unit(CTCU) device hosts miscellaneous configuration > registers to control various features related to TMC ETR device. > > The CTCU device works as a helper device physically connected to the TMC ETR device. > --------------------------------------------------------- > |ETR0| |ETR1| > . \ / . > . \ / . > . \ / . > . \ / . > --------------------------------------------------- > ETR0ATID0-ETR0ATID3 CTCU ETR1ATID0-ETR1ATID3 > --------------------------------------------------- > Each ETR has four ATID registers with 128 bits long in total. > e.g. ETR0ATID0-ETR0ATID3 registers are used by ETR0 device. > > Based on the trace id which is programed in CTCU ATID register of > specific ETR, trace data with that trace id can get into ETR's buffer > while other trace data gets ignored. The number of CTCU ATID registers > depends on the number of defined TMC ETR devices. For example, two TMC > ETR devices need eight ATID registers. ETR0 with ETR0ATID0-ETR0ATID3 > and ETR1 with ETR1ATID0-ETRATID3. > > The significant challenge in enabling the data filter function is how > to collect the trace ID of the source device. The introduction of > trace_id callback function addresses this challenge. The callback function > collects trace ID of the device and return it back. The trace ID will be > stored in the structure called coresight_path and transmitted to helper > and sink devices. > > The coresight_path structure is created to address how to transmit > parameters needs by coresight_enable_path/coresight_disbale_path > functions. > > Here is the definition of the struct coresight_path: > /** > * struct coresight_path - data needed by enable/disable path > * @path: path from source to sink. > * @trace_id: trace_id of the whole path. > */ > struct coresight_path { > struct list_head *path; > u8 trace_id; > }; > > The atid_offset mentioned before is the offset to ATID register in CTCU > device. > > Enabling the source device will configure one bit in the ATID register based > on its trace ID. > Disabling the source devices will reset the bit in the AITD register > based on its trace ID. > > Useage: > Enable: > STM device with trace ID 5 and ETR0 is activated. > Bitmap before the enablement: > ETR0ATID0: > 31..................543210 > ========================== > 0000000000000000000000...0 > ========================== > > Bitmap after the enablement: > 31..................543210 > ========================== > 0000000000000...0000100000 > ========================== > > The bit 5 of the ETR0ATID0 register is configured to 1 when enabling the > STM device. > > Disable: > STM device with trace ID 5 and ETR0 is activated. > Bitmap before the disablement: > ETR0ATID0: > 31................6543210 > ========================= > 000000000010111...0100000 > ========================= > > Bitmap after the disablement > ETR0ATID0: > 31................6543210 > ========================= > 000000000010111...0000000 > ========================= > > The bit 5 of the ETR0ATID0 register is reset to 0 when disabling the STM > device. > > Sincere thanks to James Clark for providing an excellent idea to handle > the trace_id of the path. > > Changes in V2: > 1. Rename the device to Coresight Control Unit. > 2. Introduce the trace_id function pointer to address the challeng how to > properly collect the trace ID of the device. > 3. Introduce a new way to define the qcom,ccu-atid-offset property in > device tree. > 4. Disabling the filter function blocked on acquiring the ATID-offset, > which will be addressed in a separate patch once it’s ready. > Link to V1 - https://lore.kernel.org/lkml/20240618072726.3767974-1-quic_jiegan@quicinc.com/T/#t > > Changes in V3: > 1. Rename the device to Coresight TMC Control Unit(CTCU). > 2. Introduce a new way to define the platform related configs. The new > structure, qcom_ctcu_config, is used to store configurations specific > to a platform. Each platform should have its own qcom_ctcu_config structure. > 3. In perf mode, the ETM devices allocate their trace IDs using the > perf_sink_id_map. In sysfs mode, the ETM devices allocate their trace > IDs using the id_map_default. > 4. Considering the scenario where both ETR devices might be enabled simultaneously > with multiple sources, retrieving and using trace IDs instead of id_map is more effective > for the CTCU device in sysfs mode. For example, We can configure one ETR as sink for high > throughput trace data like ETM and another ETR for low throughput trace data like STM. > In this case, STM data won’t be flushed out by ETM data quickly. However, if we use id_map to > manage the trace IDs, we need to create a separate id_map for each ETR device. Addtionally, We > would need to iterate through the entire id_map for each configuration. > 5. Add support for apb's clock name "apb". If the function fails to obtain the clock with > the name "apb_pclk", it will attempt to acquire the clock with the name "apb". > Link to V2 - https://lore.kernel.org/linux-arm-msm/20240705090049.1656986-1-quic_jiegan@quicinc.com/T/#t > > Changes in V4: > 1. Add TMC description in binding file. > 2. Restrict the number of ports for the CTCU device to a range of 0 to 1 in the binding file, > because the maximum number of CTCU devices is 2 for existing projects. > Link to V3 - https://lore.kernel.org/linux-arm-kernel/20240812024141.2867655-1-quic_jiegan@quicinc.com/ > > Changes in V5: > 1. Fix the format issue for description paragrah in dt binding file. > 2. Previous discussion for why use "in-ports" property instead of "ports". > Link to V4 - https://lore.kernel.org/linux-arm-msm/20240828012706.543605-1-quic_jiegan@quicinc.com/ > > Changes in V6: > 1. Collected reviewed-by tag from Rob for dt-binding patch. > 2. Rebased on tag next-20241008. > 3. Dropped all depends-on tags. > Link to V5 - https://lore.kernel.org/linux-arm-msm/20240909033458.3118238-1-quic_jiegan@quicinc.com/ > > Changes in V7: > 1. Rebased on tag next-20241204. > 2. Fix format issue for dts patch. > - Padding the address part to 8 digits > Link to V6 - https://lore.kernel.org/linux-arm-msm/20241009112503.1851585-1-quic_jiegan@quicinc.com/ > > Changes in V8: > 1. Rebased on tag next-20241220. > 2. Use raw_spinlock_t instead of spinlock_t. > 3. Remove redundant codes in CTCU driver: > - Eliminate unnecessary parameter validations. > - Correct log level when an error occurs. > - Optimize codes. > 4. Correct the subject prefix for DT patch. > 5. Collected reviewed-by tag from Konrad Dybcib for DT patch. > Link to V7 - https://lore.kernel.org/all/20241210031545.3468561-1-quic_jiegan@quicinc.com/ > > Changes in V9: > 1. Rebased on tag next-20250113. > 2. Separate the previous trace_id patch (patch 2/5 Coresight: Add trace_id function to > retrieving the trace ID) into two patches. > 3. Introduce a new struct coresight_path instead of cs_sink_data which was > created in previous version. The coresight_path will be initialized > and constructed in coresight_build_path function and released by > coresight_release_path function. > Detail of the struct coresight_path is shown below: > /** > * struct coresight_path - data needed by enable/disable path > * @path: path from source to sink. > * @trace_id: trace_id of the whole path. > */ > struct coresight_path { > struct list_head *path; > u8 trace_id; > }; > > 4. Introduce an array of atomic in CTCU driver to represent the refcnt or each > enabled trace_id for each sink. The reason is there is a scenario that more > than one TPDM device physically connected to the same TPDA device has > been enabled. The CTCU driver must verify the refcnt before resetting the > bit of the atid register according to the trace_id of the TPDA device. > 5. Remove redundant codes in CTCU driver. > 6. Add reviewed-by tag to the commit message for APB clock path(patch > 1/5). > Link to V8 - https://lore.kernel.org/all/20241226011022.1477160-1-quic_jiegan@quicinc.com/ > > Changes in V10: > 1. Introduce a new API to allocate and read trace_id after path is built. > 2. Introduce a new API to allocate and read trace_id of ETM device. > 3. Add a new patch: [PATCH v10 3/7] Coresight: Use coresight_etm_get_trace_id() in traceid_show() > 4. Remove perf handle from coresight_path. > 5. Use u8 instead of atomic_t for traceid_refcnt. > 6. Optimize the part of code in CTCU drvier that is responsible for program atid register. > Link to V9 - https://lore.kernel.org/all/20250124072537.1801030-1-quic_jiegan@quicinc.com/ > > Jie Gan (7): > Coresight: Add support for new APB clock name > Coresight: Add trace_id function to retrieving the trace ID > Coresight: Use coresight_etm_get_trace_id() in traceid_show() > Coresight: Introduce a new struct coresight_path > dt-bindings: arm: Add Coresight TMC Control Unit hardware > Coresight: Add Coresight TMC Control Unit driver > arm64: dts: qcom: sa8775p: Add CTCU and ETR nodes > > .../bindings/arm/qcom,coresight-ctcu.yaml | 84 ++++++ > arch/arm64/boot/dts/qcom/sa8775p.dtsi | 153 ++++++++++ > drivers/hwtracing/coresight/Kconfig | 12 + > drivers/hwtracing/coresight/Makefile | 1 + > drivers/hwtracing/coresight/coresight-core.c | 133 +++++++-- > drivers/hwtracing/coresight/coresight-ctcu.c | 268 ++++++++++++++++++ > drivers/hwtracing/coresight/coresight-ctcu.h | 24 ++ > drivers/hwtracing/coresight/coresight-dummy.c | 16 +- > .../hwtracing/coresight/coresight-etm-perf.c | 30 +- > .../hwtracing/coresight/coresight-etm-perf.h | 2 +- > drivers/hwtracing/coresight/coresight-etm.h | 1 - > .../coresight/coresight-etm3x-core.c | 55 +--- > .../coresight/coresight-etm3x-sysfs.c | 3 +- > .../coresight/coresight-etm4x-core.c | 55 +--- > .../coresight/coresight-etm4x-sysfs.c | 4 +- > drivers/hwtracing/coresight/coresight-etm4x.h | 1 - > drivers/hwtracing/coresight/coresight-priv.h | 12 +- > drivers/hwtracing/coresight/coresight-stm.c | 14 +- > drivers/hwtracing/coresight/coresight-sysfs.c | 17 +- > drivers/hwtracing/coresight/coresight-tpda.c | 11 + > drivers/hwtracing/coresight/coresight-tpdm.c | 3 +- > include/linux/coresight.h | 30 +- > 22 files changed, 765 insertions(+), 164 deletions(-) > create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml > create mode 100644 drivers/hwtracing/coresight/coresight-ctcu.c > create mode 100644 drivers/hwtracing/coresight/coresight-ctcu.h > Just one small comment, and the kernel test bot report to fix. Otherwise looks good to me. Reviewed-by: James Clark <james.clark@linaro.org>
On 2/14/2025 12:01 AM, James Clark wrote: > > > On 07/02/2025 6:42 am, Jie Gan wrote: >> The Coresight TMC Control Unit(CTCU) device hosts miscellaneous >> configuration >> registers to control various features related to TMC ETR device. >> >> The CTCU device works as a helper device physically connected to the >> TMC ETR device. >> --------------------------------------------------------- >> |ETR0| |ETR1| >> . \ / . >> . \ / . >> . \ / . >> . \ / . >> --------------------------------------------------- >> ETR0ATID0-ETR0ATID3 CTCU ETR1ATID0-ETR1ATID3 >> --------------------------------------------------- >> Each ETR has four ATID registers with 128 bits long in total. >> e.g. ETR0ATID0-ETR0ATID3 registers are used by ETR0 device. >> >> Based on the trace id which is programed in CTCU ATID register of >> specific ETR, trace data with that trace id can get into ETR's buffer >> while other trace data gets ignored. The number of CTCU ATID registers >> depends on the number of defined TMC ETR devices. For example, two TMC >> ETR devices need eight ATID registers. ETR0 with ETR0ATID0-ETR0ATID3 >> and ETR1 with ETR1ATID0-ETRATID3. >> >> The significant challenge in enabling the data filter function is how >> to collect the trace ID of the source device. The introduction of >> trace_id callback function addresses this challenge. The callback >> function >> collects trace ID of the device and return it back. The trace ID will be >> stored in the structure called coresight_path and transmitted to helper >> and sink devices. >> >> The coresight_path structure is created to address how to transmit >> parameters needs by coresight_enable_path/coresight_disbale_path >> functions. >> >> Here is the definition of the struct coresight_path: >> /** >> * struct coresight_path - data needed by enable/disable path >> * @path: path from source to sink. >> * @trace_id: trace_id of the whole path. >> */ >> struct coresight_path { >> struct list_head *path; >> u8 trace_id; >> }; >> >> The atid_offset mentioned before is the offset to ATID register in CTCU >> device. >> >> Enabling the source device will configure one bit in the ATID register >> based >> on its trace ID. >> Disabling the source devices will reset the bit in the AITD register >> based on its trace ID. >> >> Useage: >> Enable: >> STM device with trace ID 5 and ETR0 is activated. >> Bitmap before the enablement: >> ETR0ATID0: >> 31..................543210 >> ========================== >> 0000000000000000000000...0 >> ========================== >> >> Bitmap after the enablement: >> 31..................543210 >> ========================== >> 0000000000000...0000100000 >> ========================== >> >> The bit 5 of the ETR0ATID0 register is configured to 1 when enabling the >> STM device. >> >> Disable: >> STM device with trace ID 5 and ETR0 is activated. >> Bitmap before the disablement: >> ETR0ATID0: >> 31................6543210 >> ========================= >> 000000000010111...0100000 >> ========================= >> >> Bitmap after the disablement >> ETR0ATID0: >> 31................6543210 >> ========================= >> 000000000010111...0000000 >> ========================= >> >> The bit 5 of the ETR0ATID0 register is reset to 0 when disabling the STM >> device. >> >> Sincere thanks to James Clark for providing an excellent idea to handle >> the trace_id of the path. >> >> Changes in V2: >> 1. Rename the device to Coresight Control Unit. >> 2. Introduce the trace_id function pointer to address the challeng how to >> properly collect the trace ID of the device. >> 3. Introduce a new way to define the qcom,ccu-atid-offset property in >> device tree. >> 4. Disabling the filter function blocked on acquiring the ATID-offset, >> which will be addressed in a separate patch once it’s ready. >> Link to V1 - https://lore.kernel.org/lkml/20240618072726.3767974-1- >> quic_jiegan@quicinc.com/T/#t >> >> Changes in V3: >> 1. Rename the device to Coresight TMC Control Unit(CTCU). >> 2. Introduce a new way to define the platform related configs. The new >> structure, qcom_ctcu_config, is used to store configurations specific >> to a platform. Each platform should have its own qcom_ctcu_config >> structure. >> 3. In perf mode, the ETM devices allocate their trace IDs using the >> perf_sink_id_map. In sysfs mode, the ETM devices allocate their trace >> IDs using the id_map_default. >> 4. Considering the scenario where both ETR devices might be enabled >> simultaneously >> with multiple sources, retrieving and using trace IDs instead of >> id_map is more effective >> for the CTCU device in sysfs mode. For example, We can configure >> one ETR as sink for high >> throughput trace data like ETM and another ETR for low throughput >> trace data like STM. >> In this case, STM data won’t be flushed out by ETM data quickly. >> However, if we use id_map to >> manage the trace IDs, we need to create a separate id_map for each >> ETR device. Addtionally, We >> would need to iterate through the entire id_map for each >> configuration. >> 5. Add support for apb's clock name "apb". If the function fails to >> obtain the clock with >> the name "apb_pclk", it will attempt to acquire the clock with the >> name "apb". >> Link to V2 - https://lore.kernel.org/linux-arm- >> msm/20240705090049.1656986-1-quic_jiegan@quicinc.com/T/#t >> >> Changes in V4: >> 1. Add TMC description in binding file. >> 2. Restrict the number of ports for the CTCU device to a range of 0 to >> 1 in the binding file, >> because the maximum number of CTCU devices is 2 for existing >> projects. >> Link to V3 - https://lore.kernel.org/linux-arm- >> kernel/20240812024141.2867655-1-quic_jiegan@quicinc.com/ >> >> Changes in V5: >> 1. Fix the format issue for description paragrah in dt binding file. >> 2. Previous discussion for why use "in-ports" property instead of >> "ports". >> Link to V4 - https://lore.kernel.org/linux-arm- >> msm/20240828012706.543605-1-quic_jiegan@quicinc.com/ >> >> Changes in V6: >> 1. Collected reviewed-by tag from Rob for dt-binding patch. >> 2. Rebased on tag next-20241008. >> 3. Dropped all depends-on tags. >> Link to V5 - https://lore.kernel.org/linux-arm- >> msm/20240909033458.3118238-1-quic_jiegan@quicinc.com/ >> >> Changes in V7: >> 1. Rebased on tag next-20241204. >> 2. Fix format issue for dts patch. >> - Padding the address part to 8 digits >> Link to V6 - https://lore.kernel.org/linux-arm- >> msm/20241009112503.1851585-1-quic_jiegan@quicinc.com/ >> >> Changes in V8: >> 1. Rebased on tag next-20241220. >> 2. Use raw_spinlock_t instead of spinlock_t. >> 3. Remove redundant codes in CTCU driver: >> - Eliminate unnecessary parameter validations. >> - Correct log level when an error occurs. >> - Optimize codes. >> 4. Correct the subject prefix for DT patch. >> 5. Collected reviewed-by tag from Konrad Dybcib for DT patch. >> Link to V7 - https://lore.kernel.org/all/20241210031545.3468561-1- >> quic_jiegan@quicinc.com/ >> >> Changes in V9: >> 1. Rebased on tag next-20250113. >> 2. Separate the previous trace_id patch (patch 2/5 Coresight: Add >> trace_id function to >> retrieving the trace ID) into two patches. >> 3. Introduce a new struct coresight_path instead of cs_sink_data which >> was >> created in previous version. The coresight_path will be initialized >> and constructed in coresight_build_path function and released by >> coresight_release_path function. >> Detail of the struct coresight_path is shown below: >> /** >> * struct coresight_path - data needed by enable/disable path >> * @path: path from source to sink. >> * @trace_id: trace_id of the whole path. >> */ >> struct coresight_path { >> struct list_head *path; >> u8 trace_id; >> }; >> >> 4. Introduce an array of atomic in CTCU driver to represent the refcnt >> or each >> enabled trace_id for each sink. The reason is there is a scenario >> that more >> than one TPDM device physically connected to the same TPDA device has >> been enabled. The CTCU driver must verify the refcnt before >> resetting the >> bit of the atid register according to the trace_id of the TPDA >> device. >> 5. Remove redundant codes in CTCU driver. >> 6. Add reviewed-by tag to the commit message for APB clock path(patch >> 1/5). >> Link to V8 - https://lore.kernel.org/all/20241226011022.1477160-1- >> quic_jiegan@quicinc.com/ >> >> Changes in V10: >> 1. Introduce a new API to allocate and read trace_id after path is built. >> 2. Introduce a new API to allocate and read trace_id of ETM device. >> 3. Add a new patch: [PATCH v10 3/7] Coresight: Use >> coresight_etm_get_trace_id() in traceid_show() >> 4. Remove perf handle from coresight_path. >> 5. Use u8 instead of atomic_t for traceid_refcnt. >> 6. Optimize the part of code in CTCU drvier that is responsible for >> program atid register. >> Link to V9 - https://lore.kernel.org/all/20250124072537.1801030-1- >> quic_jiegan@quicinc.com/ >> >> Jie Gan (7): >> Coresight: Add support for new APB clock name >> Coresight: Add trace_id function to retrieving the trace ID >> Coresight: Use coresight_etm_get_trace_id() in traceid_show() >> Coresight: Introduce a new struct coresight_path >> dt-bindings: arm: Add Coresight TMC Control Unit hardware >> Coresight: Add Coresight TMC Control Unit driver >> arm64: dts: qcom: sa8775p: Add CTCU and ETR nodes >> >> .../bindings/arm/qcom,coresight-ctcu.yaml | 84 ++++++ >> arch/arm64/boot/dts/qcom/sa8775p.dtsi | 153 ++++++++++ >> drivers/hwtracing/coresight/Kconfig | 12 + >> drivers/hwtracing/coresight/Makefile | 1 + >> drivers/hwtracing/coresight/coresight-core.c | 133 +++++++-- >> drivers/hwtracing/coresight/coresight-ctcu.c | 268 ++++++++++++++++++ >> drivers/hwtracing/coresight/coresight-ctcu.h | 24 ++ >> drivers/hwtracing/coresight/coresight-dummy.c | 16 +- >> .../hwtracing/coresight/coresight-etm-perf.c | 30 +- >> .../hwtracing/coresight/coresight-etm-perf.h | 2 +- >> drivers/hwtracing/coresight/coresight-etm.h | 1 - >> .../coresight/coresight-etm3x-core.c | 55 +--- >> .../coresight/coresight-etm3x-sysfs.c | 3 +- >> .../coresight/coresight-etm4x-core.c | 55 +--- >> .../coresight/coresight-etm4x-sysfs.c | 4 +- >> drivers/hwtracing/coresight/coresight-etm4x.h | 1 - >> drivers/hwtracing/coresight/coresight-priv.h | 12 +- >> drivers/hwtracing/coresight/coresight-stm.c | 14 +- >> drivers/hwtracing/coresight/coresight-sysfs.c | 17 +- >> drivers/hwtracing/coresight/coresight-tpda.c | 11 + >> drivers/hwtracing/coresight/coresight-tpdm.c | 3 +- >> include/linux/coresight.h | 30 +- >> 22 files changed, 765 insertions(+), 164 deletions(-) >> create mode 100644 Documentation/devicetree/bindings/arm/ >> qcom,coresight-ctcu.yaml >> create mode 100644 drivers/hwtracing/coresight/coresight-ctcu.c >> create mode 100644 drivers/hwtracing/coresight/coresight-ctcu.h >> > > Just one small comment, and the kernel test bot report to fix. Otherwise > looks good to me. > > Reviewed-by: James Clark <james.clark@linaro.org> > Hi James, Thanks for the comments and contributions. Will send V11 to address the comments. Jie