CoreSight December 2025

coresight@lists.linaro.org

6 participants
46 discussions

Re: [PATCH v8 0/7] Provides support for Trigger Generation Unit

by Suzuki K Poulose

Cc: Greg On 03/12/2025 09:00, Songwei Chai wrote: > We propose creating a new qcom directory under drivers/hwtracing > to host this TGU driver, as well as additional Qualcomm-specific > hwtracing drivers that we plan to submit in the coming months. > This structure will help organize vendor-specific implementations > and facilitate future development and maintenance. > > Feedback from the community on this proposal is highly appreciated. > > - Why we are proposing this: > > TGU has the ability to monitor signal conditions and trigger debug-related > actions, serving as a programmable hardware component that enhances system > trace and debug capabilities. Placing it under drivers/hwtracing aligns with > its function as a trace generation utility. > > We previously attempted to push this driver to drivers/hwtracing/coresight, > but did not receive support from the maintainers of the CoreSight subsystem. > The reason provided was: “This component is primarily a part of the > Qualcomm proprietary QPMDA subsystem, and is capable of operating > independently from the CoreSight hardware trace generation system.” > > Chat history : https://lore.kernel.org/all/CAJ9a7ViKxHThyZfFFDV_FkNRimk4uo1NrMtQ-kcaj1qO4Z… > > Given this, we have been considering whether it would be appropriate > to create a dedicated drivers/hwtracing/qcom directory for > Qualcomm-related hwtracing drivers. This would follow the precedent set > by Intel, which maintains its own directory at drivers/hwtracing/intel_th. > We believe this structure would significantly facilitate > future submissions of related Qualcomm drivers. > > - Maintenance of drivers/hwtracing/qcom: > Fine by, me. > Bjorn, who maintains linux-arm-msm, will be the maintainer of this > directory — we’ve discussed this with him and he’s aware that his task > list may grow accordingly. Additionally, Qualcomm engineers familiar with > the debug hardware — such as [Tingwei Zhang, Jinlong Mao, Songwei Chai], > will be available to review incoming patches and support ongoing > development. > > - Detail for TGU: > > This component 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. Please remove the coresight_device and other dependencies. You may use generic bits, CS_LOCK/UNLOCK etc. But including coresight-priv.h is not something I would prefer. It brings in unnecessary dependencies between two subsystems and I don't see any reason for using -priv.h. It is named as it is, for a reason, coresight private definitions. > > 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 Why do they need to be coresight devices and appear on the coresight bus if they are not coresight devices ? As I understand they are simply devices with some sysfs knobs. Otherwise, happy with the proposal Suzuki > > 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 V7: https://lore.kernel.org/all/20251104064043.88972-1-songwei.chai@oss.qualcom… > > Changes in V8: > - Add "select" section in bindings. > - Update publish date in "sysfs-bus-coresight-devices-tgu". > --- > Link to V6: https://lore.kernel.org/all/20250709104114.22240-1-songchai@qti.qualcomm.co… > > Changes in V7: > - Move the TGU code location from 'drivers/hwtracing/coresight/' to 'drivers/hwtracing/qcom/'. > - Rename the spinlock used in the code from 'spinlock' to 'lock'. > - Perform the 'calculate_array_location' separately, instead of doing it within the function. > - Update the sender email address. > --- > 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 Qualcomm TGU trace > qcom-tgu: Add TGU driver > qcom-tgu: Add signal priority support > qcom-tgu: Add TGU decode support > qcom-tgu: Add support to configure next action > qcom-tgu: Add timer/counter functionality for TGU > qcom-tgu: Add reset node to initialize > > .../testing/sysfs-bus-coresight-devices-tgu | 51 ++ > .../devicetree/bindings/arm/qcom,tgu.yaml | 92 +++ > drivers/Makefile | 1 + > drivers/hwtracing/Kconfig | 2 + > drivers/hwtracing/qcom/Kconfig | 18 + > drivers/hwtracing/qcom/Makefile | 3 + > drivers/hwtracing/qcom/tgu.c | 737 ++++++++++++++++++ > drivers/hwtracing/qcom/tgu.h | 252 ++++++ > 8 files changed, 1156 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu > create mode 100644 Documentation/devicetree/bindings/arm/qcom,tgu.yaml > create mode 100644 drivers/hwtracing/qcom/Kconfig > create mode 100644 drivers/hwtracing/qcom/Makefile > create mode 100644 drivers/hwtracing/qcom/tgu.c > create mode 100644 drivers/hwtracing/qcom/tgu.h >

3 weeks, 3 days

Re: [PATCH v6 6/9] dt-bindings: arm: add an interrupt property for Coresight CTCU

by Mike Leach

On Mon, 8 Sept 2025 at 03:02, Jie Gan <jie.gan(a)oss.qualcomm.com> wrote: > > Add an interrupt property to CTCU device. The interrupt will be triggered > when the data size in the ETR buffer exceeds the threshold of the > BYTECNTRVAL register. Programming a threshold in the BYTECNTRVAL register > of CTCU device will enable the interrupt. > > Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org> > Signed-off-by: Jie Gan <jie.gan(a)oss.qualcomm.com> > --- > .../devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml > index 843b52eaf872..ea05ad8f3dd3 100644 > --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml > +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml > @@ -39,6 +39,16 @@ properties: > items: > - const: apb > > + interrupts: > + items: > + - description: Byte cntr interrupt for etr0 > + - description: Byte cntr interrupt for etr1 > + > + interrupt-names: > + items: > + - const: etr0 > + - const: etr1 > + > in-ports: > $ref: /schemas/graph.yaml#/properties/ports > > @@ -56,6 +66,8 @@ additionalProperties: false > > examples: > - | > + #include <dt-bindings/interrupt-controller/arm-gic.h> > + > ctcu@1001000 { > compatible = "qcom,sa8775p-ctcu"; > reg = <0x1001000 0x1000>; > @@ -63,6 +75,11 @@ examples: > clocks = <&aoss_qmp>; > clock-names = "apb"; > > + interrupts = <GIC_SPI 270 IRQ_TYPE_EDGE_RISING>, > + <GIC_SPI 262 IRQ_TYPE_EDGE_RISING>; > + interrupt-names = "etr0", > + "etr1"; > + > in-ports { > #address-cells = <1>; > #size-cells = <0>; > > -- > 2.34.1 > Not sure if you need me to review this purely DT hardware description update but... Reviewed-by: Mike Leach <mike.leach(a)linaro.org> -- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK

3 weeks, 3 days

Re: [PATCH v6 4/9] coresight: tmc: add create/clean functions for etr_buf_list

by Mike Leach

On Mon, 8 Sept 2025 at 03:02, Jie Gan <jie.gan(a)oss.qualcomm.com> wrote: > > Create and insert or remove the etr_buf_node to/from the etr_buf_list. > > Signed-off-by: Jie Gan <jie.gan(a)oss.qualcomm.com> > --- > drivers/hwtracing/coresight/coresight-tmc-etr.c | 94 +++++++++++++++++++++++++ > drivers/hwtracing/coresight/coresight-tmc.h | 2 + > 2 files changed, 96 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c > index b07fcdb3fe1a..ed15991b3217 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c > +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c > @@ -1909,6 +1909,100 @@ const struct coresight_ops tmc_etr_cs_ops = { > .panic_ops = &tmc_etr_sync_ops, > }; > > +/** > + * tmc_clean_etr_buf_list - clean the etr_buf_list. > + * @drvdata: driver data of the TMC device. > + * > + * Remove the allocated node from the list and free the extra buffer. > + */ > +void tmc_clean_etr_buf_list(struct tmc_drvdata *drvdata) > +{ > + struct etr_buf_node *nd, *next; > + > + list_for_each_entry_safe(nd, next, &drvdata->etr_buf_list, node) { > + if (nd->sysfs_buf == drvdata->sysfs_buf) { > + if (coresight_get_mode(drvdata->csdev) == CS_MODE_DISABLED) { > + drvdata->sysfs_buf = NULL; > + tmc_free_etr_buf(nd->sysfs_buf); > + nd->sysfs_buf = NULL; > + } > + list_del(&nd->node); > + kfree(nd); > + } else { > + /* Free allocated buffers which are not utilized by ETR */ > + list_del(&nd->node); > + tmc_free_etr_buf(nd->sysfs_buf); > + nd->sysfs_buf = NULL; > + kfree(nd); > + } > + } > +} > +EXPORT_SYMBOL_GPL(tmc_clean_etr_buf_list); > + > +/** > + * tmc_create_etr_buf_list - create a list to manage the etr_buf_node. > + * @drvdata: driver data of the TMC device. > + * @num_nodes: number of nodes want to create with the list. > + * > + * Return 0 upon success and return the error number if fail. > + */ > +int tmc_create_etr_buf_list(struct tmc_drvdata *drvdata, int num_nodes) > +{ > + struct etr_buf_node *new_node; > + struct etr_buf *sysfs_buf; > + int i = 0, ret = 0; > + > + /* We dont need a list if there is only one node */ > + if (num_nodes < 2) > + return -EINVAL; > + > + /* We expect that sysfs_buf in drvdata has already been allocated. */ > + if (drvdata->sysfs_buf) { > + /* Directly insert the allocated sysfs_buf into the list first */ > + new_node = kzalloc(sizeof(struct etr_buf_node), GFP_KERNEL); > + if (IS_ERR(new_node)) > + return PTR_ERR(new_node); > + > + new_node->sysfs_buf = drvdata->sysfs_buf; > + new_node->is_free = false; > + list_add(&new_node->node, &drvdata->etr_buf_list); > + i++; > + } > + > + while (i < num_nodes) { > + new_node = kzalloc(sizeof(struct etr_buf_node), GFP_KERNEL); > + if (IS_ERR(new_node)) { > + ret = PTR_ERR(new_node); > + break; > + } > + > + sysfs_buf = tmc_alloc_etr_buf(drvdata, drvdata->size, 0, cpu_to_node(0), NULL); > + if (IS_ERR(sysfs_buf)) { > + kfree(new_node); > + ret = PTR_ERR(new_node); > + break; > + } > + > + /* We dont have a available sysfs_buf in drvdata, setup one */ > + if (!drvdata->sysfs_buf) { > + drvdata->sysfs_buf = sysfs_buf; > + new_node->is_free = false; > + } else > + new_node->is_free = true; > + > + new_node->sysfs_buf = sysfs_buf; > + list_add(&new_node->node, &drvdata->etr_buf_list); > + i++; > + } > + > + /* Clean the list if there is an error */ > + if (ret) > + tmc_clean_etr_buf_list(drvdata); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(tmc_create_etr_buf_list); > + > int tmc_read_prepare_etr(struct tmc_drvdata *drvdata) > { > int ret = 0; > diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h > index 292e25d82b62..ca0cba860d5f 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc.h > +++ b/drivers/hwtracing/coresight/coresight-tmc.h > @@ -459,5 +459,7 @@ void tmc_etr_remove_catu_ops(void); > struct etr_buf *tmc_etr_get_buffer(struct coresight_device *csdev, > enum cs_mode mode, void *data); > extern const struct attribute_group coresight_etr_group; > +void tmc_clean_etr_buf_list(struct tmc_drvdata *drvdata); > +int tmc_create_etr_buf_list(struct tmc_drvdata *drvdata, int num_nodes); > > #endif > > -- > 2.34.1 > Reviewed-by: Mike Leach <mike.leach(a)linaro.org> -- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK

3 weeks, 3 days

Re: [PATCH v6 3/9] coresight: tmc: add etr_buf_list to store allocated etr_buf

by Mike Leach

On Mon, 8 Sept 2025 at 03:02, Jie Gan <jie.gan(a)oss.qualcomm.com> wrote: > > Add a list to store allocated etr_buf. > > The byte-cntr functionality requires two etr_buf to receive trace data. > The active etr_buf collects the trace data from source device, while the > byte-cntr reading function accesses the deactivated etr_buf after is > has been filled and synced, transferring data to the userspace. > > Signed-off-by: Jie Gan <jie.gan(a)oss.qualcomm.com> > --- > drivers/hwtracing/coresight/coresight-tmc-core.c | 1 + > drivers/hwtracing/coresight/coresight-tmc.h | 17 +++++++++++++++++ > 2 files changed, 18 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c > index be964656be93..4d249af93097 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc-core.c > +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c > @@ -830,6 +830,7 @@ static int __tmc_probe(struct device *dev, struct resource *res) > idr_init(&drvdata->idr); > mutex_init(&drvdata->idr_mutex); > dev_list = &etr_devs; > + INIT_LIST_HEAD(&drvdata->etr_buf_list); > break; > case TMC_CONFIG_TYPE_ETF: > desc.groups = coresight_etf_groups; > diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h > index 6541a27a018e..292e25d82b62 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc.h > +++ b/drivers/hwtracing/coresight/coresight-tmc.h > @@ -208,6 +208,19 @@ struct tmc_resrv_buf { > s64 len; > }; > > +/** > + * @sysfs_buf: Allocated sysfs_buf. > + * @is_free: Indicates whether the buffer is free to choose. > + * @pos: Position of the buffer. > + * @node: Node in etr_buf_list. > + */ > +struct etr_buf_node { > + struct etr_buf *sysfs_buf; > + bool is_free; > + loff_t pos; > + struct list_head node; > +}; > + > /** > * struct tmc_drvdata - specifics associated to an TMC component > * @pclk: APB clock if present, otherwise NULL > @@ -242,6 +255,8 @@ struct tmc_resrv_buf { > * (after crash) by default. > * @crash_mdata: Reserved memory for storing tmc crash metadata. > * Used by ETR/ETF. > + * @etr_buf_list: List that is used to manage allocated etr_buf. > + * @reading_node: Available buffer for byte-cntr reading. > */ > struct tmc_drvdata { > struct clk *pclk; > @@ -271,6 +286,8 @@ struct tmc_drvdata { > struct etr_buf *perf_buf; > struct tmc_resrv_buf resrv_buf; > struct tmc_resrv_buf crash_mdata; > + struct list_head etr_buf_list; > + struct etr_buf_node *reading_node; > }; > > struct etr_buf_operations { > > -- > 2.34.1 > Reviewed-by: Mike Leach <mike.leach(a)linaro.org> -- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK

3 weeks, 3 days

Re: [PATCH v3] coresight: etm3x: Fix cntr_val_show() to match cntr_val_store() behavior

by James Clark

On 02/12/2025 8:26 am, Kuan-Wei Chiu wrote: > The cntr_val_show() function was intended to print the values of all > counters using a loop. However, due to a buffer overwrite issue with > sprintf(), it effectively only displayed the value of the last counter. > > The companion function, cntr_val_store(), allows users to modify a > specific counter selected by 'cntr_idx'. To maintain consistency > between read and write operations and to align with the ETM4x driver > behavior, modify cntr_val_show() to report only the value of the > currently selected counter. > > This change removes the loop and the "counter %d:" prefix, printing > only the hexadecimal value. It also adopts sysfs_emit() for standard > sysfs output formatting. > > Fixes: a939fc5a71ad ("coresight-etm: add CoreSight ETM/PTM driver") > Cc: stable(a)vger.kernel.org > Signed-off-by: Kuan-Wei Chiu <visitorckw(a)gmail.com> > --- > Build test only. > > Changes in v3: > - Switch format specifier to %#x to include the 0x prefix. > - Add Cc stable > > v2: https://lore.kernel.org/lkml/20251201095228.1905489-1-visitorckw@gmail.com/ > > .../hwtracing/coresight/coresight-etm3x-sysfs.c | 15 ++++----------- > 1 file changed, 4 insertions(+), 11 deletions(-) > > diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > index 762109307b86..b3c67e96a82a 100644 > --- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > +++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > @@ -717,26 +717,19 @@ static DEVICE_ATTR_RW(cntr_rld_event); > static ssize_t cntr_val_show(struct device *dev, > struct device_attribute *attr, char *buf) > { > - int i, ret = 0; > u32 val; > struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent); > struct etm_config *config = &drvdata->config; > > if (!coresight_get_mode(drvdata->csdev)) { > spin_lock(&drvdata->spinlock); > - for (i = 0; i < drvdata->nr_cntr; i++) > - ret += sprintf(buf, "counter %d: %x\n", > - i, config->cntr_val[i]); > + val = config->cntr_val[config->cntr_idx]; > spin_unlock(&drvdata->spinlock); > - return ret; > - } > - > - for (i = 0; i < drvdata->nr_cntr; i++) { > - val = etm_readl(drvdata, ETMCNTVRn(i)); > - ret += sprintf(buf, "counter %d: %x\n", i, val); > + } else { > + val = etm_readl(drvdata, ETMCNTVRn(config->cntr_idx)); > } > > - return ret; > + return sysfs_emit(buf, "%#x\n", val); > } > > static ssize_t cntr_val_store(struct device *dev, Reviewed-by: James Clark <james.clark(a)linaro.org>

3 weeks, 4 days

Re: [PATCH v2] coresight: etm3x: Fix cntr_val_show() to match cntr_val_store() behavior

by James Clark

On 01/12/2025 9:52 am, Kuan-Wei Chiu wrote: > The cntr_val_show() function was intended to print the values of all > counters using a loop. However, due to a buffer overwrite issue with > sprintf(), it effectively only displayed the value of the last counter. > > The companion function, cntr_val_store(), allows users to modify a > specific counter selected by 'cntr_idx'. To maintain consistency > between read and write operations and to align with the ETM4x driver > behavior, modify cntr_val_show() to report only the value of the > currently selected counter. > > This change removes the loop and the "counter %d:" prefix, printing > only the hexadecimal value. It also adopts sysfs_emit() for standard > sysfs output formatting. > > Fixes: a939fc5a71ad ("coresight-etm: add CoreSight ETM/PTM driver") > Signed-off-by: Kuan-Wei Chiu <visitorckw(a)gmail.com> > --- > Build test only. > > Changes in v2: > - Redesigned the fix to match cntr_val_store() logic (display only the > currently selected counter) instead of attempting to list all > counters. > - Removed the loop and the "counter %d:" prefix. > - Switched from sprintf() to sysfs_emit(). > - Refactored control flow to use a single return point. > > v1: https://lore.kernel.org/lkml/20251121002350.1166758-1-visitorckw@gmail.com/ > > .../hwtracing/coresight/coresight-etm3x-sysfs.c | 15 ++++----------- > 1 file changed, 4 insertions(+), 11 deletions(-) > > diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > index 762109307b86..a6a650331196 100644 > --- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > +++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c > @@ -717,26 +717,19 @@ static DEVICE_ATTR_RW(cntr_rld_event); > static ssize_t cntr_val_show(struct device *dev, > struct device_attribute *attr, char *buf) > { > - int i, ret = 0; > u32 val; > struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent); > struct etm_config *config = &drvdata->config; > > if (!coresight_get_mode(drvdata->csdev)) { > spin_lock(&drvdata->spinlock); > - for (i = 0; i < drvdata->nr_cntr; i++) > - ret += sprintf(buf, "counter %d: %x\n", > - i, config->cntr_val[i]); > + val = config->cntr_val[config->cntr_idx]; > spin_unlock(&drvdata->spinlock); > - return ret; > - } > - > - for (i = 0; i < drvdata->nr_cntr; i++) { > - val = etm_readl(drvdata, ETMCNTVRn(i)); > - ret += sprintf(buf, "counter %d: %x\n", i, val); > + } else { > + val = etm_readl(drvdata, ETMCNTVRn(config->cntr_idx)); > } > > - return ret; > + return sysfs_emit(buf, "%x\n", val); Sorry I missed this on the previous version, but this should be %#x to add the "0x" prefix. All the other ones in this file have it. Otherwise you can't tell the difference between decimal and hex. > } > > static ssize_t cntr_val_store(struct device *dev,

3 weeks, 5 days

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