The specific config field that an event format attribute is in is
consistently hard coded, even though the API is supposed to be that the
driver publishes the config field name. To stop this pattern from being
copy pasted and causing problems in the future, replace them all with
calls to a new helper that returns the value that a user set.
This reveals some issues in evsel__set_config_if_unset(). It doesn't
work with sparse bitfields, which are an unused but documented feature.
And it also only writes to the attr.config field. To fix it we need to
start tracking user changes for all config fields and then use existing
helper functions that support sparse bitfields. Some other refactoring
was also required and a test was added.
---
Changes in v4:
- Constify some function args (Ian)
- Move some evsel__* functions to evsel.c and make some pmu.c functions
public to support this (Ian)
- Drop pmu arg where it can be fetched from evsel->pmu (Ian)
- Link to v3: https://lore.kernel.org/r/20251212-james-perf-config-bits-v3-0-aa36a4846776…
Changes in v3:
- Fix uninitialized variable warning on GCC
- Fix leak of evlist in test
- Confirm no type punning issues with ubsan (Ian)
- Link to v2: https://lore.kernel.org/r/20251208-james-perf-config-bits-v2-0-4ac0281993b0…
Changes in v2:
- Remove macros in get_config_chgs() and some other refactoring.
- Support sparse bitfields in evsel__set_config_if_unset().
- Always track user changes instead of only when
'pmu->perf_event_attr_init_default' is set.
- Add a test.
- Don't bail out in cs-etm.c if any format fields are missing (Leo).
- Rename 'guess' to 'synth' (Mike).
- Link to v1: https://lore.kernel.org/r/20251201-james-perf-config-bits-v1-0-22ecbbf8007c…
---
James Clark (14):
perf parse-events: Refactor get_config_terms() to remove macros
perf evsel: Refactor evsel__set_config_if_unset() arguments
perf evsel: Move evsel__* functions to evsel.c
perf evsel: Support sparse fields in evsel__set_config_if_unset()
perf parse-events: Track all user changed config bits
perf evsel: apply evsel__set_config_if_unset() to all config fields
perf evsel: Add a helper to get the value of a config field
perf parse-events: Always track user config changes
perf tests: Test evsel__set_config_if_unset() and config change tracking
perf cs-etm: Make a helper to find the Coresight evsel
perf cs-etm: Don't use hard coded config bits when setting up ETMCR
perf cs-etm: Don't use hard coded config bits when setting up TRCCONFIGR
perf cs-etm: Don't hard code config attribute when configuring the event
perf arm-spe: Don't hard code config attribute
tools/perf/arch/arm/util/cs-etm.c | 201 +++++++++++++++-------------
tools/perf/arch/arm64/util/arm-spe.c | 17 +--
tools/perf/arch/x86/util/intel-pt.c | 3 +-
tools/perf/tests/pmu.c | 91 +++++++++++++
tools/perf/util/evsel.c | 112 +++++++++++++++-
tools/perf/util/evsel.h | 6 +-
tools/perf/util/evsel_config.h | 7 +-
tools/perf/util/parse-events.c | 248 ++++++++++++++++++++---------------
tools/perf/util/pmu.c | 95 ++++----------
tools/perf/util/pmu.h | 34 ++++-
10 files changed, 529 insertions(+), 285 deletions(-)
---
base-commit: cbd41c6d4c26c161a2b0e70ad411d3885ff13507
change-id: 20251112-james-perf-config-bits-bee7106f0f00
Best regards,
--
James Clark <james.clark(a)linaro.org>
On Mon, 03 Nov 2025 15:06:20 +0800, Jie Gan wrote:
> Enable CTCU device for QCS8300 platform. Add a fallback mechnasim in binding to utilize
> the compitable of the SA8775p platform becuase the CTCU for QCS8300 shares same
> configurations as SA8775p platform.
>
> Changes in V4:
> 1. dtsi file has been renamed from qcs8300.dtsi -> monaco.dtsi
> Link to V3 - https://lore.kernel.org/all/20251013-enable-ctcu-for-qcs8300-v3-0-611e6e0d3…
>
> [...]
Applied, thanks!
[1/2] dt-bindings: arm: add CTCU device for monaco
https://git.kernel.org/coresight/c/51cd1fb70e08
Best regards,
--
Suzuki K Poulose <suzuki.poulose(a)arm.com>
Hi,
On Fri, Dec 19, 2025 at 10:39:49AM +0800, Ma Ke wrote:
[...]
> From the discussion, I note two possible fix directions:
>
> 1. Release the initial reference in etm_setup_aux() (current v2 patch)
> 2. Modify the behavior of coresight_get_sink_by_id() itself so it
> doesn't increase the reference count.
The option 2 is the right way to go.
> To ensure the correctness of the v3 patch, I'd like to confirm which
> patch is preferred. If option 2 is the consensus, I'm happy to modify
> the implementation of coresight_get_sink_by_id() as suggested.
It is good to use a separate patch to fix
coresight_find_device_by_fwnode() mentioned by James:
diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
index 0db64c5f4995..2b34f818ba88 100644
--- a/drivers/hwtracing/coresight/coresight-platform.c
+++ b/drivers/hwtracing/coresight/coresight-platform.c
@@ -107,14 +107,16 @@ coresight_find_device_by_fwnode(struct fwnode_handle *fwnode)
* platform bus.
*/
dev = bus_find_device_by_fwnode(&platform_bus_type, fwnode);
- if (dev)
- return dev;
/*
* We have a configurable component - circle through the AMBA bus
* looking for the device that matches the endpoint node.
*/
- return bus_find_device_by_fwnode(&amba_bustype, fwnode);
+ if (!dev)
+ dev = bus_find_device_by_fwnode(&amba_bustype, fwnode);
+
+ put_device(dev);
+ return dev;
}
/*
@@ -274,7 +276,6 @@ static int of_coresight_parse_endpoint(struct device *dev,
of_node_put(rparent);
of_node_put(rep);
- put_device(rdev);
return ret;
}
Thanks for working on this.
On 19/12/2025 09:08, Jie Gan wrote:
>
>
> On 11/3/2025 3:06 PM, Jie Gan wrote:
>> The CTCU device for monaco shares the same configurations as SA8775p. Add
>> a fallback to enable the CTCU for monaco to utilize the compitable of the
>> SA8775p.
>>
>
> Gentle reminder.
I was under the assumption that this was going via msm tree ? Sorry, I
misunderstood. I can pull this in for v6.20
Suzuki
>
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski(a)linaro.org>
>> Acked-by: Suzuki K Poulose <suzuki.poulose(a)arm.com>
>> Reviewed-by: Bjorn Andersson <andersson(a)kernel.org>
>> Signed-off-by: Jie Gan <jie.gan(a)oss.qualcomm.com>
>> ---
>> Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml | 9 +
>> ++++++--
>> 1 file changed, 7 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-
>> ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-
>> ctcu.yaml
>> index c969c16c21ef..460f38ddbd73 100644
>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
>> @@ -26,8 +26,13 @@ description: |
>> properties:
>> compatible:
>> - enum:
>> - - qcom,sa8775p-ctcu
>> + oneOf:
>> + - items:
>> + - enum:
>> + - qcom,qcs8300-ctcu
>> + - const: qcom,sa8775p-ctcu
>> + - enum:
>> + - qcom,sa8775p-ctcu
>> reg:
>> maxItems: 1
>>
>
This patch series adds support for CoreSight components local to CPU clusters,
including funnel, replicator, and TMC, which reside within CPU cluster power
domains. These components require special handling due to power domain
constraints.
Unlike system-level CoreSight devices, these components share the CPU cluster's
power domain. When the cluster enters low-power mode (LPM), their registers
become inaccessible. Notably, `pm_runtime_get` alone cannot bring the cluster
out of LPM, making standard register access unreliable.
To address this, the series introduces:
- Identifying cluster-bound devices via a new `qcom,cpu-bound-components`
device tree property.
- Implementing deferred probing: if associated CPUs are offline during
probe, initialization is deferred until a CPU hotplug notifier detects
the CPU coming online.
- Utilizing `smp_call_function_single()` to ensure register accesses
(initialization, enablement, sysfs reads) are always executed on a
powered CPU within the target cluster.
- Extending the CoreSight link `enable` callback to pass the `cs_mode`.
This allows drivers to distinguish between SysFS and Perf modes and
apply mode-specific logic.
Jie Gan (1):
arm64: dts: qcom: hamoa: add Coresight nodes for APSS debug block
Yuanfang Zhang (11):
dt-bindings: arm: coresight: Add 'qcom,cpu-bound-components' property
coresight: Pass trace mode to link enable callback
coresight-funnel: Support CPU cluster funnel initialization
coresight-funnel: Defer probe when associated CPUs are offline
coresight-replicator: Support CPU cluster replicator initialization
coresight-replicator: Defer probe when associated CPUs are offline
coresight-replicator: Update management interface for CPU-bound devices
coresight-tmc: Support probe and initialization for CPU cluster TMCs
coresight-tmc-etf: Refactor enable function for CPU cluster ETF support
coresight-tmc: Update management interface for CPU-bound TMCs
coresight-tmc: Defer probe when associated CPUs are offline
Verification:
This series has been verified on sm8750.
Test steps for delay probe:
1. limit the system to enable at most 6 CPU cores during boot.
2. echo 1 >/sys/bus/cpu/devices/cpu6/online.
3. check whether ETM6 and ETM7 have been probed.
Test steps for sysfs mode:
echo 1 >/sys/bus/coresight/devices/tmc_etf0/enable_sink
echo 1 >/sys/bus/coresight/devices/etm0/enable_source
echo 1 >/sys/bus/coresight/devices/etm6/enable_source
echo 0 >/sys/bus/coresight/devices/etm0/enable_source
echo 0 >/sys/bus/coresight/devicse/etm6/enable_source
echo 0 >/sys/bus/coresight/devices/tmc_etf0/enable_sink
echo 1 >/sys/bus/coresight/devices/tmc_etf1/enable_sink
echo 1 >/sys/bus/coresight/devcies/etm0/enable_source
cat /dev/tmc_etf1 >/tmp/etf1.bin
echo 0 >/sys/bus/coresight/devices/etm0/enable_source
echo 0 >/sys/bus/coresight/devices/tmc_etf1/enable_sink
echo 1 >/sys/bus/coresight/devices/tmc_etf2/enable_sink
echo 1 >/sys/bus/coresight/devices/etm6/enable_source
cat /dev/tmc_etf2 >/tmp/etf2.bin
echo 0 >/sys/bus/coresight/devices/etm6/enable_source
echo 0 >/sys/bus/coresight/devices/tmc_etf2/enable_sink
Test steps for sysfs node:
cat /sys/bus/coresight/devices/tmc_etf*/mgmt/*
cat /sys/bus/coresight/devices/funnel*/funnel_ctrl
cat /sys/bus/coresight/devices/replicator*/mgmt/*
Test steps for perf mode:
perf record -a -e cs_etm//k -- sleep 5
Signed-off-by: Yuanfang Zhang <yuanfang.zhang(a)oss.qualcomm.com>
---
Changes in v2:
- Use the qcom,cpu-bound-components device tree property to identify devices
bound to a cluster.
- Refactor commit message.
- Introduce a supported_cpus field in the drvdata structure to record the CPUs
that belong to the cluster where the local component resides.
- Link to v1: https://lore.kernel.org/r/20251027-cpu_cluster_component_pm-v1-0-31355ac588…
---
Jie Gan (1):
arm64: dts: qcom: hamoa: Add CoreSight nodes for APSS debug block
Yuanfang Zhang (11):
dt-bindings: arm: coresight: Add 'qcom,cpu-bound-components' property
coresight-funnel: Support CPU cluster funnel initialization
coresight-funnel: Defer probe when associated CPUs are offline
coresight-replicator: Support CPU cluster replicator initialization
coresight-replicator: Defer probe when associated CPUs are offline
coresight-replicator: Update management interface for CPU-bound devices
coresight-tmc: Support probe and initialization for CPU cluster TMCs
coresight-tmc-etf: Refactor enable function for CPU cluster ETF support
coresight-tmc: Update management interface for CPU-bound TMCs
coresight-tmc: Defer probe when associated CPUs are offline
coresight: Pass trace mode to link enable callback
.../bindings/arm/arm,coresight-dynamic-funnel.yaml | 5 +
.../arm/arm,coresight-dynamic-replicator.yaml | 5 +
.../devicetree/bindings/arm/arm,coresight-tmc.yaml | 5 +
arch/arm64/boot/dts/qcom/hamoa.dtsi | 926 +++++++++++++++++++++
arch/arm64/boot/dts/qcom/purwa.dtsi | 12 +
drivers/hwtracing/coresight/coresight-core.c | 7 +-
drivers/hwtracing/coresight/coresight-funnel.c | 258 +++++-
drivers/hwtracing/coresight/coresight-replicator.c | 341 +++++++-
drivers/hwtracing/coresight/coresight-tmc-core.c | 387 +++++++--
drivers/hwtracing/coresight/coresight-tmc-etf.c | 106 ++-
drivers/hwtracing/coresight/coresight-tmc.h | 10 +
drivers/hwtracing/coresight/coresight-tnoc.c | 3 +-
drivers/hwtracing/coresight/coresight-tpda.c | 3 +-
include/linux/coresight.h | 3 +-
14 files changed, 1902 insertions(+), 169 deletions(-)
---
base-commit: 008d3547aae5bc86fac3eda317489169c3fda112
change-id: 20251016-cpu_cluster_component_pm-ce518f510433
Best regards,
--
Yuanfang Zhang <yuanfang.zhang(a)oss.qualcomm.com>