Introduction of Coresight Dummy subunit
The Coresight Dummy subunit is for Coresight Dummy component, there are some
specific Coresight devices that HLOS don't have permission to access. Such as
some TPDMs, they would be configured in NON-HLOS side, but it's necessary to
build Coresight path for it to debug. So there need driver to register dummy
devices as Coresight devices.
Commit link:
https://git.codelinaro.org/clo/linux-kernel/coresight/-/tree/coresight-dummy
Hao Zhang (3):
Coresight: Add coresight dummy driver
dt-bindings: arm: Add Coresight Dummy Trace YAML schema
Documentation: trace: Add documentation for Coresight Dummy Trace
.../bindings/arm/qcom,coresight-dummy.yaml | 129 +++++++++++++
.../trace/coresight/coresight-dummy.rst | 58 ++++++
drivers/hwtracing/coresight/Kconfig | 11 ++
drivers/hwtracing/coresight/Makefile | 1 +
drivers/hwtracing/coresight/coresight-dummy.c | 176 ++++++++++++++++++
5 files changed, 375 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml
create mode 100644 Documentation/trace/coresight/coresight-dummy.rst
create mode 100644 drivers/hwtracing/coresight/coresight-dummy.c
--
2.17.1
Some Coresight devices that HLOS don't have permission to access
or configure. Such as Coresight sink EUD, some TPDMs etc. So there
need driver to register dummy devices as Coresight devices. Provide
Coresight API for dummy device operations, such as enabling and
disabling dummy devices. Build the Coresight path for dummy sink or
dummy source for debugging.
Signed-off-by: Hao Zhang <[email protected]>
---
drivers/hwtracing/coresight/Kconfig | 11 ++
drivers/hwtracing/coresight/Makefile | 1 +
drivers/hwtracing/coresight/coresight-dummy.c | 176 ++++++++++++++++++
3 files changed, 188 insertions(+)
create mode 100644 drivers/hwtracing/coresight/coresight-dummy.c
diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 2b5bbfffbc4f..06f0a7594169 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -236,4 +236,15 @@ config CORESIGHT_TPDA
To compile this driver as a module, choose M here: the module will be
called coresight-tpda.
+
+config CORESIGHT_DUMMY
+ tristate "Dummy driver support"
+ help
+ Enables support for dummy driver. Dummy driver can be used for
+ CoreSight sources/sinks that are owned and configured by some
+ other subsystem and use Linux drivers to configure rest of trace
+ path.
+
+ To compile this driver as a module, choose M here: the module will be
+ called coresight-dummy.
endif
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 33bcc3f7b8ae..995d3b2c76df 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -30,3 +30,4 @@ obj-$(CONFIG_CORESIGHT_TPDA) += coresight-tpda.o
coresight-cti-y := coresight-cti-core.o coresight-cti-platform.o \
coresight-cti-sysfs.o
obj-$(CONFIG_ULTRASOC_SMB) += ultrasoc-smb.o
+obj-$(CONFIG_CORESIGHT_DUMMY) += coresight-dummy.o
diff --git a/drivers/hwtracing/coresight/coresight-dummy.c b/drivers/hwtracing/coresight/coresight-dummy.c
new file mode 100644
index 000000000000..d06baafb77da
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-dummy.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/coresight.h>
+#include <linux/of.h>
+#include <linux/pm_runtime.h>
+
+#include "coresight-priv.h"
+#include "coresight-trace-id.h"
+
+struct dummy_drvdata {
+ struct device *dev;
+ struct coresight_device *csdev;
+ int traceid;
+};
+
+DEFINE_CORESIGHT_DEVLIST(dummy_devs, "dummy");
+
+static int dummy_source_enable(struct coresight_device *csdev,
+ struct perf_event *event, u32 mode)
+{
+ struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ dev_info(drvdata->dev, "Dummy source enabled\n");
+
+ return 0;
+}
+
+static void dummy_source_disable(struct coresight_device *csdev,
+ struct perf_event *event)
+{
+ struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ dev_info(drvdata->dev, "Dummy source disabled\n");
+}
+
+static int dummy_sink_enable(struct coresight_device *csdev, u32 mode,
+ void *data)
+{
+ struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ dev_info(drvdata->dev, "Dummy sink enabled\n");
+
+ return 0;
+}
+
+static int dummy_sink_disable(struct coresight_device *csdev)
+{
+ struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+ dev_info(drvdata->dev, "Dummy sink disabled\n");
+
+ return 0;
+}
+
+static const struct coresight_ops_source dummy_source_ops = {
+ .enable = dummy_source_enable,
+ .disable = dummy_source_disable,
+};
+
+static const struct coresight_ops_sink dummy_sink_ops = {
+ .enable = dummy_sink_enable,
+ .disable = dummy_sink_disable,
+};
+
+static const struct coresight_ops dummy_cs_ops = {
+ .source_ops = &dummy_source_ops,
+ .sink_ops = &dummy_sink_ops,
+};
+
+static int dummy_probe(struct platform_device *pdev)
+{
+ int ret, trace_id;
+ struct device *dev = &pdev->dev;
+ struct coresight_platform_data *pdata;
+ struct dummy_drvdata *drvdata;
+ struct coresight_desc desc = { 0 };
+
+ desc.name = coresight_alloc_device_name(&dummy_devs, dev);
+ if (!desc.name)
+ return -ENOMEM;
+
+ pdata = coresight_get_platform_data(dev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+ pdev->dev.platform_data = pdata;
+
+ drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+ if (!drvdata)
+ return -ENOMEM;
+
+ drvdata->dev = &pdev->dev;
+ platform_set_drvdata(pdev, drvdata);
+
+ if (of_property_read_bool(pdev->dev.of_node, "qcom,dummy-source")) {
+ desc.type = CORESIGHT_DEV_TYPE_SOURCE;
+ desc.subtype.source_subtype =
+ CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS;
+ } else if (of_property_read_bool(pdev->dev.of_node,
+ "qcom,dummy-sink")) {
+ desc.type = CORESIGHT_DEV_TYPE_SINK;
+ desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
+ } else {
+ dev_info(dev, "Device type not set\n");
+ return -EINVAL;
+ }
+
+ desc.ops = &dummy_cs_ops;
+ desc.pdata = pdev->dev.platform_data;
+ desc.dev = &pdev->dev;
+ drvdata->csdev = coresight_register(&desc);
+ if (IS_ERR(drvdata->csdev))
+ return PTR_ERR(drvdata->csdev);
+
+ trace_id = coresight_trace_id_get_system_id();
+ if (trace_id < 0) {
+ ret = trace_id;
+ goto cs_unregister;
+ }
+ drvdata->traceid = (u8)trace_id;
+
+ pm_runtime_enable(dev);
+ dev_info(dev, "Dummy device initialized\n");
+
+ return 0;
+
+cs_unregister:
+ coresight_unregister(drvdata->csdev);
+
+ return ret;
+}
+
+static int dummy_remove(struct platform_device *pdev)
+{
+ struct dummy_drvdata *drvdata = platform_get_drvdata(pdev);
+ struct device *dev = &pdev->dev;
+
+ coresight_trace_id_put_system_id(drvdata->traceid);
+ pm_runtime_disable(dev);
+ coresight_unregister(drvdata->csdev);
+ return 0;
+}
+
+static const struct of_device_id dummy_match[] = {
+ {.compatible = "qcom,coresight-dummy"},
+ {},
+};
+
+static struct platform_driver dummy_driver = {
+ .probe = dummy_probe,
+ .remove = dummy_remove,
+ .driver = {
+ .name = "coresight-dummy",
+ .of_match_table = dummy_match,
+ },
+};
+
+int __init dummy_init(void)
+{
+ return platform_driver_register(&dummy_driver);
+}
+module_init(dummy_init);
+
+void __exit dummy_exit(void)
+{
+ platform_driver_unregister(&dummy_driver);
+}
+module_exit(dummy_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CoreSight dummy source driver");
--
2.17.1
Hi Hao,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on robh/for-next]
[also build test WARNING on linus/master v6.3-rc2 next-20230316]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Hao-Zhang/Coresight-Add-coresight-dummy-driver/20230316-112827
base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
patch link: https://lore.kernel.org/r/20230316032005.6509-2-quic_hazha%40quicinc.com
patch subject: [PATCH v1 1/3] Coresight: Add coresight dummy driver
config: arm-allyesconfig (https://download.01.org/0day-ci/archive/20230316/[email protected]/config)
compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/140cd28ed9031020826cfb5e62e80e28f7504895
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Hao-Zhang/Coresight-Add-coresight-dummy-driver/20230316-112827
git checkout 140cd28ed9031020826cfb5e62e80e28f7504895
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/hwtracing/coresight/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
| Link: https://lore.kernel.org/oe-kbuild-all/[email protected]/
All warnings (new ones prefixed by >>):
>> drivers/hwtracing/coresight/coresight-dummy.c:163:12: warning: no previous prototype for 'dummy_init' [-Wmissing-prototypes]
163 | int __init dummy_init(void)
| ^~~~~~~~~~
>> drivers/hwtracing/coresight/coresight-dummy.c:169:13: warning: no previous prototype for 'dummy_exit' [-Wmissing-prototypes]
169 | void __exit dummy_exit(void)
| ^~~~~~~~~~
vim +/dummy_init +163 drivers/hwtracing/coresight/coresight-dummy.c
162
> 163 int __init dummy_init(void)
164 {
165 return platform_driver_register(&dummy_driver);
166 }
167 module_init(dummy_init);
168
> 169 void __exit dummy_exit(void)
170 {
171 platform_driver_unregister(&dummy_driver);
172 }
173 module_exit(dummy_exit);
174
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
On 16/03/2023 03:20, Hao Zhang wrote:
> Introduction of Coresight Dummy subunit
> The Coresight Dummy subunit is for Coresight Dummy component, there are some
> specific Coresight devices that HLOS don't have permission to access. Such as
What is HLOS ?
> some TPDMs, they would be configured in NON-HLOS side, but it's necessary to
What is NON-HLOS ?
> build Coresight path for it to debug. So there need driver to register dummy
> devices as Coresight devices.
Build a path for who to debug ? If this is used by some privileged
software, shouldn't that do all of the work ?
Suzuki
>
> Commit link:
> https://git.codelinaro.org/clo/linux-kernel/coresight/-/tree/coresight-dummy
>
> Hao Zhang (3):
> Coresight: Add coresight dummy driver
> dt-bindings: arm: Add Coresight Dummy Trace YAML schema
> Documentation: trace: Add documentation for Coresight Dummy Trace
>
> .../bindings/arm/qcom,coresight-dummy.yaml | 129 +++++++++++++
> .../trace/coresight/coresight-dummy.rst | 58 ++++++
> drivers/hwtracing/coresight/Kconfig | 11 ++
> drivers/hwtracing/coresight/Makefile | 1 +
> drivers/hwtracing/coresight/coresight-dummy.c | 176 ++++++++++++++++++
> 5 files changed, 375 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml
> create mode 100644 Documentation/trace/coresight/coresight-dummy.rst
> create mode 100644 drivers/hwtracing/coresight/coresight-dummy.c
>
Hi Suzuki,
On 3/16/2023 6:55 PM, Suzuki K Poulose wrote:
> On 16/03/2023 03:20, Hao Zhang wrote:
>> Introduction of Coresight Dummy subunit
>> The Coresight Dummy subunit is for Coresight Dummy component, there
>> are some
>> specific Coresight devices that HLOS don't have permission to access.
>> Such as
>
> What is HLOS ?
The term HLOS stands for High Level OS, it means linux in this case. The
HLOS runs on APPS processor.
>> some TPDMs, they would be configured in NON-HLOS side, but it's
>> necessary to
>
> What is NON-HLOS ?
There are some other sub-processors like modem, adsp etc, they do not
have a High Level OS. The OS in these sub-processors is lightweight,
less powerful, somewhat real-time, it would be called NON-HLOS.
>> build Coresight path for it to debug. So there need driver to register
>> dummy
>> devices as Coresight devices.
>
> Build a path for who to debug ? If this is used by some privileged
> software, shouldn't that do all of the work ?
>
> Suzuki
There is coresight source or sink in sub-processor, it would be
configured by NON-HLOS, and need HLOS to configure the last coresight
components. So we will use dummy source or sink to replace it in HLOS
side for building the whole path(from source to sink).
Thanks,
Hao
>>
>> Commit link:
>> https://git.codelinaro.org/clo/linux-kernel/coresight/-/tree/coresight-dummy
>>
>> Hao Zhang (3):
>> Coresight: Add coresight dummy driver
>> dt-bindings: arm: Add Coresight Dummy Trace YAML schema
>> Documentation: trace: Add documentation for Coresight Dummy Trace
>>
>> .../bindings/arm/qcom,coresight-dummy.yaml | 129 +++++++++++++
>> .../trace/coresight/coresight-dummy.rst | 58 ++++++
>> drivers/hwtracing/coresight/Kconfig | 11 ++
>> drivers/hwtracing/coresight/Makefile | 1 +
>> drivers/hwtracing/coresight/coresight-dummy.c | 176 ++++++++++++++++++
>> 5 files changed, 375 insertions(+)
>> create mode 100644
>> Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml
>> create mode 100644 Documentation/trace/coresight/coresight-dummy.rst
>> create mode 100644 drivers/hwtracing/coresight/coresight-dummy.c
>>
>