[PATCH v7 02/10] Coresight: Add coresight TPDM source driver

Suzuki K Poulose suzuki.poulose at arm.com
Mon May 23 01:57:04 PDT 2022


Hi

On 09/05/2022 14:39, Mao Jinlong wrote:
> Add driver to support Coresight device TPDM (Trace, Profiling and
> Diagnostics Monitor). TPDM is a monitor to collect data from
> different datasets. This change is to add probe/enable/disable
> functions for tpdm source.
> 
> Signed-off-by: Tao Zhang <quic_taozha at quicinc.com>
> Signed-off-by: Mao Jinlong <quic_jinlmao at quicinc.com>
> ---
>   drivers/hwtracing/coresight/Kconfig          |  13 ++
>   drivers/hwtracing/coresight/Makefile         |   1 +
>   drivers/hwtracing/coresight/coresight-core.c |   5 +-
>   drivers/hwtracing/coresight/coresight-tpdm.c | 146 +++++++++++++++++++
>   drivers/hwtracing/coresight/coresight-tpdm.h |  26 ++++
>   include/linux/coresight.h                    |   1 +
>   6 files changed, 191 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/hwtracing/coresight/coresight-tpdm.c
>   create mode 100644 drivers/hwtracing/coresight/coresight-tpdm.h
> 
> diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
> index 514a9b8086e3..5c506a1cd08f 100644
> --- a/drivers/hwtracing/coresight/Kconfig
> +++ b/drivers/hwtracing/coresight/Kconfig
> @@ -201,4 +201,17 @@ config CORESIGHT_TRBE
>   
>   	  To compile this driver as a module, choose M here: the module will be
>   	  called coresight-trbe.
> +
> +config CORESIGHT_TPDM
> +	tristate "CoreSight Trace, Profiling & Diagnostics Monitor driver"
> +	select CORESIGHT_LINKS_AND_SINKS
> +	help
> +	  This driver provides support for configuring monitor. Monitors are
> +	  primarily responsible for data set collection and support the
> +	  ability to collect any permutation of data set types. Monitors are
> +	  also responsible for interaction with system cross triggering.

I find the last statement a bit confusing. Could this be :

	"Monitors are also connected to the cross triggers."

> +
> +	  To compile this driver as a module, choose M here: the module will be
> +	  called coresight-tpdm.
> +
>   endif
> diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
> index 329a0c704b87..6bb9b1746bc7 100644
> --- a/drivers/hwtracing/coresight/Makefile
> +++ b/drivers/hwtracing/coresight/Makefile
> @@ -25,5 +25,6 @@ obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o
>   obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.o
>   obj-$(CONFIG_CORESIGHT_CTI) += coresight-cti.o
>   obj-$(CONFIG_CORESIGHT_TRBE) += coresight-trbe.o
> +obj-$(CONFIG_CORESIGHT_TPDM) += coresight-tpdm.o
>   coresight-cti-y := coresight-cti-core.o	coresight-cti-platform.o \
>   		   coresight-cti-sysfs.o
> diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> index 23ab16dd9b5d..75fe1781df20 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -1047,7 +1047,8 @@ static int coresight_validate_source(struct coresight_device *csdev,
>   	}
>   
>   	if (subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_PROC &&
> -	    subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE) {
> +	    subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE &&
> +	    subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_DATA_ONLY) {
>   		dev_err(&csdev->dev, "wrong device subtype in %s\n", function);
>   		return -EINVAL;
>   	}
> @@ -1116,6 +1117,7 @@ int coresight_enable(struct coresight_device *csdev)
>   		per_cpu(tracer_path, cpu) = path;
>   		break;
>   	case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
> +	case CORESIGHT_DEV_SUBTYPE_SOURCE_DATA_ONLY:
>   		/*
>   		 * Use the hash of source's device name as ID
>   		 * and map the ID to the pointer of the path.
> @@ -1165,6 +1167,7 @@ void coresight_disable(struct coresight_device *csdev)
>   		per_cpu(tracer_path, cpu) = NULL;
>   		break;
>   	case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
> +	case CORESIGHT_DEV_SUBTYPE_SOURCE_DATA_ONLY:
>   		hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
>   		/* Find the path by the hash. */
>   		path = idr_find(&path_idr, hash);
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
> new file mode 100644
> index 000000000000..6a4e2a35053d
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
> @@ -0,0 +1,146 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#include <linux/amba/bus.h>
> +#include <linux/bitmap.h>
> +#include <linux/coresight.h>
> +#include <linux/coresight-pmu.h>
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/fs.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +
> +#include "coresight-priv.h"
> +#include "coresight-tpdm.h"
> +
> +DEFINE_CORESIGHT_DEVLIST(tpdm_devs, "tpdm");
> +
> +/* TPDM enable operations */
> +static int tpdm_enable(struct coresight_device *csdev,
> +		       struct perf_event *event, u32 mode)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> +
> +	mutex_lock(&drvdata->lock);
> +	if (drvdata->enable) {
> +		mutex_unlock(&drvdata->lock);
> +		return -EBUSY;
> +	}
> +
> +	drvdata->enable = true;
> +	mutex_unlock(&drvdata->lock);
> +
> +	dev_info(drvdata->dev, "TPDM tracing enabled\n");
> +	return 0;
> +}
> +
> +/* TPDM disable operations */
> +static void tpdm_disable(struct coresight_device *csdev,
> +			 struct perf_event *event)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> +
> +	mutex_lock(&drvdata->lock);
> +	if (!drvdata->enable) {
> +		mutex_unlock(&drvdata->lock);
> +		return;
> +	}
> +
> +	drvdata->enable = false;
> +	mutex_unlock(&drvdata->lock);
> +
> +	dev_info(drvdata->dev, "TPDM tracing disabled\n");
> +}
> +
> +static const struct coresight_ops_source tpdm_source_ops = {
> +	.enable		= tpdm_enable,
> +	.disable	= tpdm_disable,
> +};
> +
> +static const struct coresight_ops tpdm_cs_ops = {
> +	.source_ops	= &tpdm_source_ops,
> +};
> +
> +static int tpdm_probe(struct amba_device *adev, const struct amba_id *id)
> +{
> +	struct device *dev = &adev->dev;
> +	struct coresight_platform_data *pdata;
> +	struct tpdm_drvdata *drvdata;
> +	struct coresight_desc desc = { 0 };
> +
> +	pdata = coresight_get_platform_data(dev);
> +	if (IS_ERR(pdata))
> +		return PTR_ERR(pdata);
> +	adev->dev.platform_data = pdata;
> +
> +	/* driver data*/
> +	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
> +	if (!drvdata)
> +		return -ENOMEM;
> +	drvdata->dev = &adev->dev;
> +	dev_set_drvdata(dev, drvdata);
> +
> +	drvdata->base = devm_ioremap_resource(dev, &adev->res);
> +	if (!drvdata->base)
> +		return -ENOMEM;
> +
> +	mutex_init(&drvdata->lock);
> +
> +	/* Set up coresight component description */
> +	desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
> +	if (!desc.name)
> +		return -ENOMEM;
> +	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
> +	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_DATA_ONLY;
> +	desc.ops = &tpdm_cs_ops;
> +	desc.pdata = adev->dev.platform_data;
> +	desc.dev = &adev->dev;

desc.access must be initialised here.

	desc.access = CSDEV_ACCESS_IOMEM(drvdata->base);

> +	drvdata->csdev = coresight_register(&desc);
> +	if (IS_ERR(drvdata->csdev))
> +		return PTR_ERR(drvdata->csdev);
> +
> +	/* Decrease pm refcount when probe is done.*/
> +	pm_runtime_put(&adev->dev);
> +
> +	return 0;
> +}
> +
> +static void __exit tpdm_remove(struct amba_device *adev)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
> +
> +	coresight_unregister(drvdata->csdev);
> +}
> +
> +/*
> + * Different TPDM has different periph id.
> + * The difference is 0-7 bits' value. So ignore 0-7 bits.
> + */
> +static struct amba_id tpdm_ids[] = {
> +	{
> +		.id = 0x000f0e00,
> +		.mask = 0x000fff00,
> +	},
> +	{ 0, 0},
> +};
> +
> +static struct amba_driver tpdm_driver = {
> +	.drv = {
> +		.name   = "coresight-tpdm",
> +		.owner	= THIS_MODULE,
> +		.suppress_bind_attrs = true,
> +	},
> +	.probe          = tpdm_probe,
> +	.id_table	= tpdm_ids,
> +	.remove		= tpdm_remove,
> +};
> +
> +module_amba_driver(tpdm_driver);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("Trace, Profiling & Diagnostic Monitor driver");
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h b/drivers/hwtracing/coresight/coresight-tpdm.h
> new file mode 100644
> index 000000000000..94a7748a5426
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.h
> @@ -0,0 +1,26 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#ifndef _CORESIGHT_CORESIGHT_TPDM_H
> +#define _CORESIGHT_CORESIGHT_TPDM_H
> +
> +/**
> + * struct tpdm_drvdata - specifics associated to an TPDM component
> + * @base:       memory mapped base address for this component.
> + * @dev:        The device entity associated to this component.
> + * @csdev:      component vitals needed by the framework.
> + * @lock:       lock for the enable value.
> + * @enable:     enable status of the component.
> + */
> +
> +struct tpdm_drvdata {
> +	void __iomem		*base;
> +	struct device		*dev;
> +	struct coresight_device	*csdev;
> +	struct mutex		lock;

Why mutex lock ? Couldn't this be a spinlock ?

> +	bool			enable;
> +};
> +
> +#endif  /* _CORESIGHT_CORESIGHT_TPDM_H */
> diff --git a/include/linux/coresight.h b/include/linux/coresight.h
> index 247147c11231..a9efac55029d 100644
> --- a/include/linux/coresight.h
> +++ b/include/linux/coresight.h
> @@ -61,6 +61,7 @@ enum coresight_dev_subtype_source {
>   	CORESIGHT_DEV_SUBTYPE_SOURCE_PROC,
>   	CORESIGHT_DEV_SUBTYPE_SOURCE_BUS,
>   	CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE,
> +	CORESIGHT_DEV_SUBTYPE_SOURCE_DATA_ONLY,

super minor nit: I find the choice of name a bit odd.
We could simply make it something like :

	CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS:

Suzuki

>   };
>   
>   enum coresight_dev_subtype_helper {




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