Re: [PATCH v2 2/9] Coresight: Add coresight TPDM source driver

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On Thu, Dec 09, 2021 at 10:15:36PM +0800, 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@quicinc.com>
> Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
> ---
>  MAINTAINERS                                  |   8 +
>  drivers/hwtracing/coresight/Kconfig          |  13 ++
>  drivers/hwtracing/coresight/Makefile         |   1 +
>  drivers/hwtracing/coresight/coresight-core.c |   3 +-
>  drivers/hwtracing/coresight/coresight-tpdm.c | 152 +++++++++++++++++++
>  drivers/hwtracing/coresight/coresight-tpdm.h |  31 ++++
>  include/linux/coresight.h                    |   1 +
>  7 files changed, 208 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/hwtracing/coresight/coresight-tpdm.c
>  create mode 100644 drivers/hwtracing/coresight/coresight-tpdm.h
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7a2345ce8521..59f39b3194f6 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -15560,6 +15560,14 @@ L:	netdev@vger.kernel.org
>  S:	Supported
>  F:	drivers/net/ipa/
>  
> +QCOM CORESIGHT COMPONENTS DRIVER
> +M:	Tao Zhang <quic_taozha@quicinc.com>
> +M:	Jinlong Mao <quic_jinlmao@quicinc.com>
> +M:	Mathieu Poirier <mathieu.poirier@linaro.org>
> +M:	Suzuki K Poulose <suzuki.poulose@arm.com>
> +S:	Maintained
> +F:	drivers/hwtracing/coresight/coresight-tpdm.c
> +

There is no need for an extra entry in the MAINTAINERS file.  The checkpatch.pl
script is smart enough to know when to CC you and Tao every time the TPDM/TPDA
drivers are modified.  Suzuki and I will simply wait for you guys to add your RB
tags before reviewing the patches.  I have explained this in the previous revision. 

>  QEMU MACHINE EMULATOR AND VIRTUALIZER SUPPORT
>  M:	Gabriel Somlo <somlo@cmu.edu>
>  M:	"Michael S. Tsirkin" <mst@redhat.com>
> 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

Is this available on 32bit HW as well?  If not please make it dependent on ARM64
as it for ETMv4x devices.

> +	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.
> +
> +	  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 b6c4a48140ec..e7392a0dddeb 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 cc6b6cabf85f..a7f1a6f09cfb 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -1071,7 +1071,8 @@ 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_SYS) {
>  		dev_err(&csdev->dev, "wrong device subtype in %s\n", function);
>  		return -EINVAL;
>  	}
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
> new file mode 100644
> index 000000000000..f494cef4fb24
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
> @@ -0,0 +1,152 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2021 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#include <linux/amba/bus.h>
> +#include <linux/bitmap.h>
> +#include <linux/coresight.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 <linux/regulator/consumer.h>
> +
> +#include "coresight-priv.h"
> +#include "coresight-tpdm.h"
> +
> +DEFINE_CORESIGHT_DEVLIST(tpdm_devs, "tpdm");
> +
> +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;
> +}
> +
> +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 int tpdm_trace_id(struct coresight_device *csdev)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
> +
> +	return drvdata->traceid;
> +}
> +
> +static const struct coresight_ops_source tpdm_source_ops = {
> +	.trace_id	= tpdm_trace_id,
> +	.enable		= tpdm_enable,
> +	.disable	= tpdm_disable,
> +};
> +
> +static const struct coresight_ops tpdm_cs_ops = {
> +	.source_ops	= &tpdm_source_ops,
> +};
> +
> +static void tpdm_init_default_data(struct tpdm_drvdata *drvdata)
> +{
> +	static int traceid = TPDM_TRACE_ID_START;
> +
> +	drvdata->traceid = traceid++;
> +}

I have been specific on how to properly do this in the last revision.  Given the
above about the MAINTAINERS file, I am not sure that I will continue reviewing this set.

There is also no need to rush another revision as I won't have the bandwidth to
process it before the holidays.

Thanks,
Mathieu

> +
> +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 };
> +
> +	desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
> +	if (!desc.name)
> +		return -ENOMEM;
> +	pdata = coresight_get_platform_data(dev);
> +	if (IS_ERR(pdata))
> +		return PTR_ERR(pdata);
> +	adev->dev.platform_data = pdata;
> +
> +	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);
> +
> +	desc.type = CORESIGHT_DEV_TYPE_SOURCE;
> +	desc.subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_SYS;
> +	desc.ops = &tpdm_cs_ops;
> +	desc.pdata = adev->dev.platform_data;
> +	desc.dev = &adev->dev;
> +	drvdata->csdev = coresight_register(&desc);
> +	if (IS_ERR(drvdata->csdev))
> +		return PTR_ERR(drvdata->csdev);
> +
> +	tpdm_init_default_data(drvdata);
> +	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);
> +}
> +
> +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,
> +};
> +
> +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..980ae90ff1c8
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.h
> @@ -0,0 +1,31 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2021 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +
> +#ifndef _CORESIGHT_CORESIGHT_TPDM_H
> +#define _CORESIGHT_CORESIGHT_TPDM_H
> +
> +/* Default value of the traceid */
> +#define TPDM_TRACE_ID_START 128
> +
> +/**
> + * 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.
> + * @traceid:    value of the current ID for this component.
> + */
> +
> +struct tpdm_drvdata {
> +	void __iomem		*base;
> +	struct device		*dev;
> +	struct coresight_device	*csdev;
> +	struct mutex		lock;
> +	bool			enable;
> +	int			traceid;
> +};
> +
> +#endif  /* _CORESIGHT_CORESIGHT_TPDM_H */
> diff --git a/include/linux/coresight.h b/include/linux/coresight.h
> index 93a2922b7653..e48d463be63b 100644
> --- a/include/linux/coresight.h
> +++ b/include/linux/coresight.h
> @@ -65,6 +65,7 @@ enum coresight_dev_subtype_source {
>  	CORESIGHT_DEV_SUBTYPE_SOURCE_PROC,
>  	CORESIGHT_DEV_SUBTYPE_SOURCE_BUS,
>  	CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE,
> +	CORESIGHT_DEV_SUBTYPE_SOURCE_SYS,
>  };
>  
>  enum coresight_dev_subtype_helper {
> -- 
> 2.17.1
>