Re: [PATCH v9 2/5] soc: qcom: Add SoC sleep stats driver

[Maulik Shah]

Hi,

On 9/25/2021 4:50 AM, Bjorn Andersson wrote:
> On Mon 06 Sep 00:28 CDT 2021, Maulik Shah wrote:
>
> > From: Mahesh Sivasubramanian <msivasub@xxxxxxxxxxxxxx>
> >
> > Let's add a driver to read the stats from remote processor and
> > export to debugfs.
> >
> > The driver creates "qcom_sleep_stats" directory in debugfs and
> > adds files for various low power mode available. Below is sample
> > output with command
> >
> > cat /sys/kernel/debug/qcom_sleep_stats/ddr
> > count = 0
> > Last Entered At = 0
> > Last Exited At = 0
> > Accumulated Duration = 0
> >
> > Signed-off-by: Mahesh Sivasubramanian <msivasub@xxxxxxxxxxxxxx>
> > Signed-off-by: Lina Iyer <ilina@xxxxxxxxxxxxxx>
> > [mkshah: add subsystem sleep stats, create one file for each stat]
> > Signed-off-by: Maulik Shah <mkshah@xxxxxxxxxxxxxx>
> > ---
> >   drivers/soc/qcom/Kconfig           |  10 ++
> >   drivers/soc/qcom/Makefile          |   1 +
> >   drivers/soc/qcom/soc_sleep_stats.c | 241 +++++++++++++++++++++++++++++++++++++
> >   3 files changed, 252 insertions(+)
> >   create mode 100644 drivers/soc/qcom/soc_sleep_stats.c
> >
> > diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> > index 79b568f..e80b63a 100644
> > --- a/drivers/soc/qcom/Kconfig
> > +++ b/drivers/soc/qcom/Kconfig
> > @@ -190,6 +190,16 @@ config QCOM_SOCINFO
> >   	 Say yes here to support the Qualcomm socinfo driver, providing
> >   	 information about the SoC to user space.
> >   
> > +config QCOM_SOC_SLEEP_STATS
> > +	tristate "Qualcomm Technologies, Inc. (QTI) SoC sleep stats driver"
> > +	depends on ARCH_QCOM && DEBUG_FS || COMPILE_TEST
> > +	depends on QCOM_SMEM
> > +	help
> > +	  Qualcomm Technologies, Inc. (QTI) SoC sleep stats driver to read
> > +	  the shared memory exported by the remote processor related to
> > +	  various SoC level low power modes statistics and export to debugfs
> > +	  interface.
> > +
> >   config QCOM_WCNSS_CTRL
> >   	tristate "Qualcomm WCNSS control driver"
> >   	depends on ARCH_QCOM || COMPILE_TEST
> > diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
> > index ad675a6..5f30d74 100644
> > --- a/drivers/soc/qcom/Makefile
> > +++ b/drivers/soc/qcom/Makefile
> > @@ -20,6 +20,7 @@ obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
> >   obj-$(CONFIG_QCOM_SMP2P)	+= smp2p.o
> >   obj-$(CONFIG_QCOM_SMSM)	+= smsm.o
> >   obj-$(CONFIG_QCOM_SOCINFO)	+= socinfo.o
> > +obj-$(CONFIG_QCOM_SOC_SLEEP_STATS)	+= soc_sleep_stats.o
>
> I know that the rest of the modules here does a bad job and have
> completely generic names, but could we rename this "qcom_sleep_stats"
> instead?

Sure renamed in v10.

> >   obj-$(CONFIG_QCOM_WCNSS_CTRL) += wcnss_ctrl.o
> >   obj-$(CONFIG_QCOM_APR) += apr.o
> >   obj-$(CONFIG_QCOM_LLCC) += llcc-qcom.o
> > diff --git a/drivers/soc/qcom/soc_sleep_stats.c b/drivers/soc/qcom/soc_sleep_stats.c
> [..]
> > +static int qcom_soc_sleep_stats_probe(struct platform_device *pdev)
> > +{
> > +	struct resource *res;
> > +	void __iomem *reg;
> > +	struct dentry *root;
> > +	const struct stats_config *config;
> > +	struct stats_data *d;
> > +	int i;
> > +
> > +	config = device_get_match_data(&pdev->dev);
> > +	if (!config)
> > +		return -ENODEV;
> > +
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	if (!res)
> > +		return PTR_ERR(res);
>
> You no longer use this "res".

Thanks for catching this, removed in v10.

> > +
> > +	reg = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
> > +	if (!reg)
>
> IS_ERR()

Updated in v10 to use IS_ERR().

> > +		return -ENOMEM;
> > +
> > +	d = devm_kcalloc(&pdev->dev, config->num_records,
> > +			 sizeof(*d), GFP_KERNEL);
> > +	if (!d)
> > +		return -ENOMEM;
> > +
> > +	for (i = 0; i < config->num_records; i++)
> > +		d[i].appended_stats_avail = config->appended_stats_avail;
> > +
> > +	root = debugfs_create_dir("qcom_sleep_stats", NULL);
> > +
> > +	qcom_create_subsystem_stat_files(root);
> > +	qcom_create_soc_sleep_stat_files(root, reg, d, config->num_records);
> > +
> > +	platform_set_drvdata(pdev, root);
> > +
> > +	return 0;
> > +}
> > +
> > +static int qcom_soc_sleep_stats_remove(struct platform_device *pdev)
> > +{
> > +	struct dentry *root = platform_get_drvdata(pdev);
> > +
> > +	debugfs_remove_recursive(root);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct stats_config rpm_data = {
> > +	.num_records = 2,
> > +	.appended_stats_avail = true,
> > +};
> > +
> > +static const struct stats_config rpmh_data = {
> > +	.num_records = 3,
> > +	.appended_stats_avail = false,
> > +};
> > +
> > +static const struct of_device_id qcom_soc_sleep_stats_table[] = {
> > +	{ .compatible = "qcom,rpm-sleep-stats", .data = &rpm_data },
> > +	{ .compatible = "qcom,rpmh-sleep-stats", .data = &rpmh_data },
> > +	{ }
> > +};
>
> MODULE_DEVICE_TABLE(of, qcom_soc_sleep_stats_table);
>
> Otherwise the module doesn't load automatically.
>
> Regards,
> Bjorn

Added MODULE_DEVICE_TABLE in v10.

Thanks,
Maulik

> > +
> > +static struct platform_driver soc_sleep_stats = {
> > +	.probe = qcom_soc_sleep_stats_probe,
> > +	.remove = qcom_soc_sleep_stats_remove,
> > +	.driver = {
> > +		.name = "soc_sleep_stats",
> > +		.of_match_table = qcom_soc_sleep_stats_table,
> > +	},
> > +};
> > +module_platform_driver(soc_sleep_stats);
> > +
> > +MODULE_DESCRIPTION("Qualcomm Technologies, Inc. (QTI) SoC Sleep Stats driver");
> > +MODULE_LICENSE("GPL v2");
> > --
> > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
> > of Code Aurora Forum, hosted by The Linux Foundation

--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a 
member of Code Aurora Forum, hosted by The Linux Foundation