[PATCH v4 0/2] Introduce RPM Master stats

[PATCH v4 0/2] Introduce RPM Master stats

[Konrad Dybcio]

v3 -> v4:
- Use "data" instead of "d" for naming local struct master_stats_data *
- Add "qcom_" prefix in the debugfs path
- Add "Qualcomm" prefix in MODULE_NAME
- Make the struct __packed__ to avoid padding surprises
  (even though it looks like there shouldn't be any, by eye)
- use IS_ERR for checking debugfs_create_file return value instead of
  nullchecking, that apparently changed..
- Use -ENODEV instead of -EINVAL when a MSG RAM handle is not found
- Add missing of_node_put() after of_parse_phandle()

- Vastly improve the documentation bit

v3: https://lore.kernel.org/r/20230405-topic-master_stats-v3-0-2cb2ba4f2092@linaro.org

v2 -> v3:
- rename rpm-master-stats.yaml to qcom,rpm-master-stats.yaml

v2: https://lore.kernel.org/r/20230405-topic-master_stats-v2-0-51c304ecb610@linaro.org

v1 -> v2:
- Drop the `-` in /properties/compatible to make our entry be of the
  correct type [1/2]
- Change %s to %d for printing out the iterator [2/2]

v1: https://lore.kernel.org/r/20230405-topic-master_stats-v1-0-1b1fa2739953@linaro.org

The RPM MSG ram includes per-subsystem low-power mode entry/exit/
residence/etc. statistics which are very useful for trying to debug
what I'd call "SoC insomnia", or IOW the plaftorm refusing to drop
the voltage rails to a minimum and gate the non-critical clocks.

This series adds a very short and simple driver to query that data
and expose it through debugfs.

The base used for writing this driver is:
https://github.com/sonyxperiadev/kernel/blob/aosp/LA.UM.9.14.r1/drivers/soc/qcom/rpm_master_stat.c

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
---
Konrad Dybcio (2):
      dt-bindings: soc: qcom: Add RPM Master stats
      soc: qcom: Introduce RPM master stats driver

 .../bindings/soc/qcom/qcom,rpm-master-stats.yaml   |  69 +++++++++
 drivers/soc/qcom/Kconfig                           |  11 ++
 drivers/soc/qcom/Makefile                          |   1 +
 drivers/soc/qcom/rpm_master_stats.c                | 162 +++++++++++++++++++++
 4 files changed, 243 insertions(+)
---
base-commit: d3f2cd24819158bb70701c3549e586f9df9cee67
change-id: 20230405-topic-master_stats-ba201a9af93d

Best regards,
-- 
Konrad Dybcio <konrad.dybcio@linaro.org>

[PATCH v4 1/2] dt-bindings: soc: qcom: Add RPM Master stats

[Konrad Dybcio]

The RPM MSG RAM contains per-RPM-master (e.g. APPS, ADSP etc.) sleep
statistics. They let one assess which core is actively preventing the
system from entering a true low-power mode.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
---
 .../bindings/soc/qcom/qcom,rpm-master-stats.yaml   | 69 ++++++++++++++++++++++
 1 file changed, 69 insertions(+)

diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,rpm-master-stats.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,rpm-master-stats.yaml
new file mode 100644
index 000000000000..8a654979ce92
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,rpm-master-stats.yaml
@@ -0,0 +1,69 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/soc/qcom/qcom,rpm-master-stats.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm Technologies, Inc. (QTI) RPM Master Stats
+
+maintainers:
+  - Konrad Dybcio <konrad.dybcio@linaro.org>
+
+description: |
+  The Qualcomm RPM (Resource Power Manager) architecture includes a concept
+  of "RPM Masters". They can be thought of as "the local gang leaders", usually
+  spanning a single subsystem (e.g. APSS, ADSP, CDSP). All of the RPM decisons
+  (particularly around entering hardware-driven low power modes: XO shutdown
+  and total system-wide power collapse) are first made at Master-level, and
+  only then aggregated for the entire system.
+
+  The Master Stats provide a few useful bits that can be used to assess whether
+  our device has entered the desired low-power mode, how long it took to do so,
+  the duration of that residence, how long it took to come back online,
+  how many times a given sleep state was entered and which cores are actively
+  voting for staying awake.
+
+  This scheme has been used on various SoCs in the 2013-2023 era, with some
+  newer or higher-end designs providing this information through an SMEM query.
+
+properties:
+  compatible:
+    const: qcom,rpm-master-stats
+
+  qcom,rpm-msg-ram:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description: Phandle to an RPM MSG RAM slice containing the master stats
+    minItems: 1
+    maxItems: 5
+
+  qcom,master-names:
+    $ref: /schemas/types.yaml#/definitions/string-array
+    description:
+      The name of the RPM Master which owns the MSG RAM slice where this
+      instance of Master Stats resides
+    minItems: 1
+    maxItems: 5
+
+required:
+  - compatible
+  - qcom,rpm-msg-ram
+  - qcom,master-names
+
+additionalProperties: false
+
+examples:
+  - |
+    stats {
+      compatible = "qcom,rpm-master-stats";
+      qcom,rpm-msg-ram = <&apss_master_stats>,
+                         <&mpss_master_stats>,
+                         <&adsp_master_stats>,
+                         <&cdsp_master_stats>,
+                         <&tz_master_stats>;
+      qcom,master-names = "APSS",
+                          "MPSS",
+                          "ADSP",
+                          "CDSP",
+                          "TZ";
+    };
+...

-- 
2.40.0

Re: [PATCH v4 1/2] dt-bindings: soc: qcom: Add RPM Master stats

[Krzysztof Kozlowski]

On 17/04/2023 19:37, Konrad Dybcio wrote:
> The RPM MSG RAM contains per-RPM-master (e.g. APPS, ADSP etc.) sleep
> statistics. They let one assess which core is actively preventing the
> system from entering a true low-power mode.
> 
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> ---

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

[PATCH v4 2/2] soc: qcom: Introduce RPM master stats driver

[Konrad Dybcio]

Introduce a driver to query and expose detailed, per-subsystem (as opposed
to the existing qcom_stats driver which exposes SoC-wide data) about low
power mode states of a given RPM master. That includes the APSS (ARM),
MPSS (modem) and other remote cores, depending on the platform
configuration.

This is a vastly cleaned up and restructured version of a similar
driver found in msm-5.4.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
---
 drivers/soc/qcom/Kconfig            |  11 +++
 drivers/soc/qcom/Makefile           |   1 +
 drivers/soc/qcom/rpm_master_stats.c | 162 ++++++++++++++++++++++++++++++++++++
 3 files changed, 174 insertions(+)

diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index a491718f8064..e597799e8121 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -135,6 +135,17 @@ config QCOM_RMTFS_MEM
 
 	  Say y here if you intend to boot the modem remoteproc.
 
+config QCOM_RPM_MASTER_STATS
+	tristate "Qualcomm RPM Master stats"
+	depends on ARCH_QCOM || COMPILE_TEST
+	help
+	  The RPM Master sleep stats driver provides detailed per-subsystem
+	  sleep/wake data, read from the RPM message RAM. It can be used to
+	  assess whether all the low-power modes available are entered as
+	  expected or to check which part of the SoC prevents it from sleeping.
+
+	  Say y here if you intend to debug or monitor platform sleep.
+
 config QCOM_RPMH
 	tristate "Qualcomm RPM-Hardened (RPMH) Communication"
 	depends on ARCH_QCOM || COMPILE_TEST
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 0f43a88b4894..7349371fdea1 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_QCOM_QMI_HELPERS)	+= qmi_helpers.o
 qmi_helpers-y	+= qmi_encdec.o qmi_interface.o
 obj-$(CONFIG_QCOM_RAMP_CTRL)	+= ramp_controller.o
 obj-$(CONFIG_QCOM_RMTFS_MEM)	+= rmtfs_mem.o
+obj-$(CONFIG_QCOM_RPM_MASTER_STATS)	+= rpm_master_stats.o
 obj-$(CONFIG_QCOM_RPMH)		+= qcom_rpmh.o
 qcom_rpmh-y			+= rpmh-rsc.o
 qcom_rpmh-y			+= rpmh.o
diff --git a/drivers/soc/qcom/rpm_master_stats.c b/drivers/soc/qcom/rpm_master_stats.c
new file mode 100644
index 000000000000..ac87401e2217
--- /dev/null
+++ b/drivers/soc/qcom/rpm_master_stats.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2023, Linaro Limited
+ *
+ * This driver supports what is known as "Master Stats v2" in Qualcomm
+ * downstream kernel terms, which seems to be the only version which has
+ * ever shipped, all the way from 2013 to 2023.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+
+struct master_stats_data {
+	void __iomem *base;
+	const char *label;
+};
+
+struct rpm_master_stats {
+	uint32_t active_cores;
+	uint32_t num_shutdowns;
+	uint64_t shutdown_req;
+	uint64_t wakeup_idx;
+	uint64_t bringup_req;
+	uint64_t bringup_ack;
+	uint32_t wakeup_reason; /* 0 = "rude wakeup", 1 = scheduled wakeup */
+	uint32_t last_sleep_trans_dur;
+	uint32_t last_wake_trans_dur;
+
+	/* Per-subsystem (*not necessarily* SoC-wide) XO shutdown stats */
+	uint32_t xo_count;
+	uint64_t xo_last_enter;
+	uint64_t last_exit;
+	uint64_t xo_total_dur;
+} __packed;
+
+static int master_stats_show(struct seq_file *s, void *unused)
+{
+	struct master_stats_data *data = s->private;
+	struct rpm_master_stats stat;
+
+	memcpy_fromio(&stat, data->base, sizeof(stat));
+
+	seq_printf(s, "%s:\n", data->label);
+
+	seq_printf(s, "\tLast shutdown @ %llu\n", stat.shutdown_req);
+	seq_printf(s, "\tLast bringup req @ %llu\n", stat.bringup_req);
+	seq_printf(s, "\tLast bringup ack @ %llu\n", stat.bringup_ack);
+	seq_printf(s, "\tLast wakeup idx: %llu\n", stat.wakeup_idx);
+	seq_printf(s, "\tLast XO shutdown enter @ %llu\n", stat.xo_last_enter);
+	seq_printf(s, "\tLast XO shutdown exit @ %llu\n", stat.last_exit);
+	seq_printf(s, "\tXO total duration: %llu\n", stat.xo_total_dur);
+	seq_printf(s, "\tLast sleep transition duration: %u\n", stat.last_sleep_trans_dur);
+	seq_printf(s, "\tLast wake transition duration: %u\n", stat.last_wake_trans_dur);
+	seq_printf(s, "\tXO shutdown count: %u\n", stat.xo_count);
+	seq_printf(s, "\tWakeup reason: 0x%x\n", stat.wakeup_reason);
+	seq_printf(s, "\tShutdown count: %u\n", stat.num_shutdowns);
+	seq_printf(s, "\tActive cores bitmask: 0x%x\n", stat.active_cores);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(master_stats);
+
+static int master_stats_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct master_stats_data *data;
+	struct device_node *msgram_np;
+	struct dentry *dent, *root;
+	struct resource res;
+	int count, i, ret;
+
+	count = of_property_count_strings(dev->of_node, "qcom,master-names");
+	if (count < 0)
+		return count;
+
+	data = devm_kzalloc(dev, count * sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	root = debugfs_create_dir("qcom_rpm_master_stats", NULL);
+	platform_set_drvdata(pdev, root);
+
+	for (i = 0; i < count; i++) {
+		msgram_np = of_parse_phandle(dev->of_node, "qcom,rpm-msg-ram", i);
+		if (!msgram_np) {
+			debugfs_remove_recursive(root);
+			return dev_err_probe(dev, -ENODEV,
+					     "Couldn't parse MSG RAM phandle idx %d", i);
+		}
+
+		/*
+		 * Purposefully skip devm_platform helpers as we're using a
+		 * shared resource.
+		 */
+		ret = of_address_to_resource(msgram_np, 0, &res);
+		of_node_put(msgram_np);
+		if (ret < 0) {
+			debugfs_remove_recursive(root);
+			return ret;
+		}
+
+		data[i].base = devm_ioremap(dev, res.start, resource_size(&res));
+		if (IS_ERR(data[i].base)) {
+			debugfs_remove_recursive(root);
+			return dev_err_probe(dev, -EINVAL,
+					     "Could not map the MSG RAM slice idx %d!\n", i);
+		}
+
+		ret = of_property_read_string_index(dev->of_node, "qcom,master-names", i,
+						    &data[i].label);
+		if (ret < 0) {
+			debugfs_remove_recursive(root);
+			return dev_err_probe(dev, ret,
+					     "Could not read name idx %d!\n", i);
+		}
+
+		/*
+		 * Generally it's not advised to fail on debugfs errors, but this
+		 * driver's only job is exposing data therein.
+		 */
+		dent = debugfs_create_file(data[i].label, 0444, root,
+					   &data[i], &master_stats_fops);
+		if (IS_ERR(dent)) {
+			debugfs_remove_recursive(root);
+			return -EINVAL;
+		}
+	}
+
+	device_set_pm_not_required(dev);
+
+	return 0;
+}
+
+static void master_stats_remove(struct platform_device *pdev)
+{
+	struct dentry *root = platform_get_drvdata(pdev);
+
+	debugfs_remove_recursive(root);
+}
+
+static const struct of_device_id rpm_master_table[] = {
+	{ .compatible = "qcom,rpm-master-stats" },
+	{ },
+};
+
+static struct platform_driver master_stats_driver = {
+	.probe = master_stats_probe,
+	.remove_new = master_stats_remove,
+	.driver = {
+		.name = "rpm_master_stats",
+		.of_match_table = rpm_master_table,
+	},
+};
+module_platform_driver(master_stats_driver);
+
+MODULE_DESCRIPTION("Qualcomm RPM Master Statistics driver");
+MODULE_LICENSE("GPL");

-- 
2.40.0

Re: [PATCH v4 2/2] soc: qcom: Introduce RPM master stats driver

[Manivannan Sadhasivam]

On Mon, Apr 17, 2023 at 07:37:53PM +0200, Konrad Dybcio wrote:
> Introduce a driver to query and expose detailed, per-subsystem (as opposed
> to the existing qcom_stats driver which exposes SoC-wide data) about low
> power mode states of a given RPM master. That includes the APSS (ARM),
> MPSS (modem) and other remote cores, depending on the platform
> configuration.
> 
> This is a vastly cleaned up and restructured version of a similar
> driver found in msm-5.4.
> 
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> ---
>  drivers/soc/qcom/Kconfig            |  11 +++
>  drivers/soc/qcom/Makefile           |   1 +
>  drivers/soc/qcom/rpm_master_stats.c | 162 ++++++++++++++++++++++++++++++++++++
>  3 files changed, 174 insertions(+)
> 
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index a491718f8064..e597799e8121 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -135,6 +135,17 @@ config QCOM_RMTFS_MEM
>  
>  	  Say y here if you intend to boot the modem remoteproc.
>  
> +config QCOM_RPM_MASTER_STATS
> +	tristate "Qualcomm RPM Master stats"
> +	depends on ARCH_QCOM || COMPILE_TEST
> +	help
> +	  The RPM Master sleep stats driver provides detailed per-subsystem
> +	  sleep/wake data, read from the RPM message RAM. It can be used to
> +	  assess whether all the low-power modes available are entered as
> +	  expected or to check which part of the SoC prevents it from sleeping.
> +
> +	  Say y here if you intend to debug or monitor platform sleep.
> +
>  config QCOM_RPMH
>  	tristate "Qualcomm RPM-Hardened (RPMH) Communication"
>  	depends on ARCH_QCOM || COMPILE_TEST
> diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
> index 0f43a88b4894..7349371fdea1 100644
> --- a/drivers/soc/qcom/Makefile
> +++ b/drivers/soc/qcom/Makefile
> @@ -14,6 +14,7 @@ obj-$(CONFIG_QCOM_QMI_HELPERS)	+= qmi_helpers.o
>  qmi_helpers-y	+= qmi_encdec.o qmi_interface.o
>  obj-$(CONFIG_QCOM_RAMP_CTRL)	+= ramp_controller.o
>  obj-$(CONFIG_QCOM_RMTFS_MEM)	+= rmtfs_mem.o
> +obj-$(CONFIG_QCOM_RPM_MASTER_STATS)	+= rpm_master_stats.o
>  obj-$(CONFIG_QCOM_RPMH)		+= qcom_rpmh.o
>  qcom_rpmh-y			+= rpmh-rsc.o
>  qcom_rpmh-y			+= rpmh.o
> diff --git a/drivers/soc/qcom/rpm_master_stats.c b/drivers/soc/qcom/rpm_master_stats.c
> new file mode 100644
> index 000000000000..ac87401e2217
> --- /dev/null
> +++ b/drivers/soc/qcom/rpm_master_stats.c
> @@ -0,0 +1,162 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
> + * Copyright (c) 2023, Linaro Limited
> + *
> + * This driver supports what is known as "Master Stats v2" in Qualcomm
> + * downstream kernel terms, which seems to be the only version which has
> + * ever shipped, all the way from 2013 to 2023.
> + */
> +
> +#include <linux/debugfs.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +
> +struct master_stats_data {
> +	void __iomem *base;
> +	const char *label;
> +};
> +
> +struct rpm_master_stats {
> +	uint32_t active_cores;
> +	uint32_t num_shutdowns;
> +	uint64_t shutdown_req;
> +	uint64_t wakeup_idx;
> +	uint64_t bringup_req;
> +	uint64_t bringup_ack;
> +	uint32_t wakeup_reason; /* 0 = "rude wakeup", 1 = scheduled wakeup */
> +	uint32_t last_sleep_trans_dur;
> +	uint32_t last_wake_trans_dur;
> +
> +	/* Per-subsystem (*not necessarily* SoC-wide) XO shutdown stats */
> +	uint32_t xo_count;
> +	uint64_t xo_last_enter;
> +	uint64_t last_exit;
> +	uint64_t xo_total_dur;

Still no u64, u32.

> +} __packed;
> +

[...]

> +		/*
> +		 * Generally it's not advised to fail on debugfs errors, but this
> +		 * driver's only job is exposing data therein.
> +		 */
> +		dent = debugfs_create_file(data[i].label, 0444, root,
> +					   &data[i], &master_stats_fops);
> +		if (IS_ERR(dent)) {
> +			debugfs_remove_recursive(root);
> +			return -EINVAL;

PTR_ERR(dent). Also it doesn't hurt to use dev_err_probe() here.

> +		}
> +	}
> +
> +	device_set_pm_not_required(dev);
> +
> +	return 0;
> +}
> +
> +static void master_stats_remove(struct platform_device *pdev)
> +{
> +	struct dentry *root = platform_get_drvdata(pdev);
> +
> +	debugfs_remove_recursive(root);
> +}
> +
> +static const struct of_device_id rpm_master_table[] = {
> +	{ .compatible = "qcom,rpm-master-stats" },
> +	{ },
> +};
> +
> +static struct platform_driver master_stats_driver = {
> +	.probe = master_stats_probe,
> +	.remove_new = master_stats_remove,
> +	.driver = {
> +		.name = "rpm_master_stats",

qcom_rpm_master_stats

- Mani

> +		.of_match_table = rpm_master_table,
> +	},
> +};
> +module_platform_driver(master_stats_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm RPM Master Statistics driver");
> +MODULE_LICENSE("GPL");
> 
> -- 
> 2.40.0
> 

-- 
மணிவண்ணன் சதாசிவம்

Re: [PATCH v4 2/2] soc: qcom: Introduce RPM master stats driver

[Konrad Dybcio]

On 18.04.2023 14:50, Manivannan Sadhasivam wrote:
> On Mon, Apr 17, 2023 at 07:37:53PM +0200, Konrad Dybcio wrote:
>> Introduce a driver to query and expose detailed, per-subsystem (as opposed
>> to the existing qcom_stats driver which exposes SoC-wide data) about low
>> power mode states of a given RPM master. That includes the APSS (ARM),
>> MPSS (modem) and other remote cores, depending on the platform
>> configuration.
>>
>> This is a vastly cleaned up and restructured version of a similar
>> driver found in msm-5.4.
>>
>> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
>> ---
>>  drivers/soc/qcom/Kconfig            |  11 +++
>>  drivers/soc/qcom/Makefile           |   1 +
>>  drivers/soc/qcom/rpm_master_stats.c | 162 ++++++++++++++++++++++++++++++++++++
>>  3 files changed, 174 insertions(+)
>>
>> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
>> index a491718f8064..e597799e8121 100644
>> --- a/drivers/soc/qcom/Kconfig
>> +++ b/drivers/soc/qcom/Kconfig
>> @@ -135,6 +135,17 @@ config QCOM_RMTFS_MEM
>>  
>>  	  Say y here if you intend to boot the modem remoteproc.
>>  
>> +config QCOM_RPM_MASTER_STATS
>> +	tristate "Qualcomm RPM Master stats"
>> +	depends on ARCH_QCOM || COMPILE_TEST
>> +	help
>> +	  The RPM Master sleep stats driver provides detailed per-subsystem
>> +	  sleep/wake data, read from the RPM message RAM. It can be used to
>> +	  assess whether all the low-power modes available are entered as
>> +	  expected or to check which part of the SoC prevents it from sleeping.
>> +
>> +	  Say y here if you intend to debug or monitor platform sleep.
>> +
>>  config QCOM_RPMH
>>  	tristate "Qualcomm RPM-Hardened (RPMH) Communication"
>>  	depends on ARCH_QCOM || COMPILE_TEST
>> diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
>> index 0f43a88b4894..7349371fdea1 100644
>> --- a/drivers/soc/qcom/Makefile
>> +++ b/drivers/soc/qcom/Makefile
>> @@ -14,6 +14,7 @@ obj-$(CONFIG_QCOM_QMI_HELPERS)	+= qmi_helpers.o
>>  qmi_helpers-y	+= qmi_encdec.o qmi_interface.o
>>  obj-$(CONFIG_QCOM_RAMP_CTRL)	+= ramp_controller.o
>>  obj-$(CONFIG_QCOM_RMTFS_MEM)	+= rmtfs_mem.o
>> +obj-$(CONFIG_QCOM_RPM_MASTER_STATS)	+= rpm_master_stats.o
>>  obj-$(CONFIG_QCOM_RPMH)		+= qcom_rpmh.o
>>  qcom_rpmh-y			+= rpmh-rsc.o
>>  qcom_rpmh-y			+= rpmh.o
>> diff --git a/drivers/soc/qcom/rpm_master_stats.c b/drivers/soc/qcom/rpm_master_stats.c
>> new file mode 100644
>> index 000000000000..ac87401e2217
>> --- /dev/null
>> +++ b/drivers/soc/qcom/rpm_master_stats.c
>> @@ -0,0 +1,162 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
>> + * Copyright (c) 2023, Linaro Limited
>> + *
>> + * This driver supports what is known as "Master Stats v2" in Qualcomm
>> + * downstream kernel terms, which seems to be the only version which has
>> + * ever shipped, all the way from 2013 to 2023.
>> + */
>> +
>> +#include <linux/debugfs.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/platform_device.h>
>> +
>> +struct master_stats_data {
>> +	void __iomem *base;
>> +	const char *label;
>> +};
>> +
>> +struct rpm_master_stats {
>> +	uint32_t active_cores;
>> +	uint32_t num_shutdowns;
>> +	uint64_t shutdown_req;
>> +	uint64_t wakeup_idx;
>> +	uint64_t bringup_req;
>> +	uint64_t bringup_ack;
>> +	uint32_t wakeup_reason; /* 0 = "rude wakeup", 1 = scheduled wakeup */
>> +	uint32_t last_sleep_trans_dur;
>> +	uint32_t last_wake_trans_dur;
>> +
>> +	/* Per-subsystem (*not necessarily* SoC-wide) XO shutdown stats */
>> +	uint32_t xo_count;
>> +	uint64_t xo_last_enter;
>> +	uint64_t last_exit;
>> +	uint64_t xo_total_dur;
> 
> Still no u64, u32.
Right, missed that part..

> 
>> +} __packed;
>> +
> 
> [...]
> 
>> +		/*
>> +		 * Generally it's not advised to fail on debugfs errors, but this
>> +		 * driver's only job is exposing data therein.
>> +		 */
>> +		dent = debugfs_create_file(data[i].label, 0444, root,
>> +					   &data[i], &master_stats_fops);
>> +		if (IS_ERR(dent)) {
>> +			debugfs_remove_recursive(root);
>> +			return -EINVAL;
> 
> PTR_ERR(dent). Also it doesn't hurt to use dev_err_probe() here.
Totally makes sense.

> 
>> +		}
>> +	}
>> +
>> +	device_set_pm_not_required(dev);
>> +
>> +	return 0;
>> +}
>> +
>> +static void master_stats_remove(struct platform_device *pdev)
>> +{
>> +	struct dentry *root = platform_get_drvdata(pdev);
>> +
>> +	debugfs_remove_recursive(root);
>> +}
>> +
>> +static const struct of_device_id rpm_master_table[] = {
>> +	{ .compatible = "qcom,rpm-master-stats" },
>> +	{ },
>> +};
>> +
>> +static struct platform_driver master_stats_driver = {
>> +	.probe = master_stats_probe,
>> +	.remove_new = master_stats_remove,
>> +	.driver = {
>> +		.name = "rpm_master_stats",
> 
> qcom_rpm_master_stats
> 
Fixed it everywhere else except here, will do!

Konrad
> - Mani
> 
>> +		.of_match_table = rpm_master_table,
>> +	},
>> +};
>> +module_platform_driver(master_stats_driver);
>> +
>> +MODULE_DESCRIPTION("Qualcomm RPM Master Statistics driver");
>> +MODULE_LICENSE("GPL");
>>
>> -- 
>> 2.40.0
>>
>