[PATCH v7 0/2] Add temperature notification support

[PATCH v7 0/2] Add temperature notification support

[Avri Altman]

v6 -> v7:
 - some more useless initializations
 
v5 -> v6:
 - remove useless initializations
 
v4 - > v5:
 - Fix improper return error values
 
v3 -> v4:
 - Attend Guenter's comments

v2 -> v3:
 - Attend Bart's & Guenter's comments

v1 -> v2:
 - Add a hw monitor device if both the platform & the device support it
 - Remove the sysfs patch: no need to duplicate /sys/class/hwmon

UFS3.0 allows using the ufs device as a temperature sensor. The purpose
of this optional feature is to provide notification to the host of the
UFS device case temperature. It allows reading of a rough estimate
(+-10 degrees centigrade) of the current case temperature, and setting a
lower and upper temperature bounds, in which the device will trigger an
applicable exception event.

A previous attempt [1] tried a comprehensive approach.  Still, it was
unsuccessful. Here is a more modest approach that introduces just the
bare minimum to support temperature notification.

Thanks,
Avri

[1] https://lore.kernel.org/lkml/1582450522-13256-1-git-send-email-avi.shchislowski@wdc.com/


Avri Altman (2):
  scsi: ufs: Probe for temperature notification support
  scsi: ufs: Add temperature notification exception handling

 drivers/scsi/ufs/Kconfig     |   9 ++
 drivers/scsi/ufs/Makefile    |   1 +
 drivers/scsi/ufs/ufs-hwmon.c | 210 +++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufs.h       |   7 ++
 drivers/scsi/ufs/ufshcd.c    |  47 ++++++++
 drivers/scsi/ufs/ufshcd.h    |  20 ++++
 6 files changed, 294 insertions(+)
 create mode 100644 drivers/scsi/ufs/ufs-hwmon.c

-- 
2.17.1

[PATCH v7 1/2] scsi: ufs: Probe for temperature notification support

[Avri Altman]

Probe the dExtendedUFSFeaturesSupport register for the device's
temperature notification support, and if supported, add a hw monitor
device.

Signed-off-by: Avri Altman <avri.altman@wdc.com>
---
 drivers/scsi/ufs/Kconfig     |   9 ++
 drivers/scsi/ufs/Makefile    |   1 +
 drivers/scsi/ufs/ufs-hwmon.c | 198 +++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufs.h       |   7 ++
 drivers/scsi/ufs/ufshcd.c    |  26 +++++
 drivers/scsi/ufs/ufshcd.h    |  18 ++++
 6 files changed, 259 insertions(+)
 create mode 100644 drivers/scsi/ufs/ufs-hwmon.c

diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
index 432df76e6318..565e8aa6319d 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -199,3 +199,12 @@ config SCSI_UFS_FAULT_INJECTION
 	help
 	  Enable fault injection support in the UFS driver. This makes it easier
 	  to test the UFS error handler and abort handler.
+
+config SCSI_UFS_HWMON
+	bool "UFS  Temperature Notification"
+	depends on SCSI_UFSHCD && HWMON
+	help
+	  This provides support for UFS hardware monitoring. If enabled,
+	  a hardware monitoring device will be created for the UFS device.
+
+	  If unsure, say N.
diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
index c407da9b5171..966048875b50 100644
--- a/drivers/scsi/ufs/Makefile
+++ b/drivers/scsi/ufs/Makefile
@@ -10,6 +10,7 @@ ufshcd-core-$(CONFIG_SCSI_UFS_BSG)	+= ufs_bsg.o
 ufshcd-core-$(CONFIG_SCSI_UFS_CRYPTO)	+= ufshcd-crypto.o
 ufshcd-core-$(CONFIG_SCSI_UFS_HPB)	+= ufshpb.o
 ufshcd-core-$(CONFIG_SCSI_UFS_FAULT_INJECTION) += ufs-fault-injection.o
+ufshcd-core-$(CONFIG_SCSI_UFS_HWMON) += ufs-hwmon.o
 
 obj-$(CONFIG_SCSI_UFS_DWC_TC_PCI) += tc-dwc-g210-pci.o ufshcd-dwc.o tc-dwc-g210.o
 obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) += tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-dwc-g210.o
diff --git a/drivers/scsi/ufs/ufs-hwmon.c b/drivers/scsi/ufs/ufs-hwmon.c
new file mode 100644
index 000000000000..33b66736aaa4
--- /dev/null
+++ b/drivers/scsi/ufs/ufs-hwmon.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * UFS hardware monitoring support
+ * Copyright (c) 2021, Western Digital Corporation
+ */
+
+#include <linux/hwmon.h>
+#include <linux/units.h>
+
+#include "ufshcd.h"
+
+struct ufs_hwmon_data {
+	struct ufs_hba *hba;
+	u8 mask;
+};
+
+static int ufs_read_temp_enable(struct ufs_hba *hba, u8 mask, long *val)
+{
+	u32 ee_mask;
+	int err;
+
+	err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, QUERY_ATTR_IDN_EE_CONTROL, 0, 0,
+				&ee_mask);
+	if (err)
+		return err;
+
+	*val = (mask & ee_mask & MASK_EE_TOO_HIGH_TEMP) || (mask & ee_mask & MASK_EE_TOO_LOW_TEMP);
+
+	return 0;
+}
+
+static int ufs_get_temp(struct ufs_hba *hba, enum attr_idn idn, long *val)
+{
+	u32 value;
+	int err;
+
+	err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, idn, 0, 0, &value);
+	if (err)
+		return err;
+
+	if (value == 0)
+		return -ENODATA;
+
+	*val = ((long)value - 80) * MILLIDEGREE_PER_DEGREE;
+
+	return 0;
+}
+
+static int ufs_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+			  long *val)
+{
+	struct ufs_hwmon_data *data = dev_get_drvdata(dev);
+	struct ufs_hba *hba = data->hba;
+	int err;
+
+	down(&hba->host_sem);
+
+	if (!ufshcd_is_user_access_allowed(hba)) {
+		up(&hba->host_sem);
+		return -EBUSY;
+	}
+
+	ufshcd_rpm_get_sync(hba);
+
+	switch (attr) {
+	case hwmon_temp_enable:
+		err = ufs_read_temp_enable(hba, data->mask, val);
+
+		break;
+	case hwmon_temp_crit:
+		err = ufs_get_temp(hba, QUERY_ATTR_IDN_HIGH_TEMP_BOUND, val);
+
+		break;
+	case hwmon_temp_lcrit:
+		err = ufs_get_temp(hba, QUERY_ATTR_IDN_LOW_TEMP_BOUND, val);
+
+		break;
+	case hwmon_temp_input:
+		err = ufs_get_temp(hba, QUERY_ATTR_IDN_CASE_ROUGH_TEMP, val);
+
+		break;
+	default:
+		err = -EOPNOTSUPP;
+
+		break;
+	}
+
+	ufshcd_rpm_put_sync(hba);
+
+	up(&hba->host_sem);
+
+	return err;
+}
+
+static int ufs_hwmon_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+			   long val)
+{
+	struct ufs_hwmon_data *data = dev_get_drvdata(dev);
+	struct ufs_hba *hba = data->hba;
+	int err;
+
+	if (attr != hwmon_temp_enable)
+		return -EINVAL;
+
+	if (val != 0 && val != 1)
+		return -EINVAL;
+
+	down(&hba->host_sem);
+
+	if (!ufshcd_is_user_access_allowed(hba)) {
+		up(&hba->host_sem);
+		return -EBUSY;
+	}
+
+	ufshcd_rpm_get_sync(hba);
+
+	if (val == 1)
+		err = ufshcd_update_ee_usr_mask(hba, MASK_EE_URGENT_TEMP, 0);
+	else
+		err = ufshcd_update_ee_usr_mask(hba, 0, MASK_EE_URGENT_TEMP);
+
+	ufshcd_rpm_put_sync(hba);
+
+	up(&hba->host_sem);
+
+	return err;
+}
+
+static umode_t ufs_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr,
+				    int channel)
+{
+	if (type != hwmon_temp)
+		return 0;
+
+	switch (attr) {
+	case hwmon_temp_enable:
+		return 0644;
+	case hwmon_temp_crit:
+	case hwmon_temp_lcrit:
+	case hwmon_temp_input:
+		return 0444;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static const struct hwmon_channel_info *ufs_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(temp, HWMON_T_ENABLE | HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_LCRIT),
+	NULL
+};
+
+static const struct hwmon_ops ufs_hwmon_ops = {
+	.is_visible	= ufs_hwmon_is_visible,
+	.read		= ufs_hwmon_read,
+	.write		= ufs_hwmon_write,
+};
+
+static const struct hwmon_chip_info ufs_hwmon_hba_info = {
+	.ops	= &ufs_hwmon_ops,
+	.info	= ufs_hwmon_info,
+};
+
+void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask)
+{
+	struct device *dev = hba->dev;
+	struct ufs_hwmon_data *data;
+	struct device *hwmon;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return;
+
+	data->hba = hba;
+	data->mask = mask;
+
+	hwmon = hwmon_device_register_with_info(dev, "ufs", data, &ufs_hwmon_hba_info, NULL);
+	if (IS_ERR(hwmon)) {
+		dev_warn(dev, "Failed to instantiate hwmon device\n");
+		kfree(data);
+		return;
+	}
+
+	hba->hwmon_device = hwmon;
+}
+
+void ufs_hwmon_remove(struct ufs_hba *hba)
+{
+	struct ufs_hwmon_data *data;
+
+	if (!hba->hwmon_device)
+		return;
+
+	data = dev_get_drvdata(hba->hwmon_device);
+	hwmon_device_unregister(hba->hwmon_device);
+	hba->hwmon_device = NULL;
+	kfree(data);
+}
diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index 8c6b38b1b142..0bfdca3e648e 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -152,6 +152,9 @@ enum attr_idn {
 	QUERY_ATTR_IDN_PSA_STATE		= 0x15,
 	QUERY_ATTR_IDN_PSA_DATA_SIZE		= 0x16,
 	QUERY_ATTR_IDN_REF_CLK_GATING_WAIT_TIME	= 0x17,
+	QUERY_ATTR_IDN_CASE_ROUGH_TEMP          = 0x18,
+	QUERY_ATTR_IDN_HIGH_TEMP_BOUND          = 0x19,
+	QUERY_ATTR_IDN_LOW_TEMP_BOUND           = 0x1A,
 	QUERY_ATTR_IDN_WB_FLUSH_STATUS	        = 0x1C,
 	QUERY_ATTR_IDN_AVAIL_WB_BUFF_SIZE       = 0x1D,
 	QUERY_ATTR_IDN_WB_BUFF_LIFE_TIME_EST    = 0x1E,
@@ -338,6 +341,9 @@ enum {
 
 /* Possible values for dExtendedUFSFeaturesSupport */
 enum {
+	UFS_DEV_LOW_TEMP_NOTIF		= BIT(4),
+	UFS_DEV_HIGH_TEMP_NOTIF		= BIT(5),
+	UFS_DEV_EXT_TEMP_NOTIF		= BIT(6),
 	UFS_DEV_HPB_SUPPORT		= BIT(7),
 	UFS_DEV_WRITE_BOOSTER_SUP	= BIT(8),
 };
@@ -370,6 +376,7 @@ enum {
 	MASK_EE_WRITEBOOSTER_EVENT	= BIT(5),
 	MASK_EE_PERFORMANCE_THROTTLING	= BIT(6),
 };
+#define MASK_EE_URGENT_TEMP (MASK_EE_TOO_HIGH_TEMP | MASK_EE_TOO_LOW_TEMP)
 
 /* Background operation status */
 enum bkops_status {
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 3841ab49f556..ce22340024ce 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7469,6 +7469,29 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
 	hba->caps &= ~UFSHCD_CAP_WB_EN;
 }
 
+static void ufshcd_temp_notif_probe(struct ufs_hba *hba, u8 *desc_buf)
+{
+	struct ufs_dev_info *dev_info = &hba->dev_info;
+	u32 ext_ufs_feature;
+	u8 mask = 0;
+
+	if (!(hba->caps & UFSHCD_CAP_TEMP_NOTIF) || dev_info->wspecversion < 0x300)
+		return;
+
+	ext_ufs_feature = get_unaligned_be32(desc_buf + DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
+
+	if (ext_ufs_feature & UFS_DEV_LOW_TEMP_NOTIF)
+		mask |= MASK_EE_TOO_LOW_TEMP;
+
+	if (ext_ufs_feature & UFS_DEV_HIGH_TEMP_NOTIF)
+		mask |= MASK_EE_TOO_HIGH_TEMP;
+
+	if (mask) {
+		ufshcd_enable_ee(hba, mask);
+		ufs_hwmon_probe(hba, mask);
+	}
+}
+
 void ufshcd_fixup_dev_quirks(struct ufs_hba *hba, struct ufs_dev_fix *fixups)
 {
 	struct ufs_dev_fix *f;
@@ -7564,6 +7587,8 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
 
 	ufshcd_wb_probe(hba, desc_buf);
 
+	ufshcd_temp_notif_probe(hba, desc_buf);
+
 	/*
 	 * ufshcd_read_string_desc returns size of the string
 	 * reset the error value
@@ -9408,6 +9433,7 @@ void ufshcd_remove(struct ufs_hba *hba)
 {
 	if (hba->sdev_ufs_device)
 		ufshcd_rpm_get_sync(hba);
+	ufs_hwmon_remove(hba);
 	ufs_bsg_remove(hba);
 	ufshpb_remove(hba);
 	ufs_sysfs_remove_nodes(hba->dev);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 52ea6f350b18..021c858955af 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -653,6 +653,12 @@ enum ufshcd_caps {
 	 * in order to exit DeepSleep state.
 	 */
 	UFSHCD_CAP_DEEPSLEEP				= 1 << 10,
+
+	/*
+	 * This capability allows the host controller driver to use temperature
+	 * notification if it is supported by the UFS device.
+	 */
+	UFSHCD_CAP_TEMP_NOTIF				= 1 << 11,
 };
 
 struct ufs_hba_variant_params {
@@ -789,6 +795,10 @@ struct ufs_hba {
 	struct scsi_device *sdev_ufs_device;
 	struct scsi_device *sdev_rpmb;
 
+#ifdef CONFIG_SCSI_UFS_HWMON
+	struct device *hwmon_device;
+#endif
+
 	enum ufs_dev_pwr_mode curr_dev_pwr_mode;
 	enum uic_link_state uic_link_state;
 	/* Desired UFS power management level during runtime PM */
@@ -1049,6 +1059,14 @@ static inline u8 ufshcd_wb_get_query_index(struct ufs_hba *hba)
 	return 0;
 }
 
+#ifdef CONFIG_SCSI_UFS_HWMON
+void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask);
+void ufs_hwmon_remove(struct ufs_hba *hba);
+#else
+static inline void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask) {}
+static inline void ufs_hwmon_remove(struct ufs_hba *hba) {}
+#endif
+
 #ifdef CONFIG_PM
 extern int ufshcd_runtime_suspend(struct device *dev);
 extern int ufshcd_runtime_resume(struct device *dev);
-- 
2.17.1

[PATCH v7 2/2] scsi: ufs: Add temperature notification exception handling

[Avri Altman]

The device may notify the host of an extreme temperature by using the
exception event mechanism. The exception can be raised when the device’s
Tcase temperature is either too high or too low.

It is essentially up to the platform to decide what further actions need
to be taken. leave a placeholder for a designated vop for that.

Signed-off-by: Avri Altman <avri.altman@wdc.com>
---
 drivers/scsi/ufs/ufs-hwmon.c | 12 ++++++++++++
 drivers/scsi/ufs/ufshcd.c    | 21 +++++++++++++++++++++
 drivers/scsi/ufs/ufshcd.h    |  2 ++
 3 files changed, 35 insertions(+)

diff --git a/drivers/scsi/ufs/ufs-hwmon.c b/drivers/scsi/ufs/ufs-hwmon.c
index 33b66736aaa4..74855491dc8f 100644
--- a/drivers/scsi/ufs/ufs-hwmon.c
+++ b/drivers/scsi/ufs/ufs-hwmon.c
@@ -196,3 +196,15 @@ void ufs_hwmon_remove(struct ufs_hba *hba)
 	hba->hwmon_device = NULL;
 	kfree(data);
 }
+
+void ufs_hwmon_notify_event(struct ufs_hba *hba, u8 ee_mask)
+{
+	if (!hba->hwmon_device)
+		return;
+
+	if (ee_mask & MASK_EE_TOO_HIGH_TEMP)
+		hwmon_notify_event(hba->hwmon_device, hwmon_temp, hwmon_temp_max_alarm, 0);
+
+	if (ee_mask & MASK_EE_TOO_LOW_TEMP)
+		hwmon_notify_event(hba->hwmon_device, hwmon_temp, hwmon_temp_min_alarm, 0);
+}
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index ce22340024ce..debef631c89a 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5642,6 +5642,24 @@ static void ufshcd_bkops_exception_event_handler(struct ufs_hba *hba)
 				__func__, err);
 }
 
+static void ufshcd_temp_exception_event_handler(struct ufs_hba *hba, u16 status)
+{
+	u32 value;
+
+	if (ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+				QUERY_ATTR_IDN_CASE_ROUGH_TEMP, 0, 0, &value))
+		return;
+
+	dev_info(hba->dev, "exception Tcase %d\n", value - 80);
+
+	ufs_hwmon_notify_event(hba, status & MASK_EE_URGENT_TEMP);
+
+	/*
+	 * A placeholder for the platform vendors to add whatever additional
+	 * steps required
+	 */
+}
+
 static int __ufshcd_wb_toggle(struct ufs_hba *hba, bool set, enum flag_idn idn)
 {
 	u8 index;
@@ -5821,6 +5839,9 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
 	if (status & hba->ee_drv_mask & MASK_EE_URGENT_BKOPS)
 		ufshcd_bkops_exception_event_handler(hba);
 
+	if (status & hba->ee_drv_mask & MASK_EE_URGENT_TEMP)
+		ufshcd_temp_exception_event_handler(hba, status);
+
 	ufs_debugfs_exception_event(hba, status);
 out:
 	ufshcd_scsi_unblock_requests(hba);
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 021c858955af..92d05329de68 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -1062,9 +1062,11 @@ static inline u8 ufshcd_wb_get_query_index(struct ufs_hba *hba)
 #ifdef CONFIG_SCSI_UFS_HWMON
 void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask);
 void ufs_hwmon_remove(struct ufs_hba *hba);
+void ufs_hwmon_notify_event(struct ufs_hba *hba, u8 ee_mask);
 #else
 static inline void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask) {}
 static inline void ufs_hwmon_remove(struct ufs_hba *hba) {}
+static inline void ufs_hwmon_notify_event(struct ufs_hba *hba, u8 ee_mask) {}
 #endif
 
 #ifdef CONFIG_PM
-- 
2.17.1

Re: [PATCH v7 1/2] scsi: ufs: Probe for temperature notification support

[Guenter Roeck]

On Wed, Sep 15, 2021 at 09:04:06AM +0300, Avri Altman wrote:
> Probe the dExtendedUFSFeaturesSupport register for the device's
> temperature notification support, and if supported, add a hw monitor
> device.
> 
> Signed-off-by: Avri Altman <avri.altman@wdc.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  drivers/scsi/ufs/Kconfig     |   9 ++
>  drivers/scsi/ufs/Makefile    |   1 +
>  drivers/scsi/ufs/ufs-hwmon.c | 198 +++++++++++++++++++++++++++++++++++
>  drivers/scsi/ufs/ufs.h       |   7 ++
>  drivers/scsi/ufs/ufshcd.c    |  26 +++++
>  drivers/scsi/ufs/ufshcd.h    |  18 ++++
>  6 files changed, 259 insertions(+)
>  create mode 100644 drivers/scsi/ufs/ufs-hwmon.c
> 
> diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
> index 432df76e6318..565e8aa6319d 100644
> --- a/drivers/scsi/ufs/Kconfig
> +++ b/drivers/scsi/ufs/Kconfig
> @@ -199,3 +199,12 @@ config SCSI_UFS_FAULT_INJECTION
>  	help
>  	  Enable fault injection support in the UFS driver. This makes it easier
>  	  to test the UFS error handler and abort handler.
> +
> +config SCSI_UFS_HWMON
> +	bool "UFS  Temperature Notification"
> +	depends on SCSI_UFSHCD && HWMON
> +	help
> +	  This provides support for UFS hardware monitoring. If enabled,
> +	  a hardware monitoring device will be created for the UFS device.
> +
> +	  If unsure, say N.
> diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
> index c407da9b5171..966048875b50 100644
> --- a/drivers/scsi/ufs/Makefile
> +++ b/drivers/scsi/ufs/Makefile
> @@ -10,6 +10,7 @@ ufshcd-core-$(CONFIG_SCSI_UFS_BSG)	+= ufs_bsg.o
>  ufshcd-core-$(CONFIG_SCSI_UFS_CRYPTO)	+= ufshcd-crypto.o
>  ufshcd-core-$(CONFIG_SCSI_UFS_HPB)	+= ufshpb.o
>  ufshcd-core-$(CONFIG_SCSI_UFS_FAULT_INJECTION) += ufs-fault-injection.o
> +ufshcd-core-$(CONFIG_SCSI_UFS_HWMON) += ufs-hwmon.o
>  
>  obj-$(CONFIG_SCSI_UFS_DWC_TC_PCI) += tc-dwc-g210-pci.o ufshcd-dwc.o tc-dwc-g210.o
>  obj-$(CONFIG_SCSI_UFS_DWC_TC_PLATFORM) += tc-dwc-g210-pltfrm.o ufshcd-dwc.o tc-dwc-g210.o
> diff --git a/drivers/scsi/ufs/ufs-hwmon.c b/drivers/scsi/ufs/ufs-hwmon.c
> new file mode 100644
> index 000000000000..33b66736aaa4
> --- /dev/null
> +++ b/drivers/scsi/ufs/ufs-hwmon.c
> @@ -0,0 +1,198 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * UFS hardware monitoring support
> + * Copyright (c) 2021, Western Digital Corporation
> + */
> +
> +#include <linux/hwmon.h>
> +#include <linux/units.h>
> +
> +#include "ufshcd.h"
> +
> +struct ufs_hwmon_data {
> +	struct ufs_hba *hba;
> +	u8 mask;
> +};
> +
> +static int ufs_read_temp_enable(struct ufs_hba *hba, u8 mask, long *val)
> +{
> +	u32 ee_mask;
> +	int err;
> +
> +	err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, QUERY_ATTR_IDN_EE_CONTROL, 0, 0,
> +				&ee_mask);
> +	if (err)
> +		return err;
> +
> +	*val = (mask & ee_mask & MASK_EE_TOO_HIGH_TEMP) || (mask & ee_mask & MASK_EE_TOO_LOW_TEMP);
> +
> +	return 0;
> +}
> +
> +static int ufs_get_temp(struct ufs_hba *hba, enum attr_idn idn, long *val)
> +{
> +	u32 value;
> +	int err;
> +
> +	err = ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, idn, 0, 0, &value);
> +	if (err)
> +		return err;
> +
> +	if (value == 0)
> +		return -ENODATA;
> +
> +	*val = ((long)value - 80) * MILLIDEGREE_PER_DEGREE;
> +
> +	return 0;
> +}
> +
> +static int ufs_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
> +			  long *val)
> +{
> +	struct ufs_hwmon_data *data = dev_get_drvdata(dev);
> +	struct ufs_hba *hba = data->hba;
> +	int err;
> +
> +	down(&hba->host_sem);
> +
> +	if (!ufshcd_is_user_access_allowed(hba)) {
> +		up(&hba->host_sem);
> +		return -EBUSY;
> +	}
> +
> +	ufshcd_rpm_get_sync(hba);
> +
> +	switch (attr) {
> +	case hwmon_temp_enable:
> +		err = ufs_read_temp_enable(hba, data->mask, val);
> +
> +		break;
> +	case hwmon_temp_crit:
> +		err = ufs_get_temp(hba, QUERY_ATTR_IDN_HIGH_TEMP_BOUND, val);
> +
> +		break;
> +	case hwmon_temp_lcrit:
> +		err = ufs_get_temp(hba, QUERY_ATTR_IDN_LOW_TEMP_BOUND, val);
> +
> +		break;
> +	case hwmon_temp_input:
> +		err = ufs_get_temp(hba, QUERY_ATTR_IDN_CASE_ROUGH_TEMP, val);
> +
> +		break;
> +	default:
> +		err = -EOPNOTSUPP;
> +
> +		break;
> +	}
> +
> +	ufshcd_rpm_put_sync(hba);
> +
> +	up(&hba->host_sem);
> +
> +	return err;
> +}
> +
> +static int ufs_hwmon_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
> +			   long val)
> +{
> +	struct ufs_hwmon_data *data = dev_get_drvdata(dev);
> +	struct ufs_hba *hba = data->hba;
> +	int err;
> +
> +	if (attr != hwmon_temp_enable)
> +		return -EINVAL;
> +
> +	if (val != 0 && val != 1)
> +		return -EINVAL;
> +
> +	down(&hba->host_sem);
> +
> +	if (!ufshcd_is_user_access_allowed(hba)) {
> +		up(&hba->host_sem);
> +		return -EBUSY;
> +	}
> +
> +	ufshcd_rpm_get_sync(hba);
> +
> +	if (val == 1)
> +		err = ufshcd_update_ee_usr_mask(hba, MASK_EE_URGENT_TEMP, 0);
> +	else
> +		err = ufshcd_update_ee_usr_mask(hba, 0, MASK_EE_URGENT_TEMP);
> +
> +	ufshcd_rpm_put_sync(hba);
> +
> +	up(&hba->host_sem);
> +
> +	return err;
> +}
> +
> +static umode_t ufs_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr,
> +				    int channel)
> +{
> +	if (type != hwmon_temp)
> +		return 0;
> +
> +	switch (attr) {
> +	case hwmon_temp_enable:
> +		return 0644;
> +	case hwmon_temp_crit:
> +	case hwmon_temp_lcrit:
> +	case hwmon_temp_input:
> +		return 0444;
> +	default:
> +		break;
> +	}
> +	return 0;
> +}
> +
> +static const struct hwmon_channel_info *ufs_hwmon_info[] = {
> +	HWMON_CHANNEL_INFO(temp, HWMON_T_ENABLE | HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_LCRIT),
> +	NULL
> +};
> +
> +static const struct hwmon_ops ufs_hwmon_ops = {
> +	.is_visible	= ufs_hwmon_is_visible,
> +	.read		= ufs_hwmon_read,
> +	.write		= ufs_hwmon_write,
> +};
> +
> +static const struct hwmon_chip_info ufs_hwmon_hba_info = {
> +	.ops	= &ufs_hwmon_ops,
> +	.info	= ufs_hwmon_info,
> +};
> +
> +void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask)
> +{
> +	struct device *dev = hba->dev;
> +	struct ufs_hwmon_data *data;
> +	struct device *hwmon;
> +
> +	data = kzalloc(sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return;
> +
> +	data->hba = hba;
> +	data->mask = mask;
> +
> +	hwmon = hwmon_device_register_with_info(dev, "ufs", data, &ufs_hwmon_hba_info, NULL);
> +	if (IS_ERR(hwmon)) {
> +		dev_warn(dev, "Failed to instantiate hwmon device\n");
> +		kfree(data);
> +		return;
> +	}
> +
> +	hba->hwmon_device = hwmon;
> +}
> +
> +void ufs_hwmon_remove(struct ufs_hba *hba)
> +{
> +	struct ufs_hwmon_data *data;
> +
> +	if (!hba->hwmon_device)
> +		return;
> +
> +	data = dev_get_drvdata(hba->hwmon_device);
> +	hwmon_device_unregister(hba->hwmon_device);
> +	hba->hwmon_device = NULL;
> +	kfree(data);
> +}
> diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
> index 8c6b38b1b142..0bfdca3e648e 100644
> --- a/drivers/scsi/ufs/ufs.h
> +++ b/drivers/scsi/ufs/ufs.h
> @@ -152,6 +152,9 @@ enum attr_idn {
>  	QUERY_ATTR_IDN_PSA_STATE		= 0x15,
>  	QUERY_ATTR_IDN_PSA_DATA_SIZE		= 0x16,
>  	QUERY_ATTR_IDN_REF_CLK_GATING_WAIT_TIME	= 0x17,
> +	QUERY_ATTR_IDN_CASE_ROUGH_TEMP          = 0x18,
> +	QUERY_ATTR_IDN_HIGH_TEMP_BOUND          = 0x19,
> +	QUERY_ATTR_IDN_LOW_TEMP_BOUND           = 0x1A,
>  	QUERY_ATTR_IDN_WB_FLUSH_STATUS	        = 0x1C,
>  	QUERY_ATTR_IDN_AVAIL_WB_BUFF_SIZE       = 0x1D,
>  	QUERY_ATTR_IDN_WB_BUFF_LIFE_TIME_EST    = 0x1E,
> @@ -338,6 +341,9 @@ enum {
>  
>  /* Possible values for dExtendedUFSFeaturesSupport */
>  enum {
> +	UFS_DEV_LOW_TEMP_NOTIF		= BIT(4),
> +	UFS_DEV_HIGH_TEMP_NOTIF		= BIT(5),
> +	UFS_DEV_EXT_TEMP_NOTIF		= BIT(6),
>  	UFS_DEV_HPB_SUPPORT		= BIT(7),
>  	UFS_DEV_WRITE_BOOSTER_SUP	= BIT(8),
>  };
> @@ -370,6 +376,7 @@ enum {
>  	MASK_EE_WRITEBOOSTER_EVENT	= BIT(5),
>  	MASK_EE_PERFORMANCE_THROTTLING	= BIT(6),
>  };
> +#define MASK_EE_URGENT_TEMP (MASK_EE_TOO_HIGH_TEMP | MASK_EE_TOO_LOW_TEMP)
>  
>  /* Background operation status */
>  enum bkops_status {
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 3841ab49f556..ce22340024ce 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -7469,6 +7469,29 @@ static void ufshcd_wb_probe(struct ufs_hba *hba, u8 *desc_buf)
>  	hba->caps &= ~UFSHCD_CAP_WB_EN;
>  }
>  
> +static void ufshcd_temp_notif_probe(struct ufs_hba *hba, u8 *desc_buf)
> +{
> +	struct ufs_dev_info *dev_info = &hba->dev_info;
> +	u32 ext_ufs_feature;
> +	u8 mask = 0;
> +
> +	if (!(hba->caps & UFSHCD_CAP_TEMP_NOTIF) || dev_info->wspecversion < 0x300)
> +		return;
> +
> +	ext_ufs_feature = get_unaligned_be32(desc_buf + DEVICE_DESC_PARAM_EXT_UFS_FEATURE_SUP);
> +
> +	if (ext_ufs_feature & UFS_DEV_LOW_TEMP_NOTIF)
> +		mask |= MASK_EE_TOO_LOW_TEMP;
> +
> +	if (ext_ufs_feature & UFS_DEV_HIGH_TEMP_NOTIF)
> +		mask |= MASK_EE_TOO_HIGH_TEMP;
> +
> +	if (mask) {
> +		ufshcd_enable_ee(hba, mask);
> +		ufs_hwmon_probe(hba, mask);
> +	}
> +}
> +
>  void ufshcd_fixup_dev_quirks(struct ufs_hba *hba, struct ufs_dev_fix *fixups)
>  {
>  	struct ufs_dev_fix *f;
> @@ -7564,6 +7587,8 @@ static int ufs_get_device_desc(struct ufs_hba *hba)
>  
>  	ufshcd_wb_probe(hba, desc_buf);
>  
> +	ufshcd_temp_notif_probe(hba, desc_buf);
> +
>  	/*
>  	 * ufshcd_read_string_desc returns size of the string
>  	 * reset the error value
> @@ -9408,6 +9433,7 @@ void ufshcd_remove(struct ufs_hba *hba)
>  {
>  	if (hba->sdev_ufs_device)
>  		ufshcd_rpm_get_sync(hba);
> +	ufs_hwmon_remove(hba);
>  	ufs_bsg_remove(hba);
>  	ufshpb_remove(hba);
>  	ufs_sysfs_remove_nodes(hba->dev);
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 52ea6f350b18..021c858955af 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -653,6 +653,12 @@ enum ufshcd_caps {
>  	 * in order to exit DeepSleep state.
>  	 */
>  	UFSHCD_CAP_DEEPSLEEP				= 1 << 10,
> +
> +	/*
> +	 * This capability allows the host controller driver to use temperature
> +	 * notification if it is supported by the UFS device.
> +	 */
> +	UFSHCD_CAP_TEMP_NOTIF				= 1 << 11,
>  };
>  
>  struct ufs_hba_variant_params {
> @@ -789,6 +795,10 @@ struct ufs_hba {
>  	struct scsi_device *sdev_ufs_device;
>  	struct scsi_device *sdev_rpmb;
>  
> +#ifdef CONFIG_SCSI_UFS_HWMON
> +	struct device *hwmon_device;
> +#endif
> +
>  	enum ufs_dev_pwr_mode curr_dev_pwr_mode;
>  	enum uic_link_state uic_link_state;
>  	/* Desired UFS power management level during runtime PM */
> @@ -1049,6 +1059,14 @@ static inline u8 ufshcd_wb_get_query_index(struct ufs_hba *hba)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_SCSI_UFS_HWMON
> +void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask);
> +void ufs_hwmon_remove(struct ufs_hba *hba);
> +#else
> +static inline void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask) {}
> +static inline void ufs_hwmon_remove(struct ufs_hba *hba) {}
> +#endif
> +
>  #ifdef CONFIG_PM
>  extern int ufshcd_runtime_suspend(struct device *dev);
>  extern int ufshcd_runtime_resume(struct device *dev);
> -- 
> 2.17.1
> 

Re: [PATCH v7 2/2] scsi: ufs: Add temperature notification exception handling

[Guenter Roeck]

On Wed, Sep 15, 2021 at 09:04:07AM +0300, Avri Altman wrote:
> The device may notify the host of an extreme temperature by using the
> exception event mechanism. The exception can be raised when the device’s
> Tcase temperature is either too high or too low.
> 
> It is essentially up to the platform to decide what further actions need
> to be taken. leave a placeholder for a designated vop for that.
> 
> Signed-off-by: Avri Altman <avri.altman@wdc.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> ---
>  drivers/scsi/ufs/ufs-hwmon.c | 12 ++++++++++++
>  drivers/scsi/ufs/ufshcd.c    | 21 +++++++++++++++++++++
>  drivers/scsi/ufs/ufshcd.h    |  2 ++
>  3 files changed, 35 insertions(+)
> 
> diff --git a/drivers/scsi/ufs/ufs-hwmon.c b/drivers/scsi/ufs/ufs-hwmon.c
> index 33b66736aaa4..74855491dc8f 100644
> --- a/drivers/scsi/ufs/ufs-hwmon.c
> +++ b/drivers/scsi/ufs/ufs-hwmon.c
> @@ -196,3 +196,15 @@ void ufs_hwmon_remove(struct ufs_hba *hba)
>  	hba->hwmon_device = NULL;
>  	kfree(data);
>  }
> +
> +void ufs_hwmon_notify_event(struct ufs_hba *hba, u8 ee_mask)
> +{
> +	if (!hba->hwmon_device)
> +		return;
> +
> +	if (ee_mask & MASK_EE_TOO_HIGH_TEMP)
> +		hwmon_notify_event(hba->hwmon_device, hwmon_temp, hwmon_temp_max_alarm, 0);
> +
> +	if (ee_mask & MASK_EE_TOO_LOW_TEMP)
> +		hwmon_notify_event(hba->hwmon_device, hwmon_temp, hwmon_temp_min_alarm, 0);
> +}
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index ce22340024ce..debef631c89a 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -5642,6 +5642,24 @@ static void ufshcd_bkops_exception_event_handler(struct ufs_hba *hba)
>  				__func__, err);
>  }
>  
> +static void ufshcd_temp_exception_event_handler(struct ufs_hba *hba, u16 status)
> +{
> +	u32 value;
> +
> +	if (ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
> +				QUERY_ATTR_IDN_CASE_ROUGH_TEMP, 0, 0, &value))
> +		return;
> +
> +	dev_info(hba->dev, "exception Tcase %d\n", value - 80);
> +
> +	ufs_hwmon_notify_event(hba, status & MASK_EE_URGENT_TEMP);
> +
> +	/*
> +	 * A placeholder for the platform vendors to add whatever additional
> +	 * steps required
> +	 */
> +}
> +
>  static int __ufshcd_wb_toggle(struct ufs_hba *hba, bool set, enum flag_idn idn)
>  {
>  	u8 index;
> @@ -5821,6 +5839,9 @@ static void ufshcd_exception_event_handler(struct work_struct *work)
>  	if (status & hba->ee_drv_mask & MASK_EE_URGENT_BKOPS)
>  		ufshcd_bkops_exception_event_handler(hba);
>  
> +	if (status & hba->ee_drv_mask & MASK_EE_URGENT_TEMP)
> +		ufshcd_temp_exception_event_handler(hba, status);
> +
>  	ufs_debugfs_exception_event(hba, status);
>  out:
>  	ufshcd_scsi_unblock_requests(hba);
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 021c858955af..92d05329de68 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -1062,9 +1062,11 @@ static inline u8 ufshcd_wb_get_query_index(struct ufs_hba *hba)
>  #ifdef CONFIG_SCSI_UFS_HWMON
>  void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask);
>  void ufs_hwmon_remove(struct ufs_hba *hba);
> +void ufs_hwmon_notify_event(struct ufs_hba *hba, u8 ee_mask);
>  #else
>  static inline void ufs_hwmon_probe(struct ufs_hba *hba, u8 mask) {}
>  static inline void ufs_hwmon_remove(struct ufs_hba *hba) {}
> +static inline void ufs_hwmon_notify_event(struct ufs_hba *hba, u8 ee_mask) {}
>  #endif
>  
>  #ifdef CONFIG_PM
> -- 
> 2.17.1
> 

Re: [PATCH v7 1/2] scsi: ufs: Probe for temperature notification support

[Bean Huo]

On Wed, 2021-09-15 at 09:04 +0300, Avri Altman wrote:
> Probe the dExtendedUFSFeaturesSupport register for the device's
> 
> temperature notification support, and if supported, add a hw monitor
> 
> device.
> 
> 
> 
> Signed-off-by: Avri Altman <avri.altman@wdc.com>

Thanks!

Reviewed-by: Bean Huo <beanhuo@micron.com>

Re: [PATCH v7 2/2] scsi: ufs: Add temperature notification exception handling

[Bean Huo]

On Wed, 2021-09-15 at 09:04 +0300, Avri Altman wrote:
> The device may notify the host of an extreme temperature by using the
> 
> exception event mechanism. The exception can be raised when the
> device’s
> 
> Tcase temperature is either too high or too low.
> 
> 
> 
> It is essentially up to the platform to decide what further actions
> need
> 
> to be taken. leave a placeholder for a designated vop for that.
> 
> 
> 
> Signed-off-by: Avri Altman <avri.altman@wdc.com>

Reviewed-by: Bean Huo <beanhuo@micron.com>

RE: [PATCH v7 1/2] scsi: ufs: Probe for temperature notification support

[Daejun Park]

Hi Avri,

>+config SCSI_UFS_HWMON
>+        bool "UFS  Temperature Notification"
It has double space.

>+        depends on SCSI_UFSHCD && HWMON
>+        help
>+          This provides support for UFS hardware monitoring. If enabled,
>+          a hardware monitoring device will be created for the UFS device.
>+
>+          If unsure, say N.

Anyway,
Reviewed-by: Daejun Park <daejun7.park@samsung.com>

Thanks,
Daejun

RE: [PATCH v7 2/2] scsi: ufs: Add temperature notification exception handling

[Daejun Park]

Hi Avri,

>The device may notify the host of an extreme temperature by using the
>exception event mechanism. The exception can be raised when the device’s
>Tcase temperature is either too high or too low.
> 
>It is essentially up to the platform to decide what further actions need
>to be taken. leave a placeholder for a designated vop for that.
> 
>Signed-off-by: Avri Altman <avri.altman@wdc.com>

Reviewed-by: Daejun Park <daejun7.park@samsung.com>

Re: [PATCH v7 0/2] Add temperature notification support

[Martin K. Petersen]

Avri,

> UFS3.0 allows using the ufs device as a temperature sensor. The purpose
> of this optional feature is to provide notification to the host of the
> UFS device case temperature. It allows reading of a rough estimate
> (+-10 degrees centigrade) of the current case temperature, and setting a
> lower and upper temperature bounds, in which the device will trigger an
> applicable exception event.

Applied to 5.16/scsi-staging, thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering

Re: [PATCH v7 0/2] Add temperature notification support

[Martin K. Petersen]

On Wed, 15 Sep 2021 09:04:05 +0300, Avri Altman wrote:

> v6 -> v7:
>  - some more useless initializations
> 
> v5 -> v6:
>  - remove useless initializations
> 
> v4 - > v5:
>  - Fix improper return error values
> 
> [...]

Applied to 5.16/scsi-queue, thanks!

[1/2] scsi: ufs: Probe for temperature notification support
      https://git.kernel.org/mkp/scsi/c/e88e2d32200a
[2/2] scsi: ufs: Add temperature notification exception handling
      https://git.kernel.org/mkp/scsi/c/322c4b29ee1f

-- 
Martin K. Petersen	Oracle Linux Engineering