Re: [PATCH v6 1/2] scsi: ufs: Probe for temperature notification support

From: Guenter Roeck
Date: Tue Sep 14 2021 - 16:54:28 EST

On 9/14/21 1:27 PM, 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@xxxxxxx>
---
drivers/scsi/ufs/Kconfig | 9 ++
drivers/scsi/ufs/Makefile | 1 +
drivers/scsi/ufs/ufs-hwmon.c | 201 +++++++++++++++++++++++++++++++++++
drivers/scsi/ufs/ufs.h | 7 ++
drivers/scsi/ufs/ufshcd.c | 26 +++++
drivers/scsi/ufs/ufshcd.h | 18 ++++
6 files changed, 262 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..fa8ac39f4444
--- /dev/null
+++ b/drivers/scsi/ufs/ufs-hwmon.c
@@ -0,0 +1,201 @@
+// 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;
+
+ if (type != hwmon_temp)
+ return 0;
+

Was that there before ? Dorry, I didn't notice.
First of all, strictly speaking it is unnecessary, but if it is there
it should return an error. Plus, checking the type here but not in
the write function is a bit inconsistent.

+ 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 = 0;

Still unnecessary.

+
+ 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);