[PATCH v3 1/2] scsi: ufs: Probe for temperature notification support

From: Avri Altman
Date: Sun Sep 12 2021 - 09:19:41 EST


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 | 10 ++
drivers/scsi/ufs/Makefile | 1 +
drivers/scsi/ufs/ufs-hwmon.c | 179 +++++++++++++++++++++++++++++++++++
drivers/scsi/ufs/ufs.h | 6 ++
drivers/scsi/ufs/ufshcd.c | 28 ++++++
drivers/scsi/ufs/ufshcd.h | 18 ++++
6 files changed, 242 insertions(+)
create mode 100644 drivers/scsi/ufs/ufs-hwmon.c

diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
index 432df76e6318..b930f29fc375 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -199,3 +199,13 @@ 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..a50e83f645f4
--- /dev/null
+++ b/drivers/scsi/ufs/ufs-hwmon.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * UFS hardware monitoring support
+ * Copyright (c) 2021, Western Digital Corporation
+ */
+
+#include <linux/hwmon.h>
+
+#include "ufshcd.h"
+
+struct ufs_hwmon_data {
+ struct ufs_hba *hba;
+ u8 mask;
+};
+
+static bool ufs_temp_enabled(struct ufs_hba *hba, u8 mask)
+{
+ u32 ee_mask;
+
+ if (ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR,
+ QUERY_ATTR_IDN_EE_CONTROL, 0, 0, &ee_mask))
+ return false;
+
+ return (mask & ee_mask & MASK_EE_TOO_HIGH_TEMP) ||
+ (mask & ee_mask & MASK_EE_TOO_LOW_TEMP);
+}
+
+static bool ufs_temp_valid(struct ufs_hba *hba, u8 mask,
+ enum attr_idn idn, u32 value)
+{
+ return (idn == QUERY_ATTR_IDN_CASE_ROUGH_TEMP && value >= 1 &&
+ value <= 250 && ufs_temp_enabled(hba, mask)) ||
+ (idn == QUERY_ATTR_IDN_HIGH_TEMP_BOUND && value >= 100 &&
+ value <= 250) ||
+ (idn == QUERY_ATTR_IDN_LOW_TEMP_BOUND && value >= 1 &&
+ value <= 80);
+}
+
+static int ufs_get_temp(struct ufs_hba *hba, u8 mask, enum attr_idn idn)
+{
+ u32 value;
+
+ if (ufshcd_query_attr(hba, UPIU_QUERY_OPCODE_READ_ATTR, idn, 0, 0,
+ &value))
+ return 0;
+
+ if (ufs_temp_valid(hba, mask, idn, value))
+ return value - 80;
+
+ 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;
+ u8 mask = data->mask;
+ int err = 0;
+ bool get_temp = true;
+
+ if (type != hwmon_temp)
+ return 0;
+
+ 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:
+ *val = ufs_temp_enabled(hba, mask);
+ get_temp = false;
+
+ break;
+ case hwmon_temp_max_alarm:
+ *val = ufs_get_temp(hba, mask, QUERY_ATTR_IDN_HIGH_TEMP_BOUND);
+
+ break;
+ case hwmon_temp_min_alarm:
+ *val = ufs_get_temp(hba, mask, QUERY_ATTR_IDN_LOW_TEMP_BOUND);
+
+ break;
+ case hwmon_temp_input:
+ *val = ufs_get_temp(hba, mask, QUERY_ATTR_IDN_CASE_ROUGH_TEMP);
+
+ break;
+ default:
+ err = -EOPNOTSUPP;
+
+ break;
+ }
+
+ ufshcd_rpm_put_sync(hba);
+
+ up(&hba->host_sem);
+
+ if (get_temp && !err && *val == 0)
+ err = -EINVAL;
+
+ 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:
+ case hwmon_temp_max_alarm:
+ case hwmon_temp_min_alarm:
+ 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_MIN_ALARM | HWMON_T_MAX_ALARM),
+ NULL
+};
+
+static const struct hwmon_ops ufs_hwmon_ops = {
+ .is_visible = ufs_hwmon_is_visible,
+ .read = ufs_hwmon_read,
+};
+
+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..171b27be7b1d 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),
};
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 67889d74761c..90c2e9677435 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -7469,6 +7469,31 @@ 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 +7589,8 @@ 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 +9435,7 @@ 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 4723f27a55d1..798a408d71e5 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 */
@@ -1050,6 +1060,14 @@ 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