diff options
Diffstat (limited to 'drivers/nvme/host/hwmon.c')
-rw-r--r-- | drivers/nvme/host/hwmon.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/nvme/host/hwmon.c b/drivers/nvme/host/hwmon.c new file mode 100644 index 000000000000..a5af21f5d370 --- /dev/null +++ b/drivers/nvme/host/hwmon.c @@ -0,0 +1,259 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * NVM Express hardware monitoring support + * Copyright (c) 2019, Guenter Roeck + */ + +#include <linux/hwmon.h> +#include <asm/unaligned.h> + +#include "nvme.h" + +/* These macros should be moved to linux/temperature.h */ +#define MILLICELSIUS_TO_KELVIN(t) DIV_ROUND_CLOSEST((t) + 273150, 1000) +#define KELVIN_TO_MILLICELSIUS(t) ((t) * 1000L - 273150) + +struct nvme_hwmon_data { + struct nvme_ctrl *ctrl; + struct nvme_smart_log log; + struct mutex read_lock; +}; + +static int nvme_get_temp_thresh(struct nvme_ctrl *ctrl, int sensor, bool under, + long *temp) +{ + unsigned int threshold = sensor << NVME_TEMP_THRESH_SELECT_SHIFT; + u32 status; + int ret; + + if (under) + threshold |= NVME_TEMP_THRESH_TYPE_UNDER; + + ret = nvme_get_features(ctrl, NVME_FEAT_TEMP_THRESH, threshold, NULL, 0, + &status); + if (ret > 0) + return -EIO; + if (ret < 0) + return ret; + *temp = KELVIN_TO_MILLICELSIUS(status & NVME_TEMP_THRESH_MASK); + + return 0; +} + +static int nvme_set_temp_thresh(struct nvme_ctrl *ctrl, int sensor, bool under, + long temp) +{ + unsigned int threshold = sensor << NVME_TEMP_THRESH_SELECT_SHIFT; + int ret; + + temp = MILLICELSIUS_TO_KELVIN(temp); + threshold |= clamp_val(temp, 0, NVME_TEMP_THRESH_MASK); + + if (under) + threshold |= NVME_TEMP_THRESH_TYPE_UNDER; + + ret = nvme_set_features(ctrl, NVME_FEAT_TEMP_THRESH, threshold, NULL, 0, + NULL); + if (ret > 0) + return -EIO; + + return ret; +} + +static int nvme_hwmon_get_smart_log(struct nvme_hwmon_data *data) +{ + int ret; + + ret = nvme_get_log(data->ctrl, NVME_NSID_ALL, NVME_LOG_SMART, 0, + &data->log, sizeof(data->log), 0); + + return ret <= 0 ? ret : -EIO; +} + +static int nvme_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct nvme_hwmon_data *data = dev_get_drvdata(dev); + struct nvme_smart_log *log = &data->log; + int temp; + int err; + + /* + * First handle attributes which don't require us to read + * the smart log. + */ + switch (attr) { + case hwmon_temp_max: + return nvme_get_temp_thresh(data->ctrl, channel, false, val); + case hwmon_temp_min: + return nvme_get_temp_thresh(data->ctrl, channel, true, val); + case hwmon_temp_crit: + *val = KELVIN_TO_MILLICELSIUS(data->ctrl->cctemp); + return 0; + default: + break; + } + + mutex_lock(&data->read_lock); + err = nvme_hwmon_get_smart_log(data); + if (err) + goto unlock; + + switch (attr) { + case hwmon_temp_input: + if (!channel) + temp = get_unaligned_le16(log->temperature); + else + temp = le16_to_cpu(log->temp_sensor[channel - 1]); + *val = KELVIN_TO_MILLICELSIUS(temp); + break; + case hwmon_temp_alarm: + *val = !!(log->critical_warning & NVME_SMART_CRIT_TEMPERATURE); + break; + default: + err = -EOPNOTSUPP; + break; + } +unlock: + mutex_unlock(&data->read_lock); + return err; +} + +static int nvme_hwmon_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + struct nvme_hwmon_data *data = dev_get_drvdata(dev); + + switch (attr) { + case hwmon_temp_max: + return nvme_set_temp_thresh(data->ctrl, channel, false, val); + case hwmon_temp_min: + return nvme_set_temp_thresh(data->ctrl, channel, true, val); + default: + break; + } + + return -EOPNOTSUPP; +} + +static const char * const nvme_hwmon_sensor_names[] = { + "Composite", + "Sensor 1", + "Sensor 2", + "Sensor 3", + "Sensor 4", + "Sensor 5", + "Sensor 6", + "Sensor 7", + "Sensor 8", +}; + +static int nvme_hwmon_read_string(struct device *dev, + enum hwmon_sensor_types type, u32 attr, + int channel, const char **str) +{ + *str = nvme_hwmon_sensor_names[channel]; + return 0; +} + +static umode_t nvme_hwmon_is_visible(const void *_data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + const struct nvme_hwmon_data *data = _data; + + switch (attr) { + case hwmon_temp_crit: + if (!channel && data->ctrl->cctemp) + return 0444; + break; + case hwmon_temp_max: + case hwmon_temp_min: + if ((!channel && data->ctrl->wctemp) || + (channel && data->log.temp_sensor[channel - 1])) { + if (data->ctrl->quirks & + NVME_QUIRK_NO_TEMP_THRESH_CHANGE) + return 0444; + return 0644; + } + break; + case hwmon_temp_alarm: + if (!channel) + return 0444; + break; + case hwmon_temp_input: + case hwmon_temp_label: + if (!channel || data->log.temp_sensor[channel - 1]) + return 0444; + break; + default: + break; + } + return 0; +} + +static const struct hwmon_channel_info *nvme_hwmon_info[] = { + HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_CRIT | HWMON_T_LABEL | HWMON_T_ALARM, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL, + HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN | + HWMON_T_LABEL), + NULL +}; + +static const struct hwmon_ops nvme_hwmon_ops = { + .is_visible = nvme_hwmon_is_visible, + .read = nvme_hwmon_read, + .read_string = nvme_hwmon_read_string, + .write = nvme_hwmon_write, +}; + +static const struct hwmon_chip_info nvme_hwmon_chip_info = { + .ops = &nvme_hwmon_ops, + .info = nvme_hwmon_info, +}; + +void nvme_hwmon_init(struct nvme_ctrl *ctrl) +{ + struct device *dev = ctrl->dev; + struct nvme_hwmon_data *data; + struct device *hwmon; + int err; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return; + + data->ctrl = ctrl; + mutex_init(&data->read_lock); + + err = nvme_hwmon_get_smart_log(data); + if (err) { + dev_warn(dev, "Failed to read smart log (error %d)\n", err); + devm_kfree(dev, data); + return; + } + + hwmon = devm_hwmon_device_register_with_info(dev, "nvme", data, + &nvme_hwmon_chip_info, + NULL); + if (IS_ERR(hwmon)) { + dev_warn(dev, "Failed to instantiate hwmon device\n"); + devm_kfree(dev, data); + } +} |