Add support for SPD5118 (Jedec JESD300) compliant temperature sensors. Such sensors are typically found on DDR5 memory modules. Cc: René Rebe <rene@xxxxxxxxxxxx> Cc: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> Reviewed-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> Tested-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- v4: No change v3: Shorten JESD300-5B.01 to JESD300; 5B.01 refers to the version of the standard Drop unnecessary 'attr' parameter from spd5118_{read,write}_enable() v2: Drop PEC property documentation Add note indicating that alarm attributes are sticky until read to documentation Fix detect function Fix misspelling in Makefile (CONFIG_SENSORS_SPD5118->CONFIG_SENSORS_SPD5118) Documentation/hwmon/index.rst | 1 + Documentation/hwmon/spd5118.rst | 55 ++++ drivers/hwmon/Kconfig | 12 + drivers/hwmon/Makefile | 1 + drivers/hwmon/spd5118.c | 481 ++++++++++++++++++++++++++++++++ 5 files changed, 550 insertions(+) create mode 100644 Documentation/hwmon/spd5118.rst create mode 100644 drivers/hwmon/spd5118.c diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index 03d313af469a..6e7b8726b60c 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -215,6 +215,7 @@ Hardware Monitoring Kernel Drivers smsc47m192 smsc47m1 sparx5-temp + spd5118 stpddc60 surface_fan sy7636a-hwmon diff --git a/Documentation/hwmon/spd5118.rst b/Documentation/hwmon/spd5118.rst new file mode 100644 index 000000000000..a15d75aa2066 --- /dev/null +++ b/Documentation/hwmon/spd5118.rst @@ -0,0 +1,55 @@ +.. SPDX-License-Identifier: GPL-2.0-or-later + +Kernel driver spd5118 +===================== + +Supported chips: + + * SPD5118 (JEDEC JESD300) compliant temperature sensor chips + + JEDEC standard download: + https://www.jedec.org/standards-documents/docs/jesd300-5b01 + (account required) + + + Prefix: 'spd5118' + + Addresses scanned: I2C 0x50 - 0x57 + +Author: + Guenter Roeck <linux@xxxxxxxxxxxx> + + +Description +----------- + +This driver implements support for SPD5118 (JEDEC JESD300) compliant temperature +sensors, which are used on many DDR5 memory modules. Some systems use the sensor +to prevent memory overheating by automatically throttling the memory controller. + +The driver auto-detects SPD5118 compliant chips, but can also be instantiated +using devicetree/firmware nodes. + +A SPD5118 compliant chip supports a single temperature sensor. Critical minimum, +minimum, maximum, and critical temperature can be configured. There are alarms +for low critical, low, high, and critical thresholds. + + +Hardware monitoring sysfs entries +--------------------------------- + +======================= ================================== +temp1_input Temperature (RO) +temp1_lcrit Low critical high temperature (RW) +temp1_min Minimum temperature (RW) +temp1_max Maximum temperature (RW) +temp1_crit Critical high temperature (RW) + +temp1_lcrit_alarm Temperature low critical alarm +temp1_min_alarm Temperature low alarm +temp1_max_alarm Temperature high alarm +temp1_crit_alarm Temperature critical alarm +======================= ================================== + +Alarm attributes are sticky until read and will be cleared afterwards +unless the alarm condition still applies. diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index e14ae18a973b..7a84e7637b51 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -2181,6 +2181,18 @@ config SENSORS_INA3221 This driver can also be built as a module. If so, the module will be called ina3221. +config SENSORS_SPD5118 + tristate "SPD5118 Compliant Temperature Sensors" + depends on I2C + select REGMAP_I2C + help + If you say yes here you get support for SPD5118 (JEDEC JESD300) + compliant temperature sensors. Such sensors are found on DDR5 memory + modules. + + This driver can also be built as a module. If so, the module + will be called spd5118. + config SENSORS_TC74 tristate "Microchip TC74" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index e3f25475d1f0..6574ca67d761 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -207,6 +207,7 @@ obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o obj-$(CONFIG_SENSORS_SMSC47M1) += smsc47m1.o obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o obj-$(CONFIG_SENSORS_SPARX5) += sparx5-temp.o +obj-$(CONFIG_SENSORS_SPD5118) += spd5118.o obj-$(CONFIG_SENSORS_STTS751) += stts751.o obj-$(CONFIG_SENSORS_SURFACE_FAN)+= surface_fan.o obj-$(CONFIG_SENSORS_SY7636A) += sy7636a-hwmon.o diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c new file mode 100644 index 000000000000..d3fc0ae17743 --- /dev/null +++ b/drivers/hwmon/spd5118.c @@ -0,0 +1,481 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for Jedec 5118 compliant temperature sensors + * + * Derived from https://github.com/Steve-Tech/SPD5118-DKMS + * Originally from T/2 driver at https://t2sde.org/packages/linux + * Copyright (c) 2023 René Rebe, ExactCODE GmbH; Germany. + * + * Copyright (c) 2024 Guenter Roeck + * + * Inspired by ee1004.c and jc42.c. + * + * SPD5118 compliant temperature sensors are typically used on DDR5 + * memory modules. + */ + +#include <linux/bitops.h> +#include <linux/bits.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/hwmon.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/units.h> + +/* Addresses to scan */ +static const unsigned short normal_i2c[] = { + 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, I2C_CLIENT_END }; + +/* SPD5118 registers. */ +#define SPD5118_REG_TYPE 0x00 /* MR0:MR1 */ +#define SPD5118_REG_REVISION 0x02 /* MR2 */ +#define SPD5118_REG_VENDOR 0x03 /* MR3:MR4 */ +#define SPD5118_REG_CAPABILITY 0x05 /* MR5 */ +#define SPD5118_REG_I2C_LEGACY_MODE 0x0B /* MR11 */ +#define SPD5118_REG_TEMP_CLR 0x13 /* MR19 */ +#define SPD5118_REG_ERROR_CLR 0x14 /* MR20 */ +#define SPD5118_REG_TEMP_CONFIG 0x1A /* MR26 */ +#define SPD5118_REG_TEMP_MAX 0x1c /* MR28:MR29 */ +#define SPD5118_REG_TEMP_MIN 0x1e /* MR30:MR31 */ +#define SPD5118_REG_TEMP_CRIT 0x20 /* MR32:MR33 */ +#define SPD5118_REG_TEMP_LCRIT 0x22 /* MR34:MR35 */ +#define SPD5118_REG_TEMP 0x31 /* MR49:MR50 */ +#define SPD5118_REG_TEMP_STATUS 0x33 /* MR51 */ + +#define SPD5118_TEMP_STATUS_HIGH BIT(0) +#define SPD5118_TEMP_STATUS_LOW BIT(1) +#define SPD5118_TEMP_STATUS_CRIT BIT(2) +#define SPD5118_TEMP_STATUS_LCRIT BIT(3) + +#define SPD5118_CAP_TS_SUPPORT BIT(1) /* temperature sensor support */ + +#define SPD5118_TS_DISABLE BIT(0) /* temperature sensor disable */ + +/* Temperature unit in millicelsius */ +#define SPD5118_TEMP_UNIT (MILLIDEGREE_PER_DEGREE / 4) +/* Representable temperature range in millicelsius */ +#define SPD5118_TEMP_RANGE_MIN -256000 +#define SPD5118_TEMP_RANGE_MAX 255750 + +static int spd5118_temp_from_reg(u16 reg) +{ + int temp = sign_extend32(reg >> 2, 10); + + return temp * SPD5118_TEMP_UNIT; +} + +static u16 spd5118_temp_to_reg(long temp) +{ + temp = clamp_val(temp, SPD5118_TEMP_RANGE_MIN, SPD5118_TEMP_RANGE_MAX); + return (DIV_ROUND_CLOSEST(temp, SPD5118_TEMP_UNIT) & 0x7ff) << 2; +} + +static int spd5118_read_temp(struct regmap *regmap, u32 attr, long *val) +{ + int reg, err; + u8 regval[2]; + u16 temp; + + switch (attr) { + case hwmon_temp_input: + reg = SPD5118_REG_TEMP; + break; + case hwmon_temp_max: + reg = SPD5118_REG_TEMP_MAX; + break; + case hwmon_temp_min: + reg = SPD5118_REG_TEMP_MIN; + break; + case hwmon_temp_crit: + reg = SPD5118_REG_TEMP_CRIT; + break; + case hwmon_temp_lcrit: + reg = SPD5118_REG_TEMP_LCRIT; + break; + default: + return -EOPNOTSUPP; + } + + err = regmap_bulk_read(regmap, reg, regval, 2); + if (err) + return err; + + temp = (regval[1] << 8) | regval[0]; + + *val = spd5118_temp_from_reg(temp); + return 0; +} + +static int spd5118_read_alarm(struct regmap *regmap, u32 attr, long *val) +{ + unsigned int mask, regval; + int err; + + switch (attr) { + case hwmon_temp_max_alarm: + mask = SPD5118_TEMP_STATUS_HIGH; + break; + case hwmon_temp_min_alarm: + mask = SPD5118_TEMP_STATUS_LOW; + break; + case hwmon_temp_crit_alarm: + mask = SPD5118_TEMP_STATUS_CRIT; + break; + case hwmon_temp_lcrit_alarm: + mask = SPD5118_TEMP_STATUS_LCRIT; + break; + default: + return -EOPNOTSUPP; + } + + err = regmap_read(regmap, SPD5118_REG_TEMP_STATUS, ®val); + if (err < 0) + return err; + *val = !!(regval & mask); + if (*val) + return regmap_write(regmap, SPD5118_REG_TEMP_CLR, mask); + return 0; +} + +static int spd5118_read_enable(struct regmap *regmap, long *val) +{ + u32 regval; + int err; + + err = regmap_read(regmap, SPD5118_REG_TEMP_CONFIG, ®val); + if (err < 0) + return err; + *val = !(regval & SPD5118_TS_DISABLE); + return 0; +} + +static int spd5118_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct regmap *regmap = dev_get_drvdata(dev); + + if (type != hwmon_temp) + return -EOPNOTSUPP; + + switch (attr) { + case hwmon_temp_input: + case hwmon_temp_max: + case hwmon_temp_min: + case hwmon_temp_crit: + case hwmon_temp_lcrit: + return spd5118_read_temp(regmap, attr, val); + case hwmon_temp_max_alarm: + case hwmon_temp_min_alarm: + case hwmon_temp_crit_alarm: + case hwmon_temp_lcrit_alarm: + return spd5118_read_alarm(regmap, attr, val); + case hwmon_temp_enable: + return spd5118_read_enable(regmap, val); + default: + return -EOPNOTSUPP; + } +} + +static int spd5118_write_temp(struct regmap *regmap, u32 attr, long val) +{ + u8 regval[2]; + u16 temp; + int reg; + + switch (attr) { + case hwmon_temp_max: + reg = SPD5118_REG_TEMP_MAX; + break; + case hwmon_temp_min: + reg = SPD5118_REG_TEMP_MIN; + break; + case hwmon_temp_crit: + reg = SPD5118_REG_TEMP_CRIT; + break; + case hwmon_temp_lcrit: + reg = SPD5118_REG_TEMP_LCRIT; + break; + default: + return -EOPNOTSUPP; + } + + temp = spd5118_temp_to_reg(val); + regval[0] = temp & 0xff; + regval[1] = temp >> 8; + + return regmap_bulk_write(regmap, reg, regval, 2); +} + +static int spd5118_write_enable(struct regmap *regmap, long val) +{ + if (val && val != 1) + return -EINVAL; + + return regmap_update_bits(regmap, SPD5118_REG_TEMP_CONFIG, + SPD5118_TS_DISABLE, + val ? 0 : SPD5118_TS_DISABLE); +} + +static int spd5118_temp_write(struct regmap *regmap, u32 attr, long val) +{ + switch (attr) { + case hwmon_temp_max: + case hwmon_temp_min: + case hwmon_temp_crit: + case hwmon_temp_lcrit: + return spd5118_write_temp(regmap, attr, val); + case hwmon_temp_enable: + return spd5118_write_enable(regmap, val); + default: + return -EOPNOTSUPP; + } +} + +static int spd5118_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + struct regmap *regmap = dev_get_drvdata(dev); + + switch (type) { + case hwmon_temp: + return spd5118_temp_write(regmap, attr, val); + default: + return -EOPNOTSUPP; + } +} + +static umode_t spd5118_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_input: + return 0444; + case hwmon_temp_min: + case hwmon_temp_max: + case hwmon_temp_lcrit: + case hwmon_temp_crit: + case hwmon_temp_enable: + return 0644; + case hwmon_temp_min_alarm: + case hwmon_temp_max_alarm: + case hwmon_temp_crit_alarm: + case hwmon_temp_lcrit_alarm: + return 0444; + default: + return 0; + } +} + +static inline bool spd5118_parity8(u8 w) +{ + w ^= w >> 4; + return (0x6996 >> (w & 0xf)) & 1; +} + +/* + * Bank and vendor id are 8-bit fields with seven data bits and odd parity. + * Vendor IDs 0 and 0x7f are invalid. + * See Jedec standard JEP106BJ for details and a list of assigned vendor IDs. + */ +static bool spd5118_vendor_valid(u8 bank, u8 id) +{ + if (!spd5118_parity8(bank) || !spd5118_parity8(id)) + return false; + + id &= 0x7f; + return id && id != 0x7f; +} + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int spd5118_detect(struct i2c_client *client, struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = client->adapter; + int regval; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + + regval = i2c_smbus_read_word_swapped(client, SPD5118_REG_TYPE); + if (regval != 0x5118) + return -ENODEV; + + regval = i2c_smbus_read_word_data(client, SPD5118_REG_VENDOR); + if (regval < 0 || !spd5118_vendor_valid(regval & 0xff, regval >> 8)) + return -ENODEV; + + regval = i2c_smbus_read_byte_data(client, SPD5118_REG_CAPABILITY); + if (regval < 0) + return -ENODEV; + if (!(regval & SPD5118_CAP_TS_SUPPORT) || (regval & 0xfc)) + return -ENODEV; + + regval = i2c_smbus_read_byte_data(client, SPD5118_REG_TEMP_CLR); + if (regval) + return -ENODEV; + regval = i2c_smbus_read_byte_data(client, SPD5118_REG_ERROR_CLR); + if (regval) + return -ENODEV; + + regval = i2c_smbus_read_byte_data(client, SPD5118_REG_REVISION); + if (regval < 0 || (regval & 0xc1)) + return -ENODEV; + + regval = i2c_smbus_read_byte_data(client, SPD5118_REG_TEMP_CONFIG); + if (regval < 0) + return -ENODEV; + if (regval & ~SPD5118_TS_DISABLE) + return -ENODEV; + + strscpy(info->type, "spd5118", I2C_NAME_SIZE); + return 0; +} + +static const struct hwmon_channel_info *spd5118_info[] = { + HWMON_CHANNEL_INFO(chip, + HWMON_C_REGISTER_TZ), + HWMON_CHANNEL_INFO(temp, + HWMON_T_INPUT | + HWMON_T_LCRIT | HWMON_T_LCRIT_ALARM | + HWMON_T_MIN | HWMON_T_MIN_ALARM | + HWMON_T_MAX | HWMON_T_MAX_ALARM | + HWMON_T_CRIT | HWMON_T_CRIT_ALARM | + HWMON_T_ENABLE), + NULL +}; + +static const struct hwmon_ops spd5118_hwmon_ops = { + .is_visible = spd5118_is_visible, + .read = spd5118_read, + .write = spd5118_write, +}; + +static const struct hwmon_chip_info spd5118_chip_info = { + .ops = &spd5118_hwmon_ops, + .info = spd5118_info, +}; + +static bool spd5118_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case SPD5118_REG_TEMP_CLR: + case SPD5118_REG_TEMP_CONFIG: + case SPD5118_REG_TEMP_MAX: + case SPD5118_REG_TEMP_MAX + 1: + case SPD5118_REG_TEMP_MIN: + case SPD5118_REG_TEMP_MIN + 1: + case SPD5118_REG_TEMP_CRIT: + case SPD5118_REG_TEMP_CRIT + 1: + case SPD5118_REG_TEMP_LCRIT: + case SPD5118_REG_TEMP_LCRIT + 1: + return true; + default: + return false; + } +} + +static bool spd5118_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case SPD5118_REG_TEMP_CLR: + case SPD5118_REG_ERROR_CLR: + case SPD5118_REG_TEMP: + case SPD5118_REG_TEMP + 1: + case SPD5118_REG_TEMP_STATUS: + return true; + default: + return false; + } +} + +static const struct regmap_config spd5118_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = SPD5118_REG_TEMP_STATUS, + .writeable_reg = spd5118_writeable_reg, + .volatile_reg = spd5118_volatile_reg, + .cache_type = REGCACHE_MAPLE, +}; + +static int spd5118_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + unsigned int regval, revision, vendor, bank; + struct device *hwmon_dev; + struct regmap *regmap; + int err; + + regmap = devm_regmap_init_i2c(client, &spd5118_regmap_config); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), "regmap init failed\n"); + + err = regmap_read(regmap, SPD5118_REG_CAPABILITY, ®val); + if (err) + return err; + if (!(regval & SPD5118_CAP_TS_SUPPORT)) + return -ENODEV; + + err = regmap_read(regmap, SPD5118_REG_REVISION, &revision); + if (err) + return err; + + err = regmap_read(regmap, SPD5118_REG_VENDOR, &bank); + if (err) + return err; + err = regmap_read(regmap, SPD5118_REG_VENDOR + 1, &vendor); + if (err) + return err; + if (!spd5118_vendor_valid(bank, vendor)) + return -ENODEV; + + hwmon_dev = devm_hwmon_device_register_with_info(dev, "spd5118", + regmap, &spd5118_chip_info, + NULL); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + /* + * From JESD300-5B + * MR2 bits [5:4]: Major revision, 1..4 + * MR2 bits [3:1]: Minor revision, 0..8? Probably a typo, assume 1..8 + */ + dev_info(dev, "DDR5 temperature sensor: vendor 0x%02x:0x%02x revision %d.%d\n", + bank & 0x7f, vendor, ((revision >> 4) & 0x03) + 1, ((revision >> 1) & 0x07) + 1); + + return 0; +} + +static const struct i2c_device_id spd5118_id[] = { + { "spd5118", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, spd5118_id); + +static const struct of_device_id spd5118_of_ids[] = { + { .compatible = "jedec,spd5118", }, + { } +}; +MODULE_DEVICE_TABLE(of, spd5118_of_ids); + +static struct i2c_driver spd5118_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "spd5118", + .of_match_table = spd5118_of_ids, + }, + .probe = spd5118_probe, + .id_table = spd5118_id, + .detect = spd5118_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(spd5118_driver); + +MODULE_AUTHOR("René Rebe <rene@xxxxxxxxxxxx>"); +MODULE_AUTHOR("Guenter Roeck <linux@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("SPD 5118 driver"); +MODULE_LICENSE("GPL"); -- 2.39.2