Re: [v4 09/11] drivers/hwmon: Add PECI cputemp driver

[Guenter Roeck]

On Mon, May 21, 2018 at 12:59:52PM -0700, Jae Hyun Yoo wrote:
> This commit adds PECI cputemp hwmon driver.
> 
> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>
> Reviewed-by: Haiyue Wang <haiyue.wang@xxxxxxxxxxxxxxx>
> Reviewed-by: James Feist <james.feist@xxxxxxxxxxxxxxx>
> Reviewed-by: Vernon Mauery <vernon.mauery@xxxxxxxxxxxxxxx>
> Cc: Alan Cox <alan@xxxxxxxxxxxxxxx>
> Cc: Andrew Jeffery <andrew@xxxxxxxx>
> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Cc: Jason M Biils <jason.m.bills@xxxxxxxxxxxxxxx>
> Cc: Joel Stanley <joel@xxxxxxxxx>
> Cc: Miguel Ojeda <miguel.ojeda.sandonis@xxxxxxxxx>
> Cc: Andrew Lunn <andrew@xxxxxxx>
> Cc: Stef van Os <stef.van.os@xxxxxxxxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/hwmon/Kconfig        |  14 ++
>  drivers/hwmon/Makefile       |   1 +
>  drivers/hwmon/peci-cputemp.c | 407 +++++++++++++++++++++++++++++++++++
>  drivers/hwmon/peci-hwmon.c   | 124 +++++++++++
>  drivers/hwmon/peci-hwmon.h   |  51 +++++
>  5 files changed, 597 insertions(+)
>  create mode 100644 drivers/hwmon/peci-cputemp.c
>  create mode 100644 drivers/hwmon/peci-hwmon.c
>  create mode 100644 drivers/hwmon/peci-hwmon.h
> 
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index f10840ad465c..8492586bb1e4 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1256,6 +1256,20 @@ config SENSORS_NCT7904
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called nct7904.
>  
> +config SENSORS_PECI_CPUTEMP
> +	tristate "PECI CPU temperature monitoring support"
> +	depends on OF
> +	depends on PECI
> +	help
> +	  If you say yes here you get support for the generic Intel PECI
> +	  cputemp driver which provides Digital Thermal Sensor (DTS) thermal
> +	  readings of the CPU package and CPU cores that are accessible using
> +	  the PECI Client Command Suite via the processor PECI client.
> +	  Check Documentation/hwmon/peci-cputemp for details.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called peci-cputemp.
> +
>  config SENSORS_NSA320
>  	tristate "ZyXEL NSA320 and compatible fan speed and temperature sensors"
>  	depends on GPIOLIB && OF
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index e7d52a36e6c4..d18b374a9000 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -136,6 +136,7 @@ obj-$(CONFIG_SENSORS_NCT7802)	+= nct7802.o
>  obj-$(CONFIG_SENSORS_NCT7904)	+= nct7904.o
>  obj-$(CONFIG_SENSORS_NSA320)	+= nsa320-hwmon.o
>  obj-$(CONFIG_SENSORS_NTC_THERMISTOR)	+= ntc_thermistor.o
> +obj-$(CONFIG_SENSORS_PECI_CPUTEMP)	+= peci-cputemp.o peci-hwmon.o
>  obj-$(CONFIG_SENSORS_PC87360)	+= pc87360.o
>  obj-$(CONFIG_SENSORS_PC87427)	+= pc87427.o
>  obj-$(CONFIG_SENSORS_PCF8591)	+= pcf8591.o
> diff --git a/drivers/hwmon/peci-cputemp.c b/drivers/hwmon/peci-cputemp.c
> new file mode 100644
> index 000000000000..49c5a862bb58
> --- /dev/null
> +++ b/drivers/hwmon/peci-cputemp.c
> @@ -0,0 +1,407 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2018 Intel Corporation
> +
> +#include <linux/hwmon.h>
> +#include <linux/jiffies.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +
> +#include "peci-hwmon.h"
> +
> +#define DEFAULT_CHANNEL_NUMS   4
> +#define CORETEMP_CHANNEL_NUMS  CORE_NUMS_MAX
> +#define CPUTEMP_CHANNEL_NUMS   (DEFAULT_CHANNEL_NUMS + CORETEMP_CHANNEL_NUMS)
> +
> +/* The RESOLVED_CORES register in PCU of a client CPU */
> +#define REG_RESOLVED_CORES_BUS      1
> +#define REG_RESOLVED_CORES_DEVICE   30
> +#define REG_RESOLVED_CORES_FUNCTION 3
> +#define REG_RESOLVED_CORES_OFFSET   0xB4
> +
> +struct temp_group {
> +	struct temp_data die;
> +	struct temp_data tcontrol;
> +	struct temp_data tthrottle;
> +	struct temp_data tjmax;
> +	struct temp_data core[CORETEMP_CHANNEL_NUMS];
> +};
> +
> +struct peci_cputemp {
> +	struct peci_client *client;
> +	struct device *dev;
> +	char name[PECI_NAME_SIZE];
> +	struct temp_group temp;
> +	u8 addr;
> +	uint cpu_no;
> +	const struct cpu_gen_info *gen_info;
> +	u32 core_mask;
> +	u32 temp_config[CPUTEMP_CHANNEL_NUMS + 1];
> +	uint config_idx;
> +	struct hwmon_channel_info temp_info;
> +	const struct hwmon_channel_info *info[2];
> +	struct hwmon_chip_info chip;
> +};
> +
> +enum cputemp_channels {
> +	channel_die,
> +	channel_tcontrol,
> +	channel_tthrottle,
> +	channel_tjmax,
> +	channel_core,
> +};
> +
> +static const u32 config_table[DEFAULT_CHANNEL_NUMS + 1] = {
> +	/* Die temperature */
> +	HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
> +	HWMON_T_CRIT_HYST,
> +
> +	/* Tcontrol temperature */
> +	HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_CRIT,
> +
> +	/* Tthrottle temperature */
> +	HWMON_T_LABEL | HWMON_T_INPUT,
> +
> +	/* Tjmax temperature */
> +	HWMON_T_LABEL | HWMON_T_INPUT,
> +
> +	/* Core temperature - for all core channels */
> +	HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
> +	HWMON_T_CRIT_HYST,
> +};
> +
> +static const char *cputemp_label[CPUTEMP_CHANNEL_NUMS] = {
> +	"Die",
> +	"Tcontrol",
> +	"Tthrottle",
> +	"Tjmax",
> +	"Core 0", "Core 1", "Core 2", "Core 3",
> +	"Core 4", "Core 5", "Core 6", "Core 7",
> +	"Core 8", "Core 9", "Core 10", "Core 11",
> +	"Core 12", "Core 13", "Core 14", "Core 15",
> +	"Core 16", "Core 17", "Core 18", "Core 19",
> +	"Core 20", "Core 21", "Core 22", "Core 23",
> +};
> +
> +static s32 ten_dot_six_to_millidegree(s32 val)
> +{
> +	return ((val ^ 0x8000) - 0x8000) * 1000 / 64;
> +}
> +
> +static int get_temp_targets(struct peci_cputemp *priv)
> +{
> +	s32 tthrottle_offset;
> +	s32 tcontrol_margin;
> +	u8  pkg_cfg[4];
> +	int rc;
> +
> +	/**
> +	 * Just use only the tcontrol marker to determine if target values need
> +	 * update.
> +	 */
> +	if (!peci_hwmon_need_update(&priv->temp.tcontrol))
> +		return 0;
> +
> +	rc = peci_hwmon_rd_pkg_cfg_cmd(priv->client->adapter, priv->addr,
> +				       MBX_INDEX_TEMP_TARGET, 0, pkg_cfg);
> +	if (rc)
> +		return rc;
> +
> +	priv->temp.tjmax.value = pkg_cfg[2] * 1000;
> +
> +	tcontrol_margin = pkg_cfg[1];
> +	tcontrol_margin = ((tcontrol_margin ^ 0x80) - 0x80) * 1000;
> +	priv->temp.tcontrol.value = priv->temp.tjmax.value - tcontrol_margin;
> +
> +	tthrottle_offset = (pkg_cfg[3] & 0x2f) * 1000;
> +	priv->temp.tthrottle.value = priv->temp.tjmax.value - tthrottle_offset;
> +
> +	peci_hwmon_mark_updated(&priv->temp.tcontrol);
> +
> +	return 0;
> +}
> +
> +static int get_die_temp(struct peci_cputemp *priv)
> +{
> +	struct peci_get_temp_msg msg;
> +	int rc;
> +
> +	if (!peci_hwmon_need_update(&priv->temp.die))
> +		return 0;
> +
> +	msg.addr = priv->addr;
> +
> +	rc = peci_command(priv->client->adapter, PECI_CMD_GET_TEMP, &msg);
> +	if (rc)
> +		return rc;
> +
> +	/* Note that the tjmax should be available before calling it */
> +	priv->temp.die.value = priv->temp.tjmax.value +
> +			       (msg.temp_raw * 1000 / 64);
> +
> +	peci_hwmon_mark_updated(&priv->temp.die);
> +
> +	return 0;
> +}
> +
> +static int get_core_temp(struct peci_cputemp *priv, int core_index)
> +{
> +	s32 core_dts_margin;
> +	u8  pkg_cfg[4];
> +	int rc;
> +
> +	if (!peci_hwmon_need_update(&priv->temp.core[core_index]))
> +		return 0;
> +
> +	rc = peci_hwmon_rd_pkg_cfg_cmd(priv->client->adapter, priv->addr,
> +				       MBX_INDEX_PER_CORE_DTS_TEMP,
> +				       core_index, pkg_cfg);
> +	if (rc)
> +		return rc;
> +
> +	core_dts_margin = le16_to_cpup((__le16 *)pkg_cfg);
> +
> +	/**
> +	 * Processors return a value of the core DTS reading in 10.6 format
> +	 * (10 bits signed decimal, 6 bits fractional).
> +	 * Error codes:
> +	 *   0x8000: General sensor error
> +	 *   0x8001: Reserved
> +	 *   0x8002: Underflow on reading value
> +	 *   0x8003-0x81ff: Reserved
> +	 */
> +	if (core_dts_margin >= 0x8000 && core_dts_margin <= 0x81ff)
> +		return -EIO;
> +
> +	core_dts_margin = ten_dot_six_to_millidegree(core_dts_margin);
> +
> +	/* Note that the tjmax should be available before calling it */
> +	priv->temp.core[core_index].value = priv->temp.tjmax.value +
> +					    core_dts_margin;
> +
> +	peci_hwmon_mark_updated(&priv->temp.core[core_index]);
> +
> +	return 0;
> +}
> +
> +static int cputemp_read_string(struct device *dev,
> +			       enum hwmon_sensor_types type,
> +			       u32 attr, int channel, const char **str)
> +{
> +	if (attr != hwmon_temp_label)
> +		return -EOPNOTSUPP;
> +
> +	*str = cputemp_label[channel];
> +	return 0;
> +}
> +
> +static int cputemp_read(struct device *dev,
> +			enum hwmon_sensor_types type,
> +			u32 attr, int channel, long *val)
> +{
> +	struct peci_cputemp *priv = dev_get_drvdata(dev);
> +	int rc, core_index;
> +
> +	if (channel >= CPUTEMP_CHANNEL_NUMS ||
> +	    !(priv->temp_config[channel] & BIT(attr)))
> +		return -EOPNOTSUPP;
> +
> +	rc = get_temp_targets(priv);
> +	if (rc)
> +		return rc;
> +
> +	switch (attr) {
> +	case hwmon_temp_input:
> +		switch (channel) {
> +		case channel_die:
> +			rc = get_die_temp(priv);
> +			if (rc)
> +				break;
> +
> +			*val = priv->temp.die.value;
> +			break;
> +		case channel_tcontrol:
> +			*val = priv->temp.tcontrol.value;
> +			break;
> +		case channel_tthrottle:
> +			*val = priv->temp.tthrottle.value;
> +			break;
> +		case channel_tjmax:
> +			*val = priv->temp.tjmax.value;
> +			break;
> +		default:
> +			core_index = channel - DEFAULT_CHANNEL_NUMS;
> +			rc = get_core_temp(priv, core_index);
> +			if (rc)
> +				break;
> +
> +			*val = priv->temp.core[core_index].value;
> +			break;
> +		}
> +		break;
> +	case hwmon_temp_max:
> +		*val = priv->temp.tcontrol.value;
> +		break;
> +	case hwmon_temp_crit:
> +		*val = priv->temp.tjmax.value;
> +		break;
> +	case hwmon_temp_crit_hyst:
> +		*val = priv->temp.tjmax.value - priv->temp.tcontrol.value;
> +		break;
> +	default:
> +		rc = -EOPNOTSUPP;
> +		break;
> +	}
> +
> +	return rc;
> +}
> +
> +static umode_t cputemp_is_visible(const void *data,
> +				  enum hwmon_sensor_types type,
> +				  u32 attr, int channel)
> +{
> +	const struct peci_cputemp *priv = data;
> +
> +	if (priv->temp_config[channel] & BIT(attr))
> +		if (channel < DEFAULT_CHANNEL_NUMS ||
> +		    (channel >= DEFAULT_CHANNEL_NUMS &&
> +		     (priv->core_mask & BIT(channel - DEFAULT_CHANNEL_NUMS))))
> +			return 0444;
> +
> +	return 0;
> +}
> +
> +static const struct hwmon_ops cputemp_ops = {
> +	.is_visible = cputemp_is_visible,
> +	.read_string = cputemp_read_string,
> +	.read = cputemp_read,
> +};
> +
> +static int check_resolved_cores(struct peci_cputemp *priv)
> +{
> +	struct peci_rd_pci_cfg_local_msg msg;
> +	int rc;
> +
> +	/* Get the RESOLVED_CORES register value */
> +	msg.addr = priv->addr;
> +	msg.bus = REG_RESOLVED_CORES_BUS;
> +	msg.device = REG_RESOLVED_CORES_DEVICE;
> +	msg.function = REG_RESOLVED_CORES_FUNCTION;
> +	msg.reg = REG_RESOLVED_CORES_OFFSET;
> +	msg.rx_len = 4;
> +
> +	rc = peci_command(priv->client->adapter, PECI_CMD_RD_PCI_CFG_LOCAL,
> +			  &msg);
> +	if (rc)
> +		return rc;
> +
> +	priv->core_mask = le32_to_cpup((__le32 *)msg.pci_config);
> +	if (!priv->core_mask)
> +		return -EAGAIN;
> +
> +	dev_dbg(priv->dev, "Scanned resolved cores: 0x%x\n", priv->core_mask);
> +	return 0;
> +}
> +
> +static int create_core_temp_info(struct peci_cputemp *priv)
> +{
> +	int rc, i;
> +
> +	rc = check_resolved_cores(priv);
> +	if (rc)
> +		return rc;
> +
> +	for (i = 0; i < priv->gen_info->core_max; i++)
> +		if (priv->core_mask & BIT(i))
> +			while (i + DEFAULT_CHANNEL_NUMS >= priv->config_idx)
> +				priv->temp_config[priv->config_idx++] =
> +					config_table[channel_core];
> +
> +	return 0;
> +}
> +
> +static int peci_cputemp_probe(struct peci_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct peci_cputemp *priv;
> +	struct device *hwmon_dev;
> +	int rc;
> +
> +	if ((client->adapter->cmd_mask &
> +	    (BIT(PECI_CMD_GET_TEMP) | BIT(PECI_CMD_RD_PKG_CFG))) !=
> +	    (BIT(PECI_CMD_GET_TEMP) | BIT(PECI_CMD_RD_PKG_CFG)))
> +		return -ENODEV;
> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	dev_set_drvdata(dev, priv);
> +	priv->client = client;
> +	priv->dev = dev;
> +	priv->addr = client->addr;
> +	priv->cpu_no = priv->addr - PECI_BASE_ADDR;
> +
> +	snprintf(priv->name, PECI_NAME_SIZE, "peci_cputemp.cpu%d",
> +		 priv->cpu_no);
> +
> +	rc = peci_hwmon_get_cpu_gen_info(client->adapter, priv->addr,
> +					 &priv->gen_info);
> +	if (rc)
> +		return rc;
> +
> +	priv->temp_config[priv->config_idx++] = config_table[channel_die];
> +	priv->temp_config[priv->config_idx++] = config_table[channel_tcontrol];
> +	priv->temp_config[priv->config_idx++] = config_table[channel_tthrottle];
> +	priv->temp_config[priv->config_idx++] = config_table[channel_tjmax];
> +
> +	rc = create_core_temp_info(priv);
> +	if (rc)
> +		dev_dbg(dev, "Skipped creating core temp info\n");
> +
> +	priv->chip.ops = &cputemp_ops;
> +	priv->chip.info = priv->info;
> +
> +	priv->info[0] = &priv->temp_info;
> +
> +	priv->temp_info.type = hwmon_temp;
> +	priv->temp_info.config = priv->temp_config;
> +
> +	hwmon_dev = devm_hwmon_device_register_with_info(priv->dev,
> +							 priv->name,
> +							 priv,
> +							 &priv->chip,
> +							 NULL);
> +
> +	if (IS_ERR(hwmon_dev))
> +		return PTR_ERR(hwmon_dev);
> +
> +	dev_dbg(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), priv->name);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id peci_cputemp_of_table[] = {
> +	{ .compatible = "intel,peci-cputemp" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, peci_cputemp_of_table);
> +
> +static const struct peci_device_id peci_cputemp_ids[] = {
> +	{ "peci-cputemp", 0, },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(peci, peci_cputemp_ids);
> +
> +static struct peci_driver peci_cputemp_driver = {
> +	.probe    = peci_cputemp_probe,
> +	.id_table = peci_cputemp_ids,
> +	.driver   = {
> +			.name           = "peci-cputemp",
> +			.of_match_table = of_match_ptr(peci_cputemp_of_table),
> +	},
> +};
> +module_peci_driver(peci_cputemp_driver);
> +
> +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("PECI cputemp driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/hwmon/peci-hwmon.c b/drivers/hwmon/peci-hwmon.c
> new file mode 100644
> index 000000000000..e137e301eb97
> --- /dev/null
> +++ b/drivers/hwmon/peci-hwmon.c
> @@ -0,0 +1,124 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2018 Intel Corporation
> +
> +#include <linux/bitfield.h>
> +#include <linux/module.h>
> +#include <linux/peci.h>
> +
> +#include "peci-hwmon.h"
> +
> +#if IS_ENABLED(CONFIG_X86)
> +#include <asm/intel-family.h>
> +#else
> +#define INTEL_FAM6_HASWELL_X   0x3F
> +#define INTEL_FAM6_BROADWELL_X 0x4F
> +#define INTEL_FAM6_SKYLAKE_X   0x55
> +#endif

The entire code is very Intel specific. Why this #if instead of
making the driver dependent on X86 ?

> +
> +#define LOWER_NIBBLE_MASK      GENMASK(3, 0)
> +#define UPPER_NIBBLE_MASK      GENMASK(7, 4)
> +
> +#define CPU_ID_MODEL_MASK      GENMASK(7, 4)
> +#define CPU_ID_FAMILY_MASK     GENMASK(11, 8)
> +#define CPU_ID_EXT_MODEL_MASK  GENMASK(19, 16)
> +#define CPU_ID_EXT_FAMILY_MASK GENMASK(27, 20)
> +
> +enum cpu_gens {
> +	CPU_GEN_HSX = 0, /* Haswell Xeon */
> +	CPU_GEN_BRX,     /* Broadwell Xeon */
> +	CPU_GEN_SKX,     /* Skylake Xeon */
> +};
> +
> +static const struct cpu_gen_info cpu_gen_info_table[] = {
> +	[CPU_GEN_HSX] = {
> +		.family        = 6, /* Family code */
> +		.model         = INTEL_FAM6_HASWELL_X,
> +		.core_max      = CORE_MAX_ON_HSX,
> +		.chan_rank_max = CHAN_RANK_MAX_ON_HSX,
> +		.dimm_idx_max  = DIMM_IDX_MAX_ON_HSX },
> +	[CPU_GEN_BRX] = {
> +		.family        = 6, /* Family code */
> +		.model         = INTEL_FAM6_BROADWELL_X,
> +		.core_max      = CORE_MAX_ON_BDX,
> +		.chan_rank_max = CHAN_RANK_MAX_ON_BDX,
> +		.dimm_idx_max  = DIMM_IDX_MAX_ON_BDX },
> +	[CPU_GEN_SKX] = {
> +		.family        = 6, /* Family code */
> +		.model         = INTEL_FAM6_SKYLAKE_X,
> +		.core_max      = CORE_MAX_ON_SKX,
> +		.chan_rank_max = CHAN_RANK_MAX_ON_SKX,
> +		.dimm_idx_max  = DIMM_IDX_MAX_ON_SKX },
> +};
> +
> +int peci_hwmon_get_cpu_gen_info(struct peci_adapter *adapter, u8 addr,
> +				const struct cpu_gen_info **gen_info)
> +{
> +	u32 cpu_id;
> +	int i, rc;
> +
> +	rc = peci_get_cpu_id(adapter, addr, &cpu_id);
> +	if (rc)
> +		return rc;
> +
> +	for (i = 0; i < ARRAY_SIZE(cpu_gen_info_table); i++) {
> +		if (FIELD_GET(CPU_ID_FAMILY_MASK, cpu_id) +
> +			FIELD_GET(CPU_ID_EXT_FAMILY_MASK, cpu_id) ==
> +				cpu_gen_info_table[i].family &&
> +		    FIELD_GET(CPU_ID_MODEL_MASK, cpu_id) ==
> +			FIELD_GET(LOWER_NIBBLE_MASK,
> +				  cpu_gen_info_table[i].model) &&
> +		    FIELD_GET(CPU_ID_EXT_MODEL_MASK, cpu_id) ==
> +			FIELD_GET(UPPER_NIBBLE_MASK,
> +				  cpu_gen_info_table[i].model)) {
> +			break;
> +		}
> +	}
> +
> +	if (i >= ARRAY_SIZE(cpu_gen_info_table))
> +		return -ENODEV;
> +
> +	*gen_info = &cpu_gen_info_table[i];
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(peci_hwmon_get_cpu_gen_info);
> +
> +bool peci_hwmon_need_update(struct temp_data *temp)
> +{
> +	if (temp->valid &&
> +	    time_before(jiffies, temp->last_updated + UPDATE_INTERVAL))
> +		return false;
> +
> +	return true;
> +}
> +EXPORT_SYMBOL_GPL(peci_hwmon_need_update);
> +
> +void peci_hwmon_mark_updated(struct temp_data *temp)
> +{
> +	temp->valid = 1;
> +	temp->last_updated = jiffies;
> +}
> +EXPORT_SYMBOL_GPL(peci_hwmon_mark_updated);
> +
> +int peci_hwmon_rd_pkg_cfg_cmd(struct peci_adapter *adapter, u8 addr,
> +			      u8 mbx_idx, u16 param, u8 *data)
> +{
> +	struct peci_rd_pkg_cfg_msg msg;
> +	int rc;
> +
> +	msg.addr = addr;
> +	msg.index = mbx_idx;
> +	msg.param = param;
> +	msg.rx_len = 4;
> +
> +	rc = peci_command(adapter, PECI_CMD_RD_PKG_CFG, &msg);
> +	if (!rc)
> +		memcpy(data, msg.pkg_config, 4);
> +
> +	return rc;
> +}
> +EXPORT_SYMBOL_GPL(peci_hwmon_rd_pkg_cfg_cmd);
> +
> +MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("PECI hwmon module");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/hwmon/peci-hwmon.h b/drivers/hwmon/peci-hwmon.h
> new file mode 100644
> index 000000000000..0896c27f33d8
> --- /dev/null
> +++ b/drivers/hwmon/peci-hwmon.h
> @@ -0,0 +1,51 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (c) 2018 Intel Corporation */
> +
> +#ifndef __PECI_HWMON_H
> +#define __PECI_HWMON_H
> +
> +#include <linux/peci.h>
> +
> +#define TEMP_TYPE_PECI         6 /* Sensor type 6: Intel PECI */
> +
> +#define UPDATE_INTERVAL        HZ
> +
> +struct temp_data {
> +	uint  valid;
> +	s32   value;
> +	ulong last_updated;
> +};
> +
> +struct cpu_gen_info {
> +	u16  family;
> +	u8   model;
> +	uint core_max;
> +	uint chan_rank_max;
> +	uint dimm_idx_max;
> +};
> +
> +#define CORE_MAX_ON_HSX        18 /* Max number of cores on Haswell */
> +#define CHAN_RANK_MAX_ON_HSX   8  /* Max number of channel ranks on Haswell */
> +#define DIMM_IDX_MAX_ON_HSX    3  /* Max DIMM index per channel on Haswell */
> +
> +#define CORE_MAX_ON_BDX        24 /* Max number of cores on Broadwell */
> +#define CHAN_RANK_MAX_ON_BDX   4  /* Max number of channel ranks on Broadwell */
> +#define DIMM_IDX_MAX_ON_BDX    3  /* Max DIMM index per channel on Broadwell */
> +
> +#define CORE_MAX_ON_SKX        28 /* Max number of cores on Skylake */
> +#define CHAN_RANK_MAX_ON_SKX   6  /* Max number of channel ranks on Skylake */
> +#define DIMM_IDX_MAX_ON_SKX    2  /* Max DIMM index per channel on Skylake */
> +
> +#define CORE_NUMS_MAX          CORE_MAX_ON_SKX
> +#define CHAN_RANK_MAX          CHAN_RANK_MAX_ON_HSX
> +#define DIMM_IDX_MAX           DIMM_IDX_MAX_ON_HSX
> +#define DIMM_NUMS_MAX          (CHAN_RANK_MAX * DIMM_IDX_MAX)
> +
> +int  peci_hwmon_get_cpu_gen_info(struct peci_adapter *adapter, u8 addr,
> +				 const struct cpu_gen_info **gen_info);
> +bool peci_hwmon_need_update(struct temp_data *temp);
> +void peci_hwmon_mark_updated(struct temp_data *temp);
> +int  peci_hwmon_rd_pkg_cfg_cmd(struct peci_adapter *adapter, u8 addr,
> +			       u8 mbx_idx, u16 param, u8 *data);
> +
> +#endif /* __PECI_HWMON_H */
> -- 
> 2.17.0
>