Re: [PATCH v3 3/4] hwmon: smpro: Add Ampere's Altra smpro-hwmon driver

Guenter Roeck
2021-04-14T12:33:56Z

On Fri, Apr 09, 2021 at 10:13:31AM +0700, Quan Nguyen wrote:
> This commit adds support for Ampere SMpro hwmon driver. This driver
> supports accessing various CPU sensors provided by the SMpro co-processor
> including temperature, power, voltages, and current.
>
> Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
> ---

Change log goes here. You are making it difficult to review your patches.

> drivers/hwmon/Kconfig | 8 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/smpro-hwmon.c | 491 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 500 insertions(+)
> create mode 100644 drivers/hwmon/smpro-hwmon.c
>
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 0ddc974b102e..ba4b5a911baf 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -67,6 +67,14 @@ config SENSORS_ABITUGURU3
> This driver can also be built as a module. If so, the module
> will be called abituguru3.
>
> +config SENSORS_SMPRO
> + tristate "Ampere's Altra SMpro hardware monitoring driver"
> + depends on MFD_SMPRO
> + help
> + If you say yes here you get support for the thermal, voltage,
> + current and power sensors of Ampere's Altra processor family SoC
> + with SMpro co-processor.
> +
> config SENSORS_AD7314
> tristate "Analog Devices AD7314 and compatibles"
> depends on SPI
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 59e78bc212cf..b25391f9c651 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -174,6 +174,7 @@ obj-$(CONFIG_SENSORS_SHT3x) += sht3x.o
> obj-$(CONFIG_SENSORS_SHTC1) += shtc1.o
> obj-$(CONFIG_SENSORS_SIS5595) += sis5595.o
> obj-$(CONFIG_SENSORS_SMM665) += smm665.o
> +obj-$(CONFIG_SENSORS_SMPRO) += smpro-hwmon.o
> obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
> obj-$(CONFIG_SENSORS_SMSC47M1) += smsc47m1.o
> obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
> diff --git a/drivers/hwmon/smpro-hwmon.c b/drivers/hwmon/smpro-hwmon.c
> new file mode 100644
> index 000000000000..a3389fcbad82
> --- /dev/null
> +++ b/drivers/hwmon/smpro-hwmon.c
> @@ -0,0 +1,491 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Ampere Computing SoC's SMPro Hardware Monitoring Driver
> + *
> + * Copyright (c) 2021, Ampere Computing LLC
> + */
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/kernel.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +
> +/* Identification Registers */
> +#define MANUFACTURER_ID_REG 0x02
> +#define AMPERE_MANUFACTURER_ID 0xCD3A
> +
> +/* Logical Power Sensor Registers */
> +#define SOC_TEMP 0x00
> +#define SOC_VRD_TEMP 0x01
> +#define DIMM_VRD_TEMP 0x02
> +#define CORE_VRD_TEMP 0x03
> +#define CH0_DIMM_TEMP 0x04
> +#define CH1_DIMM_TEMP 0x05
> +#define CH2_DIMM_TEMP 0x06
> +#define CH3_DIMM_TEMP 0x07
> +#define CH4_DIMM_TEMP 0x08
> +#define CH5_DIMM_TEMP 0x09
> +#define CH6_DIMM_TEMP 0x0A
> +#define CH7_DIMM_TEMP 0x0B
> +#define RCA_VRD_TEMP 0x0C
> +
> +#define CORE_VRD_PWR 0x10
> +#define SOC_PWR 0x11
> +#define DIMM_VRD1_PWR 0x12
> +#define DIMM_VRD2_PWR 0x13
> +#define CORE_VRD_PWR_MW 0x16
> +#define SOC_PWR_MW 0x17
> +#define DIMM_VRD1_PWR_MW 0x18
> +#define DIMM_VRD2_PWR_MW 0x19
> +#define RCA_VRD_PWR 0x1A
> +#define RCA_VRD_PWR_MW 0x1B
> +
> +#define MEM_HOT_THRESHOLD 0x22
> +#define SOC_VR_HOT_THRESHOLD 0x23
> +#define CORE_VRD_VOLT 0x24
> +#define SOC_VRD_VOLT 0x25
> +#define DIMM_VRD1_VOLT 0x26
> +#define DIMM_VRD2_VOLT 0x27
> +#define RCA_VRD_VOLT 0x28
> +
> +#define CORE_VRD_CURR 0x29
> +#define SOC_VRD_CURR 0x2A
> +#define DIMM_VRD1_CURR 0x2B
> +#define DIMM_VRD2_CURR 0x2C
> +#define RCA_VRD_CURR 0x2D
> +
> +struct smpro_hwmon {
> + struct regmap *regmap;
> + u32 offset;
> +};
> +
> +struct smpro_sensor {
> + const u8 reg;
> + const u8 reg_ext;
> + const char *label;
> +};
> +
> +static const struct smpro_sensor temperature[] = {
> + {
> + .reg = SOC_TEMP,
> + .label = "temp1 SoC"
> + },
> + {
> + .reg = SOC_VRD_TEMP,
> + .reg_ext = SOC_VR_HOT_THRESHOLD,
> + .label = "temp2 SoC VRD"
> + },
> + {
> + .reg = DIMM_VRD_TEMP,
> + .label = "temp3 DIMM VRD"
> + },
> + {
> + .reg = CORE_VRD_TEMP,
> + .label = "temp4 CORE VRD"
> + },
> + {
> + .reg = CH0_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp5 CH0 DIMM"
> + },
> + {
> + .reg = CH1_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp6 CH1 DIMM"
> + },
> + {
> + .reg = CH2_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp7 CH2 DIMM"
> + },
> + {
> + .reg = CH3_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp8 CH3 DIMM"
> + },
> + {
> + .reg = CH4_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp9 CH4 DIMM"
> + },
> + {
> + .reg = CH5_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp10 CH5 DIMM"
> + },
> + {
> + .reg = CH6_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp11 CH6 DIMM"
> + },
> + {
> + .reg = CH7_DIMM_TEMP,
> + .reg_ext = MEM_HOT_THRESHOLD,
> + .label = "temp12 CH7 DIMM"
> + },
> + {
> + .reg = RCA_VRD_TEMP,
> + .label = "temp13 RCA VRD"
> + },
> +};
> +
> +static const struct smpro_sensor voltage[] = {
> + {
> + .reg = CORE_VRD_VOLT,
> + .label = "vout0 CORE VRD"
> + },
> + {
> + .reg = SOC_VRD_VOLT,
> + .label = "vout1 SoC VRD"
> + },
> + {
> + .reg = DIMM_VRD1_VOLT,
> + .label = "vout2 DIMM VRD1"
> + },
> + {
> + .reg = DIMM_VRD2_VOLT,
> + .label = "vout3 DIMM VRD2"
> + },
> + {
> + .reg = RCA_VRD_VOLT,
> + .label = "vout4 RCA VRD"
> + },
> +};
> +
> +static const struct smpro_sensor curr_sensor[] = {
> + {
> + .reg = CORE_VRD_CURR,
> + .label = "iout1 CORE VRD"
> + },
> + {
> + .reg = SOC_VRD_CURR,
> + .label = "iout2 SoC VRD"
> + },
> + {
> + .reg = DIMM_VRD1_CURR,
> + .label = "iout3 DIMM VRD1"
> + },
> + {
> + .reg = DIMM_VRD2_CURR,
> + .label = "iout4 DIMM VRD2"
> + },
> + {
> + .reg = RCA_VRD_CURR,
> + .label = "iout5 RCA VRD"
> + },
> +};
> +
> +static const struct smpro_sensor power[] = {
> + {
> + .reg = CORE_VRD_PWR,
> + .reg_ext = CORE_VRD_PWR_MW,
> + .label = "power1 CORE VRD"
> + },
> + {
> + .reg = SOC_PWR,
> + .reg_ext = SOC_PWR_MW,
> + .label = "power2 SoC"
> + },
> + {
> + .reg = DIMM_VRD1_PWR,
> + .reg_ext = DIMM_VRD1_PWR_MW,
> + .label = "power3 DIMM VRD1"
> + },
> + {
> + .reg = DIMM_VRD2_PWR,
> + .reg_ext = DIMM_VRD2_PWR_MW,
> + .label = "power4 DIMM VRD2"
> + },
> + {
> + .reg = RCA_VRD_PWR,
> + .reg_ext = RCA_VRD_PWR_MW,
> + .label = "power5 RCA VRD"
> + },
> +};
> +
> +static int smpro_read_temp(struct device *dev, u32 attr, int channel, long *val)
> +{
> + struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> + unsigned int value;
> + int ret;
> +
> + switch (attr) {
> + case hwmon_temp_input:
> + ret = regmap_read(hwmon->regmap, hwmon->offset + temperature[channel].reg, &value);
> + if (ret)
> + return ret;
> + break;
> + case hwmon_temp_crit:
> + ret = regmap_read(hwmon->regmap,
> + hwmon->offset + temperature[channel].reg_ext, &value);
> + if (ret)
> + return ret;
> + break;
> + default:
> + return -EOPNOTSUPP;
> + }
> +
> + *val = sign_extend32(value, 8) * 1000;
> + return 0;
> +}
> +
> +static int smpro_read_in(struct device *dev, u32 attr, int channel, long *val)
> +{
> + struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> + unsigned int value;
> + int ret;
> +
> + switch (attr) {
> + case hwmon_in_input:
> + ret = regmap_read(hwmon->regmap, hwmon->offset + voltage[channel].reg, &value);
> + if (ret < 0)
> + return ret;
> + /* 15-bit value in 1mV */
> + *val = value & 0x7fff;
> + return 0;
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> +static int smpro_read_curr(struct device *dev, u32 attr, int channel, long *val)
> +{
> + struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> + unsigned int value;
> + int ret;
> +
> + switch (attr) {
> + case hwmon_curr_input:
> + ret = regmap_read(hwmon->regmap, hwmon->offset + curr_sensor[channel].reg, &value);
> + if (ret < 0)
> + return ret;
> + /* Scale reported by the hardware is 1mA */
> + *val = value & 0x7fff;
> + return 0;
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> +static int smpro_read_power(struct device *dev, u32 attr, int channel, long *val_pwr)
> +{
> + struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> + unsigned int val = 0, val_mw = 0;
> + int ret;
> +
> + switch (attr) {
> + case hwmon_power_input:
> + ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg, &val);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg_ext, &val_mw);
> + if (ret)
> + return ret;
> +
> + *val_pwr = val * 1000000 + val_mw * 1000;
> + return 0;
> +
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> +static int smpro_read(struct device *dev, enum hwmon_sensor_types type,
> + u32 attr, int channel, long *val)
> +{
> + switch (type) {
> + case hwmon_temp:
> + return smpro_read_temp(dev, attr, channel, val);
> + case hwmon_in:
> + return smpro_read_in(dev, attr, channel, val);
> + case hwmon_power:
> + return smpro_read_power(dev, attr, channel, val);
> + case hwmon_curr:
> + return smpro_read_curr(dev, attr, channel, val);
> + default:
> + return -EOPNOTSUPP;
> + }
> +}
> +
> +static int smpro_read_string(struct device *dev, enum hwmon_sensor_types type,
> + u32 attr, int channel, const char **str)
> +{
> + switch (type) {
> + case hwmon_temp:
> + switch (attr) {
> + case hwmon_temp_label:
> + *str = temperature[channel].label;
> + return 0;
> + default:
> + break;
> + }
> + break;
> +
> + case hwmon_in:
> + switch (attr) {
> + case hwmon_in_label:
> + *str = voltage[channel].label;
> + return 0;
> + default:
> + break;
> + }
> + break;
> +
> + case hwmon_curr:
> + switch (attr) {
> + case hwmon_curr_label:
> + *str = curr_sensor[channel].label;
> + return 0;
> + default:
> + break;
> + }
> + break;
> +
> + case hwmon_power:
> + switch (attr) {
> + case hwmon_power_label:
> + *str = power[channel].label;
> + return 0;
> + default:
> + break;
> + }
> + break;
> + default:
> + break;
> + }
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static umode_t smpro_is_visible(const void *data, enum hwmon_sensor_types type,
> + u32 attr, int channel)
> +{
> + const struct smpro_hwmon *hwmon = data;
> + unsigned int value;
> + int ret;
> +
> + switch (type) {
> + case hwmon_temp:
> + switch (attr) {
> + case hwmon_temp_input:
> + case hwmon_temp_label:
> + case hwmon_temp_crit:
> + ret = regmap_read(hwmon->regmap,
> + hwmon->offset + temperature[channel].reg, &value);
> + if (ret || value == 0xFFFF)
> + return 0;
> + break;
> + }
> + default:
> + break;
> + }
> +
> + return 0444;
> +}
> +
> +static const struct hwmon_channel_info *smpro_info[] = {
> + HWMON_CHANNEL_INFO(temp,
> + HWMON_T_INPUT | HWMON_T_LABEL,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL,
> + HWMON_T_INPUT | HWMON_T_LABEL,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> + HWMON_T_INPUT | HWMON_T_LABEL),
> + HWMON_CHANNEL_INFO(in,
> + HWMON_I_INPUT | HWMON_I_LABEL,
> + HWMON_I_INPUT | HWMON_I_LABEL,
> + HWMON_I_INPUT | HWMON_I_LABEL,
> + HWMON_I_INPUT | HWMON_I_LABEL,
> + HWMON_I_INPUT | HWMON_I_LABEL),
> + HWMON_CHANNEL_INFO(power,
> + HWMON_P_INPUT | HWMON_P_LABEL,
> + HWMON_P_INPUT | HWMON_P_LABEL,
> + HWMON_P_INPUT | HWMON_P_LABEL,
> + HWMON_P_INPUT | HWMON_P_LABEL,
> + HWMON_P_INPUT | HWMON_P_LABEL),
> + HWMON_CHANNEL_INFO(curr,
> + HWMON_C_INPUT | HWMON_C_LABEL,
> + HWMON_C_INPUT | HWMON_C_LABEL,
> + HWMON_C_INPUT | HWMON_C_LABEL,
> + HWMON_C_INPUT | HWMON_C_LABEL,
> + HWMON_C_INPUT | HWMON_C_LABEL),
> + NULL
> +};
> +
> +static const struct hwmon_ops smpro_hwmon_ops = {
> + .is_visible = smpro_is_visible,
> + .read = smpro_read,
> + .read_string = smpro_read_string,
> +};
> +
> +static const struct hwmon_chip_info smpro_chip_info = {
> + .ops = &smpro_hwmon_ops,
> + .info = smpro_info,
> +};
> +
> +static int smpro_hwmon_probe(struct platform_device *pdev)
> +{
> + struct smpro_hwmon *hwmon;
> + struct device *hwmon_dev;
> + unsigned int val;
> + int ret;
> +
> + hwmon = devm_kzalloc(&pdev->dev, sizeof(struct smpro_hwmon), GFP_KERNEL);
> + if (!hwmon)
> + return -ENOMEM;
> +
> + hwmon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> + if (!hwmon->regmap)
> + return -ENODEV;
> +
> + ret = device_property_read_u32(&pdev->dev, "reg", &hwmon->offset);
> + if (ret)
> + return -EINVAL;
> +
> + /* Check for valid ID */
> + ret = regmap_read(hwmon->regmap, MANUFACTURER_ID_REG, &val);
> + if (ret)
> + return -EPROBE_DEFER;

This is unacceptable. regmap_read() could return various errors.
An error here might mean that the chip is simply not there, or that
there is some other problem with, say, the i2c controller driver.
The function might, for all we know, even return -ENOMEM.

If this is supposed to mean that the chip is not yet ready, some other
and more specific solution will be needed. -EPROBE_DEFER means that
some other driver needs to be loaded first, not "chip is not ready,
try again later".

Thanks,
Guenter

> +
> + if (val != AMPERE_MANUFACTURER_ID)
> + return -ENODEV;
> +
> + hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, "smpro_hwmon",
> + hwmon, &smpro_chip_info, NULL);
> +
> + return PTR_ERR_OR_ZERO(hwmon_dev);
> +}
> +
> +static const struct of_device_id smpro_hwmon_of_match[] = {
> + { .compatible = "ampere,ac01-hwmon" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, smpro_hwmon_of_match);
> +
> +static struct platform_driver smpro_hwmon_driver = {
> + .probe = smpro_hwmon_probe,
> + .driver = {
> + .name = "smpro-hwmon",
> + .of_match_table = smpro_hwmon_of_match,
> + },
> +};
> +
> +module_platform_driver(smpro_hwmon_driver);
> +
> +MODULE_AUTHOR("Thu Nguyen <thu@os.amperecomputing.com>");
> +MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
> +MODULE_DESCRIPTION("Ampere Altra SMPro hwmon driver");
> +MODULE_LICENSE("GPL v2");