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

Quan Nguyen
2021-04-15T04:13:46Z

On 14/04/2021 19:33, Guenter Roeck wrote:
> 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.
>
Will add changelog here in next version.

>> 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
>

Thanks to this clarification and will return regmap_read() return value,
ie: "return ret" in next version.

>> +
>> + 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");