This patch adds support to thermal management private feature for DFL FPGA Management Engine (FME). This private feature driver registers a hwmon for thermal/temperature monitoring (hwmon temp1_input). If hardware automatic throttling is supported by this hardware, then driver also exposes sysfs interfaces under hwmon for thresholds (temp1_max/ crit/ emergency), threshold alarms (temp1_max_alarm/ temp1_crit_alarm) and throttling policy (temp1_max_policy). Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx> Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx> Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx> Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx> Acked-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- v2: create a dfl_fme_thermal hwmon to expose thermal information. move all sysfs interfaces under hwmon tempareture --> hwmon temp1_input threshold1 --> hwmon temp1_alarm threshold2 --> hwmon temp1_crit trip_threshold --> hwmon temp1_emergency threshold1_status --> hwmon temp1_alarm_status threshold2_status --> hwmon temp1_crit_status threshold1_policy --> hwmon temp1_alarm_policy v3: rename some hwmon sysfs interfaces to follow hwmon ABI. temp1_alarm --> temp1_max temp1_alarm_status --> temp1_max_alarm temp1_crit_status --> temp1_crit_alarm temp1_alarm_policy --> temp1_max_policy update sysfs doc for above sysfs interface changes. replace scnprintf with sprintf in sysfs interface. v4: use HWMON_CHANNEL_INFO. rebase, and update date in sysfs doc. v5: no change. --- Documentation/ABI/testing/sysfs-platform-dfl-fme | 64 ++++++++ drivers/fpga/Kconfig | 2 +- drivers/fpga/dfl-fme-main.c | 187 +++++++++++++++++++++++ 3 files changed, 252 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-platform-dfl-fme b/Documentation/ABI/testing/sysfs-platform-dfl-fme index 86eef83..2cd17dc 100644 --- a/Documentation/ABI/testing/sysfs-platform-dfl-fme +++ b/Documentation/ABI/testing/sysfs-platform-dfl-fme @@ -119,3 +119,67 @@ Description: Write-only. Write error code to this file to clear all errors logged in errors, first_error and next_error. Write fails with -EINVAL if input parsing fails or input error code doesn't match. + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/name +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-Only. Read this file to get the name of hwmon device, it + supports values: + 'dfl_fme_thermal' - thermal hwmon device name + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_input +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-Only. It returns FPGA device temperature in millidegrees + Celsius. + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_max +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-Only. It returns hardware threshold1 temperature in + millidegrees Celsius. If temperature rises at or above this + threshold, hardware starts 50% or 90% throttling (see + 'temp1_max_policy'). + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_crit +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-Only. It returns hardware threshold2 temperature in + millidegrees Celsius. If temperature rises at or above this + threshold, hardware starts 100% throttling. + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_emergency +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-Only. It returns hardware trip threshold temperature in + millidegrees Celsius. If temperature rises at or above this + threshold, a fatal event will be triggered to board management + controller (BMC) to shutdown FPGA. + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_max_alarm +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-only. It returns 1 if temperature is currently at or above + hardware threshold1 (see 'temp1_max'), otherwise 0. + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_crit_alarm +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-only. It returns 1 if temperature is currently at or above + hardware threshold2 (see 'temp1_crit'), otherwise 0. + +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_max_policy +Date: June 2019 +KernelVersion: 5.3 +Contact: Wu Hao <hao.wu@xxxxxxxxx> +Description: Read-Only. Read this file to get the policy of hardware threshold1 + (see 'temp1_max'). It only supports two values (policies): + 0 - AP2 state (90% throttling) + 1 - AP1 state (50% throttling) diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig index 8072c19..48f6224 100644 --- a/drivers/fpga/Kconfig +++ b/drivers/fpga/Kconfig @@ -155,7 +155,7 @@ config FPGA_DFL config FPGA_DFL_FME tristate "FPGA DFL FME Driver" - depends on FPGA_DFL + depends on FPGA_DFL && HWMON help The FPGA Management Engine (FME) is a feature device implemented under Device Feature List (DFL) framework. Select this option to diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c index 4490cf4..59ff9f1 100644 --- a/drivers/fpga/dfl-fme-main.c +++ b/drivers/fpga/dfl-fme-main.c @@ -14,6 +14,8 @@ * Henry Mitchel <henry.mitchel@xxxxxxxxx> */ +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/uaccess.h> @@ -217,6 +219,187 @@ static long fme_hdr_ioctl(struct platform_device *pdev, .ioctl = fme_hdr_ioctl, }; +#define FME_THERM_THRESHOLD 0x8 +#define TEMP_THRESHOLD1 GENMASK_ULL(6, 0) +#define TEMP_THRESHOLD1_EN BIT_ULL(7) +#define TEMP_THRESHOLD2 GENMASK_ULL(14, 8) +#define TEMP_THRESHOLD2_EN BIT_ULL(15) +#define TRIP_THRESHOLD GENMASK_ULL(30, 24) +#define TEMP_THRESHOLD1_STATUS BIT_ULL(32) /* threshold1 reached */ +#define TEMP_THRESHOLD2_STATUS BIT_ULL(33) /* threshold2 reached */ +/* threshold1 policy: 0 - AP2 (90% throttle) / 1 - AP1 (50% throttle) */ +#define TEMP_THRESHOLD1_POLICY BIT_ULL(44) + +#define FME_THERM_RDSENSOR_FMT1 0x10 +#define FPGA_TEMPERATURE GENMASK_ULL(6, 0) + +#define FME_THERM_CAP 0x20 +#define THERM_NO_THROTTLE BIT_ULL(0) + +#define MD_PRE_DEG + +static bool fme_thermal_throttle_support(void __iomem *base) +{ + u64 v = readq(base + FME_THERM_CAP); + + return FIELD_GET(THERM_NO_THROTTLE, v) ? false : true; +} + +static umode_t thermal_hwmon_attrs_visible(const void *drvdata, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + const struct dfl_feature *feature = drvdata; + + /* temperature is always supported, and check hardware cap for others */ + if (attr == hwmon_temp_input) + return 0444; + + return fme_thermal_throttle_support(feature->ioaddr) ? 0444 : 0; +} + +static int thermal_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct dfl_feature *feature = dev_get_drvdata(dev); + u64 v; + + switch (attr) { + case hwmon_temp_input: + v = readq(feature->ioaddr + FME_THERM_RDSENSOR_FMT1); + *val = (long)(FIELD_GET(FPGA_TEMPERATURE, v) * 1000); + break; + case hwmon_temp_max: + v = readq(feature->ioaddr + FME_THERM_THRESHOLD); + *val = (long)(FIELD_GET(TEMP_THRESHOLD1, v) * 1000); + break; + case hwmon_temp_crit: + v = readq(feature->ioaddr + FME_THERM_THRESHOLD); + *val = (long)(FIELD_GET(TEMP_THRESHOLD2, v) * 1000); + break; + case hwmon_temp_emergency: + v = readq(feature->ioaddr + FME_THERM_THRESHOLD); + *val = (long)(FIELD_GET(TRIP_THRESHOLD, v) * 1000); + break; + case hwmon_temp_max_alarm: + v = readq(feature->ioaddr + FME_THERM_THRESHOLD); + *val = (long)FIELD_GET(TEMP_THRESHOLD1_STATUS, v); + break; + case hwmon_temp_crit_alarm: + v = readq(feature->ioaddr + FME_THERM_THRESHOLD); + *val = (long)FIELD_GET(TEMP_THRESHOLD2_STATUS, v); + break; + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static const struct hwmon_ops thermal_hwmon_ops = { + .is_visible = thermal_hwmon_attrs_visible, + .read = thermal_hwmon_read, +}; + +static const struct hwmon_channel_info *thermal_hwmon_info[] = { + HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_EMERGENCY | + HWMON_T_MAX | HWMON_T_MAX_ALARM | + HWMON_T_CRIT | HWMON_T_CRIT_ALARM), + NULL +}; + +static const struct hwmon_chip_info thermal_hwmon_chip_info = { + .ops = &thermal_hwmon_ops, + .info = thermal_hwmon_info, +}; + +static ssize_t temp1_max_policy_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dfl_feature *feature = dev_get_drvdata(dev); + u64 v; + + v = readq(feature->ioaddr + FME_THERM_THRESHOLD); + + return sprintf(buf, "%u\n", + (unsigned int)FIELD_GET(TEMP_THRESHOLD1_POLICY, v)); +} + +static DEVICE_ATTR_RO(temp1_max_policy); + +static struct attribute *thermal_extra_attrs[] = { + &dev_attr_temp1_max_policy.attr, + NULL, +}; + +static umode_t thermal_extra_attrs_visible(struct kobject *kobj, + struct attribute *attr, int index) +{ + struct device *dev = kobj_to_dev(kobj); + struct dfl_feature *feature = dev_get_drvdata(dev); + + return fme_thermal_throttle_support(feature->ioaddr) ? attr->mode : 0; +} + +static const struct attribute_group thermal_extra_group = { + .attrs = thermal_extra_attrs, + .is_visible = thermal_extra_attrs_visible, +}; +__ATTRIBUTE_GROUPS(thermal_extra); + +static int fme_thermal_mgmt_init(struct platform_device *pdev, + struct dfl_feature *feature) +{ + struct device *hwmon; + + dev_dbg(&pdev->dev, "FME Thermal Management Init.\n"); + + /* + * create hwmon to allow userspace monitoring temperature and other + * threshold information. + * + * temp1_input -> FPGA device temperature + * temp1_max -> hardware threshold 1 -> 50% or 90% throttling + * temp1_crit -> hardware threshold 2 -> 100% throttling + * temp1_emergency -> hardware trip_threshold to shutdown FPGA + * temp1_max_alarm -> hardware threshold 1 alarm + * temp1_crit_alarm -> hardware threshold 2 alarm + * + * create device specific sysfs interfaces, e.g. read temp1_max_policy + * to understand the actual hardware throttling action (50% vs 90%). + * + * If hardware doesn't support automatic throttling per thresholds, + * then all above sysfs interfaces are not visible except temp1_input + * for temperature. + */ + hwmon = devm_hwmon_device_register_with_info(&pdev->dev, + "dfl_fme_thermal", feature, + &thermal_hwmon_chip_info, + thermal_extra_groups); + if (IS_ERR(hwmon)) { + dev_err(&pdev->dev, "Fail to register thermal hwmon\n"); + return PTR_ERR(hwmon); + } + + return 0; +} + +static void fme_thermal_mgmt_uinit(struct platform_device *pdev, + struct dfl_feature *feature) +{ + dev_dbg(&pdev->dev, "FME Thermal Management UInit.\n"); +} + +static const struct dfl_feature_id fme_thermal_mgmt_id_table[] = { + {.id = FME_FEATURE_ID_THERMAL_MGMT,}, + {0,} +}; + +static const struct dfl_feature_ops fme_thermal_mgmt_ops = { + .init = fme_thermal_mgmt_init, + .uinit = fme_thermal_mgmt_uinit, +}; + static struct dfl_feature_driver fme_feature_drvs[] = { { .id_table = fme_hdr_id_table, @@ -231,6 +414,10 @@ static long fme_hdr_ioctl(struct platform_device *pdev, .ops = &fme_global_err_ops, }, { + .id_table = fme_thermal_mgmt_id_table, + .ops = &fme_thermal_mgmt_ops, + }, + { .ops = NULL, }, }; -- 1.8.3.1