On Mon, Apr 29, 2019 at 4:13 AM Wu Hao <hao.wu@xxxxxxxxx> wrote: + The hwmon people > > 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_alarm/ crit/ emergency), threshold status (temp1_alarm_status/ > temp1_crit_status) and throttling policy (temp1_alarm_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> > --- > 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 > --- > Documentation/ABI/testing/sysfs-platform-dfl-fme | 64 +++++++ > drivers/fpga/Kconfig | 2 +- > drivers/fpga/dfl-fme-main.c | 212 +++++++++++++++++++++++ > 3 files changed, 277 insertions(+), 1 deletion(-) > > diff --git a/Documentation/ABI/testing/sysfs-platform-dfl-fme b/Documentation/ABI/testing/sysfs-platform-dfl-fme > index d1aa375..dfbd315 100644 > --- a/Documentation/ABI/testing/sysfs-platform-dfl-fme > +++ b/Documentation/ABI/testing/sysfs-platform-dfl-fme > @@ -44,3 +44,67 @@ Description: Read-only. It returns socket_id to indicate which socket > this FPGA belongs to, only valid for integrated solution. > User only needs this information, in case standard numa node > can't provide correct information. > + > +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/name > +Date: April 2019 > +KernelVersion: 5.2 > +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: April 2019 > +KernelVersion: 5.2 > +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_alarm > +Date: April 2019 > +KernelVersion: 5.2 > +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_alarm_policy'). > + > +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_crit > +Date: April 2019 > +KernelVersion: 5.2 > +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: April 2019 > +KernelVersion: 5.2 > +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_alarm_status > +Date: April 2019 > +KernelVersion: 5.2 > +Contact: Wu Hao <hao.wu@xxxxxxxxx> > +Description: Read-only. It returns 1 if temperature is currently at or above > + hardware threshold1 (see 'temp1_alarm'), otherwise 0. > + > +What: /sys/bus/platform/devices/dfl-fme.0/hwmon/hwmonX/temp1_crit_status > +Date: April 2019 > +KernelVersion: 5.2 > +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_alarm_policy > +Date: April 2019 > +KernelVersion: 5.2 > +Contact: Wu Hao <hao.wu@xxxxxxxxx> > +Description: Read-Only. Read this file to get the policy of hardware threshold1 > + (see 'temp1_alarm'). 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 c20445b..a6d7588 100644 > --- a/drivers/fpga/Kconfig > +++ b/drivers/fpga/Kconfig > @@ -154,7 +154,7 @@ 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 8339ee8..b9a68b8 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 +219,212 @@ 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_alarm: > + 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; > + 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 u32 thermal_hwmon_temp_config[] = { > + HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_CRIT | HWMON_T_EMERGENCY, > + 0 > +}; > + > +static const struct hwmon_channel_info hwmon_temp_info = { > + .type = hwmon_temp, > + .config = thermal_hwmon_temp_config, > +}; > + > +static const struct hwmon_channel_info *thermal_hwmon_info[] = { > + &hwmon_temp_info, > + NULL > +}; > + > +static const struct hwmon_chip_info thermal_hwmon_chip_info = { > + .ops = &thermal_hwmon_ops, > + .info = thermal_hwmon_info, > +}; > + > +static ssize_t temp1_alarm_status_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 scnprintf(buf, PAGE_SIZE, "%u\n", > + (unsigned int)FIELD_GET(TEMP_THRESHOLD1_STATUS, v)); > +} > + > +static ssize_t temp1_crit_status_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 scnprintf(buf, PAGE_SIZE, "%u\n", > + (unsigned int)FIELD_GET(TEMP_THRESHOLD2_STATUS, v)); > +} > + > +static ssize_t temp1_alarm_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 scnprintf(buf, PAGE_SIZE, "%u\n", > + (unsigned int)FIELD_GET(TEMP_THRESHOLD1_POLICY, v)); > +} > + > +static DEVICE_ATTR_RO(temp1_alarm_status); > +static DEVICE_ATTR_RO(temp1_crit_status); > +static DEVICE_ATTR_RO(temp1_alarm_policy); > + > +static struct attribute *thermal_extra_attrs[] = { > + &dev_attr_temp1_alarm_status.attr, > + &dev_attr_temp1_crit_status.attr, > + &dev_attr_temp1_alarm_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_alarm -> hardware threshold 1 -> 50% or 90% throttling > + * temp1_crit -> hardware threshold 2 -> 100% throttling > + * temp1_emergency -> hardware trip_threshold to shutdown FPGA > + * > + * create device specific sysfs interfaces, e.g. read temp1_alarm_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, > @@ -227,6 +435,10 @@ static long fme_hdr_ioctl(struct platform_device *pdev, > .ops = &fme_pr_mgmt_ops, > }, > { > + .id_table = fme_thermal_mgmt_id_table, > + .ops = &fme_thermal_mgmt_ops, > + }, > + { > .ops = NULL, > }, > }; > -- > 1.8.3.1 >