On Thu, Jun 27, 2019 at 12:53:37PM +0800, Wu Hao wrote:
> 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.
> ---
> 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
>
