On 01/16/2017 01:13 PM, eajames.ibm@xxxxxxxxx wrote:
From: "Edward A. James" <eajames@xxxxxxxxxx> Add a generic mechanism to expose the sensors provided by the OCC in sysfs. Signed-off-by: Edward A. James <eajames@xxxxxxxxxx> Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx> --- Documentation/hwmon/occ | 62 ++++++++++ drivers/hwmon/occ/Makefile | 2 +- drivers/hwmon/occ/occ_sysfs.c | 271 ++++++++++++++++++++++++++++++++++++++++++ drivers/hwmon/occ/occ_sysfs.h | 44 +++++++ 4 files changed, 378 insertions(+), 1 deletion(-) create mode 100644 drivers/hwmon/occ/occ_sysfs.c create mode 100644 drivers/hwmon/occ/occ_sysfs.h diff --git a/Documentation/hwmon/occ b/Documentation/hwmon/occ index 79d1642..d0bdf06 100644 --- a/Documentation/hwmon/occ +++ b/Documentation/hwmon/occ @@ -25,6 +25,68 @@ Currently, all versions of the OCC support four types of sensor data: power, temperature, frequency, and "caps," which indicate limits and thresholds used internally on the OCC. +sysfs Entries +------------- + +The OCC driver uses the hwmon sysfs framework to provide data to userspace. + +The driver exports a number of sysfs files for each type of sensor. The +sensor-specific files vary depending on the processor type, though many of the +attributes are common for both the POWER8 and POWER9. + +The hwmon interface cannot define every type of sensor that may be used. +Therefore, the frequency sensor on the OCC uses the "input" type sensor defined +by the hwmon interface, rather than defining a new type of custom sensor. + +Below are detailed the names and meaning of each sensor file for both types of +processors. All sensors are read-only unless otherwise specified. <x> indicates +the hwmon index. sensor id indicates the unique internal OCC identifer. Please +see the POWER OCC specification for details on all these sensor values. + +frequency: + all processors: + in<x>_input - frequency value + in<x>_label - sensor id +temperature: + POWER8: + temp<x>_input - temperature value + temp<x>_label - sensor id + POWER9 (in addition to above): + temp<x>_type - FRU type + +power: + POWER8: + power<x>_input - power value + power<x>_label - sensor id + power<x>_average - accumulator + power<x>_average_interval - update tag (number of samples in + accumulator) + POWER9: + power<x>_input - power value + power<x>_label - sensor id + power<x>_average_min - accumulator[0] + power<x>_average_max - accumulator[1] (64 bits total) + power<x>_average_interval - update tag + power<x>_reset_history - (function_id | (apss_channel << 8) + +caps: + POWER8: + power<x>_cap - current powercap + power<x>_cap_max - max powercap + power<x>_cap_min - min powercap + power<x>_max - normal powercap + power<x>_alarm - user powercap, r/w + POWER9: + power<x>_cap_alarm - user powercap source + +The driver also provides two sysfs entries through hwmon to better +control the driver and monitor the master OCC. Though there may be multiple +OCCs present on the system, these two files are only present for the "master" +OCC. + name - read the name of the driver + update_interval - read or write the minimum interval for polling the + OCC. + BMC - Host Communications ------------------------- diff --git a/drivers/hwmon/occ/Makefile b/drivers/hwmon/occ/Makefile index 93cb52f..a6881f9 100644 --- a/drivers/hwmon/occ/Makefile +++ b/drivers/hwmon/occ/Makefile @@ -1 +1 @@ -obj-$(CONFIG_SENSORS_PPC_OCC) += occ.o +obj-$(CONFIG_SENSORS_PPC_OCC) += occ.o occ_sysfs.o diff --git a/drivers/hwmon/occ/occ_sysfs.c b/drivers/hwmon/occ/occ_sysfs.c new file mode 100644 index 0000000..2f20c40 --- /dev/null +++ b/drivers/hwmon/occ/occ_sysfs.c @@ -0,0 +1,271 @@ +/* + * occ_sysfs.c - OCC sysfs interface + * + * This file contains the methods and data structures for implementing the OCC + * hwmon sysfs entries. + * + * Copyright 2016 IBM Corp. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/init.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include "occ.h" +#include "occ_sysfs.h" + +#define RESP_RETURN_CMD_INVAL 0x13 + +static int occ_hwmon_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + int rc = 0;
Unnecessary initialization.
+ struct occ_sysfs *driver = dev_get_drvdata(dev); + struct occ *occ = driver->occ; + + switch (type) { + case hwmon_in: + rc = occ_get_sensor_value(occ, FREQ, channel, attr, val); + break; + case hwmon_temp: + rc = occ_get_sensor_value(occ, TEMP, channel, attr, val); + break; + case hwmon_power: + rc = occ_get_sensor_value(occ, POWER, channel, attr, val); + break; + default: + rc = -EOPNOTSUPP; + } + + return rc; +} + +static int occ_hwmon_read_string(struct device *dev, + enum hwmon_sensor_types type, u32 attr, + int channel, char **str) +{ + int rc; + unsigned long val = 0; + + if (!((type == hwmon_in && attr == hwmon_in_label) || + (type == hwmon_temp && attr == hwmon_temp_label) || + (type == hwmon_power && attr == hwmon_power_label))) + return -EOPNOTSUPP; + + rc = occ_hwmon_read(dev, type, attr, channel, &val); + if (rc < 0) + return rc; + + rc = snprintf(*str, PAGE_SIZE - 1, "%ld", val);
val is unsigned long. I am quite confused what this is for, though. The function is used for string attributes, or in other words for labels. What is the benefit of having a label that returns the same data as the value attribute ? Is this maybe a misunderstanding ?
+ if (rc > 0) + rc = 0; + + return rc; +} + +static int occ_hwmon_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + int rc = 0; + struct occ_sysfs *driver = dev_get_drvdata(dev); + + if (type == hwmon_chip && attr == hwmon_chip_update_interval) { + occ_set_update_interval(driver->occ, val);
As mentioned in the other patch, please drop. This is not the intended use case for this attribute.
+ return 0; + } else if (type == hwmon_power && attr == hwmon_power_alarm) { + rc = occ_set_user_powercap(driver->occ, val); + if (rc) { + if (rc == RESP_RETURN_CMD_INVAL) { + dev_err(dev, + "set invalid powercap value: %ld\n", + val); + return -EINVAL; + } + + dev_err(dev, "set user powercap failed: 0x:%x\n", rc); + return rc; + } + + driver->user_powercap = val; + + return rc; + } + + return -EOPNOTSUPP; +} + +static umode_t occ_is_visible(const void *data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + const struct occ_sysfs *driver = data; + + switch (type) { + case hwmon_chip: + if (attr == hwmon_chip_update_interval) + return S_IRUGO | S_IWUSR; + break; + case hwmon_in: + if (BIT(attr) & driver->sensor_hwmon_configs[0]) + return S_IRUGO; + break; + case hwmon_temp: + if (BIT(attr) & driver->sensor_hwmon_configs[1]) + return S_IRUGO; + break; + case hwmon_power: + /* user power limit */ + if (attr == hwmon_power_alarm) + return S_IRUGO | S_IWUSR; + else if ((BIT(attr) & driver->sensor_hwmon_configs[2]) || + (BIT(attr) & driver->sensor_hwmon_configs[3])) + return S_IRUGO; + break; + default: + return 0;
Might as well use break; here for consistency.
+ } + + return 0; +} + +static const struct hwmon_ops occ_hwmon_ops = { + .is_visible = occ_is_visible, + .read = occ_hwmon_read, + .read_string = occ_hwmon_read_string, + .write = occ_hwmon_write, +}; + +static const u32 occ_chip_config[] = { + HWMON_C_UPDATE_INTERVAL, + 0 +}; + +static const struct hwmon_channel_info occ_chip = { + .type = hwmon_chip, + .config = occ_chip_config +}; + +static const enum hwmon_sensor_types occ_sensor_types[MAX_OCC_SENSOR_TYPE] = { + hwmon_in, + hwmon_temp, + hwmon_power, + hwmon_power +}; + +struct occ_sysfs *occ_sysfs_start(struct device *dev, struct occ *occ, + const u32 *sensor_hwmon_configs, + const char *name) +{ + bool master_occ = false; + int rc, i, j, sensor_num, index = 0, id; + char *brk; + struct occ_blocks *resp = NULL; + u32 *sensor_config; + struct occ_sysfs *hwmon = devm_kzalloc(dev, sizeof(struct occ_sysfs), + GFP_KERNEL); + if (!hwmon) + return ERR_PTR(-ENOMEM); + + /* need space for null-termination and occ chip */ + hwmon->occ_sensors = + devm_kzalloc(dev, sizeof(struct hwmon_channel_info *) * + (MAX_OCC_SENSOR_TYPE + 2), GFP_KERNEL); + if (!hwmon->occ_sensors) + return ERR_PTR(-ENOMEM); + + hwmon->occ = occ; + hwmon->sensor_hwmon_configs = (u32 *)sensor_hwmon_configs;
Either this is a const or it isn't. If it isn't, it should not be passed in as const. If it is, it can be declared const in struct occ_sysfs.
+ hwmon->occ_info.ops = &occ_hwmon_ops; + hwmon->occ_info.info = + (const struct hwmon_channel_info **)hwmon->occ_sensors;
Why is this typecast needed ?
+ + occ_get_response_blocks(occ, &resp); + + for (i = 0; i < MAX_OCC_SENSOR_TYPE; ++i) + resp->sensor_block_id[i] = -1; + + /* read sensor data from occ */ + rc = occ_update_device(occ); + if (rc) { + dev_err(dev, "cannot get occ sensor data: %d\n", rc); + return ERR_PTR(rc); + } + if (!resp->blocks) + return ERR_PTR(-ENOMEM); + + master_occ = resp->sensor_block_id[CAPS] >= 0; + + for (i = 0; i < MAX_OCC_SENSOR_TYPE; i++) { + id = resp->sensor_block_id[i]; + if (id < 0) + continue; + + sensor_num = resp->blocks[id].header.sensor_num; + /* need null-termination */ + sensor_config = devm_kzalloc(dev, + sizeof(u32) * (sensor_num + 1), + GFP_KERNEL); + if (!sensor_config) + return ERR_PTR(-ENOMEM); + + for (j = 0; j < sensor_num; j++) + sensor_config[j] = sensor_hwmon_configs[i]; + + hwmon->occ_sensors[index] = + devm_kzalloc(dev, sizeof(struct hwmon_channel_info), + GFP_KERNEL); + if (!hwmon->occ_sensors[index]) + return ERR_PTR(-ENOMEM); + + hwmon->occ_sensors[index]->type = occ_sensor_types[i]; + hwmon->occ_sensors[index]->config = sensor_config; + index++; + }
I had the impression from patch 1 that the number of sensors can change at runtime. If so, this doesn't really work well; the sysfs attributes won't be updated in this case. Can it really happen that the sensor information can change ?
+ + /* only need one of these for any number of occs */ + if (master_occ) + hwmon->occ_sensors[index] = + (struct hwmon_channel_info *)&occ_chip;
Why this typecast ?
+ + /* search for bad chars */ + strncpy(hwmon->hwmon_name, name, OCC_HWMON_NAME_LENGTH); + brk = strpbrk(hwmon->hwmon_name, "-* \t\n"); + while (brk) { + *brk = '_'; + brk = strpbrk(brk, "-* \t\n"); + } + + hwmon->dev = devm_hwmon_device_register_with_info(dev, + hwmon->hwmon_name, + hwmon, + &hwmon->occ_info, + NULL); + if (IS_ERR(hwmon->dev)) { + dev_err(dev, "cannot register hwmon device %s: %ld\n", + hwmon->hwmon_name, PTR_ERR(hwmon->dev)); + return ERR_CAST(hwmon->dev); + } + + return hwmon; +} +EXPORT_SYMBOL(occ_sysfs_start); + +MODULE_AUTHOR("Eddie James <eajames@xxxxxxxxxx>"); +MODULE_DESCRIPTION("OCC sysfs driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/hwmon/occ/occ_sysfs.h b/drivers/hwmon/occ/occ_sysfs.h new file mode 100644 index 0000000..7de92e7 --- /dev/null +++ b/drivers/hwmon/occ/occ_sysfs.h @@ -0,0 +1,44 @@ +/* + * occ_sysfs.h - OCC sysfs interface + * + * This file contains the data structures and function prototypes for the OCC + * hwmon sysfs entries. + * + * Copyright 2016 IBM Corp. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef __OCC_SYSFS_H__ +#define __OCC_SYSFS_H__ + +#include <linux/hwmon.h> + +struct occ; +struct device; + +#define OCC_HWMON_NAME_LENGTH 32 + +struct occ_sysfs { + struct device *dev; + struct occ *occ; + + char hwmon_name[OCC_HWMON_NAME_LENGTH + 1]; + u32 *sensor_hwmon_configs; + struct hwmon_channel_info **occ_sensors; + struct hwmon_chip_info occ_info; + u16 user_powercap; +};
Is this information used outside the sysfs code ? If not, it should be defined in the source file and not be available outside of it.
+ +struct occ_sysfs *occ_sysfs_start(struct device *dev, struct occ *occ, + const u32 *sensor_hwmon_configs, + const char *name); +#endif /* __OCC_SYSFS_H__ */
-- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html