Guenter Roeck <linux@roeck-us.net> wrote on 01/21/2017 12:18:23 PM:
> On 01/16/2017 01:13 PM, eajames.ibm@gmail.com wrote:
> > From: "Edward A. James" <eajames@us.ibm.com>
> >
> > Add functions to parse the data structures that are specific to the OCC on
> > the POWER8 processor. These are the sensor data structures, including
> > temperature, frequency, power, and "caps."
> >
> > Signed-off-by: Edward A. James <eajames@us.ibm.com>
> > Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
> > ---
> >  Documentation/hwmon/occ    |   9 ++
> >  drivers/hwmon/occ/occ_p8.c | 247 ++++++++++++++++++++++++++++++++
> +++++++++++++
> >  drivers/hwmon/occ/occ_p8.h |  30 ++++++
> >  3 files changed, 286 insertions(+)
> >  create mode 100644 drivers/hwmon/occ/occ_p8.c
> >  create mode 100644 drivers/hwmon/occ/occ_p8.h
> >
> > diff --git a/Documentation/hwmon/occ b/Documentation/hwmon/occ
> > index d0bdf06..143951e 100644
> > --- a/Documentation/hwmon/occ
> > +++ b/Documentation/hwmon/occ
> > @@ -25,6 +25,15 @@ 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.
> >
> > +The format for the POWER8 OCC sensor data can be found in the P8 OCC
> > +specification:
> > +github.com/open-power/docs/blob/master/occ/OCC_OpenPwr_FW_Interfaces.pdf
> > +This document provides the details of the OCC sensors: power, frequency,
> > +temperature, and caps. These sensor formats are specific to the
> POWER8 OCC. A
> > +number of data structures, such as command format, response
> headers, and the
> > +like, are also defined in this specification, and are common to
> both POWER8 and
> > +POWER9 OCCs.
> > +
> >  sysfs Entries
> >  -------------
> >
> > diff --git a/drivers/hwmon/occ/occ_p8.c b/drivers/hwmon/occ/occ_p8.c
> > new file mode 100644
> > index 0000000..32215ed
> > --- /dev/null
> > +++ b/drivers/hwmon/occ/occ_p8.c
> > @@ -0,0 +1,247 @@
> > +/*
> > + * occ_p8.c - OCC hwmon driver
> > + *
> > + * This file contains the Power8-specific methods and data structures for
> > + * the OCC hwmon driver.
> > + *
> > + * 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 <asm/unaligned.h>
> > +#include <linux/device.h>
> > +#include <linux/err.h>
> > +#include <linux/hwmon.h>
> > +#include <linux/init.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/slab.h>
> > +#include "occ.h"
> > +#include "occ_p8.h"
> > +
> > +/* P8 OCC sensor data format */
> > +struct p8_occ_sensor {
> > +   u16 sensor_id;
> > +   u16 value;
> > +};
> > +
> > +struct p8_power_sensor {
> > +   u16 sensor_id;
> > +   u32 update_tag;
> > +   u32 accumulator;
> > +   u16 value;
> > +};
> > +
> > +struct p8_caps_sensor {
> > +   u16 curr_powercap;
> > +   u16 curr_powerreading;
> > +   u16 norm_powercap;
> > +   u16 max_powercap;
> > +   u16 min_powercap;
> > +   u16 user_powerlimit;
> > +};
> > +
> > +static const u32 p8_sensor_hwmon_configs[MAX_OCC_SENSOR_TYPE] = {
> > +   HWMON_I_INPUT | HWMON_I_LABEL,   /* freq: value | label */
> > +   HWMON_T_INPUT | HWMON_T_LABEL,   /* temp: value | label */
> > +   /* power: value | label | accumulator | update_tag */
> > +   HWMON_P_INPUT | HWMON_P_LABEL | HWMON_P_AVERAGE |
> > +      HWMON_P_AVERAGE_INTERVAL,
> > +   /* caps: curr | max | min | norm | user */
> > +   HWMON_P_CAP | HWMON_P_CAP_MAX | HWMON_P_CAP_MIN | HWMON_P_MAX |
> > +      HWMON_P_ALARM,
> > +};
> > +
> > +void p8_parse_sensor(u8 *data, void *sensor, int sensor_type, int off,
> > +           int snum)
> > +{
> > +   switch (sensor_type) {
> > +   case FREQ:
> > +   case TEMP:
> > +   {
> > +      struct p8_occ_sensor *os =
> > +         &(((struct p8_occ_sensor *)sensor)[snum]);
> > +
> > +      os->sensor_id = be16_to_cpu(get_unaligned((u16 *)&data[off]));
> > +      os->value = be16_to_cpu(get_unaligned((u16 *)&data[off + 2]));
> > +   }
> > +      break;
> > +   case POWER:
> > +   {
> > +      struct p8_power_sensor *ps =
> > +         &(((struct p8_power_sensor *)sensor)[snum]);
> > +
> > +      ps->sensor_id = be16_to_cpu(get_unaligned((u16 *)&data[off]));
> > +      ps->update_tag =
> > +         be32_to_cpu(get_unaligned((u32 *)&data[off + 2]));
> > +      ps->accumulator =
> > +         be32_to_cpu(get_unaligned((u32 *)&data[off + 6]));
> > +      ps->value = be16_to_cpu(get_unaligned((u16 *)&data[off + 10]));
> > +   }
> > +      break;
> > +   case CAPS:
> > +   {
> > +      struct p8_caps_sensor *cs =
> > +         &(((struct p8_caps_sensor *)sensor)[snum]);
> > +
> > +      cs->curr_powercap =
> > +         be16_to_cpu(get_unaligned((u16 *)&data[off]));
> > +      cs->curr_powerreading =
> > +         be16_to_cpu(get_unaligned((u16 *)&data[off + 2]));
> > +      cs->norm_powercap =
> > +         be16_to_cpu(get_unaligned((u16 *)&data[off + 4]));
> > +      cs->max_powercap =
> > +         be16_to_cpu(get_unaligned((u16 *)&data[off + 6]));
> > +      cs->min_powercap =
> > +         be16_to_cpu(get_unaligned((u16 *)&data[off + 8]));
> > +      cs->user_powerlimit =
> > +         be16_to_cpu(get_unaligned((u16 *)&data[off + 10]));
> > +   }
> > +      break;
> > +   };
> > +}
> > +
> > +void *p8_alloc_sensor(int sensor_type, int num_sensors)
> > +{
> > +   switch (sensor_type) {
> > +   case FREQ:
> > +   case TEMP:
> > +      return kcalloc(num_sensors, sizeof(struct p8_occ_sensor),
> > +                GFP_KERNEL);
> > +   case POWER:
> > +      return kcalloc(num_sensors, sizeof(struct p8_power_sensor),
> > +                GFP_KERNEL);
> > +   case CAPS:
> > +      return kcalloc(num_sensors, sizeof(struct p8_caps_sensor),
> > +                GFP_KERNEL);
> > +   default:
> > +      return NULL;
> > +   }
> > +}
> > +
> > +int p8_get_sensor(struct occ *driver, int sensor_type, int sensor_num,
> > +        u32 hwmon, long *val)
> > +{
> > +   int rc = 0;
> > +   void *sensor;
> > +
> > +   if (sensor_type == POWER) {
> > +      if (hwmon == hwmon_power_cap || hwmon == hwmon_power_cap_max ||
> > +          hwmon == hwmon_power_cap_min || hwmon == hwmon_power_max ||
> > +          hwmon == hwmon_power_alarm)
> > +         sensor_type = CAPS;
> > +   }
> > +
> > +   sensor = occ_get_sensor(driver, sensor_type);
> > +   if (!sensor)
> > +      return -ENODEV;
> > +
> > +   switch (sensor_type) {
> > +   case FREQ:
> > +   case TEMP:
> > +   {
> > +      struct p8_occ_sensor *os =
> > +         &(((struct p8_occ_sensor *)sensor)[sensor_num]);
> > +
> > +      if (hwmon == hwmon_in_input || hwmon == hwmon_temp_input)
> > +         *val = os->value;
> > +      else if (hwmon == hwmon_in_label || hwmon == hwmon_temp_label)
> > +         *val = os->sensor_id;
>
> Guess that explains the numeric labels I wondered about earlier. Are
> you really sure
> you want to have such numbered labels, ie temp1_label = "1" and so
> on ? Your call,
> really, just wondering.


Yes, that is our requirement I think. They aren't just arbitrary numbers,
the sensor_id is read off the OCC. It corresponds to some identifier that
users can look up on our side with the OCC documentation. It is pretty
meaningless in the driver though, agreed. But it's system-specific, so
without a bunch of tables stored in the driver, not sure what else we
could do.

Thanks,

Eddie

>
> > +      else
> > +         rc = -EOPNOTSUPP;
> > +   }
> > +      break;
> > +   case POWER:
> > +   {
> > +      struct p8_power_sensor *ps =
> > +         &(((struct p8_power_sensor *)sensor)[sensor_num]);
> > +
> > +      switch (hwmon) {
> > +      case hwmon_power_input:
> > +         *val = ps->value;
> > +         break;
> > +      case hwmon_power_label:
> > +         *val = ps->sensor_id;
> > +         break;
> > +      case hwmon_power_average:
> > +         *val = ps->accumulator;
> > +         break;
> > +      case hwmon_power_average_interval:
> > +         *val = ps->update_tag;
> > +         break;
> > +      default:
> > +         rc = -EOPNOTSUPP;
> > +      }
> > +   }
> > +      break;
> > +   case CAPS:
> > +   {
> > +      struct p8_caps_sensor *cs =
> > +         &(((struct p8_caps_sensor *)sensor)[sensor_num]);
> > +
> > +      switch (hwmon) {
> > +      case hwmon_power_cap:
> > +         *val = cs->curr_powercap;
> > +         break;
> > +      case hwmon_power_cap_max:
> > +         *val = cs->max_powercap;
> > +         break;
> > +      case hwmon_power_cap_min:
> > +         *val = cs->min_powercap;
> > +         break;
> > +      case hwmon_power_max:
> > +         *val = cs->norm_powercap;
> > +         break;
> > +      case hwmon_power_alarm:
> > +         *val = cs->user_powerlimit;
> > +         break;
> > +      default:
> > +         rc = -EOPNOTSUPP;
> > +      }
> > +   }
> > +      break;
> > +   default:
> > +      rc = -EINVAL;
> > +   }
> > +
> > +   return rc;
> > +}
> > +
> > +static const struct occ_ops p8_ops = {
> > +   .parse_sensor = p8_parse_sensor,
> > +   .alloc_sensor = p8_alloc_sensor,
> > +   .get_sensor = p8_get_sensor,
> > +};
> > +
> > +static const struct occ_config p8_config = {
> > +   .command_addr = 0xFFFF6000,
> > +   .response_addr = 0xFFFF7000,
> > +};
> > +
> > +const u32 *p8_get_sensor_hwmon_configs()
> > +{
> > +   return p8_sensor_hwmon_configs;
> > +}
> > +EXPORT_SYMBOL(p8_get_sensor_hwmon_configs);
> > +
> > +struct occ *p8_occ_start(struct device *dev, void *bus,
> > +          struct occ_bus_ops *bus_ops)
> > +{
> > +   return occ_start(dev, bus, bus_ops, &p8_ops, &p8_config);
> > +}
> > +EXPORT_SYMBOL(p8_occ_start);
> > +
> > +MODULE_AUTHOR("Eddie James <eajames@us.ibm.com>");
> > +MODULE_DESCRIPTION("P8 OCC sensors");
> > +MODULE_LICENSE("GPL");
> > diff --git a/drivers/hwmon/occ/occ_p8.h b/drivers/hwmon/occ/occ_p8.h
> > new file mode 100644
> > index 0000000..3fe6417
> > --- /dev/null
> > +++ b/drivers/hwmon/occ/occ_p8.h
> > @@ -0,0 +1,30 @@
> > +/*
> > + * occ_p8.h - OCC hwmon driver
> > + *
> > + * This file contains Power8-specific function prototypes
> > + *
> > + * 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_P8_H__
> > +#define __OCC_P8_H__
> > +
> > +#include "scom.h"
> > +
> > +struct device;
> > +
> > +const u32 *p8_get_sensor_hwmon_configs(void);
> > +struct occ *p8_occ_start(struct device *dev, void *bus,
> > +          struct occ_bus_ops *bus_ops);
> > +
> > +#endif /* __OCC_P8_H__ */
> >
>