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 | 253
++++++++++++++++++++++++++++++++++++++++++
drivers/hwmon/occ/occ_sysfs.h | 25 +++++
4 files changed, 341 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 d1c863b..580af26 100644
--- a/Documentation/hwmon/occ
+++ b/Documentation/hwmon/occ
@@ -27,6 +27,68 @@ 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 3ed79a5..67b5367 100644
--- a/drivers/hwmon/occ/Makefile
+++ b/drivers/hwmon/occ/Makefile
@@ -1 +1 @@
-obj-$(CONFIG_SENSORS_IBM_OCC) += occ.o
+obj-$(CONFIG_SENSORS_IBM_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..50b20e2
--- /dev/null
+++ b/drivers/hwmon/occ/occ_sysfs.c
@@ -0,0 +1,253 @@
+/*
+ * occ_sysfs.c - OCC sysfs interface
+ *
+ * This file contains the methods and data structures for
implementing the OCC
+ * hwmon sysfs entries.
+ *
+ * Copyright 2017 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.
+ */
+
+#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 OCC_HWMON_NAME_LENGTH 32
+
+struct occ_sysfs {
+ struct device *dev;
+ struct occ *occ;
+
+ char label_buffer[OCC_HWMON_NAME_LENGTH + 1];
+ char hwmon_name[OCC_HWMON_NAME_LENGTH + 1];
+ const u32 *sensor_hwmon_configs;
+ struct hwmon_channel_info **occ_sensors;
+ struct hwmon_chip_info occ_info;
+ u16 user_powercap;
+};
+
+static int occ_hwmon_read(struct device *dev, enum
hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ int rc;
+ struct occ_sysfs *driver = dev_get_drvdata(dev);
+ struct occ *occ = driver->occ;
+
+ switch (type) {
+ case hwmon_in:
+ rc = occ_get_sensor_field(occ, FREQ, channel, attr, val);
+ break;
+ case hwmon_temp:
+ rc = occ_get_sensor_field(occ, TEMP, channel, attr, val);
+ break;
+ case hwmon_power:
+ rc = occ_get_sensor_field(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, const char **str)
+{
+ int rc;
+ unsigned long val = 0;
+ struct occ_sysfs *driver = dev_get_drvdata(dev);
+
+ if (!((type == hwmon_in && attr == hwmon_in_label) ||
+ (type == hwmon_temp && attr == hwmon_temp_label) ||
+ (type == hwmon_power && attr == hwmon_power_label)))
+ return -EOPNOTSUPP;
+
+ /* will fetch the "label", the sensor_id */
+ rc = occ_hwmon_read(dev, type, attr, channel, &val);
+ if (rc < 0)
+ return rc;
+
+ /* just use one label buffer for all sensors. works with current
hwmon
+ * implementation. only alternative is to store a buffer for each
+ * sensor, which gets expensive quickly.
+ */
