Cast get_unaligned_be32(...) to u64 in order to give the compiler
complete information about the proper arithmetic to use and avoid
a potential integer overflow.
Notice that such function call is used in contexts that expect
expressions of type u64 (64 bits, unsigned); and the following
expressions are currently being evaluated using 32-bit
arithmetic:
val = get_unaligned_be32(&power->update_tag) *
occ->powr_sample_time_us;
val = get_unaligned_be32(&power->vdn.update_tag) *
occ->powr_sample_time_us;
Addresses-Coverity-ID: 1442357 ("Unintentional integer overflow")
Addresses-Coverity-ID: 1442476 ("Unintentional integer overflow")
Addresses-Coverity-ID: 1442508 ("Unintentional integer overflow")
Fixes: ff692d80b2e2 ("hwmon (occ): Add sensor types and versions")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The OCC provides a variety of additional information about the state of
the host processor, such as throttling, error conditions, and the number
of OCCs detected in the system. This information is essential to service
processor applications such as fan control and host management.
Therefore, export this data in the form of sysfs attributes attached to
the platform device (to which the hwmon device is also attached).
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Setup the sensor attributes for every OCC sensor found by the first poll
response. Register the attributes with hwmon.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add structures to define all sensor types and versions. Add sysfs show
and store functions for each sensor type. Add a method to construct the
"set user power cap" command and send it to the OCC. Add rate limit to
polling the OCC (in case user-space reads our hwmon entries rapidly).
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Add method to parse the response from the OCC poll command. This only
needs to be done during probe(), since the OCC shouldn't change the
number or format of sensors while it's running. The parsed response
allows quick access to sensor data, as well as information on the
number and version of sensors, which we need to instantiate hwmon
attributes.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
For the P8 OCC, add the procedure to send a command to the OCC over I2C
bus. This involves writing the OCC command registers with serial
communication operations (SCOMs) interpreted by the I2C slave. For the
P9 OCC, add a procedure to use the OCC in-kernel API to send a command
to the OCC through the SBE.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The OCC is a device embedded on a POWER processor that collects and
aggregates sensor data from the processor and system. The OCC can
provide the raw sensor data as well as perform thermal and power
management on the system.
This driver provides a hwmon interface to the OCC from a service
processor (e.g. a BMC). The driver supports both POWER8 and POWER9 OCCs.
Communications with the POWER8 OCC are established over standard I2C
bus. The driver communicates with the POWER9 OCC through the FSI-based
OCC driver, which handles the lower-level communication details.
This patch lays out the structure of the OCC hwmon driver. There are two
platform drivers, one each for P8 and P9 OCCs. These are probed through
the I2C tree and the FSI-based OCC driver, respectively. The patch also
defines the first common structures and methods between the two OCC
versions.
Signed-off-by: Eddie James <eajames@linux.ibm.com>
[groeck: Fix up SPDX license identifier]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Eddie James