[Skiboot] [PATCH V8 5/8] sensors: occ: Send CSM_{min/max} on min/max sensor read

[Shilpasri G Bhat]

Hi Stewart,

On 07/27/2017 02:24 PM, Stewart Smith wrote:
> Shilpasri G Bhat <shilpa.bhat at linux.vnet.ibm.com> writes:
>> HWMON's lowest/highest attribute is used by CSM agent, so map it to
>> the min/max of CSM.
> 
> I'm unsure to the exact reasoning of this patch?
> 
> I get that we have 3 sets of min/max sensors, but I am unclear as to why
> we change to pick the CSM min/max rather than sample min/max.
> 
> Is there a good reason for it? Do they behave differently?
> 
> 

We actually have 4 sets of min/max sensors owned by OCC, CSM, Profiler and
Job-Scheduler. The difference between OCC and the remaining three is that
'sample min/max' belong to OCC and these cannot be reset, while the remaining
three sets of min/max can be reset using the OPAL-OCC command.

CSM agent reads the sensors using hwmon and the highest/lowest attributes in
hwmon points to CSM min/max, so that's why I am passing CSM's min/max in this
patch here.

I will define CSM min/max in
+enum sensor_attr {
+	SENSOR_SAMPLE,
+	SENSOR_MAX,
+	SENSOR_MIN,
+	MAX_SENSOR_ATTR,
+};

to add SENSOR_CSM_MIN and SENSOR_CSM_MAX and encode the same in the device-tree
for "sensor-data-max" and "sensor-data-min" property.

Thanks and Reagrds,
Shilpa