PID control configuration usage

[Ed Tanous]

On 3/6/19 11:36 AM, Matthew Barth wrote:
> I'm investigating the functionality and use of pid-control to what is
> currently being used on IBM's witherspoon system.
Sweeeeeet.

> Is there a PID control
> configuration being used that's upstream? I am unable to find any
> systems in the meta layers using pid-control that provides a direct
> configuration example. It looks to be used in the Intel layer that pulls
> a config together from entity-manager and presents it on dbus to
> pid-control, but I dont follow how the entity-manager json transforms to
> the consumable pid-control json.
It doesn't.  When using the entity manager configs, the DBUS data
structures are read directly by pid-control, and converted into the C
data structures that the JSON would've been encoded to at build time.
no json is created or destroyed.

> Could someone point me to a functional
> (possibly in-use) example or show the json config produced from
> entity-manager?
I thought the Quanta system used it, but I'm not seeing the JSON.
Patrick checked in a basic example here:
https://github.com/openbmc/phosphor-pid-control/blob/master/examples/fan-info.json
But I'm guessing you already found that.

I'm not sure if it helps, but here's a dump of the entity-manager dbus
interfaces, on a system with a dozen or so add in fru devices detected.
Each fru device has its own thermal controllers installed and exposed to
dbus.

https://pastebin.com/jaKw5TJa

-Ed