Re: [EXT] Re: OpenBMC Sensors

[Vijay Khemka <vijaykhemka@fb.com>]

Aron,
You may also want to look at dbus-sensors as well. This is another approach for sensors through dbus. You have to include entity manager for this approach.

Regards
-Vijay

On 1/31/19, 9:18 PM, "openbmc on behalf of Aaron Williams" <openbmc-bounces+vijaykhemka=fb.com@lists.ozlabs.org on behalf of awilliams@marvell.com> wrote:

    Thanks,
    
    I think I know what I need to do, after looking at the config example and 
    other yaml examples I've found. My problem is I haven't been able to find any 
    example recipes and whatnot that use this (or maybe I'm looking at the wrong 
    things). I've looked at the various implementations but don't see anything 
    using this.
    
    -Aaron
    
    On Thursday, January 31, 2019 7:30:04 AM PST Patrick Venture wrote:
    > On Wed, Jan 30, 2019 at 8:49 PM Emily Shaffer <emilyshaffer@google.com> 
    wrote:
    > > Aaron,
    > > 
    > > If it's complaining at build time it's what it says on the box - you
    > > probably need to include the recipe which builds
    > > phosphor-fans-sensor-inventory.
    > > 
    > > Emily
    > > 
    > > On Wed, Jan 30, 2019, 8:17 PM Aaron Williams <awilliams@marvell.com> 
    wrote:
    > >> Hi Emily,
    > >> 
    > >> I'm still not sure how to go about using this, I'm still fairly new to
    > >> OpenBMC. It's complaing about nothing providing
    > >> 'virtual/phosphor-fans-sensor- inventory'.  I included
    > >> phosphor-pid-control as one of our dependencies.
    > Per Emily, you'll need to implement a recipe that defines the PID
    > inputs.  It sounds like you have two PID loops.  One is the
    > temperature sensor, and that feeds the set-point for the fans, which
    > are a second PID loop.  The idea being, the temperature pid loop
    > attempts to maintain the temperature under (or over) some set-point,
    > and it'll in turn try to get the fans to speed up when necessary.
    > 
    > >> -Aaron
    > >> 
    > >> On Wednesday, January 30, 2019 1:48:10 PM PST you wrote:
    > >> > Great, best luck Aaron. Thanks!
    > >> > 
    > >> > On Wed, Jan 30, 2019, 1:47 PM Aaron Williams <awilliams@marvell.com> 
    wrote:
    > >> > > Hi Emily,
    > >> > > 
    > >> > > Thank you, I will look into it. I don't think losing the sensors when
    > >> > > we
    > >> > > cut
    > >> > > power to the host CPU will be much of an issue. I was just notified
    > >> > > of a
    > >> > > change to our CPLD that will allow the BMC to keep the sensors
    > >> > > powered. At
    > >> > > the
    > >> > > moment, cutting power shuts of the power from the ATX power supply
    > >> > > but now
    > 
    > As far as the sensors when the try is powered down, that's pretty
    > common.  The hwmon driver on the BMC will just be unable to read the
    > values, and you can deal with that in phosphor-hwmon a couple ways.
    > Phosphor-pid-control will go into fail-safe mode if it doesn't receive
    > a sensor value frequently enough.  This mode would cause it to drive
    > the fans to a pre-defined set-point per a configuration.
    > 
    > >> > > I
    > >> > > will have more fine-grained power control. Now I just have to figure
    > >> > > out
    > >> > > how
    > >> > > to update the Lattice CPLD from the BMC... I found some code in the
    > >> > > Facebook
    > >> > > OpenBMC which hopefully I can port over.
    > >> > > 
    > >> > > -Aaron
    > >> > > 
    > >> > > On Wednesday, January 30, 2019 1:42:40 PM PST Emily Shaffer wrote:
    > >> > > > Aaron, we use this daemon for local (to BMC) thermal control:
    > >> > > > https://github.com/openbmc/phosphor-pid-control
    > >> > > > Maybe you'll find it helpful.
    > >> > > > 
    > >> > > > Although I'm not sure how to help you with losing sensors when the
    > >> > > > host
    > >> > > > powers down but the BMC is expected to continue to cool the tray.
    > >> > > > Sounds
    > >> > > > like an issue with the board design, unless I'm not understanding
    > >> > > > what
    > >> > > > you're saying.
    > >> > > > 
    > >> > > > On Wed, Jan 30, 2019 at 1:28 PM Aaron Williams
    > >> > > > <awilliams@marvell.com>
    > >> > > > 
    > >> > > > wrote:
    > >> > > > > Hi Emily,
    > >> > > > > 
    > >> > > > > That's what I need the temperature for. We have two controllers,
    > >> > > > > one
    > >> > > 
    > >> > > that
    > >> > > 
    > >> > > > > monitors the core temperature (a TI TMP421) and one that controls
    > >> > > > > the
    > >> > > 
    > >> > > fans
    > >> > > 
    > >> > > > > (ADT7462). In order to maintain the thermal envelope the TMP421
    > >> > > > > needs
    > >> > > 
    > >> > > to
    > >> > > 
    > >> > > > > be
    > >> > > > > monitored to adjust the fan speed through the ADT7462.
    > >> > > > > 
    > >> > > > > Further complicating things is the fact that these sensors
    > >> > > > > disappear
    > >> > > 
    > >> > > when
    > >> > > 
    > >> > > > > the
    > >> > > > > host is powered down.
    > >> > > > > 
    > >> > > > > -Aaron
    > >> > > > > 
    > >> > > > > On Wednesday, January 30, 2019 9:49:32 AM PST Emily Shaffer 
    wrote:
    > >> > > > > > External Email
    > >> > > 
    > >> > > ---------------------------------------------------------------------
    > >> > > -
    > >> > > 
    > >> > > > > > Hi Aaron,
    > >> > > > > > 
    > >> > > > > > Note that you only really need to worry about sending the
    > >> > > > > > temperature
    > >> > > > > > via
    > >> > > > > > IPMI if you want to send it somewhere besides the BMC.  If you
    > >> > > > > > plan
    > >> > > 
    > >> > > to
    > >> > > 
    > >> > > > > > do
    > >> > > > > > internal thermal control (BMC reads temperature, BMC adjusts
    > >> > > > > > fans
    > >> > > > > > accordingly) you probably don't need IPMI config and can get
    > >> > > > > > away
    > >> > > 
    > >> > > with
    > >> > > 
    > >> > > > > > setting it up as far as DBus in the sensor architecture doc Lei
    > >> > > > > > sent.
    > >> > > > > > 
    > >> > > > > > Emily
    > >> > > > > > 
    > >> > > > > > On Thu, Jan 24, 2019 at 1:27 AM Lei YU <mine260309@gmail.com> 
    wrote:
    > >> > > > > > > On Thu, Jan 24, 2019 at 5:13 PM Aaron Williams <
    > >> > > 
    > >> > > awilliams@marvell.com>
    > >> > > 
    > >> > > > > > > wrote:
    > >> > > > > > > > I see how to set up the hwmon portion defining the devices
    > >> > > > > > > > based
    > >> > > 
    > >> > > on
    > >> > > 
    > >> > > > > the
    > >> > > > > 
    > >> > > > > > > device
    > >> > > > > > > 
    > >> > > > > > > > tree, but I am unsure how to go about configuring the YAML
    > >> > > > > > > > and
    > >> > > 
    > >> > > other
    > >> > > 
    > >> > > > > > > files for
    > >> > > > > > > 
    > >> > > > > > > > this.
    > >> > > > > > > 
    > >> > > > > > > For sensors' config, please refer to
    > >> > > > > > > https://github.com/openbmc/docs/blob/master/sensor-architectu
    > >> > > > > > > re.md
    > >> > > > > > > 
    > >> > > > > > > And it looks you are looking for fan controls, then you could
    > >> > > 
    > >> > > refer
    > >> > > to:
    > >> > > 
    > >> > > https://github.com/mine260309/openbmc-intro/blob/master/Porting_Guide
    > >> > > .md#f
    > >> > > 
    > >> > > > > > > ans
    > >> > > > > > > 
    > >> > > > > > > (I really need to submit my porting guide to openbmc/docs)