sensor->inventory associations in phosphor-hwmon

sensor->inventory associations in phosphor-hwmon

[Matt Spinler]

Hi,

We have a need to know which sensor objects hosted by the various 
phosphor-hwmon
daemons belong to which inventory objects.  For example, we need to know 
that
the /xyz/openbmc_project/sensors/power/ps1_input_power sensor belongs to 
the
/xyz/openbmc_project/inventory/system/powersupply1 item.

To accomplish this, I am proposing we add a new environment variable to 
the
system specific phosphor-hwmon config files that the phosphor-hwmon code
can then use to create associations interfaces that will cause the 
mapper to
create the appropriate association D-Bus paths.

As an example, we could add to the power-supply1 conf file an 
ASSOCIATIONS
variable for each sensor (assuming ps1_input_power is represented by 
IN1):

     ASSOCIATIONS_IN1=/xyz/openbmc_project/inventory/system/powersupply1

The code would then see that and create a new org.openbmc.Associations 
interface
on the /xyz/openbmc_project/sensors/power/ps1_input_power path with an
associations property of:

     ["inventory",
      "sensors",
      "/xyz/openbmc_project/inventory/system/powersupply1"]

This leads to the mapper creating:

     /xyz/openbmc_project/sensors/power/ps1_input_power/inventory

With an xyz.openbmc_project.Association interface with an
endpoints property of:

     ["/xyz/openbmc_project/inventory/system/powersupply1"]

And also the other association path:

     /xyz/openbmc_project/inventory/system/powersupply1/sensors

With an xyz.openbmc_project.Association interface with an
endpoints property of:

     ["/xyz/openbmc_project/sensors/power/ps1_input_power"]

This now allows one to both find all sensors associated with a power 
supply, and
find which inventory item is associated with a particular sensor.  Note 
that
the endpoints property is an array, and can get entries from multiple 
places.

I suppose we could also put the forward/reverse association names, in 
this case
"inventory" and "sensors", into the hwmon config file, and also allow 
creating
multiple associations for each sensor if there is a usecase, though I 
would like
to keep it as simple as possible:

ASSOCIATIONS1_IN1=inventory,sensors,/xyz/openbmc_project/inventory/system/powersupply1
ASSOCIATIONS2_IN1=chassis,contained_sensors,/xyz/openbmc_project/inventory/system/chassis

What does everyone think?

Thanks
Matt

sensor->inventory associations in phosphor-hwmon

[Matt Spinler]

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Hi,

We have a need to know which sensor objects hosted by the various phosphor-hwmon
daemons belong to which inventory objects.  For example, we need to know that
the /xyz/openbmc_project/sensors/power/ps1_input_power sensor belongs to the
/xyz/openbmc_project/inventory/system/powersupply1 item.

To accomplish this, I am proposing we add a new environment variable to the
system specific phosphor-hwmon config files that the phosphor-hwmon code
can then use to create associations interfaces that will cause the mapper to
create the appropriate association D-Bus paths.

As an example, we could add to the power-supply1 conf file an ASSOCIATIONS
variable for each sensor (assuming ps1_input_power is represented by IN1):

     ASSOCIATIONS_IN1=/xyz/openbmc_project/inventory/system/powersupply1

The code would then see that and create a new org.openbmc.Associations interface
on the /xyz/openbmc_project/sensors/power/ps1_input_power path with an
associations property of:

     ["inventory",
      "sensors",
      "/xyz/openbmc_project/inventory/system/powersupply1"]

This leads to the mapper creating:

     /xyz/openbmc_project/sensors/power/ps1_input_power/inventory

With an xyz.openbmc_project.Association interface with an
endpoints property of:

     ["/xyz/openbmc_project/inventory/system/powersupply1"]

And also the other association path:

     /xyz/openbmc_project/inventory/system/powersupply1/sensors

With an xyz.openbmc_project.Association interface with an
endpoints property of:

     ["/xyz/openbmc_project/sensors/power/ps1_input_power"]

This now allows one to both find all sensors associated with a power supply, and
find which inventory item is associated with a particular sensor.  Note that
the endpoints property is an array, and can get entries from multiple places.

I suppose we could also put the forward/reverse association names, in this case
"inventory" and "sensors", into the hwmon config file, and also allow creating
multiple associations for each sensor if there is a usecase, though I would like
to keep it as simple as possible:

ASSOCIATIONS1_IN1=inventory,sensors,/xyz/openbmc_project/inventory/system/powersupply1
ASSOCIATIONS2_IN1=chassis,contained_sensors,/xyz/openbmc_project/inventory/system/chassis

What does everyone think?

Thanks
Matt


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Re: sensor->inventory associations in phosphor-hwmon

[Patrick Venture]

On Wed, Feb 20, 2019 at 10:31 AM Matt Spinler <mspinler@linux.ibm.com> wrote:
>
> Hi,
>
> We have a need to know which sensor objects hosted by the various
> phosphor-hwmon
> daemons belong to which inventory objects.  For example, we need to know
> that
> the /xyz/openbmc_project/sensors/power/ps1_input_power sensor belongs to
> the
> /xyz/openbmc_project/inventory/system/powersupply1 item.
>
> To accomplish this, I am proposing we add a new environment variable to
> the
> system specific phosphor-hwmon config files that the phosphor-hwmon code
> can then use to create associations interfaces that will cause the
> mapper to
> create the appropriate association D-Bus paths.
>
> As an example, we could add to the power-supply1 conf file an
> ASSOCIATIONS
> variable for each sensor (assuming ps1_input_power is represented by
> IN1):
>
>      ASSOCIATIONS_IN1=/xyz/openbmc_project/inventory/system/powersupply1
>
> The code would then see that and create a new org.openbmc.Associations
> interface
> on the /xyz/openbmc_project/sensors/power/ps1_input_power path with an
> associations property of:
>
>      ["inventory",
>       "sensors",
>       "/xyz/openbmc_project/inventory/system/powersupply1"]
>
> This leads to the mapper creating:
>
>      /xyz/openbmc_project/sensors/power/ps1_input_power/inventory
>
> With an xyz.openbmc_project.Association interface with an
> endpoints property of:
>
>      ["/xyz/openbmc_project/inventory/system/powersupply1"]
>
> And also the other association path:
>
>      /xyz/openbmc_project/inventory/system/powersupply1/sensors
>
> With an xyz.openbmc_project.Association interface with an
> endpoints property of:
>
>      ["/xyz/openbmc_project/sensors/power/ps1_input_power"]
>
> This now allows one to both find all sensors associated with a power
> supply, and
> find which inventory item is associated with a particular sensor.  Note
> that
> the endpoints property is an array, and can get entries from multiple
> places.
>
> I suppose we could also put the forward/reverse association names, in
> this case
> "inventory" and "sensors", into the hwmon config file, and also allow
> creating
> multiple associations for each sensor if there is a usecase, though I
> would like
> to keep it as simple as possible:
>
> ASSOCIATIONS1_IN1=inventory,sensors,/xyz/openbmc_project/inventory/system/powersupply1
> ASSOCIATIONS2_IN1=chassis,contained_sensors,/xyz/openbmc_project/inventory/system/chassis
>
> What does everyone think?

I think it's useful and straightforward to use, and easy to test.

>
> Thanks
> Matt
>

Re: sensor->inventory associations in phosphor-hwmon

[James Feist]

On 2/20/19 10:32 AM, Patrick Venture wrote:
> On Wed, Feb 20, 2019 at 10:31 AM Matt Spinler <mspinler@linux.ibm.com> wrote:
>>
>> Hi,
>>
>> We have a need to know which sensor objects hosted by the various
>> phosphor-hwmon
>> daemons belong to which inventory objects.  For example, we need to know
>> that
>> the /xyz/openbmc_project/sensors/power/ps1_input_power sensor belongs to
>> the
>> /xyz/openbmc_project/inventory/system/powersupply1 item.
>>
>> To accomplish this, I am proposing we add a new environment variable to
>> the
>> system specific phosphor-hwmon config files that the phosphor-hwmon code
>> can then use to create associations interfaces that will cause the
>> mapper to
>> create the appropriate association D-Bus paths.
>>
>> As an example, we could add to the power-supply1 conf file an
>> ASSOCIATIONS
>> variable for each sensor (assuming ps1_input_power is represented by
>> IN1):
>>
>>       ASSOCIATIONS_IN1=/xyz/openbmc_project/inventory/system/powersupply1
>>
>> The code would then see that and create a new org.openbmc.Associations
>> interface
>> on the /xyz/openbmc_project/sensors/power/ps1_input_power path with an
>> associations property of:
>>
>>       ["inventory",
>>        "sensors",
>>        "/xyz/openbmc_project/inventory/system/powersupply1"]
>>
>> This leads to the mapper creating:
>>
>>       /xyz/openbmc_project/sensors/power/ps1_input_power/inventory
>>
>> With an xyz.openbmc_project.Association interface with an
>> endpoints property of:
>>
>>       ["/xyz/openbmc_project/inventory/system/powersupply1"]
>>
>> And also the other association path:
>>
>>       /xyz/openbmc_project/inventory/system/powersupply1/sensors
>>
>> With an xyz.openbmc_project.Association interface with an
>> endpoints property of:
>>
>>       ["/xyz/openbmc_project/sensors/power/ps1_input_power"]
>>
>> This now allows one to both find all sensors associated with a power
>> supply, and
>> find which inventory item is associated with a particular sensor.  Note
>> that
>> the endpoints property is an array, and can get entries from multiple
>> places.
>>
>> I suppose we could also put the forward/reverse association names, in
>> this case
>> "inventory" and "sensors", into the hwmon config file, and also allow
>> creating
>> multiple associations for each sensor if there is a usecase, though I
>> would like
>> to keep it as simple as possible:
>>
>> ASSOCIATIONS1_IN1=inventory,sensors,/xyz/openbmc_project/inventory/system/powersupply1
>> ASSOCIATIONS2_IN1=chassis,contained_sensors,/xyz/openbmc_project/inventory/system/chassis
>>
>> What does everyone think?
> 
> I think it's useful and straightforward to use, and easy to test.

Have we considered the alternative of the inventory item creating the 
association? I only ask because in the past we've tried to keep 
redfish/ipmi specific things outside of the sensors. I think this 
proposal works fine btw, just seems like the alternative would work as 
well and would keep sensors as just 'sensors'.

-James

> 
>>
>> Thanks
>> Matt
>>

Re: sensor->inventory associations in phosphor-hwmon

[Matt Spinler]

On 2/20/2019 12:47 PM, James Feist wrote:
> On 2/20/19 10:32 AM, Patrick Venture wrote:
>> On Wed, Feb 20, 2019 at 10:31 AM Matt Spinler 
>> <mspinler@linux.ibm.com> wrote:
>>>
>>> Hi,
>>>
>>> We have a need to know which sensor objects hosted by the various
>>> phosphor-hwmon
>>> daemons belong to which inventory objects.  For example, we need to 
>>> know
>>> that
>>> the /xyz/openbmc_project/sensors/power/ps1_input_power sensor 
>>> belongs to
>>> the
>>> /xyz/openbmc_project/inventory/system/powersupply1 item.
>>>
>>> To accomplish this, I am proposing we add a new environment variable to
>>> the
>>> system specific phosphor-hwmon config files that the phosphor-hwmon 
>>> code
>>> can then use to create associations interfaces that will cause the
>>> mapper to
>>> create the appropriate association D-Bus paths.
>>>
>>> As an example, we could add to the power-supply1 conf file an
>>> ASSOCIATIONS
>>> variable for each sensor (assuming ps1_input_power is represented by
>>> IN1):
>>>
>>> ASSOCIATIONS_IN1=/xyz/openbmc_project/inventory/system/powersupply1
>>>
>>> The code would then see that and create a new org.openbmc.Associations
>>> interface
>>> on the /xyz/openbmc_project/sensors/power/ps1_input_power path with an
>>> associations property of:
>>>
>>>       ["inventory",
>>>        "sensors",
>>>        "/xyz/openbmc_project/inventory/system/powersupply1"]
>>>
>>> This leads to the mapper creating:
>>>
>>> /xyz/openbmc_project/sensors/power/ps1_input_power/inventory
>>>
>>> With an xyz.openbmc_project.Association interface with an
>>> endpoints property of:
>>>
>>>       ["/xyz/openbmc_project/inventory/system/powersupply1"]
>>>
>>> And also the other association path:
>>>
>>> /xyz/openbmc_project/inventory/system/powersupply1/sensors
>>>
>>> With an xyz.openbmc_project.Association interface with an
>>> endpoints property of:
>>>
>>>       ["/xyz/openbmc_project/sensors/power/ps1_input_power"]
>>>
>>> This now allows one to both find all sensors associated with a power
>>> supply, and
>>> find which inventory item is associated with a particular sensor.  Note
>>> that
>>> the endpoints property is an array, and can get entries from multiple
>>> places.
>>>
>>> I suppose we could also put the forward/reverse association names, in
>>> this case
>>> "inventory" and "sensors", into the hwmon config file, and also allow
>>> creating
>>> multiple associations for each sensor if there is a usecase, though I
>>> would like
>>> to keep it as simple as possible:
>>>
>>> ASSOCIATIONS1_IN1=inventory,sensors,/xyz/openbmc_project/inventory/system/powersupply1 
>>>
>>> ASSOCIATIONS2_IN1=chassis,contained_sensors,/xyz/openbmc_project/inventory/system/chassis 
>>>
>>>
>>> What does everyone think?
>>
>> I think it's useful and straightforward to use, and easy to test.
>
> Have we considered the alternative of the inventory item creating the 
> association? I only ask because in the past we've tried to keep 
> redfish/ipmi specific things outside of the sensors. I think this 
> proposal works fine btw, just seems like the alternative would work as 
> well and would keep sensors as just 'sensors'.
>

After our discussion on IRC, I will look into adding the functionality 
in phosphor-inventory-manager to add any required inventory 
associations, which would cover LEDs, sensors, etc, and then you can do 
the same for Entity-Manager.  That way, the bmcweb Redfish code that 
would use these can be common.


> -James
>
>>
>>>
>>> Thanks
>>> Matt
>>>
>