eBMC LED Management :: LampTest :: PLDM message to PHYP to start LampTest

[vishwabmc]

As part of Lamp Test, we need to send a command to PHYP and thus need to send a PLDM command. The details would be pretty much like how a soft off did SetHostStateEffector. I am working with PHYP team so that they define an effector that BMC can use.

The change needs to go into the phosphor-led-manager and needs to be part of a lamp-test process. That is, in addition to sending commands to physical LEDs, the led-manager needs to make this PLDM call.

[vishwabmc]

There is a change in the design on this.. The change is that we will use xyz/openbmc_project/led/groups/lamp_test group and its Asserted property. As a by product of this, a PropertyChangedSignal gets emitted and that will be caught by PLDM daemon and hence would send a command to PHYP.
Keeping it open until we are closed on that.

[vishwabmc]

We are still committed to using Asserted property. However, instead of leaning onto PLDM daemon, the best is to have this code send the SetHostStateEffector since it's entirely driven by LED Manager Lamp-Test

At this moment, we don't have the HostEffector defined . but we can get going with rest of BMC implementation.
This code needs to be called whenever Asserted property is set to true.. Nothing needs to be done as part of Asserted being set to false

[vishwabmc]

From discussion with PHYP, here is the proposal:

---

• Step 1: PHYP presents an entity for Lamp Test with ONE effecter (see below):
  Logical Entity Type = 19 - Indicator

• Step 2: BMC sets a PHYP-provided Numeric Effecter to set the lamp test duration:
  https://www.dmtf.org/sites/default/files/standards/documents/DSP0248_1.2.0.pdf#%5B%7B%22num%22%3A348%2C%22gen%22[…]%3A%22XYZ%22%7D%2C69%2C237%2C0%5D

• Units on Numeric Effecter will be time-based (seconds, probably?). So baseUnit == 21

• When PHYP receives a non-zero value on this effecter, it will run the lamp test for this many seconds.

• There is no state effecter.

So, BMC will only set this HostEffector with "4 minutes" or whatever that is configured. There is nothing to be done as part of stopping lamp test.

[lxwinspur]

@vishwabmc
We get the effecter ID by the FindStateEffecterPDR interface,
https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/xyz/openbmc_project/PLDM/PDR.interface.yaml#L18
Now, we only know the EntityID value and not the StateSetId value.
Since both are the values are hard-code, Could you ask PHYP team and what the StateSetID value is?

[vishwabmc]

https://gerrit.openbmc-project.xyz/c/openbmc/meta-phosphor/+/39963 : it was discussed in this and we have a new direction.

• PLDM daemon would host a new interface that LED manager will call into
• the new interface abstracts everything. The API will be like LampTest(time-out-in-milli-secs)
• LED manager just makes that call.

@sampmisr FYA ^

[vishwabmc]

https://gerrit.openbmc-project.xyz/c/openbmc/meta-phosphor/+/39963 : it was discussed in this and we have a new direction.

* PLDM daemon would host a new interface that LED manager will call into

* the new interface abstracts everything. The API will be like `LampTest(time-out-in-milli-secs)`

* LED manager just makes that call.

@sampmisr FYA ^

Okay.. finally, we have full clarity :)

• PLDM daemon will implement xyz.openbmc_project.Led.Group interface
• PLDM will host /xyz/openbmc_project/led/groups/host_lamp_test D-Bus object
• LED manager will set asserted property to true on the above object
• PLDM daemon will do SetHostStateEffector when the property is true
• When the LampTest times out, LED manager sets the property to false
• PLDM will not do anything when it is false as PHYP will auto stop the timer

@sampmisr @lxwinspur ^

[lxwinspur]

@vishwabmc @sampmisr
Okay, Pls let me do all of the above (LED manager and PLDM daemon). :)

[lxwinspur]

reveiw by: https://gerrit.openbmc-project.xyz/c/openbmc/phosphor-led-manager/+/39958

[vishwabmc]

PLDM review at : https://gerrit.openbmc-project.xyz/c/openbmc/pldm/+/40373

[gtmills]

@lxwinspur Can we try to get https://gerrit.openbmc-project.xyz/c/openbmc/pldm/+/40373 in?

[lxwinspur]

Sure, will update

[lxwinspur]

@gtmills @manojkiraneda

Updated, Please review this patch.
https://gerrit.openbmc-project.xyz/c/openbmc/pldm/+/40373

[lxwinspur]

@mzipse @manojkiraneda
https://gerrit.openbmc.org/c/openbmc/pldm/+/40373
This patch Merge Conflict again. Does IBM have any plans to review this patch?