tree 3fdfa408814e4067b4f8ff969b7a5d03f2fb0d17
parent 8f05a3a18b288c6a8897c4b42facc98db156c2e1
author Sui Chen <suichen@google.com> 1663089723 -0700
committer Zhikui Ren <zhikui.ren@intel.com> 1671590060 +0000

entity-manager: Allow exposing BMC inventory with "ContainsThisBMC"

Recently there appeared use cases involving the usage of a BMC Inventory
item. One example is the utilization sensors in phosphor-health-monitor;
those sensors need to be connected to the BMC inventory item via an
association edge so they can be found by bmcweb.

Based on the conventions of OpenBMC, when a daemon owns a BMC Inventory
item, it is expected to have a complete understanding of the underlying
object. As such, Entity-Manager is in a better position to own the BMC
Inventory item compared to any other daemon.

Customarily, an Inventory item must always refer to a tangible, physical
object such as a board. The BMC Inventory item Inventory item is an
exception, since in most cases a BMC is not a discrete physical object
and is usually embedded into another physical component, such as a
DC-SCM module or a Board. A such, the information regarding a BMC must
be encoded in the board's JSON file, rather than a JSON file of its own.

This change makes entity-manager add an Inventory.Item.Bmc upon seeing
an "Exposed" entry with "BMC" type.

Tested: After adding 'HasThisBMC: true' to a board .JSON file, the BMC
item shows up:

bmc# busctl tree xyz.openbmc_project.EntityManager
`-/xyz
  `-/xyz/openbmc_project
    |-/xyz/openbmc_project/EntityManager
    `-/xyz/openbmc_project/inventory
      `-/xyz/openbmc_project/inventory/system
        |-/xyz/openbmc_project/inventory/system/board
        | `-/xyz/openbmc_project/inventory/system/board/SuperBoard
        |   `-/xyz/openbmc_project/inventory/system/board/SuperBoard/BMC

Signed-off-by: Sui Chen <suichen@google.com>
Change-Id: Iaf3595d4c336dbcf1f4e42f4aaa2c6c1840f9584