xref: /openbmc/docs/designs/boot-progress.md (revision 37055f7d)
1# System Boot Progress on OpenBMC
2
3Author: Andrew Geissler (geissonator)
4
5Other contributors: None
6
7Created: May 27, 2020
8
9## Problem Description
10The boot progress of an OpenBMC managed system is complex. There are a mix
11of phosphor D-Bus properties, IPMI sensors, PLDM sensors, and Redfish
12properties to represent it. The goal of this design document is to highlight
13these different entities and provide a base for system implementors on what
14to implement.
15
16## Background and References
17[phosphor-state-manager][1] implements D-Bus properties which track the state
18of the BMC, Chassis, and Host. This design is primarily focused on the status
19of the Host since it is the most complex. Specifically the goal is to provide
20detailed information on what the host is doing during a boot.
21
22[HostState][2] provides basic `Off`/`Running` type information along
23with an error state (`Quiesced`) and debug state (`DiagnosticMode`). The focus
24of this document is the `Running` state. This simply indicates whether something
25is running on the host processors.
26
27phosphor-state-manager implements some other D-Bus properties that represent
28the host boot progress:
29
30- [xyz.openbmc_project.State.Boot.Progress][3]
31- [xyz.openbmc_project.State.OperatingSystem.Status][4]
32
33These two D-Bus properties are very IPMI-centric. They were defined based on
34two IPMI sensors which are set by the host firmware as it boots the system.
35
36PLDM also has a boot progress sensor. Search for "Boot Progress" in this
37[doc][5]. A subset of this maps fairly well to the IPMI sensors above. This
38PLDM sensor is not implemented yet in OpenBMC code.
39
40Redfish represents system state in a variety of ways. The BMC, Chassis,
41and System all implement a [Status][6] object. This provides a list of generic
42`State` options which are applicable to Redfish objects. OpenBMC has the
43following mapping for phosphor-state-manager to the Redfish System
44[Status][State]:
45- `xyz.openbmc_project.State.Host.HostState.Running` : `Enabled`
46- `xyz.openbmc_project.State.Host.HostState.Quiesced` : `Quiesced`
47- `xyz.openbmc_project.State.Host.HostState.DiagnosticMode` : `InTest`
48
49As of [ComputerSystem.v1_13_0][7], the `BootProgress` object is officially in
50the Redfish ComputerSystem schema.
51
52To summarize, the `LastState` property under this new `BootProgress` object
53tracks the following boot states of the system:
54
55- None
56- PrimaryProcessorInitializationStarted
57- BusInitializationStarted
58- MemoryInitializationStarted
59- SecondaryProcessorInitializationStarted
60- PCIResourceConfigStarted
61- SystemHardwareInitializationComplete
62- OSBootStarted
63- OSRunning
64- OEM
65
66There is also a `LastStateTime` associated with this new BootProgress object
67which should be updated with the date and time the `LastState` was last
68updated.
69
70In the end, the goal is to be able to map either the IPMI or PLDM boot sensors
71into all or some of the values in this new Redfish property.
72
73Note that this design does not include multi-host computer system concepts but
74it also does not preclude them. The `BootProgress` D-Bus property is associated
75with a `/xyz/openbmc_project/state/host<X>` instance where <X> is the host
76instance. Similarly, the Redfish system object is also an instance based
77object.
78
79## Requirements
80- Enhance the existing [BootProgress][3] D-Bus property to cover all supported
81  PLDM boot progress codes
82- Create a new `BootProgressLastUpdate` D-Bus property that will hold the
83  date and time of the last update to `BootProgress`
84- Ensure the `BootProgress` and `BootProgressLastUpdate` properties are updated
85  appropriately in both IPMI and PLDM based stacks
86  - It is the responsibility of the IPMI or PLDM implementation to update
87    the `BootProgress` property on D-Bus
88  - It is the responsibility the phosphor-state-manager to update the
89    `BootProgressLastUpdate` property on D-Bus when it sees `BootProgress`
90    updated
91- Ensure the new Redfish `LastState` and `LastStateTime` properties
92  have the appropriate mappings to the `BootProgress` and
93  `BootProgressLastUpdate D-Bus properties
94
95Different OpenBMC systems could support different boot progress codes, and
96support them in different orders. This document does not try to set any
97requirements on this other than that they must all be defined within
98the `BootProgress` D-Bus property and the ones which have a mapping
99to the Redfish BootProgress object will be shown via the Redfish interface.
100
101## Proposed Design
102[BootProgress][3] will be enhanced to support a superset of what is provided
103by IPMI and PLDM.
104
105IPMI code already sets the `BootProgress` D-Bus property based on a config
106file. Look for `fw_boot_sensor` in this [file][8] for an example of how a
107particular IPMI sensor is mapped to this D-Bus property.
108
109PLDM software will do something similar.
110
111bmcweb will then use this `BootProgress` D-Bus interface to respond
112appropriately to Redfish requests.
113
114## Alternatives Considered
115A lot of system BIOS's provided some form of a detailed boot progress codes.
116UEFI has POST codes, POWER has istep progress codes. If more fine grained
117details were needed, we could look into using these. Currently though the
118need is just high level boot progress. Note that these POST/istep codes
119could be mapped to the appropriate BootProgress value if desired (or for
120cases where the host does not support an IPMI or PLDM stack that has
121BootProgress in it).
122
123## Impacts
124Each system will need to document which `BootProgress` codes they support
125and the expected order of them when a system is booting.
126
127## Testing
128Ensure an IPMI and PLDM based system boot and update the `BootProgress` D-Bus
129property as expected.
130
131
132[1]: https://github.com/openbmc/phosphor-state-manager#state-tracking-and-control
133[2]: https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/yaml/xyz/openbmc_project/State/Host.interface.yaml
134[3]: https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/yaml/xyz/openbmc_project/State/Boot/Progress.interface.yaml
135[4]: https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/yaml/xyz/openbmc_project/State/OperatingSystem/Status.interface.yaml
136[5]: https://www.dmtf.org/sites/default/files/standards/documents/DSP0249_1.0.0.pdf
137[6]: http://redfish.dmtf.org/schemas/v1/Resource.json#/definitions/Status
138[7]: https://redfish.dmtf.org/schemas/v1/ComputerSystem.v1_13_0.json
139[8]: https://github.com/openbmc/meta-ibm/blob/master/recipes-phosphor/configuration/acx22-yaml-config/acx22-ipmi-sensors-mrw.yaml
140