phosphor-power-sequencer/docs/chassis_status.md

1 # Chassis Status
5 There are multiple D-Bus interfaces and properties that describe the chassis
16 the chassis. 0 means off, and 1 means on. This property is set when the system
20 of the chassis. 0 means off, and 1 means on. This is the actual, current power
21 state. This property is set based on the chassis power good signal from the
28 - `/org/openbmc/control/power1`: Represents chassis 1
29 - `/org/openbmc/control/power2`: Represents chassis 2
31 - `/org/openbmc/control/powerN`: Represents chassis N
33 ### Single chassis system
35 On a single chassis system, only the first two object paths are published,
36 representing the entire system and chassis 1. The values of the `state` and
43 is set to 1. When the chassis has successfully powered on, the `pgood` property
47 is set to 0. When the chassis has successfully powered off, the `pgood` property
50 ### Multiple chassis system
52 On a multiple chassis system with N chassis, all of the object paths above are
54 the other object paths represent the state of the individual chassis.
60 system and for all chassis that **can** be powered on. It may not be possible to
61 power on some chassis, such as if they are missing or have no input power. See
64 When an individual chassis has successfully powered on, the `pgood` property for
65 that object path will change to 1. When all chassis whose `state` was set to 1
69 If a power good fault occurs in a chassis after the system powered on, the
70 `pgood` property for that chassis's object path will change to 0. The `pgood`
76 system and for all chassis that are being powered off.
78 When an individual chassis has successfully powered off, the `pgood` property
79 for that object path will change to 0. When all chassis have successfully
88 The chassis power good signal is read from the power sequencer device. Both the
90 For example, if the chassis power good is true, both `state` and `pgood` are set
91 to the value 1. Thus, `phosphor-power-sequencer` assumes the chassis `state`
92 based on the chassis `pgood`.
94 In a multiple chassis system, it might not be possible to read the chassis power
95 good signal. For example, the chassis might not be present or might have no
104 This interface is published on the D-Bus inventory path for each chassis.
106 `Present` property on multiple chassis systems.
108 The `Present` property indicates whether a chassis is physically present.
110 If `Present` is set to false for a chassis:
112 - The chassis power good signal from the power sequencer will **not** be read.
113   Since the chassis is not present, the `pgood` property on the
114   `org.openbmc.control.Power` interface for the chassis will be set to 0.
115 - The chassis will **not** be powered on when the system is being powered on.
117   chassis will remain set to 0.
124 This interface is published on the D-Bus inventory path for each chassis.
126 `Available` property on multiple chassis systems.
129 false, it means that communication to the chassis is not possible. For example,
130 the chassis does not have any input power ([blackout](power_loss.md)) or
133 If `Available` is set to false for a chassis:
135 - The chassis power good signal from the power sequencer will **not** be read.
136   Since communication to the chassis is not possible, the value of the power
138   - If the chassis is experiencing a blackout, the chassis has no input power
140   - If all other chassis have a `pgood` value of 0, the `pgood` value will be
141     set to 0 for this chassis.
142   - If at least one other chassis has a `pgood` value of 1, the `pgood` value
143     will be set to 1 for this chassis.
144 - The chassis will **not** be powered on when the system is being powered on.
146   chassis will remain set to 0.
153 This interface is published on the D-Bus inventory path for each chassis.
155 `Enabled` property on multiple chassis systems.
158 false, it means that the chassis has been put in hardware isolation (guarded). A
159 critical error has been detected in the chassis, and it will not be used when
162 If `Enabled` is set to false for a chassis:
164 - The chassis power good signal from the power sequencer will be read. The
165   `pgood` property on the `org.openbmc.control.Power` interface for the chassis
167 - The chassis will **not** be powered on when the system is being powered on.
169   chassis will remain set to 0.
177 `Status` property on multiple chassis systems.
180 `Fault`, it means that the chassis is experiencing a blackout or brownout. A
185 ### Chassis power status
187 The `phosphor-chassis-power` application publishes the
191 - `/xyz/openbmc_project/power/chassis/chassis1`
192 - `/xyz/openbmc_project/power/chassis/chassis2`
194 - `/xyz/openbmc_project/power/chassis/chassisN`
196 If `Status` is set to `Fault` for a chassis:
198 - The chassis is experiencing a blackout.
199 - The chassis power good signal from the power sequencer will **not** be read.
200   Since the chassis has no input power, the `pgood` property on the
201   `org.openbmc.control.Power` interface for the chassis will be set to 0.
202 - The chassis will **not** be powered on when the system is being powered on.
204   chassis will remain set to 0. An error will be logged indicating that the
205   chassis was not powered on due to an input power problem.
218 If `Status` is set to `Fault` for the PSUs in a chassis:
220 - The chassis is experiencing a brownout.
221 - The chassis power good signal from the power sequencer will be read. The
222   `pgood` property on the `org.openbmc.control.Power` interface for the chassis
224 - The chassis will **not** be powered on when the system is being powered on.
226   chassis will remain set to 0. An error will be logged indicating that the
227   chassis was not powered on due to an input power problem.