docs/designs/psu-firmware-update.md

1 # PSU firmware update
11 There is no support in OpenBMC to update the firmware for PSUs.
15 In OpenBMC, there is an existing interface for [software update][1].
17 The update process consists of:
23 Currently, BMC and BIOS firmware update are supported:
25 - [phosphor-bmc-code-mgmt][2] implements BMC code update, and it supports all
27 - [openpower-pnor-code-mgmt][3] implements BIOS code update, and it only
32 For PSU firmware update, it is preferred to re-use the same function for the
39 1. The user manually invokes the APIs to do the update;
40 2. After BMC code update and if there is a newer PSU image in the BMC's
41    filesystem, BMC shall update the PSU firmware;
43    filesystem, BMC shall update the PSU firmware.
44 4. An optional 'override' parameter may be specified to do the update in the
49 For some PSUs, it is risky to do PSU code update while the host is running to
68 - When a new version is updated together with BMC code update;
71 ### Update by API
73 This method is usually used by users who manually update PSU firmware.
83    - The PSU update image shall be a tarball that consists of a MANIFEST,
88    update the PSU firmware.
101      update. For example, if a vendor specific tool `foo` is configured in
102      `psu-update@foo.service` which executes `foo psu.bin`, the service will
103      find the `psu-update@foo.service` and start it by systemd, which performs
104      the update.
105    - When the PSU code update is completed, an informational event log shall be
107    - When the PSU code update is completed, the image, MANIFEST, and optionally
111    and after the PSU update, and return a status to the above service to
113 5. When the vendor-specific tool returns errors, the PSU update will be aborted
115 6. During the update, the service shall set the related sensors to
116    non-functional, and when the update is done, it shall set the related sensors
119 ### Update by new BMC image
126    update shall be performed.
131      location for the saved PSU images by API update. Both places shall be
134 3. If PSU update is needed, the service will find the matched vendor-specific
135    tool to perform the code update.
136 4. The following process will be the same as [Update by API].
138 ### Update on replaced PSU
151    code update.
152 4. The following process will be the same as [Update by API].
158 The PSU firmware update could be implemented by separated recipes that only call
160 provided by OpenBMC's existing [software update interface][1], and thus it will
161 become difficult to use a standard API to the PSU firmware update.
185 interfaces. The newly introduced PSU firmware update service will be a new
197 It requires the manual tests to verify the PSU code update process.
199 - Verify the PSU code update is done on all PSUs successfully;
200 - Verify the PSU code update will fail if the vendor-specific tool fails on
202 - Verify the PSU code update is performed after a new BMC image is updated
204 - Verify the PSU code update is performed after a PSU with old (or different, if