RFE for fwupd auto updates

[mangelajo]

Description

Recently I have been working on embedding firmware for custom peripherals or any peripheral in OS images.

This is especially useful for Edge systems, where some parts of the system could be peripherals (i.e., a radar, imaging device, sensors, controls, actuators) very specific to the system.

Having this capability, when the system image is updated (via OTA or any other means, USB stick, for example), the firmware for those peripherals is contained in the image.

In this type of environment, having fwupd update selected peripherals at boot would be useful. Even thinking further, in systems (like ostree based) that support A/B images, in this case via greenboot checks, it could be useful to let configuration mandate downgrades, for example:

scenario 1

a) System boots on version A, attached device y has firmware version 1.00, the system contains .cab for y in 1.00, fwupd boots normally nothing happens.

b) System reboots to version B, attached device y has firmware version 1.00, the system contains .cab for y 1.10, fwupd updates y to 1.10, then finishes booting. The application passes checks, greenboot declares all good. The system stays in B.

scenario 2, system update failure in A/B system

a) System boots on version A, attached device y has firmware version 1.00, the system contains .cab for y in 1.00, fwupd boots normally nothing happens.

b) System reboots to version B, attached device y has firmware version 1.00, the system contains .cab for y 1.10, fwupd updates y to 1.10, then finishes booting. The application fails, greenboot declares bad and tries to boot B again, but fails again.. System reboots to A.

c) System boots on version A, attached device y has firmware version 1.10, the system contains a .cab for y in 1.00, and configuration says downgrade for y is mandatory, fwupd downgrades y to 1.00 and finishes booting.

Proposal

Under those scenarios, a configuration similar to this is proposed:

under '/etc/fwupd/auto-updates.d/'

device-a.conf

[fwupd auto-update]
remote=Vendor (Automatic)
guid=5aea1200-2286-5819-93e6-3b5548b6c88a # USB\VID_0483&PID_DF11
update=true
downgrade=true # downgrade is enabled because the new firmware is protocol-incompatible across versions

device-b.conf

[fwupd auto-update]
remote=Vendor (Automatic)
guid=f7d494e1-3327-5c82-8227-fdb053fce37c # USB\VID_0483&PID_DF11
update=true

Notes

Upgrade or downgrade is always performed into the latest version available on the selected remote.

Keywords

• remote: allows specification of the remote to source the latest version available for a device, for example, if we want to avoid network sources to be effective for this purpose.
• guid (mandatory) specifies the GUID of the device being references
• update (defaults to true) enables the update for this device. An update is performed if the remote's latest version for the device GUID is > the device version.
• downgrade(defaults to false) enables the downgrade for this device if the remote latest version for the device GUID is < than the device version.

[hughsie]

I think you're asking for a "best known configuration". i.e. https://blogs.gnome.org/hughsie/2021/11/29/firmware-best-known-configuration-in-fwupd/ -- tell me if that might work.

[superm1]

That was exactly my thought too.

[mangelajo]

Tell me more! :D

[hughsie]

#5646 is a good start. Can you tell me what's still confusing or ambiguous?