[PATCH 0/6] Add support for fwumdata

[Ilias Apalodimas]

Hi Patryk,

On Wed, 3 Dec 2025 at 16:04, Patryk <pbiel7 at gmail.com> wrote:
>
> Hi Ilias,
>
> > > > Add a new fwumdata tool to allows users to read, display, and modify FWU
> > > > (Firmware Update) metadata from Linux userspace. It provides functionality
> > > > similar to fw_printenv/fw_setenv but for FWU metadata. Users can view
> > > > metadata, change active/previous bank indices, modify bank states, and set
> > > > image acceptance flags. Configuration is done via fwumdata.config file.
> > > >
> > > > Made a few change to mkfwumdata tool along the way.
> > >
> > > Still wondering about the choice of putting this fwumdata tool in U-Boot
> > > instead of TF-A. TF-A is the boot part that manages the update process and
> > > rollback through the FWU metadata,
> > > therefore, this is where it should belong.
> > > Why, in the first place, mkfwumdata was accepted into U-boot instead of TF-A?
> >
> > The actual update happens via capsule updates only, which runs in
> > BL33. TF-A needs to be aware in case it's involved in the boot process
> > and fails to boot. In that case BL2 is responsible for booting via the
> > other bank.
> > But generally speaking it's U-Boot that processes and usually updates that file
>
> If I may add something - actually for me this is not that obvious,
> e.g. on our platform we update the metadata directly from Linux, not
> from the u-boot capsule. As far as I'm aware, the ST, in their
> OpenstLinux does the same.
> I'm also not sure why it would be the bad
> idea to do this from Linux. Ofc the BL2 handles bank selection as well
> as rollback in case of boot failure on a newly selected bank.
>

The whole point of the spec, is to be able to have A/B support via EFI
interfaces. There's also an indication in the ESRT table, that an
update is pending for approval.
But if the data lives in a file in the non-secure world you can
technically update it from linux.

Thanks
/Ilias
> Best regards
> Patryk