Re: [PATCH v2 00/21] FWU: Migrate FWU metadata to version 2

[Etienne CARRIERE - foss <etienne.carriere@foss.st.com>]

Hello Sughosh,

Sorry for this very late reply especially since I have a quite negative feedback  on the proposed changes.

I don't think FWU metadata version 1 should be removed from U-Boot support.
There are existing immutable boot agent relying on format v1, starting from the Synquacer boards based on SCP-firmware v2.11 [1] onward (at least up to latest v2.13 tag) and the stm32mp1 platforms based on TF-A v2.7 [2] onward (at least up to latest tag v2.10). These platforms should be able to update there EFI firmware hence needing the update agent (U-Boot) to support format v1.

With the proposed series, the new format v2 contains the same information the previous mdata v1 based implementation did (apart that some info where built-in whereas v2 describe them from the mdata storage area).
Could it be possible the implementation support both, using for example a internal structure fed from either format v1 or v2 content read from the storage, and used to update the mdata  v1 or v2 format storage layout?

[1] https://gitlab.arm.com/firmware/SCP-firmware/-/blob/v2.11.0/product/synquacer/include/fwu_mdata.h
[2] https://review.trustedfirmware.org/plugins/gitiles/TF-A/trusted-firmware-a/+/refs/tags/v2.7/include/drivers/fwu/fwu_metadata.h

Best regards,
Etienne

> From: Sughosh Ganu <sughosh.ganu@linaro.org>
> 
> The following patches migrate the FWU metadata access code to version
> 2 of the structure. This is based on the structure definition as
> defined in the latest rev of the FWU Multi Bank Update specification
> [1].
> 
> Since the version 1 of the structure has currently been adopted on a
> couple of platforms, it was decided to have a clean migration of the
> metadata to version 2 only, instead of supporting both the versions of
> the structure. Also, based on consultations with the main author of
> the specification, it is expected that any further changes in the
> structure would be minor tweaks, and not be significant. Hence a
> migration to version 2.
> 
> Similar migration is also being done in TF-A, including migrating the
> ST platform port to support version 2 of the metadata structure [2].
> 
> @Michal, I tested the metadata for the two image per bank case, and it
> works fine on the ST board. Kindly test this on your board as well.
> 
> @Kojima-san, Please help in testing the version 2 on your
> board. Thanks.
> 
> 
> [1] - https://developer.arm.com/documentation/den0118/latest/
> [2] - https://review.trustedfirmware.org/q/topic:%22topics/fwu_metadata_v2_migration%22
> 
> Changes since V1:
> 
> * Do not define flexible array members inside the structures.
> * Access the image information related fields in the metadata using
>   the helper functions defined in an earlier patch.
> * Access fwu_fw_store_desc structure using pointer arithmetic.
> 
> (snip)