[PATCH 1/2] boot: android: Always use 8-byte aligned DT with libfdt

[Simon Glass]

Hi Marek,

On Thu, 13 Nov 2025 at 14:57, Marek Vasut <marek.vasut at mailbox.org> wrote:
>
> On 11/13/25 9:36 PM, Tom Rini wrote:
>
> Hello everyone,
>
> >>> Which is different from disagreeing with your specific feedback about
> >>> how we get there, to be clear.
> >
> > And again, since your feedback to this patch was "Don't?", I'm saying we
> > need to. But the rest of your feedback was structural on moving towards
> > resolving it and so I assume Marek will respond.
>
> The "blast radius" are these patches, that's all that tripped the tests:
>
>   - boot: android: Always use 8-byte aligned DT with libfdt
>   - test/py: android: Point fdt command to aligned addresses
>   - test/py: Use aligned address for overlays in 'extension' test
>   - sandbox: Fix DT compiler address warnings in sandbox DTs
>   - sandbox: Fix DT compiler pin warnings in sandbox DTs
>   - boot: Assure FDT is always at 8-byte aligned address
>   - arm: qemu: Eliminate fdt_high and initrd_high misuse
>   - efi_loader: Assure fitImage from capsule is used from 8-byte aligned
> address
>   - MIPS: Assure end of U-Boot is at 8-byte aligned offset
>
> Regarding last minute alignment, the problem with this android image
> seems to be in the android image itself, which packs in badly aligned
> FDT. We therefore have to copy it out and realign.

My request is to implement these checks as part of the boot flow
(bootm, etc.) rather than adding memory allocations in leaf function.
We already support copying the FDT to a different address so we can
expand it and add things. Can we make use of that code?

Regards,
SImon