Re: [PATCH 0/2] Add support for Gunyah Watchdog

[Alexander Koskovich]

Hey Konrad,

My device's EDK2 should be on 'KERNEL.PLATFORM.3.0.r1-12700-kernel.0', unfortunately the device I'm working with is secure boot on so I can't modify bootloader to resolve this issue, though I'm not really sure why it's happening when I looked at BootLinux. It seems the hyp dtb handling is the same in both the "dtbo img valid" and "dtbo img invalid" cases, so not sure how it's only happening in the latter case.

Note, that I do have a blair secure boot off device that I flashed with  the same tag (KERNEL.PLATFORM.3.0.r1-12700-kernel.0) since I noticed it happened to support the chipset, but was unable to reproduce the issue there, DTBO gets applied even with a basically empty base DTB. Guessing it may be due to some change in hyp with recent SoCs.

Alex

On Tuesday, December 23rd, 2025 at 12:50 PM, Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx> wrote:

>
>
> On 12/22/25 8:02 PM, Alexander Koskovich wrote:
>
> > On 9/4/25 1:05 PM, Pavan Kondeti wrote:
> >
> > > Thanks for asking this question. I believe the overlay part needs some
> > > discussion here.
> > >
> > > I have tried this series on 8550 MTP. The overlay failed, so watchdog
> > > device did not probe. same is the case with 8750 too. It works only
> > > after applying this patch. I will test and report my observation on 8650
> > > later.
> >
> > Hi Pavan, was linked this thread after seeing what I think to be the
> > same issue on another platform,
> > but issue is a bit more serious here since bootloader fails to find a
> > DTB at all, not just overlay fails.
> > When the "arch_timer" label is missing from the base DTB on Milos,
> > ufdt_apply_overlay in bootloader
> > will fail and it looks like the DTB memory gets corrupted. If you are
> > booting without a dtbo image,
> > then you don't see the issue. Couple logs from bootloader when it happens:
> >
> > ApplyOverlay: ufdt apply overlay failed
>
>
> FWIW this comes from ABL, which is open source
>
> https://git.codelinaro.org/clo/la/abl/tianocore/edk2/
>
> You can probably deduce the correct tag from the boot logs
>
> Konrad