Re: Questions About SM8550 Support

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 2/3/26 12:12 AM, Aaron Kling wrote:
> On Mon, Feb 2, 2026 at 4:36 AM Konrad Dybcio
> <konrad.dybcio@oss.qualcomm.com> wrote:
>>
>> On 1/30/26 6:13 PM, Aaron Kling wrote:
>>> On Fri, Jan 30, 2026 at 5:01 AM Konrad Dybcio
>>> <konrad.dybcio@oss.qualcomm.com> wrote:
>>>>
>>>> On 1/27/26 11:48 PM, Aaron Kling wrote:
>>>>> I am working on the AYN Odin 2 qcs8550 series of devices, specifically
>>>>> for Android, using mainline kernel drivers. I have come across some
>>>>> missing functionality and failures that I would like to inquire about.
>>>>>
>>>>> * ABL fails to load a dtbo using a baseline dtb unmodified from
>>>>> mainline. Using changes described in the gunyah watchdog thread [0], a
>>>>> dtbo loads and the devices boot as expected. If any of the changes in
>>>>> that post don't exist in the base dtb, abl will fail to load the dtbo
>>>>> and go to the bootloader menu. This appears to be an issue in the
>>>>> baseline abl code, affecting all devices of that generation. Would it
>>>>> be allowable to merge a change adding those changes to the sm8550
>>>>> dtsi, allowing an unmodified mainline dtb to work with overlays?

[...]

>> I'd consider building full DTBs for each device
> 
> My end goal makes that difficult. I'm working on LineageOS, an open
> source AOSP fork. I am attempting to make a single build target that
> supports all four AYN qcs8550 devices. Android puts the base dtb in
> vendor_boot. The concept supports multiple dtb's, but the ids the
> bootloader uses to fetch said dtb matches across all four devices.
> Even more unfortunately, this is true for the dtbo id as well; the
> vendor did not set unique board ids for the different devices.
> However, I can pull some tricks to use a variant dtbo image per
> device. That concept isn't feasible for the vendor_boot partition. So
> I'm taking every reasonable effort to support dtbo's.
> 
> And to be fair, beyond these node name and label requirements, I have
> not seen any breakage. Once the bootloader is convinced to actually
> apply the dtbo, it works as expected.

I see

It may be that I lost some context across various threads, but IIUC
we're down to just label changes, which I suppose are generally fine..
Am I following?

Konrad