Re: [PATCH 0/3] Synchronize DTC to 1.7.2

[Marek Vasut <marek.vasut@mailbox.org>]

On 11/20/25 4:54 PM, Tom Rini wrote:

Hello Tom,

>>>>> , and then
>>>>> every follow-up location doesn't need to perform that (or possibly many
>>>>> other as well) validation checks. My impression from when I looked at
>>>>> the code last, a few year ago, was that it was designed with "validate
>>>>> with most? every? function" and we would be happy enough with "validate
>>>>> once".
>>>>
>>>> If you can make that assumption -- that whatever we feed into libfdt is
>>>> valid -- then we can simply patch out can_assume() .
>>>
>>> Maybe the question I have then is, why isn't can_assume being optimized
>>> out at compile time, if we set the mask right. Makes me wonder if
>>> there's not something to fix upstream too. Or maybe we need to change
>>> the default to higher than 0?
>>
>> Maybe because the mask is set differently for U-Boot and SPL , see:
>>
>> CONFIG_SPL_OF_LIBFDT_ASSUME_MASK=0xff
>> CONFIG_OF_LIBFDT_ASSUME_MASK=0x0
> 
> Right. We might want a different default for full U-Boot at this point
> (not assume perfect, but also not assume nothing).

For SPL, we assume perfect. For U-Boot, we assume not valid at all.

I think this configuration is actually what we want, keep SPL size 
small, perform validation of DT in U-Boot because it might come from a 
command line.

> But still, I would
> have hoped SPL growth was smaller, but perhaps I just need to
> re-evaluate things. Let me know when you have a next iteration of
> everything branch somewhere and I'll run the size growth build before
> you post if you like and we can iterate on it.
The latest is always in u-boot-sh / test-dtc branch.