[PATCH v2 1/2] scripts/Makefile.xpl: Align filtered DTB to 8-byte within multidtb.fit

[Marek Vasut]

On 1/12/26 6:25 PM, Padhi, Beleswar wrote:
> 
> On 1/12/2026 8:09 PM, Marek Vasut wrote:
>> On 1/12/26 11:11 AM, Beleswar Padhi wrote:
>>> When CONFIG_SPL_MULTI_DTB_FIT is enabled, multiple device trees are
>>> packed inside the multidtb.fit FIT image. While the individual DTBs
>>> and the FIT image start address are 8-byte aligned, the DTBs embedded
>>> within the FIT image are not guaranteed to maintain 8-byte alignment.
>>
>> Because DT properties are 4-byte aligned, and fitImage is a DT with 
>> long binary strings encoded in them. But that is not the case here, 
>> because the invocation does use mkimage -E .
>>
>> Therefore I see two issues:
>> - Should the code which handles LEGACY fitImages with 4-byte alignment 
>> be fixed to relocate the blobs ? I think yes.
> 
> 
> This we can fix in the Makefile via the dd command as suggested by Tom.

My concern is about LEGACY fitImages (means already generated ones), not 
newly generated ones.

>> - Should mkimage -E align blobs to 8 bytes by default ? I think yes, 
>> and frankly, I thought it does so already, but apparently not.
> 
> 
> This can be done, but should it be? Not all FITs demand an 8-byte
> alignment right? It is only the FDT which requires this.
Maybe if image type is flat_dt, it should be implicitly 8-byte aligned 
then ?