Re: [OE-core] [PATCH v3] classes: Add a new bbclass that abstracts the generation of FIT blobs

["Nandor Han" <nandor.han@vaisala.com>]

On 2020-03-27 18:35, Richard Purdie wrote:
> On Fri, 2020-03-27 at 10:29 +0200, Nandor Han wrote:
>> FIT format is very versatile allowing various combination of booting
>> sequences. In the same time different U-Boot boot stages can use FIT
>> blobs to pack various binaries (e.g. SPL supports reading U-Boot from a
>> FIT blob). Because of the allowed level of customization, the generation
>> of a FIT blob using a fixed image tree source, becomes challenging and
>> increase the level of complexity where different configurations and
>> combinations are needed.
>>
>> This bbclass will know how to generate a FIT blob, leaving the mechanics
>> of the process (dependencies, task order...) to be handled by the users
>> of the bbclass. In the same time will allow to separate the knowledge of
>> the FIT format leaving the user code cleaner and more readable.
>>
>> Signed-off-by: Nandor Han <nandor.han@vaisala.com>
> 
> Have you considered adding automated tests for this?
> 

Thanks for feedback Rickard. I haven't considered adding any extra
tests (automate), but I think is a great idea. I'll try to have a look.

> Does adding this class remove or obsolete any of the existing
> code/support?
> 

Currently no, AFAIK. But this is only the first step and my plan is to 
go forward and update the `kernel-fitimage.bbclass` to use this class. 
This way we can very easily extend the FIT source dynamically and in the 
same time reduce the complexity of the `kernel-fitimage.bbclass`. More 
over I'm planning to create also a U-Boot related class that will be 
able to generate a FIT blobs that can contain U-Boot... and is used by SPL.

> Cheers,
> 
> Richard
> 

Nandor