[U-Boot-Users] RFC:new multi image format

[Tolunay Orkun <listmember@orkun.us>]

Kumar Gala wrote:
> The current multi image format doesn't really provide any information  
> about what the images contained inside the multi image are.
>
> I'm suggesting we add a new ih_type, IH_TYPE_MULTI_V2 in which we  
> have an expanded header for each 'sub image' to describe more details  
> about it.
>
> I wanted to see what information people felt was important to keep  
> track of for the 'sub images'.
>
> struct sub_image_header {
> 	uint32_t	ih_type;	/* sub image type */
> 	uint32_t	ih_size;	/* sub image size *
> 	uint32_t	ih_comp;	/* compress type */
> 	uint64_t	ih_load;	/* Data  Load  Address */
> 	uint64_t	ih_ep;		/* entry point */
> 	uint8_t         ih_name[IH_NMLEN];
> }
>
> Are other fields useful or should we just duplicate the image_header  
> completely?
>
> -

I agree something like (per image header) is needed. I would take this 
an opportunity to add a uint8_t[] field to add version information that 
could be filled by an build script if desired. In my previous work, we 
needed a version field to display/verify before allowing the update in 
Linux based software update (and making sure the image for board A was 
not being attempted for board B). We abused the name/description field 
for this purpose which was not the ideal solution.

I think we can incorporate this additional header so that if the new 
image is fed to an old u-boot it would still be acceptable. Perhaps we 
can group sub-image headers after the offset table but before the actual 
images.

Best regards,
Tolunay