mkimage: allow zynqmp to use a register initialization file

[Michal Simek]

On 6/3/26 19:51, Sean Anderson wrote:
> On 6/3/26 13:45, Erich E. Hoover wrote:
>> On Wed, Jun 3, 2026 at 11:34 AM Sean Anderson <seanga2 at gmail.com> wrote:
>>> On 6/3/26 12:25, Erich E. Hoover wrote:
>>>> ...
>>>> Yes, sort of, if you are using "zynqmpimage" instead of "zynqmpbif"
>>>
>>> I've never seen the point of BIFs; I've been able to do everything I
>>> want with zynqmpimage.
>>
>> My understanding is that "zynqmpimage" only works if you have one
>> "partition", so if you're passing the ATF or other partition data I
>> think that you have to use "zynqmpbif".
>>
> 
> I used ATF, but this was with SPL. So the boot process went something like
> 
> Boot ROM loads zynqmpimage
> - PMU firmware to PMU RAM
> - U-Boot SPL to OCRAM
> 
> U-Boot SPL loads FIT
> - ATF to OCRAM
> - U-Boot/DTB to DDR
> - Bitstream to PL
> 
> And ATF was configured to jump to DDR after initializing.
> 
> I guess if you are using FSBL that doesn't work, but IMO FSBL is yet another
> incompatible bootloader to maintain. I'd rather have a shared codebase
> (SPL/U-Boot).
> 
>>> But this info would be good to put in the commit message.
>>
>> How's this sound?:
>> ===
>> The ZynqMP Boot Image Format allows specifying the register
>> initialization file with the "[init]" attribute.  Since this
>> feature is already supported by the "zynqmpimage" backend, this
>> commit implements a binding to that existing support.
>> ===
>> ( https://lists.denx.de/pipermail/u-boot/2026-June/620814.html )
>> Please accept my apologies again for messing that up the first time around.
> 
> Actually, I liked how you explained it in your previous email
> 
> If you are using "zynqmpimage" instead of "zynqmpbif"
> then you can add the register initialization with -R. This patch
> leverages that existing capability to add support for the "[init]"
> attribute in the zynqmpbif backend:
> https://docs.amd.com/r/en-US/ug1283-bootgen-user-guide/init
> 
> We are using this feature, in combination with other zynqmpbif options, like so:
> ===
> image : {
>          [init] fsbl.int
>          [bootloader] fsbl.elf
>          [pmufw_image] pmufw.elf
>          [destination_cpu=none] fsbl.tcl
>          [destination_cpu=a53-0, exception_level=el-3] bl31.elf
>          [destination_cpu=a53-0, exception_level=el-2, load=0x08000000,
> startup=0x08000000] u-boot.bin
> }
> ===

I am reading it as request for v2 with updated commit message. That's why please 
send v2 with it.

Thanks,
Michal