mkimage: allow zynqmp to use a register initialization file

[Erich E. Hoover]

On Wed, Jun 3, 2026 at 9:55 AM Sean Anderson <seanga2 at gmail.com> wrote:
> Please add a commit message.

My apologies to everyone.  The checkpatch.pl script caught that and,
since I changed the title a little, I accidentally uploaded the wrong
version.

> And isn't this already possible with -R ?

Yes, sort of, if you are using "zynqmpimage" instead of "zynqmpbif"
then you can add the register initialization with -R.  The 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
}
===

Best,
Erich