Hi,
a few more comments after decompiling the FIT image:
On 29.11.23 18:21, Simon Glass wrote:
> + with fsw.add_node('kernel'):
> + fsw.property_string('description', args.name)
> + fsw.property_string('type', 'kernel_noload')
The specification only says no loading done, but doesn't explain what it
means for a bootloader to _not_ load an image. Looking into the U-Boot commit
b9b50e89d317 ("image: Implement IH_TYPE_KERNEL_NOLOAD") that introduces this,
apparently no loading means ignoring load and entry address?
I presume missing load and entry is something older U-Boot versions
were unhappy about? Please let me know if the semantics are as I understood,
so I can prepare a barebox patch supporting it.
> + fsw.property_string('arch', args.arch)
> + fsw.property_string('os', args.os)
> + fsw.property_string('compression', args.compress)
> + fsw.property('data', data)
> + fsw.property_u32('load', 0)
> + fsw.property_u32('entry', 0)
> +
> +
> +def finish_fit(fsw, entries):
> + """Finish the FIT ready for use
> +
> + Writes the /configurations node and subnodes
> +
> + Args:
> + fsw (libfdt.FdtSw): Object to use for writing
> + entries (list of tuple): List of configurations:
> + str: Description of model
> + str: Compatible stringlist
> + """
> + fsw.end_node()
> + seq = 0
> + with fsw.add_node('configurations'):
> + for model, compat in entries:
> + seq += 1
> + with fsw.add_node(f'conf-{seq}'):
> + fsw.property('compatible', bytes(compat))
The specification says that this is the root U-Boot compatible,
which I presume to mean the top-level compatible, which makes sense to me.
The code here though adds all compatible strings from the device tree though,
is this intended?
> + fsw.property_string('description', model)
> + fsw.property_string('type', 'flat_dt')
> + fsw.property_string('arch', arch)
> + fsw.property_string('compression', compress)
> + fsw.property('compatible', bytes(compat))
I think I've never seen a compatible for a fdt node before.
What use does this serve?
Cheers,
Ahmad
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