Re: [PATCH v7 2/2] arm64: boot: Support Flat Image Tree

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello Tom,

On 29.11.23 20:02, Tom Rini wrote:
> On Wed, Nov 29, 2023 at 07:59:00PM +0100, Ahmad Fatoum wrote:
>> 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.
> 
> So the matching side for this series in U-Boot is:
> https://patchwork.ozlabs.org/project/uboot/list/?series=382849&state=*
> 
> And in short, for IH_TYPE_KERNEL_NOLOAD we do our best to use it
> in-place. For decompression we allocate some space to decompress to.

Thanks. I am still curious why "kernel" couldn't have been used back then
with missing entry and load address to arrive at the same result?

Thanks,
Ahmad


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