Re: handoff data

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

Hi,

On 7/22/25 17:46, Renaud Barbier wrote:
> Board: owc-swe550s
> RENAUD: handoff_data_get_entry hd = 0x00000000fbefc5c8, cookie = 0x28061971
> ...
> handoff 0x28061971 at 0x00000000fbefc600 (size 27560)
> handoff 0x28061974 at 0x00000000fbf031d0 (size 4)
> 
> From device_initcall:
>  handoff_data_get_entry hd = 0x00000000fbefc5c8, cookie = 0x951726fb
>  baudrate = 0, 0000000000000000 =====> 			Obviously, no copied from OCRAM
>  handoff_data_get_entry hd = 0x00000000fbefc5c8, cookie = 0x28061974
>  machine = 4, 00000000fbf031d0, 0x12345678 ==> MACHINE data is correct
> 
> So, there is a need to copy the data from OCRAM to when the memory is available.

Yes. You can see how it's done for i.MX8M by grepping for
handoff_data_move().

What we do there is passing handoff_data_move() an address in DRAM and
then we memcpy the active PBL at the start of the chainloaded image.

The active PBL has set the handoff data base pointer in the data section
and thus it just works.

Cheers,
Ahmad

> 
>>
>> Cheers,
>> Ahmad
>>
>>>
>>> Cheers,
>>> Renaud
>>>
>>>
>>
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