Re: Co-existence of GPT and fixed partitions (Was: Re: [PATCH v6 5/6] block: add support for partition table defined in OF)

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

Hi,

On 12/5/24 13:12, Ahmad Fatoum wrote:
>> Or you are telling me you had a downstream patch that declares additional
>> partition in addition to a disk with a GPT partition table?
>> If that's the case, I'm confused of why the additional partition can't
>> be declared
>> directly in GPT.
> 
> Many of the older boards supported by barebox used to place the barebox image
> and the environment prior to the first partition in the unpartitioned area.
> 
> To still be able to access them, fixed partitions were used and the rest
> of the system was described by MBR/GPT partitions.
> 
> This was partially made necessary by BootROMs having strange expectations
> of where the bootloader needs to be placed, which partially overlapped
> the MBR/GPT itself, making it difficult to define a partition for the bootloader.
> 
> For newer boards, it's more common to place the bootloader in a GPT partition
> now. barebox has no DT binding for generically describing such a GPT partition
> though, so boards may create a fixed-partition "alias" and use that.

FTR, starting with barebox v2025.03.0, barebox' default is to fix up a
partitions container with a barebox,fixed-partition compatible for
everything that's not an MTD. This avoids clashing with the binding
added here for MMCs and possibly a future binding for partitioning EEPROMs.

Cheers,
Ahmad

> 
> Cheers,
> Ahmad 
> 

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