Re: [PATCH v12 1/3] dt-bindings: mtd: Describe MTD partitions concatenation

[Rob Herring <robh@kernel.org>]

On Wed, Feb 12, 2025 at 05:18:39PM +0100, Miquel Raynal wrote:
> On 12/02/2025 at 10:06:59 -06, Rob Herring <robh@kernel.org> wrote:
> 
> > On Wed, Feb 12, 2025 at 09:25:53AM +0100, Miquel Raynal wrote:
> >> Hi,
> >> 
> >> >> The partitions that gets created are
> >> >> part0_0
> >> >> part1_1
> >> >> part0_1-part1_0-concat
> >> >
> >> > 'part-concat' doesn't work if you have multiple sets of partitions you 
> >> > want to concatenate.
> >> >
> >> > I think you need something like 'prev-partition' or 'next-partition' in 
> >> > the partition nodes to create a linked list of partitions. Hopefully, 
> >> > you don't need both properties, but you do have to scan everything to 
> >> > figure out which ones are concatenated or not. For example, no property 
> >> > can mean not concatenated or last partition if you use 'next-partition'. 
> >> 
> >> Out of curiosity, would the chosen node be eligible as a central place
> >> where to look at?
> >
> > Why would you need that?
> 
> I'm talking about storing in a central place all the concatenated
> partitions. Your proposal with "next-partition" works fine if we locate
> it inside the 'partitions' node, but I feel like the 'part-concat'
> instead was not fitting very well there. So I was wondering in this case
> if moving the concatenation of the partitions would be eligible to the
> chosen node, or if that's reserved to *very* few properties (and should
> remain like that).

You would have to solve the same problem as this patchset which is how 
to support N sets of concatenated partitions.

In general though, we add new things to /chosen very carefully. It's 
usually "things the bootloader configured/enabled" which I don't think 
this qualifies as. 

Rob