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Date: Sat, 12 May 2018 19:42:49 +0200
From: Paul Cercueil <paul@crapouillou.net>
Subject: Re: [PATCH] mtd: nand: Add support for reading ooblayout from device
 tree
To: Boris Brezillon <boris.brezillon@bootlin.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
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>>  >>  My motivation is to get rid of this (move it to devicetree):
>>  >>
>>  >> 
>> https://elixir.bootlin.com/linux/latest/source/arch/mips/jz4740/board-qi_lb60.c#L93
>>  >>  And enable the support of other boards with custom OOB layouts.
>>  >
>>  > Can you list the different layouts you have? I'm pretty sure 
>> there's a
>>  > pattern. Maybe we can even deduce the layout from the page size 
>> or OOB
>>  > size.
>> 
>>  This is the other layout I have for another ingenic device:
>>  
>> http://projects.qi-hardware.com/index.php/p/qi-kernel/source/tree/od-2011-09-18/arch/mips/jz4740/board-a320.c#L125
>> 
>>  Page size and OOB size are the same between these two devices.
> 
> Indeed. Do you know if there are other kind of layouts in the wild?

I'm getting a new board in a few weeks, I'll be able to check that out.

> Note that <layout-id> can be a string, so if each each board is
> defining its own layout, you could specify the board name here.
> Otherwise, if you just have those 2 patterns, you can just name them
> "contiguous" and "interleaved".

I don't like the idea of adding board-specific data inside the driver...
I'd prefer to use the method I used in this patch, but inside the
jz4740-nand driver, if you're OK with it.

Thanks,
-Paul