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Date: Thu, 20 Jan 2011 15:24:46 +0100
From: Holger Brunck <holger.brunck@keymile.com>
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Subject: MTD concat support for linux and UBI
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Cc: Stefan Roese <sr@denx.de>, "agust@denx.de" <agust@denx.de>,
	Detlev Zundel <dzu@denx.de>
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Hi all,
I have got a general question to the MTD concat feature in Linux. Is it allowed
to concatenate NOR flashes with different writebuffersizes? Currently the code
allows this.
If so I see a problem for different sizes when dealing with UBI volumes
comprehending such flashes. Some days ago some patches were added to adjust the
min I/O size for UBI to the writebuffersize of the flash. If now two flashes
with different writebuffersizes are concatenated whats the way forward? I see
two solutions:
1) Using the writebuffersize from the flash with the largest writebuffer for min
I/O size in UBI.
2) Adapting the concat feature in Linux to forbid concatenating flashes with
different writebuffersizes.

Best regards
Holger Brunck