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Subject: Re: [PATCH] mtd: nand: Disable subpage writes for drivers without
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From: Scott Wood <scottwood@freescale.com>
To: "Gupta, Pekon" <pekon@ti.com>
Date: Fri, 11 Apr 2014 15:10:23 -0500
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Cc: David Woodhouse <David.Woodhouse@intel.com>, "Huang Shijie
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On Fri, 2014-04-11 at 06:35 +0000, Gupta, Pekon wrote:
> As per [1] and [2], If the subpage is _not_ supported then VID-header offset
> should be aligned to  PAGE_SIZE boundary. And it has implications on LEB size
> calculation too. I don't know how it was working earlier but if the earlier
> UBI images were using 512 as VID Header offset even without subpage
> Support then it's incorrect configuration.

I believe what was happening before was full page writes with only
subpage content (the rest left at 0xff).

> Now whether we still want backward compatibility for something which was
> incorrect, is something I leave it for Maintainers {Artem, Brian} to decide.

Why is it incorrect?  Subpage writes were happening -- if they weren't,
then we wouldn't have seen problems on IFC without that flag.

-Scott