[PATCH 4/4] mtd: nand: nand_mxs: Add subpage read support

[Sascha Hauer]

On Wed, May 18, 2016 at 08:52:16AM +0200, Stefan Christ wrote:
> Hi Sascha,
> 
> On Tue, May 10, 2016 at 08:24:43AM +0200, Sascha Hauer wrote:
> > subpage read support can significantly speed up scanning UBI volumes, so
> > add support for it. This is inspired by the corresponding Kernel commit.
> > Unlike in the kernel we add subpage read support for i.MX28 aswell.
> > Testing it on i.MX28 revealed no problems.
> > 
> > Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> 
> Here is my 
> 
>     Tested-by: Stefan Christ <s.christ at phytec.de>
> 
> I measured the ubiattach time for two different NAND chips after an ubiformat
> on the devices. It's around 30% faster. Here are the results:

Thanks for testing this.

The results become even better with bigger pages. I have a board with 8k
page Nand here. The scanning time reduced from 31s to 3.5s.

Sascha

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