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Date: Tue, 24 Aug 2010 11:56:05 +0200
From: Gernot Hoyler <Gernot.Hoyler@spansion.com>
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Subject: Re: Re: protection on cfi-flash
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 > I would expect flash_erase to get some error code in that case and
 > report it back (or if that is not possible do a readback of the data
 > to see if the erase was successful).

Erasing or programing a locked sector does not immediately issue an
error on the S29GL01GP. The status you get from the device in this
case shows a couple of toggle bit cycles before it goes back to read
array mode.

It is the responsibility of higher layers to verify erase and/or program
operations. This verification step is done e.g. in flash file systems
but not in the MTD chip driver.

--Gernot

PS: Feel free to get in direct touch with me regarding adding locking
     support to the AMD/Spansion chip driver. I can help you with this.