From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-out.m-online.net ([2001:a60:0:28:0:1:25:1]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1d3gc8-0006dc-Qw for linux-mtd@lists.infradead.org; Thu, 27 Apr 2017 10:25:35 +0000 Received: from frontend01.mail.m-online.net (unknown [192.168.8.182]) by mail-out.m-online.net (Postfix) with ESMTP id 3wDCkV375nz1qqkN for ; Thu, 27 Apr 2017 12:25:06 +0200 (CEST) Received: from localhost (dynscan01.mnet-online.de [192.168.6.70]) by mail.m-online.net (Postfix) with ESMTP id 3wDCkV1Vkrz3hhS7 for ; Thu, 27 Apr 2017 12:25:06 +0200 (CEST) Received: from mail.mnet-online.de ([192.168.8.182]) by localhost (dynscan01.mail.m-online.net [192.168.6.70]) (amavisd-new, port 10024) with ESMTP id jyTl6Mr5_6p5 for ; Thu, 27 Apr 2017 12:25:03 +0200 (CEST) Received: from jawa (89-77-92-62.dynamic.chello.pl [89.77.92.62]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA for ; Thu, 27 Apr 2017 12:25:03 +0200 (CEST) Date: Thu, 27 Apr 2017 12:25:02 +0200 From: Lukasz Majewski To: linux-mtd@lists.infradead.org Subject: Problem with NAND memory data retention Message-ID: <20170427122502.285d16ba@jawa> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Dear All, I'd like to ask you for sharing your experience with NAND Flash devices - which may be older that their data retention time. I've a problem with Flash NAND memory (Samsung 128Mx8). In the data sheet [1] the manufacturer claims that it has 10 years for data retention. The device equipped with it is a bit older than 10 years. How one can diagnose that data retention time for NAND Flash has been exceeded? Is that: - The number of bit flip errors on a RW page so large that ECC cannot fix it? - Or are whole RW pages erased (0xFF)/corrupted/cleared (0x00)? - Or any other evidence? Thanks in advance for your help. [1] - http://www.sst-ic.com/File/Seriea/PDF/100923163334f47b2ce6-13b7-43d0-9b8c-ec1c75ca2c6f.pdf Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de