From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.bootlin.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fmEqy-0001L7-Hu for linux-mtd@lists.infradead.org; Sun, 05 Aug 2018 08:57:34 +0000 Date: Sun, 5 Aug 2018 10:57:17 +0200 From: Boris Brezillon To: Raphael Pereira Cc: miquel.raynal@bootlin.com, linux-mtd@lists.infradead.org Subject: Re: Suport for gf_len 14 in gpmi-nand for i.MX23 using Software BCH ECC Message-ID: <20180805105717.4aab931b@bbrezillon> In-Reply-To: References: <20180804115555.667b3fb8@xps13> <20180804193307.0ca82318@xps13> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Raphael, On Sat, 4 Aug 2018 21:39:13 -0300 Raphael Pereira wrote: > Hi Miqu=C3=A8l, >=20 > This old thread mentions the exact same part I am trying to use and it > seems to work on i.MX6 SOLO, which supports 40bit ECC strengh, so I > think the MLC issue is not the case, although I could not find the > solution used as it seems it is not explicit in the thread: >=20 > http://lists.infradead.org/pipermail/linux-mtd/2015-April/058901.html Trust me, getting the proper ECC config in place is just a tiny part of the problem. I'm not saying supporting MLC NANDs is impossible, but it requires spending a non-negligible amount of time to make it work reliably (see [1] and [2] if you need more details). Regards, Boris [1]https://events.static.linuxfound.org/sites/events/files/slides/brezillon= -mlc-nand_0.pdf [2]https://elinux.org/images/5/54/Weinberger.pdf