From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx.dave-tech.it ([2.229.21.40]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZKMNI-0000Fb-IY for linux-mtd@lists.infradead.org; Wed, 29 Jul 2015 08:06:05 +0000 Subject: Re: [PATCH 5/6] mtd: nand: gpmi: correct bitflip for erased NAND page To: linux-mtd@lists.infradead.org, Han Xu References: <1438105841-22314-1-git-send-email-b45815@freescale.com> Cc: shijie8@gmail.com, dwmw2@infradead.org, computersforpeace@gmail.com, boris.brezillon@free-electrons.com, fabio.estevam@freescale.com, hofrat@osadl.org, linux-kernel@vger.kernel.org From: Andrea Scian Message-ID: <55B88952.1060709@dave-tech.it> Date: Wed, 29 Jul 2015 10:05:38 +0200 MIME-Version: 1.0 In-Reply-To: <1438105841-22314-1-git-send-email-b45815@freescale.com> Content-Type: text/plain; charset=iso-8859-15; format=flowed Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Dear Han Xu, Il 28/07/2015 19:50, Han Xu ha scritto: > i.MX6QP and i.MX7D BCH module integrated a new feature to detect the > bitflip number for erased NAND page. So for these two platform, set the > erase threshold to gf/2 and if bitflip detected, GPMI driver will > correct the data to all 0xFF. That's an iteresting feature of iMX6QP We were discussing about erased NAND page bitflip in MTD ML a few days ago. Is gf/2 a right value to choose? Why? IIUC, in a previuos MTD-level patch [1] Brian used ECC strength as threshold. Could you please also share with which NAND device you tested this patch? Kind regards and TIA, -- Andrea SCIAN DAVE Embedded Systems [1] http://article.gmane.org/gmane.linux.drivers.mtd/52216