From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH] ARM: OMAP3: gpmc: add BCH ecc api and modes Date: Wed, 25 Apr 2012 08:23:10 -0700 Message-ID: <20120425152310.GR3739@atomide.com> References: <1334652536-4442-1-git-send-email-ivan.djelic@parrot.com> <1335365341.6356.5.camel@koala> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-01-ewr.mailhop.org ([204.13.248.71]:45174 "EHLO mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755002Ab2DYPXO (ORCPT ); Wed, 25 Apr 2012 11:23:14 -0400 Content-Disposition: inline In-Reply-To: <1335365341.6356.5.camel@koala> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Artem Bityutskiy Cc: linux-omap@vger.kernel.org, linux-mtd@lists.infradead.org, Ivan Djelic Hi, * Artem Bityutskiy [120425 07:52]: > On Tue, 2012-04-17 at 10:48 +0200, Ivan Djelic wrote: > > This patch adds a simple BCH ecc computation api, similar to the > > existing Hamming ecc api. It is intended to be used by the MTD layer. > > It implements the following features: > > > > - support 4-bit and 8-bit ecc computation > > - do not protect user bytes in spare area, only data area is protected > > - ecc for an erased NAND page (0xFFs) is also a sequence of 0xFFs > > > > This last feature is obtained by adding a constant polynomial to > > the hardware computed ecc. It allows to correct bitflips in blank pages > > and is extremely useful to support filesystems such as UBIFS, which expect > > erased pages to contain only 0xFFs. > > > > This api has been tested on an OMAP3630 board. > > > > Signed-off-by: Ivan Djelic > > Hi Tony, > > what do you think about merging this patch? This is the enabler for > making UBIFS actually usable on OMAP platforms which use BCH ECC. There > are 2 other MTD patches which depend on this - so I wonder if it is > easier to merge this one via the MTD tree, providing it has your/others' > ack(s). Looks OK to me, however there are other pending GPMC patches to convert it to a platform device device driver. Need to look those closer though. Anyways, it's best that I queue them to avoid merge conflicts. Do you these for other changes for UBIFS? If so, I can set up an immutable branch for GPMC that you can merge in as well. Regards, Tony