Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754520Ab2JOS5X (ORCPT ); Mon, 15 Oct 2012 14:57:23 -0400 Received: from mail-we0-f174.google.com ([74.125.82.174]:63287 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753157Ab2JOS5U (ORCPT ); Mon, 15 Oct 2012 14:57:20 -0400 From: Peter Korsgaard To: "Philip\, Avinash" Cc: , , , afzal@ti.com, linux-doc@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, ivan.djelic@parrot.com, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 3/4] ARM: OMAP2: gpmc: Add support for BCH ECC scheme References: <1349274589-11389-1-git-send-email-avinashphilip@ti.com> <1349274589-11389-4-git-send-email-avinashphilip@ti.com> Date: Mon, 15 Oct 2012 20:48:30 +0200 In-Reply-To: <1349274589-11389-4-git-send-email-avinashphilip@ti.com> (Avinash Philip's message of "Wed, 3 Oct 2012 19:59:48 +0530") Message-ID: <87vcebvaf5.fsf@macbook.be.48ers.dk> User-Agent: Gnus/5.110009 (No Gnus v0.9) Emacs/22.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1326 Lines: 36 >>>>> Philip, Avinash writes: > Add support for BCH ECC scheme to gpmc driver and also enabling multi > sector read/write. This helps in doing single shot NAND page read and > write. > ECC engine configurations > BCH 4 bit support > 1. write => ECC engine configured in wrap mode 6 and with ecc_size0 as 32. > 2. read => ECC engine configured in wrap mode 1 and with ecc_size0 as > 13 and ecc_size1 as 1. > BCH 8 bit support > 1. write => ECC engine configured in wrap mode 6 and with ecc_size0 as 32. > 2. read => ECC engine configured in wrap mode 1 and with ecc_size0 as > 26 and ecc_size1 as 2. > Note: For BCH8 ECC bytes set to 14 to make compatible with RBL. On what device? In the am335x TRM (spruh73f.pdf) figure 26-15 (pg 4273) the rom code is documented to not use any padding on the ECC bytes (E.G. oob 2..53): http://www.ti.com/litv/pdf/spruh73f I see the driver in the u-boot-am33x tree (ti81xx_nand.c) seems to use 4x14 bytes as well though, so perhaps that's a bug in the documentation instead? -- Bye, Peter Korsgaard -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/