From mboxrd@z Thu Jan 1 00:00:00 1970 From: Charles Manning Subject: No more software ECC in omap2.c NAND driver. Why? Date: Thu, 18 Nov 2010 14:06:15 +1300 Message-ID: <201011181406.15212.manningc2@actrix.gen.nz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.scorch.co.nz ([27.110.127.199]:36166 "HELO scorch.co.nz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with SMTP id S1753641Ab0KRBM5 (ORCPT ); Wed, 17 Nov 2010 20:12:57 -0500 Content-Disposition: inline Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "linux-omap@vger.kernel.org" Between 2.6.35 and 2.6.36 there have need quite a few changes in the NAND driver, including a change from software to hardware ECC. The new code has hardware ECC forced on by: #define CONFIG_MTD_NAND_OMAP_HWECC I am surprised that this was done. Surely this should have been a Kconfig option to select either sw ECC or hw ECC? Does moving to hardware ECC to the exclusion of software ECC reduce functionality? Does the new hwecc scheme still support sub-page writes or does it only provide full page writes? If sub-page writes are lost then this has a ripple effect in breaking the way some UBI stuff works. -- Charles