From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from VA3EHSOBE009.bigfish.com (va3ehsobe006.messaging.microsoft.com [216.32.180.16]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (Client CN "mail.global.frontbridge.com", Issuer "Microsoft Secure Server Authority" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 6FDE5B6F64 for ; Tue, 23 Aug 2011 02:01:12 +1000 (EST) Message-ID: <4E527C91.6080009@freescale.com> Date: Mon, 22 Aug 2011 10:58:09 -0500 From: Scott Wood MIME-Version: 1.0 To: Subject: Re: [PATCH v3] mtd/nand : workaround for Freescale FCM to support large-page Nand chip References: <1313634783-8855-1-git-send-email-b35362@freescale.com> <4E4D452C.7050805@parrot.com> <4E4DD661.5080006@freescale.com> <4E4E2571.20409@parrot.com> <4E4EA70B.9050203@freescale.com> <1314010719.2644.114.camel@sauron> In-Reply-To: <1314010719.2644.114.camel@sauron> Content-Type: text/plain; charset="UTF-8" Cc: "linuxppc-dev@ozlabs.org" , "linux-mtd@lists.infradead.org" , LiuShuo , "dwmw2@infradead.org" , Matthieu CASTET List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 08/22/2011 05:58 AM, Artem Bityutskiy wrote: > On Fri, 2011-08-19 at 13:10 -0500, Scott Wood wrote: >> On 08/19/2011 03:57 AM, Matthieu CASTET wrote: >>> How the bad block marker are handled with this remapping ? >> >> It has to be migrated prior to first use (this needs to be documented, >> and ideally a U-Boot command provided do do this), or else special >> handling would be needed when building the BBT. The only way around >> this would be to do ECC in software, and do the buffering needed to let >> MTD treat it as a 4K chip. > > It really feels like a special hack which would better not go to > mainline - am I the only one with such feeling? If yes, probably I am > wrong... While the implementation is (of necessity) a hack, the feature is something that multiple people have been asking for (it's not a special case for a specific user). They say 2K chips are getting more difficult to obtain. It doesn't change anything for people using 512/2K chips, and (in its current form) doesn't introduce significant complexity to the driver. I'm not sure how maintaining it out of tree would be a better situation for anyone. -Scott