From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 12 Nov 2014 10:02:54 -0800 From: Tony Lindgren To: pekon Subject: Re: [PATCH] mtd: nand: omap: Fix NAND enumeration on 3430 LDP Message-ID: <20141112180253.GJ26481@atomide.com> References: <1415185258-11747-1-git-send-email-rogerq@ti.com> <20141106180333.GZ31454@atomide.com> <545C9267.7060301@ti.com> <545C97AB.4040402@ti.com> <20141107224832.GG31454@atomide.com> <545FC08D.8000008@pek-sem.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <545FC08D.8000008@pek-sem.com> Cc: computersforpeace@gmail.com, stable@vger.kernel.org, linux-mtd@lists.infradead.org, ezequiel@vanguardiasur.com.ar, linux-omap@vger.kernel.org, dwmw2@infradead.org, Roger Quadros List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , * pekon [141109 11:31]: > On Saturday 08 November 2014 04:18 AM, Tony Lindgren wrote: > > > >Right. I doubt anybody has bch8 rootfs on LDP.. And considering u-boot > >must be ham1 to boot at all, that's what we should change for the > >devices that do not have not standardized on bch8. > > > My view on this is slightly different: > - Lately, everyone seems to have migrated to BCH8. > > - Also HAM1 does not have strength to fix bitflips in aging NAND. So if > someone already has OMAP3-LDP deployed on field then its NAND would have > already aged to such an extend that HAM1 may not be sufficient. OK so it makes sense to keep it as BCH8 then. Would be nice to get the writing u-boot from kernel issue fixed somehow though as people are hitting that for sure. > My question is.. > Moving back to HAM1 should be decided based on statistics rather than rule > of breaking backward compatibility. So please review: > (1) How many user of OMAP3-Zoom or other old boards complaining about using > BCH8 in mainline kernel? OR 0 > (2) How many users of OMAP3 legacy boards are migrating to newer kernel? Quite a few for sure, but are probably also using rootfs on MMC instead. > At-least I have not, rather most of the OMAP3 users I interacted via TI's > E2E forum wanted to migrate to BCH8 or even BCH16, as HAM1 was not > sufficient for their usage. > > So whatever you decide on this topic, please be cautious that you don't > re-invent work for yourself, as I did. It took me lot of time and testing > effort on multiple boards to migrate HAM1 to BCH8, And add BCH16 for newer > devices. Right no objections to using BCH8 for rootfs, except it stopped working over past year or so. And it seems the settings should be partition specific because of u-boot requiring HAM1. Regards, Tony From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH] mtd: nand: omap: Fix NAND enumeration on 3430 LDP Date: Wed, 12 Nov 2014 10:02:54 -0800 Message-ID: <20141112180253.GJ26481@atomide.com> References: <1415185258-11747-1-git-send-email-rogerq@ti.com> <20141106180333.GZ31454@atomide.com> <545C9267.7060301@ti.com> <545C97AB.4040402@ti.com> <20141107224832.GG31454@atomide.com> <545FC08D.8000008@pek-sem.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-02-ewr.mailhop.org ([204.13.248.72]:35411 "EHLO mho-02-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751685AbaKLSDg (ORCPT ); Wed, 12 Nov 2014 13:03:36 -0500 Content-Disposition: inline In-Reply-To: <545FC08D.8000008@pek-sem.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: pekon Cc: Roger Quadros , computersforpeace@gmail.com, dwmw2@infradead.org, ezequiel@vanguardiasur.com.ar, linux-mtd@lists.infradead.org, linux-omap@vger.kernel.org, stable@vger.kernel.org * pekon [141109 11:31]: > On Saturday 08 November 2014 04:18 AM, Tony Lindgren wrote: > > > >Right. I doubt anybody has bch8 rootfs on LDP.. And considering u-boot > >must be ham1 to boot at all, that's what we should change for the > >devices that do not have not standardized on bch8. > > > My view on this is slightly different: > - Lately, everyone seems to have migrated to BCH8. > > - Also HAM1 does not have strength to fix bitflips in aging NAND. So if > someone already has OMAP3-LDP deployed on field then its NAND would have > already aged to such an extend that HAM1 may not be sufficient. OK so it makes sense to keep it as BCH8 then. Would be nice to get the writing u-boot from kernel issue fixed somehow though as people are hitting that for sure. > My question is.. > Moving back to HAM1 should be decided based on statistics rather than rule > of breaking backward compatibility. So please review: > (1) How many user of OMAP3-Zoom or other old boards complaining about using > BCH8 in mainline kernel? OR 0 > (2) How many users of OMAP3 legacy boards are migrating to newer kernel? Quite a few for sure, but are probably also using rootfs on MMC instead. > At-least I have not, rather most of the OMAP3 users I interacted via TI's > E2E forum wanted to migrate to BCH8 or even BCH16, as HAM1 was not > sufficient for their usage. > > So whatever you decide on this topic, please be cautious that you don't > re-invent work for yourself, as I did. It took me lot of time and testing > effort on multiple boards to migrate HAM1 to BCH8, And add BCH16 for newer > devices. Right no objections to using BCH8 for rootfs, except it stopped working over past year or so. And it seems the settings should be partition specific because of u-boot requiring HAM1. Regards, Tony