From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.de.keymile.com ([195.8.104.1]) by canuck.infradead.org with smtp (Exim 4.72 #1 (Red Hat Linux)) id 1Pkv4q-0006k7-5S for linux-mtd@lists.infradead.org; Thu, 03 Feb 2011 09:02:09 +0000 Message-ID: <4D4A6F05.30401@keymile.com> Date: Thu, 03 Feb 2011 10:01:57 +0100 From: Holger Brunck MIME-Version: 1.0 To: dedekind1@gmail.com Subject: Re: [PATCH 0/7] UBIFS: fix recovery on CFI NOR References: <1296634917-19335-1-git-send-email-dedekind1@gmail.com> <4D497663.3070806@keymile.com> <1296666971.30461.8.camel@localhost> In-Reply-To: <1296666971.30461.8.camel@localhost> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Anatolij Gustschin , "linux-mtd@lists.infradead.org" , Norbert van Bolhuis List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, On 02/02/2011 06:16 PM, Artem Bityutskiy wrote: > Hi, > > On Wed, 2011-02-02 at 16:21 +0100, Holger Brunck wrote: >> I have tested this patches on an ppc82xx and ppc83xx boards with different NOR >> flashes with different writebuffers (64 and 1024 bytes) and check wether I am >> able to mount previous created UBIFS partitions and this works without any >> problems. So the incompatbility seems to be solved. Additionaly I tried it on a >> NAND based system and this runs also without problems. > > OK, thanks! > >> Another question related to the writebuffer adaptions for UBI. What should be >> done during creation of ubi images on a host system with ubinize if your patches >> find their way in the "standard" UBI/UBIFS code. > > Nothing, when creating images you specify min. I/O size, which is 1 in > case of NOR. > >> In the past we had "only" NOR >> flashes with a writebuffer of 64 bytes and we create our ubi images without the >> -m parameter during executing ubinize for the esw image. > > No, you always specify 1. Your flash still allows writing 1 byte at a > time, and this is the minimum, so you set -m 1. > > 64 is the internal detail, the "optimal" write size. UBIFS will > automatically pick it up and will try to write in 64-byte chunks at a > time, but not always, only when it is possible. > >> Now we got a new flash >> with writebuffer = 1024. Whats the way forward in the future? Is it ok to omit >> the "-m" parameter or do we have to create the images with "-m 64" or "-m 1024"? > > Similarly, just use -m 1 > ah ok. This was exactly what I figure out from the UBI/UBIFS documentation, but due to the discussions and patches for the min I/O sizes adaptions I was a little bit unsure what to do. Thanks for the clarification. Regards Holger