From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga01.intel.com ([192.55.52.88] helo=fmsmga101-1.fm.intel.com) by canuck.infradead.org with esmtp (Exim 4.54 #1 (Red Hat Linux)) id 1FPDk2-0006Kq-IQ for linux-mtd@lists.infradead.org; Fri, 31 Mar 2006 02:08:28 -0500 Message-ID: <442CD50A.6070006@intel.com> Date: Fri, 31 Mar 2006 11:06:50 +0400 From: Alexander Belyakov MIME-Version: 1.0 To: dedekind@infradead.org References: <442B9FA5.9070901@ru.mvista.com> <442BF839.8060402@intel.com> <1143733184.3579.47.camel@sauron.oktetlabs.ru> In-Reply-To: <1143733184.3579.47.camel@sauron.oktetlabs.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Korolev, Alexey" , Vitaly Wool , "Kutergin, Timofey" , linux-mtd@lists.infradead.org Subject: Re: [PATCH/RFC] MTD: Striping layer core List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Artem B. Bityutskiy wrote: > Well, probably this is a perversion and is not needed in reality, but > still. I conceive it like this. Yo have 2 flashes. You as usually, > calculate the resulting eraseblock size. You see at the minimal I/O unit > size of both flashes and similarly calculate the resulting minimal I/O > size. So that's it. You'll end up with a though perverted, but still a > striped MTD device. First problem in case of striping NOR and NAND is a question about type of striped device. Should we report it as NOR or as NAND. I believe it is important for clients to know about that. Imagine, for example, device reported as NAND behaves as NOR or vice versa. Another problem is a difference in operation speed. Apparently you won't get any performance gain. These are only top of iceberg. Note that even plain and simple mtdconcat is not supposed to work with flashes of different types. Alexander Belyakov