From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout01.sul.t-online.com ([194.25.134.80]) by pentafluge.infradead.org with esmtp (Exim 4.30 #5 (Red Hat Linux)) id 1BFsrR-0003jZ-Sp for linux-mtd@lists.infradead.org; Tue, 20 Apr 2004 11:52:17 +0100 From: tglx@linutronix.de (Thomas Gleixner) To: Shen Aaron-r62966 , "'tglx@linutronix.de'" , linux-mtd@lists.infradead.org Date: Tue, 20 Apr 2004 12:47:39 +0200 References: <01139FC052A0D411900B00508B9535FC13AC404A@ZCH07EXM04.corp.mot.com> In-Reply-To: <01139FC052A0D411900B00508B9535FC13AC404A@ZCH07EXM04.corp.mot.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200404201247.39527.tglx@linutronix.de> Subject: Re: ECC byte 4 and 5 not equal to what have just been writen Reply-To: tglx@linutronix.de List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tuesday 20 April 2004 12:37, Shen Aaron-r62966 wrote: > > -----Original Message----- > > On Tuesday 20 April 2004 11:40, Shen Aaron-r62966 wrote: > > So you are debugging your bootloader code and not kernel code ? > > Did you copy the code from 2.4.18 ? If yes, use code from > > actual MTD CVS. > > If no, which version of MTD code did you use to copy from ? > > Yes, right. I'm debugging my bootloader code. I'm using the 2.4.18 kernel, > so I didn't use the code from actual MTD CVS. There're many differences for > the actual CVS, for example, the nand_ecc.h and other head files are added > into linux/mtd/. I don't think it's a good choice to use the mtd code from > actual CVS if it's not a known problem. And I'm not sure whether such > update will do harm to my system. I think the code in 2.4.18 should work > for it. But I need to find out what's the problem. Hmm, known problem is a nice phrase. The code in 2.4.18 was not used in production AFAIK. All you need is pageprogramming which is quite straight forward: Write the start programm command Write out 512 byte data + 16 byte oob Write the programm command Wait for ready > > The page write function is the right place to look > > Yes, The only step before I re-read the oob data is the page write > function. But I have added more debugging information into this function > and still can't find the causing. Is it possible that the Nand Flash > Controller does some operation after a page has been writen? Is this the builtin controller on iMX2 ? I dont know, what this does, as I have no datasheet. The product brief tells something about automatic ECC... Maybe you have to check this first -- Thomas ________________________________________________________________________ "Free software" is a matter of liberty, not price. To understand the concept, you should think of "free" as in "free speech,'' not as in "free beer". ________________________________________________________________________ linutronix - competence in embedded & realtime linux http://www.linutronix.de mail: tglx@linutronix.de