Hi Shiva, Thanks for the sharing the information. I am using 2.4.19 kernel and its mtd system along with yaffs file system. I had enabled ECC and the page size is 512 bytes. I am trying to use nanddump utility from mtd-utils-1.0.0.tar.gz. It actually failed to communicate with mtd driver bcoz it did not find some ioctl which checks for bad block. So I commented out that part of code and when it fails to reading from the device the utility gets closed. So I commented that part so even if it fails in reading the device, it will continue to dump whatever is read. From the print message " ecc error fix performed on chunk 8573:0", the 8573 is the chunk number and when I multiply it with the page size(512) I get the offset, If I am not wrong. When I try to look into that area from the nanddump, I could see only zeros. When does a region gets filled with zeros ? I am looking for a working nanddump utility whuch uses mtd with yaffs. Can anybody give me the link or give me suggestion to build one. Shiva, I tried to return zero from a part of code which does bad block checking in yaffs. But while booting it got hung up saying that it was trying erase a bad block. Thanks, Chandru. -----Original Message----- From: yaffs-bounces@lists.aleph1.co.uk [mailto:yaffs-bounces@lists.aleph1.co.uk] On Behalf Of yaffs-request@lists.aleph1.co.uk Sent: Sunday, January 21, 2007 5:31 PM To: yaffs@lists.aleph1.co.uk Subject: yaffs Digest, Vol 20, Issue 13 Send yaffs mailing list submissions to yaffs@lists.aleph1.co.uk To subscribe or unsubscribe via the World Wide Web, visit http://lists.aleph1.co.uk/cgi-bin/mailman/listinfo/yaffs or, via email, send a message with subject or body 'help' to yaffs-request@lists.aleph1.co.uk You can reach the person managing the list at yaffs-owner@lists.aleph1.co.uk When replying, please edit your Subject line so it is more specific than "Re: Contents of yaffs digest..." Today's Topics: 1. Re: yaffs Digest, Vol 20, Issue 12 (Shiva Shankar) ---------------------------------------------------------------------- Message: 1 Date: Sat, 20 Jan 2007 08:27:31 -0800 (PST) From: Shiva Shankar Subject: [Yaffs] Re: yaffs Digest, Vol 20, Issue 12 To: yaffs@lists.aleph1.co.uk Message-ID: <20070120162731.91351.qmail@web50808.mail.yahoo.com> Content-Type: text/plain; charset="iso-8859-1" Hi Chandru, >From what I gather from your mail I think that what ever block has given you Input /output error is really bad block or its OOB area is screwed up. Do you have the nanddump? Also, it always helps if you get the dump with -p option as it clearly differentiates the data area and the OOB area and you will get a pretty output. Bad Block information is a very important information in a Flash device and you might not want to loose it. However one can screwup the bad block info by overwriting these info. There is some function in nand_base.c like XXX_isbad, the function actually checks if a block is bad and returns the result. You can change this function to return "0". By doing this you will be able to use the bad blocks that were falsely accused bad because of bad OOB management. NOTE: This is just a hack to fix blocks that have bad info written accidentally and in this process you may potentially loose an actual bad block info. After doing this you may still get input/output error if the blocks are really bad!! Have you enabled ECC in your nand driver? Which one? What is the page size of your NAND? regards, shivas yaffs-request@lists.aleph1.co.uk wrote: Send yaffs mailing list submissions to yaffs@lists.aleph1.co.uk To subscribe or unsubscribe via the World Wide Web, visit http://lists.aleph1.co.uk/cgi-bin/mailman/listinfo/yaffs or, via email, send a message with subject or body 'help' to yaffs-request@lists.aleph1.co.uk You can reach the person managing the list at yaffs-owner@lists.aleph1.co.uk When replying, please edit your Subject line so it is more specific than "Re: Contents of yaffs digest..." Today's Topics: 1. Regarding Bad blocks (Chandru) ---------------------------------------------------------------------- Message: 1 Date: Fri, 19 Jan 2007 18:07:53 +0530 From: "Chandru" Subject: [Yaffs] Regarding Bad blocks To: Message-ID: Content-Type: text/plain; charset="us-ascii" Hi All, How can I know the physical location of a file accessed for reading or writing ? I get a messages on console " ecc error fix performed on chunk 8573:0 " on the console. Is there any possibility to determine the location where this ecc fix is performed (offset from where the flash is mapped ). The number 8573 is the chunk id, I suppose. Is there any logic to find out the physical location of the chunk, I suppose the page ? When does the page gets bad blocks ? What happens while the chip is powered off when some data is being read from it ? Is there any chances of data being corrupted when chip is powered off while in read operation ? I am trying to use nanddump utility to dump the contents to a file in HEX Value. After reading the first block, I am getting Input/Output error. May be the second block has been corrupted, and the read operation fails. FYI I am using kernel 2.4.19. Does the nanddump needs any modification to ignore the BAD blocks ? Any reference docs or ideas would help me to figure it out. Thanks, Chandru. ------------------------------ _______________________________________________ yaffs mailing list yaffs@lists.aleph1.co.uk http://lists.aleph1.co.uk/cgi-bin/mailman/listinfo/yaffs End of yaffs Digest, Vol 20, Issue 12 ************************************* --------------------------------- Now that's room service! Choose from over 150,000 hotels in 45,000 destinations on Yahoo! Travel to find your fit. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://aleph1.co.uk/lurker/list/yaffs.html/attachments/20070120/742f12ee/att achment.html ------------------------------ _______________________________________________ yaffs mailing list yaffs@lists.aleph1.co.uk http://lists.aleph1.co.uk/cgi-bin/mailman/listinfo/yaffs End of yaffs Digest, Vol 20, Issue 13 ************************************* __________ NOD32 1993 (20070120) Information __________ This message was checked by NOD32 antivirus system. http://www.eset.com