Bounlith,

            I worked through this several months ago. Cat won’t get everything you need from the mtd device, as YAFFS2 uses the out-of-bounds area. You will need to use the nanddump utility.

                        John

From: yaffs-bounces@lists.aleph1.co.uk [mailto:yaffs-bounces@lists.aleph1.co.uk] On Behalf Of Sirivong Bounlith
Sent: Tuesday, September 28, 2010 4:48 AM
To: yaffs@lists.aleph1.co.uk
Subject: [Yaffs] How to dump/flash a YAFFS2 image?

Hello,

I need to dump a NAND device (formatted to YAFFS2) in an image, then write this image to the NAND emulated device on a linux computer.

To get image, I have done a cat of the device:
   cat /dev/mtd/mtd3 > <path>/yaffs2image.img

I get a 150 MB file. To write the image to the NAND emulated device, I do this:
    modprobe mtdblock
    modprobe mtdchar
    modprobe nandsim first_id_byte=0x20 second_id_byte=0x71
    mount -t yaffs /dev/mtdblock0 /media/nand
    cat yaffs2image.img > /dev/mtdblock0

In result, /media/nand contents only a "lost + found" dir. But making a cat on mtdblock0 ouputs something which seems to be the contents of yaffs2image.img. I thought I retrieve the files of the original YAFFS2 device, including all its clusters.

Is there a way to get a dump of a YAFFS2 device, and to flash the dump to another device (emulated or not)?

Thanks.

-- 
Bounlith Sirivong.