Re: Help needed with MTD on AT91SAM9263-EK please.

[James <jamessteward@optusnet.com.au>]

Hi Richard,

On Tue, 2008-05-27 at 09:42 +0200, Richard Genoud wrote:
> well, I would say hardware failure, as far as we all used this board
> without any problem.

It's good to know the problem is (hopefully) isolated.  After the test
below, I feel it might be more than just a hardware failure though.

> Maybe a last test to be sure :
> flash_eraseall /dev/mtd0
> dd if=/dev/zero bs=2K count=1 of=/dev/mtd0
> nanddump -p -l2048 /dev/mtd0
> 
> (try to write a page and read it back).
> 
> if you can post this dump, I'm curious...

root@at91sam9263ek:~/mtd-tools$ ./flash_eraseall /dev/mtd0
Erasing 128 Kibyte @ 3ee0000 -- 99 % complete.
root@at91sam9263ek:~/mtd-tools$ dd if=/dev/zero bs=2k count=1
of=/dev/mtd0
1+0 records in
1+0 records out
root@at91sam9263ek:~/mtd-tools$ ./nanddump -p -l2048 /dev/mtd0
ECC failed: 0
ECC corrected: 0
Number of bad blocks: 0
Number of bbt blocks: 0
Block size 131072, page size 2048, OOB size 64
Dumping data starting at 0x00000000 and ending at 0x00000800...
0x00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
<skip all zeros>
0x000007e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x000007f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Hmm.  So I tried a block that previously had problems with mount.

root@at91sam9263ek:~/mtd-tools$ dd if=/dev/zero bs=2k count=1 seek=5120
of=/dev/mtd0    
1+0 records in
1+0 records out
root@at91sam9263ek:~/mtd-tools$ ./nanddump -p -l2048
-s0xa00000 /dev/mtd0
ECC failed: 0
ECC corrected: 0
Number of bad blocks: 0
Number of bbt blocks: 0
Block size 131072, page size 2048, OOB size 64
Dumping data starting at 0x00a00000 and ending at 0x00a00800...
0x00a00000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x00a00010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x00a00020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
<snip all zeros>
0x00a007e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x00a007f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  OOB Data: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

And an unwritten to page...

root@at91sam9263ek:~/mtd-tools$ ./nanddump -p -l2048
-s0xdc0000 /dev/mtd0
ECC failed: 0
ECC corrected: 0
Number of bad blocks: 0
Number of bbt blocks: 0
Block size 131072, page size 2048, OOB size 64
Dumping data starting at 0x00dc0000 and ending at 0x00dc0800...
0x00dc0000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
0x00dc0010: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
0x00dc0020: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
<snip all 0xff>

So, a page at a time seems ok?

I wonder, what markings are on your CPU and NAND flash?  I have;
AT91SAM9263 CU-ES 0747 8 QH59R.07
0742 29F2G08AAC WP C LJK6

I assume some of this will be a batch code, but I wonder if there's been
a die shrink that's caused some marginal timing issue?

Regards,
James.