[FRC] [PATCH] MTD: nand_base.c: Enable support for Samsung E-die SLC NAND

[Gupta, Pekon]

Hi Ted,

>From: Ted Juan [mailto:ted.juan at gmail.com]

>>> (b) Also, it may be the case that there few particular blocks which has gone
>>> bad and those are is showing again and again at each boot. However, If it
>>> was such a case that only some handful blocks on NAND device have gone
>>> bad, then UBI torture test [1] should have detected them and marked them
>>> bad. And those should not re-appear in next time.
>>> - You can check (b) by scrubbing all bad-blocks from u-boot
>>>   #u-boot> nand scrub.chip all
>>>   #u-boot> nand bad  (should report 0 bad blocks)
>>> - Then, re-boot and let UBI detect bad-blocks on its own using torture-test
>>> - And then again reset the system 2nd time and check newly detected bad-blocks
>>>   #u-boot> nand bad  (should report [n] bad blocks)
>>>
>
>I do the torture test in uboot.
>
>Some block data was not correct as below , and it should be pattern '0x55'.
>
>This block is not mask the bad, and sometimes the same block pass the
>torture test.
>Several blocks also have the same phenomenon.
>
>So it seems the Nand Flash problem?
>
If the same block fails and passes torture_test inconsistently, then
its mostly the problem with NAND part. As I also see that there are good
number of bit-flips (non 0xff and non 0x55 data) in the below dump,
which should _not_ be the case with fresh NAND. This is violation of
datasheet which say max allowable bit-flips = 1bit/528bytes.

Also, if you see only countable number of such blocks giving inconsistent
result, then you manually mark them bad using following command.
       u-boot>  nand markbad <block-offset>
And re-run your regression tests.
If after marking these blocks as bad, you don't see any issue for long time
That means these bad blocks were not caught during factory tests, And
there is some gap in factory test at the vendor's end, due to which these
blocks weren't caught during factory production.

>regards,
>Ted
>

with regards, pekon



>nand dump 6560000
>Page 06560000 dump:
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>01 55 55 55 55 55 ff ff  ff ff 55 55 ff ff ff ff  <--- (01)
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 55
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>55 51 55 55 55 55 ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 55
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 55 55 ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 55
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>55 54 55 55 45 51 ff ff  ff ff 55 55 ff ff ff ff  <--- (54) (45) (51)
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 55
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 55 55 ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 55
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>45 55 55 55 55 55 ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 15
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 55 51 ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff ff 55 55 55 55
>ff ff ff ff ff ff ff ff  ff ff 55 55 ff ff ff ff
>55 51 55 55 55 55 ff ff  ff ff 55 55 ff ff ff ff
>55 55 55 55 ff ff ff ff  ff ff 55 55 ff ff 55 55
>ff ff 55 55 ff ff ff ff  ff ff ff 7f 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff ff ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  ff ff ff ff ff ff ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff ff ff  55 55 ff ff 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff ff ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  ff ff ff ff ff ff ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff ff ff  55 55 ff ff 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff ff ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  ff ff ff ff ff ff ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff ff ff  55 55 ff ff 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff ff ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  ff ff ff ff ff ff ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff ff ff  55 55 ff ff 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff ff ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  ff ff ff ff ff ff ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff ff ff  55 55 ff ff 55 55 55 55
>55 55 7f ff 55 55 ff ff  ff ff ff ff 55 55 ff ff
>7f ff ff ff 55 55 ef ff  ff ff ff ff ff ff 7f ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff ff ff  55 55 ff ff 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff 7f ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  7f ff ff ff ff ff ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 7f ff ff ff  55 55 ff ff 55 55 55 55
>55 55 ff ff 55 55 ff ff  ff ff f7 ff 55 55 ff ff
>ff ff ff ff 55 55 ff ff  f7 ff ff ff ff fb ff ff
>55 55 ff ff 55 55 55 55  55 55 55 55 55 55 ff ff
>55 55 55 55 f7 ff ff ff  55 55 ff ff 55 55 55 55
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>ff ff ff ff ff ff 55 55  ff ff 55 55 55 55 55 55
>55 55 55 55 ff ff 55 55  ff ff ff ff 55 55 55 55
>55 55 ff ff ff ff ff ff  55 55 55 55 ff ff ff ff
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 ff ff
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 75 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  15 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>55 55 55 55 ff ff 55 55  55 55 55 55 ff ff 55 55
>55 55 ff ff ff ff ff ff  55 55 ff ff ff ff 55 55
>ff ff ff ff ff ff ff ff  55 55 55 55 55 55 55 55
>ff ff ff ff 55 55 ff ff  55 55 ff ff ff ff 55 55
>OOB:
>ff ff ff dd 57 ff ff df
>ff 7d ef 3e f5 ea ff 00
>fe cd eb af d8 ff ff eb
>ff 7f bf ff ff aa ff cd
>43 af fa ff d7 ff f7 ff
>f5 e0 27 00 fd dd eb 5d
>dd ff d2 ff ff 7f ff ff
>05 00 ff ff ff ff ff ff