Hi Wookey,
   Thanks  for your reply,
  I have attached the proc  output.
We have designed a  board with omap3 processor,I am using 2.,6.27 
kernel  these 2 GB   SLC NAND chips are from micron with  4K page size 
and 256K block size, I have made some changes to cater this.Also I am 
using 128 OOB patch which i got from net. I am using SW ECC.

I am able to detect the chip mount the device, My FS size is 900MB

I get these messages ,Could you tell me what this means..
**>> yaffs chunk 364856 was not erased
**>> yaffs chunk 364857 was not erased
**>> yaffs chunk 364858 was not erased
**>> yaffs chunk 364859 was not erased
**>> yaffs chunk 364860 was not erased
**>> yaffs chunk 364861 was not erased
**>> yaffs chunk 364862 was not erased
**>> yaffs chunk 364863 was not erased
**>> yaffs write required 119 attempts
**>> yaffs write required 2 attempts
page 351427 in gc has no object: 0 0 0
page 351430 in gc has no object: 0 0 0
page 351431 in gc has no object: 0 0 0
page 351435 in gc has no object: 0 0 0
page 351437 in gc has no object: 0 0 0
page 351438 in gc has no object: 0 0 0
page 351442 in gc has no object: 0 0 0
page 351444 in gc has no object: 0 0 0
page 351448 in gc has no object: 0 0 0
page 351451 in gc has no object: 0 0 0
page 351453 in gc has no object: 0 0 0
page 351454 in gc has no object: 0 0 0
page 351455 in gc has no object: 0 0 0
page 351459 in gc has no object: 0 0 0
page 351462 in gc has no object: 0 0 0
page 351463 in gc has no object: 0 0 0
page 351464 in gc has no object: 0 0 0
page 351465 in gc has no object: 0 0 0
page 351469 in gc has no object: 0 0 0
page 351472 in gc has no object: 0 0 0
page 351474 in gc has no object: 0 0 0
page 351475 in gc has no object: 0 0 0
page 351479 in gc has no object: 0 0 0
page 351481 in gc has no object: 0 0 0
page 351485 in gc has no object: 0 0 0
**>> yaffs write required 2 attempts
page 47613 in gc has no object: 47973 0 0
page 47614 in gc has no object: 47973 0 0
page 4297 in gc has no object: 3405 0 0
BRP 1 0


Thanks,
Ramprasad.
> +++ Ramprasad B [2009-03-08 00:44 +0530]:
>  
>> Hi,
>>  Is there a yaffs  support for 2GB SLC nand.
>>     
>
> Yes - yaffs2 should 'just work' on such a device - it's what it is
> designed for.
> I see you have already posted about having a problem with such a chip,
> but got no response.
>
> Some more details on what you are doing would help. Is it new
> hardware? Is it known to be working? How is the flash controller
> implemented? How is the ECC being calculated - software or hardware?
>
> What OS are you using?
>
> Which yaffs and OS versions are you using?
>
> If Linux, what does /proc/yaffs say?
>
> Wookey
>   

------------------------------------------------------------------------

 YAFFS built:Mar  7 2009 16:38:37
$Id$
$Id$

Device 0 "File-system NAND -1"
startBlock......... 0
endBlock........... 5699
totalBytesPerChunk. 4096
nDataBytesPerChunk. 4096
chunkGroupBits..... 0
chunkGroupSize..... 1
nErasedBlocks...... 23
nReservedBlocks.... 5
blocksInCheckpoint. 0
nTnodesCreated..... 45800
nFreeTnodes........ 1505
nObjectsCreated.... 48000
nFreeObjects....... 13
nFreeChunks........ 77310
nPageWrites........ 464233
nPageReads......... 250117
nBlockErasures..... 3385
nGCCopies.......... 57841
garbageCollections. 3384
passiveGCs......... 1347
nRetriedWrites..... 26360
nShortOpCaches..... 10
nRetireBlocks...... 0
eccFixed........... 662
eccUnfixed......... 10679
tagsEccFixed....... 0
tagsEccUnfixed..... 0
cacheHits.......... 58887
nDeletedFiles...... 0
nUnlinkedFiles..... 2998
nBackgroudDeletions 0
useNANDECC......... 1
isYaffs2........... 1
inbandTags......... 0