JFFS2 on NAND, Magic bitmask 0x1985 not found

Pathompong Puengrostham jay4mail at yahoo.com
Wed Jul 14 05:55:49 EDT 2004


Thomas Gleixner wrote:
> On Wed, 2004-07-14 at 06:57, Pathompong Puengrostham wrote:
> 
>>Hi,
>>
>>I just found the problem. It is that my NAND flash CE pin is not driven 
>>by GPIO. It is driven by CS from the CPU. Here is the change that I made.
> 
> 
> Ok, I accept the change in nand_verify_pages. I expected this to break,
> as it was stated in the comment. But for sure we will not invent a new
> CONFIG_ switch, we have an options field for such stuff already, also
> using a wait for ready there in any case will be enough.
> 
> 
>>I also had to add the following to my nand_init().
>>
>>for (i = 0; nand_flash_ids[i].name != NULL; i++)
>>	nand_flash_ids[i].options |= NAND_NO_AUTOINCR;
> 
> 
> Sorry, thats crap. The options are defined in nand_ids.c and are not a
> subject to be modified anywhere else. If you want to have the
> NO_AUTOINCR option set for your board, then set it in the options field
> before calling nand_scan. The bit is not overwritten by the option init
> in nand_scan.
> 

Thank you for pointing that out. I just read the nand_scan code. I
didn't know I can do that. I copied the code from spia.c and changed
only the low-level stuff.

> Which chiptype are you using exactly? 
> 

I'm using Samsung K9F5608U0C.

> The changes you made make not really sense as you put in delays which
> are neccecary for chips, which do autoincrement. Those chips which can
> not autoincrement do neither need a wait nor a deselect/select after a
> page is read.
> 
> tglx
> 

The chip I'm using do autoincrement but I thought that after CE goes
high I have to send the read command again which is not correct.
Now I don't set NAND_NO_AUTOINCR and it works good. But I still need the
delays.

Jay




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