problem writing to /dev/mtd0

problem writing to /dev/mtd0

[Paul van Gool]

Hi,

I'm trying to read and write from/to a flash partition using its char
device. Reading seems to work fine but I can't seem to get writing  to
work.

I'm using a SolutionEngine7751 dev board, Linux 2.4.20 and the MTD release
that was part of that kernel. The error I get is:

Last[3] is cba4cda6, datum is 34333231

Looking at Last[4] during the 10000 write attempts, it seems its value
seems to alternate between cba4cda6 and cbe4cde6.

The errno I get back is 5, and is EIO.

Boottime info regarding the chips is:

Amd/Fujitsu Extended Query Table v1.0 at 0x0040
Solution Engine FLASH: JEDEC Device ID is 0xC4. Assuming broken CFI table.
Solution Engine FLASH: Swapping erase regions for broken CFI table.
number of CFI chips: 1
Solution Engine: Flash at 0x00000000, EPROM at 0x01000000
Using configured partition at 0x00020000.
Creating 4 MTD partitions on "Solution Engine FLASH":
0x00000000-0x00020000 : "Boot loader"
0x00020000-0x000e0000 : "Kernel"
0x000e0000-0x00300000 : "Root filesystem"
0x00300000-0x00400000 : "JFFS segment"

I use this flash chip through its block device all the time and writing
through that device (/dev/mtdblock0) hasn't been an issue.

Any ideas?

Thanks.

Paul
-- 
Paul van Gool                                               Rincon Networks
paul.vangool@rinconnetworks.com                              (805)-705-1442

Re: problem writing to /dev/mtd0

[David Woodhouse]

On Fri, 2003-11-14 at 16:25 -0800, Paul van Gool wrote:
> Hi,
> 
> I'm trying to read and write from/to a flash partition using its char
> device. Reading seems to work fine but I can't seem to get writing  to
> work.

> I use this flash chip through its block device all the time and writing
> through that device (/dev/mtdblock0) hasn't been an issue.

Did you erase the block in question first?

-- 
dwmw2

Re: problem writing to /dev/mtd0

[Paul van Gool]

Yes, I did. It seems to work fine on one of my other dev boards btw. So it
may be that the first board is having issues and it's not the software. I'll
dig some more.

Thanks.

Paul

On Sat, Nov 15, 2003 at 08:31:03AM +0000, David Woodhouse wrote:
> On Fri, 2003-11-14 at 16:25 -0800, Paul van Gool wrote:
> > Hi,
> > 
> > I'm trying to read and write from/to a flash partition using its char
> > device. Reading seems to work fine but I can't seem to get writing  to
> > work.
> 
> > I use this flash chip through its block device all the time and writing
> > through that device (/dev/mtdblock0) hasn't been an issue.
> 
> Did you erase the block in question first?
> 
> -- 
> dwmw2
> 

-- 
Paul van Gool                                               Rincon Networks
paul.vangool@rinconnetworks.com                              (805)-705-1442