Issue : jffs2 and ecc layout

[Ghorai, Sukumar]

> -----Original Message-----
> From: Vimal Singh [mailto:vimal.newwork at gmail.com]
> Sent: Thursday, October 07, 2010 11:02 PM
> To: Ghorai, Sukumar
> Cc: linux-mtd at lists.infradead.org; linux-omap at vger.kernel.org
> Subject: Re: Issue : jffs2 and ecc layout
> 
> On Mon, Oct 4, 2010 at 12:59 PM, Ghorai, Sukumar <s-ghorai at ti.com> wrote:
> >
> >
> >> -----Original Message-----
> >> From: linux-omap-owner at vger.kernel.org [mailto:linux-omap-
> >> owner at vger.kernel.org] On Behalf Of Ghorai, Sukumar
> >> Sent: Tuesday, September 28, 2010 6:17 PM
> >> To: linux-mtd at lists.infradead.org
> >> Cc: linux-omap at vger.kernel.org
> >> Subject: Issue : jffs2 and ecc layout
> >>
> >> Hi,
> >> I was using the following ecc layout which is not working to mount the
> >> jffs2 File-system. I was in 2.6.32 kernel and working; but same layout
> is
> >> not working with latest 2.6 kernel.
> >>
> >> Observation is that - no read request issued to the driver (say
> omap2.c).
> >>
> >> # mount -t jffs2 /dev/mtdblock4 /mnt/nand
> >> [   32.505218] cannot read OOB for EB at 00000000, requested 8 bytes,
> read
> >> 0 bytes, error -22
> >> mount: Mounting /dev/mtdblock4 on /mnt/nand failed: Input/output error
> >>
> >> # dmesg
> >> <3>[   32.505218] cannot read OOB for EB at 00000000, requested 8 bytes,
> >> read 0 bytes, error -22
> >>
> I do not think above issue has anything to do with the ECC layout.
> But as I earlier pointed (in [1]), this change [2] has messed up
> function 'omap_hwcontrol'.
[Ghorai] in that case how other layout is working? Say storing the ecc at end of the spare area is working.

> All read/write functions read/write data from/to address
> info->nand.IO_ADDR_(R/W), which is not set by new function
> 'gpmc_nand_write' (which still take care of writing address/cmd to
> write registers). But since above pointer is not set (hence points to
> address '0'), driver tries to read data from wrong location.
[Ghorai] you can see following two line in _probe() function
info->nand.IO_ADDR_R = ioremap(info->phys_base, NAND_IO_SIZE);
info->nand.IO_ADDR_W = info->nand.IO_ADDR_R;

> 
> In fact, I would even suggest to try dumping nand command registers(or
> use T32) and verify if commands issued were written correctly to
> appropriate registers.
[Ghorai] I mentioned read request does not come to driver.

> 
> 
> 
> [1]: http://marc.info/?l=linux-omap&m=128302624528822&w=2
> [2] commit: http://git.infradead.org/mtd-
> 2.6.git/commitdiff/2c01946c6b9ebaa5a89710bc42ca224a7f52f227
> 
> --
> Regards,
> Vimal Singh