[i.MX28 GPMI] problem overwriting all-0xff data in NAND

[Wolfram Sang]

> > >> I am debugging the DMA bug now. and I will send it out when i fix it.
> > >>
> > > What sort of DMA bug?
> > >
> > 
> > The DMA may time-out. :(
> > 
> > The DMA time-out may occur in two situations:
> > [1] send a command DMA descriptor, see the nfc->send_command() function.
> > [2] read the non-ecc data from nand, see the nfc->read_data() function.
> > 
> > I don't know why. Maybe caused by the timing, or something else.

I am confused. The send-command DMA timeout prevents any write for me.
You guys surely would have noticed if you have been bitten as well. Does
it depend on the NAND chip?

> Maybe you are missing this patch:
> http://lists.infradead.org/pipermail/linux-arm-kernel/2011-April/049105.html
> I sent it in April, but apparently it has not been integrated in
> mainline or the pengutronix git.

Well, just resend them; might be worth trying Shawn's comment, too (if
that reset is really needed). BTW they didn't help for my case :(

Regards,

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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