[PATCH] [MTD][OneNAND] Multi Level Chip (MLC) OneNAND support

[Kyungmin Park]

On Wed, Apr 23, 2008 at 10:33 AM, David Woodhouse <dwmw2 at infradead.org> wrote:
> On Wed, 2008-04-23 at 09:49 +0900, Kyungmin Park wrote:
>  > On Wed, Apr 23, 2008 at 12:06 AM, David Woodhouse <dwmw2 at infradead.org> wrote:
>  > > On Thu, 2008-01-03 at 09:03 +0900, Kyungmin Park wrote:
>  > >  > This patch enables the MLC OneNAND support
>  > >  > Now it's basic support. We need to work more.
>  > >  >
>  > >  > In MLC, we use the 4KiB BufferRam instead of 2KiB.
>  > >  > With this reason it is changed to read/write data from/to BufferRAM 0 and
>  > >  > we can't use read-while-load.
>  > >  >
>  > >  > It passed the nand-tests module and it diffed against the OneNAND MTD tree instead of MTD one.
>  > >
>  > >  Did you intend this to be merged?
>  > >
>  >
>  > Yes, Before merge this one
>  > Another patch should be merged first.
>  >
>  > "[JFFS2] JFFS2 doesn't use OOB at MLC NAND/OneNAND"
>  > http://patchwork.ozlabs.org/linux-mtd/patch?id=16536
>
>  Hm, yeah... that was the other thing I wanted to ask you about.
>
>  I'm really not wonderfully happy with it. Have we done any powerfail
>  testing with MLC chips?

Now OneNAND try to solve the MLC Power Off Recovery (POR) handling at
hardware level exactly chip level.
I'm sorry since the Spec. is not open, I can't tell you more detailed
information. However, the Spec. is open, you can find it. When? I'm
not sure...

>
>  Maybe it would be better to just refuse to mount, until/unless we have a
>  proper solution?
>
Reasonable. how about to change into read-only mode? powerfail is only
occurs at write operation so read-only mode doesn't affect this
problem.

Okay, wait until we have a proper solution.

Thank you,
Kyungmin Park