Can mtd partition span multiple devices
John Burch
jburch at vincisystems.com
Thu Apr 3 10:36:54 EST 2003
>
> On Thu, 2003-04-03 at 12:15, Kenneth Johansson wrote:
> > On Thu, 2003-04-03 at 02:58, Thomas Gleixner wrote:
> > > On Thursday 03 April 2003 00:56, John Burch wrote:
> > > > I'm wondering if a single mtd partition can span more than one
> > > > physical flash device. For example, if two flash
> devices span the
> > > > following address ranges, 0x0-0x3FFFFF and
> 0x400000-0x7FFFFF, can
> > > > an mtd partition be defined as follows?
> > > >
> > > > Name: spanning_partition
> > > > Size: 0x200000
> > > > Offset: 0x300000
> > > >
> > > > So this partition would span physical addresses 0x300000 -
> > > > 0x3FFFFF (device 1) and 0x400000 - 0x4FFFFF (device 2).
> > >
> > > Enable MTD concatenating support.
> > >
> >
> > You mean MTD partitioning no need for concatenating with
> this layout.
>
> Probably true -- if the two physical devices are laid out
> such that a single chip probe will find them together, they
> can be used as a single MTD device even without mtdconcat
> just by setting your map to cover the whole range 0->8M. You
> only really need mtdconcat for more complicated setups.
>
I'm using 2.4.17 and I don't think mtdconcat is part of that kernel
(though I may not need it anyway based on dwmw2's response). Are the
changes since then substantial, and can 2.4.17 be patched to support the
latest mtd/jffs2 code?
Second, you imply that a single chip probe will handle multiple devices
(assuming contiguous addressing?). Is this supported in 2.4.17 and is
it a common approach to use for multiple devices?
John
More information about the linux-mtd
mailing list