Boot from NAND flash ???
Charles Manning
manningc2 at actrix.gen.nz
Mon May 20 04:17:22 EDT 2002
On Thu, 13 Jan 2000 00:50, Thomas Gleixner wrote:
> On Monday, 13. May 2002 18:47, Vadim Khmelnitsky wrote:
> > [Thomas]
> > There's another important limitation. Who guarantees you, that your
> > "boot-page" does not get bad or is a bad block already. That's the
> > reason, why DOC has 4 blocks with the same code.
> >
> > [Vadim]
> > Actually, in Diskonchip Millennium 8MB we have first erasable unit
> > guaranteed to be good .
> > We do have two copies of a boot-code stored one after another in page 0
> > and 1 of the first erasable unit .
>
> That applies for DOC devices, but not for raw NAND chips.
>
> Thomas
The raw Samsung/Toshiba parts are tested and their bad blocks are marked.
They guarantee that the first block is not bad when shipped.
BTW: Some of the newer raw NAND devices power up with page 0 pre-selected for
read. Thus, you can fetch executable code directly off these devices at boot
time (ie. use them to replace boot NOR).
-- Charles
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