Boot from NAND flash ???

[Thomas Gleixner]

On Monday, 13. May 2002 12:11, Charles Manning wrote:

> There are however two mechanisms to get around this:
> * Some people and micros implement a "data pump" state machine to extract
> an executable sequence from a NAND device.
> * Some of the newer NAND devices can be accessed directly from the bus and
> can do the job of a boot ROM.
>
> There is however a limitation to both of these. The NAND can only be
> accessed sequentially (it is not random access like NOR) which limits the
> types of instruction the boot code can perform. In particular it can't
> branch or fetch from elsewhere in ROM.

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. 

-- 
Thomas
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