CFI-0002 NOR flash blocking CPU on status register reads

[Jamie Lokier]

Holger Schurig wrote:
> > Won't the CPU read the initial boot instructions from this
> > flash, get programming status bytes instead of CPU
> > instructions, and thus get confused?
> 
> The bootloader could/should make sure that every block is in the 
> correct state for Linux.

Even the bootloader cannot start, if the flash is not in the correct
programming state - even though bootloader partition is not touched.

(The bootloader instructions are temporarily replaced by garbage while
programming _any_ blocks.)

However, see my other reply.  If the board's reset signal is wired to
the flash, it should force the flash into a suitable state prior to
reading the bootloader.  I have to check if they wired the reset
signal properly: these schematics have too many zero-ohm links which
might be there or not on manufactured boards.

-- Jamie