[U-Boot] Dual boot Images in Flash

[Wolfgang Denk]

Dear pshambhu,

In message <1380547665536-164381.post at n7.nabble.com> you wrote:
> 
> As per previous posting i got to know that, there will be only one reset
> entry point, can't i have the another entry point in it.

You can talk to your chip vendor to provide you with some kind of
logic to detect failed boot attempts and provide an alternative reset
vecotr then.  Guess your chances to gett that are extremely small,
though.

You can, of course, throw hardware at it, and for example provide
duplicate storage . memory devices for booting from, so you only have
to swap chip select resp. address lines to select the alternative boot
device.

>   -  Why i can't have multiple entry points ? and what will be effect if i
> introduced ? 

You can't, because your processor only has one.

>   -  Where the reset entry points are defined in the u-boot code ?

They are not defined in U-Boot, they are defined in the processor
silicon or ROM code.

Disclaimer: of course things get even more complicated when you keep
in mind that there is a multiverse of different hardware solutions,
some of them with special, and others with truely exotic features.

Best regards,

Wolfgang Denk

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