[U-Boot-Users] New commands

Leonid Leonid at a-k-a.net
Wed May 16 19:02:03 CEST 2007


On Wednesday, May 16, 2007 5:26 AM Wolfgang Denk:
> > Because command identification are 64bit value and U-BOOT has 63 
> > commands now. 
> > We need extend unsigned long long value.

> Unfortunately the C standard does not define any longer integer data
> types that can be used directly in the C preprocessor.

> > What proper solution is?

> Get rid of the existing coee and come up with a completely new
> implementation. But this is a non-trivial task.

There is actually an approach in place, virtually converting single
u-boot command into root of command tree. See for example how "nand"
command (or shall I say "nand" tree?) is implemented. Wolfgang, do you
approve this way of doing or it had sneaked into u-boot "illegally"?

Of course, this is only half-solution which can provide temporary
relief. As a matter of fact, I'm using it myself for my proprietary
commands.

In my mind, there are two (not mutually excluding) generic ways to
proceed (backward compatibility will be preserved of course meaning old
scripts will be still working).

1) Strictly hierarchical "CISCO-like" CLI instead of "flat" u-boot
scheme. There are several existing implementations of such CLI which can
be used.

2) Further advance of "bash"-like shell (hush is used in u-boot right
now). Existing shell lacks many features one is used to see in
Linux/Unix shells. It's highly questionable though whether it makes
sense to add u-boot specific commands in there, making u-boot shell
scripts incompatible with Linux ones. 

Best regards,

Leonid.




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