[U-Boot-Users] simplify bootm command

[Wolfgang Denk]

In message <48982523.4030706 at gmail.com> you wrote:
>
> My current best thought is to create a new "boot simple" (boots? 
> bootsm?) command that contains only the essence of bootm.  I would then 
> change the command "bootm" to do a hush script run of the env variable 
> "bootm" (i.e. the command "bootm" would really just be "run bootm"). 
> The env variable "bootm" would then have to be created with the complex 
> (board/config appropriate) sequence that is currently hardcoded in the 
> command "bootm", with the last command being "boots", of course.  This 
> would be selected by a new CONFIG_ configuration so that old boards 
> would go on as is until or unless the maintainer chose to move forward.

Hm... if we go to such efforts, we might even go one step farther and
solve the problem in a more general way.

One idea that has been spinning in my mind for some time is  to  make
the  "run"  command to execute the content of an environment variable
optional. Instead, we could try and handle environment variable names
similar to command names, i. e. instead of typing "run foo; run  bar"
you  could  just  write  "foo;  bar" (I woull probably still keep the
"run" command around to allow for the implicit error handling as used
in "run foo bar" without forcing the user to use the  hush  shell  to
get the equivalent "foo && bar").

Then it's just a matter of defining the search order: if the variable
name space gets searched before the command names, we could  redefine
all builtin commands. [Probbaly the search order (variables before or
after   builtin  commands)  can  be  even  mad  selectable  using  an
environment variable :-) ].

A new "builtin" command would allow to stillr efer to the original
builtin commands.

With such an implementation, we could move the FDT  handling  into  a
command  sequence  stored  in a "bootm" environment variable, and the
last part of this variable would be "builtin bootm" to run  the  real
(simplified) command.

What do you think?

Best regards,

Wolfgang Denk

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