[PATCH 09/11] defaultenv-2: boot/net add bootp support

[Sascha Hauer]

On Sat, Sep 08, 2012 at 04:51:25PM +0200, Jean-Christophe PLAGNIOL-VILLARD wrote:
> > 
> > The current /env/boot/* scripts are written with the intention that they
> > should be simple scripts which are easily adjustable. They are also
> > meant as templates to add other board/company/project specific files.
> > 
> > Now it only takes one patch series to turn them into complex scripts
> > which after staring at them for half an hour I still not fully
> > understand. I don't understand why this must be so, because it seems
> > what the scripts do is a complex way of saying:
> > 
> > path=/mnt/tftp
> > global.bootm.image="${path}/${global.dhcp.bootfile}"
> > global.bootm.oftree="${path}/${global.dhcp.oftree_file}"
> > nfsroot="${global.dhcp.rootpath}"
> > bootargs-ip
> > bootargs-root-nfs -n "$nfsroot"
> > 
> > Since you introduced a boot sequence support it should be easy to try
> > bootp like above and fall back to the regular net boot if it fails.
> no as the the nfsroot or global.bootm.oftree or global.bootm.image
> may or may not specified via dhcp
> 
> the oftre is the perfect example you want use the one in the env if
> not specify it via dhcp and so on
> 
> This was a feature of the defaultenv that I use for long time
> I need to keep it

Look, there are so many possible setups.

- kernel on tftp, disk, nand
- oftree on tftp, disk, nand, none at all
- root on nfs, disk, nand

Even the above makes for 36 combinations, different names/partitions not
counted. The setups are board specific, company specific, project
specific or person specific. There is no way of making all happy with a
single script. Instead the bootscripts are meant as an *example* to get
started, they are *not* meant to fit all your and everyone elses needs.

You want to get your oftree path from a dhcp request? Then fine, change
global.bootm.oftree to "${path}/${global.dhcp.oftree_file}". You want
to use the one from /env/oftree? Then change global.bootm.oftree
accordingly. You want to use one as a fallback from another one? Also
fine, do some if/else.

But please don't try to force your specific setup to other people.

Sascha

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