Dear Simon, In message <20201019135602.3943835-12-...@chromium.org> you wrote: > In some cases it is necessary to pass parameters to Linux so that it will > boot correctly. For example, the rootdev parameter is often used to > specify the root device. However the root device may change depending on > whence U-Boot loads the kernel. At present it is necessary to build up > the command line by adding device strings to it one by one. > > It is often more convenient to provide a template for bootargs, with > U-Boot doing the substitution from other environment variables. > > Add a way to substitute strings in the bootargs variable. This allows > things like "rootdev=%U" to be used in bootargs, with the %U substitution > providing the UUID of the root device.
Argh, no, please don't. You add something unconditionally to common code which very few people need. U-Boot size is growing all the time because of such ... features. This may be acceptable on the systems you have in mind, but I consider this selfish. Why do we have to add yet another non-standard way of substituting variables in a string? Can we not use alreay existing methonds instead? Why do you have to use "%U" in your template instead of for example "${uuid}" ? Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de If you use modules, you pay the price. Sane embedded solutions running in "tight" environments don't use modules :-) -- Benjamin Herrenschmidt in <1258234866.2140.451.camel@pasglop>