On Wed, 13 Apr 2016, Wolfgang Denk wrote:
Dear Robert,
In message alpine.LFD.2.20.1604130835360.4548@localhost.localdomain you wrote:
(in fact, i can see that of the several vendors that have common/ directories, only ti/common/ has a Kconfig file, so i'm concluding that a common/ directory containing a Kconfig file is more the exception rather than the norm. ti/common/ seems like a special case, in that it contains just some board_detect code, and its Kconfig would be explicitly sourced by the subset of ti boards for which it's relevant, so that makes sense. but, as i mentioned, that's the only example i see.)
Kconfig stuff is still relatively new, and not many vendors update their code on a regular base, unless pressed into it ...
actually, the point i was trying to make (badly) is that almost all Kconfig files exist *outside* of vendor common/ directories, which seems to make sense, as selection is tied more to boards, while the common/ directories are treated simply as the source of code that is being selected. so it makes sense (at least to me) that vendor/ common directories will contain a Makefile and piles of selectable common code, but not a Kconfig file.
i was only noting that there is a single example -- board/ti/common/ -- that contains a Kconfig file, but that seems like a trivial case.
i suppose it might have been possible for the build process to add the common directory to the include search path for header files,
I think we tried this (many, many years ago), and it caused all kinds of problems; the vendor specific code is often... umm... vendor specific.
it took only a few more minutes to realize that adding that directory to the search path would be a really bad idea.
finally, in terms of pulling in common source files, i'm just going to be appalled by the occasional form of this:
amcc/bubinga/flash.c:#include "../common/flash.c" amcc/walnut/flash.c:#include "../common/flash.c" amcc/bamboo/flash.c:#include "../common/flash.c" amcc/luan/flash.c:#include "../common/flash.c"
I share your dislike...
or is textual inclusion of source files from a common directory acceptable practice? i normally really dislike this, but is doing that in this specific context in u-boot considered acceptable?
This is very, very old code. It would not be accepted these days. And if you look closer, the code is totally redundant, as the standard CFI driver would probably work on most of these boards - if not everywhere.
good. i'm bringing a pile of legacy u-boot code up to date and some of it does this, so i was wondering if this was some approved coding style for u-boot. i'm relieved that it isn't, so i can refactor the code and get rid of that.
onward ...
rday