[cc'ing rmk and linux-arm-kernel] On Mon, Jul 12, 2010 at 7:43 PM, Stephen Rothwell <s...@canb.auug.org.au> wrote: > After this change, doing a "make xxx_defconfig" will check first for > a file called arch/<arch>/configs/Kconfig.xxx and use that to generate > the .config (effectively starting from an allnoconfig). If that file > doesn't exist, it will use arch/<ARCH>/configs/xxx_defconfig as now.
Oops, I hadn't seen this patch when I wrote mine this afternoon[1]. :-) A few minor differences, but essentially the same solution. [1] http://patchwork.ozlabs.org/patch/58823/ I chose to use -D /dev/null (defconfig from an empty file) instead of -n (allnoconfig) so that default values in Kconfig would get respected. For the benefit of everyone else, here's an excerpt from our IRC conversation this afternoon: 19:49 < gcl> sfr: [...] Your patch and my patch are essentially doing exactly the same thing, except that I used '-d' and you used '-n'. 19:50 < gcl> s/-d/-D/ 19:55 < sfr> right 19:55 < sfr> Linus wanted us to use -n 19:55 < sfr> because that way you get what you asked for, not what the defaults say ... 19:58 < gcl> I suppose we don't currently have a way to say "select FOO=n", so I suppose that makes sense 19:58 < gcl> although I think using the defaults unless told not to is a better approach in the long run 19:59 < gcl> most of the time I *don't want* to ask for something in the defconfig. :-) 20:00 < gcl> I just want TheBestOrCorrectAnswer to be chosen for me 20:04 < sfr> gcl: go read Linus' vision :-) > Signed-off-by: Stephen Rothwell <s...@canb.auug.org.au> > --- > scripts/kconfig/Makefile | 14 +++++++++++++- > 1 files changed, 13 insertions(+), 1 deletions(-) > > Hi Linus, > > Is this more the direction you want to take? > > There are still 2 main problems with is approach: > > - there are some config options that are globally and > unconditionally enabled that some platforms may not want. The only way > currently to turn them off is to reproduce the config entry with the > different default. I am not sure if we need a wa to turn them off or to > just change them to being neede to be selected by those that do want them. > - we have no way to select options that are neither bool or > tristate to suitable values. Again the only way to do that currently is > to reproduce the config entry with a different default value. For both of the above problems, what if we added syntax like the following to Kconfig? config FOO bool select BAR = n select FOO_VALUE = 54 > I am currently working towards using this to recreate the PowerPC > defconfigs, but it is a slow process as they have some much stuff enabled > in them and some of it is probably actually not relevant. If the trimmed configs are merged, then there is no rush on this. We can keep them around and switch them over as people want to make changes. > This process is made easier by the recent commit "kbuild: Warn on > selecting symbols with unmet direct dependencies" that is in the kbuild > tree (and linux-next). Ah, I didn't know that change was being merged. That indeed makes things easier, and eliminates the post-test that I do to make sure that the resulting config is actually valid. > diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile > index 7ea649d..1ab8f45 100644 > --- a/scripts/kconfig/Makefile > +++ b/scripts/kconfig/Makefile > @@ -117,9 +117,21 @@ else > $(Q)$< -D arch/$(SRCARCH)/configs/$(KBUILD_DEFCONFIG) $(Kconfig) > endif > > -%_defconfig: $(obj)/conf > +configs_dir := $(srctree)/arch/$(SRCARCH)/configs > +# We check a level of sub directories because arch/powerpc > +# has its defconfig files arranged that way > +old_defconfigs := $(patsubst $(configs_dir)/%,%,\ > + $(wildcard $(configs_dir)/*_defconfig) \ > + $(wildcard $(configs_dir)/*/*_defconfig)) > +defconfigs := $(patsubst $(configs_dir)/Kconfig.%,%_defconfig,\ > + $(wildcard $(configs_dir)/Kconfig.*)) > + Ugh. My first impression is that all this shouldn't be necessary, and it should be okay to just make the two following rules include a pattern dependency for the source file. However, as I play with it, I cannot seem to get the rules right to handle the sub directories. The $(defconfigs) patsubst at least could be done solely with dependencies on the target rule if the files were named *.Kconfig instead of Kconfig.* (because subdirectories are not handled in that case). For example: %_defconfig: $(obj)/conf arch/$(SRCARCH)/configs/%.Kconfig $(Q)$< -n arch/$(SRCARCH)/configs/$*.Kconfig > +$(old_defconfigs): %_defconfig: $(obj)/conf > $(Q)$< -D arch/$(SRCARCH)/configs/$@ $(Kconfig) > > +$(defconfigs): %_defconfig: $(obj)/conf > + $(Q)$< -n arch/$(SRCARCH)/configs/Kconfig.$* > + > # Help text used by make help > help: > �...@echo ' config - Update current config utilising a > line-oriented program' Cheers, g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
