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From:   Mathieu Malaterre <malat@debian.org>
Date:   Wed, 13 Mar 2019 21:17:37 +0100
Message-ID: <CA+7wUsxruu0GdyRGJ3vsjRvSBAptMn8_f5BmeMo=-E3zbhGGxQ@mail.gmail.com>
Subject: Re: [PATCH] powerpc: use $(origin ARCH) to select KBUILD_DEFCONFIG
To:     Michael Ellerman <mpe@ellerman.id.au>
Cc:     Masahiro Yamada <yamada.masahiro@socionext.com>,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        Paul Mackerras <paulus@samba.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Sat, Feb 16, 2019 at 3:26 AM Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> On Sat, Feb 16, 2019 at 1:11 AM Mathieu Malaterre <malat@debian.org> wrote:
> >
> > On Fri, Feb 15, 2019 at 10:41 AM Masahiro Yamada
> > <yamada.masahiro@socionext.com> wrote:
> > >
> > > I often test all Kconfig commands for all architectures. To ease my
> > > workflow, I want 'make defconfig' at least working without any cross
> > > compiler.
> > >
> > > Currently, arch/powerpc/Makefile checks CROSS_COMPILE to decide the
> > > default defconfig source.
> > >
> > > If CROSS_COMPILE is unset, it is likely to be the native build, so
> > > 'uname -m' is useful to choose the defconfig. If CROSS_COMPILE is set,
> > > the user is cross-building (i.e. 'uname -m' is probably x86_64), so
> > > it falls back to ppc64_defconfig. Yup, make sense.
> > >
> > > However, I want to run 'make ARCH=* defconfig' without setting
> > > CROSS_COMPILE for each architecture.
> > >
> > > My suggestion is to check $(origin ARCH).
> > >
> > > When you cross-compile the kernel, you need to set ARCH from your
> > > environment or from the command line.
> > >
> > > For the native build, you do not need to set ARCH. The default in
> > > the top Makefile is used:
> > >
> > >   ARCH            ?= $(SUBARCH)
> > >
> > > Hence, $(origin ARCH) returns 'file'.
> > >
> > > Before this commit, 'make ARCH=powerpc defconfig' failed:
> >
> > In case you have not seen it, please check:
> >
> > http://patchwork.ozlabs.org/patch/1037835/
>
>
> I did not know that because I do not subscribe to ppc ML.
>
>
> Michael's patch looks good to me.

OK

>
> If you mimic x86, the following will work:
>

Nice! Michael do you have a preference ?

>
>
> diff --git a/Makefile b/Makefile
> index 86cf35d..eb9552d 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -356,6 +356,11 @@ ifeq ($(ARCH),sh64)
>         SRCARCH := sh
>  endif
>
> +# Additional ARCH settings for powerpc
> +ifneq ($(filter ppc%,$(ARCH)),)
> +       SRCARCH := powerpc
> +endif
> +
>  KCONFIG_CONFIG ?= .config
>  export KCONFIG_CONFIG
>
> diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
> index 488c9ed..ff01fef 100644
> --- a/arch/powerpc/Makefile
> +++ b/arch/powerpc/Makefile
> @@ -34,10 +34,10 @@ ifdef CONFIG_PPC_BOOK3S_32
>  KBUILD_CFLAGS          += -mcpu=powerpc
>  endif
>
> -ifeq ($(CROSS_COMPILE),)
> -KBUILD_DEFCONFIG := $(shell uname -m)_defconfig
> -else
> +ifeq ($(ARCH),powerpc)
>  KBUILD_DEFCONFIG := ppc64_defconfig
> +else
> +KBUILD_DEFCONFIG := $(ARCH)_defconfig
>  endif
>
>  ifdef CONFIG_PPC64
> diff --git a/scripts/subarch.include b/scripts/subarch.include
> index 6506828..c98323f 100644
> --- a/scripts/subarch.include
> +++ b/scripts/subarch.include
> @@ -8,6 +8,6 @@ SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e
> s/x86_64/x86/ \
>                                   -e s/sun4u/sparc64/ \
>                                   -e s/arm.*/arm/ -e s/sa110/arm/ \
>                                   -e s/s390x/s390/ -e s/parisc64/parisc/ \
> -                                 -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
> +                                 -e s/mips.*/mips/ \
>                                   -e s/sh[234].*/sh/ -e s/aarch64.*/arm64/ \
>                                   -e s/riscv.*/riscv/)
>
>
>
>
>
>
>
>
> --
> Best Regards
> Masahiro Yamada