Re: [PATCH v1 1/5] meson: Introduce target-specific Kconfig

[Thomas Huth]

On 06/07/2021 14.47, Philippe Mathieu-Daudé wrote:
> On 7/6/21 12:52 PM, Thomas Huth wrote:
> > On 21/06/2021 17.21, Alex Bennée wrote:
> > > From: Philippe Mathieu-Daudé <f4bug@amsat.org>
> > >
> > > Add a target-specific Kconfig. We need the definitions in Kconfig so
> > > the minikconf tool can verify they exit. However CONFIG_FOO is only
> >
> > s/exit/exist/ ?
> >
> > > enabled for target foo via the meson.build rules.
> > >
> > > Two architecture have a particularity, ARM and MIPS:
> > > their 64-bit version include the 32-bit subset.
> >
> > Why do you mention these here, but not x86, Sparc, PPC and RISC-V which
> > also have 32-bit and 64-bit variants?
>
> Because we consider them as different targets, they don't include
> (kselect) the subset.

And why is that done this way? There is certainly a big difference between 
Sparc and Sparc64, but for x86 and PPC, the 64-bit variant is a superset of 
the 32-bit variant, so why is it done different here compared to ARM and MIPS?

 Thomas


> > The patch itself looks fine to me, so once you've clarified the commit
> > message:
> >
> > Reviewed-by: Thomas Huth <thuth@redhat.com>
> >
> >
> > > Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> > > Message-Id: <20210131111316.232778-6-f4bug@amsat.org>
> > > Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
> > >
> > > ---
> > > vajb:
> > >     - removed targets that no longer exist
> > >     - reword commit message to show why we need the Kconfigs
> > > ---
>
> > > diff --git a/target/arm/Kconfig b/target/arm/Kconfig
> > > new file mode 100644
> > > index 0000000000..3f3394a22b
> > > --- /dev/null
> > > +++ b/target/arm/Kconfig
> > > @@ -0,0 +1,6 @@
> > > +config ARM
> > > +    bool
> > > +
> > > +config AARCH64
> > > +    bool
> > > +    select ARM
>
> > > diff --git a/target/mips/Kconfig b/target/mips/Kconfig
> > > new file mode 100644
> > > index 0000000000..6adf145354
> > > --- /dev/null
> > > +++ b/target/mips/Kconfig
> > > @@ -0,0 +1,6 @@
> > > +config MIPS
> > > +    bool
> > > +
> > > +config MIPS64
> > > +    bool
> > > +    select MIPS