Re: [PATCH v4] xen/arm: Allow QEMU platform to be built with GICv2

[Dongjiu Geng <gengdongjiu1@xxxxxxxxx>]

Bertrand Marquis <Bertrand.Marquis@xxxxxxx> 于2022年1月17日周一 17:00写道：
>
> Hi,
>
> > On 17 Jan 2022, at 06:40, Dongjiu Geng <gengdongjiu1@xxxxxxxxx> wrote:
> >
> > It turns out that QEMU has been supporting GICv2 virtualization since
> > v3.1.0. So remove the dependencies on GICv3. If we want to use GICv3,
> > we can select the QEMU_LEGACY configuration.
>
> I am bit puzzled by this change introducing a legacy option actually 
> selecting the newest GIC interface.
>
> Can’t we do the opposite and introduce a QEMU_GICV2 instead ?
>
> Also why do we need to remove gic-v3 support ? The code should actually 
> select which gic to use depending on the device tree.

QEMU platfrom only select GICv3,  so I remove this limitation,  let
user or developer selects gic version is better.

>
> Regards
> Bertrand
>
> >
> > Signed-off-by: Dongjiu Geng <gengdongjiu1@xxxxxxxxx>
> > ---
> > xen/arch/arm/platforms/Kconfig | 10 +++++++++-
> > 1 file changed, 9 insertions(+), 1 deletion(-)
> >
> > diff --git a/xen/arch/arm/platforms/Kconfig b/xen/arch/arm/platforms/Kconfig
> > index c93a6b2756..41e82a42ee 100644
> > --- a/xen/arch/arm/platforms/Kconfig
> > +++ b/xen/arch/arm/platforms/Kconfig
> > @@ -13,7 +13,15 @@ config ALL_PLAT
> >       automatically select any of the related drivers.
> >
> > config QEMU
> > -     bool "QEMU aarch virt machine support"
> > +     bool "QEMU aarch virt machine support >= v3.1.0"
> > +     depends on ARM_64
> > +     select HAS_PL011
> > +     ---help---
> > +     Enable all the required drivers for QEMU aarch64 virt emulated
> > +     machine.
> > +
> > +config QEMU_LEGACY
> > +     bool "QEMU aarch virt machine support < v3.1.0"
> >       depends on ARM_64
> >       select GICV3
> >       select HAS_PL011
> > --
> > 2.25.1
> >
>