Re: [OE-core] [PATCH 2/2] linux-yocto: Autoload sound driver on QEMU x86

[Mark Jonas <toertel@gmail.com>]

Hi Bruce,

On Wed, Jan 4, 2023 at 5:07 PM Bruce Ashfield <bruce.ashfield@gmail.com> wrote:
>
> On Wed, Jan 4, 2023 at 7:18 AM Mark Jonas <toertel@gmail.com> wrote:
> >
> > From: Mark Jonas <toertel@gmail.com>
> >
> > If DISTRO_FEATURES includes ALSA then automatically load the
> > snd-intel8x0 kernel module on qemux86 and qemux86-64. This matches the
> > machine configurations conf/machine/qemux86.conf and qemux86-64.conf.
> >
> > Signed-off-by: Mark Jonas <toertel@gmail.com>
> > ---
> >  meta/recipes-kernel/linux/linux-yocto.inc | 5 +++++
> >  1 file changed, 5 insertions(+)
> >
> > diff --git a/meta/recipes-kernel/linux/linux-yocto.inc b/meta/recipes-kernel/linux/linux-yocto.inc
> > index 091003ed82..c8a9b0a1e3 100644
> > --- a/meta/recipes-kernel/linux/linux-yocto.inc
> > +++ b/meta/recipes-kernel/linux/linux-yocto.inc
> > @@ -37,6 +37,11 @@ KERNEL_FEATURES:append = " ${@bb.utils.contains('MACHINE_FEATURES', 'efi', 'cfg/
> >  KERNEL_FEATURES:append = " ${@bb.utils.contains('MACHINE_FEATURES', 'numa', 'features/numa/numa.scc', '', d)}"
> >  KERNEL_FEATURES:append = " ${@bb.utils.contains('MACHINE_FEATURES', 'vfat', 'cfg/fs/vfat.scc', '', d)}"
> >
> > +# sound driver recommended by conf/machine/qemux86*.conf
> > +ALSA_MODULES = "${@bb.utils.contains("DISTRO_FEATURES", "alsa", "snd-intel8x0", "", d)}"
> > +KERNEL_MODULE_AUTOLOAD:qemux86 += "${ALSA_MODULES}"
> > +KERNEL_MODULE_AUTOLOAD:qemux86-64 += "${ALSA_MODULES}"
>
> This gets us most of the way, but if we are going to do this we should
> complete the job.
>
> We really need to make sure there's a configuration fragment that
> explicitly enables
> the modules we need (and not count on defaults, or other selects). That would go
> into the kernel-cache.
>
> It would then be something we'd add to the KERNEL_FEATRES triggered off the
> distro feature. Just like we are doing with numa and vfat that is visible in the
> context of the patch.

In my understanding this is already the case. See for example
linux-yocto_5.19.bb which contains the following lines.

KERNEL_FEATURES:append:qemux86=" cfg/sound.scc cfg/paravirt_kvm.scc"
KERNEL_FEATURES:append:qemux86-64=" cfg/sound.scc cfg/paravirt_kvm.scc"

Does that maybe mean I should better add the KERNEL_MODULE_AUTOLOAD
into the same file where the corresponding configuration fragment is
added? But that would mean to duplicate the lines over five recipes.

Alternatively I could move the cfg/sound.scc out of the recipes into
the linux-yocto.inc. But then linux-yocto-tiny_*.bb recipes would also
get it.

Cheers,
Mark