Re: [Qemu-devel] [PATCH RFC 2/2] s390x/cpumodel: allow zpci features in qemu model

[Cornelia Huck <cohuck@redhat.com>]

On Tue, 30 Jan 2018 14:09:43 +0100
David Hildenbrand <david@redhat.com> wrote:

> On 29.01.2018 17:52, Cornelia Huck wrote:
> > AEN can be provided unconditionally, ZPCI has to be turned on
> > manually (it should really depend on CONFIG_PCI).

I think we should keep it non-default even with your suggested change.

> > 
> > With -cpu qemu,zpci=on, a 4.15 guest kernel can now successfully
> > detect virtio-pci devices under tcg.
> > 
> > Signed-off-by: Cornelia Huck <cohuck@redhat.com>
> > ---
> >  target/s390x/gen-features.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
> > index 0570f597ec..db7ac965a0 100644
> > --- a/target/s390x/gen-features.c
> > +++ b/target/s390x/gen-features.c
> > @@ -574,6 +574,7 @@ static uint16_t qemu_LATEST[] = {
> >      S390_FEAT_INTERLOCKED_ACCESS_2,
> >      S390_FEAT_MSA_EXT_4,
> >      S390_FEAT_MSA_EXT_3,
> > +    S390_FEAT_ADAPTER_EVENT_NOTIFICATION,
> >  };
> >  
> >  /* add all new definitions before this point */
> > @@ -582,6 +583,8 @@ static uint16_t qemu_MAX[] = {
> >      S390_FEAT_STFLE_53,
> >      /* generates a dependency warning, leave it out for now */
> >      S390_FEAT_MSA_EXT_5,
> > +    /* should be conditional on CONFIG_PCI */
> > +    S390_FEAT_ZPCI,
> >  };
> >    
> 
> What about something in addition like that, should work for now
> 
> diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
> index 212a5f0697..62fc8d538d 100644
> --- a/target/s390x/cpu_models.c
> +++ b/target/s390x/cpu_models.c
> @@ -23,6 +23,7 @@
>  #include "qapi/qmp/qbool.h"
>  #ifndef CONFIG_USER_ONLY
>  #include "sysemu/arch_init.h"
> +#include "hw/pci/pci.h"
>  #endif
> 
>  #define CPUDEF_INIT(_type, _gen, _ec_ga, _mha_pow, _hmfai, _name, _desc) \
> @@ -1271,6 +1272,12 @@ static void register_types(void)
> 
>      /* init all bitmaps from gnerated data initially */
>      s390_init_feat_bitmap(qemu_max_cpu_feat_init, qemu_max_cpu_feat);
> +#ifndef CONFIG_USER_ONLY
> +    if (!pci_available) {
> +        clear_bit(S390_FEAT_ZPCI, qemu_max_cpu_feat);
> +    }
> +#endif
> +
>      for (i = 0; i < ARRAY_SIZE(s390_cpu_defs); i++) {
>          s390_init_feat_bitmap(s390_cpu_defs[i].base_init,
>                                s390_cpu_defs[i].base_feat);
> 
> 

That makes sense, added. Thanks!

> 
> >  /****** END FEATURE DEFS ******/
> >   
> 
>