Re: [Qemu-devel] [PATCH 6/6] x86_iommu/amd: Enable Guest virtual APIC support

[Igor Mammedov <imammedo@redhat.com>]

On Tue, 11 Sep 2018 11:49:49 -0500
Brijesh Singh <brijesh.singh@amd.com> wrote:

> Now that amd-iommu support interrupt remapping, enable the GASup in IVRS
> table and GASup in extended feature register to indicate that IOMMU
> support guest virtual APIC mode.
> 
> Note that the GAMSup is set to zero to indicate that  Guest Virtual
> APIC does not support advanced interrupt features (i.e virtualized
> interrupts using the guest virtual APIC).
> 
> See Table 21 from IOMMU spec for interrupt virtualization controls
> 
> IOMMU spec: https://support.amd.com/TechDocs/48882_IOMMU.pdf
Table numbers and URLs tend to change over long time span,
pls exact spec title and revision to above info, so one could
easily google it.

> 
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Richard Henderson <rth@twiddle.net>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
> Cc: Tom Lendacky <Thomas.Lendacky@amd.com>
> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> ---
>  hw/i386/acpi-build.c | 3 ++-
>  hw/i386/amd_iommu.h  | 2 +-
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index 5c2c638..1cbc8ba 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -2565,7 +2565,8 @@ build_amd_iommu(GArray *table_data, BIOSLinker *linker)
>      build_append_int_noprefix(table_data,
>                               (48UL << 30) | /* HATS   */
>                               (48UL << 28) | /* GATS   */
> -                             (1UL << 2),    /* GTSup  */
> +                             (1UL << 2)   | /* GTSup  */
> +                             (1UL << 6),    /* GASup  */
>                               4);
>      /*
>       *   Type 1 device entry reporting all devices
> diff --git a/hw/i386/amd_iommu.h b/hw/i386/amd_iommu.h
> index 1dab974..5defaac 100644
> --- a/hw/i386/amd_iommu.h
> +++ b/hw/i386/amd_iommu.h
> @@ -177,7 +177,7 @@
>  /* extended feature support */
>  #define AMDVI_EXT_FEATURES (AMDVI_FEATURE_PREFETCH | AMDVI_FEATURE_PPR | \
>          AMDVI_FEATURE_IA | AMDVI_FEATURE_GT | AMDVI_FEATURE_HE | \
> -        AMDVI_GATS_MODE | AMDVI_HATS_MODE)
> +        AMDVI_GATS_MODE | AMDVI_HATS_MODE | AMDVI_FEATURE_GA)
>  
>  /* capabilities header */
>  #define AMDVI_CAPAB_FEATURES (AMDVI_CAPAB_FLAT_EXT | \