[PATCH V4] arm64: KVM: Support X-Gene guest VCPU on APM X-Gene host

[Anup Patel]

On Mon, Jul 22, 2013 at 11:01 AM, Anup Patel <anup.patel at linaro.org> wrote:
> This patch allows us to have X-Gene guest VCPU when using KVM arm64
> on APM X-Gene host.
>
> We add KVM_ARM_TARGET_XGENE_POTENZA for X-Gene Potenza compatible
> guest VCPU and we return KVM_ARM_TARGET_XGENE_POTENZA in kvm_target_cpu()
> when running on X-Gene host with Potenza core.
>
> V4:
>  - Remove default case from switch statments in kvm_target_cpu()
>
> V3:
>  - Reduce multiple "return -EINVAL" in kvm_target_cpu()
>
> V2:
>  - Renamed KVM_ARM_TARGET_XGENE_V8 to KVM_ARM_TARGET_XGENE_POTENZA
>
> V1:
>  - Initial patch with target named as KVM_ARM_TARGET_XGENE_V8
>
> Signed-off-by: Anup Patel <anup.patel at linaro.org>
> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar at linaro.org>
> ---
>  arch/arm64/include/uapi/asm/kvm.h    |    3 ++-
>  arch/arm64/kvm/guest.c               |   32 +++++++++++++++++++-------------
>  arch/arm64/kvm/sys_regs_generic_v8.c |    3 +++
>  3 files changed, 24 insertions(+), 14 deletions(-)
>
> diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
> index 5031f42..d9f026b 100644
> --- a/arch/arm64/include/uapi/asm/kvm.h
> +++ b/arch/arm64/include/uapi/asm/kvm.h
> @@ -55,8 +55,9 @@ struct kvm_regs {
>  #define KVM_ARM_TARGET_AEM_V8          0
>  #define KVM_ARM_TARGET_FOUNDATION_V8   1
>  #define KVM_ARM_TARGET_CORTEX_A57      2
> +#define KVM_ARM_TARGET_XGENE_POTENZA   3
>
> -#define KVM_ARM_NUM_TARGETS            3
> +#define KVM_ARM_NUM_TARGETS            4
>
>  /* KVM_ARM_SET_DEVICE_ADDR ioctl id encoding */
>  #define KVM_ARM_DEVICE_TYPE_SHIFT      0
> diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
> index 2c3ff67..d7bf7d6 100644
> --- a/arch/arm64/kvm/guest.c
> +++ b/arch/arm64/kvm/guest.c
> @@ -207,20 +207,26 @@ int __attribute_const__ kvm_target_cpu(void)
>         unsigned long implementor = read_cpuid_implementor();
>         unsigned long part_number = read_cpuid_part_number();
>
> -       if (implementor != ARM_CPU_IMP_ARM)
> -               return -EINVAL;
> +       switch (implementor) {
> +       case ARM_CPU_IMP_ARM:
> +               switch (part_number) {
> +               case ARM_CPU_PART_AEM_V8:
> +                       return KVM_ARM_TARGET_AEM_V8;
> +               case ARM_CPU_PART_FOUNDATION:
> +                       return KVM_ARM_TARGET_FOUNDATION_V8;
> +               case ARM_CPU_PART_CORTEX_A57:
> +                       return KVM_ARM_TARGET_CORTEX_A57;
> +               };
> +               break;
> +       case ARM_CPU_IMP_APM:
> +               switch (part_number) {
> +               case APM_CPU_PART_POTENZA:
> +                       return KVM_ARM_TARGET_XGENE_POTENZA;
> +               };
> +               break;
> +       };
>
> -       switch (part_number) {
> -       case ARM_CPU_PART_AEM_V8:
> -               return KVM_ARM_TARGET_AEM_V8;
> -       case ARM_CPU_PART_FOUNDATION:
> -               return KVM_ARM_TARGET_FOUNDATION_V8;
> -       case ARM_CPU_PART_CORTEX_A57:
> -               /* Currently handled by the generic backend */
> -               return KVM_ARM_TARGET_CORTEX_A57;
> -       default:
> -               return -EINVAL;
> -       }
> +       return -EINVAL;
>  }
>
>  int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
> diff --git a/arch/arm64/kvm/sys_regs_generic_v8.c b/arch/arm64/kvm/sys_regs_generic_v8.c
> index 4268ab9..8fe6f76 100644
> --- a/arch/arm64/kvm/sys_regs_generic_v8.c
> +++ b/arch/arm64/kvm/sys_regs_generic_v8.c
> @@ -90,6 +90,9 @@ static int __init sys_reg_genericv8_init(void)
>                                           &genericv8_target_table);
>         kvm_register_target_sys_reg_table(KVM_ARM_TARGET_CORTEX_A57,
>                                           &genericv8_target_table);
> +       kvm_register_target_sys_reg_table(KVM_ARM_TARGET_XGENE_POTENZA,
> +                                         &genericv8_target_table);
> +
>         return 0;
>  }
>  late_initcall(sys_reg_genericv8_init);
> --
> 1.7.9.5
>
> _______________________________________________
> kvmarm mailing list
> kvmarm at lists.cs.columbia.edu
> https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm

Hi Marc,

Do you think more changes are required to this patch ?

Regards,
Anup