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Message-ID: <27c5a295-8bb0-f6b2-bafe-9900e28403a7@linux.ibm.com>
Date:   Wed, 19 Jan 2022 14:39:57 +0100
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Subject: Re: [PATCH v2 29/30] KVM: s390: introduce CPU feature for zPCI
 Interpretation
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To:     Matthew Rosato <mjrosato@linux.ibm.com>, linux-s390@vger.kernel.org
Cc:     alex.williamson@redhat.com, cohuck@redhat.com,
        schnelle@linux.ibm.com, farman@linux.ibm.com,
        borntraeger@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com,
        gerald.schaefer@linux.ibm.com, agordeev@linux.ibm.com,
        frankja@linux.ibm.com, david@redhat.com, imbrenda@linux.ibm.com,
        vneethv@linux.ibm.com, oberpar@linux.ibm.com, freude@linux.ibm.com,
        thuth@redhat.com, pasic@linux.ibm.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20220114203145.242984-1-mjrosato@linux.ibm.com>
 <20220114203145.242984-30-mjrosato@linux.ibm.com>
From:   Pierre Morel <pmorel@linux.ibm.com>
In-Reply-To: <20220114203145.242984-30-mjrosato@linux.ibm.com>
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On 1/14/22 21:31, Matthew Rosato wrote:
> KVM_S390_VM_CPU_FEAT_ZPCI_INTERP relays whether zPCI interpretive
> execution is possible based on the available hardware facilities.
> 
> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
> ---
>   arch/s390/include/uapi/asm/kvm.h | 1 +
>   arch/s390/kvm/kvm-s390.c         | 4 ++++
>   2 files changed, 5 insertions(+)
> 
> diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
> index 7a6b14874d65..ed06458a871f 100644
> --- a/arch/s390/include/uapi/asm/kvm.h
> +++ b/arch/s390/include/uapi/asm/kvm.h
> @@ -130,6 +130,7 @@ struct kvm_s390_vm_cpu_machine {
>   #define KVM_S390_VM_CPU_FEAT_PFMFI	11
>   #define KVM_S390_VM_CPU_FEAT_SIGPIF	12
>   #define KVM_S390_VM_CPU_FEAT_KSS	13
> +#define KVM_S390_VM_CPU_FEAT_ZPCI_INTERP 14
>   struct kvm_s390_vm_cpu_feat {
>   	__u64 feat[16];
>   };
> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> index b6c32fc3b272..3ed59fe512dd 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -434,6 +434,10 @@ static void kvm_s390_cpu_feat_init(void)
>   	if (test_facility(151)) /* DFLTCC */
>   		__insn32_query(INSN_DFLTCC, kvm_s390_available_subfunc.dfltcc);
>   
> +	if (test_facility(69) && test_facility(70) && test_facility(71) &&
> +	    test_facility(72)) /* zPCI Interpretation */
> +		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ZPCI_INTERP);
> +

Don't we want to start the support of ZPCI interpretation starting with 
Z14 ?

>   	if (MACHINE_HAS_ESOP)
>   		allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);
>   	/*
> 

-- 
Pierre Morel
IBM Lab Boeblingen