Hi Mark, On Tue, 23 Dec 2025 at 01:22, Mark Brown <[email protected]> wrote: > > In order to simplify interdependencies in the rest of the series define > the feature detection for SME and it's subfeatures. Due to the need for
nit: it's -> its Reviewed-by: Fuad Tabba <[email protected]> Cheers, /fuad > vector length configuration we define a flag for SME like for SVE. We > also have two subfeatures which add architectural state, FA64 and SME2, > which are configured via the normal ID register scheme. > > Also provide helpers which check if the vCPU is in streaming mode or has > ZA enabled. > > Signed-off-by: Mark Brown <[email protected]> > --- > arch/arm64/include/asm/kvm_host.h | 35 ++++++++++++++++++++++++++++++++++- > arch/arm64/kvm/sys_regs.c | 2 +- > 2 files changed, 35 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_host.h > b/arch/arm64/include/asm/kvm_host.h > index 0f3d26467bf0..0816180dc551 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -353,6 +353,8 @@ struct kvm_arch { > #define KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS 10 > /* Unhandled SEAs are taken to userspace */ > #define KVM_ARCH_FLAG_EXIT_SEA 11 > + /* SME exposed to guest */ > +#define KVM_ARCH_FLAG_GUEST_HAS_SME 12 > unsigned long flags; > > /* VM-wide vCPU feature set */ > @@ -1062,7 +1064,16 @@ struct kvm_vcpu_arch { > #define vcpu_has_sve(vcpu) kvm_has_sve((vcpu)->kvm) > #endif > > -#define vcpu_has_vec(vcpu) vcpu_has_sve(vcpu) > +#define kvm_has_sme(kvm) (system_supports_sme() && \ > + test_bit(KVM_ARCH_FLAG_GUEST_HAS_SME, > &(kvm)->arch.flags)) > + > +#ifdef __KVM_NVHE_HYPERVISOR__ > +#define vcpu_has_sme(vcpu) kvm_has_sme(kern_hyp_va((vcpu)->kvm)) > +#else > +#define vcpu_has_sme(vcpu) kvm_has_sme((vcpu)->kvm) > +#endif > + > +#define vcpu_has_vec(vcpu) (vcpu_has_sve(vcpu) || vcpu_has_sme(vcpu)) > > #ifdef CONFIG_ARM64_PTR_AUTH > #define vcpu_has_ptrauth(vcpu) \ > @@ -1602,6 +1613,28 @@ void kvm_set_vm_id_reg(struct kvm *kvm, u32 reg, u64 > val); > #define kvm_has_sctlr2(k) \ > (kvm_has_feat((k), ID_AA64MMFR3_EL1, SCTLRX, IMP)) > > +#define kvm_has_fa64(k) \ > + (system_supports_fa64() && \ > + kvm_has_feat((k), ID_AA64SMFR0_EL1, FA64, IMP)) > + > +#define kvm_has_sme2(k) \ > + (system_supports_sme2() && \ > + kvm_has_feat((k), ID_AA64PFR1_EL1, SME, SME2)) > + > +#ifdef __KVM_NVHE_HYPERVISOR__ > +#define vcpu_has_sme2(vcpu) kvm_has_sme2(kern_hyp_va((vcpu)->kvm)) > +#define vcpu_has_fa64(vcpu) kvm_has_fa64(kern_hyp_va((vcpu)->kvm)) > +#else > +#define vcpu_has_sme2(vcpu) kvm_has_sme2((vcpu)->kvm) > +#define vcpu_has_fa64(vcpu) kvm_has_fa64((vcpu)->kvm) > +#endif > + > +#define vcpu_in_streaming_mode(vcpu) \ > + (__vcpu_sys_reg(vcpu, SVCR) & SVCR_SM_MASK) > + > +#define vcpu_za_enabled(vcpu) \ > + (__vcpu_sys_reg(vcpu, SVCR) & SVCR_ZA_MASK) > + > static inline bool kvm_arch_has_irq_bypass(void) > { > return true; > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index c8fd7c6a12a1..3576e69468db 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -1945,7 +1945,7 @@ static unsigned int sve_visibility(const struct > kvm_vcpu *vcpu, > static unsigned int sme_visibility(const struct kvm_vcpu *vcpu, > const struct sys_reg_desc *rd) > { > - if (kvm_has_feat(vcpu->kvm, ID_AA64PFR1_EL1, SME, IMP)) > + if (vcpu_has_sme(vcpu)) > return 0; > > return REG_HIDDEN; > > -- > 2.47.3 >
