[RFC,08/12] arm64: [HACK] Basic SVE support

Commit Message

Dave Martin Jan. 18, 2019, 4:14 p.m. UTC

For compatibility reasons, new vcpus created by KVM always have SVE
disabled by default.

To enable SVE to be turned on, this patch adds an option --sve.

Currently, no independent control is added per-vcpu.  This means
that it is not currently possible to create a VM containing a mix
of SVE-enabled and non-SVE-enabled vcpus.  This functionality could
be added later if desired.

Signed-off-by: Dave Martin <[e-mail]>
---
 arm/aarch64/include/kvm/kvm-config-arch.h | 2 ++
 arm/aarch64/include/kvm/kvm-cpu-arch.h    | 3 ++-
 arm/include/arm-common/kvm-config-arch.h  | 1 +
 3 files changed, 5 insertions(+), 1 deletion(-)

Patch

diff --git a/arm/aarch64/include/kvm/kvm-config-arch.h b/arm/aarch64/include/kvm/kvm-config-arch.h
index cb3f8bc..7710f14 100644
--- a/arm/aarch64/include/kvm/kvm-config-arch.h
+++ b/arm/aarch64/include/kvm/kvm-config-arch.h
@@ -6,6 +6,8 @@ 
 			"Run AArch32 guest"),				\
 	OPT_BOOLEAN('\0', "pmu", &(cfg)->has_pmuv3,			\
 			"Create PMUv3 device"),				\
+	OPT_BOOLEAN('\0', "sve", &(cfg)->has_sve,			\
+		    "Enable SVE for the guest"),			\
 	OPT_BOOLEAN('\0', "show-reg-list", &(cfg)->show_reg_list,	\
 		    "Show the list of KVM register IDs on startup"),	\
 	OPT_U64('\0', "kaslr-seed", &(cfg)->kaslr_seed,			\
diff --git a/arm/aarch64/include/kvm/kvm-cpu-arch.h b/arm/aarch64/include/kvm/kvm-cpu-arch.h
index a9d8563..6aeddde 100644
--- a/arm/aarch64/include/kvm/kvm-cpu-arch.h
+++ b/arm/aarch64/include/kvm/kvm-cpu-arch.h
@@ -8,7 +8,8 @@ 
 #define ARM_VCPU_FEATURE_FLAGS(kvm, cpuid)	{				\
 	[0] = ((!!(cpuid) << KVM_ARM_VCPU_POWER_OFF) |				\
 	       (!!(kvm)->cfg.arch.aarch32_guest << KVM_ARM_VCPU_EL1_32BIT) |	\
-	       (!!(kvm)->cfg.arch.has_pmuv3 << KVM_ARM_VCPU_PMU_V3))		\
+	       (!!(kvm)->cfg.arch.has_pmuv3 << KVM_ARM_VCPU_PMU_V3) |		\
+	       (!!(kvm)->cfg.arch.has_sve << KVM_ARM_VCPU_SVE))			\
 }
 
 #define ARM_MPIDR_HWID_BITMASK	0xFF00FFFFFFUL
diff --git a/arm/include/arm-common/kvm-config-arch.h b/arm/include/arm-common/kvm-config-arch.h
index f18bfd4..6abb170 100644
--- a/arm/include/arm-common/kvm-config-arch.h
+++ b/arm/include/arm-common/kvm-config-arch.h
@@ -9,6 +9,7 @@  struct kvm_config_arch {
 	bool		virtio_trans_pci;
 	bool		aarch32_guest;
 	bool		has_pmuv3;
+	bool		has_sve;
 	bool		show_reg_list;
 	u64		kaslr_seed;
 	enum irqchip_type irqchip;