[RFC v3 05/10] target/arm: Introduce kvm_arm_cpu_feature_supported

[Peng Liang]

Introduce kvm_arm_cpu_feature_supported to check whether KVM supports to
set CPU features in ARM.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Peng Liang <liangpeng10@huawei.com>
---
 target/arm/kvm64.c   | 14 ++++++++++++++
 target/arm/kvm_arm.h |  7 +++++++
 2 files changed, 21 insertions(+)

diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 86a5bca5a4ec..5700c4084090 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -721,6 +721,20 @@ bool kvm_arm_steal_time_supported(void)
     return kvm_check_extension(kvm_state, KVM_CAP_STEAL_TIME);
 }
 
+bool kvm_arm_cpu_feature_supported(void)
+{
+    static bool cpu_feature_initialized;
+    static bool cpu_feature_supported;
+
+    if (!cpu_feature_initialized) {
+        cpu_feature_supported = kvm_check_extension(kvm_state,
+                                                    KVM_CAP_ARM_CPU_FEATURE);
+        cpu_feature_initialized = true;
+    }
+
+    return cpu_feature_supported;
+}
+
 QEMU_BUILD_BUG_ON(KVM_ARM64_SVE_VQ_MIN != 1);
 
 void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index eb81b7059eb1..a6a1df775cd2 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -308,6 +308,13 @@ bool kvm_arm_pmu_supported(void);
  */
 bool kvm_arm_sve_supported(void);
 
+/**
+ * kvm_arm_cpu_feature_supported:
+ *
+ * Returns true if KVM can set CPU features and false otherwise.
+ */
+bool kvm_arm_cpu_feature_supported(void);
+
 /**
  * kvm_arm_get_max_vm_ipa_size:
  * @ms: Machine state handle
-- 
2.26.2