[RFC PATCH 3/5] target/arm/kvm: add helper to detect EL2 when using KVM

[Miguel Luis]

From: Haibo Xu <haibo.xu@linaro.org>

Introduce query support for KVM_CAP_ARM_EL2.

Ref: 
https://lore.kernel.org/qemu-devel/65b8771bfecada08bf02c9cf87c2f0f9cdf943b3.1617281290.git.haibo.xu@linaro.org/

Signed-off-by: Haibo Xu <haibo.xu@linaro.org>
Signed-off-by: Miguel Luis <miguel.luis@oracle.com>
---
 target/arm/kvm64.c   |  5 +++++
 target/arm/kvm_arm.h | 12 ++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 1197253d12..be8144a2b5 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -754,6 +754,11 @@ bool kvm_arm_aarch32_supported(void)
     return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL1_32BIT);
 }
 
+bool kvm_arm_el2_supported(void)
+{
+    return kvm_check_extension(kvm_state, KVM_CAP_ARM_EL2);
+}
+
 bool kvm_arm_sve_supported(void)
 {
     return kvm_check_extension(kvm_state, KVM_CAP_ARM_SVE);
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index 99017b635c..86a0cb4308 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -305,6 +305,13 @@ bool kvm_arm_pmu_supported(void);
  */
 bool kvm_arm_sve_supported(void);
 
+/**
+ * kvm_arm_el2_supported:
+ *
+ * Returns true if KVM can enable EL2 and false otherwise.
+ */
+bool kvm_arm_el2_supported(void);
+
 /**
  * kvm_arm_get_max_vm_ipa_size:
  * @ms: Machine state handle
@@ -395,6 +402,11 @@ static inline bool kvm_arm_steal_time_supported(void)
     return false;
 }
 
+static inline bool kvm_arm_el2_supported(void)
+{
+    return false;
+}
+
 /*
  * These functions should never actually be called without KVM support.
  */
-- 
2.39.2