@@ -6555,6 +6555,41 @@ KVM_S390_KEYOP_SSKE
.. _kvm_run:
+4.145 KVM_PPC_GET_COMPAT_CAPS
+-----------------------------
+:Capability: KVM_CAP_PPC_COMPAT_CAPS
+:Architectures: powerpc
+:Type: vm ioctl
+:Parameters: struct kvm_ppc_compat_caps (out)
+:Returns:
+ 0 on successful completion,
+ -EFAULT if ``struct kvm_ppc_compat_caps`` cannot be written
+
+IBM POWER system server-based processors provide a compatibility mode feature
+where an Nth generation processor can operate in modes consistent with earlier
+generations such as (N-1) and (N-2).
+
+This ioctl provides userspace with information about the CPU compatibility modes
+supported by the current host processor for booting the nested KVM guests on
+PowerNV (KVM nested APIv1) and PowerVM (KVM nested APIv2) platforms.
+
+::
+
+ struct kvm_ppc_compat_caps {
+ __u64 flags; /* Reserved for future use */
+ __u64 compat_capabilities; /* Capabilities supported by the host */
+ };
+
+The ``compat_capabilities`` bit field describes the processor compatibility
+modes supported by the host. For example, the following bits indicate support
+for specific processor modes.
+
+::
+
+H_GUEST_CAP_POWER9 (bit 1): KVM guests can run in Power9 processor mode
+H_GUEST_CAP_POWER10 (bit 2): KVM guests can run in Power10 processor mode
+H_GUEST_CAP_POWER11 (bit 3): KVM guests can run in Power11 processor mode
+
5. The kvm_run structure
========================
Add documentation for the KVM_PPC_GET_COMPAT_CAPS ioctl to the KVM API documentation. The ioctl exposes host processor compatibility modes supported for nested KVM guests on PowerPC systems. Signed-off-by: Amit Machhiwal <amachhiw@linux.ibm.com> --- Documentation/virt/kvm/api.rst | 35 ++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+)