hw/mips: Implement the kvm_type() hook in MachineClass

MIPS has two types of KVM: TE & VZ, and TE is the default type. Now we
can't create a VZ guest in QEMU because it lacks the kvm_type() hook in
MachineClass. This patch add the the kvm_type() hook to support both of
the two types.

[AM: Added "if defined" guards.]

Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Signed-off-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Co-developed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-Id: <1592995531-32600-2-git-send-email-chenhc@lemote.com>
diff --git a/target/mips/kvm.c b/target/mips/kvm.c
index 96cfa10..72637a1 100644
--- a/target/mips/kvm.c
+++ b/target/mips/kvm.c
@@ -21,10 +21,12 @@
 #include "qemu/main-loop.h"
 #include "qemu/timer.h"
 #include "sysemu/kvm.h"
+#include "sysemu/kvm_int.h"
 #include "sysemu/runstate.h"
 #include "sysemu/cpus.h"
 #include "kvm_mips.h"
 #include "exec/memattrs.h"
+#include "hw/boards.h"
 
 #define DEBUG_KVM 0
 
@@ -1270,3 +1272,27 @@
 {
     abort();
 }
+
+int mips_kvm_type(MachineState *machine, const char *vm_type)
+{
+#if defined(KVM_CAP_MIPS_VZ) || defined(KVM_CAP_MIPS_TE)
+    int r;
+    KVMState *s = KVM_STATE(machine->accelerator);
+#endif
+
+#if defined(KVM_CAP_MIPS_VZ)
+    r = kvm_check_extension(s, KVM_CAP_MIPS_VZ);
+    if (r > 0) {
+        return KVM_VM_MIPS_VZ;
+    }
+#endif
+
+#if defined(KVM_CAP_MIPS_TE)
+    r = kvm_check_extension(s, KVM_CAP_MIPS_TE);
+    if (r > 0) {
+        return KVM_VM_MIPS_TE;
+    }
+#endif
+
+    return -1;
+}
diff --git a/target/mips/kvm_mips.h b/target/mips/kvm_mips.h
index 1e40147..171d53d 100644
--- a/target/mips/kvm_mips.h
+++ b/target/mips/kvm_mips.h
@@ -12,6 +12,8 @@
 #ifndef KVM_MIPS_H
 #define KVM_MIPS_H
 
+#include "cpu.h"
+
 /**
  * kvm_mips_reset_vcpu:
  * @cpu: MIPSCPU
@@ -23,4 +25,13 @@
 int kvm_mips_set_interrupt(MIPSCPU *cpu, int irq, int level);
 int kvm_mips_set_ipi_interrupt(MIPSCPU *cpu, int irq, int level);
 
+#ifdef CONFIG_KVM
+int mips_kvm_type(MachineState *machine, const char *vm_type);
+#else
+static inline int mips_kvm_type(MachineState *machine, const char *vm_type)
+{
+    return 0;
+}
+#endif
+
 #endif /* KVM_MIPS_H */