[Qemu-devel] [PATCH] PPC: e500: set has-idle in guest device tree

[Stuart Yoder]

From: Stuart Yoder <address@hidden>

If the host kernel supports the idle hcall, then advertise
that to the guest kernel via the device tree.

Signed-off-by: Stuart Yoder <address@hidden>
---
 hw/ppce500_mpc8544ds.c |    5 +++++
 target-ppc/kvm.c       |   26 +++++++++++++++++++++++---
 target-ppc/kvm_ppc.h   |    1 +
 3 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/hw/ppce500_mpc8544ds.c b/hw/ppce500_mpc8544ds.c
index b1a0b8c..7d111bb 100644
--- a/hw/ppce500_mpc8544ds.c
+++ b/hw/ppce500_mpc8544ds.c
@@ -124,6 +124,11 @@ static int mpc8544_load_device_tree(CPUPPCState *env,
         kvmppc_get_hypercall(env, hypercall, sizeof(hypercall));
         qemu_devtree_setprop(fdt, "/hypervisor", "hcall-instructions",
                              hypercall, sizeof(hypercall));
+
+        /* add "has-idle" prop if KVM supports ePAPR idle */
+        if (kvmppc_get_hasidle(env)) {
+            qemu_devtree_setprop(fdt, "/hypervisor", "has-idle", NULL, 0);
+        }
     }
 
     /* We need to generate the cpu nodes in reverse order, so Linux can pick
diff --git a/target-ppc/kvm.c b/target-ppc/kvm.c
index c09cc39..f986de3 100644
--- a/target-ppc/kvm.c
+++ b/target-ppc/kvm.c
@@ -705,16 +705,36 @@ uint32_t kvmppc_get_dfp(void)
     return kvmppc_read_int_cpu_dt("ibm,dfp");
 }
 
+static int kvmppc_get_pvinfo(CPUPPCState *env, struct kvm_ppc_pvinfo *pvinfo)
+{
+    if (kvm_check_extension(env->kvm_state, KVM_CAP_PPC_GET_PVINFO) &&
+        !kvm_vm_ioctl(env->kvm_state, KVM_PPC_GET_PVINFO, pvinfo)) {
+        return 0;
+    }
+
+    return 1;
+}
+
+int kvmppc_get_hasidle(CPUPPCState *env)
+{
+    struct kvm_ppc_pvinfo pvinfo;
+
+    if (!kvmppc_get_pvinfo(env, &pvinfo) &&
+        (pvinfo.flags & KVM_PPC_PVINFO_FLAGS_EV_IDLE)) {
+        return 1;
+    }
+
+    return 0;
+}
+
 int kvmppc_get_hypercall(CPUPPCState *env, uint8_t *buf, int buf_len)
 {
     uint32_t *hc = (uint32_t*)buf;
 
     struct kvm_ppc_pvinfo pvinfo;
 
-    if (kvm_check_extension(env->kvm_state, KVM_CAP_PPC_GET_PVINFO) &&
-        !kvm_vm_ioctl(env->kvm_state, KVM_PPC_GET_PVINFO, &pvinfo)) {
+    if (!kvmppc_get_pvinfo(env, &pvinfo)) {
         memcpy(buf, pvinfo.hcall, buf_len);
-
         return 0;
     }
 
diff --git a/target-ppc/kvm_ppc.h b/target-ppc/kvm_ppc.h
index 34ecad3..c2c75b6 100644
--- a/target-ppc/kvm_ppc.h
+++ b/target-ppc/kvm_ppc.h
@@ -19,6 +19,7 @@ uint32_t kvmppc_get_tbfreq(void);
 uint64_t kvmppc_get_clockfreq(void);
 uint32_t kvmppc_get_vmx(void);
 uint32_t kvmppc_get_dfp(void);
+int kvmppc_get_hasidle(CPUPPCState *env);
 int kvmppc_get_hypercall(CPUPPCState *env, uint8_t *buf, int buf_len);
 int kvmppc_set_interrupt(CPUPPCState *env, int irq, int level);
 void kvmppc_set_papr(CPUPPCState *env);
-- 
1.7.3.4