[PATCH v2 10/12] target/arm/cpu: spe: Enable spe to work with host cpu

[Haibo Xu]

Turn on the spe cpu property by default if host cpu
support it, i.e. we can now do '-cpu max|host' to add
the vSPE, and '-cpu max|host,spe=off' to remove it.

Signed-off-by: Haibo Xu <haibo...@linaro.org>
---
 target/arm/cpu.c   |  3 +++
 target/arm/cpu.h   |  2 ++
 target/arm/cpu64.c |  7 ++++++-
 target/arm/kvm64.c | 12 ++++++++++++
 4 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 786cc6134c..58f12d6eb5 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -2271,6 +2271,9 @@ static void arm_host_initfn(Object *obj)
     kvm_arm_set_cpu_features_from_host(cpu);
     if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
         aarch64_add_sve_properties(obj);
+
+        cpu->has_spe = ON_OFF_AUTO_AUTO;
+        aarch64_add_spe_properties(obj);
     }
     arm_cpu_post_init(obj);
 }
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 395a1e5df8..5a3ea876c8 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1040,6 +1040,7 @@ void aarch64_sve_narrow_vq(CPUARMState *env, unsigned vq);
 void aarch64_sve_change_el(CPUARMState *env, int old_el,
                            int new_el, bool el0_a64);
 void aarch64_add_sve_properties(Object *obj);
+void aarch64_add_spe_properties(Object *obj);
 
 /*
  * SVE registers are encoded in KVM's memory in an endianness-invariant format.
@@ -1071,6 +1072,7 @@ static inline void aarch64_sve_change_el(CPUARMState 
*env, int o,
                                          int n, bool a)
 { }
 static inline void aarch64_add_sve_properties(Object *obj) { }
+static inline void aarch64_add_spe_properties(Object *obj) { }
 #endif
 
 #if !defined(CONFIG_TCG)
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 4997c4a3c0..d38c55e2ca 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -621,6 +621,11 @@ static void arm_spe_set(Object *obj, bool value, Error 
**errp)
     ARM_CPU(obj)->has_spe = value ? ON_OFF_AUTO_ON : ON_OFF_AUTO_OFF;
 }
 
+void aarch64_add_spe_properties(Object *obj)
+{
+    object_property_add_bool(obj, "spe", arm_spe_get, arm_spe_set);
+}
+
 /* -cpu max: if KVM is enabled, like -cpu host (best possible with this host);
  * otherwise, a CPU with as many features enabled as our emulation supports.
  * The version of '-cpu max' for qemu-system-arm is defined in cpu.c;
@@ -772,7 +777,7 @@ static void aarch64_max_initfn(Object *obj)
                         cpu_max_set_sve_max_vq, NULL, NULL);
 
     cpu->has_spe = ON_OFF_AUTO_AUTO;
-    object_property_add_bool(obj, "spe", arm_spe_get, arm_spe_set);
+    aarch64_add_spe_properties(obj);
 }
 
 static const ARMCPUInfo aarch64_cpus[] = {
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 5a2032fc9e..3f0a09c05b 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -515,6 +515,7 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
      */
     int fdarray[3];
     bool sve_supported;
+    bool spe_supported;
     uint64_t features = 0;
     uint64_t t;
     int err;
@@ -655,6 +656,8 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
     }
 
     sve_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION, KVM_CAP_ARM_SVE) > 
0;
+    spe_supported = ioctl(fdarray[0], KVM_CHECK_EXTENSION,
+                                      KVM_CAP_ARM_SPE_V1) > 0;
 
     kvm_arm_destroy_scratch_host_vcpu(fdarray);
 
@@ -668,6 +671,11 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures 
*ahcf)
         t = FIELD_DP64(t, ID_AA64PFR0, SVE, 1);
         ahcf->isar.id_aa64pfr0 = t;
     }
+    if (!spe_supported) {
+        t = ahcf->isar.id_aa64dfr0;
+        t = FIELD_DP64(t, ID_AA64DFR0, PMSVER, 0);
+        ahcf->isar.id_aa64dfr0 = t;
+    }
 
     /*
      * We can assume any KVM supporting CPU is at least a v8
@@ -830,6 +838,10 @@ int kvm_arch_init_vcpu(CPUState *cs)
         assert(kvm_arm_sve_supported());
         cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_SVE;
     }
+    if (cpu_isar_feature(aa64_spe, cpu)) {
+        assert(kvm_arm_spe_supported());
+        cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_SPE_V1;
+    }
 
     /* Do KVM_ARM_VCPU_INIT ioctl */
     ret = kvm_arm_vcpu_init(cs);
-- 
2.17.1