diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -3110,6 +3110,37 @@
         break;
     }
 
+    case HVMOP_enable_pv: {
+        struct xen_hvm_pv_type a;
+        struct domain *d;
+
+        if ( copy_from_guest(&a, arg, 1) )
+            return -EFAULT;
+
+        rc = rcu_lock_target_domain_by_id(DOMID_SELF, &d);
+        if ( rc != 0 )
+            return rc;
+
+        rc = -EINVAL;
+        if ( !is_hvm_domain(d) )
+            goto param_fail5;
+
+        rc = xsm_hvm_param(d, op);
+        if ( rc )
+            goto param_fail5;
+
+	/* This would be called by BSP, other vcpus are adjusted during the
+	 * start-up */
+	if (a.flags & HVM_PV_CLOCK) {
+		d->hvm_pv_enabled |= XEN_HVM_PV_CLOCK_ENABLED;
+		update_domain_wallclock_time(d);
+		hvm_funcs.set_tsc_offset(current, 0);
+	}
+param_fail5:
+        rcu_unlock_domain(d);
+        break;
+    }
+
     default:
     {
         gdprintk(XENLOG_WARNING, "Bad HVM op %ld.\n", op);
diff --git a/xen/arch/x86/hvm/vlapic.c b/xen/arch/x86/hvm/vlapic.c
--- a/xen/arch/x86/hvm/vlapic.c
+++ b/xen/arch/x86/hvm/vlapic.c
@@ -289,6 +289,10 @@
         return X86EMUL_RETRY;
 
     hvm_vcpu_reset_state(v, trampoline_vector << 8, 0);
+
+    /* Adjust TSC for PV clock */
+    if (is_hvm_pv_clock_enabled_domain(v->domain))
+        hvm_funcs.set_tsc_offset(v, 0);
 
     vcpu_unpause(v);
 
diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -686,6 +686,7 @@
     struct domain *d = current->domain;
     /* Optionally shift out of the way of Viridian architectural leaves. */
     uint32_t base = is_viridian_domain(d) ? 0x40000100 : 0x40000000;
+    unsigned int tmp_eax, tmp_ebx, tmp_ecx, tmp_edx;
 
     idx -= base;
     if ( idx > 3 ) 
@@ -716,6 +717,14 @@
         *edx = 0;          /* Features 2 */
         if ( !is_hvm_vcpu(current) )
             *ecx |= XEN_CPUID_FEAT1_MMU_PT_UPDATE_PRESERVE_AD;
+
+        /* Check if additional feature specified, e.g. Hybrid */
+        if ( !is_viridian_domain(d) ) {
+            domain_cpuid(d, 0x40000002, 0,
+                         &tmp_eax, &tmp_ebx, &tmp_ecx, &tmp_edx);
+            if (tmp_edx != 0)
+                *edx = tmp_edx & XEN_CPUID_FEAT2_MASK;
+        }
         break;
 
     case 3:
diff --git a/xen/include/public/arch-x86/cpuid.h b/xen/include/public/arch-x86/cpuid.h
--- a/xen/include/public/arch-x86/cpuid.h
+++ b/xen/include/public/arch-x86/cpuid.h
@@ -65,4 +65,11 @@
 #define _XEN_CPUID_FEAT1_MMU_PT_UPDATE_PRESERVE_AD 0
 #define XEN_CPUID_FEAT1_MMU_PT_UPDATE_PRESERVE_AD  (1u<<0)
 
+/* Mask unsupported CPUID specified by user */
+#define XEN_CPUID_FEAT2_MASK 0x3ul
+#define _XEN_CPUID_FEAT2_HVM_PV 0
+#define XEN_CPUID_FEAT2_HVM_PV (1u<<0)
+#define _XEN_CPUID_FEAT2_HVM_PV_CLOCK 1
+#define XEN_CPUID_FEAT2_HVM_PV_CLOCK (1u<<1)
+
 #endif /* __XEN_PUBLIC_ARCH_X86_CPUID_H__ */
diff --git a/xen/include/public/hvm/hvm_op.h b/xen/include/public/hvm/hvm_op.h
--- a/xen/include/public/hvm/hvm_op.h
+++ b/xen/include/public/hvm/hvm_op.h
@@ -127,6 +127,13 @@
 typedef struct xen_hvm_set_mem_type xen_hvm_set_mem_type_t;
 DEFINE_XEN_GUEST_HANDLE(xen_hvm_set_mem_type_t);
 
+/* Enable PV extended HVM features. Should called by BSP */
+#define HVMOP_enable_pv 9
+struct xen_hvm_pv_type {
+    /* The features want to enable */
+    uint32_t flags;
+#define HVM_PV_CLOCK  (1ull<<0)
+};
 
 #endif /* defined(__XEN__) || defined(__XEN_TOOLS__) */
 
diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -311,6 +311,9 @@
 
     /* Memory paging support */
     struct mem_event_domain mem_event;
+
+#define XEN_HVM_PV_CLOCK_ENABLED   (1u << 0)
+    uint64_t hvm_pv_enabled;
 };
 
 struct domain_setup_info
@@ -597,6 +600,9 @@
 #define is_hvm_vcpu(v)   (is_hvm_domain(v->domain))
 #define need_iommu(d)    ((d)->need_iommu)
 
+#define is_hvm_pv_clock_enabled_domain(d) \
+                         ((d)->hvm_pv_enabled & XEN_HVM_PV_CLOCK_ENABLED)
+
 void set_vcpu_migration_delay(unsigned int delay);
 unsigned int get_vcpu_migration_delay(void);