diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index f646c1ee7b..e0cb82d2a3 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -60,6 +60,7 @@
 #include <asm/hvm/nestedhvm.h>
 #include <asm/hvm/event.h>
 #include <asm/hvm/vmx/vmx.h>
+#include <asm/hvm/svm/svm.h> /* for cpu_has_tsc_ratio */
 #include <asm/altp2m.h>
 #include <asm/mtrr.h>
 #include <asm/apic.h>
@@ -310,13 +311,11 @@ void hvm_set_guest_tsc_fixed(struct vcpu *v, u64 guest_tsc, u64 at_tsc)
         tsc = hvm_get_guest_time_fixed(v, at_tsc);
         tsc = gtime_to_gtsc(v->domain, tsc);
     }
-    else if ( at_tsc )
-    {
-        tsc = at_tsc;
-    }
     else
     {
-        tsc = rdtsc();
+        tsc = at_tsc ?: rdtsc();
+        if ( cpu_has_tsc_ratio )
+            tsc = hvm_funcs.scale_tsc(v, tsc);
     }
 
     delta_tsc = guest_tsc - tsc;
@@ -344,13 +343,11 @@ u64 hvm_get_guest_tsc_fixed(struct vcpu *v, uint64_t at_tsc)
         tsc = hvm_get_guest_time_fixed(v, at_tsc);
         tsc = gtime_to_gtsc(v->domain, tsc);
     }
-    else if ( at_tsc )
-    {
-        tsc = at_tsc;
-    }
     else
     {
-        tsc = rdtsc();
+        tsc = at_tsc ?: rdtsc();
+        if ( cpu_has_tsc_ratio )
+            tsc = hvm_funcs.scale_tsc(v, tsc);
     }
 
     return tsc + v->arch.hvm_vcpu.cache_tsc_offset;
diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c
index a66d854480..a46bc98576 100644
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -804,6 +804,13 @@ static uint64_t scale_tsc(uint64_t host_tsc, uint64_t ratio)
     return scaled_host_tsc;
 }
 
+static uint64_t svm_scale_tsc(const struct vcpu *v, uint64_t tsc)
+{
+    ASSERT(cpu_has_tsc_ratio && !v->domain->arch.vtsc);
+
+    return scale_tsc(tsc, vcpu_tsc_ratio(v));
+}
+
 static uint64_t svm_get_tsc_offset(uint64_t host_tsc, uint64_t guest_tsc,
     uint64_t ratio)
 {
@@ -2272,6 +2279,8 @@ static struct hvm_function_table __initdata svm_function_table = {
     .nhvm_vmcx_hap_enabled = nsvm_vmcb_hap_enabled,
     .nhvm_intr_blocked = nsvm_intr_blocked,
     .nhvm_hap_walk_L1_p2m = nsvm_hap_walk_L1_p2m,
+
+    .scale_tsc            = svm_scale_tsc,
 };
 
 void svm_vmexit_handler(struct cpu_user_regs *regs)
diff --git a/xen/include/asm-x86/hvm/hvm.h b/xen/include/asm-x86/hvm/hvm.h
index b9d893d1e2..a87224b138 100644
--- a/xen/include/asm-x86/hvm/hvm.h
+++ b/xen/include/asm-x86/hvm/hvm.h
@@ -212,6 +212,8 @@ struct hvm_function_table {
     void (*altp2m_vcpu_update_vmfunc_ve)(struct vcpu *v);
     bool_t (*altp2m_vcpu_emulate_ve)(struct vcpu *v);
     int (*altp2m_vcpu_emulate_vmfunc)(struct cpu_user_regs *regs);
+
+    uint64_t (*scale_tsc)(const struct vcpu *v, uint64_t tsc);
 };
 
 extern struct hvm_function_table hvm_funcs;