diff --git a/OvmfPkg/XenBusDxe/GrantTable.c b/OvmfPkg/XenBusDxe/GrantTable.c
index b17fef3605..f68a8542b5 100644
--- a/OvmfPkg/XenBusDxe/GrantTable.c
+++ b/OvmfPkg/XenBusDxe/GrantTable.c
@@ -74,7 +74,7 @@ XenGrantTableGetFreeEntry (
   VOID
   )
 {
-  UINTN Ref;
+  grant_ref_t Ref;
 
   EfiAcquireLock (&mGrantListLock);
   Ref = GrantList[0];
@@ -97,7 +97,7 @@ XenGrantTableGrantAccess (
   )
 {
   grant_ref_t Ref;
-  UINT32 Flags;
+  UINT16 Flags;
 
   ASSERT (GrantTable != NULL);
   Ref = XenGrantTableGetFreeEntry ();
diff --git a/OvmfPkg/XenBusDxe/XenHypercall.c b/OvmfPkg/XenBusDxe/XenHypercall.c
index 0f2ba5d693..15e9e1c799 100644
--- a/OvmfPkg/XenBusDxe/XenHypercall.c
+++ b/OvmfPkg/XenBusDxe/XenHypercall.c
@@ -43,7 +43,7 @@ XenHyperpageInit (
 UINT64
 XenHypercallHvmGetParam (
   IN XENBUS_DEVICE *Dev,
-  IN INTN          Index
+  IN UINT32        Index
   )
 {
   xen_hvm_param_t     Parameter;
diff --git a/OvmfPkg/XenBusDxe/XenHypercall.h b/OvmfPkg/XenBusDxe/XenHypercall.h
index 3627b1886c..9cac17da2b 100644
--- a/OvmfPkg/XenBusDxe/XenHypercall.h
+++ b/OvmfPkg/XenBusDxe/XenHypercall.h
@@ -60,7 +60,7 @@ XenHyperpageInit (
 UINT64
 XenHypercallHvmGetParam (
   XENBUS_DEVICE *Dev,
-  INTN Index
+  UINT32 Index
   );
 
 /**