intel_iommu: provide vtd_ce_get_type()

Helper to fetch VT-d context entry type.
Signed-off-by: NPeter Xu <peterx@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NJason Wang <jasowang@redhat.com>

hw/i386/intel_iommu.c

@@ -595,6 +595,11 @@ static inline uint32_t vtd_ce_get_agaw(VTDContextEntry *ce)
     return 30 + (ce->hi & VTD_CONTEXT_ENTRY_AW) * 9;
 }
 
+static inline uint32_t vtd_ce_get_type(VTDContextEntry *ce)
+{
+    return ce->lo & VTD_CONTEXT_ENTRY_TT;
+}
+
 static inline uint64_t vtd_iova_limit(VTDContextEntry *ce)
 {
     uint32_t ce_agaw = vtd_ce_get_agaw(ce);
@@ -865,7 +870,7 @@ static int vtd_dev_to_context_entry(IntelIOMMUState *s, uint8_t bus_num,
         trace_vtd_ce_invalid(ce->hi, ce->lo);
         return -VTD_FR_CONTEXT_ENTRY_INV;
     } else {
-        switch (ce->lo & VTD_CONTEXT_ENTRY_TT) {
+        switch (vtd_ce_get_type(ce)) {
         case VTD_CONTEXT_TT_MULTI_LEVEL:
             /* fall through */
         case VTD_CONTEXT_TT_DEV_IOTLB: