pc: Add x86_topo_ids_from_apicid()

It's reverse of apicid_from_topo_ids() and will be used in follow up
patches to fill in data structures for query-hotpluggable-cpus and
for user friendly error reporting.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

diff --git a/include/hw/i386/topology.h b/include/hw/i386/topology.h
index fc95572394a312b9d4f63554dd9ec0a6556d4c17..1ebaee0f762ef927d612a42546cd33e85f7b215c 100644 (file)
--- a/include/hw/i386/topology.h
+++ b/include/hw/i386/topology.h
@@ -117,6 +117,21 @@ static inline void x86_topo_ids_from_idx(unsigned nr_cores,
     topo->pkg_id = core_index / nr_cores;
 }
 
+/* Calculate thread/core/package IDs for a specific topology,
+ * based on APIC ID
+ */
+static inline void x86_topo_ids_from_apicid(apic_id_t apicid,
+                                            unsigned nr_cores,
+                                            unsigned nr_threads,
+                                            X86CPUTopoInfo *topo)
+{
+    topo->smt_id = apicid &
+                   ~(0xFFFFFFFFUL << apicid_smt_width(nr_cores, nr_threads));
+    topo->core_id = (apicid >> apicid_core_offset(nr_cores, nr_threads)) &
+                   ~(0xFFFFFFFFUL << apicid_core_width(nr_cores, nr_threads));
+    topo->pkg_id = apicid >> apicid_pkg_offset(nr_cores, nr_threads);
+}
+
 /* Make APIC ID for the CPU 'cpu_index'
  *
  * 'cpu_index' is a sequential, contiguous ID for the CPU.