[RFC v2 11/15] hw/core: Support topology tree in none machine for compatibility

[Zhao Liu <zhao1.liu@intel.com>]

None machine accepts any CPU types, even some CPUs may have the
bus_type.

To address this, set topo_tree_supported as true for none machine, then
none machine will have a CPU slot with CPU bus to collect any topology
device with bus_type specified.

And since arch_id_topo_level is not set, the topology devices will be
directly inserted under the CPU slot without being organized into a tree
structure.

For the CPUs without bus_type, topo_tree_supported will not affect them.

Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
---
 hw/core/null-machine.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/hw/core/null-machine.c b/hw/core/null-machine.c
index f586a4bef543..101649f3e8c1 100644
--- a/hw/core/null-machine.c
+++ b/hw/core/null-machine.c
@@ -54,6 +54,11 @@ static void machine_none_machine_init(MachineClass *mc)
     mc->no_floppy = 1;
     mc->no_cdrom = 1;
     mc->no_sdcard = 1;
+    /*
+     * For compatibility with arches and CPUs that already
+     * support topology tree.
+     */
+    mc->smp_props.topo_tree_supported = true;
 }
 
 DEFINE_MACHINE("none", machine_none_machine_init)
-- 
2.34.1