ich9: Document why cannot_instantiate_with_device_add_yet

An ICH9 southbridge contains several PCI devices, some of them with
multiple functions.  We model each function as a separate qdev.  Two
of them need some special wiring set up in pc_q35_init() to work: the
LPC controller at 00:1f.0, and the SMBus controller at 00:1f.3.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>

1 files changed, 5 insertions, 2 deletions

diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index c1ca4d4f71..51ce12dad6 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -644,14 +644,17 @@ static void ich9_lpc_class_init(ObjectClass *klass, void *data)
     dc->reset = ich9_lpc_reset;
     k->init = ich9_lpc_initfn;
     dc->vmsd = &vmstate_ich9_lpc;
-    dc->cannot_instantiate_with_device_add_yet = true; /* FIXME explain why */
     k->config_write = ich9_lpc_config_write;
     dc->desc = "ICH9 LPC bridge";
     k->vendor_id = PCI_VENDOR_ID_INTEL;
     k->device_id = PCI_DEVICE_ID_INTEL_ICH9_8;
     k->revision = ICH9_A2_LPC_REVISION;
     k->class_id = PCI_CLASS_BRIDGE_ISA;
-
+    /*
+     * Reason: part of ICH9 southbridge, needs to be wired up by
+     * pc_q35_init()
+     */
+    dc->cannot_instantiate_with_device_add_yet = true;
 }
 
 static const TypeInfo ich9_lpc_info = {